National Library of Energy BETA

Sample records for lithography mask defects

  1. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    EUV lithography relies on specialized lenses made of curved mirrors with reflective coatings called multilayers to print patterns with high resolution. One special flat mirror...

  2. Printability and inspectability of programmed pit defects on teh masks in EUV lithography

    SciTech Connect (OSTI)

    Kang, I.-Y.; Seo, H.-S.; Ahn, B.-S.; Lee, D.-G.; Kim, D.; Huh, S.; Koh, C.-W.; Cha, B.; Kim, S.-S.; Cho, H.-K.; Mochi, I.; Goldberg, K. A.

    2010-03-12

    Printability and inspectability of phase defects in ELlVL mask originated from substrate pit were investigated. For this purpose, PDMs with programmed pits on substrate were fabricated using different ML sources from several suppliers. Simulations with 32-nm HP L/S show that substrate pits with below {approx}20 nm in depth would not be printed on the wafer if they could be smoothed by ML process down to {approx}1 nm in depth on ML surface. Through the investigation of inspectability for programmed pits, minimum pit sizes detected by KLA6xx, AIT, and M7360 depend on ML smoothing performance. Furthermore, printability results for pit defects also correlate with smoothed pit sizes. AIT results for pattemed mask with 32-nm HP L/S represents that minimum printable size of pits could be {approx}28.3 nm of SEVD. In addition, printability of pits became more printable as defocus moves to (-) directions. Consequently, printability of phase defects strongly depends on their locations with respect to those of absorber patterns. This indicates that defect compensation by pattern shift could be a key technique to realize zero printable phase defects in EUVL masks.

  3. Inspection of lithographic mask blanks for defects

    DOE Patents [OSTI]

    Sommargren, Gary E. (Santa Cruz, CA)

    2001-01-01

    A visible light method for detecting sub-100 nm size defects on mask blanks used for lithography. By using optical heterodyne techniques, detection of the scattered light can be significantly enhanced as compared to standard intensity detection methods. The invention is useful in the inspection of super-polished surfaces for isolated surface defects or particulate contamination and in the inspection of lithographic mask or reticle blanks for surface defects or bulk defects or for surface particulate contamination.

  4. Method and apparatus for inspecting reflection masks for defects

    DOE Patents [OSTI]

    Bokor, Jeffrey (Oakland, CA); Lin, Yun (Berkeley, CA)

    2003-04-29

    An at-wavelength system for extreme ultraviolet lithography mask blank defect detection is provided. When a focused beam of wavelength 13 nm is incident on a defective region of a mask blank, three possible phenomena can occur. The defect will induce an intensity reduction in the specularly reflected beam, scatter incoming photons into an off-specular direction, and change the amplitude and phase of the electric field at the surface which can be monitored through the change in the photoemission current. The magnitude of these changes will depend on the incident beam size, and the nature, extent and size of the defect. Inspection of the mask blank is performed by scanning the mask blank with 13 nm light focused to a spot a few .mu.m in diameter, while measuring the reflected beam intensity (bright field detection), the scattered beam intensity (dark-field detection) and/or the change in the photoemission current.

  5. Vitreous carbon mask substrate for X-ray lithography

    DOE Patents [OSTI]

    Aigeldinger, Georg (Livermore, CA); Skala, Dawn M. (Fremont, CA); Griffiths, Stewart K. (Livermore, CA); Talin, Albert Alec (Livermore, CA); Losey, Matthew W. (Livermore, CA); Yang, Chu-Yeu Peter (Dublin, CA)

    2009-10-27

    The present invention is directed to the use of vitreous carbon as a substrate material for providing masks for X-ray lithography. The new substrate also enables a small thickness of the mask absorber used to pattern the resist, and this enables improved mask accuracy. An alternative embodiment comprised the use of vitreous carbon as a LIGA substrate wherein the VC wafer blank is etched in a reactive ion plasma after which an X-ray resist is bonded. This surface treatment provides a surface enabling good adhesion of the X-ray photoresist and subsequent nucleation and adhesion of the electrodeposited metal for LIGA mold-making while the VC substrate practically eliminates secondary radiation effects that lead to delamination of the X-ray resist form the substrate, the loss of isolated resist features, and the formation of a resist layer adjacent to the substrate that is insoluble in the developer.

  6. An EUV Fresnel zoneplate mask-imaging microscope for lithography generations reaching 8 nm

    E-Print Network [OSTI]

    An EUV Fresnel zoneplate mask-imaging microscope for lithography generations reaching 8 nm Kenneth lithography design rules. The proposed microscope features an array of user-selectable Fresnel zoneplate-EUV, Fresnel zoneplate microscope, the AIT has been in the vanguard of high-resolution EUV mask imaging

  7. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    with SEMATECH, an international semiconductor industry consortium, to create a unique Fresnel zone-plate microscope on Advanced Light Source Beamline 11.3.2 called the SEMATECH...

  8. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATIONIntroducing the Richard P. FeynmanInventors in

  9. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATIONIntroducing the Richard P. FeynmanInventors inInvestigating

  10. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATIONIntroducing the Richard P. FeynmanInventors

  11. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATIONIntroducing the Richard P. FeynmanInventorsInvestigating

  12. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATIONIntroducing the Richard P.

  13. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation CurrentHenryInhibitingInteractivePGAS and HybridBetoniCenter for

  14. Investigating Extreme Ultraviolet Lithography Mask Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation CurrentHenryInhibitingInteractivePGAS and HybridBetoniCenter forInvestigating

  15. Energy flow in light-coupling masks for lensless optical lithography

    E-Print Network [OSTI]

    Floreano, Dario

    Energy flow in light-coupling masks for lensless optical lithography Olivier J. F. Martin@zurich.ibm.com Abstract: We illustrate the propagation of light in a new type of coupling mask for lensless optical. Biebuck, B. Michel, O.J.F. Martin and N.B. Piller, "Light-coupling masks: an alternative, lensless

  16. Commissioning a new EUV Fresnel zoneplate mask-imaging microscope for lithography generations reaching 8 nm

    E-Print Network [OSTI]

    Goldberg, Kenneth A.

    2014-01-01

    Commissioning a new EUV Fresnel zoneplate mask-imagingimaging system relies on Fresnel zoneplate lenses, which

  17. Method for characterizing mask defects using image reconstruction from X-ray diffraction patterns

    DOE Patents [OSTI]

    Hau-Riege, Stefan Peter (Fremont, CA)

    2007-05-01

    The invention applies techniques for image reconstruction from X-ray diffraction patterns on the three-dimensional imaging of defects in EUVL multilayer films. The reconstructed image gives information about the out-of-plane position and the diffraction strength of the defect. The positional information can be used to select the correct defect repair technique. This invention enables the fabrication of defect-free (since repaired) X-ray Mo--Si multilayer mirrors. Repairing Mo--Si multilayer-film defects on mask blanks is a key for the commercial success of EUVL. It is known that particles are added to the Mo--Si multilayer film during the fabrication process. There is a large effort to reduce this contamination, but results are not sufficient, and defects continue to be a major mask yield limiter. All suggested repair strategies need to know the out-of-plane position of the defects in the multilayer.

  18. Context-based automated defect classification system using multiple morphological masks

    DOE Patents [OSTI]

    Gleason, Shaun S. (Knoxville, TN); Hunt, Martin A. (Knoxville, TN); Sari-Sarraf, Hamed (Lubbock, TX)

    2002-01-01

    Automatic detection of defects during the fabrication of semiconductor wafers is largely automated, but the classification of those defects is still performed manually by technicians. This invention includes novel digital image analysis techniques that generate unique feature vector descriptions of semiconductor defects as well as classifiers that use these descriptions to automatically categorize the defects into one of a set of pre-defined classes. Feature extraction techniques based on multiple-focus images, multiple-defect mask images, and segmented semiconductor wafer images are used to create unique feature-based descriptions of the semiconductor defects. These feature-based defect descriptions are subsequently classified by a defect classifier into categories that depend on defect characteristics and defect contextual information, that is, the semiconductor process layer(s) with which the defect comes in contact. At the heart of the system is a knowledge database that stores and distributes historical semiconductor wafer and defect data to guide the feature extraction and classification processes. In summary, this invention takes as its input a set of images containing semiconductor defect information, and generates as its output a classification for the defect that describes not only the defect itself, but also the location of that defect with respect to the semiconductor process layers.

  19. Method for the manufacture of phase shifting masks for EUV lithography

    DOE Patents [OSTI]

    Stearns, Daniel G.; Sweeney, Donald W.; Mirkarimi, Paul B.; Barty, Anton

    2006-04-04

    A method for fabricating an EUV phase shift mask is provided that includes a substrate upon which is deposited a thin film multilayer coating that has a complex-valued reflectance. An absorber layer or a buffer layer is attached onto the thin film multilayer, and the thickness of the thin film multilayer coating is altered to introduce a direct modulation in the complex-valued reflectance to produce phase shifting features.

  20. Maskless, reticle-free, lithography

    DOE Patents [OSTI]

    Ceglio, Natale M. (Livermore, CA); Markle, David A. (Saratoga, CA)

    1997-11-25

    A lithography system in which the mask or reticle, which usually carries the pattern to be printed onto a substrate, is replaced by a programmable array of binary (i.e. on/off) light valves or switches which can be programmed to replicate a portion of the pattern each time an illuminating light source is flashed. The pattern of light produced by the programmable array is imaged onto a lithographic substrate which is mounted on a scanning stage as is common in optical lithography. The stage motion and the pattern of light displayed by the programmable array are precisely synchronized with the flashing illumination system so that each flash accurately positions the image of the pattern on the substrate. This is achieved by advancing the pattern held in the programmable array by an amount which corresponds to the travel of the substrate stage each time the light source flashes. In this manner the image is built up of multiple flashes and an isolated defect in the array will only have a small effect on the printed pattern. The method includes projection lithographies using radiation other than optical or ultraviolet light. The programmable array of binary switches would be used to control extreme ultraviolet (EUV), x-ray, or electron, illumination systems, obviating the need for stable, defect free masks for projection EUV, x-ray, or electron, lithographies.

  1. Maskless, reticle-free, lithography

    DOE Patents [OSTI]

    Ceglio, N.M.; Markle, D.A.

    1997-11-25

    A lithography system in which the mask or reticle, which usually carries the pattern to be printed onto a substrate, is replaced by a programmable array of binary (i.e. on/off) light valves or switches which can be programmed to replicate a portion of the pattern each time an illuminating light source is flashed. The pattern of light produced by the programmable array is imaged onto a lithographic substrate which is mounted on a scanning stage as is common in optical lithography. The stage motion and the pattern of light displayed by the programmable array are precisely synchronized with the flashing illumination system so that each flash accurately positions the image of the pattern on the substrate. This is achieved by advancing the pattern held in the programmable array by an amount which corresponds to the travel of the substrate stage each time the light source flashes. In this manner the image is built up of multiple flashes and an isolated defect in the array will only have a small effect on the printed pattern. The method includes projection lithographies using radiation other than optical or ultraviolet light. The programmable array of binary switches would be used to control extreme ultraviolet (EUV), x-ray, or electron, illumination systems, obviating the need for stable, defect free masks for projection EUV, x-ray, or electron, lithographies. 7 figs.

  2. VUV lithography

    DOE Patents [OSTI]

    George, Edward V. (Livermore, CA); Oster, Yale (Danville, CA); Mundinger, David C. (Stockton, CA)

    1990-01-01

    Deep UV projection lithography can be performed using an e-beam pumped solid excimer UV source, a mask, and a UV reduction camera. The UV source produces deep UV radiation in the range 1700-1300A using xenon, krypton or argon; shorter wavelengths of 850-650A can be obtained using neon or helium. A thin solid layer of the gas is formed on a cryogenically cooled plate and bombarded with an e-beam to cause fluorescence. The UV reduction camera utilizes multilayer mirrors having high reflectivity at the UV wavelength and images the mask onto a resist coated substrate at a preselected demagnification. The mask can be formed integrally with the source as an emitting mask.

  3. VUV lithography

    DOE Patents [OSTI]

    George, E.V.; Oster, Y.; Mundinger, D.C.

    1990-12-25

    Deep UV projection lithography can be performed using an e-beam pumped solid excimer UV source, a mask, and a UV reduction camera. The UV source produces deep UV radiation in the range 1,700--1,300A using xenon, krypton or argon; shorter wavelengths of 850--650A can be obtained using neon or helium. A thin solid layer of the gas is formed on a cryogenically cooled plate and bombarded with an e-beam to cause fluorescence. The UV reduction camera utilizes multilayer mirrors having high reflectivity at the UV wavelength and images the mask onto a resist coated substrate at a preselected demagnification. The mask can be formed integrally with the source as an emitting mask. 6 figs.

  4. Neon Ion Beam Lithography (NIBL)

    E-Print Network [OSTI]

    Winston, Donald

    Existing techniques for electron- and ion-beam lithography, routinely employed for nanoscale device fabrication and mask/mold prototyping, do not simultaneously achieve efficient (low fluence) exposure and high resolution. ...

  5. Diffractive optics for maskless lithography and imaging

    E-Print Network [OSTI]

    Menon, Rajesh, 1976-

    2003-01-01

    Semiconductor industry has primarily been driven by the capability of lithography to pattern smaller and smaller features. However due to increasing mask costs and complexity, and increasing tool costs, the state-of-the-art ...

  6. Method for fabricating an ultra-low expansion mask blank having a crystalline silicon layer

    DOE Patents [OSTI]

    Cardinale, Gregory F. (Oakland, CA)

    2002-01-01

    A method for fabricating masks for extreme ultraviolet lithography (EUVL) using Ultra-Low Expansion (ULE) substrates and crystalline silicon. ULE substrates are required for the necessary thermal management in EUVL mask blanks, and defect detection and classification have been obtained using crystalline silicon substrate materials. Thus, this method provides the advantages for both the ULE substrate and the crystalline silicon in an Extreme Ultra-Violet (EUV) mask blank. The method is carried out by bonding a crystalline silicon wafer or member to a ULE wafer or substrate and thinning the silicon to produce a 5-10 .mu.m thick crystalline silicon layer on the surface of the ULE substrate. The thinning of the crystalline silicon may be carried out, for example, by chemical mechanical polishing and if necessary or desired, oxidizing the silicon followed by etching to the desired thickness of the silicon.

  7. Mask Roughness Induced LER in EUV Lithography

    E-Print Network [OSTI]

    McClinton, Brittany

    2011-01-01

    focus…………………………………… Alt-PSM……………………………………………………………… 5.2.122-nm……………………….. 5.2.2 Alt-PSM vs. Lines and Spaces at 22-Simplified LER, alt-psm……………………………… Simulated LER, 22nm alt-

  8. Virtual mask digital electron beam lithography

    DOE Patents [OSTI]

    Baylor, L.R.; Thomas, C.E.; Voelkl, E.; Moore, J.A.; Simpson, M.L.; Paulus, M.J.

    1999-04-06

    Systems and methods for direct-to-digital holography are described. An apparatus includes a laser; a beamsplitter optically coupled to the laser; a reference beam mirror optically coupled to the beamsplitter; an object optically coupled to the beamsplitter, a focusing lens optically coupled to both the reference beam mirror and the object; and a digital recorder optically coupled to the focusing lens. A reference beam is incident upon the reference beam mirror at a non-normal angle, and the reference beam and an object beam are focused by the focusing lens at a focal plane of the digital recorder to form an image. The systems and methods provide advantages in that computer assisted holographic measurements can be made. 5 figs.

  9. Virtual mask digital electron beam lithography

    DOE Patents [OSTI]

    Baylor, Larry R. (Farragut, TN); Thomas, Clarence E. (Knoxville, TN); Voelkl, Edgar (Oak Ridge, TN); Moore, James A. (Powell, TN); Simpson, Michael L. (Knoxville, TN); Paulus, Michael J. (Knoxville, TN)

    1999-01-01

    Systems and methods for direct-to-digital holography are described. An apparatus includes a laser; a beamsplitter optically coupled to the laser; a reference beam mirror optically coupled to the beamsplitter; an object optically coupled to the beamsplitter, a focusing lens optically coupled to both the reference beam mirror and the object; and a digital recorder optically coupled to the focusing lens. A reference beam is incident upon the reference beam mirror at a non-normal angle, and the reference beam and an object beam are focused by the focusing lens at a focal plane of the digital recorder to form an image. The systems and methods provide advantages in that computer assisted holographic measurements can be made.

  10. Extreme ultraviolet lithography machine

    DOE Patents [OSTI]

    Tichenor, Daniel A. (Castro Valley, CA); Kubiak, Glenn D. (Livermore, CA); Haney, Steven J. (Tracy, CA); Sweeney, Donald W. (San Ramon, CA)

    2000-01-01

    An extreme ultraviolet lithography (EUVL) machine or system for producing integrated circuit (IC) components, such as transistors, formed on a substrate. The EUVL machine utilizes a laser plasma point source directed via an optical arrangement onto a mask or reticle which is reflected by a multiple mirror system onto the substrate or target. The EUVL machine operates in the 10-14 nm wavelength soft x-ray photon. Basically the EUV machine includes an evacuated source chamber, an evacuated main or project chamber interconnected by a transport tube arrangement, wherein a laser beam is directed into a plasma generator which produces an illumination beam which is directed by optics from the source chamber through the connecting tube, into the projection chamber, and onto the reticle or mask, from which a patterned beam is reflected by optics in a projection optics (PO) box mounted in the main or projection chamber onto the substrate. In one embodiment of a EUVL machine, nine optical components are utilized, with four of the optical components located in the PO box. The main or projection chamber includes vibration isolators for the PO box and a vibration isolator mounting for the substrate, with the main or projection chamber being mounted on a support structure and being isolated.

  11. Method for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Felter, T. E. (Livermore, CA); Kubiak, Glenn D. (Livermore, CA)

    1999-01-01

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods.

  12. Method for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Felter, T. E. (727 Clara St., Livermore, Alameda County, CA 94550); Kubiak, G. D. (475 Maple St., Livermore, Alameda County, CA 94550)

    2000-01-01

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods.

  13. Maskless lithography

    DOE Patents [OSTI]

    Sweatt, William C. (Albuquerque, NM); Stulen, Richard H. (Livermore, CA)

    1999-01-01

    The present invention provides a method for maskless lithography. A plurality of individually addressable and rotatable micromirrors together comprise a two-dimensional array of micromirrors. Each micromirror in the two-dimensional array can be envisioned as an individually addressable element in the picture that comprises the circuit pattern desired. As each micromirror is addressed it rotates so as to reflect light from a light source onto a portion of the photoresist coated wafer thereby forming a pixel within the circuit pattern. By electronically addressing a two-dimensional array of these micromirrors in the proper sequence a circuit pattern that is comprised of these individual pixels can be constructed on a microchip. The reflecting surface of the micromirror is configured in such a way as to overcome coherence and diffraction effects in order to produce circuit elements having straight sides.

  14. Maskless lithography

    DOE Patents [OSTI]

    Sweatt, W.C.; Stulen, R.H.

    1999-02-09

    The present invention provides a method for maskless lithography. A plurality of individually addressable and rotatable micromirrors together comprise a two-dimensional array of micromirrors. Each micromirror in the two-dimensional array can be envisioned as an individually addressable element in the picture that comprises the circuit pattern desired. As each micromirror is addressed it rotates so as to reflect light from a light source onto a portion of the photoresist coated wafer thereby forming a pixel within the circuit pattern. By electronically addressing a two-dimensional array of these micromirrors in the proper sequence a circuit pattern that is comprised of these individual pixels can be constructed on a microchip. The reflecting surface of the micromirror is configured in such a way as to overcome coherence and diffraction effects in order to produce circuit elements having straight sides. 12 figs.

  15. Coatings on reflective mask substrates

    DOE Patents [OSTI]

    Tong, William Man-Wai (Oakland, CA); Taylor, John S. (Livermore, CA); Hector, Scott D. (Oakland, CA); Mangat, Pawitter J. S. (Gilbert, AZ); Stivers, Alan R. (San Jose, CA); Kofron, Patrick G. (San Jose, CA); Thompson, Matthew A. (Austin, TX)

    2002-01-01

    A process for creating a mask substrate involving depositing: 1) a coating on one or both sides of a low thermal expansion material EUVL mask substrate to improve defect inspection, surface finishing, and defect levels; and 2) a high dielectric coating, on the backside to facilitate electrostatic chucking and to correct for any bowing caused by the stress imbalance imparted by either other deposited coatings or the multilayer coating of the mask substrate. An film, such as TaSi, may be deposited on the front side and/or back of the low thermal expansion material before the material coating to balance the stress. The low thermal expansion material with a silicon overlayer and a silicon and/or other conductive underlayer enables improved defect inspection and stress balancing.

  16. Graphene nanoribbon superlattices fabricated via He ion lithography

    SciTech Connect (OSTI)

    Archanjo, Braulio S.; Fragneaud, Benjamin; Gustavo Cançado, Luiz; Winston, Donald; Miao, Feng; Alberto Achete, Carlos; Medeiros-Ribeiro, Gilberto

    2014-05-12

    Single-step nano-lithography was performed on graphene sheets using a helium ion microscope. Parallel “defect” lines of ?1??m length and ?5?nm width were written to form nanoribbon gratings down to 20?nm pitch. Polarized Raman spectroscopy shows that crystallographic orientation of the nanoribbons was partially maintained at their lateral edges, indicating a high-fidelity lithography process. Furthermore, Raman analysis of large exposure areas with different ion doses reveals that He ions produce point defects with radii ? 2× smaller than do Ga ions, demonstrating that scanning-He{sup +}-beam lithography can texture graphene with less damage.

  17. Maskless, resistless ion beam lithography

    SciTech Connect (OSTI)

    Ji, Qing

    2003-03-10

    As the dimensions of semiconductor devices are scaled down, in order to achieve higher levels of integration, optical lithography will no longer be sufficient for the needs of the semiconductor industry. Alternative next-generation lithography (NGL) approaches, such as extreme ultra-violet (EUV), X-ray, electron-beam, and ion projection lithography face some challenging issues with complicated mask technology and low throughput. Among the four major alternative NGL approaches, ion beam lithography is the only one that can provide both maskless and resistless patterning. As such, it can potentially make nano-fabrication much simpler. This thesis investigates a focused ion beam system for maskless, resistless patterning that can be made practical for high-volume production. In order to achieve maskless, resistless patterning, the ion source must be able to produce a variety of ion species. The compact FIB system being developed uses a multicusp plasma ion source, which can generate ion beams of various elements, such as O{sub 2}{sup +}, BF{sub 2}{sup +}, P{sup +} etc., for surface modification and doping applications. With optimized source condition, around 85% of BF{sub 2}{sup +}, over 90% of O{sub 2}{sup +} and P{sup +} have been achieved. The brightness of the multicusp-plasma ion source is a key issue for its application to maskless ion beam lithography. It can be substantially improved by optimizing the source configuration and extractor geometry. Measured brightness of 2 keV He{sup +} beam is as high as 440 A/cm{sup 2} {center_dot} Sr, which represents a 30x improvement over prior work. Direct patterning of Si thin film using a focused O{sub 2}{sup +} ion beam has been investigated. A thin surface oxide film can be selectively formed using 3 keV O{sub 2}{sup +} ions with the dose of 10{sup 15} cm{sup -2}. The oxide can then serve as a hard mask for patterning of the Si film. The process flow and the experimental results for directly patterned poly-Si features are presented. The formation of shallow pn-junctions in bulk silicon wafers by scanning focused P{sup +} beam implantation at 5 keV is also presented. With implantation dose of around 10{sup 16} cm{sup -2}, the electron concentration is about 2.5 x 10{sup 18} cm{sup -3} and electron mobility is around 200 cm{sup 2}/V{center_dot}s. To demonstrate the suitability of scanning FIB lithography for the manufacture of integrated circuit devices, SOI MOSFET fabrication using the maskless, resistless ion beam lithography is demonstrated. An array of microcolumns can be built by stacking multi-aperture electrode and insulator layers. Because the multicusp plasma source can achieve uniform ion density over a large area, it can be used in conjunction with the array of microcolumns, for massively parallel FIB processing to achieve reasonable exposure throughput.

  18. Method for the fabrication of three-dimensional microstructures by deep X-ray lithography

    DOE Patents [OSTI]

    Sweatt, William C.; Christenson, Todd R.

    2005-04-05

    A method for the fabrication of three-dimensional microstructures by deep X-ray lithography (DXRL) comprises a masking process that uses a patterned mask with inclined mask holes and off-normal exposures with a DXRL beam aligned with the inclined mask holes. Microstructural features that are oriented in different directions can be obtained by using multiple off-normal exposures through additional mask holes having different orientations. Various methods can be used to block the non-aligned mask holes from the beam when using multiple exposures. A method for fabricating a precision 3D X-ray mask comprises forming an intermediate mask and a master mask on a common support membrane.

  19. Nanopatterning of ultrananocrystalline diamond thin films via block copolymer lithography.

    SciTech Connect (OSTI)

    Ramanathan, M.; Darling, S. B.; Sumant, A. V.; Auciello, O.

    2010-07-01

    Nanopatterning of diamond surfaces is critical for the development of diamond-based microelectromechanical system/nanoelectromechanical system (MEMS/NEMS), such as resonators or switches. Micro-/nanopatterning of diamond materials is typically done using photolithography or electron beam lithography combined with reactive ion etching (RIE). In this work, we demonstrate a simple process, block copolymer (BCP) lithography, for nanopatterning of ultrananocrystalline diamond (UNCD) films to produce nanostructures suitable for the fabrication of NEMS based on UNCD. In BCP lithography, nanoscale self-assembled polymeric domains serve as an etch mask for pattern transfer. The authors used thin films of a cylinder-forming organic-inorganic BCP, poly(styrene-block-ferrocenyldimethylsilane), PS-b-PFS, as an etch mask on the surface of UNCD films. Orientational control of the etch masking cylindrical PFS blocks is achieved by manipulating the polymer film thickness in concert with the annealing treatment. We have observed that the surface roughness of UNCD layers plays an important role in transferring the pattern. Oxygen RIE was used to etch the exposed areas of the UNCD film underneath the BCP. Arrays of both UNCD posts and wirelike structures have been created using the same starting polymeric materials as the etch mask.

  20. Photoresist composition for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Felter, T. E. (Alameda County, CA); Kubiak, G. D. (Alameda County, CA)

    1999-01-01

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods. A photoresist composition for extreme ultraviolet radiation of boron carbide polymers, hydrochlorocarbons and mixtures thereof.

  1. Chains of quantum dot molecules grown on Si surface pre-patterned by ion-assisted nanoimprint lithography

    SciTech Connect (OSTI)

    Smagina, Zh. V.; Stepina, N. P., E-mail: stepina@isp.nsc.ru; Zinovyev, V. A.; Kuchinskaya, P. A. [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Lavrenteva 13, 630090 Novosibirsk (Russian Federation); Novikov, P. L.; Dvurechenskii, A. V. [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Lavrenteva 13, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova, 2, 630090 Novosibirsk (Russian Federation)

    2014-10-13

    An original approach based on the combination of nanoimprint lithography and ion irradiation through mask has been developed for fabrication of large-area periodical pattern on Si(100). Using the selective etching of regions amorphized by ion irradiation ordered structures with grooves and ridges were obtained. The shape and depth of the relief were governed by ion energy and by the number of etching stages as well. Laterally ordered chains of Ge quantum dots were fabricated by molecular beam epitaxy of Ge on the pre-patterned Si substrates. For small amount of Ge deposited chains contain separate quantum dot molecules. The increase of deposition amount leads to overlapping of quantum dot molecules with formation of dense homogeneous chains of quantum dots. It was shown that the residual irradiation-induced bulk defects underneath the grooves suppress nucleation of Ge islands at the bottom of grooves. On pre-patterned substrates with whole defect regions, etched quantum dots grow at the bottom of grooves. The observed location of Ge quantum dots is interpreted in terms of local strain-mediated surface chemical potential which controls the sites of islands nucleation. The local chemical potential is affected by additional strain formed by the residual defects. It was shown by molecular dynamics calculations that these defects form the compressive strain at the bottom of grooves.

  2. Contact thermal lithography

    E-Print Network [OSTI]

    Schmidt, Aaron Jerome, 1979-

    2004-01-01

    Contact thermal lithography is a method for fabricating microscale patterns using heat transfer. In contrast to photolithography, where the minimum achievable feature size is proportional to the wavelength of light used ...

  3. Automation of soft lithography

    E-Print Network [OSTI]

    Kim, Hyung-Jun

    2006-01-01

    This dissertation is a final documentation of the project whose goal is demonstrating manufacturability of soft lithography. Specifically, our target is creating micron scale patterns of resists on a 3 square inch, relatively ...

  4. M&A For Lithography Of Sparse Arrays Of Sub-Micrometer Features

    DOE Patents [OSTI]

    Brueck, Steven R.J. (Albuquerque, NM); Chen, Xiaolan (Albuquerque, NM); Zaidi, Saleem (Albuquerque, NM); Devine, Daniel J. (Los Gatos, CA)

    1998-06-02

    Methods and apparatuses are disclosed for the exposure of sparse hole and/or mesa arrays with line:space ratios of 1:3 or greater and sub-micrometer hole and/or mesa diameters in a layer of photosensitive material atop a layered material. Methods disclosed include: double exposure interferometric lithography pairs in which only those areas near the overlapping maxima of each single-period exposure pair receive a clearing exposure dose; double interferometric lithography exposure pairs with additional processing steps to transfer the array from a first single-period interferometric lithography exposure pair into an intermediate mask layer and a second single-period interferometric lithography exposure to further select a subset of the first array of holes; a double exposure of a single period interferometric lithography exposure pair to define a dense array of sub-micrometer holes and an optical lithography exposure in which only those holes near maxima of both exposures receive a clearing exposure dose; combination of a single-period interferometric exposure pair, processing to transfer resulting dense array of sub-micrometer holes into an intermediate etch mask, and an optical lithography exposure to select a subset of initial array to form a sparse array; combination of an optical exposure, transfer of exposure pattern into an intermediate mask layer, and a single-period interferometric lithography exposure pair; three-beam interferometric exposure pairs to form sparse arrays of sub-micrometer holes; five- and four-beam interferometric exposures to form a sparse array of sub-micrometer holes in a single exposure. Apparatuses disclosed include arrangements for the three-beam, five-beam and four-beam interferometric exposures.

  5. Electron Beam Lithography

    E-Print Network [OSTI]

    Sandini, Giulio

    Electron Beam Lithography Marco Salerno #12;Outline · general lithographic concepts · EBL www.cnf.cornell.edu/SPIEBook/SPIE1.HTM #12;Typical Electron Beam Column Zeiss GeminiTM column Types of Electron Beam Columns · no e- cross over no Boersch-effect (additional energy spread) · beam booster

  6. Tailoring Nanostructures Using Copolymer Nanoimprint Lithography

    E-Print Network [OSTI]

    Pascal Thebault; Stefan Niedermayer; Stefan Landis; Nicolas Chaix; Patrick Guenoun; Jean Daillant; Xingkun Man; David Andelman; Henri Orland

    2012-07-12

    Finding affordable ways of generating high-density ordered nanostructures that can be transferred to a substrate is a major challenge for industrial applications like memories or optical devices with high resolution features. In this work, we report on a novel technique to direct self-assembled structures of block copolymers by NanoImprint Lithography. Surface energy of a reusable mold and nanorheology are used to organize the copolymers in defect-free structures over tens of micrometers in size. Versatile and controlled in-plane orientations of about 25 nm half-period lamellar nanostructures are achieved and, in particular, include applications to circular tracks of magnetic reading heads.

  7. Tailoring Nanostructures Using Copolymer Nanoimprint Lithography

    E-Print Network [OSTI]

    Thebault, Pascal; Landis, Stefan; Chaix, Nicolas; Guenoun, Patrick; Daillant, Jean; Man, Xingkun; Andelman, David; Orland, Henri

    2012-01-01

    Finding affordable ways of generating high-density ordered nanostructures that can be transferred to a substrate is a major challenge for industrial applications like memories or optical devices with high resolution features. In this work, we report on a novel technique to direct self-assembled structures of block copolymers by NanoImprint Lithography. Surface energy of a reusable mold and nanorheology are used to organize the copolymers in defect-free structures over tens of micrometers in size. Versatile and controlled in-plane orientations of about 25 nm half-period lamellar nanostructures are achieved and, in particular, include applications to circular tracks of magnetic reading heads.

  8. Method and apparatus for inspecting an EUV mask blank

    DOE Patents [OSTI]

    Goldberg, Kenneth A.

    2005-11-08

    An apparatus and method for at-wavelength EUV mask-blank characterization for inspection of moderate and low spatial frequency coating uniformity using a synchrotron or other source of EUV light. The apparatus provides for rapid, non-destruction, non-contact, at-wavelength qualification of large mask areas, and can be self-calibrating or be calibrated to well-characterized reference samples. It can further check for spatial variation of mask reflectivity or for global differences among masks. The apparatus and method is particularly suited for inspection of coating uniformity and quality and can detect defects in the order of 50 .mu.m and above.

  9. Functional patterning of PDMS microfluidic devices using integrated chemo-masks

    E-Print Network [OSTI]

    Fraden, Seth

    .1039/c004050a Microfluidic devices can be molded easily from PDMS using soft lithography. However, it can be molded quickly, easily, and at low cost.1 Additional advantages of PDMS include its gas a cm-scale array at mm-scale precision, the photo-mask must be aligned with the microchannels to 1 part

  10. High numerical aperture projection system for extreme ultraviolet projection lithography

    DOE Patents [OSTI]

    Hudyma, Russell M. (San Ramon, CA)

    2000-01-01

    An optical system is described that is compatible with extreme ultraviolet radiation and comprises five reflective elements for projecting a mask image onto a substrate. The five optical elements are characterized in order from object to image as concave, convex, concave, convex, and concave mirrors. The optical system is particularly suited for ring field, step and scan lithography methods. The invention uses aspheric mirrors to minimize static distortion and balance the static distortion across the ring field width which effectively minimizes dynamic distortion. The present invention allows for higher device density because the optical system has improved resolution that results from the high numerical aperture, which is at least 0.14.

  11. Electroplating with Photoresist Masks

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    Electroplating with Photoresist Masks Revised: 2010-01-27 Source: www.microchemicals.eu e-Mail: sales@microchemicals.eu Electroplating - Basic Requirements on the Photoresist Electroplating with photoresist masks requires a chemically stable resist with a superior ad- hesion

  12. Soft x-ray reduction camera for submicron lithography

    DOE Patents [OSTI]

    Hawryluk, Andrew M. (2708 Rembrandt Pl., Modesto, CA 95356); Seppala, Lynn G. (7911 Mines Rd., Livermore, CA 94550)

    1991-01-01

    Soft x-ray projection lithography can be performed using x-ray optical components and spherical imaging lenses (mirrors), which form an x-ray reduction camera. The x-ray reduction is capable of projecting a 5x demagnified image of a mask onto a resist coated wafer using 4.5 nm radiation. The diffraction limited resolution of this design is about 135 nm with a depth of field of about 2.8 microns and a field of view of 0.2 cm.sup.2. X-ray reflecting masks (patterned x-ray multilayer mirrors) which are fabricated on thick substrates and can be made relatively distortion free are used, with a laser produced plasma for the source. Higher resolution and/or larger areas are possible by varying the optic figures of the components and source characteristics.

  13. Membrane projection lithography

    SciTech Connect (OSTI)

    Burckel, David Bruce; Davids, Paul S; Resnick, Paul J; Draper, Bruce L

    2015-03-17

    The various technologies presented herein relate to a three dimensional manufacturing technique for application with semiconductor technologies. A membrane layer can be formed over a cavity. An opening can be formed in the membrane such that the membrane can act as a mask layer to the underlying wall surfaces and bottom surface of the cavity. A beam to facilitate an operation comprising any of implantation, etching or deposition can be directed through the opening onto the underlying surface, with the opening acting as a mask to control the area of the underlying surfaces on which any of implantation occurs, material is removed, and/or material is deposited. The membrane can be removed, a new membrane placed over the cavity and a new opening formed to facilitate another implantation, etching, or deposition operation. By changing the direction of the beam different wall/bottom surfaces can be utilized to form a plurality of structures.

  14. Programmable imprint lithography template

    DOE Patents [OSTI]

    Cardinale, Gregory F. (Oakland, CA); Talin, Albert A. (Livermore, CA)

    2006-10-31

    A template for imprint lithography (IL) that reduces significantly template production costs by allowing the same template to be re-used for several technology generations. The template is composed of an array of spaced-apart moveable and individually addressable rods or plungers. Thus, the template can be configured to provide a desired pattern by programming the array of plungers such that certain of the plungers are in an "up" or actuated configuration. This arrangement of "up" and "down" plungers forms a pattern composed of protruding and recessed features which can then be impressed onto a polymer film coated substrate by applying a pressure to the template impressing the programmed configuration into the polymer film. The pattern impressed into the polymer film will be reproduced on the substrate by subsequent processing.

  15. Low-cost interference lithography

    E-Print Network [OSTI]

    Fucetola, Corey P.

    The authors report demonstration of a low-cost ( ? 1000 USD) interference lithography system based on a Lloyd’s mirror interferometer that is capable of ? 300?nm pitch patterning. The components include only a 405?nm GaN ...

  16. Feature filling modeling for step and flash imprint lithography Siddharth Chauhan, Frank Palmieri, Roger T. Bonnecaze,a

    E-Print Network [OSTI]

    : 10.1116/1.3147212 I. INTRODUCTION Step and flash imprint lithography SFIL is a low pres- sure molding technology of integrated circuits ICs , including high throughput and low defects, necessitate nearly perfect defect-free imprinting in SFIL. Complete filling of features during the imprint step is imperative

  17. Development of an immersion maskless lithography system

    E-Print Network [OSTI]

    Chao, David, Ph. D. Massachusetts Institute of Technology

    2005-01-01

    As lithography quickly approaches its limits with current technologies, a host of new ideas is being proposed in hopes of pushing lithography to new levels of performance. The work presented in this thesis explores the use ...

  18. Masked multichannel analyzer

    DOE Patents [OSTI]

    Winiecki, A.L.; Kroop, D.C.; McGee, M.K.; Lenkszus, F.R.

    1984-01-01

    An analytical instrument and particularly a time-of-flight-mass spectrometer for processing a large number of analog signals irregularly spaced over a spectrum, with programmable masking of portions of the spectrum where signals are unlikely in order to reduce memory requirements and/or with a signal capturing assembly having a plurality of signal capturing devices fewer in number than the analog signals for use in repeated cycles within the data processing time period.

  19. Masked multichannel analyzer

    DOE Patents [OSTI]

    Winiecki, Alan L. (Downers Grove, IL); Kroop, David C. (Columbia, MD); McGee, Marilyn K. (Colorado Springs, CO); Lenkszus, Frank R. (Woodridge, IL)

    1986-01-01

    An analytical instrument and particularly a time-of-flight-mass spectrometer for processing a large number of analog signals irregularly spaced over a spectrum, with programmable masking of portions of the spectrum where signals are unlikely in order to reduce memory requirements and/or with a signal capturing assembly having a plurality of signal capturing devices fewer in number than the analog signals for use in repeated cycles within the data processing time period.

  20. Critical illumination condenser for x-ray lithography

    DOE Patents [OSTI]

    Cohen, S.J.; Seppala, L.G.

    1998-04-07

    A critical illumination condenser system is disclosed, particularly adapted for use in extreme ultraviolet (EUV) projection lithography based on a ring field imaging system and a laser produced plasma source. The system uses three spherical mirrors and is capable of illuminating the extent of the mask plane by scanning either the primary mirror or the laser plasma source. The angles of radiation incident upon each mirror of the critical illumination condenser vary by less than eight (8) degrees. For example, the imaging system in which the critical illumination condenser is utilized has a 200 {micro}m source and requires a magnification of 26. The three spherical mirror system constitutes a two mirror inverse Cassegrain, or Schwarzschild configuration, with a 25% area obstruction (50% linear obstruction). The third mirror provides the final pupil and image relay. The mirrors include a multilayer reflective coating which is reflective over a narrow bandwidth. 6 figs.

  1. Critical illumination condenser for x-ray lithography

    DOE Patents [OSTI]

    Cohen, Simon J. (Pleasanton, CA); Seppala, Lynn G. (Livermore, CA)

    1998-01-01

    A critical illumination condenser system, particularly adapted for use in extreme ultraviolet (EUV) projection lithography based on a ring field imaging system and a laser produced plasma source. The system uses three spherical mirrors and is capable of illuminating the extent of the mask plane by scanning either the primary mirror or the laser plasma source. The angles of radiation incident upon each mirror of the critical illumination condenser vary by less than eight (8) degrees. For example, the imaging system in which the critical illumination condenser is utilized has a 200 .mu.m source and requires a magnification of 26.times.. The three spherical mirror system constitutes a two mirror inverse Cassegrain, or Schwarzschild configuration, with a 25% area obstruction (50% linear obstruction). The third mirror provides the final pupil and image relay. The mirrors include a multilayer reflective coating which is reflective over a narrow bandwidth.

  2. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, Melvin A. (Woodside, CA); Boyers, David G. (Mountain View, CA); Pincus, Cary (Sunnyvale, CA)

    1991-01-01

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and elminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an exellent moderate-priced X-ray source for lithography.

  3. Scattering with angular limitation projection electron beam lithography for suboptical lithography

    E-Print Network [OSTI]

    Harriott, Lloyd R.

    Scattering with angular limitation projection electron beam lithography for suboptical lithography era early in the next century. The scattering with angular limitation projection electron-beam lithography SCALPEL approach combines the high resolution and wide process latitude inherent in electron beam

  4. Photo-lithography of xanthate precursor poly(p-phenylenevinylene...

    Office of Scientific and Technical Information (OSTI)

    Conference: Photo-lithography of xanthate precursor poly(p-phenylenevinylene) polymers. Citation Details In-Document Search Title: Photo-lithography of xanthate precursor...

  5. Compact multi-bounce projection system for extreme ultraviolet projection lithography

    DOE Patents [OSTI]

    Hudyma, Russell M. (San Ramon, CA)

    2002-01-01

    An optical system compatible with short wavelength (extreme ultraviolet) radiation comprising four optical elements providing five reflective surfaces for projecting a mask image onto a substrate. The five optical surfaces are characterized in order from object to image as concave, convex, concave, convex and concave mirrors. The second and fourth reflective surfaces are part of the same optical element. The optical system is particularly suited for ring field step and scan lithography methods. The invention uses aspheric mirrors to minimize static distortion and balance the static distortion across the ring field width, which effectively minimizes dynamic distortion.

  6. Carbon contamination topography analysis of EUV masks

    E-Print Network [OSTI]

    Fan, Y.-J.

    2010-01-01

    mask surface. but also the topography of the contaminatedCarbon Contamination Topography Analysis of EUV Masks Yu-Jenpossible contamination topography. Lithographic simulations

  7. Extreme-UV lithography system

    DOE Patents [OSTI]

    Replogle, William C. (Livermore, CA); Sweatt, William C. (Albuquerque, NM)

    2001-01-01

    A photolithography system that employs a condenser that includes a series of aspheric mirrors on one side of a small, incoherent source of radiation producing a series of beams is provided. Each aspheric mirror images the quasi point source into a curved line segment. A relatively small arc of the ring image is needed by the camera; all of the beams are so manipulated that they all fall onto this same arc needed by the camera. Also, all of the beams are aimed through the camera's virtual entrance pupil. The condenser includes a correcting mirror for reshaping a beam segment which improves the overall system efficiency. The condenser efficiently fills the larger radius ringfield created by today's advanced camera designs. The system further includes (i) means for adjusting the intensity profile at the camera's entrance pupil or (ii) means for partially shielding the illumination imaging onto the mask or wafer. The adjusting means can, for example, change at least one of: (i) partial coherence of the photolithography system, (ii) mask image illumination uniformity on the wafer or (iii) centroid position of the illumination flux in the entrance pupil. A particularly preferred adjusting means includes at least one vignetting mask that covers at least a portion of the at least two substantially equal radial segments of the parent aspheric mirror.

  8. Extreme-UV lithography condenser

    DOE Patents [OSTI]

    Sweatt, William C. (Albuquerque, NM); Sweeney, Donald W. (San Ramon, CA); Shafer, David (Fairfield, CT); McGuire, James (Pasadena, CA)

    2001-01-01

    Condenser system for use with a ringfield camera in projection lithography where the condenser includes a series of segments of a parent aspheric mirror having one foci at a quasi-point source of radiation and the other foci at the radius of a ringfield have all but one or all of their beams translated and rotated by sets of mirrors such that all of the beams pass through the real entrance pupil of a ringfield camera about one of the beams and fall onto the ringfield radius as a coincident image as an arc of the ringfield. The condenser has a set of correcting mirrors with one of the correcting mirrors of each set, or a mirror that is common to said sets of mirrors, from which the radiation emanates, is a concave mirror that is positioned to shape a beam segment having a chord angle of about 25 to 85 degrees into a second beam segment having a chord angle of about 0 to 60 degrees.

  9. Scanning-helium-ion-beam lithography with hydrogen silsesquioxane resist

    E-Print Network [OSTI]

    Winston, Donald

    A scanning-helium-ion-beam microscope is now commercially available. This microscope can be used to perform lithography similar to, but of potentially higher resolution than, scanning electron-beam lithography. This article ...

  10. Sub-10-nm lithography with light-ion beams

    E-Print Network [OSTI]

    Winston, Donald, Ph. D. Massachusetts Institute of Technology

    2012-01-01

    Scanning-electron-beam lithography (SEBL) is the workhorse of nanoscale lithography in part because of the high brightness of the Schottky source of electrons, but also benefiting from decades of incremental innovation and ...

  11. Mask Edge Effects in Optical Lithography and Chip Level Modeling Methods

    E-Print Network [OSTI]

    Miller, Marshal

    2010-01-01

    Transmission for Chromeless PSM . Grating Based Experimentalvs. Duty Cycle for MoSi Att-PSM MoSi 0 th Order Transmissionfor MoSi Att-PSM . . . . . . . . . MoSi Compared to Ultra

  12. Residue-free fabrication of high-performance graphene devices by patterned PMMA stencil mask

    SciTech Connect (OSTI)

    Shih, Fu-Yu [Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China); Chen, Shao-Yu; Wu, Tsuei-Shin; Wang, Wei-Hua, E-mail: wwang@sinica.edu.tw [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China); Liu, Cheng-Hua; Chen, Yang-Fang [Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Ho, Po-Hsun; Chen, Chun-Wei [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2014-06-15

    Two-dimensional (2D) atomic crystals and their hybrid structures have recently attracted much attention due to their potential applications. The fabrication of metallic contacts or nanostructures on 2D materials is very common and generally achieved by performing electron-beam (e-beam) lithography. However, e-beam lithography is not applicable in certain situations, e.g., cases in which the e-beam resist does not adhere to the substrates or the intrinsic properties of the 2D materials are greatly altered and degraded. Here, we present a residue-free approach for fabricating high-performance graphene devices by patterning a thin film of e-beam resist as a stencil mask. This technique can be generally applied to substrates with varying surface conditions, while causing negligible residues on graphene. The technique also preserves the design flexibility offered by e-beam lithography and therefore allows us to fabricate multi-probe metallic contacts. The graphene field-effect transistors fabricated by this method exhibit smooth surfaces, high mobility, and distinct magnetotransport properties, confirming the advantages and versatility of the presented residue-free technique for the fabrication of devices composed of 2D materials.

  13. Condenser for ring-field deep-ultraviolet and extreme-ultraviolet lithography

    DOE Patents [OSTI]

    Chapman, Henry N. (Livermore, CA); Nugent, Keith A. (North Fitzroy, AU)

    2001-01-01

    A condenser for use with a ring-field deep ultraviolet or extreme ultraviolet lithography system. A condenser includes a ripple-plate mirror which is illuminated by a collimated beam at grazing incidence. The ripple plate comprises a plate mirror into which is formed a series of channels along an axis of the mirror to produce a series of concave surfaces in an undulating pattern. Light incident along the channels of the mirror is reflected onto a series of cones. The distribution of slopes on the ripple plate leads to a distribution of angles of reflection of the incident beam. This distribution has the form of an arc, with the extremes of the arc given by the greatest slope in the ripple plate. An imaging mirror focuses this distribution to a ring-field arc at the mask plane.

  14. Condenser for ring-field deep ultraviolet and extreme ultraviolet lithography

    DOE Patents [OSTI]

    Chapman, Henry N. (Livermore, CA); Nugent, Keith A. (North Fitzroy, AU)

    2002-01-01

    A condenser for use with a ring-field deep ultraviolet or extreme ultraviolet lithography system. A condenser includes a ripple-plate mirror which is illuminated by a collimated or converging beam at grazing incidence. The ripple plate comprises a flat or curved plate mirror into which is formed a series of channels along an axis of the mirror to produce a series of concave surfaces in an undulating pattern. Light incident along the channels of the mirror is reflected onto a series of cones. The distribution of slopes on the ripple plate leads to a distribution of angles of reflection of the incident beam. This distribution has the form of an arc, with the extremes of the arc given by the greatest slope in the ripple plate. An imaging mirror focuses this distribution to a ring-field arc at the mask plane.

  15. Demonstration of electronic pattern switching and 10x pattern demagnification in a maskless micro-ion beam reduction lithography system

    SciTech Connect (OSTI)

    Ngo, V.V.; Akker, B.; Leung, K.N.; Noh, I.; Scott, K.L.; Wilde, S.

    2002-05-31

    A proof-of-principle ion projection lithography (IPL) system called Maskless Micro-ion beam Reduction Lithography (MMRL) has been developed and tested at the Lawrence Berkeley National Laboratory (LBNL) for future integrated circuits (ICs) manufacturing and thin film media patterning [1]. This MMRL system is aimed at completely eliminating the first stage of the conventional IPL system [2] that contains the complicated beam optics design in front of the stencil mask and the mask itself. It consists of a multicusp RF plasma generator, a multi-beamlet pattern generator, and an all-electrostatic ion optical column. Results from ion beam exposures on PMMA and Shipley UVII-HS resists using 75 keV H+ are presented in this paper. Proof-of-principle electronic pattern switching together with 10x reduction ion optics (using a pattern generator made of nine 50-{micro}m switchable apertures) has been performed and is reported in this paper. In addition, the fabrication of a micro-fabricated pattern generator [3] on an SOI membrane is also presented.

  16. Nanofabrication on unconventional substrates using transferred hard masks

    E-Print Network [OSTI]

    Li, Luozhou

    A major challenge in nanofabrication is to pattern unconventional substrates that cannot be processed for a variety of reasons, such as incompatibility with spin coating, electron beam lithography, optical lithography, or ...

  17. Laser direct write system for fabricating seamless roll-to-roll lithography tools

    E-Print Network [OSTI]

    Petrzelka, Joseph E.

    Implementations of roll to roll contact lithography require new approaches towards manufacturing tooling, including stamps for roll to roll nanoimprint lithography (NIL) and soft lithography. Suitable roll based tools must ...

  18. Carbon contamination topography analysis of EUV masks

    E-Print Network [OSTI]

    Fan, Y.-J.

    2010-01-01

    induced carbon contamination of extreme ultraviolet optics,"and A. Izumi. "Carbon contamination of EL'V mask: filmEffect of Carbon Contamination on the Printing Performance

  19. Multilevel interference lithography--fabricating sub-wavelength periodic nanostructures

    E-Print Network [OSTI]

    Chang, Chih-Hao, 1980-

    2008-01-01

    Periodic nanostructures have many exciting applications, including high-energy spectroscopy, patterned magnetic media, photonic crystals, and templates for self-assembly. Interference lithography (IL) is an attractive ...

  20. Resolution Improvement and Pattern Generator Development for theMaskless Micro-Ion-Beam Reduction Lithography System

    SciTech Connect (OSTI)

    Jiang, Ximan

    2006-05-18

    The shrinking of IC devices has followed the Moore's Law for over three decades, which states that the density of transistors on integrated circuits will double about every two years. This great achievement is obtained via continuous advance in lithography technology. With the adoption of complicated resolution enhancement technologies, such as the phase shifting mask (PSM), the optical proximity correction (OPC), optical lithography with wavelength of 193 nm has enabled 45 nm printing by immersion method. However, this achievement comes together with the skyrocketing cost of masks, which makes the production of low volume application-specific IC (ASIC) impractical. In order to provide an economical lithography approach for low to medium volume advanced IC fabrication, a maskless ion beam lithography method, called Maskless Micro-ion-beam Reduction Lithography (MMRL), has been developed in the Lawrence Berkeley National Laboratory. The development of the prototype MMRL system has been described by Dr. Vinh Van Ngo in his Ph.D. thesis. But the resolution realized on the prototype MMRL system was far from the design expectation. In order to improve the resolution of the MMRL system, the ion optical system has been investigated. By integrating a field-free limiting aperture into the optical column, reducing the electromagnetic interference and cleaning the RF plasma, the resolution has been improved to around 50 nm. Computational analysis indicates that the MMRL system can be operated with an exposure field size of 0.25 mm and a beam half angle of 1.0 mrad on the wafer plane. Ion-ion interactions have been studied with a two-particle physics model. The results are in excellent agreement with those published by the other research groups. The charge-interaction analysis of MMRL shows that the ion-ion interactions must be reduced in order to obtain a throughput higher than 10 wafers per hour on 300-mm wafers. In addition, two different maskless lithography strategies have been studied. The dependence of the throughput with the exposure field size and the speed of the mechanical stage has been investigated. In order to perform maskless lithography, different micro-fabricated pattern generators have been developed for the MMRL system. Ion beamlet switching has been successfully demonstrated on the MMRL system. A positive bias voltage around 10 volts is sufficient to switch off the ion current on the micro-fabricated pattern generators. Some unexpected problems, such as the high-energy secondary electron radiations, have been discovered during the experimental investigation. Thermal and structural analysis indicates that the aperture displacement error induced by thermal expansion can satisfy the 3{delta} CD requirement for lithography nodes down to 25 nm. The cross-talking effect near the surface and inside the apertures of the pattern generator has been simulated in a 3-D ray-tracing code. New pattern generator design has been proposed to reduce the cross-talking effect. In order to eliminate the surface charging effect caused by the secondary electrons, a new beam-switching scheme in which the switching electrodes are immersed in the plasma has been demonstrated on a mechanically fabricated pattern generator.

  1. Ice Lithography for Nanodevices Dimitar Vlassarev,

    E-Print Network [OSTI]

    Golovchenko, Jene A.

    as a mask for lift-off without the device degradation and contamination associated with e-beam imaging-dimensional structures, through-resist mapping and registration of nanostructures, and simple, contamination-free removal, see Support- ing Information). Our sample consists of single-walled car- bon nanotubes (SWCNTs) grown

  2. Lithography DOI: 10.1002/anie.200703525

    E-Print Network [OSTI]

    Doyle, Patrick S.

    -up approaches such as polymer phase separation,[8] molecular self-assembly,[9] or colloidal assem- bly[10 performed by flood exposing a spin-coated layer of photo- resist film through a phase mask, thus imposing extruded shape using a variety of polymer precursors.[24] The method also provides the ability to finely

  3. Interference Assisted Lithography for Patterning of 1D Gridded Design

    E-Print Network [OSTI]

    Kahng, Andrew B.

    , USA 78750 3 University of California at San Diego, La Jolla, CA, USA 92093 4 Tela Innovations, Inc Assisted Lithography (IAL) as a promising and cost-effective solution for extending lithography. IAL for pattern splitting, as well as to address concerns of significantly increased patterning cost. Nano

  4. Multidimensional Simulation and Optimization of Hybrid Laser and Discharge Plasma Devices for EUV Lithography

    E-Print Network [OSTI]

    Harilal, S. S.

    advantages and disadvantages. In order to meet the requirements of the Intel Lithography Roadmap goals

  5. Free electron laser with masked chicane

    DOE Patents [OSTI]

    Nguyen, Dinh C. (Los Alamos, NM); Carlsten, Bruce E. (Los Alamos, NM)

    1999-01-01

    A free electron laser (FEL) is provided with an accelerator for outputting electron beam pulses; a buncher for modulating each one of the electron beam pulses to form each pulse into longitudinally dispersed bunches of electrons; and a wiggler for generating coherent light from the longitudinally dispersed bunches of electrons. The electron beam buncher is a chicane having a mask for physically modulating the electron beam pulses to form a series of electron beam bunches for input to the wiggler. In a preferred embodiment, the mask is located in the chicane at a position where each electron beam pulse has a maximum dispersion.

  6. Carbon contamination topography analysis of EUV masks

    SciTech Connect (OSTI)

    Fan, Y.-J.; Yankulin, L.; Thomas, P.; Mbanaso, C.; Antohe, A.; Garg, R.; Wang, Y.; Murray, T.; Wuest, A.; Goodwin, F.; Huh, S.; Cordes, A.; Naulleau, P.; Goldberg, K. A.; Mochi, I.; Gullikson, E.; Denbeaux, G.

    2010-03-12

    The impact of carbon contamination on extreme ultraviolet (EUV) masks is significant due to throughput loss and potential effects on imaging performance. Current carbon contamination research primarily focuses on the lifetime of the multilayer surfaces, determined by reflectivity loss and reduced throughput in EUV exposure tools. However, contamination on patterned EUV masks can cause additional effects on absorbing features and the printed images, as well as impacting the efficiency of cleaning process. In this work, several different techniques were used to determine possible contamination topography. Lithographic simulations were also performed and the results compared with the experimental data.

  7. OSIRIS Software: The Mask Designer Tool

    E-Print Network [OSTI]

    J. I. Gonzalez-Serrano; M. Sanchez-Portal; H. Castaneda; R. Quirk; E. D. de Miguel; M. Aguiar; J. Cepa

    2006-02-23

    OSIRIS is a Day One instrument that will be available at the 10m GTC telescope which is being built at La Palma observatory in the Canary Islands. This optical instrument is designed to obtain wide-field narrow-band images using tunable filters and to do low-resolution spectroscopy in both long-slit and multislit modes. For the multislit spectroscopy mode, we have developed a software to assist the observers to design focal plane masks. In this paper we describe the characteristics of this Mask Designer tool. We discuss the main design concepts, the functionality and particular features of the software.

  8. Lithography-driven design for manufacturing in nanometer- era VLSI

    E-Print Network [OSTI]

    Park, Chul-Hong

    2008-01-01

    I.5: Examples of phase shift mask: (a) alternating PSM, (b)attenuated PSM and (c) chromeless PSM. . . . . . . . . . . . . . . Figure I.6:

  9. 'The Final Struggle': The Art of the Soviet Death Mask

    E-Print Network [OSTI]

    Neumeyer, Joy

    2015-01-01

    methods, but the casting of death masks continued. 15 Theothers. 20 The process of casting a death mask has remainedtypical maximum window for casting is three days. With the

  10. Mask Aligner (Carl Suss MJB3)

    E-Print Network [OSTI]

    Subramanian, Venkat

    switches · Turn on the power supply unit · Flip switch on power supply unit and press "Lamp" on the power supply unit (allow 5 minutes to warm up) · Press "Power" on the mask aligner N2 CA PV power supply unit #12;Mode 1: Vacuum Contact (sub micron resolution) · Place wafer on chuck · Press the green "HP

  11. Metrology for electron-beam lithography and resist contrast at the sub-10 nm scale

    E-Print Network [OSTI]

    Duan, Huigao

    Exploring the resolution limit of electron-beam lithography is of great interest both scientifically and technologically. However, when electron-beam lithography approaches its resolution limit, imaging and metrology of ...

  12. High resolution imaging and lithography using interference of light and surface plasmon waves

    E-Print Network [OSTI]

    Kim, Yang-Hyo

    2007-01-01

    The resolution of optical imaging and lithography is limited by the wave nature of light. Studies have been undertaken to overcome the diffraction limit for imaging and lithography. In our lab, the standing wave surface ...

  13. Design and prototype : a manufacturing system for the soft lithography technique

    E-Print Network [OSTI]

    Cao, Arthur Y. (Arthur Yao)

    2006-01-01

    Ever since 1998 when the term "soft lithography" was first created, soft lithography techniques have drawn close attention of the academia and the industry. Micro contact printing is by far the most widely used soft ...

  14. The impact of reverberant self-masking and overlap-masking effects on speech intelligibility by cochlear implant listeners (L)

    E-Print Network [OSTI]

    Kokkinakis, Kostas; Loizou, Philipos C.

    2011-05-05

    The purpose of this study is to determine the relative impact of reverberant self-masking and overlap-masking effects on speech intelligibility by cochlear implant listeners. Sentences were presented in two conditions ...

  15. Translational-symmetry alternating phase shifting mask grating mark used in a linear measurement model of lithographic projection lens aberrations

    SciTech Connect (OSTI)

    Qiu Zicheng; Wang Xiangzhao; Bi Qunyu; Yuan Qiongyan; Peng Bo; Duan Lifeng

    2009-07-01

    A linear measurement model of lithographic projection lens aberrations is studied numerically based on the Hopkins theory of partially-coherent imaging and positive resist optical lithography (PROLITH) simulation. In this linearity model, the correlation between the mark's structure and its sensitivities to aberrations is analyzed. A method to design a mark with high sensitivity is proved and declared. By use of this method, a translational-symmetry alternating phase shifting mask (Alt-PSM) grating mark is redesigned with all of the even orders, {+-}3rd and {+-}5th order diffraction light missing. In the evaluation simulation, the measurement accuracies of aberrations prove to be enhanced apparently by use of the redesigned mark instead of the old ones.

  16. Geometry of nanopore devices fabricated by electron beam lithography: Simulations and experimental comparisons

    E-Print Network [OSTI]

    Nair, Sankar

    Geometry of nanopore devices fabricated by electron beam lithography: Simulations and experimental 2013 Keywords: Nanopore Simulation Electron beam lithography Penelope Nanotechnology Monte Carlo a b be fabricated by electron beam lithography (EBL) with high density (on the order of 10 devices per cm2

  17. Lithography and Design in Partnership: A New Roadmap Andrew B. Kahng

    E-Print Network [OSTI]

    Kahng, Andrew B.

    Lithography and Design in Partnership: A New Roadmap Andrew B. Kahng UCSD Departments of CSE roadmap' between lithography and design from several perspectives. First, we examine cultural gaps and other intrinsic barriers to a shared roadmap. Second, we discuss how lithography technol- ogy can change

  18. Microphotonic parabolic light directors fabricated by two-photon lithography

    SciTech Connect (OSTI)

    Atwater, Jackson H; Spinelli, P.; Kosten, Emily D; Parsons, J.; Van Lare, C; Van de Groep, J; Garcia de Abajo, J.; Polman, Albert; Atwater, Harry A.

    2011-01-01

    We have fabricated microphotonic parabolic light directors using two-photon lithography, thin-film processing, and aperture formation by focused ion beam lithography. Optical transmission measurements through upright parabolic directors 22 ?m high and 10 ?m in diameter exhibit strong beam directivity with a beam divergence of 5.6°, in reasonable agreement with ray-tracing and full-field electromagnetic simulations. The results indicate the suitability of microphotonic parabolic light directors for producing collimated beams for applications in advanced solar cell and light-emitting diode designs.

  19. Resolution Improvement and Pattern Generator Development for the Maskless Micro-Ion-Beam Reduction Lithography System

    E-Print Network [OSTI]

    Jiang, Ximan

    2006-01-01

    such as the phase shifting mask (PSM), the optical proximityCODE), phase shifting mask (PSM) and optical proximitylens. A phase shifting mask (PSM) also works in a similar

  20. Dose masking feature for BNCT radiotherapy planning

    DOE Patents [OSTI]

    Cook, Jeremy L. (Greeley, CO); Wessol, Daniel E. (Bozeman, MT); Wheeler, Floyd J. (Idaho Falls, ID)

    2000-01-01

    A system for displaying an accurate model of isodoses to be used in radiotherapy so that appropriate planning can be performed prior to actual treatment on a patient. The nature of the simulation of the radiotherapy planning for BNCT and Fast Neutron Therapy, etc., requires that the doses be computed in the entire volume. The "entire volume" includes the patient and beam geometries as well as the air spaces in between. Isodoses derived from the computed doses will therefore extend into the air regions between the patient and beam geometries and thus depict the unrealistic possibility that radiation deposition occurs in regions containing no physical media. This problem is solved by computing the doses for the entire geometry and then masking the physical and air regions along with the isodose contours superimposed over the patient image at the corresponding plane. The user is thus able to mask out (remove) the contour lines from the unwanted areas of the image by selecting the appropriate contour masking region from the raster image.

  1. Ultratech Develops an Improved Lithography Tool for LED Wafer Manufacturing

    Broader source: Energy.gov [DOE]

    Ultratech modified an existing lithography tool used for semiconductor manufacturing to better meet the cost and performance targets of the high-brightness LED manufacturing industry. The goal was to make the equipment compatible with the wide range of substrate diameters and thicknesses prevalent in the industry while reducing the capital cost and the overall cost of ownership (COO).

  2. Digital microfluidics using soft lithography{ John Paul Urbanski,a

    E-Print Network [OSTI]

    Amarasinghe, Saman

    Digital microfluidics using soft lithography{ John Paul Urbanski,a William Thies,b Christopher published as an Advance Article on the web 29th November 2005 DOI: 10.1039/b510127a Although microfluidic software to drive the pumps, valves, and electrodes used to manipulate fluids in microfluidic devices

  3. Ultrathin fluorinated diamondlike carbon coating for nanoimprint lithography imprinters

    E-Print Network [OSTI]

    Krchnavek, Robert R.

    Ultrathin fluorinated diamondlike carbon coating for nanoimprint lithography imprinters Ryan W-DLC is used as a NIL imprinter coating to provide this durable antiwear, antistick layer. Previous works10,11 have shown that DLC is a durable coating with a low surface energy 40 mJ/m2 . The fluorinated self

  4. Creating bio-inspired hierarchical 3D-2D photonic stacks via planar lithography on self-assembled inverse opals

    E-Print Network [OSTI]

    Ian B. Burgess; Joanna Aizenberg; Marko Loncar

    2012-11-29

    Structural hierarchy and complex 3D architecture are characteristics of biological photonic designs that are challenging to reproduce in synthetic materials. Top-down lithography allows for designer patterning of arbitrary shapes, but is largely restricted to planar 2D structures. Self-assembly techniques facilitate easy fabrication of 3D photonic crystals, but controllable defect-integration is difficult. In this paper we combine the advantages of top-down and bottom-up fabrication, developing two techniques to deposit 2D-lithographically-patterned planar layers on top of or in between inverse-opal 3D photonic crystals and creating hierarchical structures that resemble the architecture of the bright green wing scales of the butterfly, Parides sesostris. These fabrication procedures, combining advantages of both top-down and bottom-up fabrication, may prove useful in the development of omnidirectional coloration elements and 3D-2D photonic crystal devices.

  5. Creating bio-inspired hierarchical 3D-2D photonic stacks via planar lithography on self-assembled inverse opals

    E-Print Network [OSTI]

    Burgess, Ian B; Loncar, Marko

    2012-01-01

    Structural hierarchy and complex 3D architecture are characteristics of biological photonic designs that are challenging to reproduce in synthetic materials. Top-down lithography allows for designer patterning of arbitrary shapes, but is largely restricted to planar 2D structures. Self-assembly techniques facilitate easy fabrication of 3D photonic crystals, but controllable defect-integration is difficult. In this paper we combine the advantages of top-down and bottom-up fabrication, developing two techniques to deposit 2D-lithographically-patterned planar layers on top of or in between inverse-opal 3D photonic crystals and creating hierarchical structures that resemble the architecture of the bright green wing scales of the butterfly, Parides sesostris. These fabrication procedures, combining advantages of both top-down and bottom-up fabrication, may prove useful in the development of omnidirectional coloration elements and 3D-2D photonic crystal devices.

  6. Low Cost Lithography Tool for High Brightness LED Manufacturing

    SciTech Connect (OSTI)

    Andrew Hawryluk; Emily True

    2012-06-30

    The objective of this activity was to address the need for improved manufacturing tools for LEDs. Improvements include lower cost (both capital equipment cost reductions and cost-ofownership reductions), better automation and better yields. To meet the DOE objective of $1- 2/kilolumen, it will be necessary to develop these highly automated manufacturing tools. Lithography is used extensively in the fabrication of high-brightness LEDs, but the tools used to date are not scalable to high-volume manufacturing. This activity addressed the LED lithography process. During R&D and low volume manufacturing, most LED companies use contact-printers. However, several industries have shown that these printers are incompatible with high volume manufacturing and the LED industry needs to evolve to projection steppers. The need for projection lithography tools for LED manufacturing is identified in the Solid State Lighting Manufacturing Roadmap Draft, June 2009. The Roadmap states that Projection tools are needed by 2011. This work will modify a stepper, originally designed for semiconductor manufacturing, for use in LED manufacturing. This work addresses improvements to yield, material handling, automation and throughput for LED manufacturing while reducing the capital equipment cost.

  7. On the Cost of Lazy Engineering for Masked Software Implementations

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    On the Cost of Lazy Engineering for Masked Software Implementations Josep Balasch1 , Benedikt Engineering-ESAT/COSIC and iMinds Kasteelpark Arenberg 10, B-3001 Leuven-Heverlee, Belgium. 2 ICTEAM. As a result, implementing masking securely can be a time-consuming engineering problem. This is in strong

  8. Nodal photolithography : lithography via far-field optical nodes in the resist

    E-Print Network [OSTI]

    Winston, Donald, S.M. Massachusetts Institute of Technology

    2008-01-01

    In this thesis, I investigate one approach - stimulated emission depletion - to surmounting the diffraction limitation of optical lithography. This approach uses farfield optical nodes to orchestrate reversible, saturable ...

  9. Development of a microfluidic device for patterning multiple species by scanning probe lithography 

    E-Print Network [OSTI]

    Rivas Cardona, Juan Alberto

    2009-06-02

    Scanning Probe Lithography (SPL) is a versatile nanofabrication platform that leverages microfluidic “ink” delivery systems with Scanning Probe Microscopy (SPM) for generating surface-patterned chemical functionality on ...

  10. Optical method and apparatus for detection of surface and near-subsurface defects in dense ceramics

    DOE Patents [OSTI]

    Ellingson, W.A.; Brada, M.P.

    1995-06-20

    A laser is used in a non-destructive manner to detect surface and near-subsurface defects in dense ceramics and particularly in ceramic bodies with complex shapes such as ceramic bearings, turbine blades, races, and the like. The laser`s wavelength is selected based upon the composition of the ceramic sample and the laser can be directed on the sample while the sample is static or in dynamic rotate or translate motion. Light is scattered off surface and subsurface defects using a preselected polarization. The change in polarization angle is used to select the depth and characteristics of surface/subsurface defects. The scattered light is detected by an optical train consisting of a charge coupled device (CCD), or vidicon, television camera which, in turn, is coupled to a video monitor and a computer for digitizing the image. An analyzing polarizer in the optical train allows scattered light at a given polarization angle to be observed for enhancing sensitivity to either surface or near-subsurface defects. Application of digital image processing allows subtraction of digitized images in near real-time providing enhanced sensitivity to subsurface defects. Storing known ``feature masks`` of identified defects in the computer and comparing the detected scatter pattern (Fourier images) with the stored feature masks allows for automatic classification of detected defects. 29 figs.

  11. Optical method and apparatus for detection of surface and near-subsurface defects in dense ceramics

    DOE Patents [OSTI]

    Ellingson, William A. (Naperville, IL); Brada, Mark P. (Goleta, CA)

    1995-01-01

    A laser is used in a non-destructive manner to detect surface and near-subsurface defects in dense ceramics and particularly in ceramic bodies with complex shapes such as ceramic bearings, turbine blades, races, and the like. The laser's wavelength is selected based upon the composition of the ceramic sample and the laser can be directed on the sample while the sample is static or in dynamic rotate or translate motion. Light is scattered off surface and subsurface defects using a preselected polarization. The change in polarization angle is used to select the depth and characteristics of surface/subsurface defects. The scattered light is detected by an optical train consisting of a charge coupled device (CCD), or vidicon, television camera which, in turn, is coupled to a video monitor and a computer for digitizing the image. An analyzing polarizer in the optical train allows scattered light at a given polarization angle to be observed for enhancing sensitivity to either surface or near-subsurface defects. Application of digital image processing allows subtraction of digitized images in near real-time providing enhanced sensitivity to subsurface defects. Storing known "feature masks" of identified defects in the computer and comparing the detected scatter pattern (Fourier images) with the stored feature masks allows for automatic classification of detected defects.

  12. Low thermal distortion extreme-UV lithography reticle

    DOE Patents [OSTI]

    Gianoulakis, Steven E. (Albuquerque, NM); Ray-Chaudhuri, Avijit K. (Livermore, CA)

    2001-01-01

    Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.

  13. Low thermal distortion extreme-UV lithography reticle

    DOE Patents [OSTI]

    Gianoulakis, Steven E. (Albuquerque, NM); Ray-Chaudhuri, Avijit K. (Livermore, CA)

    2002-01-01

    Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.

  14. Low thermal distortion Extreme-UV lithography reticle and method

    DOE Patents [OSTI]

    Gianoulakis, Steven E. (Albuquerque, NM); Ray-Chaudhuri, Avijit K. (Livermore, CA)

    2002-01-01

    Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.

  15. Plastic masters--rigid templates for soft lithography Salil P. Desai,a

    E-Print Network [OSTI]

    Voldman, Joel

    Plastic masters--rigid templates for soft lithography Salil P. Desai,a Dennis M. Freemanab and Joel plastic master molds for soft lithography directly from (poly)dimethysiloxane devices. Plastics masters without the need for cleanroom facilities. We have successfully demonstrated the use of plastics

  16. A microfluidic microbial fuel cell fabricated by soft lithography Fang Qian a,b,

    E-Print Network [OSTI]

    A microfluidic microbial fuel cell fabricated by soft lithography Fang Qian a,b, , Zhen He c microfluidic microbial fuel cell (MFC) platform built by soft-lithography tech- niques. The MFC design includes a unique sub-5 lL polydimethylsiloxane soft chamber featuring carbon cloth electrodes and microfluidic

  17. Multilayer resist methods for nanoimprint lithography on nonflat surfaces Xiaoyun Sun, Lei Zhuang,a)

    E-Print Network [OSTI]

    American Vacuum Society. S0734-211X 98 10106-3 I. INTRODUCTION Nanoimprint lithography NIL , a new approach of modifying the resist's chemical properties with radiation as in conventional lithography.1 NIL has issue for NIL to become a major li- thography tool is to imprint on nonflat surfaces. This article

  18. Low-cost method for producing extreme ultraviolet lithography optics

    DOE Patents [OSTI]

    Folta, James A. (Livermore, CA); Montcalm, Claude (Fort Collins, CO); Taylor, John S. (Livermore, CA); Spiller, Eberhard A. (Mt. Kisco, NY)

    2003-11-21

    Spherical and non-spherical optical elements produced by standard optical figuring and polishing techniques are extremely expensive. Such surfaces can be cheaply produced by diamond turning; however, the roughness in the diamond turned surface prevent their use for EUV lithography. These ripples are smoothed with a coating of polyimide before applying a 60 period Mo/Si multilayer to reflect a wavelength of 134 .ANG. and have obtained peak reflectivities close to 63%. The savings in cost are about a factor of 100.

  19. Quantum lithography with classical light: Generation of arbitrary patterns 

    E-Print Network [OSTI]

    Sun, Qingqing; Hemmer, Philip R.; Zubairy, M. Suhail

    2007-01-01

    stream_source_info PhysRevA.75.065803.pdf.txt stream_content_type text/plain stream_size 16287 Content-Encoding ISO-8859-1 stream_name PhysRevA.75.065803.pdf.txt Content-Type text/plain; charset=ISO-8859-1 Quantum... alternative meth- ods based on classical fields ?9?11?. In Ref. ?12?, a novel approach was proposed to implement quantum lithography using the classical light. This is accom- plished by correlating wave vector and frequency in a narrow band multiphoton...

  20. Mask-assisted seeded growth of segmented metallic heteronanostructures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Crane, Cameron C. [Univ. of Arkansas, Fayetteville, AR (United States); Tao, Jing [Brookhaven National Lab. (BNL), Upton, NY (United States); Wang, Feng [Univ. of Arkansas, Fayetteville, AR (United States); Zhu, Yimei [Brookhaven National Lab. (BNL), Upton, NY (United States); Chen, Jingyi [Univ. of Arkansas, Fayetteville, AR (United States)

    2014-12-04

    Controlling the deposition of exotic metals in the seeded growth of multi-metal nanostructures is challenging. This work describes a seeded growth method assisted by a mask for synthesis of segmented binary or ternary metal nanostructures. Silica is used as a mask to partially block the surface of a seed and a second metal is subsequently deposited on the exposed area, forming a bimetallic heterodimer. The initial demonstration was carried out on a Au seed, followed by deposition of Pd or Pt on the seed. It was found that Pd tends to spread out laterally on the seed while Pt inclines to grow vertically into branched topology on Au. Without removal of the SiO? mask, Pt could be further deposited on the unblocked Pd of the Pd-Au dimer to form a Pt-Pd-Au trimer. The mask-assisted seeded growth provides a general strategy to construct segmented metallic nanoarchitectures.

  1. Mask-assisted seeded growth of segmented metallic heteronanostructures

    SciTech Connect (OSTI)

    Crane, Cameron C.; Tao, Jing; Wang, Feng; Zhu, Yimei; Chen, Jingyi

    2014-11-24

    Controlling the deposition of exotic metals in the seeded growth of multi-metal nanostructures is challenging. This work describes a seeded growth method assisted by a mask for synthesis of segmented binary or ternary metal nanostructures. Silica is used as a mask to partially block the surface of a seed and a second metal is subsequently deposited on the exposed area, forming a bimetallic heterodimer. The initial demonstration was carried out on a Au seed, followed by deposition of Pd or Pt on the seed. It was found that Pd tends to spread out laterally on the seed while Pt inclines to grow vertically into branched topology on Au. Without removal of the SiO? mask, Pt could be further deposited on the unblocked Pd of the Pd-Au dimer to form a Pt-Pd-Au trimer. The mask-assisted seeded growth provides a general strategy to construct segmented metallic nanoarchitectures.

  2. Mask-Assisted Seeded Growth of Segmented Metallic Heteronanostructures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Crane, Cameron C.; Tao, Jing; Wang, Feng; Zhu, Yimei; Chen, Jingyi

    2014-12-04

    Controlling the deposition of exotic metals in the seeded growth of multi-metal nanostructures is challenging. This work describes a seeded growth method assisted by a mask for synthesis of segmented binary or ternary metal nanostructures. Silica is used as a mask to partially block the surface of a seed and a second metal is subsequently deposited on the exposed area, forming a bimetallic heterodimer. The initial demonstration was carried out on a Au seed, followed by deposition of Pd or Pt on the seed. It was found that Pd tends to spread out laterally on the seed while Pt inclinesmore »to grow vertically into branched topology on Au. Without removal of the SiO? mask, Pt could be further deposited on the unblocked Pd of the Pd-Au dimer to form a Pt-Pd-Au trimer. The mask-assisted seeded growth provides a general strategy to construct segmented metallic nanoarchitectures.« less

  3. Mask-Assisted Seeded Growth of Segmented Metallic Heteronanostructures

    SciTech Connect (OSTI)

    Crane, Cameron C.; Tao, Jing; Wang, Feng; Zhu, Yimei; Chen, Jingyi

    2014-12-04

    Controlling the deposition of exotic metals in the seeded growth of multi-metal nanostructures is challenging. This work describes a seeded growth method assisted by a mask for synthesis of segmented binary or ternary metal nanostructures. Silica is used as a mask to partially block the surface of a seed and a second metal is subsequently deposited on the exposed area, forming a bimetallic heterodimer. The initial demonstration was carried out on a Au seed, followed by deposition of Pd or Pt on the seed. It was found that Pd tends to spread out laterally on the seed while Pt inclines to grow vertically into branched topology on Au. Without removal of the SiO? mask, Pt could be further deposited on the unblocked Pd of the Pd-Au dimer to form a Pt-Pd-Au trimer. The mask-assisted seeded growth provides a general strategy to construct segmented metallic nanoarchitectures.

  4. Bubble masks for time-encoded imaging of fast neutrons.

    SciTech Connect (OSTI)

    Brubaker, Erik; Brennan, James S.; Marleau, Peter; Nowack, Aaron B.; Steele, John; Sweany, Melinda; Throckmorton, Daniel J.

    2013-09-01

    Time-encoded imaging is an approach to directional radiation detection that is being developed at SNL with a focus on fast neutron directional detection. In this technique, a time modulation of a detected neutron signal is induced-typically, a moving mask that attenuates neutrons with a time structure that depends on the source position. An important challenge in time-encoded imaging is to develop high-resolution two-dimensional imaging capabilities; building a mechanically moving high-resolution mask presents challenges both theoretical and technical. We have investigated an alternative to mechanical masks that replaces the solid mask with a liquid such as mineral oil. Instead of fixed blocks of solid material that move in pre-defined patterns, the oil is contained in tubing structures, and carefully introduced air gaps-bubbles-propagate through the tubing, generating moving patterns of oil mask elements and air apertures. Compared to current moving-mask techniques, the bubble mask is simple, since mechanical motion is replaced by gravity-driven bubble propagation; it is flexible, since arbitrary bubble patterns can be generated by a software-controlled valve actuator; and it is potentially high performance, since the tubing and bubble size can be tuned for high-resolution imaging requirements. We have built and tested various single-tube mask elements, and will present results on bubble introduction and propagation as a function of tubing size and cross-sectional shape; real-time bubble position tracking; neutron source imaging tests; and reconstruction techniques demonstrated on simple test data as well as a simulated full detector system.

  5. MASKS 2004 Invitation to 3D vision Step-by-Step Model Buidling

    E-Print Network [OSTI]

    Kosecka, Jana

    MASKS © 2004 Invitation to 3D vision Step-by-Step Model Buidling #12;MASKS © 2004 Invitation to 3D Reconstruction Sparse Structure and camera motion Landing Augmented Reality Vision Based Control #12;MASKS © 2004 Reconstruction #12;MASKS © 2004 Invitation to 3D vision Review Feature correspondence Projective Reconstruction

  6. Coma measurement by use of an alternating phase-shifting mask mark with a specific phase width

    SciTech Connect (OSTI)

    Qiu Zicheng; Wang Xiangzhao; Yuan Qiongyan; Wang Fan

    2009-01-10

    The correlation between the coma sensitivity of the alternating phase-shifting mask (Alt-PSM) mark and the mark's structure is studied based on the Hopkins theory of partially coherent imaging and positive resist optical lithography (PROLITH) simulation. It is found that an optimized Alt-PSM mark with its phase width being two-thirds its pitch has a higher sensitivity to coma than Alt-PSM marks with the same pitch and the different phase widths. The pitch of the Alt-PSM mark is also optimized by PROLITH simulation, and the structure of p=1.92{lambda}/NA and pw=2p/3 proves to be with the highest sensitivity. The optimized Alt-PSM mark is used as a measurement mark to retrieve coma aberration from the projection optics in lithographic tools. In comparison with an ordinary Alt-PSM mark with its phase width being a half its pitch, the measurement accuracies of Z7 and Z14 apparently increase.

  7. Development of ion sources for ion projection lithography

    SciTech Connect (OSTI)

    Lee, Y.; Gough, R.A.; Kunkel, W.B.; Leung, K.N.; Perkins, L.T.

    1996-05-01

    Multicusp ion sources are capable of generating ion beams with low axial energy spread as required by the Ion Projection Lithography (IPL). Longitudinal ion energy spread has been studied in two different types of plasma discharge: the filament discharge ion source characterized by its low axial energy spread, and the RF-driven ion source characterized by its long source lifetime. For He{sup +} ions, longitudinal ion energy spreads of 1-2 eV were measured for a filament discharge multicusp ion source which is within the IPL device requirements. Ion beams with larger axial energy spread were observed in the RF-driven source. A double-chamber ion source has been designed which combines the advantages of low axial energy spread of the filament discharge ion source with the long lifetime of the RF-driven source. The energy spread of the double chamber source is lower than that of the RF-driven source.

  8. Method for the protection of extreme ultraviolet lithography optics

    DOE Patents [OSTI]

    Grunow, Philip A.; Clift, Wayne M.; Klebanoff, Leonard E.

    2010-06-22

    A coating for the protection of optical surfaces exposed to a high energy erosive plasma. A gas that can be decomposed by the high energy plasma, such as the xenon plasma used for extreme ultraviolet lithography (EUVL), is injected into the EUVL machine. The decomposition products coat the optical surfaces with a protective coating maintained at less than about 100 .ANG. thick by periodic injections of the gas. Gases that can be used include hydrocarbon gases, particularly methane, PH.sub.3 and H.sub.2S. The use of PH.sub.3 and H.sub.2S is particularly advantageous since films of the plasma-induced decomposition products S and P cannot grow to greater than 10 .ANG. thick in a vacuum atmosphere such as found in an EUVL machine.

  9. The development of a prototype Zone-Plate-Array Lithography (ZPAL) system

    E-Print Network [OSTI]

    Patel, Amil Ashok, 1979-

    2004-01-01

    The research presented in this paper aims to build a Zone-Plate-Array Lithography (ZPAL) prototype tool that will demonstrate the high-resolution, parallel patterning capabilities of the architecture. The experiment will ...

  10. Modeling the point-spread function in helium-ion lithography

    E-Print Network [OSTI]

    Winston, Donald

    We present here a hybrid approach to modeling helium-ion lithography that combines the power and ease-of-use of the Stopping and Range of Ions in Matter (SRIM) software with the results of recent work simulating secondary ...

  11. Resolution Limits of Electron-Beam Lithography toward the Atomic Scale

    E-Print Network [OSTI]

    Zhang, Lihua

    We investigated electron-beam lithography with an aberration-corrected scanning transmission electron microscope. We achieved 2 nm isolated feature size and 5 nm half-pitch in hydrogen silsesquioxane resist. We also analyzed ...

  12. Development of a simple, compact, low-cost interference lithography system

    E-Print Network [OSTI]

    Korre, Hasan

    Interference lithography (IL) has proven itself to be an enabling technology for nanofabrication. Within IL, issues of spatial phase distortion, fringe stability, and substrate development have been explored and addressed. ...

  13. Limiting factors in sub-10 nm scanning-electron-beam lithography

    E-Print Network [OSTI]

    Berggren, Karl K.

    Achieving the highest possible resolution using scanning-electron-beam lithography (SEBL) has become an increasingly urgent problem in recent years, as advances in various nanotechnology applications [ F. S. Bates and G. ...

  14. Understanding of hydrogen silsesquioxane electron resist for sub-5-nm-half-pitch lithography

    E-Print Network [OSTI]

    Berggren, Karl K.

    The authors, demonstrated that 4.5-nm-half-pitch structures could be achieved using electron-beam lithography, followed by salty development. They also hypothesized a development mechanism for hydrogen silsesquioxane, ...

  15. Large area high density quantized magnetic disks fabricated using nanoimprint lithography

    E-Print Network [OSTI]

    for fabricating large area quantized magnetic disks QMDs using nanoimprint lithography NIL , electroplating or a via array. The other is that for high resolution an antireflection coating ARC layer is needed, which

  16. Contact region fidelity, sensitivity, and control in roll-based soft lithography

    E-Print Network [OSTI]

    Petrzelka, Joseph E

    2012-01-01

    Soft lithography is a printing process that uses small features on an elastomeric stamp to transfer micron and sub-micron patterns to a substrate. Translating this lab scale process to a roll-based manufacturing platform ...

  17. Nanometer-precision electron-beam lithography with applications in integrated optics

    E-Print Network [OSTI]

    Hastings, Jeffrey Todd, 1975-

    2003-01-01

    Scanning electron-beam lithography (SEBL) provides sub-10-nm resolution and arbitrary-pattern generation; however, SEBL's pattern-placement accuracy remains inadequate for future integrated-circuits and integrated-optical ...

  18. Affine Defects and Gravitation

    E-Print Network [OSTI]

    R. J. Petti

    2014-12-12

    We argue that the structure general relativity (GR) as a theory of affine defects is deeper than the standard interpretation as a metric theory of gravitation. Einstein-Cartan theory (EC), with its inhomogenous affine symmetry, should be the standard-bearer for GR-like theories. A discrete affine interpretation of EC (and gauge theory) yields topological definitions of momentum and spin (and Yang Mills current), and their conservation laws become discrete topological identities. Considerations from quantum theory provide evidence that discrete affine defects are the physical foundation for gravitation.

  19. System for generating two-dimensional masks from a three-dimensional model using topological analysis

    DOE Patents [OSTI]

    Schiek, Richard (Albuquerque, NM)

    2006-06-20

    A method of generating two-dimensional masks from a three-dimensional model comprises providing a three-dimensional model representing a micro-electro-mechanical structure for manufacture and a description of process mask requirements, reducing the three-dimensional model to a topological description of unique cross sections, and selecting candidate masks from the unique cross sections and the cross section topology. The method further can comprise reconciling the candidate masks based on the process mask requirements description to produce two-dimensional process masks.

  20. Fabrication of ZnO photonic crystals by nanosphere lithography using inductively coupled-plasma reactive ion etching with CH{sub 4}/H{sub 2}/Ar plasma on the ZnO/GaN heterojunction light emitting diodes

    SciTech Connect (OSTI)

    Chen, Shr-Jia; Chang, Chun-Ming; Kao, Jiann-Shiun; Chen, Fu-Rong; Tsai, Chuen-Horng [Engineering and System Science, National Tsing Hua University, Hsinchu, 30013 Taiwan (China); Instrument Technology Research Center, National Applied Research Laboratories, Hsinchu, 300 Taiwan (China); Engineering and System Science, National Tsing Hua University, Hsinchu, 30013 Taiwan (China)

    2010-07-15

    This article reports fabrication of n-ZnO photonic crystal/p-GaN light emitting diode (LED) by nanosphere lithography to further booster the light efficiency. In this article, the fabrication of ZnO photonic crystals is carried out by nanosphere lithography using inductively coupled plasma reactive ion etching with CH{sub 4}/H{sub 2}/Ar plasma on the n-ZnO/p-GaN heterojunction LEDs. The CH{sub 4}/H{sub 2}/Ar mixed gas gives high etching rate of n-ZnO film, which yields a better surface morphology and results less plasma-induced damages of the n-ZnO film. Optimal ZnO lattice parameters of 200 nm and air fill factor from 0.35 to 0.65 were obtained from fitting the spectrum of n-ZnO/p-GaN LED using a MATLAB code. In this article, we will show our recent result that a ZnO photonic crystal cylinder has been fabricated using polystyrene nanosphere mask with lattice parameter of 200 nm and radius of hole around 70 nm. Surface morphology of ZnO photonic crystal was examined by scanning electron microscope.

  1. Motivation Defect correction The algorithm Summary Defect correction in optimization

    E-Print Network [OSTI]

    Hemker, P.W.

    Motivation Defect correction The algorithm Summary Defect correction in optimization "Manifold Mapping" P.W. Hemker IPIR/CWI/UvA June 11, 2010 Manifold Mapping P.W. Hemker #12;Motivation Defect correction The algorithm Summary Motivation Motivation determine x1, x2, x1, x3, x4, x5, x6, x7 Manifold

  2. Ga lithography in sputtered niobium for superconductive micro and nanowires

    SciTech Connect (OSTI)

    Henry, M. David; Wolfley, Steve; Monson, Todd; Lewis, Rupert

    2014-08-18

    This work demonstrates the use of focused ion beam (FIB) implanted Ga as a lithographic mask for plasma etching of Nb films. Using a highly collimated Ga beam of a FIB, Nb is implanted 12?nm deep with a 14?nm thick Ga layer providing etch selectivity better than 15:1 with fluorine based etch chemistry. Implanted square test patterns, both 10??m by 10??m and 100??m by 100??m, demonstrate that doses above than 7.5?×?10{sup 15?}cm{sup ?2} at 30?kV provide adequate mask protection for a 205?nm thick, sputtered Nb film. The resolution of this dry lithographic technique is demonstrated by fabrication of nanowires 75?nm wide by 10??m long connected to 50??m wide contact pads. The residual resistance ratio of patterned Nb films was 3. The superconducting transition temperature (T{sub c})?=?7.7?K was measured using a magnetic properties measurement system. This nanoscale, dry lithographic technique was extended to sputtered TiN and Ta here and could be used on other fluorine etched superconductors such as NbN, NbSi, and NbTi.

  3. Simultaneous Feature Extraction and Selection Using a Masking Genetic Algorithm

    E-Print Network [OSTI]

    1 Simultaneous Feature Extraction and Selection Using a Masking Genetic Algorithm Michael L. Raymer: identification of functional water molecules bound to protein surfaces, and diagnosis of thyroid deficiency of feature extraction ­ defining new features in terms of the original feature set to facilitate more

  4. Mask Making in the NanoLab (Optical Pattern Generator)

    E-Print Network [OSTI]

    California at Irvine, University of

    design or arcs. Pattern Generator charge: $40.80/hour. There is a minimum 30 minute pattern generatorMask Making in the NanoLab (Optical Pattern Generator) Layout To submit a design, use any CAD software which generates a GDS, TDB or CIF file. GDS and TDB files need to be converted for the pattern

  5. ORIGINAL PAPER Vibration detection and discrimination in the masked birch

    E-Print Network [OSTI]

    Yack, Jayne E.

    ORIGINAL PAPER Vibration detection and discrimination in the masked birch caterpillar (Drepana-Verlag 2012 Abstract Leaf-borne vibrations are potentially important to caterpillars for communication they detect and discriminate between vibrations from relevant and non-relevant sources. We measured

  6. Affine Masking against Higher-Order Side Channel Analysis

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    the side channel leakage (e.g. the power consumption, the electromagnetic emana- tions) produced during variable is independent of any sensitive variable. This strategy ensures that the instantaneous leakage is independent of any sensitive variable, thus rendering SCA difficult to perform. The masking can

  7. Analysis of Optics and Mask Contamination in SEMATECH EUV Micro-Exposure Tools

    E-Print Network [OSTI]

    Wuest, Andrea

    2008-01-01

    Analysis of Optics and Mask Contamination in SEMATECHMioro^Exposure Tools IEUVI Optics Contamination/Lifetime TWG

  8. Extreme ultraviolet laser-based table-top aerial image metrology of lithographic masks

    E-Print Network [OSTI]

    Rocca, Jorge J.

    masks," in 22nd Annual BACUS Symposium on Photomask Techology, (proceedings of SPIE, 2002), 0277­0786X

  9. A next-generation EUV Fresnel zoneplate mask-imaging microscope

    E-Print Network [OSTI]

    Goldberg, Kenneth A.

    2012-01-01

    A next-generation EUV Fresnel zoneplate mask-imaginghigh-magnification all-EUV Fresnel zoneplate microscope, the

  10. Proceedings of NAMRI/SME, Vol. 39, 2011 Additive Manufacturing based on Optimized Mask Video

    E-Print Network [OSTI]

    Chen, Yong

    Proceedings of NAMRI/SME, Vol. 39, 2011 Additive Manufacturing based on Optimized Mask Video@usc.edu, (213) 740-7829 ABSTRACT Additive manufacturing (AM) processes based on mask image projection and resolution of built components. KEYWORDS Additive manufacturing, Solid freeform fabrication, Mask image

  11. Sub-20-nm Alignment in Nanoimprint Lithography Using Moire Fringe

    E-Print Network [OSTI]

    , as expected, independent of the size of the gap between the wafer and the imprint mold. We achieved a single control or wafer-mold mismatch compensation. With better stages, precision temperature control, and wafer-mold is insufficient; one must achieve sub-30 nm overlay alignment accuracy in addition to low defect density and high

  12. Nanoscale GaAs metalsemiconductormetal photodetectors fabricated using nanoimprint lithography

    E-Print Network [OSTI]

    ­V) characteristics of the contacts are very sensi- tive to the surface states and defects. In this letter, we report mold with interdigited fin- gers was first created on a silicon substrate. Next, a layer of polymethylmethancrylate PMMA was spun on a semi- insulating SI GaAs substrate. Before imprinting, both the mold

  13. Defect mapping system

    DOE Patents [OSTI]

    Sopori, B.L.

    1995-04-11

    Apparatus for detecting and mapping defects in the surfaces of polycrystalline materials in a manner that distinguishes dislocation pits from grain boundaries includes a laser for illuminating a wide spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate rastor mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities. 20 figures.

  14. Four-mirror extreme ultraviolet (EUV) lithography projection system

    DOE Patents [OSTI]

    Cohen, Simon J (Pleasonton, CA); Jeong, Hwan J (Los Altos, CA); Shafer, David R (Fairfield, CT)

    2000-01-01

    The invention is directed to a four-mirror catoptric projection system for extreme ultraviolet (EUV) lithography to transfer a pattern from a reflective reticle to a wafer substrate. In order along the light path followed by light from the reticle to the wafer substrate, the system includes a dominantly hyperbolic convex mirror, a dominantly elliptical concave mirror, spherical convex mirror, and spherical concave mirror. The reticle and wafer substrate are positioned along the system's optical axis on opposite sides of the mirrors. The hyperbolic and elliptical mirrors are positioned on the same side of the system's optical axis as the reticle, and are relatively large in diameter as they are positioned on the high magnification side of the system. The hyperbolic and elliptical mirrors are relatively far off the optical axis and hence they have significant aspherical components in their curvatures. The convex spherical mirror is positioned on the optical axis, and has a substantially or perfectly spherical shape. The spherical concave mirror is positioned substantially on the opposite side of the optical axis from the hyperbolic and elliptical mirrors. Because it is positioned off-axis to a degree, the spherical concave mirror has some asphericity to counter aberrations. The spherical concave mirror forms a relatively large, uniform field on the wafer substrate. The mirrors can be tilted or decentered slightly to achieve further increase in the field size.

  15. Fundamentals of embossing nanoimprint lithography in polymer substrates.

    SciTech Connect (OSTI)

    Simmons, Blake Alexander; King, William P.

    2011-02-01

    The convergence of micro-/nano-electromechanical systems (MEMS/NEMS) and biomedical industries is creating a need for innovation and discovery around materials, particularly in miniaturized systems that use polymers as the primary substrate. Polymers are ubiquitous in the microelectronics industry and are used as sensing materials, lithography tools, replication molds, microfluidics, nanofluidics, and biomedical devices. This diverse set of operational requirements dictates that the materials employed must possess different properties in order to reduce the cost of production, decrease the scale of devices to the appropriate degree, and generate engineered devices with new functional properties at cost-competitive levels of production. Nanoscale control of polymer deformation at a massive scale would enable breakthroughs in all of the aforementioned applications, but is currently beyond the current capabilities of mass manufacturing. This project was focused on developing a fundamental understanding of how polymers behave under different loads and environments at the nanoscale in terms of performance and fidelity in order to fill the most critical gaps in our current knowledgebase on this topic.

  16. Lithography with MeV Energy Ions for Biomedical Applications: Accelerator Considerations

    SciTech Connect (OSTI)

    Sangyuenyongpipat, S.; Whitlow, H. J.; Nakagawa, S. T.; Yoshida, E.

    2009-03-10

    MeV ion beam lithographies are very powerful techniques for 3D direct writing in positive or negative photoresist materials. Nanometer-scale rough structures, or clear areas with straight vertical sidewalls as thin as a few 10's of nm in a resist of a few nm to 100 {mu}m thickness can be made. These capabilities are particularly useful for lithography in cellular- and sub-cellular level biomedical research and technology applications. It can be used for tailor making special structures such as optical waveguides, biosensors, DNA sorters, spotting plates, systems for DNA, protein and cell separation, special cell-growth substrates and microfluidic lab-on-a-chip devices. Furthermore MeV ion beam lithography can be used for rapid prototyping, and also making master stamps and moulds for mass production by hot embossing and nanoimprint lithography. The accelerator requirements for three different high energy ion beam lithography techniques are overviewed. We consider the special requirements placed on the accelerator and how this is achieved for a commercial proton beam writing tool.

  17. Comparison of infrared frequency selective surfaces fabricated by direct-write electron-beam and bilayer nanoimprint lithographies

    E-Print Network [OSTI]

    Krchnavek, Robert R.

    Comparison of infrared frequency selective surfaces fabricated by direct-write electron-beam-dipole resonant filters by direct-write electron-beam and nanoimprint lithographies. Such structures have been-write electron electron- beam lithography DEBL . Since DEBL is based on expo- sure of the resist point by point

  18. An optical parametric oscillator as a high-flux source of two-mode light for quantum lithography

    E-Print Network [OSTI]

    Dowling, Jonathan P.

    An optical parametric oscillator as a high-flux source of two-mode light for quantum lithography of contents for this issue, or go to the journal homepage for more Home Search Collections Journals About of Physics An optical parametric oscillator as a high-flux source of two-mode light for quantum lithography

  19. Using neutral metastable argon atoms and contamination lithography to form nanostructures in silicon, silicon dioxide, and gold

    E-Print Network [OSTI]

    Thywissen, Joseph

    Using neutral metastable argon atoms and contamination lithography to form nanostructures vapors present as dilute contaminants in the vacuum chamber, were used to create 80-nm features in Si, Si with similar contaminants present in a vacuum system to produce 8-nm features.1­3 This type of lithography

  20. Received 1 May 2013 | Accepted 26 Jul 2013 | Published 3 Sep 2013 Atomic layer lithography of wafer-scale

    E-Print Network [OSTI]

    Park, Namkyoo

    and high throughput. Here we introduce a new patterning technology based on atomic layer deposition lithography, combines atomic layer deposition (ALD) with `plug-and-peel' metal patterning using adhesive tapeARTICLE Received 1 May 2013 | Accepted 26 Jul 2013 | Published 3 Sep 2013 Atomic layer lithography

  1. 2496 IEEE PHOTONICS TECHNOLOGY LETTERS, VOL. 16, NO. 11, NOVEMBER 2004 Soft Lithography Replica Molding of Critically

    E-Print Network [OSTI]

    Huang, Yanyi

    Molding of Critically Coupled Polymer Microring Resonators Joyce K. S. Poon, Student Member, IEEE, Yanyi lithography replica molding to fabricate unclad polystyrene (PS) and clad SU-8 microring resonator filters of the microring resonator filters show the practicality of soft-lithography replica molding for the fabrication

  2. Soft X-ray Lithography Beamline at the Siam Photon Laboratory

    SciTech Connect (OSTI)

    Klysubun, P.; Chomnawang, N.; Songsiriritthigul, P.

    2007-01-19

    Construction of a soft x-ray lithography beamline utilizing synchrotron radiation generated by one of the bending magnets at the Siam Photon Laboratory is finished and the beamline is currently in a commissioning period. The beamline was modified from the existing monitoring beamline and is intended for soft x-ray lithographic processing and radiation biological research. The lithography exposure station with a compact one-dimensional scanning mechanism was constructed and assembled in-house. The front-end of the beamline has been modified to allow larger exposure area. The exposure station for studying radiation effects on biological samples will be set up in tandem with the lithography station, with a Mylar window for isolation. Several improvements to both the beamline and the exposure stations, such as improved scanning speed and the ability to adjust the exposure spectrum by means of low-Z filters, are planned and will be implemented in the near future.

  3. Fabrication of moth-eye structures on silicon by direct six-beam laser interference lithography

    SciTech Connect (OSTI)

    Xu, Jia; Zhang, Ziang; Weng, Zhankun; Wang, Zuobin Wang, Dapeng

    2014-05-28

    This paper presents a new method for the generation of cross-scale laser interference patterns and the fabrication of moth-eye structures on silicon. In the method, moth-eye structures were produced on a surface of silicon wafer using direct six-beam laser interference lithography to improve the antireflection performance of the material surface. The periodic dot arrays of the moth-eye structures were formed due to the ablation of the irradiance distribution of interference patterns on the wafer surface. The shape, size, and distribution of the moth-eye structures can be adjusted by controlling the wavelength, incidence angles, and exposure doses in a direct six-beam laser interference lithography setup. The theoretical and experimental results have shown that direct six-beam laser interference lithography can provide a way to fabricate cross-scale moth-eye structures for antireflection applications.

  4. Nanofabrication of Optical Elements for SXR and EUV Applications: Ion Beam Lithography as a New Approach

    SciTech Connect (OSTI)

    Lenz, J. [Institute for X-Optics, RheinAhrCampus Remagen, University of Applied Sciences Koblenz, Suedallee 2, 53424 Remagen (Germany); Research Group Electron Microscopy and Analytics, caesar Research Center, Ludwig-Erhard-Allee 2, 53175 Bonn (Germany); Krupp, N.; Irsen, S. [Research Group Electron Microscopy and Analytics, caesar Research Center, Ludwig-Erhard-Allee 2, 53175 Bonn (Germany); Wilhein, T. [Institute for X-Optics, RheinAhrCampus Remagen, University of Applied Sciences Koblenz, Suedallee 2, 53424 Remagen (Germany)

    2011-09-09

    Diffractive optical elements are important components for applications in soft x-ray and extreme ultraviolet radiation. At present, the standard fabrication method for such optics is based on electron beam lithography followed by nanostructuring. This requires a series of complex processes including exposure, reactive ion-etching, and electro-plating. We report on experiments showing the single-step fabrication of such elements using ion beam lithography. Both transmission and reflection gratings were fabricated and successfully implemented as spectrometers at laboratory soft x-ray sources. Additionally, first steps toward zone plate fabrication are described.

  5. Critical dimension and pattern size enhancement using pre-strained lithography

    SciTech Connect (OSTI)

    Hong, Jian-Wei [Department of Power Mechanical Engineering, National Tsing Hua University, 101, Section 2, Kuang Fu Road, Hsin Chu 30013, Taiwan (China); Yang, Chung-Yuan [Institute of NanoEngineering and MicroSystems, National Tsing Hua University, 101, Section 2, Kuang Fu Road, Hsin Chu 30013, Taiwan (China); Lo, Cheng-Yao, E-mail: chengyao@mx.nthu.edu.tw [Department of Power Mechanical Engineering, National Tsing Hua University, 101, Section 2, Kuang Fu Road, Hsin Chu 30013, Taiwan (China); Institute of NanoEngineering and MicroSystems, National Tsing Hua University, 101, Section 2, Kuang Fu Road, Hsin Chu 30013, Taiwan (China)

    2014-10-13

    This paper proposes a non-wavelength-shortening-related critical dimension and pattern size reduction solution for the integrated circuit industry that entails generating strain on the substrate prior to lithography. Pattern size reduction of up to 49% was achieved regardless of shape, location, and size on the xy plane, and complete theoretical calculations and process steps are described in this paper. This technique can be applied to enhance pattern resolution by employing materials and process parameters already in use and, thus, to enhance the capability of outdated lithography facilities, enabling them to particularly support the manufacturing of flexible electronic devices with polymer substrates.

  6. Shedding Light on Nanocrystal Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Shedding Light on Nanocrystal Defects Print Nanocrystals have been the focus of much scientific interest lately, given their various advantageous mechanical properties. Their...

  7. Selectively patterning polymer opal films via microimprint lithography

    E-Print Network [OSTI]

    Ding, Tao; Zhao, Qibin; Smoukov, Stoyan; Baumberg, Jeremy J.

    2014-09-01

    PDMS mold with epoxy resin. The initial stamp used com- prises of a hexagonal array of 30 µm high posts with diameter 100 µm and intervening gap of 50 µm (see SI Figure S1). The standard imprinting process used 30 bar pressure at 110 °C for 150 s... because of a decrease of lattice spacing on compression and an increase of lattice spacing on sideways extrusion. The peak refl ectivities drop to ?30%, which may arise because of non-homogeneous fl ows or the introduc- tion of defects during squeezing...

  8. Sub-5 keV electron-beam lithography in hydrogen silsesquioxane resist

    E-Print Network [OSTI]

    Manfrinato, Vitor R.

    We fabricated 9–30 nm half-pitch nested Ls and 13–15 nm half-pitch dot arrays, using 2 keV electron-beam lithography with hydrogen silsesquioxane (HSQ) as the resist. All structures with 15 nm half-pitch and above were ...

  9. Pattern transfer of electron beam modified self-assembled monolayers for high-resolution lithography

    E-Print Network [OSTI]

    Parikh, Atul N.

    Pattern transfer of electron beam modified self-assembled monolayers for high-resolution electron beam lithography. Focused electron beams from 1 to 50 keV and scanning tunneling microscopy at 10 of electron beam damage on the monolayers and the subsequent etching reactions has been explored through x

  10. Microchannel molding: A soft lithography-inspired approach to micrometer-scale patterning

    E-Print Network [OSTI]

    Aksay, Ilhan A.

    Microchannel molding: A soft lithography-inspired approach to micrometer-scale patterning large amounts of shrinkage during drying, topographical distortions develop. In place of patterning the elastomeric mold, the network of capillary channels was patterned directly into the substrate surface

  11. IEEE TRANSACTIONS ON NANOTECHNOLOGY, VOL. 5, NO. 1, JANUARY 2006 3 Nanopatterning With Interferometric Lithography

    E-Print Network [OSTI]

    Rocca, Jorge J.

    IEEE TRANSACTIONS ON NANOTECHNOLOGY, VOL. 5, NO. 1, JANUARY 2006 3 Nanopatterning the potential of compact EUV lasers in nanotechnology applications. Index Terms--Nanotechnology, photolithography, X-ray lasers, X-ray lithography. THE increasing activity in nanotechnology and nanoscience fuels

  12. INTEGRATED SIMULATION OF DISCHARGE AND LASER PRODUCED PLASMAS IN EUV LITHOGRAPHY DEVICES

    E-Print Network [OSTI]

    Harilal, S. S.

    of the plasma energy that includes thermal energy of electron and ionization energy; ie - ion component to support the throughput requirements of High-Volume Manufacturing lithography exposure tools. One method not only of power sources but also plasma irradiation parameters, plasma energy deposition, target material

  13. Low-voltage spatial-phase-locked scanning-electron-beam lithography

    E-Print Network [OSTI]

    Cheong, Lin Lee

    2010-01-01

    Spatial-phase-locked electron-beam lithography (SPLEBL) is a method that tracks and corrects the position of an electron-beam in real-time by using a reference grid placed above the electron-beam resist. In this thesis, ...

  14. Silicon nanopillar anodes for lithium-ion batteries using nanoimprint lithography with flexible molds

    E-Print Network [OSTI]

    Arnold, Craig B.

    ) The lithium ion battery, a preferred energy storage technology, is limited by its volumetric and gravimetric. INTRODUCTION The lithium ion battery has become the energy storage me- dium of choice for almost allSilicon nanopillar anodes for lithium-ion batteries using nanoimprint lithography with flexible

  15. Optimization Criteria for SRAM Design -Lithography Contribution Daniel C. Cole,b

    E-Print Network [OSTI]

    Cole, Dan C.

    Optimization Criteria for SRAM Design - Lithography Contribution Daniel C. Cole,b Orest Bula, to predict and "optimize" the printed shapes through all critical levels in a dense SRAM design. Our key emphasis here is on "optimization criteria," namely, having achieved good predictability for printability

  16. Heidelberg DWL66 Direct Write Lithography System Biomolecular Nanotechnology Center, UC Berkeley

    E-Print Network [OSTI]

    Healy, Kevin Edward

    Heidelberg DWL66 Direct Write Lithography System Biomolecular Nanotechnology Center, UC Berkeley Standard Operating Procedure Prepared By: Frankie Myers (fbm@berkeley.edu) Updated: July 30, 2010, Peter Ledochowitz) may use this machine. Qualification must include one supervised run. SAFETY WARNING

  17. Sub-10 nm imprint lithography and applications Stephen Y. Chou,a)

    E-Print Network [OSTI]

    imprint. Moreover, imprint lithography was used to fabricate the silicon quantum dot, wire, and ring to the ultrasmall force in tapping mode, both the nano-CD and the scanning probe will not show noticeable wear after-cost nanopatterning technology, particularly a nanolithography which allows complete free- dom in designing the size

  18. Flexible CO2 laser system for fundamental research related to an extreme ultraviolet lithography source

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    Flexible CO2 laser system for fundamental research related to an extreme ultraviolet lithography 2009; published online 10 December 2009 A CO2 laser system with flexible parameters was developed 1010 W/cm2 . Utilizing this CO2 MOPA laser system, high conversion efficiency from laser to in-band 2

  19. A novel lithography technique for formation of large areas of uniform nanostructures

    E-Print Network [OSTI]

    Shahriar, Selim

    such as plasmonics, sensors, storage devices, solar cells, nano-filtration and artificial kidneys require applications such as surface plasmonics[1] , data storage[2] , optoelectronic devices[3] , and nanoA novel lithography technique for formation of large areas of uniform nanostructures Wei Wu

  20. Room-temperature Si single-electron memory fabricated by nanoimprint lithography

    E-Print Network [OSTI]

    , Haixiong Ge, Christopher Keimel, and Stephen Y. Chou NanoStructure Laboratory, Department of Electrical using nanoimprint lithography NIL . The devices consist of a narrow channel metal­ oxide­semiconductor field-effect transistor and a sub-10-nm storage dot, which is located between the channel and the gate

  1. Holographic Chern-Simons Defects

    E-Print Network [OSTI]

    Fujita, Mitsutoshi; Meyer, Rene; Sugimoto, Shigeki

    2016-01-01

    We study SU(N) Yang-Mills-Chern-Simons theory in the presence of defects that shift the Chern-Simons level from a holographic point of view by embedding the system in string theory. The model is a D3-D7 system in Type IIB string theory, whose gravity dual is given by the AdS soliton background with probe D7-branes attaching to the AdS boundary along the defects. We holographically renormalize the free energy of the defect system with sources, from which we obtain the correlation functions for certain operators naturally associated to these defects. We find interesting phase transitions when the separation of the defects as well as the temperature are varied. We also discuss some implications for the Fractional Quantum Hall Effect and for two-dimensional QCD.

  2. Methane Digesters and Biogas Recovery - Masking the Environmental Consequences of Industrial Concentrated Livestock Production

    E-Print Network [OSTI]

    Di Camillo, Nicole G.

    2011-01-01

    Methane Digesters and Biogas Recovery-Masking theII. METHANE DIGESTERS AND BIOGAs RECOVERY- IN THE2011] METHANE DIGESTERS AND BIOGAS RECOVERY methane, and 64%

  3. Methane Digesters and Biogas Recovery - Masking the Environmental Consequences of Industrial Concentrated Livestock Production

    E-Print Network [OSTI]

    Di Camillo, Nicole G.

    2011-01-01

    Methane Digesters and Biogas Recovery-Masking theII. METHANE DIGESTERS AND BIOGAs RECOVERY- IN THEEVEN BEYOND MANURE-ASSOCIATED METHANE EMISSIONS, INDUSTRIAL

  4. Analysis of Optics and Mask Contamination in SEMATECH EUV Micro-Exposure Tools

    E-Print Network [OSTI]

    Wuest, Andrea

    2008-01-01

    of Optics and Mask Contamination in SEMATECH EUV MioroTools IEUVI Optics Contamination/Lifetime TWG Sapporo,of spot inside visible contamination. sputter time (min) c

  5. Carbon contamination of extreme ultraviolet (EUV) mask and its effect on imaging

    E-Print Network [OSTI]

    Fan, Yu-Jen

    2009-01-01

    induced carbon contamination of extreme ultraviolet optics."potential LWR due to the contamination topography may be anet aI. , "Accelerated contamination testing of EUV masks."

  6. A masking analysis of glass pattern perception Department of Psychology, National Taiwan University,

    E-Print Network [OSTI]

    Chen, Chein Chung

    A masking analysis of glass pattern perception Department of Psychology, National Taiwan University, Taipei, Taiwan, & Neurobiology and Cognitive Science Center, National Taiwan University, Taipei, Taiwan

  7. 2010 Defects in Semiconductors GRC

    SciTech Connect (OSTI)

    Shengbai Zhang

    2011-01-06

    Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, as well as an emphasis on the development of novel defect detection methods and first-principles defect theories. Electronic, magnetic, and optical properties of bulk, thin film, and nanoscale semiconductors will be discussed in detail. In contrast to many conferences, which tend to focus on specific semiconductors, this conference will deal with point and extended defects in a broad range of electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, oxides, sp{sup 2} carbon based-materials, and photovoltaic/solar cell materials, and in understanding important defect phenomena such as doping bottleneck in nanostructures and the diffusion of defects and impurities. The program consists of about twenty invited talks and a number of contributed poster sessions. The emphasis should be on work which has yet to be published. The large amount of discussion time provides an ideal forum for dealing with topics that are new and/or controversial.

  8. Self healing of defected graphene

    SciTech Connect (OSTI)

    Chen, Jianhui; Shi, Tuwan; Cai, Tuocheng; Wu, Xiaosong; Yu, Dapeng [School of Physics, Peking University, Beijing 100871 (China) [School of Physics, Peking University, Beijing 100871 (China); State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871 (China); Xu, Tao; Sun, Litao [SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Southeast University, Nanjing 210096 (China)] [SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Southeast University, Nanjing 210096 (China)

    2013-03-11

    For electronics applications, defects in graphene are usually undesirable because of their ability to scatter charge carriers, thereby reduce the carrier mobility. It would be extremely useful if the damage can be repaired. In this work, we employ Raman spectroscopy, X-ray photoemission spectroscopy, transmission electron microscopy, and electrical measurements to study defects in graphene introduced by argon plasma bombardment. We have found that majority of these defects can be cured by a simple thermal annealing process. The self-healing is attributed to recombination of mobile carbon adatoms with vacancies. With increasing level of plasma induced damage, the self-healing becomes less effective.

  9. Design and analysis of a scanning beam interference lithography system for patterning gratings with nanometer-level distortions

    E-Print Network [OSTI]

    Konkola, Paul Thomas, 1973-

    2003-01-01

    This thesis describes the design and analysis of a system for patterning large-area gratings with nanometer level phase distortions. The novel patterning method, termed scanning beam interference lithography (SBIL), uses ...

  10. Sub-10-nm half-pitch electron-beam lithography by using poly(methyl methacrylate) as a negative resist

    E-Print Network [OSTI]

    Berggren, Karl K.

    Developing high-resolution resists and processes for electron-beam lithography is of great importance for high-density magnetic storage, integrated circuits, and nanoelectronic and nanophotonic devices. Until now, hydrogen ...

  11. Graphene Edge Lithography Guibai Xie, Zhiwen Shi, Rong Yang, Donghua Liu, Wei Yang, Meng Cheng, Duoming Wang, Dongxia Shi,

    E-Print Network [OSTI]

    Zhang, Guangyu

    Graphene Edge Lithography Guibai Xie, Zhiwen Shi, Rong Yang, Donghua Liu, Wei Yang, Meng Cheng: Fabrication of graphene nanostructures is of importance for both investigating their intrinsic physical approach for graphene nanostructures. Compared with conventional lithographic fabrication techniques

  12. Sequential detection of web defects

    DOE Patents [OSTI]

    Eichel, Paul H. (Albuquerque, NM); Sleefe, Gerard E. (Cedar Crest, NM); Stalker, K. Terry (Albuquerque, NM); Yee, Amy A. (Albuquerque, NM)

    2001-01-01

    A system for detecting defects on a moving web having a sequential series of identical frames uses an imaging device to form a real-time camera image of a frame and a comparitor to comparing elements of the camera image with corresponding elements of an image of an exemplar frame. The comparitor provides an acceptable indication if the pair of elements are determined to be statistically identical; and a defective indication if the pair of elements are determined to be statistically not identical. If the pair of elements is neither acceptable nor defective, the comparitor recursively compares the element of said exemplar frame with corresponding elements of other frames on said web until one of the acceptable or defective indications occur.

  13. Inference for the dependent competing risks model with masked causes of failure

    E-Print Network [OSTI]

    Craiu, V. Radu

    Inference for the dependent competing risks model with masked causes of failure Radu V. Craiu Æ/fail for different reasons. The cause specific hazard rates are taken to be piecewise constant functions. A complication arises when some of the failures are masked within a group of possible causes. Traditionally

  14. Inference based on the em algorithm for the competing risk model with masked causes of failure

    E-Print Network [OSTI]

    Duchesne, Thierry

    Inference based on the em algorithm for the competing risk model with masked causes of failure parameterised competing risks model with masked causes of failure and second-stage data. With a carefully chosen definition of complete data, the maximum likelihood estimation of the cause-specific hazard functions

  15. An Efficient Shift Invariant Rasterization Algorithm for All-Angle Mask Patterns in ILT

    E-Print Network [OSTI]

    Chu, Chris C.-N.

    rasterize the ILT masks before they are inputted to the simulation tools. Currently, there is no high project- ing COG (Chrome on Glass) circuit masks onto coated silicon Permission to make digital or hard dis- torts the shapes on reticle, as the imaging process cuts off all the high-frequency content

  16. ATOMIC FORCE LITHOGRAPHY OF NANO/MICROFLUIDIC CHANNELS FOR VERIFICATION AND MONITORING OF AQUEOUS SOLUTIONS

    SciTech Connect (OSTI)

    Mendez-Torres, A.; Torres, R.; Lam, P.

    2011-07-15

    The growing interest in the physics of fluidic flow in nanoscale channels, as well as the possibility for high sensitive detection of ions and single molecules is driving the development of nanofluidic channels. The enrichment of charged analytes due to electric field-controlled flow and surface charge/dipole interactions along the channel can lead to enhancement of sensitivity and limits-of-detection in sensor instruments. Nuclear material processing, waste remediation, and nuclear non-proliferation applications can greatly benefit from this capability. Atomic force microscopy (AFM) provides a low-cost alternative for the machining of disposable nanochannels. The small AFM tip diameter (< 10 nm) can provide for features at scales restricted in conventional optical and electron-beam lithography. This work presents preliminary results on the fabrication of nano/microfluidic channels on polymer films deposited on quartz substrates by AFM lithography.

  17. ATOMIC FORCE LITHOGRAPHY OF NANO MICROFLUIDIC CHANNELS FOR VERIFICATION AND MONITORING IN AQUEOUS SOLUTIONS

    SciTech Connect (OSTI)

    Torres, R.; Mendez-Torres, A.; Lam, P.

    2011-06-09

    The growing interest in the physics of fluidic flow in nanoscale channels, as well as the possibility for high sensitive detection of ions and single molecules is driving the development of nanofluidic channels. The enrichment of charged analytes due to electric field-controlled flow and surface charge/dipole interactions along the channel can lead to enhancement of sensitivity and limits-of-detection in sensor instruments. Nuclear material processing, waste remediation, and nuclear non-proliferation applications can greatly benefit from this capability. Atomic force microscopy (AFM) provides a low-cost alternative for the machining of disposable nanochannels. The small AFM tip diameter (< 10 nm) can provide for features at scales restricted in conventional optical and electron-beam lithography. This work presents preliminary results on the fabrication of nano/microfluidic channels on polymer films deposited on quartz substrates by AFM lithography.

  18. Replication of photonic crystals by soft ultraviolet-nanoimprint lithography Michele Belotti, Jrmi Torres,a

    E-Print Network [OSTI]

    photopolymerization through a soft elastomer-based mold is applied to the fabrication of silicon-on-insulator slab of linear defects in the periodicity. Guiding occurs along the defect line, i.e., a missing row of holes forming the so-called W1 defect.5 In order to enhance this behavior, high dielectric contrast between core

  19. Mask effects on cosmological studies with weak-lensing peak statistics

    SciTech Connect (OSTI)

    Liu, Xiangkun; Pan, Chuzhong; Fan, Zuhui; Wang, Qiao

    2014-03-20

    With numerical simulations, we analyze in detail how the bad data removal, i.e., the mask effect, can influence the peak statistics of the weak-lensing convergence field reconstructed from the shear measurement of background galaxies. It is found that high peak fractions are systematically enhanced because of the presence of masks; the larger the masked area is, the higher the enhancement is. In the case where the total masked area is about 13% of the survey area, the fraction of peaks with signal-to-noise ratio ? ? 3 is ?11% of the total number of peaks, compared with ?7% of the mask-free case in our considered cosmological model. This can have significant effects on cosmological studies with weak-lensing convergence peak statistics, inducing a large bias in the parameter constraints if the effects are not taken into account properly. Even for a survey area of 9 deg{sup 2}, the bias in (? {sub m}, ?{sub 8}) is already intolerably large and close to 3?. It is noted that most of the affected peaks are close to the masked regions. Therefore, excluding peaks in those regions in the peak statistics can reduce the bias effect but at the expense of losing usable survey areas. Further investigations find that the enhancement of the number of high peaks around the masked regions can be largely attributed to the smaller number of galaxies usable in the weak-lensing convergence reconstruction, leading to higher noise than that of the areas away from the masks. We thus develop a model in which we exclude only those very large masks with radius larger than 3' but keep all the other masked regions in peak counting statistics. For the remaining part, we treat the areas close to and away from the masked regions separately with different noise levels. It is shown that this two-noise-level model can account for the mask effect on peak statistics very well, and the bias in cosmological parameters is significantly reduced if this model is applied in the parameter fitting.

  20. An investigation of defect detection using random defect excitation and deterministic defect observation in complex integrated logic circuits 

    E-Print Network [OSTI]

    Dworak, Jennifer

    2013-02-22

    aWhenever integrated circuits are manufactured, a certain percentage of those circuits will be defective. Defective circuits present problems for both the manufacturers who wish to maintain a good reputation with their customers and the consumers...

  1. MESOSCALE DESCRIPTION OF DEFECTED MATERIALS

    E-Print Network [OSTI]

    Vinals, Jorge

    MESOSCALE DESCRIPTION OF DEFECTED MATERIALS Jorge Vi~nals School of Physics and Astronomy. Laughlin) Small but finite wavenumber and finite frequency ("mesoscale") response functions and transport;MESOSCALE DESCRIPTION B B B B B B B A B A B A A B B A A A A BB A B Microscopic Mesoscopic Macroscopic vn

  2. Defects in Crystals Faizan Nazar

    E-Print Network [OSTI]

    Sengun, Mehmet Haluk

    that are close to the defect. Figure : A 2D sketch of a perfect lattice and a lattice which has been re researchers are also into looking into new materials like graphene), but manufacturers also introduce. The new material is called a semiconductor. There are two types of doping, called p-type and n-type, short

  3. Data Collection for the MASK Kiosk: WOz vs Prototype System A. Life, I. Saltery

    E-Print Network [OSTI]

    Data Collection for the MASK Kiosk: WOz vs Prototype System A. Life, I. Saltery Ergonomics Unit state-of-the-art speech technology. In this paperwe report on our efforts aimed at evaluating

  4. Ice-assisted electron beam lithography of graphene This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Ice-assisted electron beam lithography of graphene This article has been downloaded from IOPscience-assisted electron beam lithography of graphene Jules A Gardener1 and J A Golovchenko1,2 1 Department of Physics demonstrate that a low energy focused electron beam can locally pattern graphene coated with a thin ice layer

  5. Integrated circuit mask generation using a raster scanned laser trimming system 

    E-Print Network [OSTI]

    Gourley, Kevin Dwayne

    1982-01-01

    and developed . for the production of integrated circuit master reticles. The novelty of this approach is the use of a commercial Nd:YAG laser trimming system as a raster scanning laser reticle generator. A previous method employing an ESI Model 44 Laser... Integrated Circuit Mask Making), supports designs of even very large scale integration (VLSI) complexities. Low cost and high versatility makes the use of a commercial laser trimmer as a mask gener ation system very attractive for research applications...

  6. Tracking Defect Warnings Across Versions Jaime Spacco

    E-Print Network [OSTI]

    Hovemeyer, David H.

    the results of tracking defect warnings across Sun's Java runtime library. Categories and Subject DescriptorsTracking Defect Warnings Across Versions Jaime Spacco£ , David HovemeyerÝ , William Pugh£ £ Dept of reasons, it is important to be able to track the occurrence of each potential defect over multiple

  7. Facile electron-beam lithography technique for irregular and fragile substrates

    SciTech Connect (OSTI)

    Chang, Jiyoung; Zhou, Qin; Zettl, Alex, E-mail: azettl@berkeley.edu [Department of Physics, University of California at Berkeley, Berkeley, California 94720 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Kavli Energy NanoSciences Institute at the University of California, Berkeley, California 94720 (United States)

    2014-10-27

    A facile technique is presented which enables high-resolution electron beam lithography on irregularly-shaped, non-planar or fragile substrates such as the edges of a silicon chip, thin and narrow suspended beams and bridges, or small cylindrical wires. The method involves a spin-free dry-transfer of pre-formed uniform-thickness polymethyl methacrylate, followed by conventional electron beam writing, metal deposition, and lift-off. High-resolution patterning is demonstrated for challenging target substrates. The technique should find broad application in micro- and nano-technology research arenas.

  8. Wafer chamber having a gas curtain for extreme-UV lithography

    DOE Patents [OSTI]

    Kanouff, Michael P. (Livermore, CA); Ray-Chaudhuri, Avijit K. (Livermore, CA)

    2001-01-01

    An EUVL device includes a wafer chamber that is separated from the upstream optics by a barrier having an aperture that is permeable to the inert gas. Maintaining an inert gas curtain in the proximity of a wafer positioned in a chamber of an extreme ultraviolet lithography device can effectively prevent contaminants from reaching the optics in an extreme ultraviolet photolithography device even though solid window filters are not employed between the source of reflected radiation, e.g., the camera, and the wafer. The inert gas removes the contaminants by entrainment.

  9. Optics near an hyperbolic defect

    E-Print Network [OSTI]

    Fumeron, Sébastien; Santos, Fernando; Pereira, Erms; Moraes, Fernando

    2015-01-01

    We examine the properties of a new family of defects called hyperbolic disclinations, and discuss their possible use for the design of perfect optical absorbers. In hyperbolic metamaterials, the ratio of ordinary and extraordinary permittivities is negative, which leads to an effective metric of Kleinian signature (two timelike coordinates). Considering a disclination in the hyperbolic nematic host matrix, we show that the timelike geodesics are Poinsot spirals, i.e. whatever the impact parameter of an incident light beam, it is confined and whirls about the defect core. The trapping effect does not require light to be coherent. This property also remains in the wave formalism, which may be the sign for many potential applications.

  10. Effects of Stone-Wales and vacancy defects in atomic-scale friction on defective graphite

    SciTech Connect (OSTI)

    Sun, Xiao-Yu; Wu, RunNi; Xia, Re; Chu, Xi-Hua; Xu, Yuan-Jie

    2014-05-05

    Graphite is an excellent solid lubricant for surface coating, but its performance is significantly weakened by the vacancy or Stone-Wales (SW) defect. This study uses molecular dynamics simulations to explore the frictional behavior of a diamond tip sliding over a graphite which contains a single defect or stacked defects. Our results suggest that the friction on defective graphite shows a strong dependence on defect location and type. The 5-7-7-5 structure of SW defect results in an effectively negative slope of friction. For defective graphite containing a defect in the surface, adding a single vacancy in the interior layer will decrease the friction coefficients, while setting a SW defect in the interior layer may increase the friction coefficients. Our obtained results may provide useful information for understanding the atomic-scale friction properties of defective graphite.

  11. Ultra-lightweight nanorelief networks : photopatterned microframes

    E-Print Network [OSTI]

    Choi, Taeyi

    2007-01-01

    Lightweight nano-network structures in polymers have been fabricated and investigated for their mechanical properties. Fabrication techniques via holographic interference lithography and phase mask lithography were implemented ...

  12. The SEMATECH Berkeley MET & DCT: a quest for 14-nm half-pitch in chemically amplified resist, OOB contrast of EUV resists, and 6.x-nm lithography

    E-Print Network [OSTI]

    McClinton, Brittany

    2013-01-01

    phase-shift-mask (pseudo-PSM) imaging, providing earlypitch, using the pseudo-PSM technique. In September 2011,

  13. Conformal nets III: fusion of defects

    E-Print Network [OSTI]

    Arthur Bartels; Christopher L. Douglas; André Henriques

    2015-02-21

    Conformal nets provides a mathematical model for conformal field theory. We define a notion of defect between conformal nets, formalizing the idea of an interaction between two conformal field theories. We introduce an operation of fusion of defects, and prove that the fusion of two defects is again a defect, provided the fusion occurs over a conformal net of finite index. There is a notion of sector (or bimodule) between two defects, and operations of horizontal and vertical fusion of such sectors. Our most difficult technical result is that the horizontal fusion of the vacuum sectors of two defects is isomorphic to the vacuum sector of the fused defect. Equipped with this isomorphism, we construct the basic interchange isomorphism between the horizontal fusion of two vertical fusions and the vertical fusion of two horizontal fusions of sectors.

  14. Soft holographic interference lithography microlens for enhanced organic light emitting diode light extraction

    SciTech Connect (OSTI)

    Park, Joong-Mok; Gan, Zhengqing; Leung, Wai Y.; Liu, Rui; Ye, Zhuo; Constant, Kristen; Shinar, Joseph; Shinar, Ruth; Ho, Kai-Ming

    2011-06-06

    Very uniform 2 {micro}m-pitch square microlens arrays ({micro}LAs), embossed on the blank glass side of an indium-tin-oxide (ITO)-coated 1.1 mm-thick glass, are used to enhance light extraction from organic light-emitting diodes (OLEDs) by {approx}100%, significantly higher than enhancements reported previously. The array design and size relative to the OLED pixel size appear to be responsible for this enhancement. The arrays are fabricated by very economical soft lithography imprinting of a polydimethylsiloxane (PDMS) mold (itself obtained from a Ni master stamp that is generated from holographic interference lithography of a photoresist) on a UV-curable polyurethane drop placed on the glass. Green and blue OLEDs are then fabricated on the ITO to complete the device. When the {mu}LA is {approx}15 x 15 mm{sup 2}, i.e., much larger than the {approx}3 x 3 mm{sup 2} OLED pixel, the electroluminescence (EL) in the forward direction is enhanced by {approx}100%. Similarly, a 19 x 25 mm{sup 2} {mu}LA enhances the EL extracted from a 3 x 3 array of 2 x 2 mm{sup 2} OLED pixels by 96%. Simulations that include the effects of absorption in the organic and ITO layers are in accordance with the experimental results and indicate that a thinner 0.7 mm thick glass would yield a {approx}140% enhancement.

  15. 3D microfabrication of single-wall carbon nanotube/polymer composites by two-photon polymerization lithography

    E-Print Network [OSTI]

    Natelson, Douglas

    3D microfabrication of single-wall carbon nanotube/polymer composites by two-photon polymerization online 16 March 2013 A B S T R A C T We present a method to develop single-wall carbon nanotube (SWCNT)/polymer-photon polymerization lithography, allows one to fabricate three-dimensional SWCNT/polymer composites with a minimum

  16. Polymer sphere lithography for solid oxide fuel cells: a route to functional, well-defined electrode structures

    E-Print Network [OSTI]

    Polymer sphere lithography for solid oxide fuel cells: a route to functional, well. Introduction Dramatic breakthroughs in the materials, particularly electrode materials, for solid oxide fuel cells (SOFCs) have been reported in recent years.1­3 Fundamental understanding of the electro- catalytic

  17. Contact lens wear with the USAF protective integrated hood/mask chemical defense ensemble

    SciTech Connect (OSTI)

    Dennis, R.J.; Miller, R.E. II; Peterson, R.D.; Jackson, W.G. Jr. (USAF, Armstrong Laboratory, Brooks AFB, TX (United States))

    1992-07-01

    The Protective Integrated Hood/Mask (PIHM) chemical defense aircrew ensemble blows air from the mask's plenum across the visor at a rate of approximately 15 L/min in order to prevent fogging of the visor and to cool the aircrew member's face. This study was designed to determine the effect of the PIHM airflow on soft contact lens (SCL) dehydration, contact lens comfort, and corneal integrity. There were 26 subjects who participated in this study: 15 SCL wearers, six rigid gas-permeable (RGP) wearers, and five nonspectacle wearing controls. Contrast acuity with the three Regan charts, subjective comfort, and relative humidity (RH) and temperature readings under the PIHM mask were monitored every 0.5 h during 6-h laboratory rides. Slit-lamp examinations and SCL water content measurements with a hand-held Abbe refractometer were made before and after the rides. High RH under the mask may have accounted for the moderate SCL dehydration (8.3 percent), no decrease in contrast acuity for any group, and lack of corneal stress. Although all groups experienced some inferior, epithelial, punctate keratopathy, RGP wearers had the most significant effects. SCLs performed relatively well in the PIHM mask environment. Testing with other parameter designs is necessary before recommending RGPs with the PIHM system. 19 refs.

  18. Use of a hard mask for formation of gate and dielectric via nanofilament field emission devices

    DOE Patents [OSTI]

    Morse, Jeffrey D. (Martinez, CA); Contolini, Robert J. (Lake Oswego, OR)

    2001-01-01

    A process for fabricating a nanofilament field emission device in which a via in a dielectric layer is self-aligned to gate metal via structure located on top of the dielectric layer. By the use of a hard mask layer located on top of the gate metal layer, inert to the etch chemistry for the gate metal layer, and in which a via is formed by the pattern from etched nuclear tracks in a trackable material, a via is formed by the hard mask will eliminate any erosion of the gate metal layer during the dielectric via etch. Also, the hard mask layer will protect the gate metal layer while the gate structure is etched back from the edge of the dielectric via, if such is desired. This method provides more tolerance for the electroplating of a nanofilament in the dielectric via and sharpening of the nanofilament.

  19. Dry Lithography of Large-Area, Thin-Film Organic Semiconductors Using Frozen CO[subscript 2] Resists

    E-Print Network [OSTI]

    Mendoza, Hiroshi A.

    To address the incompatibility of organic semiconductors with traditional photolithography, an inert, frozen CO[subscript 2] resist is demonstrated that forms an in situ shadow mask. Contact with a room-temperature ...

  20. Fabrication of 60-nm transistors on 4-in. wafer using nanoimprint at all lithography levels

    E-Print Network [OSTI]

    the needed overlay accuracy in multilayer NIL, large-area uniformity, and low defect density. Here, we by a mechanical deformation of the resist shape using a mold. During the deformation, a nanoimprint resist made

  1. Progress in the fabrication of high aspect ratio zone plates by soft x-ray lithography.

    SciTech Connect (OSTI)

    Divan, R.; Mancini, D. C.; Moldovan, N. A.; Lai, B.; Assoufid, L.; Leondard, Q.; Cerrina, F.

    2002-08-13

    Soft x-ray lithography technology has been applied to fabrication of phase shifting Fresnel Zone Plate (FZP's) for hard x-rays. Effects of the exposure conditions, developing system, and electroplating process parameters on line width and aspect ratio have been analyzed. The process has been optimized and an aspect ratio of 11 has been achieved for 110 nm outermost zone width. SEM and AFM have been used for preliminary metrology of the FZPs. The FZP optical performance was characterized at 8 keV photon energy at the 2-ID-D beam line at the Advanced Photon Source. Focusing efficiencies of 23% for FZPs apertures to 100 microns and 18% for 150-micron-diameter apertures have been obtained. The parameters of the fabricated FZP are in good agreement with the predicted values.

  2. Study of nano imprinting using soft lithography on Krafty glue and PVDF polymer thin films

    SciTech Connect (OSTI)

    Sankar, M. S. Ravi, E-mail: rameshg.phy@pondiuni.edu; Gangineni, Ramesh Babu, E-mail: rameshg.phy@pondiuni.edu [Department of Physics, Pondicherry University, R. V. Nagar, Kalapet, Puducherry - 605014 (India)

    2014-04-24

    The present work reveals soft lithography strategy based on self assembly and replica molding for carrying out micro and nanofabrication. It provides a convenient, effective and very low cost method for the formation and manufacturing of micro and nano structures. Al-layer of compact disc (sony CD-R) used as a stamp with patterned relief structures to generate patterns and structures with pattern size of 100nm height, 1.7 ?m wide. In literature, PDMS (Polydimethylsiloxane) solution is widely used to get negative copy of the Al-layer. In this work, we have used inexpensive white glue (Polyvinylacetate + water), 15gm (?5) and PVDF (Polyvinylidene difluoride) spin coated films and successfully transferred the nano patterns of Al layer on to white glue and PVDF films.

  3. A HIGH ASPECT RATIO, FLEXIBLE, TRANSPARENT AND LOW-COST PARYLENE-C SHADOW MASK TECHNOLOGY FOR MICROPATTERNING APPLICATIONS

    E-Print Network [OSTI]

    Dokmeci, Mehmet

    A HIGH ASPECT RATIO, FLEXIBLE, TRANSPARENT AND LOW-COST PARYLENE-C SHADOW MASK TECHNOLOGY and Technology, MIT, Cambridge, MA, USA Abstract: In this paper, we present a flexible parylene-C shadow mask technology for creating microscale patterns on flat and curved surfaces. The smallest feature size of 4 µm

  4. USER EVALUATION OF THE MASK KIOSK L. Lamel, S. Bennacef, J.L. Gauvain, H. Dartiguesy, J.N. Tememy

    E-Print Network [OSTI]

    USER EVALUATION OF THE MASK KIOSK L. Lamel, S. Bennacef, J.L. Gauvain, H. Dartiguesy, J.N. Tememy) and the Ergonomics group at UCL. The time to complete the transaction with the MASK kiosk is reduced by about 30-CNRS, the SNCF (the French Railways) and the Ergonomics group at UCL (Univeristy College London). The physical

  5. A direct-write thick-film lithography process for multi-parameter control of tooling in continuous roll-to-roll microcontact printing

    E-Print Network [OSTI]

    Nietner, Larissa F

    2014-01-01

    Roll-to-roll (R2R) microcontact printing ([mu]CP) aims to transform micron-precision soft lithography in a continuous, large-scale, high-throughput process for large-area surface patterning, flexible electronics and ...

  6. The application of nanosecond-pulsed laser welding technology in MEMS packaging with a shadow mask$

    E-Print Network [OSTI]

    Lin, Liwei

    The application of nanosecond-pulsed laser welding technology in MEMS packaging with a shadow mask wiring is not pre- ferred. A comprehensive review on laser welding was given in [6]. The laser welding of laser welding is to create the liquid pool by absorption of incident radiation, allow it to grow

  7. New MS-Windows-Based Educational Software for Teaching the Sunpath Diagram and Shading Mask Protractor 

    E-Print Network [OSTI]

    Oh, J. K. W.; Haberl, J. S.

    1996-01-01

    software package that includes a tutorial on how the sunpath and shading mask protrotractor are constructed. protractor which represents the hemispherical view that one could obtained if a photo could be taken with a fisheye-lens camera that is facing...

  8. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOE Patents [OSTI]

    Hubbell, Earl A. (Mt. View, CA); Lipshutz, Robert J. (Palo Alto, CA); Morris, Macdonald S. (San Jose, CA); Winkler, James L. (Palo Alto, CA)

    1997-01-01

    An improved set of computer tools for forming arrays. According to one aspect of the invention, a computer system is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files to design and/or generate lithographic masks.

  9. Evaluation of MODIS snow cover and cloud mask and its application in Northern Xinjiang, China

    E-Print Network [OSTI]

    Texas at San Antonio, University of

    Evaluation of MODIS snow cover and cloud mask and its application in Northern Xinjiang, China in revised form 14 May 2007; accepted 26 May 2007 Abstract Using five-year (2001­2005) ground-observed snow the accuracy of the 8-day snow cover product (MOD10A2) from the Moderate Resolution Imaging Spectroradiometer

  10. Informational masking for simultaneous nonspeech stimuli: Psychometric functions for fixed and randomly mixed maskers

    E-Print Network [OSTI]

    Shinn-Cunningham, Barbara

    be reasonably well fit by simple energy-detector models in which internal noise and filter bandwidth are used of new data and its relation to energy-detector models, this paper provides comments on a variety target is being masked by a simultaneously presented multitone com- plex e.g., Neff and Green, 1987; Neff

  11. Analysis of a Mask-Based Nanowire Decoder Eric Rachlin, John E. Savage and Benjamin Gojman

    E-Print Network [OSTI]

    Savage, John

    a moderate number of mesoscale wires. Three methods have been proposed to use mesoscale wires to control random doped connections between nanowires and mesoscale wires, and the third, a mask-based approach, in- terposes high-K dielectric regions between nanowires and mesoscale wires. All three addressing schemes

  12. Thermal behavior of TAXN and TCDXM D2 collimator mask, Finite element studies

    E-Print Network [OSTI]

    Sklariks, Stepans

    2015-01-01

    The objective of this project was to perform thermal loading simulations of TCDXM (D2 collimator mask) and TAXN so as to allow the preliminary evaluation of the suitability of the given parts for the upcoming high luminosity upgrade that is to be performed in LHC in the nearest future.

  13. Title of Document: DEVELOPMENT OF AN ADAPTIVE MASKING METHOD TO IMAGE BEAM

    E-Print Network [OSTI]

    Anlage, Steven

    . Light produced by the beam intercepting a phosphor screen is first imaged onto the array; an adaptiveABSTRACT Title of Document: DEVELOPMENT OF AN ADAPTIVE MASKING METHOD TO IMAGE BEAM HALO Hao Zhang performed to study beam halo at the University of Maryland Electron Ring. #12;DEVELOPMENT OF AN ADAPTIVE

  14. Model Selection for the Competing-Risks Model With and Without Masking

    E-Print Network [OSTI]

    Lee, Thomas

    Department of Statistics Colorado State University Fort Collins, CO 80523-1877 (tlee@stat.colostate.edu) The competing-risks model is useful in settings in which individuals (or units) may die (or fail) because for competing-risks data with and without masking involves the specification of cause-specific hazard rates

  15. Automatic Selection of Mask and Arterial Phase Images for Temporally Resolved MR Digital

    E-Print Network [OSTI]

    Zabih, Ramin

    Automatic Selection of Mask and Arterial Phase Images for Temporally Resolved MR Digital Subtraction Angiography Junhwan Kim,1* Martin R. Prince,2 Ramin Zabih,1,2 Jeff Bezanson,2 Richard Watts,2 Hale angiography (CEMRA) has become a routine clinical tool for pretreat- ment mapping of vasculature (1). Among

  16. Can we stop the spread of influenza in schools with face masks?

    SciTech Connect (OSTI)

    Del Valle, Sara Y; Tellier, Raymond; Settles, Gary; Tang, Julian

    2009-01-01

    In the absence of a strain-specific vaccine and the potential resistance to antiviral medication, nonpharmaceutical interventions can be used to reduce the spread of an infectious disease such as influenza. The most common non-pharmaceutical interventions include school closures, travel restrictions, social distancing, enforced or volunteer home isolation and quarantine, improved hand hygiene, and the appropriate wearing of face masks. However, for some of these interventions, there are some unavoidable economic costs to both employees and employers, as well as possible additional detriment to society as a whole. For example, it has been shown that school-age children are most likely to be infected and act as sources of infection for others, due to their greater societal interaction and increased susceptibility. Therefore, preventing or at least reducing infections in children is a logical first-line of defense. For this reason, school closures have been widely investigated and recommended as part of pandemic influenza preparedness, and some studies support this conclusion. Yet, school closures would result in lost work days if at least one parent must be absent from work to care for children who would otherwise be at school. In addition, the delay in-academic progress may be detrimental due to mass school absenteeism. In particular, the pandemic influenza guidance by the U.S. Department of Health and Human Services recommends school closures for less than four weeks for Category 2 and 3 pandemics (i.e., similar to the milder 1957 and 1968 pandemics) and one to three months for Category 4 and 5 pandemics (i .e., similar to the 1918 pandemic ). Yet, given the above, it is clear that closing schools for up to three months is unlikely to be a practical mitigation strategy for many families and society. Thus modelers and policy makers need to weigh all factors before recommending such drastic measures, particularly if the agent under consideration typically has low mortality and causes a mild disease. Therefore, we contend that face masks are an effective, practical, non-pharmaceutical intervention that would reduce the spread of disease among school-children, while keeping schools open. Influenza spreads through person-to-person contact, via transmission by large droplets or aerosols (droplet nuclei) produced by breathing, talking, coughing or sneezing, as well as by direct (though most people touch very few others in their daily lives) or indirect (i.e., via fomites) contact. Face masks act as a physical barrier to reduce the amount of potentially infectious inhaled and exhaled particles, although they would not reliably protect the wearer against aerosols; a recent study also demonstrated that they can redirect and decelerate exhaled airflows (when worn by an infected individual) to prevent them from entering the breathing zones of others. Thus, if a whole classroom were to don face masks, disease transmission would be expected to be greatly diminished. Another recent study on face masks and hand hygiene show a 10-50% transmission reduction for influenza-like illnesses. Furthermore, face masks can act as an effective physical reminder and barrier to transmission by preventing the wearer from touching any potentially infectious secretions from their mucous membranes (i.e., from the nose and mouth), which is another mechanism for direct and indirect contact transmission for influenza. A recent systematic review has suggested that wearing masks can be highly effective in limiting the transmission of respiratory infections, such as influenza. Yet, admittedly, the effectiveness of this intervention strategy is highly dependent on compliance (i.e., the willingness to wear the mask in all appropriate situations), which in tum depends on comfort, convenience, fitness, and hygiene. Importantly, masks themselves must not become a source of infection (or reinfection); as such they should be replaced or sanitized daily (where possible) to maximize effectiveness. One solution could be for masks to be touted as fashion accessories, whi

  17. Simulation of localized barrier defects in resonant tunneling diodes 

    E-Print Network [OSTI]

    Stoneberg, Jason Neal

    1995-01-01

    defect assisted tunneling as a possible current mechanism. This study attempts to ascertain the effects of defect potentials in the barriers on current in a simulation of a double barrier resonant tunneling diode. Results indicate that these defects could...

  18. System and methods for determining masking signals for applying empirical mode decomposition (EMD) and for demodulating intrinsic mode functions obtained from application of EMD

    DOE Patents [OSTI]

    Senroy, Nilanjan (New Delhi, IN); Suryanarayanan, Siddharth (Littleton, CO)

    2011-03-15

    A computer-implemented method of signal processing is provided. The method includes generating one or more masking signals based upon a computed Fourier transform of a received signal. The method further includes determining one or more intrinsic mode functions (IMFs) of the received signal by performing a masking-signal-based empirical mode decomposition (EMD) using the at least one masking signal.

  19. Coulomb screening in graphene with topological defects

    E-Print Network [OSTI]

    Baishali Chakraborty; Kumar S. Gupta; Siddhartha Sen

    2015-02-20

    We analyze the screening of an external Coulomb charge in gapless graphene cone, which is taken as a prototype of a topological defect. In the subcritical regime, the induced charge is calculated using both the Green's function and the Friedel sum rule. The dependence of the polarization charge on the Coulomb strength obtained from the Green's function clearly shows the effect of the conical defect and indicates that the critical charge itself depends on the sample topology. Similar analysis using the Friedel sum rule indicates that the two results agree for low values of the Coulomb charge but differ for the higher strengths, especially in the presence of the conical defect. For a given subcritical charge, the transport cross-section has a higher value in the presence of the conical defect. In the supercritical regime we show that the coefficient of the power law tail of polarization charge density can be expressed as a summation of functions which vary log periodically with the distance from the Coulomb impurity. The period of variation depends on the conical defect. In the presence of the conical defect, the Fano resonances begin to appear in the transport cross-section for a lower value of the Coulomb charge. For both sub and supercritical regime we derive the dependence of LDOS on the conical defect. The effects of generalized boundary condition on the physical observables are also discussed.

  20. Symmetry fractionalization and twist defects

    E-Print Network [OSTI]

    Nicolas Tarantino; Netanel Lindner; Lukasz Fidkowski

    2015-06-22

    Topological order in two dimensions can be described in terms of deconfined quasiparticle excitations - anyons - and their braiding statistics. However, it has recently been realized that this data does not completely describe the situation in the presence of an unbroken global symmetry. In this case, there can be multiple distinct quantum phases with the same anyons and statistics, but with different patterns of symmetry fractionalization - termed symmetry enriched topological (SET) order. When the global symmetry group $G$, which we take to be discrete, does not change topological superselection sectors - i.e. does not change one type of anyon into a different type of anyon - one can imagine a local version of the action of $G$ around each anyon. This leads to projective representations and a group cohomology description of symmetry fractionalization, with $H^2(G,{\\cal A})$ being the relevant group. In this paper, we treat the general case of a symmetry group $G$ possibly permuting anyon types. We show that despite the lack of a local action of $G$, one can still make sense of a so-called twisted group cohomology description of symmetry fractionalization, and show how this data is encoded in the associativity of fusion rules of the extrinsic `twist' defects of the symmetry. Furthermore, building on work of Hermele, we construct a wide class of exactly solved models which exhibit this twisted symmetry fractionalization, and connect them to our formal framework.

  1. Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder These slides were presented at the Onboard...

  2. Characterization of structural defects in nuclear graphite IG...

    Office of Scientific and Technical Information (OSTI)

    Characterization of structural defects in nuclear graphite IG-110 and NBG-18 Citation Details In-Document Search Title: Characterization of structural defects in nuclear graphite...

  3. Di-interstitial defect in silicon revisited

    SciTech Connect (OSTI)

    Londos, C. A.; Antonaras, G.; Chroneos, A.; Department of Materials, Imperial College London, London SW7 2BP

    2013-11-21

    Infrared spectroscopy was used to study the defect spectrum of Cz-Si samples following fast neutron irradiation. We mainly focus on the band at 533 cm{sup ?1}, which disappears from the spectra at ?170 °C, exhibiting similar thermal stability with the Si-P6 electron paramagnetic resonance (EPR) spectrum previously correlated with the di-interstitial defect. The suggested structural model of this defect comprises of two self-interstitial atoms located symmetrically around a lattice site Si atom. The band anneals out following a first-order kinetics with an activation energy of 0.88 ± 0.3 eV. This value does not deviate considerably from previously quoted experimental and theoretical values for the di-interstitial defect. The present results indicate that the 533 cm{sup ?1} IR band originates from the same structure as that of the Si-P6 EPR spectrum.

  4. Thermodynamics of Cosmic Defect Network Evolution

    E-Print Network [OSTI]

    Avelino, P P

    2015-01-01

    We show that simple thermodynamic conditions determine, to a great extent, the equation of state and dynamics of cosmic defects of arbitrary dimensionality. We use these conditions to provide a more direct derivation of the Velocity-dependent One-Scale (VOS) model for the macroscopic dynamics of topological defects of arbitrary dimensionality in a $N+1$-dimensional homogeneous and isotropic universe. We parameterize the modifications to the VOS model associated to the interaction of the topological defects with other fields, including, in particular, a new dynamical degree of freedom associated to the variation of the mass per unit $p$-area of the defects, and compute the corresponding scaling solutions. The observational impact of this new dynamical degree of freedom is also briefly discussed.

  5. INNOVATIVE EDDY CURRENT PROBE FOR MICRO DEFECTS

    SciTech Connect (OSTI)

    Santos, Telmo G.; Vilaca, Pedro; Quintino, Luisa [IDMEC, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Santos, Jorge dos [GKSS, Max-Planck-Street 1, D-21502 Geesthacht (Germany); Rosado, Luis [IST, UTL, Av. Rovisco Pais, 1049-001 Lisbon (Portugal)

    2010-02-22

    This paper reports the development of an innovative eddy current (EC) probe, and its application to micro-defects on the root of the Friction Stir Welding (FSW). The new EC probe presents innovative concept issues, allowing 3D induced current in the material, and a lift-off independence. Validation experiments were performed on aluminium alloys processed by FSW. The results clearly show that the new EC probe is able to detect and sizing surface defects about 60 microns depth.

  6. Reflection and transmission of conformal perturbation defects

    E-Print Network [OSTI]

    Ilka Brunner; Cornelius Schmidt-Colinet

    2015-08-18

    We consider reflection and transmission of interfaces which implement renormalisation group flows between conformal fixed points in two dimensions. Such an RG interface is constructed from the identity defect in the ultraviolet CFT by perturbing the theory on one side of the defect line. We compute reflection and transmission coefficients in perturbation theory to third order in the coupling constant and check our calculations against exact constructions of RG interfaces between coset models.

  7. Reflection and transmission of conformal perturbation defects

    E-Print Network [OSTI]

    Brunner, Ilka

    2015-01-01

    We consider reflection and transmission of interfaces which implement renormalisation group flows between conformal fixed points in two dimensions. Such an RG interface is constructed from the identity defect in the ultraviolet CFT by perturbing the theory on one side of the defect line. We compute reflection and transmission coefficients in perturbation theory to third order in the coupling constant and check our calculations against exact constructions of RG interfaces between coset models.

  8. Intrinsic structural defects in monolayer molybdenum disulfide

    SciTech Connect (OSTI)

    Zhou, Wu [ORNL; Idrobo Tapia, Juan C [ORNL

    2013-01-01

    Monolayer molybdenum disulfide (MoS2) is a two-dimensional direct band gap semiconductor with distinctive mechanical, electronic, optical and chemical properties that can be utilized for novel nanoelectronics and optoelectronics devices. The performance of these electronic devices strongly depends on the quality and defect morphology of the MoS2 layers. Yet, little is known about the atomic structure of defects present in monolayer MoS2 and their influences on the material properties. Here we provide a systematic study of various intrinsic structural defects, including point defects, grain boundaries, and edges, in chemical vapor phase grown monolayer MoS2 via direct atomic resolution imaging, and explore their energy landscape and electronic properties using first-principles calculations. We discover that one-dimensional metallic wires can be created via two different types of 60 grain boundaries consisting of distinct 4-fold ring chains. A new type of edge reconstruction, representing a transition state during growth, was also identified, providing insights into the material growth mechanism. The atomic scale study of structural defects presented here brings new opportunities to tailor the properties of MoS2 via controlled synthesis and defect engineering.

  9. Optimized focal and pupil plane masks for vortex coronagraphs on telescopes with obstructed apertures

    E-Print Network [OSTI]

    Ruane, Garreth J; Huby, Elsa; Mawet, Dimitri; Delacroix, Christian; Carlomagno, Brunella; Piron, Pierre; Swartzlander, Grover A

    2015-01-01

    We present methods for optimizing pupil and focal plane optical elements that improve the performance of vortex coronagraphs on telescopes with obstructed or segmented apertures. Phase-only and complex masks are designed for the entrance pupil, focal plane, and the plane of the Lyot stop. Optimal masks are obtained using both analytical and numerical methods. The latter makes use of an iterative error reduction algorithm to calculate "correcting" optics that mitigate unwanted diffraction from aperture obstructions. We analyze the achieved performance in terms of starlight suppression, contrast, off-axis image quality, and chromatic dependence. Manufacturing considerations and sensitivity to aberrations are also discussed. This work provides a path to joint optimization of multiple coronagraph planes to maximize sensitivity to exoplanets and other faint companions.

  10. Patterned Exfoliation of GaAs Based on Masked Helium Implantation and Subsequent Rapid Thermal Annealing

    SciTech Connect (OSTI)

    Woo, H. J.; Choi, H. W.; Kim, G. D.; Hong, W.; Kim, J. K.

    2009-03-10

    A method of patterning single crystal GaAs based on ion implantation induced selective area exfoliation is suggested. Samples were implanted with 200-500 keV helium ions to a fluence range of 2-4x10{sup 16} He{sup +}/cm{sup 2} at room temperature through masks of Ni mesh (40 {mu}m opening) or stainless steel wire (50 {mu}m in diameter), and subsequent rapid thermal annealing at 350-500{open_square} resulted in expulsion of ion beam exposed material. The influences of ion energy, ion fluence, implantation temperature, subsequent annealing conditions (temperature and ramp rate), and mask pattern and its orientation with GaAs lattice on the patterned exfoliation were examined.

  11. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOE Patents [OSTI]

    Hubbell, E.A.; Morris, M.S.; Winkler, J.L.

    1999-01-05

    An improved set of computer tools for forming arrays is disclosed. According to one aspect of the invention, a computer system is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files to design and/or generate lithographic masks. 14 figs.

  12. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOE Patents [OSTI]

    Hubbell, E.A.; Morris, M.S.; Winkler, J.L.

    1996-11-05

    An improved set of computer tools for forming arrays is disclosed. According to one aspect of the invention, a computer system is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files to design and/or generate lithographic masks. 14 figs.

  13. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOE Patents [OSTI]

    Hubbell, Earl A. (Mt. View, CA); Morris, MacDonald S. (San Jose, CA); Winkler, James L. (Palo Alto, CA)

    1996-01-01

    An improved set of computer tools for forming arrays. According to one aspect of the invention, a computer system (100) is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files (104) to design and/or generate lithographic masks (110).

  14. Computer-aided engineering system for design of sequence arrays and lithographic masks

    DOE Patents [OSTI]

    Hubbell, Earl A. (Mt. View, CA); Morris, MacDonald S. (San Jose, CA); Winkler, James L. (Palo Alto, CA)

    1999-01-05

    An improved set of computer tools for forming arrays. According to one aspect of the invention, a computer system (100) is used to select probes and design the layout of an array of DNA or other polymers with certain beneficial characteristics. According to another aspect of the invention, a computer system uses chip design files (104) to design and/or generate lithographic masks (110).

  15. Planck CMB anomalies: astrophysical and cosmological secondary effects and the curse of masking

    SciTech Connect (OSTI)

    Rassat, A.; Starck, J.-L.; Paykari, P.; Sureau, F.; Bobin, J. E-mail: jstarck@cea.fr E-mail: florent.sureau@cea.fr

    2014-08-01

    Large-scale anomalies have been reported in CMB data with both WMAP and Planck data. These could be due to foreground residuals and or systematic effects, though their confirmation with Planck data suggests they are not due to a problem in the WMAP or Planck pipelines. If these anomalies are in fact primordial, then understanding their origin is fundamental to either validate the standard model of cosmology or to explore new physics. We investigate three other possible issues: 1) the trade-off between minimising systematics due to foreground contamination (with a conservative mask) and minimising systematics due to masking, 2) astrophysical secondary effects (the kinetic Doppler quadrupole and kinetic Sunyaev-Zel'dovich effect), and 3) secondary cosmological signals (the integrated Sachs-Wolfe effect). We address the masking issue by considering new procedures that use both WMAP and Planck to produce higher quality full-sky maps using the sparsity methodology (LGMCA maps). We show the impact of masking is dominant over that of residual foregrounds, and the LGMCA full-sky maps can be used without further processing to study anomalies. We consider four official Planck PR1 and two LGMCA CMB maps. Analysis of the observed CMB maps shows that only the low quadrupole and quadrupole-octopole alignment seem significant, but that the planar octopole, Axis of Evil, mirror parity and cold spot are not significant in nearly all maps considered. After subtraction of astrophysical and cosmological secondary effects, only the low quadrupole may still be considered anomalous, meaning the significance of only one anomaly is affected by secondary effect subtraction out of six anomalies considered. In the spirit of reproducible research all reconstructed maps and codes will be made available for download here http://www.cosmostat.org/anomaliesCMB.html.

  16. High numerical aperture ring field projection system for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Hudyma, Russell (218 Eastridge Dr., San Ramon, CA 94583-4905); Shafer, David (50 Drake La., Fairfield, CT 06430-2925)

    2001-01-01

    An all-reflective optical system for a projection photolithography camera has a source of EUV radiation, a wafer and a mask to be imaged on the wafer. The optical system includes a first convex mirror, a second mirror, a third convex mirror, a fourth concave mirror, a fifth convex mirror and a sixth concave mirror. The system is configured such that five of the six mirrors receives a chief ray at an incidence angle of less than substantially 9.degree., and each of the six mirrors receives a chief ray at an incidence angle of less than substantially 14.degree.. Four of the six reflecting surfaces have an aspheric departure of less than substantially 12 .mu.m. Five of the six reflecting surfaces have an aspheric departure of less than substantially 12 .mu.m. Each of the six reflecting surfaces has an aspheric departure of less than substantially 16 .mu.m.

  17. High numerical aperture ring field projection system for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Hudyma, Russell (315 Eastridge Dr., San Ramon, CA 94583-4905)

    2001-01-01

    An all-reflective optical system for a projection photolithography camera has a source of EUV radiation, a wafer and a mask to be imaged on the wafer. The optical system includes a first concave mirror, a second mirror, a third convex mirror, a fourth concave mirror, a fifth convex mirror and a sixth concave mirror. The system is configured such that five of the six mirrors receives a chief ray at an incidence angle of less than substantially 12.degree., and each of the six mirrors receives a chief ray at an incidence angle of less than substantially 15.degree.. Four of the six reflecting surfaces have an aspheric departure of less than substantially 7 .mu.m. Five of the six reflecting surfaces have an aspheric departure of less than substantially 14 .mu.m. Each of the six reflecting surfaces has an aspheric departure of less than 16.0 .mu.m.

  18. High numerical aperture ring field projection system for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Hudyma, Russell (218 Eastridge Dr., San Ramon, CA 84583-4905)

    2000-01-01

    An all-refelctive optical system for a projection photolithography camera has a source of EUV radiation, a wafer and a mask to be imaged on the wafer. The optical system includes a first concave mirror, a second mirror, a third convex mirror, a fourth concave mirror, a fifth convex mirror and a sixth concave mirror. The system is configured such that five of the six mirrors receives a chief ray at an incidence angle less than substantially 12.degree., and each of the six mirrors receives a chief ray at an incidence angle of less than substantially 15.degree.. Four of the six reflecting surfaces have an aspheric departure of less than substantially 7 .mu.m. Five of the six reflecting surfaces have an aspheric departure of less than substantially 14 .mu.m. Each of the six refelecting surfaces has an aspheric departure of less than 16.0 .mu.m.

  19. High numerical aperture ring field projection system for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Hudyma, Russell (218 Eastridge Dr., San Ramon, CA 94583-4905); Shafer, David R. (56 Drake La., Fairfield, CT 06430-2925)

    2001-01-01

    An all-reflective optical system for a projection photolithography camera has a source of EUV radiation, a wafer and a mask to be imaged on the wafer. The optical system includes a first convex mirror, a second mirror, a third convex mirror, a fourth concave mirror, a fifth convex mirror and a sixth concave mirror. The system is configured such that five of the six mirrors receive a chief ray at an incidence angle of less than substantially 9.degree., and each of the six mirrors receives a chief ray at an incidence angle of less than substantially 14.degree.. Four of the six reflecting surfaces have an aspheric departure of less than substantially 12 .mu.m. Five of the six reflecting surfaces have an aspheric departure of less than substantially 12 .mu.m. Each of the six reflecting surfaces has an aspheric departure of less than substantially 16 .mu.m.

  20. Assessing out-of-band flare effects at the wafer level for EUV lithography

    SciTech Connect (OSTI)

    George, Simi; Naulleau, Patrick; Kemp, Charles; Denham, Paul; Rekawa, Senajith

    2010-01-25

    To accurately estimate the flare contribution from the out-of-band (OOB), the integration of a DUV source into the SEMATECH Berkeley 0.3-NA Micro-field Exposure tool is proposed, enabling precisely controlled exposures along with the EUV patterning of resists in vacuum. First measurements evaluating the impact of bandwidth selected exposures with a table-top set-up and subsequent EUV patterning show significant impact on line-edge roughness and process performance. We outline a simulation-based method for computing the effective flare from resist sensitive wavelengths as a function of mask pattern types and sizes. This simulation method is benchmarked against measured OOB flare measurements and the results obtained are in agreement.

  1. Masked priming and ERPs dissociate maturation of orthographic and semantic components of visual word recognition in children

    E-Print Network [OSTI]

    Eddy, Marianna D.

    This study examined the time-course of reading single words in children and adults using masked repetition priming and the recording of event-related potentials. The N250 and N400 repetition priming effects were used to ...

  2. Two-dimensional defect modes in optically induced photonic lattices

    SciTech Connect (OSTI)

    Wang Jiandong; Yang Jianke; Chen Zhigang [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401 (United States); Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States)

    2007-07-15

    In this article, localized linear defect modes due to band gap guidance in two-dimensional photonic lattices with localized or nonlocalized defects are investigated theoretically. First, when the defect is localized and weak, eigenvalues of defect modes bifurcated from edges of Bloch bands are derived analytically. It is shown that in an attractive (repulsive) defect, defect modes bifurcate out from Bloch-band edges with normal (anomalous) diffraction coefficients. Furthermore, distances between defect-mode eigenvalues and Bloch-band edges decrease exponentially with the defect strength, which is very different from the one-dimensional case where such distances decrease quadratically with the defect strength. It is also found that some defect-mode branches bifurcate not from Bloch-band edges, but from quasiedge points within Bloch bands, which is very unusual. Second, when the defect is localized but strong, defect modes are determined numerically. It is shown that both the repulsive and attractive defects can support various types of defect modes such as fundamental, dipole, quadrupole, and vortex modes. These modes reside in various band gaps of the photonic lattice. As the defect strength increases, defect modes move from lower band gaps to higher ones when the defect is repulsive, but remain within each band gap when the defect is attractive, similar to the one-dimensional case. The same phenomena are observed when the defect is held fixed while the applied dc field (which controls the lattice potential) increases. Lastly, if the defect is nonlocalized (i.e., it persists at large distances in the lattice), it is shown that defect modes can be embedded inside the continuous spectrum, and they can bifurcate out from edges of the continuous spectrum algebraically rather than exponentially.

  3. Femtosecond-laser Microstructuring of Silicon: Dopants and Defects

    E-Print Network [OSTI]

    Mazur, Eric

    -laser Microstructuring of Silicon: Dopants and Defects Cynthia Friend Michael A. Sheehy Abstract This dissertation deals

  4. Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects

    E-Print Network [OSTI]

    1 Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects Jared W. Nelson The Blade Reliability Collaborative has been formed to perform comprehensive studies to improve wind turbine uni-directional wind turbine fiber-reinforced composite material with an epoxy resin were utilized

  5. A topological point defect regulates the evolution of extended defects in irradiated silicon

    E-Print Network [OSTI]

    Wilkins, John

    functional theory calculations establish formation energies, activation barriers, and electronic structures structure. Compared to the experimental gap of 1.16 eV for bulk Si,16 the calculated HSE gap, 1.15 eV, shows interstitial defects in irradiated silicon. Molecular dynamics simulations reveal the role of the bond defect

  6. Hovering Black Holes from Charged Defects

    E-Print Network [OSTI]

    Gary T. Horowitz; Nabil Iqbal; Jorge E. Santos; Benson Way

    2015-05-05

    We construct the holographic dual of an electrically charged, localised defect in a conformal field theory at strong coupling, by applying a spatially dependent chemical potential. We find that the IR behaviour of the spacetime depends on the spatial falloff of the potential. Moreover, for sufficiently localized defects with large amplitude, we find that a new gravitational phenomenon occurs: a spherical extremal charged black hole nucleates in the bulk: a hovering black hole. This is a second order quantum phase transition. We construct this new phase with several profiles for the chemical potential and study its properties. We find an apparently universal behaviour for the entropy of the defect as a function of its amplitude. We comment on the possible field theory implications of our results.

  7. Elastic interactions between 2D geometric defects

    E-Print Network [OSTI]

    Michael Moshe; Eran Sharon; Raz Kupferman

    2015-10-13

    In this paper, we introduce a methodology applicable to a wide range of localized two-dimensional sources of stress. This methodology is based on a geometric formulation of elasticity. Localized sources of stress are viewed as singular defects---point charges of the curvature associated with a reference metric. The stress field in the presence of defects can be solved using a scalar stress function that generalizes the classical Airy stress function to the case of materials with nontrivial geometry. This approach allows the calculation of interaction energies between various types of defects. We apply our methodology to two physical systems: shear-induced failure of amorphous materials and the mechanical interaction between contracting cells.

  8. Bistable defect structures in blue phase devices

    E-Print Network [OSTI]

    A. Tiribocchi; G. Gonnella; D. Marenduzzo; E. Orlandini; F. Salvadore

    2011-10-28

    Blue phases (BPs) are liquid crystals made up by networks of defects, or disclination lines. While existing phase diagrams show a striking variety of competing metastable topologies for these networks, very little is known as to how to kinetically reach a target structure, or how to switch from one to the other, which is of paramount importance for devices. We theoretically identify two confined blue phase I systems in which by applying an appropriate series of electric field it is possible to select one of two bistable defect patterns. Our results may be used to realise new generation and fast switching energy-saving bistable devices in ultrathin surface treated BPI wafers.

  9. GaN: Defect and Device Issues

    SciTech Connect (OSTI)

    Pearton, S.J.; Ren, F.; Shul, R.J.; Zolper, J.C.

    1998-11-09

    The role of extended and point defects, and key impurities such as C, O and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.

  10. The effects of fastener hole defects 

    E-Print Network [OSTI]

    Andrews, Scot D.

    1991-01-01

    ) August 1991 ABSTRACT The Effects of Fastener Hole Defects. (August 1991) Scot D. Andrews, B. S. , Texas A8rM University Chair of Advisory Committee: Dr. Orden O. Ochoa The influence of drilling-induced defects, such as delamination, on the fatigue... ambient and elevated temperature wet conditions. Specimens were tested in a bearing tension frame to static failure in order to measure the failure load and to calculate pin bearing stress. From static test results, a fatigue load was selected as 66...

  11. Point Defect Dynamics in Two-Dimensional Colloidal Crystals

    E-Print Network [OSTI]

    A. Libal; C. Reichhardt; C. J. Olson Reichhardt

    2006-12-16

    We study the topological configurations and dynamics of individual point defect vacancies and interstitials in a two-dimensional colloidal crystal. Our Brownian dynamics simulations show that the diffusion mechanism for vacancy defects occurs in two phases. The defect can glide along the crystal lattice directions, and it can rotate during an excited topological transition configuration to assume a different direction for the next period of gliding. The results for the vacancy defects are in good agreement with recent experiments. For the interstitial point defects, which were not studied in the experiments, we find several of the same modes of motion as in the vacancy defect case along with two additional diffusion pathways. The interstitial defects are more mobile than the vacancy defects due to the more two-dimensional nature of the diffusion of the interstitial defects.

  12. Gas Mask 

    E-Print Network [OSTI]

    Unknown

    2011-09-05

    The gas industry fostered more efficient energy utilization long before the idea of energy conservation became fashionable. It became apparent in the late '60's that misguided Federal Legislation was discouraging necessary search for new gas...

  13. Wavelet-Smoothed Interpolation of Masked Scientific Data for JPEG 2000 Compression

    SciTech Connect (OSTI)

    Brislawn, Christopher M. [Los Alamos National Laboratory

    2012-08-13

    How should we manage scientific data with 'holes'? Some applications, like JPEG 2000, expect logically rectangular data, but some sources, like the Parallel Ocean Program (POP), generate data that isn't defined on certain subsets. We refer to grid points that lack well-defined, scientifically meaningful sample values as 'masked' samples. Wavelet-smoothing is a highly scalable interpolation scheme for regions with complex boundaries on logically rectangular grids. Computation is based on forward/inverse discrete wavelet transforms, so runtime complexity and memory scale linearly with respect to sample count. Efficient state-of-the-art minimal realizations yield small constants (O(10)) for arithmetic complexity scaling, and in-situ implementation techniques make optimal use of memory. Implementation in two dimensions using tensor product filter banks is straighsorward and should generalize routinely to higher dimensions. No hand-tuning required when the interpolation mask changes, making the method aeractive for problems with time-varying masks. Well-suited for interpolating undefined samples prior to JPEG 2000 encoding. The method outperforms global mean interpolation, as judged by both SNR rate-distortion performance and low-rate artifact mitigation, for data distributions whose histograms do not take the form of sharply peaked, symmetric, unimodal probability density functions. These performance advantages can hold even for data whose distribution differs only moderately from the peaked unimodal case, as demonstrated by POP salinity data. The interpolation method is very general and is not tied to any particular class of applications, could be used for more generic smooth interpolation.

  14. Fabrication of triangular nanobeam waveguide networks in bulk diamond using single-crystal silicon hard masks

    SciTech Connect (OSTI)

    Bayn, I.; Mouradian, S.; Li, L.; Goldstein, J. A.; Schröder, T.; Zheng, J.; Chen, E. H.; Gaathon, O.; Englund, Dirk; Lu, M.; Stein, A.; Ruggiero, C. A.; Salzman, J.; Kalish, R.

    2014-11-24

    A scalable approach for integrated photonic networks in single-crystal diamond using triangular etching of bulk samples is presented. We describe designs of high quality factor (Q?=?2.51?×?10{sup 6}) photonic crystal cavities with low mode volume (V{sub m}?=?1.062?×?(?/n){sup 3}), which are connected via waveguides supported by suspension structures with predicted transmission loss of only 0.05?dB. We demonstrate the fabrication of these structures using transferred single-crystal silicon hard masks and angular dry etching, yielding photonic crystal cavities in the visible spectrum with measured quality factors in excess of Q?=?3?×?10{sup 3}.

  15. Patterned graphene functionalization via mask-free scanning of micro-plasma jet under ambient condition

    SciTech Connect (OSTI)

    Ye, Dong; Yu, Yao Liu, Lin; Wu, Shu-Qun; Lu, Xin-Pei; Wu, Yue

    2014-03-10

    In this work, a mask-free method is introduced for patterned nitrogen doping of graphene using a micro-plasma jet under ambient condition. Raman and X-ray photoelectron spectroscopy spectra indicate that nitrogen atoms are incorporated into the graphene lattice with the two-dimensional spatial distribution precisely controlled in the range of mm down to 10??m. Since the chemistry of the micro-plasma jet can be controlled by the choice of the gas mixture, this direct writing process with micro-plasma jet can be a versatile approach for patterned functionalization of graphene with high spatial resolution. This could have promising applications in graphene-based electronics.

  16. Defect Analysis of Vehicle Compressed Natural Gas

    E-Print Network [OSTI]

    Cylinder, translated and presented by J. P. Hsu, PhD, Smart Chemistry #12;Reason for Defect Analysis of CNG Composite Cylinder · Safety Issue - Four explosion accidents of auto used CNG composite material cylinders resulting huge personnel and vehicles loss. · Low Compliance Rate ­ Inspect 12119 Auto used CNG composite

  17. Premelting at Defects Within Bulk Colloidal Crystals

    E-Print Network [OSTI]

    Collings, Peter

    Premelting at Defects Within Bulk Colloidal Crystals A. M. Alsayed,1 M. F. Islam,1 J. Zhang,1 P. J at grain boundaries and dislocations within bulk colloidal crystals using real- time video microscopy. The crystals are equilibrium close-packed, three- dimensional colloidal structures made from thermally

  18. Defect-free ultrahigh flux asymmetric membranes

    DOE Patents [OSTI]

    Pinnau, Ingo (Austin, TX); Koros, William J. (Austin, TX)

    1990-01-01

    Defect-free, ultrahigh flux integrally-skinned asymmetric membranes having extremely thin surface layers (<0.2 .mu.m) comprised of glassy polymers are disclosed. The membranes are formed by casting an appropriate drope followed by forced convective evaporation of solvent to obtain a dry phase separated asymmetrical structure. The structure is then washed in a precipitation liquid and dried.

  19. Development of computer program ENMASK for prediction of residual environmental masking-noise spectra, from any three independent environmental parameters

    SciTech Connect (OSTI)

    Chang, Y.-S.; Liebich, R. E.; Chun, K. C.

    2000-03-31

    Residual environmental sound can mask intrusive4 (unwanted) sound. It is a factor that can affect noise impacts and must be considered both in noise-impact studies and in noise-mitigation designs. Models for quantitative prediction of sensation level (audibility) and psychological effects of intrusive noise require an input with 1/3 octave-band spectral resolution of environmental masking noise. However, the majority of published residual environmental masking-noise data are given with either octave-band frequency resolution or only single A-weighted decibel values. A model has been developed that enables estimation of 1/3 octave-band residual environmental masking-noise spectra and relates certain environmental parameters to A-weighted sound level. This model provides a correlation among three environmental conditions: measured residual A-weighted sound-pressure level, proximity to a major roadway, and population density. Cited field-study data were used to compute the most probable 1/3 octave-band sound-pressure spectrum corresponding to any selected one of these three inputs. In turn, such spectra can be used as an input to models for prediction of noise impacts. This paper discusses specific algorithms included in the newly developed computer program ENMASK. In addition, the relative audibility of the environmental masking-noise spectra at different A-weighted sound levels is discussed, which is determined by using the methodology of program ENAUDIBL.

  20. Meningeal Defects alter the tangential migration of cortical interneurons in Foxc1hith/hith mice

    E-Print Network [OSTI]

    Zarbalis, Konstantinos; Choe, Youngshik; Siegenthaler, Julie A; Orosco, Lori A; Pleasure, Samuel J

    2012-01-01

    migration presents the primary mode of migration of corticalbe the primary cause for the observed migration defects.tangen- tial migration defects being a primary defect rather

  1. Healing of defects in a two-dimensional granular crystal

    E-Print Network [OSTI]

    Rice, Marie C

    2014-01-01

    Using a macroscopic analog for a two dimensional hexagonal crystal, we perform an experimental investigation of the self-healing properties of circular grain defects with an emphasis on defect orientation. A circular grain ...

  2. Estimating the expected latency to failure due to manufacturing defects 

    E-Print Network [OSTI]

    Dorsey, David Michael

    2004-09-30

    Manufacturers of digital circuits test their products to find defective parts so they are not sold to customers. Despite extensive testing, some of their products that are defective pass the testing process. To combat ...

  3. Defect site prediction based upon statistical analysis of fault signatures 

    E-Print Network [OSTI]

    Trinka, Michael Robert

    2004-09-30

    Good failure analysis is the ability to determine the site of a circuit defect quickly and accurately. We propose a method for defect site prediction that is based on a site's probability of excitation, making no assumptions about the type...

  4. Sandia Energy - Research Challenge 4: Defect-Carrier Interactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    technology challenges. research-challenge-4-defect-carrier-interactions-5001 Measured density of an InGaN quantum well (QW) deep-level defect located 0.15 eV above the valence...

  5. The pilus usher controls protein interactions via domain masking and is functional as an oligomer

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Werneburg, Glenn T.; Li, Huilin; Henderson, Nadine S.; Portnoy, Erica B.; Sarowar, Samema; Hultgren, Scott J.; Thanassi, David G.

    2015-06-08

    The chaperone/usher (CU) pathway is responsible for biogenesis of organelles termed pili or fimbriae in Gram-negative bacteria. Type 1 pili expressed by uropathogenic Escherichia coli are prototypical structures assembled by the CU pathway. Assembly and secretion of pili by the CU pathway requires a dedicated periplasmic chaperone and a multidomain outer membrane protein termed the usher (FimD). We show that the FimD C-terminal domains provide the high-affinity substrate binding site, but that these domains are masked in the resting usher. Domain masking requires the FimD plug domain, which served as a central switch controlling usher activation. In addition, we demonstratemore »that usher molecules can act in trans for pilus biogenesis, providing conclusive evidence for a functional usher oligomer. These results reveal mechanisms by which molecular machines such as the usher regulate and harness protein-protein interactions, and suggest that ushers may interact in a cooperative manner during pilus assembly in bacteria.« less

  6. Sub-50 nm scratch-proof DLC molds for reversal nanoimprint lithography L. Tao, C. T. Nelson, K. Trivedi, S. Ramachandran, M. Goeckner, L. Overzet, and Walter Hua)

    E-Print Network [OSTI]

    Hu, Wenchuang "Walter"

    Sub-50 nm scratch-proof DLC molds for reversal nanoimprint lithography L. Tao, C. T. Nelson, K of the industry is related to the mold life time that significantly affects cost of ownership and manufacturing reproducibility. Nowadays, most often used Si or glass molds that are very expensive can be damaged after certain

  7. Evaluating Static Analysis Defect Warnings On Production Software

    E-Print Network [OSTI]

    Cortes, Corinna

    , software quality 1. Introduction Static analysis for software defect detection has become a popular topicEvaluating Static Analysis Defect Warnings On Production Software Nathaniel Ayewah, William Pugh,jpenix,zhou@google.com Abstract Static analysis tools for software defect detection are becoming widely used in practice. However

  8. Clustering Static Analysis Defect Reports to Reduce Maintenance Costs

    E-Print Network [OSTI]

    Weimer, Westley

    Clustering Static Analysis Defect Reports to Reduce Maintenance Costs Zachary P. Fry and Westley, for large systems, these tools often produce an overwhelming number of defect reports. Many of these defect reports are conceptually similar, but addressing each report separately costs developer effort

  9. Modeling defective part level due to static and dynamic defects based upon site observation and excitation balance 

    E-Print Network [OSTI]

    Dworak, Jennifer Lynn

    2004-09-30

    a subset that detects a high percentage of the defective parts and produces a low defective part level. Historically, test pattern generation has often been seen as a deterministic endeavor. Test sets are generated to deterministically ensure that a...

  10. Transport on a Lattice with Dynamical Defects

    E-Print Network [OSTI]

    Francesco Turci; Andrea Parmeggiani; Estelle Pitard; M. Carmen Romano; Luca Ciandrini

    2013-01-10

    Many transport processes in nature take place on substrates, often considered as unidimensional lanes. These unidimensional substrates are typically non-static: affected by a fluctuating environment, they can undergo conformational changes. This is particularly true in biological cells, where the state of the substrate is often coupled to the active motion of macromolecular complexes, such as motor proteins on microtubules or ribosomes on mRNAs, causing new interesting phenomena. Inspired by biological processes such as protein synthesis by ribosomes and motor protein transport, we introduce the concept of localized dynamical sites coupled to a driven lattice gas dynamics. We investigate the phenomenology of transport in the presence of dynamical defects and find a novel regime characterized by an intermittent current and subject to severe finite-size effects. Our results demonstrate the impact of the regulatory role of the dynamical defects in transport, not only in biology but also in more general contexts.

  11. The ATLAS Data Quality Defect Database System

    E-Print Network [OSTI]

    T. Golling; H. S. Hayward; P. U. E. Onyisi; H. J. Stelzer; P. Waller

    2012-05-14

    The ATLAS experiment at the Large Hadron Collider has implemented a new system for recording information on detector status and data quality, and for transmitting this information to users performing physics analysis. This system revolves around the concept of "defects," which are well-defined, fine-grained, unambiguous occurrences affecting the quality of recorded data. The motivation, implementation, and operation of this system is described.

  12. Dark matter from decaying topological defects

    SciTech Connect (OSTI)

    Hindmarsh, Mark [Helsinki Institute of Physics, Gustaf Hällströmin katu, P.O. Box 64, 00014 Helsinki University (Finland); Kirk, Russell; West, Stephen M., E-mail: m.b.hindmarsh@sussex.ac.uk, E-mail: russell.kirk.2008@live.rhul.ac.uk, E-mail: stephen.west@rhul.ac.uk [Dept. of Physics, Royal Holloway University of London, Egham Hill, Egham, Surrey, TW20 0EX (United Kingdom)

    2014-03-01

    We study dark matter production by decaying topological defects, in particular cosmic strings. In topological defect or ''top-down'' (TD) scenarios, the dark matter injection rate varies as a power law with time with exponent p?4. We find a formula in closed form for the yield for all p < 3/2, which accurately reproduces the solution of the Boltzmann equation. We investigate two scenarios (p = 1, p = 7/6) motivated by cosmic strings which decay into TeV-scale states with a high branching fraction into dark matter particles. For dark matter models annihilating either by s-wave or p-wave, we find the regions of parameter space where the TD model can account for the dark matter relic density as measured by Planck. We find that topological defects can be the principal source of dark matter, even when the standard freeze-out calculation under-predicts the relic density and hence can lead to potentially large ''boost factor'' enhancements in the dark matter annihilation rate. We examine dark matter model-independent limits on this scenario arising from unitarity and discuss example model-dependent limits coming from indirect dark matter search experiments. In the four cases studied, the upper bound on G? for strings with an appreciable channel into TeV-scale states is significantly more stringent than the current Cosmic Microwave Background limits.

  13. A single-molecule approach to ZnO defect studies: Single photons and single defects

    SciTech Connect (OSTI)

    Jungwirth, N. R.; Pai, Y. Y.; Chang, H. S.; MacQuarrie, E. R.; Nguyen, K. X.; Fuchs, G. D.

    2014-07-28

    Investigations that probe defects one at a time offer a unique opportunity to observe properties and dynamics that are washed out of ensemble measurements. Here, we present confocal fluorescence measurements of individual defects in ZnO nanoparticles and sputtered films that are excited with sub-bandgap energy light. Photon correlation measurements yield both antibunching and bunching, indicative of single-photon emission from isolated defects that possess a metastable shelving state. The single-photon emission is in the range of ?560–720?nm and typically exhibits two broad spectral peaks separated by ?150?meV. The excited state lifetimes range from 1 to 13?ns, consistent with the finite-size and surface effects of nanoparticles and small grains. We also observe discrete jumps in the fluorescence intensity between a bright state and a dark state. The dwell times in each state are exponentially distributed and the average dwell time in the bright (dark) state does (may) depend on the power of the exciting laser. Taken together, our measurements demonstrate the utility of a single-molecule approach to semiconductor defect studies and highlight ZnO as a potential host material for single-defect based applications.

  14. Transport by molecular motors in the presence of static defects

    E-Print Network [OSTI]

    Yan Chai; Reinhard Lipowsky; Stefan Klumpp

    2009-05-07

    The transport by molecular motors along cytoskeletal filaments is studied theoretically in the presence of static defects. The movements of single motors are described as biased random walks along the filament as well as binding to and unbinding from the filament. Three basic types of defects are distinguished, which differ from normal filament sites only in one of the motors' transition probabilities. Both stepping defects with a reduced probability for forward steps and unbinding defects with an increased probability for motor unbinding strongly reduce the velocities and the run lengths of the motors with increasing defect density. For transport by single motors, binding defects with a reduced probability for motor binding have a relatively small effect on the transport properties. For cargo transport by motors teams, binding defects also change the effective unbinding rate of the cargo particles and are expected to have a stronger effect.

  15. The role of point defects and defect complexes in silicon device processing. Summary report and papers

    SciTech Connect (OSTI)

    Sopori, B.; Tan, T.Y.

    1994-08-01

    This report is a summary of a workshop hold on August 24--26, 1992. Session 1 of the conference discussed characteristics of various commercial photovoltaic silicon substrates, the nature of impurities and defects in them, and how they are related to the material growth. Session 2 on point defects reviewed the capabilities of theoretical approaches to determine equilibrium structure of defects in the silicon lattice arising from transitional metal impurities and hydrogen. Session 3 was devoted to a discussion of the surface photovoltaic method for characterizing bulk wafer lifetimes, and to detailed studies on the effectiveness of various gettering operations on reducing the deleterious effects of transition metals. Papers presented at the conference are also included in this summary report.

  16. Statistics of non-affine defect precursors: tailoring defect densities in colloidal crystals using external fields

    E-Print Network [OSTI]

    Saswati Ganguly; Surajit Sengupta; Peter Sollich

    2015-01-30

    Coarse-graining atomic displacements in a solid produces both local affine strains and "non-affine" fluctuations. Here we study the equilibrium dynamics of these coarse grained quantities to obtain space-time dependent correlation functions. We show how a subset of these thermally excited, non-affine fluctuations act as precursors for the nucleation of lattice defects and suggest how defect probabilities may be altered by an {\\it experimentally realisable} "external" field conjugate to the global non-affinity parameter. Our results are amenable to verification in experiments on colloidal crystals using commonly available holographic laser tweezer and video microscopy techniques, and may lead to simple ways of controlling the defect density of a colloidal solid.

  17. A NEW ALGORITHM FOR RADIOISOTOPE IDENTIFICATION OF SHIELDED AND MASKED SNM/RDD MATERIALS

    SciTech Connect (OSTI)

    Jeffcoat, R.

    2012-06-05

    Detection and identification of shielded and masked nuclear materials is crucial to national security, but vast borders and high volumes of traffic impose stringent requirements for practical detection systems. Such tools must be be mobile, and hence low power, provide a low false alarm rate, and be sufficiently robust to be operable by non-technical personnel. Currently fielded systems have not achieved all of these requirements simultaneously. Transport modeling such as that done in GADRAS is able to predict observed spectra to a high degree of fidelity; our research is focusing on a radionuclide identification algorithm that inverts this modeling within the constraints imposed by a handheld device. Key components of this work include incorporation of uncertainty as a function of both the background radiation estimate and the hypothesized sources, dimensionality reduction, and nonnegative matrix factorization. We have partially evaluated performance of our algorithm on a third-party data collection made with two different sodium iodide detection devices. Initial results indicate, with caveats, that our algorithm performs as good as or better than the on-board identification algorithms. The system developed was based on a probabilistic approach with an improved approach to variance modeling relative to past work. This system was chosen based on technical innovation and system performance over algorithms developed at two competing research institutions. One key outcome of this probabilistic approach was the development of an intuitive measure of confidence which was indeed useful enough that a classification algorithm was developed based around alarming on high confidence targets. This paper will present and discuss results of this novel approach to accurately identifying shielded or masked radioisotopes with radiation detection systems.

  18. Many roads lead to recognition: Electrophysiological correlates of familiarity derived from short-term masked repetition priming

    E-Print Network [OSTI]

    Henson, Rik

    cues via masked repetition priming. Replicating previous findings, the proportion of words endorsed; Norman, 2010; Shiffrin & Steyvers, 1997). As such, patterns of neural activity that vary continuously, it has been argued that recollection can also be graded or continuous, such that familiarity and weak

  19. USER EVALUATION OF THE MASK KIOSK L. Lamel, S. Bennacef, J.L. Gauvain, H. Dartiguesy, J.N. Tememy

    E-Print Network [OSTI]

    USER EVALUATION OF THE MASK KIOSK L. Lamel, S. Bennacef, J.L. Gauvain, H. Dartiguesy, J.N. Tememy with the French Railways (SNCF) and the Ergonomics group at the University College of London (UCL). The time) and the Ergonomics group at UCL (University College London). The physical design of the prototype kiosk has been

  20. Soft Harmonic Masks for Recognising Speech in the Presence of a Competing Andre Coy and Jon Barker

    E-Print Network [OSTI]

    Barker, Jon

    energy cannot be reliably labelled as either one source or the other. This typically happens whenSoft Harmonic Masks for Recognising Speech in the Presence of a Competing Speaker Andr´e Coy of recognising speech in the presence of a competing speaker. It uses a two stage `Speech Fragment Decoding

  1. Wavelength Invariant Bi/In Thermal Resist As A Si Anisotropic Etch Masking Layer And Direct Write Photomask Material

    E-Print Network [OSTI]

    Chapman, Glenn H.

    . Thermal modeling has confirmed the exposure time/optical energy requirements for Bi/In. Exposed these problems: an inorganic based resist activated by optically driven thermal processes, i.e. a thermal resistWavelength Invariant Bi/In Thermal Resist As A Si Anisotropic Etch Masking Layer And Direct Write

  2. Analysis of Mask-Based Nanowire Decoders Eric Rachlin, Student Member, IEEE, and John E. Savage, Life Fellow, IEEE

    E-Print Network [OSTI]

    Savage, John

    is controlling parallel sets of nanowires (NWs), such as those in crossbars, using a moderate number of mesoscale wires. Three similar methods have been proposed to control NWs using a set of perpendicular mesoscale between NWs and mesoscale wires, and the third, a mask-based approach, interposes high-K dielectric

  3. Good Halftone Masks via Genetic Algorithms Peter G. Anderson, Jonathan S. Arney, Samuel A. Inverso, Daniel R. Kunkle,

    E-Print Network [OSTI]

    Anderson, Peter G.

    of relatively poor individuals to keep the popula- tion size constant. It mutates then evaluates the new individuals. This process terminates after a predetermined time or when a satisfactory individual appears. GAs figure of merit ex- presses how well a mask renders a constant gray image--from the point of view

  4. Fast Yield-Driven Fracture for Variable Shaped-Beam Mask Andrew B. Kahng, Xu Xu and Alex Zelikovsky

    E-Print Network [OSTI]

    Zelikovsky, Alexander

    Fast Yield-Driven Fracture for Variable Shaped-Beam Mask Writing Andrew B. Kahng, Xu Xu and Alex process generation have collectively presented new challenges for current fracture tools, which-dimension errors. Some commercial tools are available for handling the sliver minimization problem in fracture

  5. Method of identifying defective particle coatings

    DOE Patents [OSTI]

    Cohen, Mark E. (San Diego, CA); Whiting, Carlton D. (San Diego, CA)

    1986-01-01

    A method for identifying coated particles having defective coatings desig to retain therewithin a build-up of gaseous materials including: (a) Pulling a vacuum on the particles; (b) Backfilling the particles at atmospheric pressure with a liquid capable of wetting the exterior surface of the coated particles, said liquid being a compound which includes an element having an atomic number higher than the highest atomic number of any element in the composition which forms the exterior surface of the particle coating; (c) Drying the particles; and (d) Radiographing the particles. By television monitoring, examination of the radiographs is substantially enhanced.

  6. Structural phase transitions and topological defects in ion Coulomb crystals

    SciTech Connect (OSTI)

    Partner, Heather L.; Nigmatullin, Ramil; Burgermeister, Tobias; Keller, Jonas; Pyka, Karsten; Plenio, Martin B.; Retzker, Alex; Zurek, Wojciech Hubert; del Campo, Adolfo; Mehlstaubler, Tanja E.

    2014-11-19

    We use laser-cooled ion Coulomb crystals in the well-controlled environment of a harmonic radiofrequency ion trap to investigate phase transitions and defect formation. Topological defects in ion Coulomb crystals (kinks) have been recently proposed for studies of nonlinear physics with solitons and as carriers of quantum information. Defects form when a symmetry breaking phase transition is crossed non-adiabatically. For a second order phase transition, the Kibble-Zurek mechanism predicts that the formation of these defects follows a power law scaling in the rate of the transition. We demonstrate a scaling of defect density and describe kink dynamics and stability. We further discuss the implementation of mass defects and electric fields as first steps toward controlled kink preparation and manipulation.

  7. AUTOMATED DEFECT CLASSIFICATION USING AN ARTIFICIAL NEURAL NETWORK

    SciTech Connect (OSTI)

    Chady, T.; Caryk, M. [Szczecin University of Technology, Department of Electrical Engineering (Poland); Piekarczyk, B. [Technic-Control, Szczecin (Poland)

    2009-03-03

    The automated defect classification algorithm based on artificial neural network with multilayer backpropagation structure was utilized. The selected features of flaws were used as input data. In order to train the neural network it is necessary to prepare learning data which is representative database of defects. Database preparation requires the following steps: image acquisition and pre-processing, image enhancement, defect detection and feature extraction. The real digital radiographs of welded parts of a ship were used for this purpose.

  8. Configuration of ripple domains and their topological defects...

    Office of Scientific and Technical Information (OSTI)

    their topological defects formed under local mechanical stress on hexagonal monolayer graphene Citation Details In-Document Search Title: Configuration of ripple domains and their...

  9. Improved, Defect-Free Electrode Materials - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Fuels Vehicles and Fuels Find More Like This Return to Search Improved, Defect-Free Electrode Materials Brookhaven National Laboratory Contact BNL About This Technology...

  10. Nonradiative coherent carrier captures and defect reaction at deep-level defects via phonon-kick mechanism

    SciTech Connect (OSTI)

    Wakita, Masaki; Suzuki, Kei; Shinozuka, Yuzo

    2014-02-21

    We simulated the time evolution of electron-lattice coupling mode, and a series of nonradiative carrier captures by a deep-level defect in a semiconductor. For lattice relaxation energy of the order of the band gap, a series of coherent (athermal) electron and hole captures by a defect is possible for high carrier densities, which results in an inflation in the induced lattice vibration, which in turn enhances a defect reaction.

  11. Energetics of Defects on Graphene through Fluorination

    SciTech Connect (OSTI)

    Xiao, Jie; Meduri, Praveen; Chen, Honghao; Wang, Zhiguo; Gao, Fei; Hu, Jian Z.; Feng, Ju; Hu, Mary Y.; Dai, Sheng; Brown, Suree; Adcock, Jamie L.; Deng, Zhiqun; Liu, Jun; Graff, Gordon L.; Aksay, Ilhan A.; Zhang, Jiguang

    2014-04-01

    In the present study, we used FGS[5] as the substrate and implemented low temperature (<=150 oC) direct fluorination on graphene sheets. The fluorine content has been modulated to investigate the formation mechanism of different functional groups such as C-F, CF2, O-CF2 and (C=O)F during the fluorination process. The detailed structure and chemical bonds were simulated theoretically and quantified experimentally by using density function theory (DFT) calculations and NMR techniques, respectively. The adjustable power/energy ratio from fluorinated graphene as cathode for primary lithium batteries is also discussed. From a combination of NMR spectroscopy and theoretical calculation, we conclude that the topological defects without oxygen containing groups provide most of the reactive sites to react with F. FGS also contain a small number of COOH groups which contribute for the fluorination reaction. Hydroxyl or epoxy groups contribute to another fraction of the reaction products.

  12. Mass transfer during drying of colloidal film beneath a patterned mask that contains a hexagonal array of holes

    E-Print Network [OSTI]

    Tarasevich, Yuri Yu

    2015-01-01

    We simulated an experiment in which a thin colloidal sessile droplet is allowed to dry out on a horizontal hydrophilic surface when a mask just above the droplet predominantly allows evaporation from the droplet free surface directly beneath the holes in the mask [Harris D J, Hu H, Conrad J C and Lewis J A 2007 \\textit{Phys. Rev. Lett.} \\textbf{98} 148301]. We considered one particular case when centre-to-centre spacing between the holes is much less than the drop diameter. In our model, advection, diffusion, and sedimentation were taken into account. FlexPDE was utilized to solve an advection-diffusion equation using the finite element method. The simulation demonstrated that the colloidal particles accumulate below the holes as the solvent evaporates. Diffusion can reduce this accumulation.

  13. Defect behavior of polycrystalline solar cell silicon

    SciTech Connect (OSTI)

    Schroder, D.K.; Park, S.H.; Hwang, I.G.; Mohr, J.B.; Hanly, M.P.

    1993-05-01

    The major objective of this study, conducted from October 1988 to September 1991, was to gain an understanding of the behavior of impurities in polycrystalline silicon and the influence of these impurities on solar cell efficiency. The authors studied edge-defined film-fed growth (EFG) and cast poly-Si materials and solar cells. With EFG Si they concentrated on chromium-doped materials and cells to determine the role of Cr on solar cell performance. Cast poly-Si samples were not deliberately contaminated. Samples were characterized by cell efficiency, current-voltage, deep-level transient spectroscopy (DLTS), surface photovoltage (SPV), open-circuit voltage decay, secondary ion mass spectrometry, and Fourier transform infrared spectroscopy measurements. They find that Cr forms Cr-B pairs with boron at room temperature and these pairs dissociate into Cr{sub i}{sup +} and B{sup {minus}} during anneals at 210{degrees}C for 10 min. Following the anneal, Cr-B pairs reform at room temperature with a time constant of 230 h. Chromium forms CrSi{sub 2} precipitates in heavily contaminated regions and they find evidence of CrSi{sub 2} gettering, but a lack of chromium segregation or precipitation to grain boundaries and dislocations. Cr-B pairs have well defined DLTS peaks. However, DLTS spectra of other defects are not well defined, giving broad peaks indicative of defects with a range of energy levels in the band gap. In some high-stress, low-efficiency cast poly-Si they detect SiC precipitates, but not in low-stress, high-efficiency samples. SPV measurements result in nonlinear SPV curves in some materials that are likely due to varying optical absorption coefficients due to locally varying stress in the material.

  14. Asymptotic Expansions of Defective Renewal Equations with Applications to Perturbed

    E-Print Network [OSTI]

    Blanchet, Jose H.

    Asymptotic Expansions of Defective Renewal Equations with Applications to Perturbed Risk Models. These expansions are applied to the analysis of Processor Sharing queues and perturbed risk models, and yield Introduction A defective renewal equation for a function ap (·) takes the form ap (t) = bp (t) + (1 - p) [0,t

  15. Fluctuations from edge defects in superconducting resonators A. Megrant,1

    E-Print Network [OSTI]

    Martinis, John M.

    Fluctuations from edge defects in superconducting resonators C. Neill,1 A. Megrant,1 R. Barends,1 August 2013) Superconducting resonators, used in astronomy and quantum computation, couple strongly to microscopic two-level defects. We monitor the microwave response of superconducting resonators and observe

  16. Simple intrinsic defects in InAs : numerical predictions.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2013-03-01

    This Report presents numerical tables summarizing properties of intrinsic defects in indium arsenide, InAs, as computed by density functional theory using semi-local density functionals, intended for use as reference tables for a defect physics package in device models.

  17. Measuring Point Defect Density in Individual Carbon Nanotubes Using

    E-Print Network [OSTI]

    Hitchcock, Adam P.

    Defects are known to reduce mechanical strength and Young modulus of the CNT and disrupt their electrical, and bending of the basal planes. Prolonged ex- posure shrinks MWCNTs and eventually re- moves their central not quantitative or show limited spatial resolution. In this paper, we demonstrate a new method to visualize defect

  18. Inflaton fluctuations in the presence of cosmological defects

    E-Print Network [OSTI]

    Hing-Tong Cho; Kin-Wang Ng; I-Chin Wang

    2014-10-06

    We study quantum fluctuations of a free massless scalar field during inflation in the presence of a point, line, or plane defect such as a black hole, cosmic string, or domain wall, using a perturbative expansion in powers of small defect parameters. We provide results for the scalar two-point correlation functions that show explicitly a small violation of translational invariance during inflation.

  19. Volunteering at Research and Cultural Collections From Egyptian shabti figures to nineteenth century medical waxes, from West African Masks to modern British

    E-Print Network [OSTI]

    Birmingham, University of

    century medical waxes, from West African Masks to modern British landscape paintings, the Research: Basic cleaning and conservation of objects e.g. cleaning and waxing outdoor sculpture Basic remedial

  20. Spin from defects in two-dimensional quantum field theory

    E-Print Network [OSTI]

    Sebastian Novak; Ingo Runkel

    2015-06-24

    We build two-dimensional quantum field theories on spin surfaces starting from theories on oriented surfaces with networks of topological defect lines and junctions. The construction uses a combinatorial description of the spin structure in terms of a triangulation equipped with extra data. The amplitude for the spin surfaces is defined to be the amplitude for the underlying oriented surface together with a defect network dual to the triangulation. Independence of the triangulation and of the other choices follows if the line defect and junctions are obtained from a Delta-separable Frobenius algebra with involutive Nakayama automorphism in the monoidal category of topological defects. For rational conformal field theory we can give a more explicit description of the defect category, and we work out two examples related to free fermions in detail: the Ising model and the so(n) WZW model at level 1.

  1. Spin from defects in two-dimensional quantum field theory

    E-Print Network [OSTI]

    Novak, Sebastian

    2015-01-01

    We build two-dimensional quantum field theories on spin surfaces starting from theories on oriented surfaces with networks of topological defect lines and junctions. The construction uses a combinatorial description of the spin structure in terms of a triangulation equipped with extra data. The amplitude for the spin surfaces is defined to be the amplitude for the underlying oriented surface together with a defect network dual to the triangulation. Independence of the triangulation and of the other choices follows if the line defect and junctions are obtained from a Delta-separable Frobenius algebra with involutive Nakayama automorphism in the monoidal category of topological defects. For rational conformal field theory we can give a more explicit description of the defect category, and we work out two examples related to free fermions in detail: the Ising model and the so(n) WZW model at level 1.

  2. Eddy Current Testing for Detecting Small Defects in Thin Films

    SciTech Connect (OSTI)

    Obeid, Simon; Tranjan, Farid M. [Electrical and Computer Engineering Department, UNCC (United States); Dogaru, Teodor [Albany Instruments, 426-O Barton Creek, Charlotte, NC 28262 (United States)

    2007-03-21

    Presented here is a technique of using Eddy Current based Giant Magneto-Resistance sensor (GMR) to detect surface and sub-layered minute defects in thin films. For surface crack detection, a measurement was performed on a copper metallization of 5-10 microns thick. It was done by scanning the GMR sensor on the surface of the wafer that had two scratches of 0.2 mm, and 2.5 mm in length respectively. In another experiment, metal coatings were deposited over the layers containing five defects with known lengths such that the defects were invisible from the surface. The limit of detection (resolution), in terms of defect size, of the GMR high-resolution Eddy Current probe was studied using this sample. Applications of Eddy Current testing include detecting defects in thin film metallic layers, and quality control of metallization layers on silicon wafers for integrated circuits manufacturing.

  3. Nonlinear beam deflection in photonic lattices with negative defects

    SciTech Connect (OSTI)

    Wang Jiandong [College of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Ye Zhuoyi; Lou Cibo [TEDA Applied Physical School, Nankai University, Tianjin 300457 (China); Miller, Alexandra; Zhang Peng [Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States); Hu Yi; Chen Zhigang [TEDA Applied Physical School, Nankai University, Tianjin 300457 (China); Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States); Yang Jianke [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401 (United States)

    2011-03-15

    We demonstrate both theoretically and experimentally that a nonlinear beam can be reflected by a negative defect in a photonic lattice if the incident angle is below a threshold value. Above this threshold angle, the beam simply passes through the defect. This phenomenon occurs in both one- and two-dimensional photonic lattices, and it provides a way to use the incident angle to control beam propagation in a lattice network. If the defect is absent or positive, no evident transition from reflection to transmission occurs. These nonlinear phenomena are also compared with linear nondiffracting-beam propagation in a photonic lattice with a defect, and both similarities and differences are observed. In addition, some important features in linear and nonlinear beam propagations are explained analytically by using a linear model with a delta-function defect.

  4. Pinning at template feature edges for step and flash imprint lithography Siddharth Chauhan, Frank Palmieri, Roger T. Bonnecaze,a

    E-Print Network [OSTI]

    SFIL see Fig. 1 is a low pressure molding process that uses a low-viscosity, UV-curable organosilicon . There are no repeating defects and the post array is almost fully populated. In a separate work, we have investi- gated

  5. Impact of polymer film thickness and cavity size on polymer flow during embossing : towards process design rules for nanoimprint lithography.

    SciTech Connect (OSTI)

    Schunk, Peter Randall; King, William P. (Georgia Institute of Technology, Atlanta, GA); Sun, Amy Cha-Tien; Rowland, Harry D.

    2006-08-01

    This paper presents continuum simulations of polymer flow during nanoimprint lithography (NIL). The simulations capture the underlying physics of polymer flow from the nanometer to millimeter length scale and examine geometry and thermophysical process quantities affecting cavity filling. Variations in embossing tool geometry and polymer film thickness during viscous flow distinguish different flow driving mechanisms. Three parameters can predict polymer deformation mode: cavity width to polymer thickness ratio, polymer supply ratio, and Capillary number. The ratio of cavity width to initial polymer film thickness determines vertically or laterally dominant deformation. The ratio of indenter width to residual film thickness measures polymer supply beneath the indenter which determines Stokes or squeeze flow. The local geometry ratios can predict a fill time based on laminar flow between plates, Stokes flow, or squeeze flow. Characteristic NIL capillary number based on geometry-dependent fill time distinguishes between capillary or viscous driven flows. The three parameters predict filling modes observed in published studies of NIL deformation over nanometer to millimeter length scales. The work seeks to establish process design rules for NIL and to provide tools for the rational design of NIL master templates, resist polymers, and process parameters.

  6. Integration of a 2D Periodic Nanopattern Into Thin Film Polycrystalline Silicon Solar Cells by Nanoimprint Lithography

    E-Print Network [OSTI]

    Abdo, Islam; Deckers, Jan; Depauw, Valérie; Tous, Loic; Van Gestel, Dries; Guindi, Rafik; Gordon, Ivan; Daif, Ounsi El

    2015-01-01

    The integration of two-dimensional (2D) periodic nanopattern defined by nanoimprint lithography and dry etching into aluminum induced crystallization (AIC) based polycrystalline silicon (Poly-Si) thin film solar cells is investigated experimentally. Compared to the unpatterned cell an increase of 6% in the light absorption has been achieved thanks to the nanopattern which, in turn, increased the short circuit current from 20.6 mA/cm2 to 23.8 mA/cm2. The efficiency, on the other hand, has limitedly increased from 6.4% to 6.7%. We show using the transfer length method (TLM) that the surface topography modification caused by the nanopattern has increased the sheet resistance of the antireflection coating (ARC) layer as well as the contact resistance between the ARC layer and the emitter front contacts. This, in turn, resulted in increased series resistance of the nanopatterned cell which has translated into a decreased fill factor, explaining the limited increase in efficiency.

  7. Cloud Detection with MODIS, Part I: Improvements in the MODIS Cloud Mask for Collection 5 *Richard A. Frey, Steven A. Ackerman, Yinghui Liu, Kathleen I. Strabala, Hong Zhang,

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Cloud Detection with MODIS, Part I: Improvements in the MODIS Cloud Mask for Collection 5 *Richard.frey@ssec.wisc.edu August 2007 #12;ABSTRACT Significant improvements have been made to the MODIS cloud mask (MOD35 and MYD35 to the 3.9-12 m and 11-12 m cloud tests. More non-MODIS ancillary input data has been added. Land and sea

  8. Operating Experience Level 3: Radcalc V4.1 Software Defect |...

    Office of Environmental Management (EM)

    Operating Experience Level 3: Radcalc V4.1 Software Defect Operating Experience Level 3: Radcalc V4.1 Software Defect September 6, 2011 OE-3 2011-01: Radcalc V4.1 Software Defect...

  9. Nematic cells with defect-patterned alignment layers

    E-Print Network [OSTI]

    Adam S. Backer; A. C. Callan-Jones; Robert A. Pelcovits

    2007-08-29

    Using Monte Carlo simulations of the Lebwohl--Lasher model we study the director ordering in a nematic cell where the top and bottom surfaces are patterned with a lattice of $\\pm 1$ point topological defects of lattice spacing $a$. We find that the nematic order depends crucially on the ratio of the height of the cell $H$ to $a$. When $H/a \\gtrsim 0.9$ the system is very well--ordered and the frustration induced by the lattice of defects is relieved by a network of half--integer defect lines which emerge from the point defects and hug the top and bottom surfaces of the cell. When $H/a \\lesssim 0.9$ the system is disordered and the half--integer defect lines thread through the cell joining point defects on the top and bottom surfaces. We present a simple physical argument in terms of the length of the defect lines to explain these results. To facilitate eventual comparison with experimental systems we also simulate optical textures and study the switching behavior in the presence of an electric field.

  10. Modeling and experimental characterization of stepped and v-shaped (311) defects in silicon

    SciTech Connect (OSTI)

    Marqués, Luis A. Aboy, María; Dudeck, Karleen J.; Botton, Gianluigi A.; Knights, Andrew P.; Gwilliam, Russell M.

    2014-04-14

    We propose an atomistic model to describe extended (311) defects in silicon. It is based on the combination of interstitial and bond defect chains. The model is able to accurately reproduce not only planar (311) defects but also defect structures that show steps, bends, or both. We use molecular dynamics techniques to show that these interstitial and bond defect chains spontaneously transform into extended (311) defects. Simulations are validated by comparing with precise experimental measurements on actual (311) defects. The excellent agreement between the simulated and experimentally derived structures, regarding individual atomic positions and shape of the distinct structural (311) defect units, provides strong evidence for the robustness of the proposed model.

  11. Accounting for Localized Defects in the Optoelectronic Design of Thin-Film Solar Cells

    E-Print Network [OSTI]

    Deceglie, Michael G.

    2014-01-01

    Accounting for Localized Defects in the OptoelectronicH solar cells. Explicitly accounting for local variations inthe importance of accounting for defect geometry, and that

  12. Probing graphene defects and estimating graphene quality with optical microscopy

    SciTech Connect (OSTI)

    Lai, Shen [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Center for Human Interface Nanotechnology (HINT), Suwon 440-746 (Korea, Republic of); Kyu Jang, Sung [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Jae Song, Young, E-mail: yjsong@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Department of Physics, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of); Lee, Sungjoo, E-mail: leesj@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Center for Human Interface Nanotechnology (HINT), Suwon 440-746 (Korea, Republic of); College of Information and Communication Engineering, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of)

    2014-01-27

    We report a simple and accurate method for detecting graphene defects that utilizes the mild, dry annealing of graphene/Cu films in air. In contrast to previously reported techniques, our simple approach with optical microscopy can determine the density and degree of dislocation of defects in a graphene film without inducing water-related damage or functionalization. Scanning electron microscopy, confocal Raman and atomic force microscopy, and X-ray photoelectron spectroscopy analysis were performed to demonstrate that our nondestructive approach to characterizing graphene defects with optimized thermal annealing provides rapid and comprehensive determinations of graphene quality.

  13. Heavy and Overweight Vehicle Defects Interim Report

    SciTech Connect (OSTI)

    Siekmann, Adam [ORNL; Capps, Gary J [ORNL

    2012-12-01

    The Federal Highway Administration (FHWA), along with the Federal Motor Carrier Safety Administration (FMCSA), has an interest in overweight commercial motor vehicles, how they affect infrastructure, and their impact on safety on the nation s highways. To assist both FHWA and FMCSA in obtaining more information related to this interest, data was collected and analyzed from two separate sources. A large scale nationwide data collection effort was facilitated by the Commercial Vehicle Safety Alliance as part of a special study on overweight vehicles and an additional, smaller set, of data was collected from the state of Tennessee which included a much more detailed set of data. Over a six-month period, 1,873 Level I inspections were performed in 18 different states that volunteered to be a part of this study. Of the 1,873 inspections, a vehicle out-of-service (OOS) violation was found on 44.79% of the vehicles, a rate significantly higher than the national OOS rate of 27.23%. The main cause of a vehicle being placed OOS was brake-related defects, with approximately 30% of all vehicles having an OOS brake violation. Only about 4% of vehicles had an OOS tire violation, and even fewer had suspension and wheel violations. Vehicle weight violations were most common on an axle group as opposed to a gross vehicle weight violation. About two thirds of the vehicles cited with a weight violation were overweight on an axle group with an average amount of weight over the legal limit of about 2,000 lbs. Data collection is scheduled to continue through January 2014, with more potentially more states volunteering to collect data. More detailed data collections similar to the Tennessee data collection will also be performed in multiple states.

  14. Defect reaction network in Si-doped InP : numerical predictions.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2013-10-01

    This Report characterizes the defects in the defect reaction network in silicon-doped, n-type InP deduced from first principles density functional theory. The reaction network is deduced by following exothermic defect reactions starting with the initially mobile interstitial defects reacting with common displacement damage defects in Si-doped InP until culminating in immobile reaction products. The defect reactions and reaction energies are tabulated, along with the properties of all the silicon-related defects in the reaction network. This Report serves to extend the results for intrinsic defects in SAND 2012-3313: %E2%80%9CSimple intrinsic defects in InP: Numerical predictions%E2%80%9D to include Si-containing simple defects likely to be present in a radiation-induced defect reaction sequence.

  15. Electron Beam Guides Engineering of Functional Defects | ornl...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Characterization Electron Beam Guides Engineering of Functional Defects May 20, 2015 Shown is a Z-contrast image of a vacancy-induced inversion domain (highlighted by the...

  16. 2005 May JOM 29 Casting DefectsOverview

    E-Print Network [OSTI]

    Beckermann, Christoph

    2005 May · JOM 29 Casting DefectsOverview Casting designs are generally based factors of safety, which leadtoincreasedcomponentweightsand inefficient use of materials. In castings in castings and determine their effect on performance. INTRODUCTION Designers are responsible for the per

  17. Re-entrant Lithium Local Environments and Defect Driven Electrochemist...

    Office of Scientific and Technical Information (OSTI)

    Lithium Local Environments and Defect Driven Electrochemistry of Li- and Mn-Rich Li-Ion Battery Cathodes Citation Details In-Document Search This content will become publicly...

  18. Defect specific maintenance of SG tubes -- How safe is it?

    SciTech Connect (OSTI)

    Cizelj, L.; Mavko, B.; Dvorsek, T. [Jozef Stefan Institute, Ljubljana (Slovenia)

    1997-02-01

    The efficiency of the defect specific plugging criterion for outside diameter stress corrosion cracking at tube support plates is assessed. The efficiency is defined by three parameters: (1) number of plugged tubes, (2) probability of steam generator tube rupture and (3) predicted accidental leak rate through the defects. A probabilistic model is proposed to quantify the probability of tube rupture, while procedures available in literature were used to define the accidental leak rates. The defect specific plugging criterion was then compared to the performance of traditional (45%) plugging criterion using realistic data from Krsko nuclear power plant. Advantages of the defect specific approach over the traditional one are clearly shown. Some hints on the optimization of safe life of steam generator are also given.

  19. Multiscale Defect Formation and Transport in Materials in Extreme Environments

    E-Print Network [OSTI]

    Seif, Dariush

    2013-01-01

    material symmetry (Iso, Anis) in the defect dipole tensors (through the [110]: Iso. P , Iso. ? (a) [110]: Anis. P ,Iso. ? [110]: Anis. P (1) , Anis. ? [100]: Iso. P , Iso. ? (

  20. Built-In Self Test (BIST) for Realistic Delay Defects 

    E-Print Network [OSTI]

    Tamilarasan, Karthik Prabhu

    2012-02-14

    Testing of delay defects is necessary in deep submicron (DSM) technologies. High coverage delay tests produced by automatic test pattern generation (ATPG) can be applied during wafer and package tests, but are difficult ...

  1. Modeling rough energy landscapes in defected condensed matter

    E-Print Network [OSTI]

    Monasterio Velásquez, Paul Rene

    2010-01-01

    This dissertation is a computational and theoretical investigation of the behavior of defected condensed matter and its evolution over long time scales. The thesis provides original contributions to the methodology used ...

  2. New Composite Silicon-Defect Graphene Anode Architecture

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A New Composite Silicon-Defect Graphene Anode Architecture for High Capacity, High-Rate Li-ion Batteries Xin Zhao, Cary Hayner, Mayfair Kung, and Harold Kung, Northwestern...

  3. Temperature Anisotropies in a Universe with Global Defects

    E-Print Network [OSTI]

    David Coulson

    1994-07-15

    We present a technique of calculating microwave anisotropies from global defects in a reionised universe. We concentrate on angular scales down to one degree where we expect the nongaussianity of the temperature anisotropy in these models to become apparent.

  4. Atomic Scale Details of Defect-Boundary Interactions 

    E-Print Network [OSTI]

    Chen, Di

    2014-12-18

    The study is aimed to understand atomic scale details of defect-boundary interactions, which are critical to develop radiation tolerant fuel cladding materials for harsher neutron environments. By means of molecular dynamics simulations, we...

  5. Design and optimization of a defect tolerant processor array 

    E-Print Network [OSTI]

    Lakkapragada, Bhavani S

    1995-01-01

    In this thesis we design and optimization of a defect tolerant MIMD processor array, for maximum performance per wafer area, targeted at applications that have a large number of operations per memory word, is described. The optimization includes...

  6. Influence of defects on thermal and mechanical properties of metals 

    E-Print Network [OSTI]

    Kamani, Sandeep Kumar

    2009-05-15

    ) and surface defects (grain boundary) using molecular dynamics simulations. Constant stress-constant temperature ensemble with atmospheric pressures is employed. Various properties like average volume, density, potential energy and total energy are obtained...

  7. Mitigation of substrate defects in reticles using multilayer buffer layers

    DOE Patents [OSTI]

    Mirkarimi, Paul B. (Sunol, CA); Bajt, Sasa (Livermore, CA); Stearns, Daniel G. (Los Altos, CA)

    2001-01-01

    A multilayer film is used as a buffer layer to minimize the size of defects on a reticle substrate prior to deposition of a reflective coating on the substrate. The multilayer buffer layer deposited intermediate the reticle substrate and the reflective coating produces a smoothing of small particles and other defects on the reticle substrate. The reduction in defect size is controlled by surface relaxation during the buffer layer growth process and by the degree of intermixing and volume contraction of the materials at the multilayer interfaces. The buffer layers are deposited at near-normal incidence via a low particulate ion beam sputtering process. The growth surface of the buffer layer may also be heated by a secondary ion source to increase the degree of intermixing and improve the mitigation of defects.

  8. Luminescence properties of defects in GaN

    SciTech Connect (OSTI)

    Reshchikov, Michael A.; Morkoc, Hadis [Department of Electrical Engineering and Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284 (United States)

    2005-03-15

    Gallium nitride (GaN) and its allied binaries InN and AIN as well as their ternary compounds have gained an unprecedented attention due to their wide-ranging applications encompassing green, blue, violet, and ultraviolet (UV) emitters and detectors (in photon ranges inaccessible by other semiconductors) and high-power amplifiers. However, even the best of the three binaries, GaN, contains many structural and point defects caused to a large extent by lattice and stacking mismatch with substrates. These defects notably affect the electrical and optical properties of the host material and can seriously degrade the performance and reliability of devices made based on these nitride semiconductors. Even though GaN broke the long-standing paradigm that high density of dislocations precludes acceptable device performance, point defects have taken the center stage as they exacerbate efforts to increase the efficiency of emitters, increase laser operation lifetime, and lead to anomalies in electronic devices. The point defects include native isolated defects (vacancies, interstitial, and antisites), intentional or unintentional impurities, as well as complexes involving different combinations of the isolated defects. Further improvements in device performance and longevity hinge on an in-depth understanding of point defects and their reduction. In this review a comprehensive and critical analysis of point defects in GaN, particularly their manifestation in luminescence, is presented. In addition to a comprehensive analysis of native point defects, the signatures of intentionally and unintentionally introduced impurities are addressed. The review discusses in detail the characteristics and the origin of the major luminescence bands including the ultraviolet, blue, green, yellow, and red bands in undoped GaN. The effects of important group-II impurities, such as Zn and Mg on the photoluminescence of GaN, are treated in detail. Similarly, but to a lesser extent, the effects of other impurities, such as C, Si, H, O, Be, Mn, Cd, etc., on the luminescence properties of GaN are also reviewed. Further, atypical luminescence lines which are tentatively attributed to the surface and structural defects are discussed. The effect of surfaces and surface preparation, particularly wet and dry etching, exposure to UV light in vacuum or controlled gas ambient, annealing, and ion implantation on the characteristics of the defect-related emissions is described.

  9. Rapid Coarsening of Ion Beam Ripple Patterns by Defect Annihilation

    SciTech Connect (OSTI)

    Hansen, Henri; Messlinger, Sebastian; Stoian, Georgiana [I. Physikalisches Institut, RWTH Aachen, 52056 Aachen (Germany); Redinger, Alex [I. Physikalisches Institut, RWTH Aachen, 52056 Aachen (Germany); II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany); Krug, Joachim [Institut fuer Theoretische Physik, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany); Michely, Thomas [II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany)

    2009-04-10

    Ripple patterns formed on Pt(111) through grazing incidence ion beam erosion coarsen rapidly. At and below 450 K coarsening of the patterns is athermal and kinetic, unrelated to diffusion and surface free energy. Similar to the situation for sand dunes, coarsening takes place through annihilation reactions of mobile defects in the pattern. The defect velocity derived on the basis of a simple model agrees quantitatively with the velocity of monatomic steps illuminated by the ion beam.

  10. Ultrasonic Tomography for Detecting and Locating Defects in Concrete Structures 

    E-Print Network [OSTI]

    White, Joshua

    2012-07-16

    ....................................................... 18 Figure 6 Typical C-scans for simulated defects in shotcrete slabs: Specimens D, E, I, and M ............................................................................................... 19 Figure 7 Clay lump slab construction... and shotcrete s labs. Figs. 5 and 6 delaminations, are shown in Figs. 5 and 6. The images in these figures are representative 19 19 Fig. 6. Typical C-scans for simulated defects in shotcrete slabs: Specimens D (top left), E (top right), I (bottom...

  11. Graphene materials having randomly distributed two-dimensional structural defects

    DOE Patents [OSTI]

    2013-10-08

    Graphene-based storage materials for high-power battery applications are provided. The storage materials are composed of vertical stacks of graphene sheets and have reduced resistance for Li ion transport. This reduced resistance is achieved by incorporating a random distribution of structural defects into the stacked graphene sheets, whereby the structural defects facilitate the diffusion of Li ions into the interior of the storage materials.

  12. Enhanced Software for Displaying Orthographic, Stereographic, Gnomic and Cylindrical Projections of the Sunpath Diagram and Shading Mask Protractor 

    E-Print Network [OSTI]

    Oh, K. W.; Haberl, J. S.; Degelman, L. O.

    2000-01-01

    -path diagram and shading mask protractor are well known graphic formats that have traditionally been used by architects and engineers to analyze whether or not a solar shading device will block direct sunlight on a given point in the plane of an exterior... (Schnieders et al. 1997), AWNSHADE (McCluney 1995), SOLAR-2 (Sheu 1986), SUNPATH (McCluney 1995), and SUNSPEC (McCluney 1995) programs. OPAQUE (Abouella and Milne 1990), developed by the Department of Architecture at UCLA, draws a detailed wall or roof...

  13. Crystal defect studies using x-ray diffuse scattering

    SciTech Connect (OSTI)

    Larson, B.C.

    1980-01-01

    Microscopic lattice defects such as point (single atom) defects, dislocation loops, and solute precipitates are characterized by local electronic density changes at the defect sites and by distortions of the lattice structure surrounding the defects. The effect of these interruptions of the crystal lattice on the scattering of x-rays is considered in this paper, and examples are presented of the use of the diffuse scattering to study the defects. X-ray studies of self-interstitials in electron irradiated aluminum and copper are discussed in terms of the identification of the interstitial configuration. Methods for detecting the onset of point defect aggregation into dislocation loops are considered and new techniques for the determination of separate size distributions for vacancy loops and interstitial loops are presented. Direct comparisons of dislocation loop measurements by x-rays with existing electron microscopy studies of dislocation loops indicate agreement for larger size loops, but x-ray measurements report higher concentrations in the smaller loop range. Methods for distinguishing between loops and three-dimensional precipitates are discussed and possibilities for detailed studies considered. A comparison of dislocation loop size distributions obtained from integral diffuse scattering measurements with those from TEM show a discrepancy in the smaller sizes similar to that described above.

  14. Implications of Permeation through Intrinsic Defects in Graphene on the Design of Defect-Tolerant Membranes for Gas Separation

    E-Print Network [OSTI]

    Sun, Chengzhen

    Gas transport through intrinsic defects and tears is a critical yet poorly understood phenomenon in graphene membranes for gas separation. We report that independent stacking of graphene layers on a porous support exponentially ...

  15. Ultrasonic generator and detector using an optical mask having a grating for launching a plurality of spatially distributed, time varying strain pulses in a sample

    DOE Patents [OSTI]

    Maris, Humphrey J. (Barrington, RI)

    2002-01-01

    A method and a system are disclosed for determining at least one characteristic of a sample that contains a substrate and at least one film disposed on or over a surface of the substrate. The method includes a first step of placing a mask over a free surface of the at least one film, where the mask has a top surface and a bottom surface that is placed adjacent to the free surface of the film. The bottom surface of the mask has formed therein or thereon a plurality of features for forming at least one grating. A next step directs optical pump pulses through the mask to the free surface of the film, where individual ones of the pump pulses are followed by at least one optical probe pulse. The pump pulses are spatially distributed by the grating for launching a plurality of spatially distributed, time varying strain pulses within the film, which cause a detectable change in optical constants of the film. A next step detects a reflected or a transmitted portion of the probe pulses, which are also spatially distributed by the grating. A next step measures a change in at least one characteristic of at least one of reflected or transmitted probe pulses due to the change in optical constants, and a further step determines the at least one characteristic of the sample from the measured change in the at least one characteristic of the probe pulses. An optical mask is also disclosed herein, and forms a part of these teachings.

  16. Ultrasonic generator and detector using an optical mask having a grating for launching a plurality of spatially distributed, time varying strain pulses in a sample

    DOE Patents [OSTI]

    Maris, Humphrey J. (Barrington, RI)

    2003-01-01

    A method and a system are disclosed for determining at least one characteristic of a sample that contains a substrate and at least one film disposed on or over a surface of the substrate. The method includes a first step of placing a mask over a free surface of the at least one film, where the mask has a top surface and a bottom surface that is placed adjacent to the free surface of the film. The bottom surface of the mask has formed therein or thereon a plurality of features for forming at least one grating. A next step directs optical pump pulses through the mask to the free surface of the film, where individual ones of the pump pulses are followed by at least one optical probe pulse. The pump pulses are spatially distributed by the grating for launching a plurality of spatially distributed, time varying strain pulses within the film, which cause a detectable change in optical constants of the film. A next step detects a reflected or a transmitted portion of the probe pulses, which are also spatially distributed by the grating. A next step measures a change in at least one characteristic of at least one of reflected or transmitted probe pulses due to the change in optical constants, and a further step determines the at least one characteristic of the sample from the measured change in the at least one characteristic of the probe pulses. An optical mask is also disclosed herein, and forms a part of these teachings.

  17. Defect studies in low-temperature-grown GaAs

    SciTech Connect (OSTI)

    Bliss, D.E.

    1992-11-01

    High content of excess As is incorporated in GaAs grown by low-temperature molecular-beam-epitaxy (LTMBE). The excess As exists primarily as As antisite defects AsGa and a lesser extent of gallium vacancies V[sub Ga]. The neutral AsGa-related defects were measured by infrared absorption at 1[mu]m. Gallium vacancies, V[sub Ga], was investigated by slow positron annihilation. Dependence of defect contents on doping was studied by Si and Be dopants. No free carriers are generated by n-type or p-type doping up to 10[sup 19] cm[sup [minus]3] Si or Be. Raman data indicate Be occupies Ga substitutional sites but Si atom is not substitutional. Si induces more As[sub Ga] in the layer. As As[sub Ga] increases, photoquenchable As[sub Ga] decreases. Fraction of photoquenchable defects correlates to defects within 3 nearest neighbor separations disrupting the metastability. Annealing reduces neutral As[sub Ga] content around 500C, similar to irradiation damaged and plastically deformed Ga[sub As], as opposed to bulk grown GaAs in which As[sub Ga]-related defects are stable up to 1100C. The lower temperature defect removal is due to V[sub Ga] enhanced diffusion of As[sub Ga] to As precipitates. The supersaturated V[sub GA] and also decreases during annealing. Annealing kinetics for As[sub Ga]-related defects gives 2.0 [plus minus] 0.3 eV and 1.5 [plus minus] 0.3 eV migration enthalpies for the As[sub Ga] and V[sub Ga]. This represents the difference between Ga and As atoms hopping into the vacancy. The non-photoquenchable As[sub Ga]-related defects anneal with an activation energy of 1.1 [plus minus] 0.3eV. Be acceptors can be activated by 800C annealing. Temperature difference between defect annealing and Be activation formation of As[sub Ga]-Be[sub Ga] pairs. Si donors can only be partially activated.

  18. Observation of lower to higher bandgap transition of one-dimensional defect modes

    E-Print Network [OSTI]

    Chen, Zhigang

    Observation of lower to higher bandgap transition of one-dimensional defect modes Xiaosheng Wang with a negative defect and observe linear bandgap guidance in such a defect. We show that a defect mode moves from and links 1. J. D. Joannopoulos, R. D. Meade, and J. N. Winn, Photonic Crystals: Molding the Flow of Light

  19. Mechanical properties of carbon nanotubes with vacancies and related defects M. Sammalkorpi,1,

    E-Print Network [OSTI]

    Nordlund, Kai

    mechanical characteris- tics. Likewise, defects may enhance the overall characteris- tics of bundles

  20. Use of relative code churn measures to predict system defect density

    E-Print Network [OSTI]

    Bae, Doo-Hwan

    Use of relative code churn measures to predict system defect density Nachiappan Nagappan and Thomas for potential defects Research goal · Create a set of relative code churn measures as early indicators of defects · Validate defect prediction power of the measures Code churn Measure of the amount of code change

  1. Systems and methods for forming defects on graphitic materials and curing radiation-damaged graphitic materials

    SciTech Connect (OSTI)

    Ryu, Sunmin; Brus, Louis E.; Steigerwald, Michael L.; Liu, Haitao

    2012-09-25

    Systems and methods are disclosed herein for forming defects on graphitic materials. The methods for forming defects include applying a radiation reactive material on a graphitic material, irradiating the applied radiation reactive material to produce a reactive species, and permitting the reactive species to react with the graphitic material to form defects. Additionally, disclosed are methods for removing defects on graphitic materials.

  2. Nanofabrication of sharp diamond tips by e-beam lithography and inductively coupled plasma reactive ion etching.

    SciTech Connect (OSTI)

    Moldovan, N.; Divan, R.; Zeng, H.; Carlisle, J. A.; Advanced Diamond Tech.

    2009-12-07

    Ultrasharp diamond tips make excellent atomic force microscopy probes, field emitters, and abrasive articles due to diamond's outstanding physical properties, i.e., hardness, low friction coefficient, low work function, and toughness. Sharp diamond tips are currently fabricated as individual tips or arrays by three principal methods: (1) focused ion beam milling and gluing onto a cantilever of individual diamond tips, (2) coating silicon tips with diamond films, or (3) molding diamond into grooves etched in a sacrificial substrate, bonding the sacrificial substrate to another substrate or electrodepositing of a handling chip, followed by dissolution of the sacrificial substrate. The first method is tedious and serial in nature but does produce very sharp tips, the second method results in tips whose radius is limited by the thickness of the diamond coating, while the third method involves a costly bonding and release process and difficulties in thoroughly filling the high aspect ratio apex of molding grooves with diamond at the nanoscale. To overcome the difficulties with these existing methods, this article reports on the feasibility of the fabrication of sharp diamond tips by direct etching of ultrananocrystalline diamond (UNCD{reg_sign}) as a starting and structural material. The UNCD is reactive ion etched using a cap-precursor-mask scheme. An optimized etching recipe demonstrates the formation of ultrasharp diamond tips ({approx} 10 nm tip radius) with etch rates of 650 nm/min.

  3. Maskless nanolithography and imaging with diffractive optical arrays

    E-Print Network [OSTI]

    Gil, Darío, 1975-

    2003-01-01

    Semiconductor lithography is at a crossroads. With mask set costs in excess of one million dollars, long mask turn-around times, and tools that are characterized by their inflexibility and skyrocketing costs, there is a ...

  4. Limitation of the Open-Circuit Voltage Due to Metastable Intrinsic Defects in Cu(In,Ga)Se2 and Strategies to Avoid These Defects: Preprint

    SciTech Connect (OSTI)

    Lany, S.; Zunger, A.

    2008-05-01

    This paper summarizes using first-principles defect theory to investigate the role of intrinsic point defects in the limitation of the open-circuit voltage (VOC) in Cu(In,Ga)Se2 solar cells.

  5. SU-E-T-603: Analysis of Optical Tracked Head Inter-Fraction Movements Within Masks to Access Intracranial Immobilization Techniques in Proton Therapy

    SciTech Connect (OSTI)

    Hsi, W; Zeidan, O

    2014-06-01

    Purpose: We present a quantitative methodology utilizing an optical tracking system for monitoring head inter-fraction movements within brain masks to assess the effectiveness of two intracranial immobilization techniques. Methods and Materials: A 3-point-tracking method was developed to measure the mask location for a treatment field at each fraction. Measured displacement of mask location to its location at first fraction is equivalent to the head movement within the mask. Head movements for each of treatment fields were measured over about 10 fractions at each patient for seven patients; five treated in supine and two treated in prone. The Q-fix Base-of-Skull head frame was used in supine while the CIVCO uni-frame baseplate was used in prone. Displacements of recoded couch position of each field post imaging at each fraction were extracted for those seven patients. Standard deviation (S.D.) of head movements and couch displacements was scored for statistical analysis. Results: The accuracy of 3PtTrack method was within 1.0 mm by phantom measurements. Patterns of head movement and couch displacement were similar for patients treated in either supine or prone. In superior-inferior direction, mean value of scored standard deviations over seven patients were 1.6 mm and 3.4 mm for the head movement and the couch displacement, respectively. The result indicated that the head movement combined with a loose fixation between the mask-to-head frame results large couch displacements for each patient, and also large variation between patients. However, the head movement is the main cause for the couch displacement with similar magnitude of around 1.0 mm in anterior-posterior and lateral directions. Conclusions: Optical-tracking methodology independently quantifying head movements could improve immobilization devices by correctly acting on causes for head motions within mask. A confidence in the quality of intracranial immobilization techniques could be more efficient by eliminating the need for frequent imaging.

  6. Predicting the Occurrence of Cosmetic Defects in Automotive Skin Panels

    SciTech Connect (OSTI)

    Hazra, S.; Williams, D.; Roy, R.; Aylmore, R.; Allen, M.; Hollingdale, D.

    2011-05-04

    The appearance of defects such as 'hollows' and 'shock lines' can affect the perceived quality and attractiveness of automotive skin panels. These defects are the result of the stamping process and appear as small, localized deviations from the intended styling of the panels. Despite their size, they become visually apparent after the application of paint and the perceived quality of a panel may become unacceptable. Considerable time is then dedicated to minimizing their occurrence through tool modifications. This paper will investigate the use of the wavelet transform as a tool to analyze physically measured panels. The transform has two key aspects. The first is its ability to distinguish small scale local defects from large scale styling curvature. The second is its ability to characterize the shape of a defect in terms of its wavelength and a 'correlation value'. The two features of the transform enable it to be used as a tool for locating and predicting the severity of defects. The paper will describe the transform and illustrate its application on test cases.

  7. Developmental defects in zebrafish for classification of EGF pathway inhibitors

    SciTech Connect (OSTI)

    Pruvot, Benoist; Curé, Yoann; Djiotsa, Joachim; Voncken, Audrey; Muller, Marc

    2014-01-15

    One of the major challenges when testing drug candidates targeted at a specific pathway in whole animals is the discrimination between specific effects and unwanted, off-target effects. Here we used the zebrafish to define several developmental defects caused by impairment of Egf signaling, a major pathway of interest in tumor biology. We inactivated Egf signaling by genetically blocking Egf expression or using specific inhibitors of the Egf receptor function. We show that the combined occurrence of defects in cartilage formation, disturbance of blood flow in the trunk and a decrease of myelin basic protein expression represent good indicators for impairment of Egf signaling. Finally, we present a classification of known tyrosine kinase inhibitors according to their specificity for the Egf pathway. In conclusion, we show that developmental indicators can help to discriminate between specific effects on the target pathway from off-target effects in molecularly targeted drug screening experiments in whole animal systems. - Highlights: • We analyze the functions of Egf signaling on zebrafish development. • Genetic blocking of Egf expression causes cartilage, myelin and circulatory defects. • Chemical inhibition of Egf receptor function causes similar defects. • Developmental defects can reveal the specificity of Egf pathway inhibitors.

  8. Structure, defects, and strain in silicon-silicon oxide interfaces

    SciTech Connect (OSTI)

    Kova?evi?, Goran Pivac, Branko

    2014-01-28

    The structure of the interfaces between silicon and silicon-oxide is responsible for proper functioning of MOSFET devices while defects in the interface can deteriorate this function and lead to their failure. In this paper we modeled this interface and characterized its defects and strain. MD simulations were used for reconstructing interfaces into a thermodynamically stable configuration. In all modeled interfaces, defects were found in the form of three-coordinated silicon atom, five coordinated silicon atom, threefold-coordinated oxygen atom, or displaced oxygen atom. Three-coordinated oxygen atom can be created if dangling bonds on silicon are close enough. The structure and stability of three-coordinated silicon atoms (P{sub b} defect) depend on the charge as well as on the electric field across the interface. The negatively charged P{sub b} defect is the most stable one, but the electric field resulting from the interface reduces that stability. Interfaces with large differences in periodic constants of silicon and silicon oxide can be stabilized by buckling of silicon layer. The mechanical stress resulted from the interface between silicon and silicon oxide is greater in the silicon oxide layer. Ab initio modeling of clusters representing silicon and silicon oxide shows about three time larger susceptibility to strain in silicon oxide than in silicon if exposed to the same deformation.

  9. Ultrasonic imaging system for in-process fabric defect detection

    DOE Patents [OSTI]

    Sheen, Shuh-Haw (Naperville, IL); Chien, Hual-Te (Naperville, IL); Lawrence, William P. (Downers Grove, IL); Raptis, Apostolos C. (Downers Grove, IL)

    1997-01-01

    An ultrasonic method and system are provided for monitoring a fabric to identify a defect. A plurality of ultrasonic transmitters generate ultrasonic waves relative to the fabric. An ultrasonic receiver means responsive to the generated ultrasonic waves from the transmitters receives ultrasonic waves coupled through the fabric and generates a signal. An integrated peak value of the generated signal is applied to a digital signal processor and is digitized. The digitized signal is processed to identify a defect in the fabric. The digitized signal processing includes a median value filtering step to filter out high frequency noise. Then a mean value and standard deviation of the median value filtered signal is calculated. The calculated mean value and standard deviation are compared with predetermined threshold values to identify a defect in the fabric.

  10. UNIVERSALITY OF PHASE TRANSITION DYNAMICS: TOPOLOGICAL DEFECTS FROM SYMMETRY BREAKING

    SciTech Connect (OSTI)

    Zurek, Wojciech H.; Del Campo, Adolfo

    2014-02-13

    In the course of a non-equilibrium continuous phase transition, the dynamics ceases to be adiabatic in the vicinity of the critical point as a result of the critical slowing down (the divergence of the relaxation time in the neighborhood of the critical point). This enforces a local choice of the broken symmetry and can lead to the formation of topological defects. The Kibble-Zurek mechanism (KZM) was developed to describe the associated nonequilibrium dynamics and to estimate the density of defects as a function of the quench rate through the transition. During recent years, several new experiments investigating formation of defects in phase transitions induced by a quench both in classical and quantum mechanical systems were carried out. At the same time, some established results were called into question. We review and analyze the Kibble-Zurek mechanism focusing in particular on this surge of activity, and suggest possible directions for further progress.

  11. Thermodynamic stability of oxygen point defects in cubic Zirconia

    E-Print Network [OSTI]

    Samanta, Amit; Li, Ju

    2010-01-01

    Zirconia (ZrO2) is an important material with technological applications which are affected by point defect physics. Ab-initio calculations are performed to understand the structural and electronic properties of oxygen vacancies and interstitials in different charge states in cubic zirconia. We find oxygen interstitials in cubic ZrO2 can have five different configurations - dumbbell, dumbbell, crowd-ion, octahedral, and distorted dumbbell. For a neutral and singly charged oxygen interstitial, the lowest energy configuration is the dumbbell, while for a doubly charged oxygen interstitial the octahedral site is energetically the most favorable. Both the oxygen interstitial and the oxygen vacancy are negative-U, so that the singly charged defects are unstable at any Fermi level. The thermodynamic stability of these defects are studied in terms of Fermi level, oxygen partial pressure and temperature. A method to determine the chemical potential of the system as a function of temperature and pressure is propo...

  12. On the defect induced gauge and Yukawa fields in graphene

    E-Print Network [OSTI]

    Corneliu Sochichiu

    2011-03-08

    We consider lattice deformations (both continuous and topological) in the hexagonal lattice Hubbard model in the tight binding approximation to graphene, involving operators with the range up to next-to-neighbor. In the low energy limit, we find that these deformations give rise to couplings of the electronic Dirac field to an external scalar (Yukawa) and gauge fields. The fields are expressed in terms of original defects. As a by-product we establish that the next-to-nearest order is the minimal range of deformations which produces the complete gauge and scalar fields. We consider an example of Stone--Wales defect, and find the associated gauge field.

  13. Non-perturbative embedding of local defects in crystalline materials

    E-Print Network [OSTI]

    Eric Cances; Amelie Deleurence; Mathieu Lewin

    2008-01-09

    We present a new variational model for computing the electronic first-order density matrix of a crystalline material in presence of a local defect. A natural way to obtain variational discretizations of this model is to expand the difference Q between the density matrix of the defective crystal and the density matrix of the perfect crystal, in a basis of precomputed maximally localized Wannier functions of the reference perfect crystal. This approach can be used within any semi-empirical or Density Functional Theory framework.

  14. Generalized Defect Energy in a Gradient Plasticity Framework

    E-Print Network [OSTI]

    Bayerschen, E

    2015-01-01

    A gradient plasticity model is presented that includes a generalized, power-law type defect energy depending on the gradient of an equivalent plastic strain. Numerical regularization for the case of vanishing gradients is employed in the finite element discretization of the theory. Three exemplary choices of the defect energy exponent are compared in finite element simulations of elastic-plastic tricrystals under tensile loading. The influence of the power-law exponent is discussed related to the distribution of gradients and in regard to size effects. In addition, an analytical solution is presented for the single slip case and allows to interpret the numerical findings.

  15. On the material geometry of continuously defective corrugated graphene sheets

    E-Print Network [OSTI]

    Andrzej Trzesowski

    2014-12-22

    Geometrical objects describing the material geometry of continuously defective graphene sheets are introduced and their compatibility conditions are formulated. Effective edge dislocations embedded in the Riemann-Cartan material space and defined by their scalar density and by local Burgers vectors, are considered. The case of secondary curvature-type defects created by this distribution of dislocations is analysed in terms of the material space. The variational geometry of the material space closely related with the existence of a characteristic length parameter is proposed. The formula which describes, in a reference temperature, the influence of dislocations on the material Riemannian metric, is given.

  16. Spatial adiabatic passage processes in sonic crystals with linear defects

    E-Print Network [OSTI]

    Ricard Menchon-Enrich; Jordi Mompart; Veronica Ahufinger

    2014-02-19

    We investigate spatial adiabatic passage processes for sound waves propagation in sonic crystals, consisting of steel cylinders embedded in a water host medium, that present two linear defects. This work constitutes an extension of the well-known quantum optical rapid adiabatic passage technique to the field of sound propagation. Several spatial adiabatic passage devices are proposed, by appropriately designing the geometry of the two linear defects along the propagation direction, to work as a coherent multifrequency adiabatic splitter, a phase difference analyzer and a coherent multifrequency adiabatic coupler. These devices are robust in front of fluctuations of the geometric parameter values.

  17. Comment on Scattering-Matrix Method for Determining Defect Modes 

    E-Print Network [OSTI]

    Allen, Roland E.

    1971-01-01

    VOLU ME 3, NUMBER 10 15 MAY 1971 Comment on the Scattering-Matrix Method for Determining Defect Modes* R. E. Allen Department of Physics, University of Texas, Austin, Texas 78712 (Received 25 June 1970) It is pointed out that the formulation... of the scattering-matrix method given by Achar and Barsch, which was proposed and used for calculating localized modes at surfaces and other planar defects, is based on an incorrect assumption. A formulation of the scattering-matrix method for calculating...

  18. Electronic and magnetic properties of zigzag silicene nanoribbons with Stone–Wales defects

    SciTech Connect (OSTI)

    Dong, Haixia; Fang, Dangqi; Gong, Baihua; Zhang, Yang; Zhang, Erhu; Zhang, Shengli

    2015-02-14

    The structural, electronic, and magnetic properties of zigzag silicene nanoribbons (ZSiNRs) with Stone–Wales (SW) defects were investigated using first-principles calculations. We found that two types of SW defects (named SW-? and SW-??) exist in ZSiNRs. The SW defect was found to be the most stable at the edge of the ZSiNR, independently of the defect orientation, even more stable than it is in an infinite silicene sheet. In addition, the ZSiNRs can transition from semiconductor to metal or half-metal by modifying the SW defect location and concentration. For the same defect concentration, the band structures influenced by the SW-? defect are more distinct than those influenced by the SW-?? when the SW defect is at the edge. The present study suggests the possibility of tuning the electronic properties of ZSiNRs using the SW defects and might motivate their potential application in nanoelectronics and spintronics.

  19. Solvent Immersion Imprint Lithography

    SciTech Connect (OSTI)

    Vasdekis, Andreas E.; Wilkins, Michael J.; Grate, Jay W.; Kelly, Ryan T.; Konopka, Allan; Xantheas, Sotiris S.; Chang, M. T.

    2014-06-21

    The mechanism of polymer disolution was explored for polymer microsystem prototyping, including microfluidics and optofluidics. Polymer films are immersed in a solvent, imprinted and finally brought into contact with a non-modified surface to permanently bond. The underlying polymer-solvent interactions were experimentally and theoretically investigated, and enabled rapid polymer microsystem prototyping. During imprinting, small molecule integration in the molded surfaces was feasible, a principle applied to oxygen sensing. Polystyrene (PS) was employed for microbiological studies at extreme environmental conditions. The thermophile anaerobe Clostridium Thermocellum was grown in PS pore-scale micromodels, revealing a double mean generation lifetime than under ideal culture conditions. Microsystem prototyping through directed polymer dissolution is simple and accessible, while simultaneous patterning, bonding, and surface/volume functionalization are possible in less than one minute.

  20. Lithography Trouble-Shooter

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    , or alternative coating techniques such as spray coating, roller coating, or dip coating are possible work, roller coating, or dip coating are reasonable alternatives for spin coating. Please contact us and Comet-Like Structures After Spin Coating? Possible reasons and work- arounds are listed in the section

  1. Advances in Lithography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News Publications Traditional Knowledge KiosksAboutHelp &AdvancedAdvancedExamples

  2. Climatic isotope signals in tree rings masked by air pollution: A case study conducted along the Mont Blanc Tunnel access road (Western Alps, Italy)

    E-Print Network [OSTI]

    Climatic isotope signals in tree rings masked by air pollution: A case study conducted along, Switzerland h i g h l i g h t s air pollution on the climatic signal recorded in the d13 C chronologies. Air pollution loads strongly influence the photosynthetic process.

  3. Nanofabrication of super-high-aspect-ratio structures in hydrogen silsesquioxane from direct-write e-beam lithography and hot development.

    SciTech Connect (OSTI)

    Ocola, L. E.; Tirumala, V. R.; Center for Nanoscale Materials; NIST

    2008-11-01

    Super-high-aspect-ratio structures (>10) in hydrogen silsesquioxane resist using direct write electron beam lithography at 100 kV and hot development and rinse are reported. Posts of 100 nm in width and 1.2 {micro}m tall have been successfully fabricated without the need of supercritical drying. Hot rinse solution with isopropyl alcohol has been used to reduce surface tension effects during drying. Dose absorption effects have been observed and modeled using known Monte Carlo models. These results indicate that for e-beam exposures of thick negative resists (>1 {micro}m), the bottom of the structures will have less cross-link density and therefore will be less stiff than the top. These results will have impact in the design of high-aspect-ratio structures that can be used in microelectromechanical system devices and high-aspect-ratio Fresnel zone plates.

  4. Defect Tolerance in VLSI Circuits: Techniques and Yield Analysis

    E-Print Network [OSTI]

    Koren, Israel

    severity grows proportionally with the size and density of the chip. Consequently, the development and use as the proportion of operational circuits to the total number of fabricated circuits. A yield of 100% is unlikely, due to various manufacturing defects that exist even under mature manufacturing conditions. Continuous

  5. Modeling of three dimensional defects in integrated circuits 

    E-Print Network [OSTI]

    Dani, Sameer Manohar

    1993-01-01

    properties that result from the interaction between the IC and the defect size in two coordinate spaces: x-y and z. The approach is a natural extension to the concept of critical areas, namely, the extraction of critical volumes. Through the course...

  6. 2005 May JOM 35 Casting DefectsOverview

    E-Print Network [OSTI]

    Haller, Gary L.

    2005 May · JOM 35 Casting DefectsOverview Superplastic forming (SPF) is intro- duced must fill the entire mold cavity and at the same time be cooled fast enough to avoidcrystallization.Thismakescasting of complex geometries (i.e., parts with thin sections and large aspect ratios) a challenging undertaking

  7. Automatic Detection of Defects in Riveted Lapjoints using Eddy Current

    E-Print Network [OSTI]

    Automatic Detection of Defects in Riveted Lap­joints using Eddy Current Fredrik Lingvall Tadeusz originating from rivet holes in a riveted lap­joint using eddy current (EC) inspection is presented consisted of median filtering, rotation and de­biasing of the eddy current pattern. The rotation

  8. Nature of Radiation-Induced Defects in Quartz

    E-Print Network [OSTI]

    Bu Wang; Yingtian Yu; Isabella Pignatelli; Gaurav N. Sant; Mathieu Bauchy

    2015-04-10

    Although quartz ($\\rm \\alpha$-form) is a mineral used in numerous applications wherein radiation exposure is an issue, the nature of the atomistic defects formed during radiation-induced damage have not been fully clarified. Especially, the extent of oxygen vacancy formation is still debated, which is an issue of primary importance as optical techniques based on charged oxygen vacancies have been utilized to assess the level of radiation damage in quartz. In this paper, molecular dynamics (MD) simulations are applied to study the effects of ballistic impacts on the atomic network of quartz. We show that the defects that are formed mainly consist of over-coordinated Si and O, as well as Si--O connectivity defects, e.g., small Si--O rings and edge-sharing Si tetrahedra. Oxygen vacancies, on the contrary, are found in relatively low abundance, suggesting that characterizations based on $E^{\\prime}$ centers do not adequately capture radiation-induced structural damage in quartz. Finally, we evaluate the dependence on the incident energy, of the amount of each type of the point defects formed, and quantify unambiguously the threshold displacement energies for both O and Si atoms. These results provide a comprehensive basis to assess the nature and extent of radiation damage in quartz.

  9. On the conservation of software defect CISM, University of Kingston

    E-Print Network [OSTI]

    Hatton, Les

    , T the temperature and R the gas constant is astonishingly accurate over a very wide range of pressures, then commonly used defect models for individual components directly im- ply that the distribution of component systems extremely accurately. For example, for a gas, PV = RT where P is the pressure, V the volume

  10. Fast non-iterative methods for defect identification

    E-Print Network [OSTI]

    Guzina, Bojan

    Fast non-iterative methods for defect identification Marc Bonnet -- Bojan B. Guzina -- Nicolas and topology by means of the concept of topological sensitivity. This approach leads to the fast computation is obtained by using fast multipole accelerated BEMs. Possibilities afforded by this approach are demon

  11. Graphene defect formation by extreme ultraviolet generated photoelectrons

    SciTech Connect (OSTI)

    Gao, A., E-mail: a.gao@utwente.nl; Lee, C. J.; Bijkerk, F. [FOM-Dutch Institute for Fundamental Energy Research, Edisonbaan 14, 3439 MN Nieuwegein, The Netherlands and XUV Optics Group, MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands)

    2014-08-07

    We have studied the effect of photoelectrons on defect formation in graphene during extreme ultraviolet (EUV) irradiation. Assuming the major role of these low energy electrons, we have mimicked the process by using low energy primary electrons. Graphene is irradiated by an electron beam with energy lower than 80?eV. After e-beam irradiation, it is found that the D peak, I(D), appears in the Raman spectrum, indicating defect formation in graphene. The evolution of I(D)/I(G) follows the amorphization trajectory with increasing irradiation dose, indicating that graphene goes through a transformation from microcrystalline to nanocrystalline and then further to amorphous carbon. Further, irradiation of graphene with increased water partial pressure does not significantly change the Raman spectra, which suggests that, in the extremely low energy range, e-beam induced chemical reactions between residual water and graphene are not the dominant mechanism driving defect formation in graphene. Single layer graphene, partially suspended over holes was irradiated with EUV radiation. By comparing with the Raman results from e-beam irradiation, it is concluded that the photoelectrons, especially those from the valence band, contribute to defect formation in graphene during irradiation.

  12. Simulations of Deep-Level Defects in Semiconductors

    E-Print Network [OSTI]

    Jones, Robert

    ( Z Y X v = 1 2f1 +2 +3 +4g;tx = 1 2f1 +2 ,3 ,4g 19 4 1999 4 #12;A. Resende AIMPRO Group ENDEASD. European Network on Defect Engineering of Advanced Semiconductor Devices ENDEASD #12;A. Resende AIMPRO

  13. Infrared photothermal radiometry of deep subsurface defects in semiconductor materials

    E-Print Network [OSTI]

    Mandelis, Andreas

    Infrared photothermal radiometry of deep subsurface defects in semiconductor materials M. E. Rodri sensitivity to the electronic transport properties of the laser photoexcited material.3 Using two information. INTRODUCTION The nondestructive, nonintrusive evaluation of semicon- ductor materials has been of common

  14. AutoODC: Automated Generation of Orthogonal Defect Classifications

    E-Print Network [OSTI]

    Ng, Vincent

    data are reported by users or developers during system development, operation and maintenance valuable in-process feedback to system development and maintenance. Conducting ODC classification classification and analysis of defect data bridge the gap between causal analysis and statistical quality control

  15. AutoODC: Automated Generation of Orthogonal Defect Classifications

    E-Print Network [OSTI]

    Ng, Vincent

    data are reported by users or developers during system development, operation and maintenance and analysis, provides valuable in­process feedback to system development and maintenance. Conducting ODC classification and analysis of defect data bridge the gap between causal analysis and statistical quality control

  16. An Empirical Comparison of Field Defect Modeling Methods

    E-Print Network [OSTI]

    operating system as judged by the Theil forecasting statistic (explained in section 4). We conjecture about Management, Measurement, Reliability, Experimentation, Defect modeling, empirical research, COTS, maintenance-based and metrics-based approach, as judged by the Theil forecasting statistic. We suggest possible conditions

  17. Strong NLS SolitonDefect Interactions # Roy H. Goodman #

    E-Print Network [OSTI]

    propose a mechanism of resonant energy transfer to a nonlinear standing wave mode supported by the defect and ex­ plored. The technique involves resonant transfer of energy from traveling waves (gap solitons Jersey Institute of Technology, Newark, NJ 07102 Philip J. Holmes Program in Applied and Computational

  18. Influence of defects distribution and specimen size on fracture initiation

    E-Print Network [OSTI]

    Krivtsov, Anton M.

    Influence of defects distribution and specimen size on fracture initiation Anton M. Krivtsov akrivtsov@bk.ru Abstract An analytical model for the scale dependence of the fracture initiation is suggested. The model is based on the idea that fracture is a stochastic process, for the bigger specimens

  19. The effect of defect introduction vs. load application sequencing on defect-induced stress distributions in steel samples

    E-Print Network [OSTI]

    Clapham, Lynann

    of Canada, Chalk River, Ontario, Canada K0J 1J0 Received 16 October 1998; received in revised form 20 May is needed to convert the MFL signal amplitudes into defect dimensions. When performing such calibration runs optimized. This is achieved by having th

  20. Inorganic-Organic Shape Memory Polymers and Foams for Bone Defect Repairs 

    E-Print Network [OSTI]

    Zhang, Dawei

    2013-04-16

    The ultimate goal of this research was to develop a “self-fitting” shape memory polymer (SMP) scaffold for the repair of craniomaxillofacial (CMF) bone defects. CMF defects may be caused by trauma, tumor removal or congenital abnormalities...

  1. Optimizing Test Pattern Generation Using Top-Off ATPG Methodology for Stuck–AT, Transition and Small Delay Defect Faults 

    E-Print Network [OSTI]

    Gill, Arjun

    2013-05-01

    of ATPG to not only include the conventional static defects but also to include test patterns for dynamic defects. The current industry practices consider test pattern generation for transition faults to screen dynamic defects. It has been observed...

  2. Defects in Ge and Si caused by 1 MeV Si+ implantation*

    E-Print Network [OSTI]

    Florida, University of

    Defects in Ge and Si caused by 1 MeV Si+ implantation* D. P. Hickeya Department of Materials defect formation and evolution in the 001 Ge and Si wafers implanted with 1 MeV Si+ and 40 keV Si dissolve at the projected range for nonamorphizing implants into Si. However, in Ge, no 311 defect

  3. Software Defect Data and Predictability for Testing Schedules Rattikorn Hewett & Aniruddha Kulkarni

    E-Print Network [OSTI]

    Stringfellow, Catherine V.

    Software Defect Data and Predictability for Testing Schedules Rattikorn Hewett & Aniruddha Kulkarni of resources. As software gets more complex, testing and fixing defects become difficult to schedule. This paper attempts to predict an estimated time for fixing software defects found during testing processes

  4. Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 20 Slide 1 Defect testing

    E-Print Network [OSTI]

    Scharff, Christelle

    ©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 20 Slide 1 Defect testing l Testing programs to establish the presence of system defects #12;©Ian Sommerville 2000 Software Sommerville 2000 Software Engineering, 6th edition. Chapter 20 Slide 3 Topics covered l Defect testing l

  5. DISSERTATION THE EFFECT OF TRAPPING DEFECTS ON CIGS SOLAR-CELL

    E-Print Network [OSTI]

    Sites, James R.

    DISSERTATION THE EFFECT OF TRAPPING DEFECTS ON CIGS SOLAR-CELL PERFORMANCE Submitted by Pamela K ENTITLED THE EFFECT OF TRAPPING DEFECTS ON CIGS SOLAR-CELL PERFORMANCE BE ACCEPTED AS FULFILLING IN PART RE OF DISSERTATION THE EFFECT OF TRAPPING DEFECTS ON CIGS SOLAR-CELL PERFORMANCE The relationship between basic solar-cell

  6. Robotic Tracking and Marking of Surface Shape Defects on Moving Automotive Panels

    E-Print Network [OSTI]

    Payeur, Pierre

    Robotic Tracking and Marking of Surface Shape Defects on Moving Automotive Panels Valentin Borsu defects for quality control in the automotive industry. In order to integrate a defects detection station. INTRODUCTION Quality control in the automotive industry is essential in order to ensure that the products meet

  7. Native defects in MBE-grown CdTe

    SciTech Connect (OSTI)

    Olender, Karolina; Wosinski, Tadeusz; Makosa, Andrzej; Tkaczyk, Zbigniew; Kolkovsky, Valery; Karczewski, Grzegorz

    2013-12-04

    Deep-level traps in both n- and p-type CdTe layers, grown by molecular-beam epitaxy on GaAs substrates, have been investigated by means of deep-level transient spectroscopy (DLTS). Four of the traps revealed in the DLTS spectra, which displayed exponential kinetics for capture of charge carriers into the trap states, have been assigned to native point defects: Cd interstitial, Cd vacancy, Te antisite defect and a complex formed of the Te antisite and Cd vacancy. Three further traps, displaying logarithmic capture kinetics, have been ascribed to electron states of treading dislocations generated at the mismatched interface with the substrate and propagated through the CdTe layer.

  8. Accessing defect dynamics using intense, nanosecond pulsed ion beams

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Persaud, A.; Barnard, J. J.; Guo, H.; Hosemann, P.; Lidia, S.; Minor, A. M.; Seidl, P. A.; Schenkel, T.

    2015-06-18

    Gaining in-situ access to relaxation dynamics of radiation induced defects will lead to a better understanding of materials and is important for the verification of theoretical models and simulations. We show preliminary results from experiments at the new Neutralized Drift Compression Experiment (NDCX-II) at Lawrence Berkeley National Laboratory that will enable in-situ access to defect dynamics through pump-probe experiments. Here, the unique capabilities of the NDCX-II accelerator to generate intense, nanosecond pulsed ion beams are utilized. Preliminary data of channeling experiments using lithium and potassium ions and silicon membranes are shown. We compare these data to simulation results using Crystalmore »Trim. Furthermore, we discuss the improvements to the accelerator to higher performance levels and the new diagnostics tools that are being incorporated.« less

  9. Elastic properties of vanadium pentoxide aggregates and topological defects

    E-Print Network [OSTI]

    L. V. Elnikova

    2008-11-07

    We study the aqueous solution of vanadium pentoxide by using topology methods. The experiments by Zocher, Kaznacheev, and Dogic exhibited, that in the sol phases of $V_2O_5-H_2O$, the tactoid droplets of $V_2O_5$ can coalesce. In the magnetic field, this effect is associated with a gauge field action, viz. we consider coalescence (in the topologically more convenient term, "junction") of droplets as annihilation of topological defects, concerning with the tactoid geometry. We have shown, that in the magnetic field, the tactoid junction is mainly caused by non-Abelian monopoles (vortons), whereas the Abelian defects almost do not annihilate. Taking into account this annihilation mechanism, the estimations of time-aging of the $V_2O_5-H_2O$ sols may be specified

  10. Doping-assisted defect control in compound semiconductors

    DOE Patents [OSTI]

    Specht, Petra; Weber, Eicke R.; Weatherford, Todd Russell

    2006-07-11

    The present invention relates to the production of thin film epilayers of III–V and other compounds with acceptor doping wherein the acceptor thermally stabilizes the epilayer, stabilize the naturally incorporated native defect population and therewith maintain the epilayer's beneficial properties upon annealing among other advantageous effects. In particular, balanced doping in which the acceptor concentration is similar to (but does not exceed) the antisite defects in the as-grown material is shown to be particularly advantageous in providing thermal stability, high resistivity and ultrashort trapping times. In particular, MBE growth of LT-GaAs epilayers with balanced Be doping is described in detail. The growth conditions greatly enhance the materials reproducibility (that is, the yield in processed devices). Such growth techniques can be transferred to other III–V materials if the growth conditions are accurately reproduced. Materials produced herein also demonstrate advantages in reproducibility, reliability and radiation hardening.

  11. Accessing defect dynamics using intense, nanosecond pulsed ion beams

    SciTech Connect (OSTI)

    Persaud, A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barnard, J. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Guo, H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hosemann, P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Lidia, S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Minor, A. M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Seidl, P. A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schenkel, T. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-01-01

    Gaining in-situ access to relaxation dynamics of radiation induced defects will lead to a better understanding of materials and is important for the verification of theoretical models and simulations. We show preliminary results from experiments at the new Neutralized Drift Compression Experiment (NDCX-II) at Lawrence Berkeley National Laboratory that will enable in-situ access to defect dynamics through pump-probe experiments. Here, the unique capabilities of the NDCX-II accelerator to generate intense, nanosecond pulsed ion beams are utilized. Preliminary data of channeling experiments using lithium and potassium ions and silicon membranes are shown. We compare these data to simulation results using Crystal Trim. Furthermore, we discuss the improvements to the accelerator to higher performance levels and the new diagnostics tools that are being incorporated.

  12. Defect density and dielectric constant in perovskite solar cells

    SciTech Connect (OSTI)

    Samiee, Mehran; Konduri, Siva; Abbas, Hisham A.; Joshi, Pranav; Zhang, Liang; Dalal, Vikram; Ganapathy, Balaji; Kottokkaran, Ranjith; Noack, Max; Kitahara, Andrew

    2014-10-13

    We report on measurement of dielectric constant, mid-gap defect density, Urbach energy of tail states in CH{sub 3}NH{sub 3}PbI{sub x}Cl{sub 1?x} perovskite solar cells. Midgap defect densities were estimated by measuring capacitance vs. frequency at different temperatures and show two peaks, one at 0.66?eV below the conduction band and one at 0.24?eV below the conduction band. The attempt to escape frequency is in the range of 2?×?10{sup 11}/s. Quantum efficiency data indicate a bandgap of 1.58?eV. Urbach energies of valence and conduction band are estimated to be ?16 and ?18?meV. Measurement of saturation capacitance indicates that the relative dielectric constant is ?18.

  13. CASTING DEFECT MODELING IN AN INTEGRATED COMPUTATIONAL MATERIALS ENGINEERING APPROACH

    SciTech Connect (OSTI)

    Sabau, Adrian S [ORNL

    2015-01-01

    To accelerate the introduction of new cast alloys, the simultaneous modeling and simulation of multiphysical phenomena needs to be considered in the design and optimization of mechanical properties of cast components. The required models related to casting defects, such as microporosity and hot tears, are reviewed. Three aluminum alloys are considered A356, 356 and 319. The data on calculated solidification shrinkage is presented and its effects on microporosity levels discussed. Examples are given for predicting microporosity defects and microstructure distribution for a plate casting. Models to predict fatigue life and yield stress are briefly highlighted here for the sake of completion and to illustrate how the length scales of the microstructure features as well as porosity defects are taken into account for modeling the mechanical properties. Thus, the data on casting defects, including microstructure features, is crucial for evaluating the final performance-related properties of the component. ACKNOWLEDGEMENTS This work was performed under a Cooperative Research and Development Agreement (CRADA) with the Nemak Inc., and Chrysler Co. for the project "High Performance Cast Aluminum Alloys for Next Generation Passenger Vehicle Engines. The author would also like to thank Amit Shyam for reviewing the paper and Andres Rodriguez of Nemak Inc. Research sponsored by the U. S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office, as part of the Propulsion Materials Program under contract DE-AC05-00OR22725 with UT-Battelle, LLC. Part of this research was conducted through the Oak Ridge National Laboratory's High Temperature Materials Laboratory User Program, which is sponsored by the U. S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Program.

  14. Extraordinary stiffness tunability through thermal expansion of nonlinear defect modes

    E-Print Network [OSTI]

    Marc Serra-Garcia; Joseph Lydon; Chiara Daraio

    2014-11-19

    Incremental stiffness characterizes the variation of a material's force response to a small deformation change. Typically materials have an incremental stiffness that is fixed and positive, but recent technologies, such as super-lenses, low frequency band gap materials and acoustic cloaks, are based on materials with zero, negative or extremely high incremental stiffness. So far, demonstrations of this behavior have been limited either to a narrow range of frequencies, temperatures, stiffness or to specific deformations. Here we demonstrate a mechanism to tune the static incremental stiffness that overcomes those limitations. This tunability is achieved by driving a nonlinear defect mode in a lattice. As in thermal expansion, the defect's vibration amplitude affects the force at the boundary, hence the lattice's stiffness. By using the high sensitivities of nonlinear systems near bifurcation points, we tune the magnitude of the incremental stiffness over a wide range: from positive, to zero, to arbitrarily negative values. The particular deformation where the incremental stiffness is modified can be arbitrarily selected varying the defect's driving frequency. We demonstrate this experimentally in a compressed array of spheres and propose a general theoretical model.

  15. Ab initio studies of niobium defects in uranium

    SciTech Connect (OSTI)

    Xiang, S; Huang, H; Hsiung, L

    2007-06-01

    Uranium (U), with the addition of small amount of niobium (Nb), is stainless. The Nb is fully miscible with the high temperature phase of U and tends to segregate upon cooling below 647 C. The starting point of segregation is the configuration of Nb substitutional or interstitial defects. Using density-functional-theory based ab initio calculations, the authors find that the formation energy of a single vacancy is 1.08 eV, that of Nb substitution is 0.59 eV, that of Nb interstitial at octahedral site is 1.58 eV, and that of Nb interstitial at tetrahedral site is 2.35 eV; all with reference to a reservoir of {gamma} phase U and pure Nb. The formation energy of Nb defects correlates with the local perturbation of electron distribution; higher formation energy to larger perturbation. Based on this study, Nb atoms thermodynamically prefer to occupy substitutional sites in {gamma} phase U, and they prefer to be in individual substitutional defects than clusters.

  16. Realizing the fusion rules of Ising anyons without lattice defects

    E-Print Network [OSTI]

    Ferreira, Miguel Jorge Bernabe; Teotonio-Sobrinho, Paulo

    2015-01-01

    Topologically ordered phases in two dimensions are characterized by their low energy excitations which are called anyons. These anyons are labeled by a set of anyon labels which can be braided and fused. These fusion and braiding properties can remain invariant under certain permutations of these anyon labels which generate an anyon symmetry group. In the example of the toric code this anyon symmetry manifests itself in the exchange of the charge, $e$ and flux, $m$ particles which is nothing but the electric-magnetic duality of the toric code model of Kitaev. However this is a global symmetry of the theory. It was shown to occur locally by the introduction of lattice defects which in turn induces a change in the toric code Hamiltonian along the defect. Here we introduce an exactly solvable model which achieves the local $e$-$m$ exchange without any modification to the lattice in the form of dislocations. However the Hamiltonian is still changed locally in what we call defect sites.These induce the permutation...

  17. Penta-hepta defect chaos in a model for rotating hexagonal convection

    E-Print Network [OSTI]

    Yuan-Nan Young; Hermann Riecke

    2002-09-19

    In a model for rotating non-Boussinesq convection with mean flow we identify a regime of spatio-temporal chaos that is based on a hexagonal planform and is sustained by the {\\it induced nucleation} of dislocations by penta-hepta defects. The probability distribution function for the number of defects deviates substantially from the usually observed Poisson-type distribution. It implies strong correlations between the defects inthe form of density-dependent creation and annihilation rates of defects. We extract these rates from the distribution function and also directly from the defect dynamics.

  18. Improving Cooling performance of the mechanical resonator with the two-level-system defects

    E-Print Network [OSTI]

    Tian Chen; Xiang-Bin Wang

    2014-06-03

    We study cooling performance of a realistic mechanical resonator containing defects. The normal cooling method through an optomechanical system does not work efficiently due to those defects. We show by employing periodical $\\sigma_z$ pulses, we can eliminate the interaction between defects and their surrounded heat baths up to the first order of time. Compared with the cooling performance of no $\\sigma_z$ pulses case, much better cooling results are obtained. Moreover, this pulse sequence has an ability to improve the cooling performance of the resonator with different defects energy gaps and different defects damping rates.

  19. Defect production during ion implantation of various A/sub III/B/sub V/ semiconductors

    SciTech Connect (OSTI)

    Wesch, W.; Wendler, E.; Goetz, G.; Kekelidse, N.P.

    1989-01-15

    The present paper gives a survey about the defect generation caused by ion implantation of GaAs, InAs, GaP, and InP. By combining Rutherford backscattering spectrometry, optical spectroscopy, and transmission electron microscopic methods, further information concerning the kinetics of the defect production as well as the type of defects created is obtained. Generally, the defect concentration in the region of implantation parameters investigated can be described by the energy density deposited into nuclear processes. Below critical values of the nuclear deposited energy density in GaAs weakly damaged layers containing point defects and point defect clusters are produced. With increasing nuclear deposited energy density an increasing number of amorphous zones is created due to manifold overlap of the initial defect clusters. The results indicate that in GaAs and InAs already at relatively low implantation temperatures, the amorphization occurs via homogeneous defect nucleation. The results obtained for GaP and InP, on the other hand, point at a remarkable contribution of heterogeneous defect nucleation already at room temperature, leading to amorphization at markedly lower nuclear deposited energy densities in spite of nearly identical values of the nuclear deposited energy. It is therefore concluded that defect recombination and annealing at room temperature is much less pronounced in the phosphides than in the arsenides.

  20. Enhanced optical power of GaN-based light-emitting diode with compound photonic crystals by multiple-exposure nanosphere-lens lithography

    SciTech Connect (OSTI)

    Zhang, Yonghui; Wei, Tongbo, E-mail: tbwei@semi.ac.cn; Xiong, Zhuo; Shang, Liang; Tian, Yingdong; Zhao, Yun; Zhou, Pengyu; Wang, Junxi; Li, Jinmin [Semiconductor Lighting Technology Research and Development Center, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2014-07-07

    The light-emitting diodes (LEDs) with single, twin, triple, and quadruple photonic crystals (PCs) on p-GaN are fabricated by multiple-exposure nanosphere-lens lithography (MENLL) process utilizing the focusing behavior of polystyrene spheres. Such a technique is easy and economical for use in fabricating compound nano-patterns. The optimized tilted angle is decided to be 26.6° through mathematic calculation to try to avoid the overlay of patterns. The results of scanning electron microscopy and simulations reveal that the pattern produced by MENLL is a combination of multiple ovals. Compared to planar-LED, the light output power of LEDs with single, twin, triple, and quadruple PCs is increased by 14.78%, 36.03%, 53.68%, and 44.85% under a drive current 350?mA, respectively. Furthermore, all PC-structures result in no degradation of the electrical properties. The stimulated results indicate that the highest light extraction efficiency of LED with the clover-shape triple PC is due to the largest scattering effect on propagation of light from GaN into air.

  1. Blade reliability collaborative : collection of defect, damage and repair data.

    SciTech Connect (OSTI)

    Ashwill, Thomas D.; Ogilvie, Alistair B.; Paquette, Joshua A.

    2013-04-01

    The Blade Reliability Collaborative (BRC) was started by the Wind Energy Technologies Department of Sandia National Laboratories and DOE in 2010 with the goal of gaining insight into planned and unplanned O&M issues associated with wind turbine blades. A significant part of BRC is the Blade Defect, Damage and Repair Survey task, which will gather data from blade manufacturers, service companies, operators and prior studies to determine details about the largest sources of blade unreliability. This report summarizes the initial findings from this work.

  2. Highly defective oxides as sinter resistant thermal barrier coating

    DOE Patents [OSTI]

    Subramanian, Ramesh

    2005-08-16

    A thermal barrier coating material formed of a highly defective cubic matrix structure having a concentration of a stabilizer sufficiently high that the oxygen vacancies created by the stabilizer interact within the matrix to form multi-vacancies, thereby improving the sintering resistance of the material. The concentration of stabilizer within the cubic matrix structure is greater than that concentration of stabilizer necessary to give the matrix a peak ionic conductivity value. The concentration of stabilizer may be at least 30 wt. %. Embodiments include a cubic matrix of zirconia stabilized by at least 30-50 wt. % yttria, and a cubic matrix of hafnia stabilized by at least 30-50 wt. % gadolinia.

  3. Large effect of polydispersity on defect concentrations in colloidal crystals

    E-Print Network [OSTI]

    Sander Pronk; Daan Frenkel

    2004-02-03

    We compute the equilibrium concentration of stacking faults and point defects in polydisperse hard-sphere crystals. We find that, while the concentration of stacking faults remains similar to that of monodisperse hard sphere crystals, the concentration of vacancies decreases by about a factor two. Most strikingly, the concentration of interstitials in the maximally polydisperse crystal may be some six orders of magnitude larger than in a monodisperse crystal. We show that this dramatic increase in interstitial concentration is due to the increased probability of finding small particles and that the small-particle tail of the particle size distribution is crucial for the interstitial concentration in a colloidal crystal.

  4. Sandia Energy - Research Challenge 4: Defect-Carrier Interactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid youOxygenLaboratory Fellows JerryPredictive4: Defect-Carrier

  5. Center for Defect Physics in Structural Materials - CDP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaonforsupernovae modelsearch this siteSearchACenter for Defect

  6. Defective graphene as promising anode material for Na-ion battery and Ca-ion battery

    E-Print Network [OSTI]

    Datta, Dibakar; Shenoy, Vivek B

    2013-01-01

    We have investigated adsorption of Na and Ca on graphene with divacancy (DV) and Stone-Wales (SW) defect. Our results show that adsorption is not possible on pristine graphene. However, their adsorption on defective sheet is energetically favorable. The enhanced adsorption can be attributed to the increased charge transfer between adatoms and underlying defective sheet. With the increase in defect density until certain possible limit, maximum percentage of adsorption also increases giving higher battery capacity. For maximum possible DV defect, we can achieve maximum capacity of 1459 mAh/g for Na-ion batteries (NIBs) and 2900 mAh/g for Ca-ion batteries (CIBs). For graphene full of SW defect, we find the maximum capacity of NIBs and CIBs is around 1071 mAh/g and 2142 mAh/g respectively. Our results will help create better anode materials with much higher capacity and better cycling performance for NIBs and CIBs.

  7. Nematic ordering of topological defects in active liquid crystals

    E-Print Network [OSTI]

    Anand U. Oza; Jörn Dunkel

    2015-07-15

    Identifying the ordering principles of intracellular matter is key to understanding the physics of microbiological systems. Recent experiments show that ATP-driven microtubule-kinesin bundles can form non-equilibrium networks of liquid-crystalline order when trapped in an oil-water interface near a solid boundary. At high densities, the bundles realize a 2D active nematic phase characterized by spontaneous creation and annihilation of topological defects, reminiscent of particle-pair production processes in quantum systems. This remarkable discovery sparked considerable theoretical interest, yet a satisfactory mathematical description has remained elusive, primarily for the following two reasons. First, prevailing multi-component theories feature a large number of unknown parameters that make quantitative comparison with experiment infeasible. Second, the currently favored hydrodynamic models assume divergence-free 2D interfacial flow, thereby promoting turbulent pattern formation through upward cascades. Such cascades are unlikely to occur in experiments, where interface and bulk fluid can continuously exchange matter. Here, we propose a compact alternative continuum theory for dense active liquid crystals by merging ideas from the Landau-de Gennes and Swift-Hohenberg theories. The resulting fourth-order model agrees quantitatively with experimental data, correctly predicts a regime of long-range nematic alignment of defects, and manifests an analogy with a generalized Gross-Pitaevskii quantum theory. Generally, our results suggest that universal ordering principles may govern a wide range of active materials.

  8. Defect structure of ultrafine MgB{sub 2} nanoparticles

    SciTech Connect (OSTI)

    Bateni, Ali; Somer, Mehmet E-mail: msomer@ku.edu.tr; Repp, Sergej; Erdem, Emre E-mail: msomer@ku.edu.tr; Thomann, Ralf; Acar, Selçuk

    2014-11-17

    Defect structure of MgB{sub 2} bulk and ultrafine particles, synthesized by solid state reaction route, have been investigated mainly by the aid of X-band electron paramagnetic resonance spectrometer. Two different amorphous Boron (B) precursors were used for the synthesis of MgB{sub 2}, namely, boron 95 (purity 95%–97%, <1.5??m) and nanoboron (purity >98.5%, <250?nm), which revealed bulk and nanosized MgB{sub 2}, respectively. Scanning and transmission electron microscopy analysis demonstrate uniform and ultrafine morphology for nanosized MgB{sub 2} in comparison with bulk MgB{sub 2}. Powder X-ray diffraction data show that the concentration of the by-product MgO is significantly reduced when nanoboron is employed as precursor. It is observed that a significant average particle size reduction for MgB{sub 2} can be achieved only by using B particles of micron or nano size. The origin and the role of defect centers were also investigated and the results proved that at nanoscale MgB{sub 2} material contains Mg vacancies. Such vacancies influence the connectivity and the conductivity properties which are crucial for the superconductivity applications.

  9. Subsurface Defect Detection in Metals with Pulsed Eddy Current

    SciTech Connect (OSTI)

    Plotnikov, Yuri A. [GE Global Research Center, One Research Circle, Niskayuna, NY 12309-1135 (United States); Bantz, Walter J. [GE Aircraft Engines M and QTD, 10270 St. Rita Lane, Cincinnati, OH 45215 (United States)

    2005-04-09

    The eddy current (EC) method is traditionally used for open surface crack detection in metallic components. Subsurface voids in bulk metals can also be detected by the eddy current devices. Taking into consideration the skin effect in conductive materials, a lower frequency of electromagnetic excitation is used for a deeper penetration. A set of special specimens was designed and fabricated to investigate sensitivity to subsurface voids. Typically, flat bottom holes (FBHs) are used for subsurface defect simulation. This approach is not very representative of real defects for eddy current inspection because the FBH depth extends to the bottom of the specimen. Two-layer specimens with finite depth FBHs were fabricated and scanned with conventional EC of variable frequency. Sensitivity and spatial resolution of EC diminish with flaw depth. The pulsed EC approach was applied for flaw detection at variable distance under the surface. The transient response from multi-layer model was derived and compared to experiments. The multi-frequency nature of pulsed excitation provides effective coverage of a thick layer of material in one pass. Challenging aspects of subsurface flaw detection and visualization using the EC technique are discussed.

  10. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    SciTech Connect (OSTI)

    Gasenzer, Thomas; McLerran, Larry; Pawlowski, Jan M.; Sexty, Dénes

    2014-07-28

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixed point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang–Mills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.

  11. Chiral asymmetry in propagation of soliton defects in crystalline backgrounds

    E-Print Network [OSTI]

    Adrian Arancibia; Mikhail S. Plyushchay

    2015-08-03

    By applying Darboux-Crum transformations to the Lax pair formulation of the Korteweg-de Vries (KdV) equation, we construct new sets of multi-soliton solutions to it as well as to the modified Korteweg-de Vries (mKdV) equation. The obtained solutions exhibit a chiral asymmetry in propagation of different types defects in crystalline backgrounds. We show that the KdV solitons of pulse and compression modulation types, which support bound states in semi-infinite and finite forbidden bands in the spectrum of the perturbed quantum one-gap Lame system, propagate in opposite directions with respect to the asymptotically periodic background. A similar but more complicated picture also appears for the multi-kink-antikink mKdV solitons that propagate with a privileged direction over topologically trivial or topologically nontrivial crystalline background in dependence on position of energy levels of the trapped bound states in spectral gaps of the associated Dirac system. Exotic N=4 nonlinear supersymmetric structure incorporating Lax-Novikov integrals of a pair of perturbed Lame systems is shown to underlie the Miura-Darboux-Crum construction. It unifies the KdV and mKdV solutions, detects the defects and distinguishes their types, and identifies the types of crystalline backgrounds.

  12. Dark Matter with Topological Defects in the Inert Doublet Model

    E-Print Network [OSTI]

    Mark Hindmarsh; Russell Kirk; Jose Miguel No; Stephen M. West

    2015-07-29

    We examine the production of dark matter by decaying topological defects in the high mass region $m_{\\mathrm{DM}} \\gg m_W$ of the Inert Doublet Model, extended with an extra U(1) gauge symmetry. The density of dark matter states (the neutral Higgs states of the inert doublet) is determined by the interplay of the freeze-out mechanism and the additional production of dark matter states from the decays of topological defects, in this case cosmic strings. These decays increase the predicted relic abundance compared to the standard freeze-out only case, and as a consequence the viable parameter space of the Inert Doublet Model can be widened substantially. In particular, for a given dark matter annihilation rate lower dark matter masses become viable. We investigate the allowed mass range taking into account constraints on the energy injection rate from the diffuse $\\gamma$-ray background and Big Bang Nucleosynthesis, together with constraints on the dark matter properties coming from direct and indirect detection limits. For the Inert Doublet Model high-mass region, an inert Higgs mass as low as $\\sim 200$ GeV is permitted. There is also an upper limit on string mass per unit length, and hence the symmetry breaking scale, from the relic abundance in this scenario. Depending on assumptions made about the string decays, the limits are in the range $10^{12}$ GeV to $10^{13}$ GeV.

  13. Taming Supersymmetric Defects in 3d-3d Correspondence

    E-Print Network [OSTI]

    Gang, Dongmin; Romo, Mauricio; Yamazaki, Masahito

    2015-01-01

    We study knots in 3d Chern-Simons theory with complex gauge group $SL(N,\\mathbb{C})$, in the context of its relation with 3d $\\mathcal{N}=2$ theory (the so-called 3d-3d correspondence). The defect has either co-dimension 2 or co-dimension 4 inside the 6d $(2,0)$ theory, which is compactified on a 3-manifold $\\hat{M}$. We identify such defects in various corners of the 3d-3d correspondence, namely in 3d $SL(N,\\mathbb{C})$ Chern-Simons theory, in 3d $\\mathcal{N}=2$ theory, in 5d $\\mathcal{N}=2$ super Yang-Mills theory, and in the M-theory holographic dual. We can make quantitative checks of the 3d-3d correspondence by computing partition functions at each of these theories. This Letter is a companion to a longer paper, which contains more details and more results.

  14. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    SciTech Connect (OSTI)

    Gasenzer, Thomas [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI); McLerran, Larry [Brookhaven National Lab. (BNL), Upton, NY (United States). RIKEN Research Center and Physics Dept.; China Central Normal Univ., Wuhan (China). Physics Dept.; Pawlowski, Jan M. [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI); Sexty, Dénes [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI)

    2014-10-01

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixed point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang–Mills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.

  15. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gasenzer, Thomas; McLerran, Larry; Pawlowski, Jan M.; Sexty, Dénes

    2014-07-28

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixedmore »point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang–Mills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.« less

  16. Diffusion Coefficients in a Lamellar Lyotropic Phase: Evidence for Defects Connecting the Surfactant Structure

    E-Print Network [OSTI]

    Doru Constantin; Patrick Oswald

    2015-04-09

    We measure diffusion coefficients in the lamellar phase of the nonionic binary system C$_{12}$EO$_6$/H$_2$O using fluorescence recovery after photobleaching. The diffusion coefficient across the lamellae shows an abrupt increase upon approaching the lamellar-isotropic phase transition. We interpret this feature in terms of defects connecting the surfactant structure. An estimation of the defect density and of the variation in defect energy close to the transition is given in terms of a simple model.

  17. Transport-reaction model for defect and carrier behavior within displacement cascades in gallium arsenide

    SciTech Connect (OSTI)

    Wampler, William R.; Myers, Samuel M.

    2014-02-01

    A model is presented for recombination of charge carriers at displacement damage in gallium arsenide, which includes clustering of the defects in atomic displacement cascades produced by neutron or ion irradiation. The carrier recombination model is based on an atomistic description of capture and emission of carriers by the defects with time evolution resulting from the migration and reaction of the defects. The physics and equations on which the model is based are presented, along with details of the numerical methods used for their solution. The model uses a continuum description of diffusion, field-drift and reaction of carriers and defects within a representative spherically symmetric cluster. The initial radial defect profiles within the cluster were chosen through pair-correlation-function analysis of the spatial distribution of defects obtained from the binary-collision code MARLOWE, using recoil energies for fission neutrons. Charging of the defects can produce high electric fields within the cluster which may influence transport and reaction of carriers and defects, and which may enhance carrier recombination through band-to-trap tunneling. Properties of the defects are discussed and values for their parameters are given, many of which were obtained from density functional theory. The model provides a basis for predicting the transient response of III-V heterojunction bipolar transistors to pulsed neutron irradiation.

  18. 2012 DEFECTS IN SEMICONDUCTORS GORDON RESEARCH CONFERENCE, AUGUST 12-17, 2012

    SciTech Connect (OSTI)

    GLASER, EVAN

    2012-08-17

    The meeting shall strive to develop and further the fundamental understanding of defects and their roles in the structural, electronic, optical, and magnetic properties of bulk, thin film, and nanoscale semiconductors and device structures. Point and extended defects will be addressed in a broad range of electronic materials of particular current interest, including wide bandgap semiconductors, metal-oxides, carbon-based semiconductors (e.g., diamond, graphene, etc.), organic semiconductors, photovoltaic/solar cell materials, and others of similar interest. This interest includes novel defect detection/imaging techniques and advanced defect computational methods.

  19. A transmission matrix for a fused pair of integrable defects in the sine-Gordon model

    E-Print Network [OSTI]

    E. Corrigan; C. Zambon

    2010-06-04

    Within the quantum sine-Gordon model a transmission matrix describing the scattering of a soliton with a fused pair of integrable defects is proposed. The result is consistent with the classical picture of scattering and highlights the differences between two defects located at separated points and two defects fused at the same point. Moreover, the analysis reveals how, for certain choices of parameters, both the soliton-soliton and the lightest-breather-soliton S-matrices of the sine-Gordon model are embedded within the transmission matrix, supporting an interpretation in which defects may be regarded as soliton constituents.

  20. American Institute of Aeronautics and Astronautics Effects of Defects: Part A -Development of a Protocol for

    E-Print Network [OSTI]

    American Institute of Aeronautics and Astronautics 1 Effects of Defects: Part A - Development;American Institute of Aeronautics and Astronautics 2 Introduction he size, weight, shape and economic

  1. Nematic ordering of topological defects in active liquid crystals

    E-Print Network [OSTI]

    Oza, Anand U

    2015-01-01

    Identifying the ordering principles of intracellular matter is key to understanding the physics of microbiological systems. Recent experiments show that ATP-driven microtubule-kinesin bundles can form non-equilibrium networks of liquid-crystalline order when trapped in an oil-water interface near a solid boundary. At high densities, the bundles realize a 2D active nematic phase characterized by spontaneous creation and annihilation of topological defects, reminiscent of particle-pair production processes in quantum systems. This remarkable discovery sparked considerable theoretical interest, yet a satisfactory mathematical description has remained elusive, primarily for the following two reasons. First, prevailing multi-component theories feature a large number of unknown parameters that make quantitative comparison with experiment infeasible. Second, the currently favored hydrodynamic models assume divergence-free 2D interfacial flow, thereby promoting turbulent pattern formation through upward cascades. Suc...

  2. Electrodes mitigating effects of defects in organic electronic devices

    DOE Patents [OSTI]

    Heller, Christian Maria Anton (Albany, NY)

    2008-05-06

    A compound electrode for organic electronic devices comprises a thin first layer of a first electrically conducting material and a second electrically conducting material disposed on the first layer. In one embodiment, the second electrically conducting material is formed into a plurality of elongated members. In another embodiment, the second material is formed into a second layer. The elongated members or the second layer has a thickness greater than that of the first layer. The second layer is separated from the first layer by a conducting material having conductivity less than at least the material of the first layer. The compound electrode is capable of mitigating adverse effects of defects, such as short circuits, in the construction of the organic electronic devices, and can be included in light-emitting or photovoltaic devices.

  3. Periodic Schrödinger operators with local defects and spectral pollution

    E-Print Network [OSTI]

    Eric Cancès; Virginie Ehrlacher; Yvon Maday

    2011-11-16

    This article deals with the numerical calculation of eigenvalues of perturbed periodic Schr\\"odinger operators located in spectral gaps. Such operators are encountered in the modeling of the electronic structure of crystals with local defects, and of photonic crystals. The usual finite element Galerkin approximation is known to give rise to spectral pollution. In this article, we give a precise description of the corresponding spurious states. We then prove that the supercell model does not produce spectral pollution. Lastly, we extend results by Lewin and S\\'er\\'e on some no-pollution criteria. In particular, we prove that using approximate spectral projectors enables one to eliminate spectral pollution in a given spectral gap of the reference periodic Sch\\"odinger operator.

  4. Nonlocal competition and logistic growth: patterns, defects and fronts

    E-Print Network [OSTI]

    Yosef E. Maruvka; Nadav M. Shnerb

    2005-06-22

    Logistic growth of diffusing reactants on spatial domains with long range competition is studied. The bifurcations cascade involved in the transition from the homogenous state to a spatially modulated stable solution is presented, and a distinction is made between a modulated phase, dominated by single or few wavenumbers, and the spiky phase, where localized colonies are separated by depleted region. The characteristic defects in the periodic structure are presented for each phase, together with the invasion dynamics in case of local initiation. It is shown that the basic length scale that controls the bifurcation is the width of the Fisher front, and that the total population grows as this width decreases. A mix of analytic results and extensive numerical simulations yields a comprehensive examination of the possible phases for logistic growth in the presence of nonlocal competition.

  5. Ion beam collimating grid to reduce added defects

    DOE Patents [OSTI]

    Lindquist, Walter B. (Oakland, CA); Kearney, Patrick A. (Livermore, CA)

    2003-01-01

    A collimating grid for an ion source located after the exit grid. The collimating grid collimates the ion beamlets and disallows beam spread and limits the beam divergence during transients and steady state operation. The additional exit or collimating grid prevents beam divergence during turn-on and turn-off and prevents ions from hitting the periphery of the target where there is re-deposited material or from missing the target and hitting the wall of the vessel where there is deposited material, thereby preventing defects from being deposited on a substrate to be coated. Thus, the addition of a collimating grid to an ion source ensures that the ion beam will hit and be confined to a specific target area.

  6. Defect localization, characterization and reliability assessment in emerging photovoltaic devices.

    SciTech Connect (OSTI)

    Yang, Benjamin Bing-Yeh; Cruz-Campa, Jose Luis; Haase, Gad S.; Tangyunyong, Paiboon; Cole, Edward Isaac,; Okandan, Murat; Nielson, Gregory N.

    2014-04-01

    Microsystems-enabled photovoltaics (MEPV) can potentially meet increasing demands for light-weight, portable, photovoltaic solutions with high power density and efficiency. The study in this report examines failure analysis techniques to perform defect localization and evaluate MEPV modules. CMOS failure analysis techniques, including electroluminescence, light-induced voltage alteration, thermally-induced voltage alteration, optical beam induced current, and Seabeck effect imaging were successfully adapted to characterize MEPV modules. The relative advantages of each approach are reported. In addition, the effects of exposure to reverse bias and light stress are explored. MEPV was found to have good resistance to both kinds of stressors. The results form a basis for further development of failure analysis techniques for MEPVs of different materials systems or multijunction MEPVs. The incorporation of additional stress factors could be used to develop a reliability model to generate lifetime predictions for MEPVs as well as uncover opportunities for future design improvements.

  7. Yield improvement and defect reduction in steel casting

    SciTech Connect (OSTI)

    Kent Carlson

    2004-03-16

    This research project investigated yield improvement and defect reduction techniques in steel casting. Research and technology development was performed in the following three specific areas: (1) Feeding rules for high alloy steel castings; (2) Unconventional yield improvement and defect reduction techniques--(a) Riser pressurization; and (b) Filling with a tilting mold; and (3) Modeling of reoxidation inclusions during filling of steel castings. During the preparation of the proposal for this project, these areas were identified by the High Alloy Committee and Carbon and Low Alloy Committee of the Steel Founders' Society of America (SFSA) as having the highest research priority to the steel foundry industry. The research in each of the areas involved a combination of foundry experiments, modeling and simulation. Numerous SFSA member steel foundries participated in the project through casting trials and meetings. The technology resulting from this project will result in decreased scrap and rework, casting yield improvement, and higher quality steel castings produced with less iteration. This will result in considerable business benefits to steel foundries, primarily due to reduced energy and labor costs, increased capacity and productivity, reduced lead-time, and wider use and application of steel castings. As estimated using energy data provided by the DOE, the technology produced as a result of this project will result in an energy savings of 2.6 x 10{sup 12} BTU/year. This excludes the savings that were anticipated from the mold tilting research. In addition to the energy savings, and corresponding financial savings this implies, there are substantial environmental benefits as well. The results from each of the research areas listed above are summarized.

  8. A Cost-Driven Fracture Heuristics to Minimize External Sliver Length

    E-Print Network [OSTI]

    Zakhor, Avideh

    A Cost-Driven Fracture Heuristics to Minimize External Sliver Length Xu Ma, Shangliang Jiang lithography, mask pattern is first fractured into basic trapezoids, and then fabricated by the variable shaped beam mask writing machine. Ideally, mask fracture tools aim at both suppressing the trapezoid count

  9. Using Simulation for Assessing the Real Impact of Test Coverage on Defect Lionel C. Briand

    E-Print Network [OSTI]

    Carleton University

    AT acceptance test IT integration test UT unit test Notation dc defect coverage tc test coverage ti test coverage measures) Test coverage is measured as the percentage of constructs - as defined by the coverageUsing Simulation for Assessing the Real Impact of Test Coverage on Defect Coverage Lionel C. Briand

  10. Using Explicit and Machine-Understandable Engineering Knowledge for Defect Detection in Automation Systems Engineering

    E-Print Network [OSTI]

    industrial complexes are very high. Traditional approaches for defect detection in automation systems and data models which are used within the engineering of industrial automation systems. Thus, some defects Nowadays, industrial automation systems have tendencies to become more and more complex and large

  11. Radiation Effects & Defects in Solids Vol. 164, No. 10, October 2009, 585591

    E-Print Network [OSTI]

    Pandey, Ravi

    and oxygen impurity in AlN: spintronic quantum dots J.M. Vaila,b *, T. Haroonc , J. Hernandez-Melgara,b , D) Point defects with non-zero spin are prototypical spintronic quantum dots. Here two anion-site defects and local mode force constants. The relevance to spintronic quantum dots in semiconductors is discussed

  12. Electrochemical method for defect delineation in silicon-on-insulator wafers

    DOE Patents [OSTI]

    Guilinger, Terry R. (Albuquerque, NM); Jones, Howland D. T. (Albuquerque, NM); Kelly, Michael J. (Albuquerque, NM); Medernach, John W. (Albuquerque, NM); Stevenson, Joel O. (Albuquerque, NM); Tsao, Sylvia S. (Albuquerque, NM)

    1991-01-01

    An electrochemical method for defect delineation in thin-film SOI or SOS wafers in which a surface of a silicon wafer is electrically connected so as to control the voltage of the surface within a specified range, the silicon wafer is then contacted with an electrolyte, and, after removing the electrolyte, defects and metal contamination in the silicon wafer are identified.

  13. The Role of Silicon Interstitials in the Formation of Boron-Oxygen Defects in Crystalline Silicon

    E-Print Network [OSTI]

    The Role of Silicon Interstitials in the Formation of Boron-Oxygen Defects in Crystalline Silicon@ise.fhg.de Keywords: crystalline silicon, Czochralski, boron-oxygen defect, silicon interstitial Abstract. Oxygen-rich crystalline silicon materials doped with boron are plagued by the presence of a well-known carrier

  14. Defect controlled transverse compressive strength of polyethylene fiber M.R. O'Masta a,

    E-Print Network [OSTI]

    Wadley, Haydn

    Defect controlled transverse compressive strength of polyethylene fiber laminates M.R. O'Masta a: Laminate defects Voids Compressive strength Polyethylene composites a b s t r a c t Using a combination weight polyethylene (UHMWPE) fibers and thermoplastic resins, and investi- gated their effects upon

  15. Production of defects in hexagonal boron nitride monolayer under ion irradiation O. Lehtinen a,

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Production of defects in hexagonal boron nitride monolayer under ion irradiation O. Lehtinen a, , E: Hexagonal boron nitride monolayer Ion irradiation Defect a b s t r a c t Atomistic computer simulations monolayer to irradiation with noble gas ions having energies from 35 eV up to 10 MeV. Probabilities

  16. Understanding structural defects in lithium-rich layered oxide cathodes Karalee A. Jarvis,a

    E-Print Network [OSTI]

    Ferreira, Paulo J.

    the required amounts of lithium, manganese, and nickel acetates were added to this solution. The molar ratioUnderstanding structural defects in lithium-rich layered oxide cathodes Karalee A. Jarvis, Accepted 31st March 2012 DOI: 10.1039/c2jm30575e Planar defects in lithium-rich layered oxides were

  17. Hydrogen-related defects in bulk ZnO Matthew D. McCluskey,1

    E-Print Network [OSTI]

    McCluskey, Matthew

    Hydrogen-related defects in bulk ZnO Matthew D. McCluskey,1 Slade J. Jokela,1 and Marianne C. Tarun. This paper reviews recent work on hydrogen donors and nitrogen-hydrogen complexes in ZnO. INTRODUCTION Zinc be understood. One such defect is hydrogen, a common impurity in ZnO. We have studied hydrogen donors using

  18. Hydrogen interaction with point defects in tungsten K. Heinola, T. Ahlgren, K. Nordlund, and J. Keinonen

    E-Print Network [OSTI]

    Nordlund, Kai

    Hydrogen interaction with point defects in tungsten K. Heinola, T. Ahlgren, K. Nordlund, and J-principles calculations were used in determining the binding and trapping properties of hydrogen to point defects in tungsten. Hydrogen zero-point vibrations were taken into account. It was concluded that the monovacancy can

  19. Faster Defect Resolution with Higher Technical Quality of Software Bart Luijten

    E-Print Network [OSTI]

    Visser, Joost

    Faster Defect Resolution with Higher Technical Quality of Software Bart Luijten Delft University of the relation between technical quality of software products and the defect resolution performance of numerous software products that have been evaluated with the SIG quality model in the context of software

  20. Stone-Wales defects in graphene and other planar sp2 -bonded materials

    E-Print Network [OSTI]

    Alavi, Ali

    that the canonical flat SW defect in graphene is in fact not a local minimum on the potential-energy surface PES have also been predicted to alter the electronic properties band structure and density of states in graphitic materials.12 However, in clean unmodified graphene it is customarily assumed that SW defects

  1. The relationship between grain boundary structure, defect mobility, and grain boundary sink efficiency

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Uberuaga, Blas Pedro; Vernon, Louis J.; Martinez, Enrique; Voter, Arthur F.

    2015-03-13

    Nanocrystalline materials have received great attention due to their potential for improved functionality and have been proposed for extreme environments where the interfaces are expected to promote radiation tolerance. However, the precise role of the interfaces in modifying defect behavior is unclear. Using long-time simulations methods, we determine the mobility of defects and defect clusters at grain boundaries in Cu. We find that mobilities vary significantly with boundary structure and cluster size, with larger clusters exhibiting reduced mobility, and that interface sink efficiency depends on the kinetics of defects within the interface via the in-boundary annihilation rate of defects. Thus,more »sink efficiency is a strong function of defect mobility, which depends on boundary structure, a property that evolves with time. Further, defect mobility at boundaries can be slower than in the bulk, which has general implications for the properties of polycrystalline materials. Finally, we correlate defect energetics with the volumes of atomic sites at the boundary.« less

  2. DISSERTATION Role of the Cu-O Defect in CdTe Solar Cells

    E-Print Network [OSTI]

    Sites, James R.

    DISSERTATION Role of the Cu-O Defect in CdTe Solar Cells Submitted by Caroline R. Corwine OF THE CU-O DEFECT COMPLEX IN CDTE SOLAR CELLS Thin-film CdTe is one of the leading materials used in photovoltaic (PV) solar cells. One way to improve device performance and stability is through understanding how

  3. Mesoscopic pointlike defects in semiconductors: Deep-level energies D. D. Nolte

    E-Print Network [OSTI]

    Nolte, David D.

    Mesoscopic pointlike defects in semiconductors: Deep-level energies D. D. Nolte Department in common with quantum dots, such as Coulomb-charging energies, but unlike quantum dots their electronic properties are dominated by the covalent bond energies of the defect-semiconductor interface. The deep

  4. Internal hydriding in irradiated defected Zircaloy fuel rods: A review (LWBR Development Program)

    SciTech Connect (OSTI)

    Clayton, J C

    1987-10-01

    Although not a problem in recent commercial power reactors, including the Shippingport Light Water Breeder Reactor, internal hydriding of Zircaloy cladding was a persistent cause of gross cladding failures during the 1960s. It occurred in the fuel rods of water-cooled nuclear power reactors that had a small cladding defect. This report summarizes the experimental findings, causes, mechanisms, and methods of minimizing internal hydriding in defected Zircaloy-clad fuel rods. Irradiation test data on the different types of defected fuel rods, intentionally fabricated defected and in-pile operationally defected rods, are compared. Significant factors affecting internal hydriding in defected Zircaloy-clad fuel rods (defect hole size, internal and external sources of hydrogen, Zircaloy cladding surface properties, nickel alloy contamination of Zircaloy, the effect of heat flux and fluence) are discussed. Pertinent in-pile and out-of-pile test results from Bettis and other laboratories are used as a data base in constructing a qualitative model which explains hydrogen generation and distribution in Zircaloy cladding of defected water-cooled reactor fuel rods. Techniques for minimizing internal hydride failures in Zircaloy-clad fuel rods are evaluated.

  5. MAGNETIC FLUX LEAKAGE INVESTIGATION OF INTERACTING DEFECTS: COMPETITIVE EFFECTS OF STRESS CONCENTRATION AND MAGNETIC SHIELDING

    E-Print Network [OSTI]

    Clapham, Lynann

    CONCENTRATION AND MAGNETIC SHIELDING C Mandache1,2 and L Clapham1 1 Queen's University, Kingston, Ontario, K7L 3 of their stress concentrations and by the mutual shielding of the defects from the applied flux density. This type and magnetic flux shielding further complicates the defect-induced MFL signal calibration [6]. The focus

  6. Submitted for publication Production of defects in supported carbon nanotubes under ion irradiation

    E-Print Network [OSTI]

    Nordlund, Kai

    Submitted for publication Production of defects in supported carbon nanotubes under ion irradiation University of Helsinki, Finland (December 10, 2001) Ion irradiation of individual carbon nanotubes deposited near irradiation-induced defects. 81.07.De, 61.48+c, 61.80.Jh,73.22.-f I. INTRODUCTION Recent

  7. Stability of irradiation-induced point defects on walls of carbon nanotubes A. V. Krasheninnikova)

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Stability of irradiation-induced point defects on walls of carbon nanotubes A. V. Krasheninnikova study the structure and stability of atomic-scale irradiation-induced defects on walls of carbon-dose, low-temperature ion irradiation, we model the temporal evolution of single vacancies and vacancy

  8. Defects in articular cartilage metabolism and early arthritis in fibroblast growth factor receptor 3

    E-Print Network [OSTI]

    Buschmann, Michael

    Defects in articular cartilage metabolism and early arthritis in fibroblast growth factor receptor Laboratory, Shriner's Hospital for Children and 3 Centre for Bone and Periodontal Research, McGill University technology for cartilage tissue engineering and assisted repair. Assisted repair of focal defects

  9. Modeling the probability of excitation and the defective part level as testing progresses 

    E-Print Network [OSTI]

    Dworak, Jennifer Lynn

    2000-01-01

    The primary purpose of digital circuit manufacture testing is to detect defective parts so that they will not be sold to customers. Predicting the defective part level, which results after a set of test patterns has been applied, is not a simple...

  10. Defect transition energies and the density of electronic states in hydrogenated amorphous silicon

    E-Print Network [OSTI]

    Tolk, Norman H.

    Defect transition energies and the density of electronic states in hydrogenated amorphous silicon G in hydrogenated amorphous silicon (a-Si:H). These measurements suggest that the density of neutral defects is much of the corresponding transition energies are determined and agree with two models proposed to describe the density

  11. Exploring the interaction between lithium ion and defective graphene surface using dispersion corrected DFT studies

    SciTech Connect (OSTI)

    Vijayakumar, M.; Hu, Jian Z.

    2013-10-15

    To analyze the lithium ion interaction with realistic graphene surfaces, we carried out dispersion corrected DFT-D3 studies on graphene with common point defects and chemisorbed oxygen containing functional groups along with defect free graphene surface. Our study reveals that, the interaction between lithium ion (Li+) and graphene is mainly through the delocalized ? electron of pure graphene layer. However, the oxygen containing functional groups pose high adsorption energy for lithium ion due to the Li-O ionic bond formation. Similarly, the point defect groups interact with lithium ion through possible carbon dangling bonds and/or cation-? type interactions. Overall these defect sites render a preferential site for lithium ions compared with pure graphene layer. Based on these findings, the role of graphene surface defects in lithium battery performance were discussed.

  12. Computer code for the atomistic simulation of lattice defects and dynamics. [COMENT code

    SciTech Connect (OSTI)

    Schiffgens, J.O.; Graves, N.J.; Oster, C.A.

    1980-04-01

    This document has been prepared to satisfy the need for a detailed, up-to-date description of a computer code that can be used to simulate phenomena on an atomistic level. COMENT was written in FORTRAN IV and COMPASS (CDC assembly language) to solve the classical equations of motion for a large number of atoms interacting according to a given force law, and to perform the desired ancillary analysis of the resulting data. COMENT is a dual-purpose intended to describe static defect configurations as well as the detailed motion of atoms in a crystal lattice. It can be used to simulate the effect of temperature, impurities, and pre-existing defects on radiation-induced defect production mechanisms, defect migration, and defect stability.

  13. Interaction of Sn atoms with defects introduced by ion implantation in Ge substrate

    SciTech Connect (OSTI)

    Taoka, Noriyuki, E-mail: ntaoka@alice.xtal.nagoya-u.ac.jp; Fukudome, Motoshi; Takeuchi, Wakana; Arahira, Takamitsu; Sakashita, Mitsuo; Nakatsuka, Osamu; Zaima, Shigeaki [Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2014-05-07

    The interaction of Sn atoms with defects induced by Sn implantation of Ge substrates with antimony (Sb) as an n-type dopant and the impact of H{sub 2} annealing on these defects were investigated by comparison with defects induced by Ge self-implantation. In the Ge samples implanted with either Sn or Ge, and annealed at temperatures of less than 200?°C, divacancies, Sb-vacancy complexes with single or double acceptor-like states, and defects related to Sb and interstitial Ge atoms were present. On the other hand, after annealing at 500?°C in an N{sub 2} or H{sub 2} atmosphere, defects with different structures were observed in the Sn-implanted samples by deep level transition spectroscopy. The energy levels of the defects were 0.33?eV from the conduction band minimum and 0.55?eV from the valence band maximum. From the capacitance-voltage (C-V) characteristics, interaction between Sn atoms and defects after annealing at 500?°C was observed. The effect of H{sub 2} annealing at around 200?°C was observed in the C-V characteristics, which can be attributed to hydrogen passivation, and this effect was observed in both the Ge- and Sn-implanted samples. These results suggest the presence of defects that interact with Sn or hydrogen atoms. This indicates the possibility of defect control in Ge substrates by Sn or hydrogen incorporation. Such defect control could yield high-performance Ge-based devices.

  14. First-principles study of noble gas impurities and defects in UO{sub 2}

    SciTech Connect (OSTI)

    Thompson, Alexander E.; Wolverton, C.

    2011-10-01

    We performed a series of density functional theory + U (DFT + U) calculations to explore the energetics of various defects in UO{sub 2}, i.e., noble gases (He, Ne, Ar, Kr, Xe), Schottky defects, and the interaction between these defects. We found the following: (1) collinear antiferromagnetic UO{sub 2} has an energy-lowering distortion of the oxygen sublattice from ideal fluorite positions; (2) DFT + U qualitatively affects the formation volume of Schottky defect clusters in UO{sub 2} (without U the formation volume is negative, but including U the formation volume is positive); (3) the configuration of the Schottky defect cluster is dictated by a competition between electrostatic and surface energy effects; (4) the incorporation energy of inserting noble gas atoms into an interstitial site has a strong dependence on the volume of the noble gas atom, corresponding to the strain it causes in the interstitial site, from He (0.98 eV) to Xe (9.73 eV); (5) the energetics of each of the noble gas atoms incorporated in Schottky defects show strong favorable binding, due to strain relief associated with moving the noble gas atom from the highly strained interstitial position into the vacant space of the Schottky defect; and (6) for argon, krypton, and xenon, the binding energy of a noble gas impurity with the Schottky defect is larger than the formation energy of a Schottky defect, thereby making the formation of Schottky defects thermodynamically favorable in the presence of these large impurities.

  15. Auto Defect Classification (ADC) Value for Patterned Wafer Inspection Systems in PLY Within a High Volume Wafer Manufacturing Fabrication Facility

    E-Print Network [OSTI]

    Durniak, John

    2010-05-14

    The purpose of this investigation is to demonstrate value for Auto Defect Classification (ADC) for patterned wafer inspection systems within a high volume manufacturing fabrication in the Process Limited Yield (PLY) defect area. Process excursions...

  16. Characterization of V-shaped defects in 4H-SiC homoepitaxial layers

    SciTech Connect (OSTI)

    Zhang, Lihua; Su, Dong; Kisslinger, Kim; Stach, Eric; Chung, Gil; Zhang, Jie; Thomas, Bernd; Sanchez, Edward K; Mueller, Stephan G.; Hansen, Darren; Loboda, Mark J.; Wu, Fangzhen; Wang, Huanhuan; Raghothamachar, Balaji; Dudley, Michael

    2014-12-04

    Synchrotron white beam x-ray topography images show that faint needle-like surface morphological features observed on the Si-face of 4H-SiC homoepitaxial layers using Nomarski optical microscopy are associated with V shaped stacking faults in the epilayer. KOH etching of the V shaped defect reveals small oval pits connected by a shallow line which corresponding to the surface intersections of two partial dislocations and the stacking fault connecting them. Transmission electron microscopy (TEM) specimens from regions containing the V shaped defects were prepared using focused ion beam milling, and stacking sequences of (85), (50) and (63) are observed at the faulted region with high resolution TEM. In order to study the formation mechanism of V shaped defect, low dislocation density 4H-SiC substrates were chosen for epitaxial growth, and the corresponding regions before and after epitaxy growth are compared in SWBXT images. It is found that no defects in the substrate are directly associated with the formation of the V shaped defect. Simulation results of the contrast from the two partial dislocations associated with V shaped defect in synchrotron monochromatic beam x-ray topography reveals the opposite sign nature of their Burgers vectors. Therefore, a mechanism of 2D nucleation during epitaxy growth is postulated for the formation of the V shaped defect, which requires elimination of non-sequential 1/4[0001] bilayers from the original structure to create the observed faulted stacking sequence.

  17. Characterization of V-shaped defects in 4H-SiC homoepitaxial layers

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Lihua; Su, Dong; Kisslinger, Kim; Stach, Eric; Chung, Gil; Zhang, Jie; Thomas, Bernd; Sanchez, Edward K; Mueller, Stephan G.; Hansen, Darren; et al

    2014-12-04

    Synchrotron white beam x-ray topography images show that faint needle-like surface morphological features observed on the Si-face of 4H-SiC homoepitaxial layers using Nomarski optical microscopy are associated with V shaped stacking faults in the epilayer. KOH etching of the V shaped defect reveals small oval pits connected by a shallow line which corresponding to the surface intersections of two partial dislocations and the stacking fault connecting them. Transmission electron microscopy (TEM) specimens from regions containing the V shaped defects were prepared using focused ion beam milling, and stacking sequences of (85), (50) and (63) are observed at the faulted regionmore »with high resolution TEM. In order to study the formation mechanism of V shaped defect, low dislocation density 4H-SiC substrates were chosen for epitaxial growth, and the corresponding regions before and after epitaxy growth are compared in SWBXT images. It is found that no defects in the substrate are directly associated with the formation of the V shaped defect. Simulation results of the contrast from the two partial dislocations associated with V shaped defect in synchrotron monochromatic beam x-ray topography reveals the opposite sign nature of their Burgers vectors. Therefore, a mechanism of 2D nucleation during epitaxy growth is postulated for the formation of the V shaped defect, which requires elimination of non-sequential 1/4[0001] bilayers from the original structure to create the observed faulted stacking sequence.« less

  18. Evolution of iron-containing defects during processing of Si solar cells

    SciTech Connect (OSTI)

    Mchedlidze, Teimuraz Weber, Jörg; Möller, Christian; Lauer, Kevin

    2014-12-28

    The formation of iron-containing defects was studied during the fabrication process of a Si solar cell. Three Cz-Si crystals with different iron content in the feedstock were grown for the study. Iron-containing defects in and near-to the n{sup +}p-junction volume (NJV) of the cells are formed directly after phosphorus diffusion due to an inflow of iron atoms from the dissolving iron-silicide precipitates. These NJV-defects strongly affect the dark saturation current of the junctions. Partial dissolution or gettering of the NJV-defects during formation of the antireflection coating is accompanied by an increase in defect concentrations in the bulk of the cell. Further deterioration of bulk carrier lifetime during the formation of electrical contacts is related to the partial dissolution of remaining iron-silicide precipitates during the firing process. A general description of the defect evolution in iron-contaminated wafers during solar cell processing is presented and possible strategies for reducing the influence of iron-containing defects are proposed.

  19. Screening method for selecting semiconductor substrates having defects below a predetermined level in an oxide layer

    DOE Patents [OSTI]

    Warren, W.L.; Vanheusden, K.J.R.; Schwank, J.R.; Fleetwood, D.M.; Shaneyfelt, M.R.; Winokur, P.S.; Devine, R.A.B.

    1998-07-28

    A method is disclosed for screening or qualifying semiconductor substrates for integrated circuit fabrication. The method comprises the steps of annealing at least one semiconductor substrate at a first temperature in a defect-activating ambient (e.g. hydrogen, forming gas, or ammonia) for sufficient time for activating any defects within on oxide layer of the substrate; measuring a defect-revealing electrical characteristic of at least a portion of the oxide layer for determining a quantity of activated defects therein; and selecting substrates for which the quantity of activated defects is below a predetermined level. The defect-revealing electrical characteristic may be a capacitance-versus voltage (C-V) characteristic or a current-versus-voltage (I-V) characteristic that is dependent on an electrical charge in the oxide layer generated by the activated defects. Embodiments of the present invention may be applied for screening any type of semiconductor substrate or wafer having an oxide layer formed thereon or therein. This includes silicon-on-insulator substrates formed by a separation by the implantation of oxygen (SIMOX) process or the bond and etch back silicon-on-insulator (BESOI) process, as well as silicon substrates having a thermal oxide layer or a deposited oxide layer. 5 figs.

  20. Screening method for selecting semiconductor substrates having defects below a predetermined level in an oxide layer

    DOE Patents [OSTI]

    Warren, William L. (Albuquerque, NM); Vanheusden, Karel J. R. (Albuquerque, NM); Schwank, James R. (Albuquerque, NM); Fleetwood, Daniel M. (Albuquerque, NM); Shaneyfelt, Marty R. (Albuquerque, NM); Winokur, Peter S. (Albuquerque, NM); Devine, Roderick A. B. (St. Martin le Vinoux, FR)

    1998-01-01

    A method for screening or qualifying semiconductor substrates for integrated circuit fabrication. The method comprises the steps of annealing at least one semiconductor substrate at a first temperature in a defect-activating ambient (e.g. hydrogen, forming gas, or ammonia) for sufficient time for activating any defects within on oxide layer of the substrate; measuring a defect-revealing electrical characteristic of at least a portion of the oxide layer for determining a quantity of activated defects therein; and selecting substrates for which the quantity of activated defects is below a predetermined level. The defect-revealing electrical characteristic may be a capacitance-versus-voltage (C-V) characteristic or a current-versus-voltage (I-V) characteristic that is dependent on an electrical charge in the oxide layer generated by the activated defects. Embodiments of the present invention may be applied for screening any type of semiconductor substrate or wafer having an oxide layer formed thereon or therein. This includes silicon-on-insulator substrates formed by a separation by the implantation of oxygen (SIMOX) process or the bond and etch back silicon-on-insulator (BESOI) process, as well as silicon substrates having a thermal oxide layer or a deposited oxide layer.

  1. Phonons and defects in semiconductors and nanostructures: Phonon trapping, phonon scattering, and heat flow at heterojunctions

    SciTech Connect (OSTI)

    Estreicher, S. K., E-mail: Stefan.Estreicher@ttu.edu; Gibbons, T. M.; Kang, By.; Bebek, M. B. [Physics Department, Texas Tech University, Lubbock, Texas 79409-1051 (United States)

    2014-01-07

    Defects in semiconductors introduce vibrational modes that are distinct from bulk modes because they are spatially localized in the vicinity of the defect. Light impurities produce high-frequency modes often visible by Fourier-transform infrared absorption or Raman spectroscopy. Their vibrational lifetimes vary by orders of magnitude and sometimes exhibit unexpectedly large isotope effects. Heavy impurities introduce low-frequency modes sometimes visible as phonon replicas in photoluminescence bands. But other defects such as surfaces or interfaces exhibit spatially localized modes (SLMs) as well. All of them can trap phonons, which ultimately decay into lower-frequency bulk phonons. When heat flows through a material containing defects, phonon trapping at localized modes followed by their decay into bulk phonons is usually described in terms of phonon scattering: defects are assumed to be static scattering centers and the properties of the defect-related SLMs modes are ignored. These dynamic properties of defects are important. In this paper, we quantify the concepts of vibrational localization and phonon trapping, distinguish between normal and anomalous decay of localized excitations, discuss the meaning of phonon scattering in real space at the atomic level, and illustrate the importance of phonon trapping in the case of heat flow at Si/Ge and Si/C interfaces.

  2. Chiral asymmetry in propagation of soliton defects in crystalline backgrounds

    E-Print Network [OSTI]

    Arancibia, Adrian

    2015-01-01

    By applying Darboux-Crum transformations to the Lax pair formulation of the Korteweg-de Vries (KdV) equation, we construct new sets of multi-soliton solutions to it as well as to the modified Korteweg-de Vries (mKdV) equation. The obtained solutions exhibit a chiral asymmetry in propagation of different types defects in crystalline backgrounds. We show that the KdV solitons of pulse and compression modulation types, which support bound states in semi-infinite and finite forbidden bands in the spectrum of the perturbed quantum one-gap Lame system, propagate in opposite directions with respect to the asymptotically periodic background. A similar but more complicated picture also appears for the multi-kink-antikink mKdV solitons that propagate with a privileged direction over topologically trivial or topologically nontrivial crystalline background in dependence on position of energy levels of the trapped bound states in spectral gaps of the associated Dirac system. Exotic N=4 nonlinear supersymmetric structure i...

  3. Oxide Film and Porosity Defects in Magnesium Alloy AZ91

    SciTech Connect (OSTI)

    Wang, Liang [Mississippi State University (MSU); Rhee, Hongjoo [Mississippi State University (MSU); Felicelli, Sergio D. [Mississippi State University (MSU); Sabau, Adrian S [ORNL; Berry, John T. [Mississippi State University (MSU)

    2009-01-01

    Porosity is a major concern in the production of light metal parts. This work aims to identify some of the mechanisms of microporosity formation in magnesium alloy AZ91. Microstructure analysis was performed on several samples obtained from gravity-poured ingots in graphite plate molds. Temperature data during cooling was acquired with type K thermocouples at 60 Hz at three locations of each casting. The microstructure of samples extracted from the regions of measured temperature was then characterized with optical metallography. Tensile tests and conventional four point bend tests were also conducted on specimens cut from the cast plates. Scanning electron microscopy was then used to observe the microstructure on the fracture surface of the specimens. The results of this study revealed the existence of abundant oxide film defects, similar to those observed in aluminum alloys. Remnants of oxide films were detected on some pore surfaces, and folded oxides were observed in fracture surfaces indicating the presence of double oxides entrained during pouring.

  4. Control of Suspect/Counterfeit and Defective Items

    SciTech Connect (OSTI)

    Sheriff, Marnelle L.

    2013-09-03

    This procedure implements portions of the requirements of MSC-MP-599, Quality Assurance Program Description. It establishes the Mission Support Alliance (MSA) practices for minimizing the introduction of and identifying, documenting, dispositioning, reporting, controlling, and disposing of suspect/counterfeit and defective items (S/CIs). employees whose work scope relates to Safety Systems (i.e., Safety Class [SC] or Safety Significant [SS] items), non-safety systems and other applications (i.e., General Service [GS]) where engineering has determined that their use could result in a potential safety hazard. MSA implements an effective Quality Assurance (QA) Program providing a comprehensive network of controls and verification providing defense-in-depth by preventing the introduction of S/CIs through the design, procurement, construction, operation, maintenance, and modification of processes. This procedure focuses on those safety systems, and other systems, including critical load paths of lifting equipment, where the introduction of S/CIs would have the greatest potential for creating unsafe conditions.

  5. Please cite this article in press as: S. Selvarasah, et al., A reusable high aspect ratio parylene-C shadow mask technology for diverse micropat-terning applications, Sens. Actuators A: Phys. (2007), doi:10.1016/j.sna.2007.10.053

    E-Print Network [OSTI]

    Sridhar, Srinivas

    2007-01-01

    .sciencedirect.com Sensors and Actuators A xxx (2007) xxx­xxx A reusable high aspect ratio parylene-C shadow mask technologyPlease cite this article in press as: S. Selvarasah, et al., A reusable high aspect ratio parylene-C shadow mask technology for diverse micropat- terning applications, Sens. Actuators A: Phys. (2007), doi

  6. The RF performance of cavity made from defective niobium material determined by Eddy Current Scanning

    SciTech Connect (OSTI)

    Wu, G.; Cooley, L.; Sergatskov, D.; Ozelis, J.; /Fermilab; Brinkmann, A.; Singer, W.; Singer, X.; /DESY; Pekeler, M.

    2010-10-01

    Eddy current scanning (ECS) has been used to screen niobium sheets to avoid defective material being used in costly cavity fabrication. The evaluation criterion of this quality control tool is not well understood. Past surface studies showed some features were shallow enough to be removed by chemical etching. The remaining features were identified to be small number of deeper inclusions, but mostly unidentifiable features (by chemical analysis). A real cavity made of defective niobium material has been tested. The cavity achieved high performance with comparable results to the cavities made from defect free cavities. Temperature mapping could help to define the control standard clearly.

  7. Kinetic model for electric-field induced point defect redistribution near semiconductor surfaces

    SciTech Connect (OSTI)

    Gorai, Prashun; Seebauer, Edmund G.

    2014-07-14

    The spatial distribution of point defects near semiconductor surfaces affects the efficiency of devices. Near-surface band bending generates electric fields that influence the spatial redistribution of charged mobile defects that exchange infrequently with the lattice, as recently demonstrated for pile-up of isotopic oxygen near rutile TiO{sub 2} (110). The present work derives a mathematical model to describe such redistribution and establishes its temporal dependence on defect injection rate and band bending. The model shows that band bending of only a few meV induces significant redistribution, and that the direction of the electric field governs formation of either a valley or a pile-up.

  8. Structural defects in GaN revealed by Transmission Electron Microscopy

    SciTech Connect (OSTI)

    Liliental-Weber, Zuzanna

    2014-04-18

    This paper reviews the various types of structural defects observed by Transmission Electron Microscopy in GaN heteroepitaxial layers grown on foreign substrates and homoepitaxial layers grown on bulk GaN substrates. The structural perfection of these layers is compared to the platelet self-standing crystals grown by High Nitrogen Pressure Solution. Defects in undoped and Mg doped GaN are discussed. Some models explaining the formation of inversion domains in heavily Mg doped layers that are possible defects responsible for the difficulties of p-doping in GaN are also reviewed.

  9. Masked-backlighter technique used to simultaneously image x-ray absorption and x-ray emission from an inertial confinement fusion plasma

    SciTech Connect (OSTI)

    Marshall, F. J., E-mail: fredm@lle.rochester.edu; Radha, P. B. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

    2014-11-15

    A method to simultaneously image both the absorption and the self-emission of an imploding inertial confinement fusion plasma has been demonstrated on the OMEGA Laser System. The technique involves the use of a high-Z backlighter, half of which is covered with a low-Z material, and a high-speed x-ray framing camera aligned to capture images backlit by this masked backlighter. Two strips of the four-strip framing camera record images backlit by the high-Z portion of the backlighter, while the other two strips record images aligned with the low-Z portion of the backlighter. The emission from the low-Z material is effectively eliminated by a high-Z filter positioned in front of the framing camera, limiting the detected backlighter emission to that of the principal emission line of the high-Z material. As a result, half of the images are of self-emission from the plasma and the other half are of self-emission plus the backlighter. The advantage of this technique is that the self-emission simultaneous with backlighter absorption is independently measured from a nearby direction. The absorption occurs only in the high-Z backlit frames and is either spatially separated from the emission or the self-emission is suppressed by filtering, or by using a backlighter much brighter than the self-emission, or by subtraction. The masked-backlighter technique has been used on the OMEGA Laser System to simultaneously measure the emission profiles and the absorption profiles of polar-driven implosions.

  10. Induced defect nucleation and side-band instabilities in hexagons with rotation and mean flow

    E-Print Network [OSTI]

    Yuan-Nan Young; Hermann Riecke

    2002-07-30

    The combined effect of mean flow and rotation on hexagonal patterns is investigated using Ginzburg-Landau equations that include nonlinear gradient terms as well as the nonlocal coupling provided by the mean flow. Long-wave and short-wave side-band instabilities are determined. Due to the nonlinear gradient terms and enhanced by the mean flow, the penta-hepta defects can become unstable to the induced nucleation of dislocations in the defect-free amplitude, which can lead to the proliferation of penta-hepta defects and persistent spatio-temporal chaos. For individual penta-hepta defects the nonlinear gradient terms enhance climbing or gliding motion, depending on whether they break the chiral symmetry or not.

  11. Detection of defects in FRP-reinforced concrete with the acoustic-laser vibrometry method

    E-Print Network [OSTI]

    Chen, Justin Gejune

    2013-01-01

    Fiber-reinforced polymer (FRP) strengthening and retrofitting of concrete structural elements has become increasingly popular for civil infrastructure systems. When defects occur in FRP-reinforced concrete elements at the ...

  12. Entropy and Kinetics of Point-Defects in Two-Dimensional Dipolar Crystals

    E-Print Network [OSTI]

    Wolfgang Lechner; David Polster; Georg Maret; Christoph Dellago; Peter Keim

    2015-02-18

    We study in experiment and with computer simulation the free energy and the kinetics of vacancy and interstitial defects in two-dimensional dipolar crystals. The defects appear in different local topologies which we characterize by their point group symmetry; $C_n$ is the n-fold cyclic group and $D_n$ is the dihedral group, including reflections. The frequency of different local topologies is not determined by their almost degenerate energies but dominated by entropy for symmetric configurations. The kinetics of the defects is fully reproduced by a master equation in a multi-state Markov model. In this model, the system is described by the state of the defect and the time evolution is given by transitions occurring with particular rates. These transition rate constants are extracted from experiments and simulations using an optimisation procedure. The good agreement between experiment, simulation and master equation thus provides evidence for the accuracy of the model.

  13. National market cow and bull beef quality audit-2007: a survey of producer-related defects 

    E-Print Network [OSTI]

    Nicholson, John David Whitson

    2009-05-15

    Packing plants (n = 23), were audited for producer-related defects found in cull cows and bulls. Interviews, live animal and carcass evaluations, and subprimal evaluations were conducted during each audit. A drastic reduction ...

  14. Graphene flakes with defective edge terminations: Universal and topological aspects, and one-dimensional quantum behavior

    E-Print Network [OSTI]

    Yannouleas, Constantine

    Graphene flakes with defective edge terminations: Universal and topological aspects, and one graphene nanoflakes with reconstructed zigzag edges, where a succes- sion of pentagons and heptagons these spectra. The electronic spectra of trigonal graphene nanoflakes with reczag edge terminations exhibit

  15. Aneuploid yeast strains exhibit defects in cell growth and passage through START

    E-Print Network [OSTI]

    Thorburn, Rebecca Ruth

    Aneuploidy, a chromosome content that is not a multiple of the haploid karyotype, is associated with reduced fitness in all organisms analyzed to date. In budding yeast aneuploidy causes cell proliferation defects, with ...

  16. Defect-induced magnetism in cobalt-doped ZnO epilayers

    SciTech Connect (OSTI)

    Ciatto, G.; Fonda, E.; Trolio, A. Di; Alippi, P.; Varvaro, G.; Bonapasta, A. Amore; Polimeni, A.; Capizzi, M.

    2014-02-21

    We used a synergic Co-edge X-ray absorption spectroscopy (XAS) and density functional theory calculations approach to perform a study of defects which could account for the room temperature ferromagnetism of ZnCoO, an oxide of great potential interest in semiconductor spintronics. Our results suggest that a key role is played by specific defect complexes in which O vacancies are located close to the Co atoms. Extended defects such as Co clusters have a marginal function, although we observe their formation at the epilayer surface under certain growth conditions. We also show preliminary results of the study of hydrogen-induced defects in ZnCoO epilayers deliberately hydrogen irradiated via a Kaufman source. Hydrogen was in fact predicted to mediate a ferromagnetic spin-spin interaction between neighboring magnetic impurities.

  17. Surface-induced charge state conversion of nitrogen-vacancy defects in nanodiamonds

    E-Print Network [OSTI]

    L. Rondin; G. Dantelle; A. Slablab; F. Grosshans; F. Treussart; P. Bergonzo; S. Perruchas; T. Gacoin; M. Chaigneau; H. -C. Chang; V. Jacques; J. -F. Roch

    2010-10-19

    We present a study of the charge state conversion of single nitrogen-vacancy (NV) defects hosted in nanodiamonds (NDs). We first show that the proportion of negatively-charged NV$^{-}$ defects, with respect to its neutral counterpart NV$^{0}$, decreases with the size of the ND. We then propose a simple model based on a layer of electron traps located at the ND surface which is in good agreement with the recorded statistics. By using thermal oxidation to remove the shell of amorphous carbon around the NDs, we demonstrate a significant increase of the proportion of NV$^{-}$ defects in 10-nm NDs. These results are invaluable for further understanding, control and use of the unique properties of negatively-charged NV defects in diamond

  18. Impact of defect type on hydrogen passivation effectiveness in multicrystalline silicon solar cells

    E-Print Network [OSTI]

    Bertoni, Mariana I.

    In this work we examine the effectiveness of hydrogen passivation at grain boundaries as a function of defect type and microstructure in multicrystalline silicon. We analyze a specially prepared solar cell with alternating ...

  19. Hydrogen effects on the point defect spectrum in Fe-C alloys

    E-Print Network [OSTI]

    Monasterio Velásquez, Paul Rene

    2008-01-01

    As part of a multi-scale approach for modeling hydrogen embrittlement in hardened steels we have investigated, employing density functional theory methods, the stability and concentrations of the point defect clusters ...

  20. Investigation on Wave Propagation Characteristics in Plates and Pipes for Identification of Structural Defect Locations 

    E-Print Network [OSTI]

    Han, Je Heon

    2013-07-31

    For successful identification of structural defects in plates and pipes, it is essential to understand structural wave propagation characteristics such as dispersion relations. Analytical approaches to identify the dispersion relations...