National Library of Energy BETA

Sample records for ultramar diamond shamrock

  1. Diamond Shamrock nears completion of major expansions

    SciTech Connect (OSTI)

    True, W.R.

    1993-05-24

    With completion later this year of a second refined products line into Colorado, Diamond Shamrock Inc., San Antonio, will have added more than 600 miles of product and crude-oil pipeline on its system and expanded charge and production capacities at its two state-of-the-art refineries, all within 30 months. The projects aim at improving the company's ability to serve markets in the U.S. Southwest and increasing capacities and flexibility at its two refineries. The paper describes these projects under the following headings: new products service; another new line; and refineries, crude pipelines; Three Rivers expansion and Supplies for McKee.

  2. Financial News for Major Energy Companies, October - December...

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    The mergers of Chevron and Texaco, El Paso and Coastal, Phillips and Tosco, and Valero and Ultramar Diamond Shamrock (see the Mergers and Alliances web page maintained by EIA for ...

  3. Presentation title: This can be up to 2 lines

    U.S. Energy Information Administration (EIA) Indexed Site

    Genealogy of major U.S. refiners 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Amoco SOHIO BP ARCO Mapco Williams Clark Refining 1/89 12/98 4/00 3/98 Orion Diamond Shamrock Ultramar k 12/96 7/03 Ultramar Diamond Shamrock (UDS) Total North America UDS 9/97 Valero Salomon (Basis) Valero Williams BP BP b BP-Husky Refining LLC (jv) Husky Huntway 5/97 6/01 9/05 Valero Premcor g Valero Valero Valero 12/01 7/94 e 12/98 f Carlyle Group y Coastal 3/03 d 12/88 a 6/01 o Sun Company

  4. Diamond fiber field emitters

    DOE Patents [OSTI]

    Blanchet-Fincher, Graciela B.; Coates, Don M.; Devlin, David J.; Eaton, David F.; Silzars, Aris K.; Valone, Steven M.

    1996-01-01

    A field emission electron emitter comprising an electrode formed of at least one diamond, diamond-like carbon or glassy carbon composite fiber, said composite fiber having a non-diamond core and a diamond, diamond-like carbon or glassy carbon coating on said non-diamond core, and electronic devices employing such a field emission electron emitter.

  5. Electrically conductive diamond electrodes

    DOE Patents [OSTI]

    Swain, Greg; Fischer, Anne ,; Bennett, Jason; Lowe, Michael

    2009-05-19

    An electrically conductive diamond electrode and process for preparation thereof is described. The electrode comprises diamond particles coated with electrically conductive doped diamond preferably by chemical vapor deposition which are held together with a binder. The electrodes are useful for oxidation reduction in gas, such as hydrogen generation by electrolysis.

  6. Thermally stable diamond brazing

    DOE Patents [OSTI]

    Radtke, Robert P.

    2009-02-10

    A cutting element and a method for forming a cutting element is described and shown. The cutting element includes a substrate, a TSP diamond layer, a metal interlayer between the substrate and the diamond layer, and a braze joint securing the diamond layer to the substrate. The thickness of the metal interlayer is determined according to a formula. The formula takes into account the thickness and modulus of elasticity of the metal interlayer and the thickness of the TSP diamond. This prevents the use of a too thin or too thick metal interlayer. A metal interlayer that is too thin is not capable of absorbing enough energy to prevent the TSP diamond from fracturing. A metal interlayer that is too thick may allow the TSP diamond to fracture by reason of bending stress. A coating may be provided between the TSP diamond layer and the metal interlayer. This coating serves as a thermal barrier and to control residual thermal stress.

  7. Diamond tool machining of materials which react with diamond

    DOE Patents [OSTI]

    Lundin, Ralph L.; Stewart, Delbert D.; Evans, Christopher J.

    1992-01-01

    Apparatus for the diamond machining of materials which detrimentally react with diamond cutting tools in which the cutting tool and the workpiece are chilled to very low temperatures. This chilling halts or retards the chemical reaction between the workpiece and the diamond cutting tool so that wear rates of the diamond tool on previously detrimental materials are comparable with the diamond turning of materials which do not react with diamond.

  8. Diamond tool machining of materials which react with diamond

    DOE Patents [OSTI]

    Lundin, R.L.; Stewart, D.D.; Evans, C.J.

    1992-04-14

    An apparatus is described for the diamond machining of materials which detrimentally react with diamond cutting tools in which the cutting tool and the workpiece are chilled to very low temperatures. This chilling halts or retards the chemical reaction between the workpiece and the diamond cutting tool so that wear rates of the diamond tool on previously detrimental materials are comparable with the diamond turning of materials which do not react with diamond. 1 figs.

  9. Amorphous diamond films

    DOE Patents [OSTI]

    Falabella, Steven

    1998-01-01

    Amorphous diamond films having a significant reduction in intrinsic stress are prepared by biasing a substrate to be coated and depositing carbon ions thereon under controlled temperature conditions.

  10. Diamond nucleation using polyethene

    DOE Patents [OSTI]

    Morell, Gerardo; Makarov, Vladimir; Varshney, Deepak; Weiner, Brad

    2013-07-23

    The invention presents a simple, non-destructive and non-abrasive method of diamond nucleation using polyethene. It particularly describes the nucleation of diamond on an electrically viable substrate surface using polyethene via chemical vapor deposition (CVD) technique in a gaseous environment.

  11. Diamond films: Historical perspective

    SciTech Connect (OSTI)

    Messier, R.

    1993-01-01

    This section is a compilation of notes and published international articles about the development of methods of depositing diamond films. Vapor deposition articles are included from American, Russian, and Japanese publications. The international competition to develop new deposition methodologies is stressed. The current status of chemical vapor deposition of diamond is assessed.

  12. Ultrananocrystalline Diamond (UNCD) Seal Faces | Department of...

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

    Ultrananocrystalline Diamond (UNCD) Seal Faces Ultrananocrystalline Diamond (UNCD) Seal Faces New Diamond Coatings Reduce Friction and Improve Performance of Mechanical Seals ...

  13. Amorphous diamond films

    DOE Patents [OSTI]

    Falabella, S.

    1998-06-09

    Amorphous diamond films having a significant reduction in intrinsic stress are prepared by biasing a substrate to be coated and depositing carbon ions thereon under controlled temperature conditions. 1 fig.

  14. PROCESS FOR COLORING DIAMONDS

    DOE Patents [OSTI]

    Dugdale, R.A.

    1960-07-19

    A process is given for coloring substantially colorless diamonds in the blue to blue-green range and comprises the steps of irradiating the colorless diamonds with electrons having an energy within the range 0.5 to 2 Mev to obtain an integrated electron flux of between 1 and 2 x 10/sup 18/ thc diamonds may be irradiated 1 hr when they take on a blue color with a slight green tint: After being heated at about 500 deg C for half an hour they become pure blue. Electrons within this energy range contam sufficient energy to displace the diamond atoms from their normal lattice sites into interstitial sites, thereby causing the color changes.

  15. Nitrogen-incorporated ultrananocrystalline diamond microneedle...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Nitrogen-incorporated ultrananocrystalline diamond microneedle arrays for ... Title: Nitrogen-incorporated ultrananocrystalline diamond microneedle arrays for ...

  16. Diamond-graphite field emitters

    DOE Patents [OSTI]

    Valone, Steven M.

    1997-01-01

    A field emission electron emitter comprising an electrode of diamond and a conductive carbon, e.g., graphite, is provided.

  17. Fluidized bed deposition of diamond

    DOE Patents [OSTI]

    Laia, Jr., Joseph R.; Carroll, David W.; Trkula, Mitchell; Anderson, Wallace E.; Valone, Steven M.

    1998-01-01

    A process for coating a substrate with diamond or diamond-like material including maintaining a substrate within a bed of particles capable of being fluidized, the particles having substantially uniform dimensions and the substrate characterized as having different dimensions than the bed particles, fluidizing the bed of particles, and depositing a coating of diamond or diamond-like material upon the substrate by chemical vapor deposition of a carbon-containing precursor gas mixture, the precursor gas mixture introduced into the fluidized bed under conditions resulting in excitation mechanisms sufficient to form the diamond coating.

  18. CVD diamond - fundamental phenomena

    SciTech Connect (OSTI)

    Yarbrough, W.A.

    1993-01-01

    This compilation of figures and diagrams addresses the basic physical processes involved in the chemical vapor deposition of diamond. Different methods of deposition are illustrated. For each method, observations are made of the prominent advantages and disadvantages of the technique. Chemical mechanisms of nucleation are introduced.

  19. DIAMOND AMPLIFIED PHOTOCATHODES.

    SciTech Connect (OSTI)

    SMEDLEY,J.; BEN-ZVI, I.; BOHON, J.; CHANG, X.; GROVER, R.; ISAKOVIC, A.; RAO, T.; WU, Q.

    2007-11-26

    High-average-current linear electron accelerators require photoinjectors capable of delivering tens to hundreds of mA average current, with peak currents of hundreds of amps. Standard photocathodes face significant challenges in meeting these requirements, and often have short operational lifetimes in an accelerator environment. We report on recent progress toward development of secondary emission amplifiers for photocathodes, which are intended to increase the achievable average current while protecting the cathode from the accelerator. The amplifier is a thin diamond wafer which converts energetic (few keV) primary electrons into hundreds of electron-hole pairs via secondary electron emission. The electrons drift through the diamond under an external bias and are emitted into vacuum via a hydrogen-terminated surface with negative electron affinity (NEA). Secondary emission gain of over 200 has been achieved. Two methods of patterning diamond, laser ablation and reactive-ion etching (RIE), are being developed to produce the required geometry. A variety of diagnostic techniques, including FTIR, SEM and AFM, have been used to characterize the diamonds.

  20. Lower pressure synthesis of diamond material

    DOE Patents [OSTI]

    Lueking, Angela; Gutierrez, Humberto; Narayanan, Deepa; Burgess Clifford, Caroline E.; Jain, Puja

    2010-07-13

    Methods of synthesizing a diamond material, particularly nanocrystalline diamond, diamond-like carbon and bucky diamond are provided. In particular embodiments, a composition including a carbon source, such as coal, is subjected to addition of energy, such as high energy reactive milling, producing a milling product enriched in hydrogenated tetrahedral amorphous diamond-like carbon compared to the coal. A milling product is treated with heat, acid and/or base to produce nanocrystalline diamond and/or crystalline diamond-like carbon. Energy is added to produced crystalline diamond-like carbon in particular embodiments to produce bucky diamonds.

  1. Structure and properties of diamond and diamond-like films

    SciTech Connect (OSTI)

    Clausing, R.E.

    1993-01-01

    This section is broken into four parts: (1) introduction, (2) natural IIa diamond, (3) importance of structure and composition, and (4) control of structure and properties. Conclusions of this discussion are that properties of chemical vapor deposited diamond films can compare favorably with natural diamond, that properties are anisotropic and are a strong function of structure and crystal perfection, that crystal perfection and morphology are functions of growth conditions and can be controlled, and that the manipulation of texture and thereby surface morphology and internal crystal perfection is an important step in optimizing chemically deposited diamond films for applications.

  2. Conversion of fullerenes to diamond

    DOE Patents [OSTI]

    Gruen, Dieter M.

    1993-01-01

    A method of forming synthetic diamond on a substrate is disclosed. The method involves providing a substrate surface covered with a fullerene or diamond coating, positioning a fullerene in an ionization source, creating a fullerene vapor, ionizing fullerene molecules, accelerating the fullerene ions to energies above 250 eV to form a fullerene ion beam, impinging the fullerene ion beam on the substrate surface and continuing these steps to obtain a diamond thickness on the substrate.

  3. Conversion of fullerenes to diamond

    DOE Patents [OSTI]

    Gruen, Dieter M.

    1994-01-01

    A method of forming synthetic diamond on a substrate. The method involves providing a substrate surface covered with a fullerene or diamond coating, positioning a fullerene in an ionization source, creating a fullerene vapor, ionizing fullerene molecules, accelerating the fullerene ions to energies above 250 eV to form a fullerene ion beam, impinging the fullerene ion beam on the substrate surface and continuing these steps to obtain a diamond film thickness on the substrate.

  4. Diamond turning of glass

    SciTech Connect (OSTI)

    Blackley, W.S.; Scattergood, R.O.

    1988-12-01

    A new research initiative will be undertaken to investigate the critical cutting depth concepts for single point diamond turning of brittle, amorphous materials. Inorganic glasses and a brittle, thermoset polymer (organic glass) are the principal candidate materials. Interrupted cutting tests similar to those done in earlier research are Ge and Si crystals will be made to obtain critical depth values as a function of machining parameters. The results will provide systematic data with which to assess machining performance on glasses and amorphous materials

  5. Why Physics Needs Diamonds | Department of Energy

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

    Why Physics Needs Diamonds Why Physics Needs Diamonds April 26, 2016 - 3:31pm Addthis A detailed view of the diamond wafers scientists use to get a better measure of spinning electrons. | Photo courtesy of Jefferson Lab. A detailed view of the diamond wafers scientists use to get a better measure of spinning electrons. | Photo courtesy of Jefferson Lab. Kandice Carter Jefferson Lab Diamonds are one of the most coveted gemstones. But while some may want the perfect diamond for its sparkle,

  6. Conversion of fullerenes to diamonds

    DOE Patents [OSTI]

    Gruen, Dieter M.

    1995-01-01

    A method of forming synthetic diamond or diamond-like films on a substrate surface. The method involves the steps of providing a vapor selected from the group of fullerene molecules or an inert gas/fullerene molecule mixture, providing energy to the fullerene molecules consisting of carbon-carbon bonds, the energized fullerene molecules breaking down to form fragments of fullerene molecules including C.sub.2 molecules and depositing the energized fullerene molecules with C.sub.2 fragments onto the substrate with farther fragmentation occurring and forming a thickness of diamond or diamond-like films on the substrate surface.

  7. Fabrication of amorphous diamond films

    DOE Patents [OSTI]

    Falabella, Steven

    1995-01-01

    Amorphous diamond films having a significant reduction in intrinsic stress are prepared by biasing a substrate to be coated and depositing carbon ions thereon under controlled temperature conditions.

  8. Diamond films treated with alkali-halides

    DOE Patents [OSTI]

    Anderson, D.F.; Kwan, S.W.

    1997-04-08

    A secondary electron emitter is provided and includes a substrate with a diamond film, the diamond film is treated or coated with an alkali-halide. 5 figs.

  9. Diamond films treated with alkali-halides

    DOE Patents [OSTI]

    Anderson, David F.; Kwan, Simon W.

    1997-01-01

    A secondary electron emitter is provided and includes a substrate with a diamond film, the diamond film is treated or coated with an alkali-halide.

  10. Blue Diamond Ventures Inc | Open Energy Information

    Open Energy Info (EERE)

    Name: Blue Diamond Ventures Inc Place: Houston,, Texas Zip: 77071 Product: Agriculture, bio fuels and commercial development company. References: Blue Diamond Ventures Inc1 This...

  11. High efficiency diamond solar cells

    DOE Patents [OSTI]

    Gruen, Dieter M.

    2008-05-06

    A photovoltaic device and method of making same. A layer of p-doped microcrystalline diamond is deposited on a layer of n-doped ultrananocrystalline diamond such as by providing a substrate in a chamber, providing a first atmosphere containing about 1% by volume CH.sub.4 and about 99% by volume H.sub.2 with dopant quantities of a boron compound, subjecting the atmosphere to microwave energy to deposit a p-doped microcrystalline diamond layer on the substrate, providing a second atmosphere of about 1% by volume CH.sub.4 and about 89% by volume Ar and about 10% by volume N.sub.2, subjecting the second atmosphere to microwave energy to deposit a n-doped ultrananocrystalline diamond layer on the p-doped microcrystalline diamond layer. Electrodes and leads are added to conduct electrical energy when the layers are irradiated.

  12. Tailoring nanocrystalline diamond film properties

    DOE Patents [OSTI]

    Gruen, Dieter M.; McCauley, Thomas G.; Zhou, Dan; Krauss, Alan R.

    2003-07-15

    A method for controlling the crystallite size and growth rate of plasma-deposited diamond films. A plasma is established at a pressure in excess of about 55 Torr with controlled concentrations of hydrogen up to about 98% by volume, of unsubstituted hydrocarbons up to about 3% by volume and an inert gas of one or more of the noble gases and nitrogen up to about 98% by volume. The volume ratio of inert gas to hydrogen is preferably maintained at greater than about 4, to deposit a diamond film on a suitable substrate. The diamond film is deposited with a predetermined crystallite size and at a predetermined growth rate.

  13. Conversion of fullerenes to diamond

    DOE Patents [OSTI]

    Gruen, Dieter M.

    1994-01-01

    A method of forming synthetic hydrogen defect free diamond or diamond like films on a substrate. The method involves providing vapor containing fullerene molecules with or without an inert gas, providing a device to impart energy to the fullerene molecules, fragmenting at least in part some of the fullerene molecules in the vapor or energizing the molecules to incipient fragmentation, ionizing the fullerene molecules, impinging ionized fullerene molecules on the substrate to assist in causing fullerene fragmentation to obtain a thickness of diamond on the substrate.

  14. New waste-heat refrigeration unit cuts flaring, reduces pollution

    SciTech Connect (OSTI)

    Brant, B.; Brueske, S.; Erickson, D.; Papar, R.

    1998-05-18

    Planetec Utility Services Co. Inc. and Energy Concepts Co. (ECC), with the help of the US Department of Energy (DOE), developed and commissioned a unique waste-heat powered LPG recovery plant in August 1997 at the 30,000 b/d Denver refinery, operated by Ultramar Diamond Shamrock (UDS). This new environmentally friendly technology reduces flare emissions and the loss of salable liquid-petroleum products to the fuel-gas system. The waste heat ammonia absorption refrigeration plant (Whaarp) is the first technology of its kind to use low-temperature waste heat (295 F) to achieve sub-zero refrigeration temperatures ({minus}40 F) with the capability of dual temperature loads in a refinery setting. The ammonia absorption refrigeration is applied to the refinery`s fuel-gas makeup streams to condense over 180 b/d of salable liquid hydrocarbon products. The recovered liquid, about 64,000 bbl/year of LPG and gasoline, increases annual refinery profits by nearly $1 million, while substantially reducing air pollution emissions from the refinery`s flare.

  15. Fabrication of amorphous diamond films

    DOE Patents [OSTI]

    Falabella, S.

    1995-12-12

    Amorphous diamond films having a significant reduction in intrinsic stress are prepared by biasing a substrate to be coated and depositing carbon ions thereon under controlled temperature conditions. 1 fig.

  16. Method of dehalogenation using diamonds

    DOE Patents [OSTI]

    Farcasiu, Malvina (Roslyn Harbor, NY); Kaufman, Phillip B. (Lafayette, LA); Ladner, Edward P. (Pittsburgh, PA); Anderson, Richard R. (Brownsville, PA)

    2000-01-01

    A method for preparing olefins and halogenated olefins is provided comprising contacting halogenated compounds with diamonds for a sufficient time and at a sufficient temperature to convert the halogenated compounds to olefins and halogenated olefins via elimination reactions.

  17. Amorphous-diamond electron emitter

    DOE Patents [OSTI]

    Falabella, Steven

    2001-01-01

    An electron emitter comprising a textured silicon wafer overcoated with a thin (200 .ANG.) layer of nitrogen-doped, amorphous-diamond (a:D-N), which lowers the field below 20 volts/micrometer have been demonstrated using this emitter compared to uncoated or diamond coated emitters wherein the emission is at fields of nearly 60 volts/micrometer. The silicon/nitrogen-doped, amorphous-diamond (Si/a:D-N) emitter may be produced by overcoating a textured silicon wafer with amorphous-diamond (a:D) in a nitrogen atmosphere using a filtered cathodic-arc system. The enhanced performance of the Si/a:D-N emitter lowers the voltages required to the point where field-emission displays are practical. Thus, this emitter can be used, for example, in flat-panel emission displays (FEDs), and cold-cathode vacuum electronics.

  18. Double bevel construction of a diamond anvil

    DOE Patents [OSTI]

    Moss, W.C.

    1987-02-06

    Use of double or multiple bevel culet geometry on a diamond anvil to provide increased sample pressure and stability for a given force applied to the diamond tables. 7 figs.

  19. Method of Forming Diamonds from Carbonaceous Material

    SciTech Connect (OSTI)

    Daulton, Tyrone; Lewis, Roy; Rehn, Lynn; Kirk, Marquis

    1999-11-30

    A method for producing diamonds is provided comprising exposing carbonaceous material to ion irradiation at ambient temperature and pressure.

  20. Method for forming diamonds from carbonaceous material

    DOE Patents [OSTI]

    Daulton, Tyrone; Lewis, Roy; Rehn, Lynn; Kirk, Marquis

    2001-01-01

    A method for producing diamonds is provided comprising exposing carbonaceous material to ion irradiation at ambient temperature and pressure.

  1. Diamond and diamond-like films for transportation applications

    SciTech Connect (OSTI)

    Perez, J.M.

    1993-01-01

    This section is a compilation of transparency templates which describe the goals of the Office of Transportation Materials (OTM) Tribology Program. The positions of personnel on the OTM are listed. The role and mission of the OTM is reviewed. The purpose of the Tribology Program is stated to be `to obtain industry input on program(s) in tribology/advanced lubricants areas of interest`. The objective addressed here is to identify opportunities for cost effective application of diamond and diamond-like carbon in transportation systems.

  2. Characterization of single-crystal diamond grown from the vapor phase on substrates of natural diamond

    SciTech Connect (OSTI)

    Altukhov, A. A.; Vikharev, A. L.; Gorbachev, A. M.; Dukhnovsky, M. P.; Zemlyakov, V. E.; Ziablyuk, K. N.; Mitenkin, A. V.; Muchnikov, A. B. Radishev, D. B.; Ratnikova, A. K.; Fedorov, Yu. Yu.

    2011-03-15

    The results of studies of single-crystal diamond layers with orientation (100) grown on substrates of IIa-type natural diamond by chemical-vapor deposition and of semiconductor diamond obtained subsequently by doping by implantation of boron ions are reported. Optimal conditions of postimplantation annealing of diamond that provide the hole mobility of 1150 cm{sup 2} V{sup -1} s{sup -1} (the highest mobility obtained so far for semiconductor diamond after ion implantation) are given.

  3. Ultratough single crystal boron-doped diamond

    DOE Patents [OSTI]

    Hemley, Russell J [Carnegie Inst. for Science, Washington, DC ; Mao, Ho-Kwang [Carnegie Inst. for Science, Washington, DC ; Yan, Chih-Shiue [Carnegie Inst. for Science, Washington, DC ; Liang, Qi [Carnegie Inst. for Science, Washington, DC

    2015-05-05

    The invention relates to a single crystal boron doped CVD diamond that has a toughness of at least about 22 MPa m.sup.1/2. The invention further relates to a method of manufacturing single crystal boron doped CVD diamond. The growth rate of the diamond can be from about 20-100 .mu.m/h.

  4. Diamond-silicon carbide composite

    DOE Patents [OSTI]

    Qian, Jiang; Zhao, Yusheng

    2006-06-13

    Fully dense, diamond-silicon carbide composites are prepared from ball-milled microcrystalline diamond/amorphous silicon powder mixture. The ball-milled powder is sintered (P=5–8 GPa, T=1400K–2300K) to form composites having high fracture toughness. A composite made at 5 GPa/1673K had a measured fracture toughness of 12 MPa.dot.m1/2. By contrast, liquid infiltration of silicon into diamond powder at 5 GPa/1673K produces a composite with higher hardness but lower fracture toughness. X-ray diffraction patterns and Raman spectra indicate that amorphous silicon is partially transformed into nanocrystalline silicon at 5 GPa/873K, and nanocrystalline silicon carbide forms at higher temperatures.

  5. Diamond-silicon carbide composite

    DOE Patents [OSTI]

    Qian, Jiang; Zhao, Yusheng

    2006-06-13

    Fully dense, diamond-silicon carbide composites are prepared from ball-milled microcrystalline diamond/amorphous silicon powder mixture. The ball-milled powder is sintered (P=5–8 GPa, T=1400K–2300K) to form composites having high fracture toughness. A composite made at 5 GPa/1673K had a measured fracture toughness of 12 MPa.dot.m1/2. By contrast, liquid infiltration of silicon into diamond powder at 5 GPa/1673K produces a composite with higher hardness but lower fracture toughness. X-ray diffraction patterns and Raman spectra indicate that amorphous silicon is partially transformed into nanocrystalline silicon at 5 GPa/873K, and nanocrystalline silicon carbide forms at higher temperatures.

  6. Method for machining steel with diamond tools

    DOE Patents [OSTI]

    Casstevens, J.M.

    1984-01-01

    The present invention is directed to a method for machine optical quality finishes and contour accuracies of workpieces of carbon-containing metals such as steel with diamond tooling. The wear rate of the diamond tooling is significantly reduced by saturating the atmosphere at the interface of the workpiece and the diamond tool with a gaseous hydrocarbon during the machining operation. The presence of the gaseous hydrocarbon effectively eliminates the deterioration of the diamond tool by inhibiting or preventing the conversion of the diamond carbon to graphite carbon at the point of contact between the cutting tool and the workpiece.

  7. Method for machining steel with diamond tools

    DOE Patents [OSTI]

    Casstevens, John M.

    1986-01-01

    The present invention is directed to a method for machining optical quality inishes and contour accuracies of workpieces of carbon-containing metals such as steel with diamond tooling. The wear rate of the diamond tooling is significantly reduced by saturating the atmosphere at the interface of the workpiece and the diamond tool with a gaseous hydrocarbon during the machining operation. The presence of the gaseous hydrocarbon effectively eliminates the deterioration of the diamond tool by inhibiting or preventing the conversion of the diamond carbon to graphite carbon at the point of contact between the cutting tool and the workpiece.

  8. Saturation of CVD Diamond Detectors

    SciTech Connect (OSTI)

    Lucile S. Dauffy; Richard A. Lerche; Greg J. Schmid; Jeffrey A. Koch; Christopher Silbernagel

    2005-01-01

    A 5 x 0.25 mm Chemical Vapor Deposited (CVD) diamond detector, with a voltage bias of + 250V, was excited by a 400 nm laser (3.1 eV photons) in order to study the saturation of the wafer and its surrounding electronics. In a first experiment, the laser beam energy was increased from a few tens of a pJ to about 100 µJ, and the signal from the diamond was recorded until full saturation of the detection system was achieved. Clear saturation of the detection system was observed at about 40 V, which corresponds with the expected saturation at 10% of the applied bias (250V). The results indicate that the interaction mechanism of the 3.1 eV photons in the diamond (Ebandgap = 5.45 eV) is not a multi-photon process but is linked to the impurities and defects of the crystal. In a second experiment, the detector was irradiated by a saturating first laser pulse and then by a delayed laser pulse of equal or smaller amplitude with delays of 5, 10, and 20 ns. The results suggest that the diamond and associated electronics recover within 10 to 20 ns after a strong saturating pulse.

  9. EA-1795: Diamond Green Diesel Facility in Norco, LA | Department...

    Energy Savers [EERE]

    5: Diamond Green Diesel Facility in Norco, LA EA-1795: Diamond Green Diesel Facility in Norco, LA April 1, 2011 EA-1795: Final Environmental Assessment Loan Guarantee to Diamond ...

  10. Diamond turning machine controller implementation

    SciTech Connect (OSTI)

    Garrard, K.P.; Taylor, L.W.; Knight, B.F.; Fornaro, R.J.

    1988-12-01

    The standard controller for a Pnuemo ASG 2500 Diamond Turning Machine, an Allen Bradley 8200, has been replaced with a custom high-performance design. This controller consists of four major components. Axis position feedback information is provided by a Zygo Axiom 2/20 laser interferometer with 0.1 micro-inch resolution. Hardware interface logic couples the computers digital and analog I/O channels to the diamond turning machine`s analog motor controllers, the laser interferometer, and other machine status and control information. It also provides front panel switches for operator override of the computer controller and implement the emergency stop sequence. The remaining two components, the control computer hardware and software, are discussed in detail below.

  11. Diamond-silicon carbide composite and method

    DOE Patents [OSTI]

    Zhao, Yusheng

    2011-06-14

    Uniformly dense, diamond-silicon carbide composites having high hardness, high fracture toughness, and high thermal stability are prepared by consolidating a powder mixture of diamond and amorphous silicon. A composite made at 5 GPa/1673K had a measured fracture toughness of 12 MPam.sup.1/2. By contrast, liquid infiltration of silicon into diamond powder at 5 GPa/1673K produces a composite with higher hardness but lower fracture toughness.

  12. Bruce Diamond | National Nuclear Security Administration | (NNSA)

    National Nuclear Security Administration (NNSA)

    Bruce Diamond General Counsel Bruce Diamond Bruce Diamond became the General Counsel for the NNSA in February, 2011. Before that, Bruce was DOE Assistant General Counsel for Environment, the senior career environmental attorney for the Department dealing principally with complex issues regarding the clean-up of the nuclear complex and implementation of National Environmental Policy Act obligations. In addition, he was responsible for addressing health and safety issues. Previously, he was a

  13. Diamond turning of thermoplastic polymers

    SciTech Connect (OSTI)

    Smith, E.; Scattergood, R.O.

    1988-12-01

    Single point diamond turning studies were made using a series of thermoplastic polymers with different glass transition temperatures. Variations in surface morphology and surface roughness were observed as a function of cutting speed. Lower glass transition temperatures facilitate smoother surface cuts and better surface finish. This can be attributed to the frictional heating that occurs during machining. Because of the very low glass transition temperatures in polymeric compared to inorganic glasses, the precision machining response can be very speed sensitive.

  14. Diamond Energy Pty Ltd | Open Energy Information

    Open Energy Info (EERE)

    Pty Ltd Jump to: navigation, search Name: Diamond Energy Pty Ltd Place: Melbourne, Australia Zip: 3124 Product: Victoria based clean energy project developer. Coordinates:...

  15. Diamond Walnut Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    NEEDS 2006 Database Retrieved from "http:en.openei.orgwindex.php?titleDiamondWalnutBiomassFacility&oldid397401" Feedback Contact needs updating Image needs updating...

  16. Superconducting nanowire single photon detector on diamond

    SciTech Connect (OSTI)

    Atikian, Haig A.; Burek, Michael J.; Choy, Jennifer T.; Lon?ar, Marko; Eftekharian, Amin; Jafari Salim, A.; Hamed Majedi, A.

    2014-03-24

    Superconducting nanowire single photon detectors are fabricated directly on diamond substrates and their optical and electrical properties are characterized. Dark count performance and photon count rates are measured at varying temperatures for 1310?nm and 632?nm photons. A multi-step diamond surface polishing procedure is reported, involving iterative reactive ion etching and mechanical polishing to create a suitable diamond surface for the deposition and patterning of thin film superconducting layers. Using this approach, diamond substrates with less than 300?pm Root Mean Square surface roughness are obtained.

  17. Diamond Wire Technology LLC | Open Energy Information

    Open Energy Info (EERE)

    Wire Technology LLC Jump to: navigation, search Name: Diamond Wire Technology LLC Place: Colorado Springs, Colorado Zip: 80916 Sector: Solar Product: US-based manufacturer of...

  18. Modeling electron emission and surface effects from diamond cathodes...

    Office of Scientific and Technical Information (OSTI)

    and surface effects from diamond cathodes Citation Details In-Document Search Title: Modeling electron emission and surface effects from diamond cathodes Authors: Dimitrov D. ...

  19. All diamond self-aligned thin film transistor

    DOE Patents [OSTI]

    Gerbi, Jennifer

    2008-07-01

    A substantially all diamond transistor with an electrically insulating substrate, an electrically conductive diamond layer on the substrate, and a source and a drain contact on the electrically conductive diamond layer. An electrically insulating diamond layer is in contact with the electrically conductive diamond layer, and a gate contact is on the electrically insulating diamond layer. The diamond layers may be homoepitaxial, polycrystalline, nanocrystalline or ultrananocrystalline in various combinations.A method of making a substantially all diamond self-aligned gate transistor is disclosed in which seeding and patterning can be avoided or minimized, if desired.

  20. Diamond film growth argon-carbon plasmas

    DOE Patents [OSTI]

    Gruen, Dieter M.; Krauss, Alan R.; Liu, Shengzhong; Pan, Xianzheng; Zuiker, Christopher D.

    1998-01-01

    A method and system for manufacturing diamond film. The method involves forming a carbonaceous vapor, providing a gas stream of argon, hydrogen and hydrocarbon and combining the gas with the carbonaceous vapor, passing the combined carbonaceous vapor and gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the carbonaceous and deposition of a diamond film on a substrate.

  1. Diamond film growth from fullerene precursors

    DOE Patents [OSTI]

    Gruen, Dieter M.; Liu, Shengzhong; Krauss, Alan R.; Pan, Xianzheng

    1997-01-01

    A method and system for manufacturing diamond film. The method involves forming a fullerene vapor, providing a noble gas stream and combining the gas with the fullerene vapor, passing the combined fullerene vapor and noble gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the fullerene and deposition of a diamond film on a substrate.

  2. Fluorinated diamond bonded in fluorocarbon resin

    DOE Patents [OSTI]

    Taylor, Gene W.

    1982-01-01

    By fluorinating diamond grit, the grit may be readily bonded into a fluorocarbon resin matrix. The matrix is formed by simple hot pressing techniques. Diamond grinding wheels may advantageously be manufactured using such a matrix. Teflon fluorocarbon resins are particularly well suited for using in forming the matrix.

  3. Double bevel construction of a diamond anvil

    DOE Patents [OSTI]

    Moss, William C.

    1988-01-01

    A double or multiple bevel culet geometry is used on a diamond anvil in a high pressure cell apparatus to provide increased sample pressure and stability for a given force applied to the diamond tables. Double or multiple bevel culet geometries can also be used for sapphire or other hard crystal anvils. Pressures up to and above 5 Megabars can be reached.

  4. Double bevel construction of a diamond anvil

    DOE Patents [OSTI]

    Moss, W.C.

    1988-10-11

    A double or multiple bevel culet geometry is used on a diamond anvil in a high pressure cell apparatus to provide increased sample pressure and stability for a given force applied to the diamond tables. Double or multiple bevel culet geometries can also be used for sapphire or other hard crystal anvils. Pressures up to and above 5 Megabars can be reached. 8 figs.

  5. Microstructure and thermal properties of copper–diamond composites with tungsten carbide coating on diamond particles

    SciTech Connect (OSTI)

    Kang, Qiping; He, Xinbo Ren, Shubin; Liu, Tingting; Liu, Qian; Wu, Mao; Qu, Xuanhui

    2015-07-15

    An effective method for preparing tungsten carbide coating on diamond surfaces was proposed to improve the interface bonding between diamond and copper. The WC coating was formed on the diamond surfaces with a reaction medium of WO{sub 3} in mixed molten NaCl–KCl salts and the copper–diamond composites were obtained by vacuum pressure infiltration of WC-coated diamond particles with pure copper. The microstructure of interface bonding between diamond and copper was discussed. Thermal conductivity and thermal expansion behavior of the obtained copper–diamond composites were investigated. Results indicated that the thermal conductivity of as-fabricated composite reached 658 W m{sup −} {sup 1} K{sup −} {sup 1}. Significant reduction in coefficient of thermal expansion of the composite compared with that of pure copper was obtained. - Highlights: • WC coating was successfully synthesized on diamond particles in molten salts. • WC coating obviously promoted the wettability of diamond and copper matrix. • WC coating greatly enhanced the thermal conductivity of Cu–diamond composite. • The composites are suitable candidates for heat sink applications.

  6. Self-composite comprised of nanocrystalline diamond and a non-diamond component useful for thermoelectric applications

    DOE Patents [OSTI]

    Gruen, Dieter M.

    2012-09-04

    One provides nanocrystalline diamond material that comprises a plurality of substantially ordered diamond crystallites that are sized no larger than about 10 nanometers. One then disposes a non-diamond component within the nanocrystalline diamond material. By one approach this non-diamond component comprises an electrical conductor that is formed at the grain boundaries that separate the diamond crystallites from one another. The resultant nanowire is then able to exhibit a desired increase with respect to its ability to conduct electricity while also preserving the thermal conductivity behavior of the nanocrystalline diamond material.

  7. Self-composite comprised of nanocrystalline diamond and a non-diamond component useful for thermoelectric applications

    DOE Patents [OSTI]

    Gruen, Dieter M.

    2009-08-11

    One provides nanocrystalline diamond material that comprises a plurality of substantially ordered diamond crystallites that are sized no larger than about 10 nanometers. One then disposes a non-diamond component within the nanocrystalline diamond material. By one approach this non-diamond component comprises an electrical conductor that is formed at the grain boundaries that separate the diamond crystallites from one another. The resultant nanowire is then able to exhibit a desired increase with respect to its ability to conduct electricity while also preserving the thermal conductivity behavior of the nanocrystalline diamond material.

  8. Multifrequency spin resonance in diamond

    SciTech Connect (OSTI)

    Childress, Lilian; McIntyre, Jean

    2010-09-15

    Magnetic resonance techniques provide a powerful tool for controlling spin systems, with applications ranging from quantum information processing to medical imaging. Nevertheless, the behavior of a spin system under strong excitation remains a rich dynamical problem. In this paper, we examine spin resonance of the nitrogen-vacancy center in diamond under conditions outside the regime where the usual rotating-wave approximation applies, focusing on effects of multifrequency excitation and excitation with orientation parallel to the spin quantization axis. Strong-field phenomena such as multiphoton transitions and coherent destruction of tunneling are observed in the spectra and analyzed via numerical and analytic theory. In addition to illustrating the response of a spin system to strong multifrequency excitation, these observations may inform techniques for manipulating electron-nuclear spin quantum registers.

  9. Diamond coated silicon field emitter array

    SciTech Connect (OSTI)

    S. Albin; W. Fu; A. Varghese; A. C. Lavarias; G. R. Myneni

    1999-07-01

    Diamond coated silicon tip arrays, with and without a self-aligned gate, were fabricated, and current-voltage characteristics of 400 tips were measured. Diamond films were grown uniformly on Si tips using microwave plasma after nucleation with 10 nm diamond suspension and substrate bias. An emission current of 57 ?A was obtained at 5 V from the ungated array tips separated from an anode at 2 ?m. In the case of the gated arrays with 1.5 ?m aperture, an emission current of 3.4 ?A was measured at a gate voltage of 80 V for an anode separation of 200 ?m. The turn-on voltages for these two types of devices were 0.2 and 40 V, respectively. Diamond coated Si tip arrays have potential applications in field emission based low voltage vacuum electronic devices and microsensors.

  10. Diamond film growth argon-carbon plasmas

    DOE Patents [OSTI]

    Gruen, D.M.; Krauss, A.R.; Liu, S.Z.; Pan, X.Z.; Zuiker, C.D.

    1998-12-15

    A method and system are disclosed for manufacturing diamond film. The method involves forming a carbonaceous vapor, providing a gas stream of argon, hydrogen and hydrocarbon and combining the gas with the carbonaceous vapor, passing the combined carbonaceous vapor and gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the carbonaceous and deposition of a diamond film on a substrate. 29 figs.

  11. Diamond film growth from fullerene precursors

    DOE Patents [OSTI]

    Gruen, D.M.; Liu, S.; Krauss, A.R.; Pan, X.

    1997-04-15

    A method and system are disclosed for manufacturing diamond film. The method involves forming a fullerene vapor, providing a noble gas stream and combining the gas with the fullerene vapor, passing the combined fullerene vapor and noble gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the fullerene and deposition of a diamond film on a substrate. 10 figs.

  12. Getting a better measure of spin with diamond | Jefferson Lab

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

    Getting a better measure of spin with diamond Diamond detector The Hall C Compton Polarimeter uses a novel detector system built of thin slivers of diamond, seen here. The lab-grown slices of diamond, measuring roughly three-quarters of an inch square (2 cm) and a mere two hundredths of an inch thick, are outfitted like computer chips, with 96 tiny electrodes stuck to them. The electrodes send a signal when the diamond detector counts an electron. Getting a better measure of spin with diamond

  13. Plasma spraying method for forming diamond and diamond-like coatings

    DOE Patents [OSTI]

    Holcombe, Cressie E.; Seals, Roland D.; Price, R. Eugene

    1997-01-01

    A method and composition for the deposition of a thick layer (10) of diamond or diamond-like material. The method includes high temperature processing wherein a selected composition (12) including at least glassy carbon is heated in a direct current plasma arc device to a selected temperature above the softening point, in an inert atmosphere, and is propelled to quickly quenched on a selected substrate (20). The softened or molten composition (18) crystallizes on the substrate (20) to form a thick deposition layer (10) comprising at least a diamond or diamond-like material. The selected composition (12) includes at least glassy carbon as a primary constituent (14) and may include at least one secondary constituent (16). Preferably, the secondary constituents (16) are selected from the group consisting of at least diamond powder, boron carbide (B.sub.4 C) powder and mixtures thereof.

  14. Plasma spraying method for forming diamond and diamond-like coatings

    DOE Patents [OSTI]

    Holcombe, C.E.; Seals, R.D.; Price, R.E.

    1997-06-03

    A method and composition is disclosed for the deposition of a thick layer of diamond or diamond-like material. The method includes high temperature processing wherein a selected composition including at least glassy carbon is heated in a direct current plasma arc device to a selected temperature above the softening point, in an inert atmosphere, and is propelled to quickly quenched on a selected substrate. The softened or molten composition crystallizes on the substrate to form a thick deposition layer comprising at least a diamond or diamond-like material. The selected composition includes at least glassy carbon as a primary constituent and may include at least one secondary constituent. Preferably, the secondary constituents are selected from the group consisting of at least diamond powder, boron carbide (B{sub 4}C) powder and mixtures thereof. 9 figs.

  15. n-Type diamond and method for producing same

    DOE Patents [OSTI]

    Anderson, Richard J.

    2002-01-01

    A new n-type semiconducting diamond is disclosed, which is doped with n-type dopant atoms. Such diamond is advantageously formed by chemical vapor deposition from a source gas mixture comprising a carbon source compound for the diamond, and a volatile hot wire filament for the n-type impurity species, so that the n-type impurity atoms are doped in the diamond during its formation. A corresponding chemical vapor deposition method of forming the n-type semiconducting diamond is disclosed. The n-type semiconducting diamond of the invention may be usefully employed in the formation of diamond-based transistor devices comprising pn diamond junctions, and in other microelectronic device applications.

  16. Comparative evaluation of CVD diamond technologies

    SciTech Connect (OSTI)

    Anthony, T.R.

    1993-01-01

    Chemical vapor deposition (CVD) of diamonds occurs from hydrogen-hydrocarbon gas mixtures in the presence of atomic hydrogen at subatmospheric pressures. Most CVD methods are based on different means of generating and transporting atomic hydrogen in a particular system. Evaluation of these different techniques involves their capital costs, material costs, energy costs, labor costs and the type and quality of diamond that they produce. Currently, there is no universal agreement on which is the best technique and technique selection has been largely driven by the professional background of the user as well as the particular application of interest. This article discusses the criteria for evaluating a process for low-pressure deposition of diamond. Next, a brief history of low-pressure diamond synthesis is reviewed. Several specific processes are addressed, including the hot filament process, hot filament electron-assisted chemical vapor deposition, and plasma generation of atomic hydrogen by glow discharge, microwave discharge, low pressure radio frequency discharge, high pressure DC discharge, high pressure microwave discharge jets, high pressure RF discharge, and high and low pressure flames. Other types of diamond deposition methods are also evaluated. 101 refs., 15 figs.

  17. Study of Electron Transport and Amplification in Diamond

    SciTech Connect (OSTI)

    Muller, Erik M.; Ben-Zvi, Ilan

    2013-03-31

    As a successful completion of this award, my group has demonstrated world-leading electron gain from diamond for use in a diamond-amplified photocathode. Also, using high-resolution photoemission measurements we were able to uncover exciting new physics of the electron emission mechanisms from hydrogen terminated diamond. Our work, through the continued support of HEP, has resulted in a greater understanding of the diamond material science, including current limits, charge transport modeling, and spatial uniformity.

  18. First principles study of Fe in diamond: A diamond-based half metallic dilute magnetic semiconductor

    SciTech Connect (OSTI)

    Benecha, E. M.; Lombardi, E. B.

    2013-12-14

    Half-metallic ferromagnetic ordering in semiconductors, essential in the emerging field of spintronics for injection and transport of highly spin polarised currents, has up to now been considered mainly in III–V and II–VI materials. However, low Curie temperatures have limited implementation in room temperature device applications. We report ab initio Density Functional Theory calculations on the properties of Fe in diamond, considering the effects of lattice site, charge state, and Fermi level position. We show that the lattice sites and induced magnetic moments of Fe in diamond depend strongly on the Fermi level position and type of diamond co-doping, with Fe being energetically most favorable at the substitutional site in p-type and intrinsic diamond, while it is most stable at a divacancy site in n-type diamond. Fe induces spin polarized bands in the band gap, with strong hybridization between Fe-3d and C-2s,2p bands. We further consider Fe-Fe spin interactions in diamond and show that substitutional Fe{sup +1} in p-type diamond exhibits a half-metallic character, with a magnetic moment of 1.0 μ{sub B} per Fe atom and a large ferromagnetic stabilization energy of 33 meV, an order of magnitude larger than in other semiconductors, with correspondingly high Curie temperatures. These results, combined with diamond's unique properties, demonstrate that Fe doped p-type diamond is likely to be a highly suitable candidate material for spintronics applications.

  19. Vacancy induced structural changes in diamond.

    SciTech Connect (OSTI)

    Barnard, A.; Sternberg, M.; Univ. of Melbourne

    2008-01-01

    Although optically active defects in nanodiamond are being considered as candidates for optical labeling in biomedical applications, development in this area is being hindered the fact that suitable defects are rarely seen in diamond nanoparticles in the size regime required. These defects usually form as a complex with an impurity and a neutral of charged vacancy, so a measurable concentration of vacancy point defects is also necessary. Presented here are results of density functional tight binding computer simulations investigating the stability of vacancies in diamond nanoparticles with different surface structures. The results indicate that both neutral and charged vacancies alter the structure of as-grown diamond nanoparticles and are likely to diffuse out of the particle during synthesis or irradiation. We also find that suitable passivation of the particle may alleviate this problem, and hence facilitate the formation of defect complexes.

  20. STATUS OF DIAMOND SECONDARY EMISSION ENHANCED PHOTOCATHODE

    SciTech Connect (OSTI)

    RAO,T.; BEN-ZVI, I.; CHANG, X.; GRIMES, J.; GROVER, R.; ISAKOVIC, A.; SMEDLEY, J.; TODD, R.; WARREN, J.; WU, Q.

    2007-05-25

    The diamond secondary emission enhanced photocathode (SEEP) provides an attractive alternative for simple photo cathodes in high average current electron injectors. It reduces the laser power required to drive the cathode, simultaneously isolating the cathode and the FW cavity from each other, thereby protecting them from contamination and increasing their life time. In this paper, we present the latest results on the secondary electron yield using pulsed thermionic and photo cathodes as primary electron sources, shaping the diamond using laser ablation and reactive ion etching as well as the theoretical underpinning of secondary electron generation and preliminary results of modeling.

  1. Method of improving field emission characteristics of diamond thin films

    DOE Patents [OSTI]

    Krauss, A.R.; Gruen, D.M.

    1999-05-11

    A method of preparing diamond thin films with improved field emission properties is disclosed. The method includes preparing a diamond thin film on a substrate, such as Mo, W, Si and Ni. An atmosphere of hydrogen (molecular or atomic) can be provided above the already deposited film to form absorbed hydrogen to reduce the work function and enhance field emission properties of the diamond film. In addition, hydrogen can be absorbed on intergranular surfaces to enhance electrical conductivity of the diamond film. The treated diamond film can be part of a microtip array in a flat panel display. 3 figs.

  2. Method of improving field emission characteristics of diamond thin films

    DOE Patents [OSTI]

    Krauss, Alan R.; Gruen, Dieter M.

    1999-01-01

    A method of preparing diamond thin films with improved field emission properties. The method includes preparing a diamond thin film on a substrate, such as Mo, W, Si and Ni. An atmosphere of hydrogen (molecular or atomic) can be provided above the already deposited film to form absorbed hydrogen to reduce the work function and enhance field emission properties of the diamond film. In addition, hydrogen can be absorbed on intergranular surfaces to enhance electrical conductivity of the diamond film. The treated diamond film can be part of a microtip array in a flat panel display.

  3. Diamond Shaving of Contaminated Concrete Surfaces

    SciTech Connect (OSTI)

    Mullen, Lisa K.

    2008-01-15

    Decommissioning and decontamination of existing facilities presents technological challenges. One major challenge is the removal of surface contamination from concrete floors and walls while eliminating the spread of contamination and volumetric reduction of the waste stream. Numerous methods have been tried with a varying degree of success. Recent technology has made this goal achievable and has been used successfully. This new technology is the Diamond Floor Shaver and Diamond Wall shaver. The Diamond Floor Shaver is a self-propelled, walk behind machine that literally shaves the contaminated concrete surface to specified depths. This is accomplished by using a patented system of 100 dry cutting diamond blades with offset diamond segments that interlock to provide complete shaving of the concrete surface. Grooves are eliminated which allows for a direct frisk reading to analyze results. When attached to an appropriate size vacuum, the dust produced is 100% contained. Dust is collected in drums ready for disposition and disposal. The waste produced in shaving 7,500 square feet at 1/8 inch thickness would fill a single 55 gallon drum. Production is dependent on depth of shaving but averages 100 square feet per hour. The wall shaver uses the same patented diamond drum and blades but is hydraulically driven and is deployed using a robotic arm allowing its operation to be to totally remote. It can reach ceilings as high as 20 feet. Numerous small projects were successfully completed using this technology. Large scale deployment came in 2003. Bluegrass, in conjunction with Bartlett Services, deployed this technology to support decontamination activities for closing of the Rocky Flats nuclear weapons site. Up to six floor shavers and one wall shaver were deployed in buildings B371 and B374. These buildings had up to one half-inch, fixed plutonium and beryllium contamination. Hundred-thousands of square feet of floors and walls were shaved successfully to depths of up to

  4. Workshop on diamond and diamond-like-carbon films for the transportation industry

    SciTech Connect (OSTI)

    Nichols, F.A.; Moores, D.K.

    1993-01-01

    Applications exist in advanced transportation systems as well as in manufacturing processes that would benefit from superior tribological properties of diamond, diamond-like-carbon and cubic boron nitride coatings. Their superior hardness make them ideal candidates as protective coatings to reduce adhesive, abrasive and erosive wear in advanced diesel engines, gas turbines and spark-ignited engines and in machining and manufacturing tools as well. The high thermal conductivity of diamond also makes it desirable for thermal management not only in tribological applications but also in high-power electronic devices and possibly large braking systems. A workshop has been recently held at Argonne National Laboratory entitled ``Diamond and Diamond-Like-Carbon Films for Transportation Applications`` which was attended by 85 scientists and engineers including top people involved in the basic technology of these films and also representatives from many US industrial companies. A working group on applications endorsed 18 different applications for these films in the transportation area alone. Separate abstracts have been prepared.

  5. Stability of polarized states for diamond valleytronics

    SciTech Connect (OSTI)

    Hammersberg, J.; Majdi, S.; Kovi, K. K.; Suntornwipat, N.; Gabrysch, M.; Isberg, J.; Twitchen, D. J.

    2014-06-09

    The stability of valley polarized electron states is crucial for the development of valleytronics. A long relaxation time of the valley polarization is required to enable operations to be performed on the polarized states. Here, we investigate the stability of valley polarized states in diamond, expressed as relaxation time. We have found that the stability of the states can be extremely long when we consider the electron-phonon scattering processes allowed by symmetry considerations. We determine electron-phonon coupling constants by Time-of-Flight measurements and Monte Carlo simulations and use these data to map out the relaxation time temperature dependency. The relaxation time for diamond can be microseconds or longer below 100 K and 100 V/cm due to the strong covalent bond, which is highly encouraging for future use in valleytronic applications.

  6. Methane storage capabilities of diamond analogues

    SciTech Connect (OSTI)

    Haranczyk, M; Lin, LC; Lee, K; Martin, RL; Neaton, JB; Smit, B

    2013-01-01

    Methane can be an alternative fuel for vehicular usage provided that new porous materials are developed for its efficient adsorption-based storage. Herein, we search for materials for this application within the family of diamond analogues. We used density functional theory to investigate structures in which tetrahedral C atoms of diamond are separated by-CC-or-BN-groups, as well as ones involving substitution of tetrahedral C atoms with Si and Ge atoms. The adsorptive and diffusive properties of methane are studied using classical molecular simulations. Our results suggest that the all-carbon structure has the highest volumetric methane uptake of 280 VSTP/V at p = 35 bar and T = 298 K. However, it suffers from limited methane diffusion. Alternatively, the considered Si and Ge-containing analogies have fast diffusive properties but their adsorption is lower, ca. 172-179 VSTP/V, at the same conditions.

  7. Measurement of tool forces in diamond turning

    SciTech Connect (OSTI)

    Drescher, J.; Dow, T.A.

    1988-12-01

    A dynamometer has been designed and built to measure forces in diamond turning. The design includes a 3-component, piezoelectric transducer. Initial experiments with this dynamometer system included verification of its predicted dynamic characteristics as well as a detailed study of cutting parameters. Many cutting experiments have been conducted on OFHC Copper and 6061-T6 Aluminum. Tests have involved investigation of velocity effects, and the effects of depth and feedrate on tool forces. Velocity has been determined to have negligible effects between 4 and 21 m/s. Forces generally increase with increasing depth of cut. Increasing feedrate does not necessarily lead to higher forces. Results suggest that a simple model may not be sufficient to describe the forces produced in the diamond turning process.

  8. Precision diamond grinding of ceramics and glass

    SciTech Connect (OSTI)

    Smith, S.; Paul, H.; Scattergood, R.O.

    1988-12-01

    A new research initiative will be undertaken to investigate the effect of machine parameters and material properties on precision diamond grinding of ceramics and glass. The critical grinding depth to initiate the plastic flow-to-brittle fracture regime will be directly measured using plunge-grind tests. This information will be correlated with machine parameters such as wheel bonding and diamond grain size. Multiaxis grinding tests will then be made to provide data more closely coupled with production technology. One important aspect of the material property studies involves measuring fracture toughness at the very short crack sizes commensurate with grinding damage. Short crack toughness value`s can be much less than the long-crack toughness values measured in conventional fracture tests.

  9. Method to fabricate micro and nano diamond devices

    DOE Patents [OSTI]

    Morales, Alfredo M; Anderson, Richard J; Yang, Nancy Y. C.; Skinner, Jack L; Rye, Michael J

    2014-10-07

    A method including forming a diamond material on the surface of a substrate; forming a first contact and a separate second contact; and patterning the diamond material to form a nanowire between the first contact and the second contact. An apparatus including a first contact and a separate second contact on a substrate; and a nanowire including a single crystalline or polycrystalline diamond material on the substrate and connected to each of the first contact and the second contact.

  10. Argonne researchers develop two new diamond inventions | Argonne National

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

    Laboratory researchers develop two new diamond inventions By Jared Sagoff * October 10, 2014 Tweet EmailPrint ARGONNE, IL - Researchers at the US Department of Energy's Argonne National Laboratory have continued their research into advanced ultrananocrystalline diamond technologies and have developed two new applications for this special material. Ultrananocrystalline diamond (UNCD) thin films have shown a great deal of promise in the semiconductor and microelectromechanical systems (MEMS)

  11. EA-1795: Diamond Green Diesel Facility in Norco, LA | Department of Energy

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

    5: Diamond Green Diesel Facility in Norco, LA EA-1795: Diamond Green Diesel Facility in Norco, LA April 1, 2011 EA-1795: Final Environmental Assessment Loan Guarantee to Diamond Green Diesel, LLC for Construction of the Diamond Green Diesel Facility in Norco, Louisiana April 18, 2011 EA-1795: Finding of No Significant Impact Loan Guarantee to Diamond Green Diesel for Construction of the Diamond Green Diesel Facility in Norco, Louisiana

  12. Substitutional Boron in Nanodiamond, Bucky-Diamond, and Nanocrystalline Diamond Grain Boundaries

    SciTech Connect (OSTI)

    Barnard, Amanda S.; Sternberg, Michael G.

    2006-10-05

    Although boron has been known for many years to be a successful dopant in bulk diamond, efficient doping of nanocrystalline diamond with boron is still being developed. In general, the location, configuration, and bonding structure of boron in nanodiamond is still unknown, including the fundamental question of whether it is located within grains or grain boundaries of thin films and whether it is within the core or at the surface of nanoparticles. Presented here are density functional tight-binding simulations examining the configuration, potential energy surface, and electronic charge of substitutional boron in various types of nanocrystalline diamond. The results predict that boron is likely to be positioned at the surface of isolated particles and at the grain boundary of thin-film samples.

  13. Diamond Bar, California: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    district.12 Registered Energy Companies in Diamond Bar, California US South Coast Air Quality Management District SCAQMD References US Census Bureau Incorporated place...

  14. USES OF HYPERTHERMAL ATOMIC BEAM FOR LOW TEMPERATURE DIAMOND...

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

    quality of the film. An example is growing diamond films with large micrometer sized grains below 100 C. Reducing the growth temperature requires finding ways of selectively...

  15. Diamond Plates Create Nanostructures through Pressure, Not Chemistry

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

    Plates Create Nanostructures through Pressure, Not Chemistry - Sandia Energy Energy Search ... Diamond Plates Create Nanostructures through Pressure, Not Chemistry HomeAdvanced ...

  16. Fabrication and current optical performance of a large diamond...

    Office of Scientific and Technical Information (OSTI)

    Fabrication and current optical performance of a large diamond-machined ZnSe immersion grating Citation Details In-Document Search Title: Fabrication and current optical ...

  17. Thin Sheet of Diamond Has Worlds of Uses

    DOE R&D Accomplishments [OSTI]

    Sagoff, Jared

    2011-04-01

    A new technique from Argonne National Laboratory creates thin diamond films that are helping industry save energy and could even be used in heart and eye implants.

  18. Ultratough CVD single crystal diamond and three dimensional growth thereof

    DOE Patents [OSTI]

    Hemley, Russell J.; Mao, Ho-kwang; Yan, Chih-shiue

    2009-09-29

    The invention relates to a single-crystal diamond grown by microwave plasma chemical vapor deposition that has a toughness of at least about 30 MPa m.sup.1/2. The invention also relates to a method of producing a single-crystal diamond with a toughness of at least about 30 MPa m.sup.1/2. The invention further relates to a process for producing a single crystal CVD diamond in three dimensions on a single crystal diamond substrate.

  19. Diamond Green Diesel: Diversifying Our Transportation Fuel Supply...

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

    The Diamond Green Diesel project is a joint venture between Valero Energy Corporation and Darling International Inc. Valero Energy Corporation will direct the design, construction ...

  20. The Best of Both Worlds: Bulk Diamond Properties Realized at...

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

    a level of crystallographic and electronic ordering in purified HPHT nanodiamonds that matches fundamental properties of bulk diamond to the nanoscale while retaining its...

  1. New Superhard Form of Carbon Dents Diamond | U.S. DOE Office...

    Office of Science (SC) Website

    New Superhard Form of Carbon Dents Diamond Advanced Scientific Computing Research (ASCR) ... New Superhard Form of Carbon Dents Diamond Squeezing creates new class of material built ...

  2. Panel 2 - properties of diamond and diamond-like-carbon films

    SciTech Connect (OSTI)

    Blau, P.J.; Clausing, R.E.; Ajayi, O.O.; Liu, Y.Y.; Purohit, A.; Bartelt, P.F.; Baughman, R.H.; Bhushan, B.; Cooper, C.V.; Dugger, M.T.; Freedman, A.; Larsen-Basse, J.; McGuire, N.R.; Messier, R.F.; Noble, G.L.; Ostrowki, M.H.; Sartwell, B.D.; Wei, R.

    1993-01-01

    This panel attempted to identify and prioritize research and development needs in determining the physical, mechanical and chemical properties of diamond and diamond-like-carbon films (D/DLCF). Three specific goals were established. They were: (1) To identify problem areas which produce concern and require a better knowledge of D/DLCF properties. (2) To identify and prioritize key properties of D/DLCF to promote transportation applications. (3) To identify needs for improvement in properties-measurement methods. Each of these goals is addressed subsequently.

  3. Patterning of nanocrystalline diamond films for diamond microstructures useful in MEMS and other devices

    DOE Patents [OSTI]

    Gruen, Dieter M.; Busmann, Hans-Gerd; Meyer, Eva-Maria; Auciello, Orlando; Krauss, Alan R.; Krauss, Julie R.

    2004-11-02

    MEMS structure and a method of fabricating them from ultrananocrystalline diamond films having average grain sizes of less than about 10 nm and feature resolution of less than about one micron . The MEMS structures are made by contacting carbon dimer species with an oxide substrate forming a carbide layer on the surface onto which ultrananocrystalline diamond having average grain sizes of less than about 10 nm is deposited. Thereafter, microfabrication process are used to form a structure of predetermined shape having a feature resolution of less than about one micron.

  4. Diamond/diamond-like thin film growth in a butane plasma on unetched, unheated, N-type Si(100) substrates

    SciTech Connect (OSTI)

    Williams, E.S.; Richardson, J.S. Jr.; Anderson, D.; Starkey, K.

    1995-06-01

    Deposition of diamond/diamond-like thin films on unetched, unheated, n-type Si(100) substrates in a butane plasma is reported. An interconnection between values of index of refraction, hydrogen flow rate, butane flow rate and Rf power was determined. The H{sub 2} and C{sub 4}H{sub 10} molecules are disassociated by Rf energy to create a plasma. Carbon from the butane forms a thin diamond/diamond-like film on a suitable substrate, which in the current investigation, is n-type Si(100).

  5. Electrically conductive polycrystalline diamond and particulate metal based electrodes

    DOE Patents [OSTI]

    Swain, Greg M.; Wang, Jian

    2005-04-26

    An electrically conducting and dimensionally stable diamond (12, 14) and metal particle (13) electrode produced by electrodepositing the metal on the diamond is described. The electrode is particularly useful in harsh chemical environments and at high current densities and potentials. The electrode is particularly useful for generating hydrogen, and for reducing oxygen and oxidizing methanol in reactions which are of importance in fuel cells.

  6. Analyzing the performance of diamond-coated micro end mills.

    SciTech Connect (OSTI)

    Torres, C. D.; Heaney, P. J.; Sumant, A. V.; Hamilton, M. A.; Carpick, R. W.; Pfefferkorn, F. E.; Univ. of Wisconsin at Madison; Univ. of Pennsylvania

    2009-06-01

    A method is presented to improve the tool life and cutting performance of 300 {micro}m diameter tungsten carbide (WC) micro end mills by applying thin (<300 nm) fine-grained diamond (FGD) and nanocrystalline diamond (NCD) coatings using the hot-filament chemical vapor deposition (HF-CVD) process. The performance of the diamond-coated tools has been evaluated by comparing their performance in dry slot milling of 6061-T6 aluminum against uncoated WC micro end mills. Tool wear, coating integrity, and chip morphology were characterized using SEM and white light interferometry. The initial test results show a dramatic improvement in the tool integrity (i.e., corners not breaking off), a lower wear rate, no observable adhesion of aluminum to the diamond-coated tool, and a significant reduction in the cutting forces (>50%). Reduction of the cutting forces is attributed to the low friction and adhesion of the diamond coating. However, approximately 80% of the tools coated with the larger FGD coatings failed during testing due to delamination. Additional machining benefits were attained for the NCD films, which was obtained by using a higher nucleation density seeding process for diamond growth. This process allowed for thinner, smaller grained diamond coatings to be deposited on the micro end mills, and enabled continued operation of the tool even after the integrity of the diamond coating had been compromised. As opposed to the FGD-coated end mills, only 40% of the NCD-tools experienced delamination issues.

  7. Diamond-cBN alloy: A universal cutting material

    SciTech Connect (OSTI)

    Wang, Pei; He, Duanwei Kou, Zili; Li, Yong; Hu, Qiwei; Xu, Chao; Lei, Li; Wang, Qiming; Wang, Liping; Zhao, Yusheng; Xiong, Lun; Liu, Jing

    2015-09-07

    Diamond and cubic boron nitride (cBN) as conventional superhard materials have found widespread industrial applications, but both have inherent limitations. Diamond is not suitable for high-speed cutting of ferrous materials due to its poor chemical inertness, while cBN is only about half as hard as diamond. Because of their affinity in structural lattices and covalent bonding character, diamond and cBN could form alloys that can potentially fill the performance gap. However, the idea has never been demonstrated because samples obtained in the previous studies were too small to be tested for their practical performance. Here, we report the synthesis and characterization of transparent bulk diamond-cBN alloy compacts whose diameters (3 mm) are sufficiently large for them to be processed into cutting tools. The testing results show that the diamond-cBN alloy has superior chemical inertness over polycrystalline diamond and higher hardness than single crystal cBN. High-speed cutting tests on hardened steel and granite suggest that diamond-cBN alloy is indeed a universal cutting material.

  8. Fabrication of diamond based sensors for use in extreme environments

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

    Samudrala, Gopi K.; Moore, Samuel L.; Vohra, Yogesh K.

    2015-04-23

    Electrical and magnetic sensors can be lithographically fabricated on top of diamond substrates and encapsulated in a protective layer of chemical vapor deposited single crystalline diamond. This process when carried out on single crystal diamond anvils employed in high pressure research is termed as designer diamond anvil fabrication. These designer diamond anvils allow researchers to study electrical and magnetic properties of materials under extreme conditions without any possibility of damaging the sensing elements. We describe a novel method for the fabrication of designer diamond anvils with the use of maskless lithography and chemical vapor deposition in this paper. This methodmore » can be utilized to produce diamond based sensors which can function in extreme environments of high pressures, high and low temperatures, corrosive and high radiation conditions. Here, we demonstrate applicability of these diamonds under extreme environments by performing electrical resistance measurements during superconducting transition in rare earth doped iron-based compounds under high pressures to 12 GPa and low temperatures to 10 K.« less

  9. Fabrication of diamond based sensors for use in extreme environments

    SciTech Connect (OSTI)

    Samudrala, Gopi K.; Moore, Samuel L.; Vohra, Yogesh K.

    2015-04-23

    Electrical and magnetic sensors can be lithographically fabricated on top of diamond substrates and encapsulated in a protective layer of chemical vapor deposited single crystalline diamond. This process when carried out on single crystal diamond anvils employed in high pressure research is termed as designer diamond anvil fabrication. These designer diamond anvils allow researchers to study electrical and magnetic properties of materials under extreme conditions without any possibility of damaging the sensing elements. We describe a novel method for the fabrication of designer diamond anvils with the use of maskless lithography and chemical vapor deposition in this paper. This method can be utilized to produce diamond based sensors which can function in extreme environments of high pressures, high and low temperatures, corrosive and high radiation conditions. Here, we demonstrate applicability of these diamonds under extreme environments by performing electrical resistance measurements during superconducting transition in rare earth doped iron-based compounds under high pressures to 12 GPa and low temperatures to 10 K.

  10. NEW HIGH STRENGTH AND FASTER DRILLING TSP DIAMOND CUTTERS

    SciTech Connect (OSTI)

    Robert Radtke

    2006-01-31

    The manufacture of thermally stable diamond (TSP) cutters for drill bits used in petroleum drilling requires the brazing of two dissimilar materials--TSP diamond and tungsten carbide. The ENDURUS{trademark} thermally stable diamond cutter developed by Technology International, Inc. exhibits (1) high attachment (shear) strength, exceeding 345 MPa (50,000 psi), (2) TSP diamond impact strength increased by 36%, (3) prevents TSP fracture when drilling hard rock, and (4) maintains a sharp edge when drilling hard and abrasive rock. A novel microwave brazing (MWB) method for joining dissimilar materials has been developed. A conventional braze filler metal is combined with microwave heating which minimizes thermal residual stress between materials with dissimilar coefficients of thermal expansion. The process results in preferential heating of the lower thermal expansion diamond material, thus providing the ability to match the thermal expansion of the dissimilar material pair. Methods for brazing with both conventional and exothermic braze filler metals have been developed. Finite element modeling (FEM) assisted in the fabrication of TSP cutters controllable thermal residual stress and high shear attachment strength. Further, a unique cutter design for absorbing shock, the densification of otherwise porous TSP diamond for increased mechanical strength, and diamond ion implantation for increased diamond fracture resistance resulted in successful drill bit tests.

  11. Method and apparatus for diamond wire cutting of metal structures

    DOE Patents [OSTI]

    Parsells, Robert; Gettelfinger, Geoff; Perry, Erik; Rule, Keith

    2005-04-19

    A method and apparatus for diamond wire cutting of metal structures, such as nuclear reactor vessels, is provided. A diamond wire saw having a plurality of diamond beads with beveled or chamfered edges is provided for sawing into the walls of the metal structure. The diamond wire is guided by a plurality of support structures allowing for a multitude of different cuts. The diamond wire is cleaned and cooled by CO.sub.2 during the cutting process to prevent breakage of the wire and provide efficient cutting. Concrete can be provided within the metal structure to enhance cutting efficiency and reduce airborne contaminants. The invention can be remotely controlled to reduce exposure of workers to radioactivity and other hazards.

  12. Diamond machine tool face lapping machine

    DOE Patents [OSTI]

    Yetter, H.H.

    1985-05-06

    An apparatus for shaping, sharpening and polishing diamond-tipped single-point machine tools. The isolation of a rotating grinding wheel from its driving apparatus using an air bearing and causing the tool to be shaped, polished or sharpened to be moved across the surface of the grinding wheel so that it does not remain at one radius for more than a single rotation of the grinding wheel has been found to readily result in machine tools of a quality which can only be obtained by the most tedious and costly processing procedures, and previously unattainable by simple lapping techniques.

  13. Tensile properties of amorphous diamond films

    SciTech Connect (OSTI)

    Lavan, D.A.; Hohlfelder, R.J.; Sullivan, J.P.; Friedmann, T.A.; Mitchell, M.A.; Ashby, C.I.

    1999-12-02

    The strength and modulus of amorphous diamond, a new material for surface micromachined MEMS and sensors, was tested in uniaxial tension by pulling laterally with a flat tipped diamond in a nanoindenter. Several sample designs were attempted. Of those, only the single layer specimen with a 1 by 2 {micro}m gage cross section and a fixed end rigidly attached to the substrate was successful. Tensile load was calculated by resolving the measured lateral and normal forces into the applied tensile force and frictional losses. Displacement was corrected for machine compliance using the differential stiffness method. Post-mortem examination of the samples was performed to document the failure mode. The load-displacement data from those samples that failed in the gage section was converted to stress-strain curves using carefully measured gage cross section dimensions. Mean fracture strength was found to be 8.5 {+-} 1.4 GPa and the modulus was 831 {+-} 94 GPa. Tensile results are compared to hardness and modulus measurements made using a nanoindenter.

  14. Implantation conditions for diamond nanocrystal formation in amorphous silica

    SciTech Connect (OSTI)

    Buljan, Maja; Radovic, Iva Bogdanovic; Desnica, Uros V.; Ivanda, Mile; Jaksic, Milko; Saguy, Cecile; Kalish, Rafi; Djerdj, Igor; Tonejc, Andelka; Gamulin, Ozren

    2008-08-01

    We present a study of carbon ion implantation in amorphous silica, which, followed by annealing in a hydrogen-rich environment, leads to preferential formation of carbon nanocrystals with cubic diamond (c-diamond), face-centered cubic (n-diamond), or simple cubic (i-carbon) carbon crystal lattices. Two different annealing treatments were used: furnace annealing for 1 h and rapid thermal annealing for a brief period, which enables monitoring of early nucleation events. The influence of implanted dose and annealing type on carbon and hydrogen concentrations, clustering, and bonding were investigated. Rutherford backscattering, elastic recoil detection analysis, infrared spectroscopy, transmission electron microscopy, selected area electron diffraction, ultraviolet-visible absorption measurements, and Raman spectroscopy were used to study these carbon formations. These results, combined with the results of previous investigations on similar systems, show that preferential formation of different carbon phases (diamond, n-diamond, or i-carbon) depends on implantation energy, implantation dose, and annealing conditions. Diamond nanocrystals formed at a relatively low carbon volume density are achieved by deeper implantation and/or lower implanted dose. Higher volume densities led to n-diamond and finally to i-carbon crystal formation. This observed behavior is related to damage sites induced by implantation. The optical properties of different carbon nanocrystal phases were significantly different.

  15. Observation of diamond turned OFHC copper using Scanning Tunneling Microscopy

    SciTech Connect (OSTI)

    Grigg, D.A.; Russell, P.E.; Dow, T.A.

    1988-12-01

    Diamond turned OFHC copper samples have been observed within the past few months using the Scanning Tunneling Microscope. Initial results have shown evidence of artifacts which may be used to better understand the diamond turning process. The STM`s high resolution capability and three dimensional data representation allows observation and study of surface features unobtainable with conventional profilometry systems. Also, the STM offers a better quantitative means by which to analyze surface structures than the SEM. This paper discusses findings on several diamond turned OFHC copper samples having different cutting conditions. Each sample has been cross referenced using STM and SEM.

  16. Optical excitation of paramagnetic nitrogen in chemical vapor deposited diamond

    SciTech Connect (OSTI)

    Graeff, C.F.; Rohrer, E.; Nebel, C.E.; Stutzmann, M.; Guettler, H.; Zachai, R.

    1996-11-01

    Investigations of polycrystalline chemical vapor deposited diamond films by electron-spin-resonance (ESR), light-induced (L)ESR, and the constant photoconductivity method have identified dispersed substitutional nitrogen (P1 center) as the main paramagnetic form of N incorporated in the CVD diamond. The density of N-related paramagnetic states is strongly affected by illumination and heat treatment. It is found that the P1 center in CVD diamond gives rise to a deep donor state about 1.5 eV below the conduction band. {copyright} {ital 1996 American Institute of Physics.}

  17. Printable, flexible and stretchable diamond for thermal management

    DOE Patents [OSTI]

    Rogers, John A; Kim, Tae Ho; Choi, Won Mook; Kim, Dae Hyeong; Meitl, Matthew; Menard, Etienne; Carlisle, John

    2013-06-25

    Various heat-sinked components and methods of making heat-sinked components are disclosed where diamond in thermal contact with one or more heat-generating components are capable of dissipating heat, thereby providing thermally-regulated components. Thermally conductive diamond is provided in patterns capable of providing efficient and maximum heat transfer away from components that may be susceptible to damage by elevated temperatures. The devices and methods are used to cool flexible electronics, integrated circuits and other complex electronics that tend to generate significant heat. Also provided are methods of making printable diamond patterns that can be used in a range of devices and device components.

  18. Plasma-assisted conversion of solid hydrocarbon to diamond

    DOE Patents [OSTI]

    Valone, Steven M.; Pattillo, Stevan G.; Trkula, Mitchell; Coates, Don M.; Shah, S. Ismat

    1996-01-01

    A process of preparing diamond, e.g., diamond fiber, by subjecting a hydrocarbon material, e.g., a hydrocarbon fiber, to a plasma treatment in a gaseous feedstream for a sufficient period of time to form diamond, e.g., a diamond fiber is disclosed. The method generally further involves pretreating the hydrocarbon material prior to treatment with the plasma by heating within an oxygen-containing atmosphere at temperatures sufficient to increase crosslinking within said hydrocarbon material, but at temperatures insufficient to melt or decompose said hydrocarbon material, followed by heating at temperatures sufficient to promote outgassing of said crosslinked hydrocarbon material, but at temperatures insufficient to convert said hydrocarbon material to carbon.

  19. Slip sliding away: Graphene and diamonds prove a slippery combination...

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

    Slip sliding away: Graphene and diamonds prove a slippery combination By Jared Sagoff * May 22, 2015 Tweet EmailPrint Scientists at the U.S. Department of Energy's Argonne National...

  20. Blue Diamond, Nevada: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Blue Diamond is a census-designated place in Clark County, Nevada.1 References US...

  1. Ramp Compression of Diamond to 5 TPa: Experiments Taking Carbon...

    Office of Scientific and Technical Information (OSTI)

    Title: Ramp Compression of Diamond to 5 TPa: Experiments Taking Carbon to the Thomas-Fermi-Dirac Regime Authors: Smith, R F ; Eggert, J H ; Jeanloz, R ; Duffy, T S ; Braun, D G ; ...

  2. Engineering shallow spins in diamond with nitrogen delta-doping...

    Office of Scientific and Technical Information (OSTI)

    Title: Engineering shallow spins in diamond with nitrogen delta-doping We demonstrate nanometer-precision depth control of nitrogen-vacancy (NV) center creation near the surface of ...

  3. Substitutional Nitrogen in Nanodiamond and Bucky-Diamond Particles

    SciTech Connect (OSTI)

    Barnard, Amanda S.; Sternberg, Michael G.

    2005-09-15

    The inclusion of dopants (such as nitrogen) in diamond nanoparticles is expected to be important for use in future nanodevices, such as qubits for quantum computing. Although most commercial diamond nanoparticles contain a small fraction of nitrogen, it is still unclear whether it is located within the core or at the surface of the nanoparticle. Presented here are density functional tight binding simulations examining the configuration, potential energy surface, and electronic charge of substitutional nitrogen in nanodiamond and bucky-diamond particles. The results predict that nitrogen is likely to be positioned at the surface of both hydrogenated nanodiamond and (dehydrogenated) bucky-diamond, and that the coordination of the dopants within the particles is dependent upon the surface structure.

  4. Black Diamond, Washington: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    This article is a stub. You can help OpenEI by expanding it. Black Diamond is a city in King County, Washington. It falls under Washington's 8th congressional district.12...

  5. Diamonds are an Electronic Device’s Best Friend

    Broader source: Energy.gov [DOE]

    Researchers at Argonne National Lab recently devised a way to use diamonds to brighten the performance of electronic devices, which could put a bit more sparkle in everyone’s day.

  6. Method for the preparation of nanocrystalline diamond thin films

    DOE Patents [OSTI]

    Gruen, D.M.; Krauss, A.R.

    1998-06-30

    A method and system are disclosed for manufacturing nanocrystalline diamond film on a substrate such as field emission tips. The method involves forming a carbonaceous vapor, providing a gas stream of argon, hydrocarbon and possibly hydrogen, and combining the gas with the carbonaceous vapor, passing the combined carbonaceous vapor and gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the carbonaceous vapor and deposition of a diamond film on the field emission tip. 40 figs.

  7. Method for the preparation of nanocrystalline diamond thin films

    DOE Patents [OSTI]

    Gruen, Dieter M.; Krauss, Alan R.

    1998-01-01

    A method and system for manufacturing nanocrystalline diamond film on a substrate such as field emission tips. The method involves forming a carbonaceous vapor, providing a gas stream of argon, hydrocarbon and possibly hydrogen, and combining the gas with the carbonaceous vapor, passing the combined carbonaceous vapor and gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the carbonaceous vapor and deposition of a diamond film on the field emission tip.

  8. Analysis of the influence of tool dynamics in diamond turning

    SciTech Connect (OSTI)

    Fawcett, S.C.; Luttrell, D.E.; Keltie, R.F.

    1988-12-01

    This report describes the progress in defining the role of machine and interface dynamics on the surface finish in diamond turning. It contains a review of literature from conventional and diamond machining processes relating tool dynamics, material interactions and tool wear to surface finish. Data from experimental measurements of tool/work piece interface dynamics are presented as well as machine dynamics for the DTM at the Center.

  9. Fluorinated diamond particles bonded in a filled fluorocarbon resin matrix

    DOE Patents [OSTI]

    Taylor, Gene W.; Roybal, Herman E.

    1985-01-01

    A method of producing fluorinated diamond particles bonded in a filled fluorocarbon resin matrix. Simple hot pressing techniques permit the formation of such matrices from which diamond impregnated grinding tools and other articles of manufacture can be produced. Teflon fluorocarbon resins filled with Al.sub.2 O.sub.3 yield grinding tools with substantially improved work-to-wear ratios over grinding wheels known in the art.

  10. Fluorinated diamond particles bonded in a filled fluorocarbon resin matrix

    DOE Patents [OSTI]

    Taylor, G.W.; Roybal, H.E.

    1983-11-14

    A method of producing fluorinated diamond particles bonded in a filled fluorocarbon resin matrix. Simple hot pressing techniques permit the formation of such matrices from which diamond impregnated grinding tools and other articles of manufacture can be produced. Teflon fluorocarbon resins filled with Al/sub 2/O/sub 3/ yield grinding tools with substantially improved work-to-wear ratios over grinding wheels known in the art.

  11. BACKGROUND REVIEW OF THE BRUSH BERYLLIUM AND DIAMOND MAGNESIUM PLANTS

    Office of Legacy Management (LM)

    BACKGROUND REVIEW OF THE BRUSH BERYLLIUM AND DIAMOND MAGNESIUM PLANTS IN LUCKEY, OHIO October 27, 1989 Prepared for: U.S. Department of Energy Formerly Utilized Sites Remedial Action Program Prepared by: R.F. Weston/Office of Technical Services BACKGROUND REVIEW OF THE BRUSH BERYLLIUM AND DIAMOND MAGNESIUM PLANTS IN LUCKEY, OHIO INTRODUCTION The Department of Energy (DOE) is conducting a program to identify and examine the radiological conditions at sites used in the early years of nuclear

  12. Study of Electron Transport and Amplification in Diamond

    SciTech Connect (OSTI)

    Ben-Zvi, Ilan; Muller, Erik

    2015-01-05

    The development of the Diamond Amplified Photocathode (DAP) has produced significant results under our previous HEP funded efforts both on the fabrication of working devices and the understanding of the underlying physics governing its performance. The results presented here substantiate the use of diamond as both a secondary electron amplifier for high-brightness, high-average-current electron sources and as a photon and particle detector in harsh radiation environments. Very high average current densities (>10A/cm2) have been transported through diamond material. The transport has been measured as a function of incident photon energy and found to be in good agreement with theoretical models. Measurements of the charge transport for photon energies near the carbon K-edge (290 eV for sp3 bonded carbon) have provided insight into carrier loss due to diffusion; modeling of this aspect of charge transport is underway. The response of diamond to nanosecond x-ray pulses has been measured; in this regime the charge transport is as expected. Electron emission from hydrogenated diamond has been measured using both electron and x-ray generated carriers; a gain of 178 has been observed for electron-generated carriers. The energy spectrum of the emitted electrons has been measured, providing insight into the electron affinity and ultimately the thermal emittance. The origin of charge trapping in diamond has been investigated for both bulk and surface trapping

  13. Diagnostic of fusion neutrons on JET tokamak using diamond detector

    SciTech Connect (OSTI)

    Nemtsev, G.; Amosov, V.; Marchenko, N.; Meshchaninov, S.; Rodionov, R.; Popovichev, S.; Collaboration: JET EFDA Conbributors

    2014-08-21

    In 2011-2012, an experimental campaign with a significant yield of fusion neutrons was carried out on the JET tokamak. During this campaign the facility was equipped with two diamond detectors based on natural and artificial CVD diamond. These detectors were designed and manufactured in State Research Center of Russian Federation TRINITI. The detectors measure the flux of fast neutrons with energies above 0.2 MeV. They have been installed in the torus hall and the distance from the center of plasma was about 3 m. For some of the JET pulses in this experiment, the neutron flux density corresponded to the operational conditions in collimator channels of ITER Vertical Neutron Camera. The main objective of diamond monitors was the measurement of total fast neutron flux at the detector location and the estimation of the JET total neutron yield. The detectors operate as threshold counters. Additionally a spectrometric measurement channel has been configured that allowed us to distinguish various energy components of the neutron spectrum. In this paper we describe the neutron signal measuring and calibration procedure of the diamond detector. Fluxes of DD and DT neutrons at the detector location were measured. It is shown that the signals of total neutron yield measured by the diamond detector correlate with signals measured by the main JET neutron diagnostic based on fission chambers with high accuracy. This experiment can be considered as a successful test of diamond detectors in ITER-like conditions.

  14. Thrust faults of southern Diamond Mountains, central Nevada: Implications for hydrocarbons in Diamond Valley and at Yucca Mountain

    SciTech Connect (OSTI)

    French, D.E.

    1993-04-01

    Overmature Mississippian hydrocarbon source rocks in the southern Diamond Mountains have been interpreted to be a klippe overlying less mature source rocks and represented as an analogy to similar conditions near Yucca Mountain (Chamberlain, 1991). Geologic evidence indicates an alternative interpretation. Paleogeologic mapping indicates the presence of a thrust fault, referred to here as the Moritz Nager Thrust Fault, with Devonian rocks emplaced over Permian to Mississippian strata folded into an upright to overturned syncline, and that the overmature rocks of the Diamond Mountains are in the footwall of this thrust. The upper plate has been eroded from most of the Diamond Mountains but remnants are present at the head of Moritz Nager Canyon and at Sentinel Mountain. Devonian rocks of the upper plate comprised the earliest landslide megabreccia. Later, megabreccias of Pennsylvanian and Permian rocks of the overturned syncline of the lower plate were deposited. By this interpretation the maturity of lower-plate source rocks in the southern Diamond Mountains, which have been increased by tectonic burial, is not indicative of conditions in Diamond Valley, adjacent to the west, where upper-plate source rocks might be present in generating conditions. The interpretation that overmature source rocks of the Diamond Mountains are in a lower plate rather than in a klippe means that this area is an inappropriate model for the Eleana Range near Yucca Mountain.

  15. The 'Crazy Diamond' (and other blazars)

    SciTech Connect (OSTI)

    Vercellone, S.; Giuliani, A.

    2009-04-08

    During the first year of observations, AGILE detected several blazars at high significance: 3 C 279, 3C 454.3, PKS 1510-089, S5 0716+714, 3 C 273, MKN 421, and W Comae. We obtained long-term coverage of the Crazy Diamond 3 C 454.3, for more than 100 days at energies above 100 MeV. 3 C 273 was the first blazar detected simultaneously by the AGILE gamma-ray imaging detector and by its hard X-ray monitor. S5 0716+714, an intermediate BL Lac object, exhibited a very fast and intense gamma-ray transient event during an optical high-state phase, while MKN 421 and W Comae where detected during an AGILE target of opportunity (ToO) repointing. Thanks to the rapid dissemination of our alerts, we were able to obtain multi-wavelength ToO data from other observatories such as Spitzer, Swift, INTEGRAL, RXTE, Suzaku, MAGIC, VERITAS, as well as optical coverage by means of the WEBT Consortium and REM.

  16. Graphene diamond-like carbon films heterostructure

    SciTech Connect (OSTI)

    Zhao, Fang; Afandi, Abdulkareem; Jackman, Richard B.

    2015-03-09

    A limitation to the potential use of graphene as an electronic material is the lack of control over the 2D materials properties once it is deposited on a supporting substrate. Here, the use of Diamond-like Carbon (DLC) interlayers between the substrate and the graphene is shown to offer the prospect of overcoming this problem. The DLC films used here, more properly known as a-C:H with ?25% hydrogen content, have been terminated with N or F moieties prior to graphene deposition. It is found that nitrogen terminations lead to an optical band gap shrinkage in the DLC, whilst fluorine groups reduce the DLC's surface energy. CVD monolayer graphene subsequently transferred to DLC, N terminated DLC, and F terminated DLC has then been studied with AFM, Raman and XPS analysis, and correlated with Hall effect measurements that give an insight into the heterostructures electrical properties. The results show that different terminations strongly affect the electronic properties of the graphene heterostructures. G-F-DLC samples were p-type and displayed considerably higher mobility than the other heterostructures, whilst G-N-DLC samples supported higher carrier densities, being almost metallic in character. Since it would be possible to locally pattern the distribution of these differing surface terminations, this work offers the prospect for 2D lateral control of the electronic properties of graphene layers for device applications.

  17. Pulsed laser Raman spectroscopy in the laser-heated diamond anvil...

    Office of Scientific and Technical Information (OSTI)

    Pulsed laser Raman spectroscopy in the laser-heated diamond anvil cell Citation Details In-Document Search Title: Pulsed laser Raman spectroscopy in the laser-heated diamond anvil...

  18. Fabrication and testing of diamond-machined gratings in ZnSe...

    Office of Scientific and Technical Information (OSTI)

    Crystal samples were diamond turned on an ultra-precision lathe to identify preferred cutting directions. Using this information we diamond-flycut test gratings over a range of ...

  19. Two- and three-dimensional ultrananocrystalline diamond (UNCD) structures for a high resolution diamond-based MEMS technology.

    SciTech Connect (OSTI)

    Auciello, O.; Krauss, A. R.; Gruen, D. M.; Busmann, H. G.; Meyer, E. M.; Tucek, J.; Sumant, A.; Jayatissa, A.; Moldovan, N.; Mancini, D. C.; Gardos, M. N.

    2000-01-17

    Silicon is currently the most commonly used material for the fabrication of microelectromechanical systems (MEMS). However, silicon-based MEMS will not be suitable for long-endurance devices involving components rotating at high speed, where friction and wear need to be minimized, components such as 2-D cantilevers that may be subjected to very large flexural displacements, where stiction is a problem, or components that will be exposed to corrosive environments. The mechanical, thermal, chemical, and tribological properties of diamond make it an ideal material for the fabrication of long-endurance MEMS components. Cost-effective fabrication of these components could in principle be achieved by coating Si with diamond films and using conventional lithographic patterning methods in conjunction with e. g. sacrificial Ti or SiO{sub 2} layers. However, diamond coatings grown by conventional chemical vapor deposition (CVD) methods exhibit a coarse-grained structure that prevents high-resolution patterning, or a fine-grained microstructure with a significant amount of intergranular non-diamond carbon. The authors demonstrate here the fabrication of 2-D and 3-D phase-pure ultrananocrystalline diamond (UNCD) MEMS components by coating Si with UNCD films, coupled with lithographic patterning methods involving sacrificial release layers. UNCD films are grown by microwave plasma CVD using C{sub 60}-Ar or CH{sub 4}-Ar gas mixtures, which result in films that have 3--5 nm grain size, are 10--20 times smoother than conventionally grown diamond films, are extremely resistant to corrosive environments, and are predicted to have a brittle fracture strength similar to that of single crystal diamond.

  20. Effects of hydrogen atoms on surface conductivity of diamond film

    SciTech Connect (OSTI)

    Liu, Fengbin Cui, Yan; Qu, Min; Di, Jiejian

    2015-04-15

    To investigate the effects of surface chemisorbed hydrogen atoms and hydrogen atoms in the subsurface region of diamond on surface conductivity, models of hydrogen atoms chemisorbed on diamond with (100) orientation and various concentrations of hydrogen atoms in the subsurface layer of the diamond were built. By using the first-principles method based on density functional theory, the equilibrium geometries and densities of states of the models were studied. The results showed that the surface chemisorbed hydrogen alone could not induce high surface conductivity. In addition, isolated hydrogen atoms in the subsurface layer of the diamond prefer to exist at the bond centre site of the C-C bond. However, such a structure would induce deep localized states, which could not improve the surface conductivity. When the hydrogen concentration increases, the C-H-C-H structure and C-3H{sub bc}-C structure in the subsurface region are more stable than other configurations. The former is not beneficial to the increase of the surface conductivity. However, the latter would induce strong surface states near the Fermi level, which would give rise to high surface conductivity. Thus, a high concentration of subsurface hydrogen atoms in diamond would make significant contributions to surface conductivity.

  1. Heavy-ion irradiation induced diamond formation in carbonaceous materials.

    SciTech Connect (OSTI)

    Daulton, T. L.

    1999-01-08

    The basic mechanisms of metastable phase formation produced under highly non-equilibrium thermodynamic conditions within high-energy particle tracks are investigated. In particular, the possible formation of diamond by heavy-ion irradiation of graphite at ambient temperature is examined. This work was motivated, in part, by earlier studies which discovered nanometer-grain polycrystalline diamond aggregates of submicron-size in uranium-rich carbonaceous mineral assemblages of Precambrian age. It was proposed that the radioactive decay of uranium formed diamond in the fission particle tracks produced in the carbonaceous minerals. To test the hypothesis that nanodiamonds can form by ion irradiation, fine-grain polycrystalline graphite sheets were irradiated with 400 MeV Kr ions. The ion irradiated graphite (and unirradiated graphite control) were then subjected to acid dissolution treatments to remove the graphite and isolate any diamonds that were produced. The acid residues were then characterized by analytical and high-resolution transmission electron microscopy. The acid residues of the ion-irradiated graphite were found to contain ppm concentrations of nanodiamonds, suggesting that ion irradiation of bulk graphite at ambient temperature can produce diamond.

  2. Dynamic compression of synthetic diamond windows (final report for LDRD project 93531).

    SciTech Connect (OSTI)

    Dolan, Daniel H.,

    2008-09-01

    Diamond is an attractive dynamic compression window for many reasons: high elastic limit,large mechanical impedance, and broad transparency range. Natural diamonds, however, aretoo expensive to be used in destructive experiments. Chemical vapor deposition techniquesare now able to produce large single-crystal windows, opening up many potential dynamiccompression applications. This project studied the behavior of synthetic diamond undershock wave compression. The results suggest that synthetic diamond could be a usefulwindow in this field, though complete characterization proved elusive.3

  3. Hydrogen Storage in Nano-Phase Diamond at High Temperature and Its Release

    SciTech Connect (OSTI)

    Tushar K Ghosh

    2008-10-13

    The objectives of this proposed research were: 91) Separation and storage of hydrogen on nanophase diamonds. It is expected that the produced hydrogen, which will be in a mixture, can be directed to a nanophase diamond system directly, which will not only store the hydrogen, but also separate it from the gas mixture, and (2) release of the stored hydrogen from the nanophase diamond.

  4. Capacitively coupled RF diamond-like-carbon reactor

    DOE Patents [OSTI]

    Devlin, David James; Coates, Don Mayo; Archuleta, Thomas Arthur; Barbero, Robert Steven

    2000-01-01

    A process of coating a non-conductive fiber with diamond-like carbon, including passing a non-conductive fiber between a pair of parallel metal grids within a reaction chamber, introducing a hydrocarbon gas into the reaction chamber, forming a plasma within the reaction chamber for a sufficient period of time whereby diamond-like carbon is formed upon the non-conductive fiber, is provided together with a reactor chamber for deposition of diamond-like carbon upon a non-conductive fiber, including a vacuum chamber, a cathode assembly including a pair of electrically isolated opposingly parallel metal grids spaced apart at a distance of less than about 1 centimeter, an anode, a means of introducing a hydrocarbon gas into said vacuum chamber, and a means of generating a plasma within said vacuum chamber.

  5. Diamond-Silicon Carbide Composite And Method For Preparation Thereof

    DOE Patents [OSTI]

    Qian, Jiang; Zhao, Yusheng

    2005-09-06

    Fully dense, diamond-silicon carbide composites are prepared from ball-milled microcrystalline diamond/amorphous silicon powder mixture. The ball-milled powder is sintered (P=5-8 GPa, T=1400K-2300K) to form composites having high fracture toughness. A composite made at 5 GPa/1673K had a measured fracture toughness of 12 MPa.multidot.m.sup.1/2. By contrast, liquid infiltration of silicon into diamond powder at 5 GPa/1673K produces a composite with higher hardness but lower fracture toughness. X-ray diffraction patterns and Raman spectra indicate that amorphous silicon is partially transformed into nanocrystalline silicon at 5 GPa/873K, and nanocrystalline silicon carbide forms at higher temperatures.

  6. Plasma deposited diamond-like carbon films for large neutralarrays

    SciTech Connect (OSTI)

    Brown, I.G.; Blakely, E.A.; Bjornstad, K.A.; Galvin, J.E.; Monteiro, O.R.; Sangyuenyongpipat, S.

    2004-07-15

    To understand how large systems of neurons communicate, we need to develop methods for growing patterned networks of large numbers of neurons. We have found that diamond-like carbon thin films formed by energetic deposition from a filtered vacuum arc carbon plasma can serve as ''neuron friendly'' substrates for the growth of large neural arrays. Lithographic masks can be used to form patterns of diamond-like carbon, and regions of selective neuronal attachment can form patterned neural arrays. In the work described here, we used glass microscope slides as substrates on which diamond-like carbon was deposited. PC-12 rat neurons were then cultured on the treated substrates and cell growth monitored. Neuron growth showed excellent contrast, with prolific growth on the treated surfaces and very low growth on the untreated surfaces. Here we describe the vacuum arc plasma deposition technique employed, and summarize results demonstrating that the approach can be used to form large patterns of neurons.

  7. Synthesis and characterization of a nanocrystalline diamond aerogel

    SciTech Connect (OSTI)

    Pauzauskie, Peter J.; Crowhurst, Jonathan C.; Worsley, Marcus A.; Laurence, Ted A.; Kilcoyne, A. L. David; Wang, Yinmin; Willey, Trevor M.; Visbeck, Kenneth S.; Fakra, Sirine C.; Evans, William J.; Zaug, Joseph M.; Satcher, Jr., Joe H.

    2011-07-06

    Aerogel materials have myriad scientific and technological applications due to their large intrinsic surface areas and ultralow densities. However, creating a nanodiamond aerogel matrix has remained an outstanding and intriguing challenge. Here we report the high-pressure, high-temperature synthesis of a diamond aerogel from an amorphous carbon aerogel precursor using a laser-heated diamond anvil cell. Neon is used as a chemically inert, near-hydrostatic pressure medium that prevents collapse of the aerogel under pressure by conformally filling the aerogel's void volume. Electron and X-ray spectromicroscopy confirm the aerogel morphology and composition of the nanodiamond matrix. Time-resolved photoluminescence measurements of recovered material reveal the formation of both nitrogen- and silicon- vacancy point-defects, suggesting a broad range of applications for this nanocrystalline diamond aerogel.

  8. Smooth diamond films as low friction, long wear surfaces

    DOE Patents [OSTI]

    Gruen, Dieter M.; Krauss, Alan R.; Erdemir, Ali; Bindal, Cuma; Zuiker, Christopher D.

    1999-01-01

    An article and method of manufacture of a nanocrystalline diamond film. The nanocrystalline film is prepared by forming a carbonaceous vapor, providing an inert gas containing gas stream and combining the gas stream with the carbonaceous containing vapor. A plasma of the combined vapor and gas stream is formed in a chamber and fragmented carbon species are deposited onto a substrate to form the nanocrystalline diamond film having a root mean square flatness of about 50 nm deviation from flatness in the as deposited state.

  9. Diamond turning of Si and Ge single crystals

    SciTech Connect (OSTI)

    Blake, P.; Scattergood, R.O.

    1988-12-01

    Single-point diamond turning studies have been completed on Si and Ge crystals. A new process model was developed for diamond turning which is based on a critical depth of cut for plastic flow-to-brittle fracture transitions. This concept, when combined with the actual machining geometry for single-point turning, predicts that {open_quotes}ductile{close_quotes} machining is a combined action of plasticity and fracture. Interrupted cutting experiments also provide a meant to directly measure the critical depth parameter for given machining conditions.

  10. Simplified models of growth, defect formation, and thermal conductivity in diamond chemical vapor deposition

    SciTech Connect (OSTI)

    Coltrin, M.E.; Dandy, D.S.

    1996-04-01

    A simplified surface reaction mechanism is presented for the CVD of diamond thin films. The mechanism also accounts for formation of point defects in the diamond lattice, an alternate, undesirable reaction pathway. Both methyl radicals and atomic C are considered as growth precursors. While not rigorous in all details, the mechanism is useful in describing the CVD diamond process over a wide range of reaction conditions. It should find utility in reactor modeling studies, for example in optimizing diamond growth rate while minimizing defect formation. This report also presents a simple model relating the diamond point-defect density to the thermal conductivity of the material.

  11. Large piezoresistive effect in surface conductive nanocrystalline diamond

    SciTech Connect (OSTI)

    Janssens, S. D. Haenen, K.; Drijkoningen, S.

    2014-09-08

    Surface conductivity in hydrogen-terminated single crystal diamond is an intriguing phenomenon for fundamental reasons as well as for application driven research. Surface conductivity is also observed in hydrogen-terminated nanocrystalline diamond although the electronic transport mechanisms remain unclear. In this work, the piezoresistive properties of intrinsic surface conductive nanocrystalline diamond are investigated. A gauge factor of 35 is calculated from bulging a diamond membrane of 350 nm thick, with a diameter of 656 μm and a sheet resistance of 1.45 MΩ/sq. The large piezoresistive effect is reasoned to originate directly from strain-induced changes in the resistivity of the grain boundaries. Additionally, we ascribe a small time-dependent fraction of the piezoresistive effect to charge trapping of charge carriers at grain boundaries. In conclusion, time-dependent piezoresistive effect measurements act as a tool for deeper understanding the complex electronic transport mechanisms induced by grain boundaries in a polycrystalline material or nanocomposite.

  12. 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.

  13. Diamond Wire Saw for Precision Machining of Laser Target Components

    SciTech Connect (OSTI)

    Bono, M J; Bennett, D W

    2005-08-08

    The fabrication of precision laser targets requires a wide variety of specialized mesoscale manufacturing techniques. The diamond wire saw developed in this study provides the capability to precisely section meso-scale workpieces mounted on the assembly stations used by the Target Fabrication Group. This new capability greatly simplifies the fabrication of many types of targets and reduces the time and cost required to build the targets. A variety of materials are used to fabricate targets, including metals, plastics with custom designed chemical formulas, and aerogels of various densities. The materials are usually provided in the form of small pieces or cast rods that must be machined to the required shape. Many of these materials, such as metals and some plastics, can be trimmed using a parting tool on a diamond turning machine. However, other materials, such as aerogels and brittle materials, cannot be adequately cut with a parting tool. In addition, the geometry of the parts often requires that the workpieces be held in a special assembly station, which excludes the use of a parting tool. In the past, these materials were sectioned using a small, handheld coping saw that used a diamond-impregnated wire as a blade. This miniature coping saw was effective, but it required several hours to cut through certain materials. Furthermore, the saw was guided by hand and often caused significant damage to fragile aerogels. To solve these problems, the diamond wire saw shown in Figure 1 was developed. The diamond wire saw is designed to machine through materials that are mounted in the Target Fabrication Group's benchtop assembly stations. These assembly stations are the primary means of aligning and assembling target components, and there is often a need to machine materials while they are mounted in the assembly stations. Unfortunately, commercially available saws are designed for very different applications and are far too large to be used with the assembly stations

  14. Process for making a cesiated diamond film field emitter and field emitter formed therefrom

    DOE Patents [OSTI]

    Anderson, David F.; Kwan, Simon W.

    1999-01-01

    A process for making a cesiated diamond film comprises (a) depositing a quantity of cesium iodide on the diamond film in a vacuum of between about 10.sup.-4 Torr and about 10.sup.-7 Torr, (b) increasing the vacuum to at least about 10.sup.-8 Torr, and (c) imposing an electron beam upon the diamond film, said electron beam having an energy sufficient to dissociate said cesium iodide and to incorporate cesium into interstices of the diamond film. The cesiated diamond film prepared according to the process has an operating voltage that is reduced by a factor of at least approximately 2.5 relative to conventional, non-cesiated diamond film field emitters.

  15. Process for making a cesiated diamond film field emitter and field emitter formed therefrom

    DOE Patents [OSTI]

    Anderson, D.F.; Kwan, S.W.

    1999-03-30

    A process for making a cesiated diamond film comprises (a) depositing a quantity of cesium iodide on the diamond film in a vacuum of between about 10{sup {minus}4} Torr and about 10{sup {minus}7} Torr, (b) increasing the vacuum to at least about 10{sup {minus}8} Torr, and (c) imposing an electron beam upon the diamond film, said electron beam having an energy sufficient to dissociate said cesium iodide and to incorporate cesium into interstices of the diamond film. The cesiated diamond film prepared according to the process has an operating voltage that is reduced by a factor of at least approximately 2.5 relative to conventional, non-cesiated diamond film field emitters. 2 figs.

  16. Low substrate temperature deposition of diamond coatings derived from glassy carbon

    DOE Patents [OSTI]

    Holcombe, Jr., Cressie E.; Seals, Roland D.

    1995-01-01

    A process for depositing a diamond coating on a substrate at temperatures less than about 550.degree. C. A powder mixture of glassy carbon and diamond particles is passed through a high velocity oxy-flame apparatus whereupon the powders are heated prior to impingement at high velocity against the substrate. The powder mixture contains between 5 and 50 powder volume percent of the diamond particles, and preferably between 5 and 15 powder volume percent. The particles have a size from about 5 to about 100 micrometers, with the diamond particles being about 5 to about 30 micrometers. The flame of the apparatus provides a velocity of about 350 to about 1000 meters per second, with the result that upon impingement upon the substrate, the glassy carbon is phase transformed to diamond as coaxed by the diamond content of the powder mixture.

  17. Low substrate temperature deposition of diamond coatings derived from glassy carbon

    DOE Patents [OSTI]

    Holcombe, C.E. Jr.; Seals, R.D.

    1995-09-26

    A process is disclosed for depositing a diamond coating on a substrate at temperatures less than about 550 C. A powder mixture of glassy carbon and diamond particles is passed through a high velocity oxy-flame apparatus whereupon the powders are heated prior to impingement at high velocity against the substrate. The powder mixture contains between 5 and 50 powder volume percent of the diamond particles, and preferably between 5 and 15 powder volume percent. The particles have a size from about 5 to about 100 micrometers, with the diamond particles being about 5 to about 30 micrometers. The flame of the apparatus provides a velocity of about 350 to about 1000 meters per second, with the result that upon impingement upon the substrate, the glassy carbon is phase transformed to diamond as coaxed by the diamond content of the powder mixture. 2 figs.

  18. Method for producing fluorinated diamond-like carbon films

    DOE Patents [OSTI]

    Hakovirta, Marko J.; Nastasi, Michael A.; Lee, Deok-Hyung; He, Xiao-Ming

    2003-06-03

    Fluorinated, diamond-like carbon (F-DLC) films are produced by a pulsed, glow-discharge plasma immersion ion processing procedure. The pulsed, glow-discharge plasma was generated at a pressure of 1 Pa from an acetylene (C.sub.2 H.sub.2) and hexafluoroethane (C.sub.2 F.sub.6) gas mixture, and the fluorinated, diamond-like carbon films were deposited on silicon <100>substrates. The film hardness and wear resistance were found to be strongly dependent on the fluorine content incorporated into the coatings. The hardness of the F-DLC films was found to decrease considerably when the fluorine content in the coatings reached about 20%. The contact angle of water on the F-DLC coatings was found to increase with increasing film fluorine content and to saturate at a level characteristic of polytetrafluoroethylene.

  19. Adhesion at WC/diamond interfaces - A theoretical study

    SciTech Connect (OSTI)

    Padmanabhan, Haricharan; Rao, M. S. Ramachandra; Nanda, B. R. K.

    2015-06-24

    We investigate the adhesion at the interface of face-centered tungsten-carbide (001) and diamond (001) from density-functional calculations. Four high-symmetry model interfaces, representing different lattice orientations for either side of the interface, are constructed to incorporate different degrees of strain arising due to lattice mismatch. The adhesion, estimated from the ideal work of separation, is found to be in the range of 4 - 7 J m{sup −2} and is comparable to that of metal-carbide interfaces. Maximum adhesion occurs when WC and diamond slabs have the same orientation, even though such a growth induces large epitaxial strain at the interface. From electronic structure calculations, we attribute the adhesion to covalent interaction between carbon p-orbitals as well as partial ionic interaction between the tungsten d- and carbon p-orbitals across the interface.

  20. Diamond neutral particle spectrometer for fusion reactor ITER

    SciTech Connect (OSTI)

    Krasilnikov, V.; Amosov, V.; Kaschuck, Yu.; Skopintsev, D.

    2014-08-21

    A compact diamond neutral particle spectrometer with digital signal processing has been developed for fast charge-exchange atoms and neutrons measurements at ITER fusion reactor conditions. This spectrometer will play supplementary role for Neutral Particle Analyzer providing 10 ms time and 30 keV energy resolutions for fast particle spectra in non-tritium ITER phase. These data will also be implemented for independent studies of fast ions distribution function evolution in various plasma scenarios with the formation of a single fraction of high-energy ions. In tritium ITER phase the DNPS will measure 14 MeV neutrons spectra. The spectrometer with digital signal processing can operate at peak counting rates reaching a value of 10{sup 6} cps. Diamond neutral particle spectrometer is applicable to future fusion reactors due to its high radiation hardness, fast response and high energy resolution.

  1. Characterization of textured polycrystalline diamond by electron spin resonance spectroscopy

    SciTech Connect (OSTI)

    Graeff, C.F.; Nebel, C.E.; Stutzmann, M.; Floeter, A.; Zachai, R.

    1997-01-01

    Electron spin resonance (ESR) is shown to be a useful and versatile technique for the detection and characterization of preferred orientation effects in polycrystalline diamond films. A nitrogen related center known as P1 is used for this purpose. The ESR signal coming from this center is composed of a central line and hyperfine satellite lines. It is found that crystallite disorientation causes a linewidth broadening of the satellite lines, which can thus be used to quantitatively characterize the diamond film texture. It is shown that the method is able to separate contributions of disorder induced by rotations of the crystallites around the growth direction from other contributions. The general conditions in which the method can be applied, and its applicability to other materials, are discussed. {copyright} {ital 1997 American Institute of Physics.}

  2. Radiation hardness of three-dimensional polycrystalline diamond detectors

    SciTech Connect (OSTI)

    Lagomarsino, Stefano Sciortino, Silvio; Bellini, Marco; Corsi, Chiara; Cindro, Vladimir; Kanxheri, Keida; Servoli, Leonello; Morozzi, Arianna; Passeri, Daniele; Schmidt, Christian J.

    2015-05-11

    The three-dimensional concept in particle detection is based on the fabrication of columnar electrodes perpendicular to the surface of a solid state radiation sensor. It permits to improve the radiation resistance characteristics of a material by lowering the necessary bias voltage and shortening the charge carrier path inside the material. If applied to a long-recognized exceptionally radiation-hard material like diamond, this concept promises to pave the way to the realization of detectors of unprecedented performances. We fabricated conventional and three-dimensional polycrystalline diamond detectors, and tested them before and after neutron damage up to 1.2 ×10{sup 16 }cm{sup −2}, 1 MeV-equivalent neutron fluence. We found that the signal collected by the three-dimensional detectors is up to three times higher than that of the conventional planar ones, at the highest neutron damage ever experimented.

  3. Molecular dynamics simulation of radiation damage cascades in diamond

    SciTech Connect (OSTI)

    Buchan, J. T.; Robinson, M.; Christie, H. J.; Roach, D. L.; Ross, D. K.; Marks, N. A.

    2015-06-28

    Radiation damage cascades in diamond are studied by molecular dynamics simulations employing the Environment Dependent Interaction Potential for carbon. Primary knock-on atom (PKA) energies up to 2.5 keV are considered and a uniformly distributed set of 25 initial PKA directions provide robust statistics. The simulations reveal the atomistic origins of radiation-resistance in diamond and provide a comprehensive computational analysis of cascade evolution and dynamics. As for the case of graphite, the atomic trajectories are found to have a fractal-like character, thermal spikes are absent and only isolated point defects are generated. Quantitative analysis shows that the instantaneous maximum kinetic energy decays exponentially with time, and that the timescale of the ballistic phase has a power-law dependence on PKA energy. Defect recombination is efficient and independent of PKA energy, with only 50% of displacements resulting in defects, superior to graphite where the same quantity is nearly 75%.

  4. High-Current Cold Cathode Employing Diamond and Related Materials

    SciTech Connect (OSTI)

    Hirshfield, Jay L.

    2014-10-22

    The essence of this project was for diamond films to be deposited on cold cathodes to improve their emission properties. Films with varying morphology, composition, and size of the crystals were deposited and the emission properties of the cathodes that utilize such films were studied. The prototype cathodes fabricated by the methods developed during Phase I were tested and evaluated in an actual high-power RF device during Phase II. These high-power tests used the novel active RF pulse compression system and the X-band magnicon test facility at US Naval Research Laboratory. In earlier tests, plasma switches were employed, while tests under this project utilized electron-beam switching. The intense electron beams required in the switches were supplied from cold cathodes embodying diamond films with varying morphology, including uncoated molybdenum cathodes in the preliminary tests. Tests with uncoated molybdenum cathodes produced compressed X-band RF pulses with a peak power of 91 MW, and a maximum power gain of 16.5:1. Tests were also carried out with switches employing diamond coated cathodes. The pulse compressor was based on use of switches employing electron beam triggering to effect mode conversion. In experimental tests, the compressor produced 165 MW in a ~ 20 ns pulse at ~18× power gain and ~ 140 MW at ~ 16× power gain in a 16 ns pulse with a ~ 7 ns flat-top. In these tests, molybdenum blade cathodes with thin diamond coatings demonstrated good reproducible emission uniformity with a 100 kV, 100 ns high voltage pulse. The new compressor does not have the limitations of earlier types of active pulse compressors and can operate at significantly higher electric fields without breakdown.

  5. Method of forming fluorine-bearing diamond layer on substrates, including tool substrates

    DOE Patents [OSTI]

    Chang, R. P. H.; Grannen, Kevin J.

    2002-01-01

    A method of forming a fluorine-bearing diamond layer on non-diamond substrates, especially on tool substrates comprising a metal matrix and hard particles, such as tungsten carbide particles, in the metal matrix. The substrate and a fluorine-bearing plasma or other gas are then contacted under temperature and pressure conditions effective to nucleate fluorine-bearing diamond on the substrate. A tool insert substrate is treated prior to the diamond nucleation and growth operation by etching both the metal matrix and the hard particles using suitable etchants.

  6. Diamond Amplified Photocathode at BNL | U.S. DOE Office of Science...

    Office of Science (SC) Website

    Diamond Amplified Photocathode at BNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Applications of Nuclear Science Applications of ...

  7. Corrosive Resistant Diamond Coatings for the Acid Based Thermo-Chemical Hydrogen Cycles

    SciTech Connect (OSTI)

    Mark A. Prelas

    2009-06-25

    This project was designed to test diamond, diamond-like and related materials in environments that are expected in thermochemical cycles. Our goals were to build a High Temperature Corrosion Resistance (HTCR) test stand and begin testing the corrosive properties of barious materials in a high temperature acidic environment in the first year. Overall, we planned to test 54 samples each of diamond and diamond-like films (of 1 cm x 1 cm area). In addition we use a corrosion acceleration method by treating the samples at a temperature much larger than the expected operating temperature. Half of the samples will be treated with boron using the FEDOA process.

  8. Amorphous Diamond Flat Panel Displays - Final Report of ER-LTR CRADA project with SI Diamond Technology

    SciTech Connect (OSTI)

    Ager III, Joel W.

    1998-05-08

    The objective of this project was to determine why diamond-based films are unusually efficient electron emitters (field emission cathodes) at room temperature. Efficient cathodes based on diamond are being developed by SI Diamond Technology (SIDT) as components for bright, sunlight-readable, flat panel displays. When the project started, it was known that only a small fraction (<1%) of the cathode area is active in electron emission and that the emission sites themselves are sub-micron in size. The critical challenge of this project was to develop new microcharacterization methods capable of examining known emission sites. The research team used a combination of cathode emission imaging (developed at SIDT), micro-Raman spectroscopy (LBNL), and electron microscopy and spectroscopy (National Center for Electron Microscopy, LBNL) to examine the properties of known emission sites. The most significant accomplishment of the project was the development at LBNL of a very high resolution scanning probe that, for the first time, measured simultaneously the topography and electrical characteristics of single emission sites. The increased understanding of the emission mechanism helped SIDT to develop a new cathode material,''nano-diamond,'' which they have incorporated into their Field Emission Picture Element (FEPix) product. SIDT is developing large-format flat panel displays based on these picture elements that will be brighter and more efficient than existing outdoor displays such as Jumbotrons. The energy saving that will be realized if field emission displays are introduced commercially is in line with the energy conservation mission of DOE. The unique characterization tools developed in this project (particularly the new scanning microscopy method) are being used in ongoing BES-funded basic research.

  9. Annealing dependence of diamond-metal Schottky barrier heights probed by hard x-ray photoelectron spectroscopy

    SciTech Connect (OSTI)

    Gaowei, M.; Muller, E. M.; Rumaiz, A. K.; Weiland, C.; Cockayne, E.; Woicik, J. C.; Jordan-Sweet, J.; Smedley, J.

    2012-05-14

    Hard x-ray photoelectron spectroscopy was applied to investigate the diamond-metal Schottky barrier heights for several metals and diamond surface terminations. The position of the diamond valence-band maximum was determined by theoretically calculating the diamond density of states and applying cross section corrections. The diamond-platinum Schottky barrier height was lowered by 0.2 eV after thermal annealing, indicating annealing may increase carrier injection in diamond devices leading to photoconductive gain. The platinum contacts on oxygen-terminated diamond was found to provide a higher Schottky barrier and therefore a better blocking contact than that of the silver contact in diamond-based electronic devices.

  10. High pressure studies using two-stage diamond micro-anvils grown by chemical vapor deposition

    SciTech Connect (OSTI)

    Vohra, Yogesh K.; Samudrala, Gopi K.; Moore, Samuel L.; Montgomery, Jeffrey M.; Tsoi, Georgiy M.; Velisavljevic, Nenad

    2015-06-10

    Ultra-high static pressures have been achieved in the laboratory using a two-stage micro-ball nanodiamond anvils as well as a two-stage micro-paired diamond anvils machined using a focused ion-beam system. The two-stage diamond anvils’ designs implemented thus far suffer from a limitation of one diamond anvil sliding past another anvil at extreme conditions. We describe a new method of fabricating two-stage diamond micro-anvils using a tungsten mask on a standard diamond anvil followed by microwave plasma chemical vapor deposition (CVD) homoepitaxial diamond growth. A prototype two stage diamond anvil with 300 μm culet and with a CVD diamond second stage of 50 μm in diameter was fabricated. We have carried out preliminary high pressure X-ray diffraction studies on a sample of rare-earth metal lutetium sample with a copper pressure standard to 86 GPa. Furthermore, the micro-anvil grown by CVD remained intact during indentation of gasket as well as on decompression from the highest pressure of 86 GPa.

  11. High pressure studies using two-stage diamond micro-anvils grown by chemical vapor deposition

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

    Vohra, Yogesh K.; Samudrala, Gopi K.; Moore, Samuel L.; Montgomery, Jeffrey M.; Tsoi, Georgiy M.; Velisavljevic, Nenad

    2015-06-10

    Ultra-high static pressures have been achieved in the laboratory using a two-stage micro-ball nanodiamond anvils as well as a two-stage micro-paired diamond anvils machined using a focused ion-beam system. The two-stage diamond anvils’ designs implemented thus far suffer from a limitation of one diamond anvil sliding past another anvil at extreme conditions. We describe a new method of fabricating two-stage diamond micro-anvils using a tungsten mask on a standard diamond anvil followed by microwave plasma chemical vapor deposition (CVD) homoepitaxial diamond growth. A prototype two stage diamond anvil with 300 μm culet and with a CVD diamond second stage ofmore » 50 μm in diameter was fabricated. We have carried out preliminary high pressure X-ray diffraction studies on a sample of rare-earth metal lutetium sample with a copper pressure standard to 86 GPa. Furthermore, the micro-anvil grown by CVD remained intact during indentation of gasket as well as on decompression from the highest pressure of 86 GPa.« less

  12. Effects of disorder state and interfacial layer on thermal transport in copper/diamond system

    SciTech Connect (OSTI)

    Sinha, V.; Gengler, J. J.; Muratore, C.; Spowart, J. E.

    2015-02-21

    The characterization of Cu/diamond interface thermal conductance (h{sub c}) along with an improved understanding of factors affecting it are becoming increasingly important, as Cu-diamond composites are being considered for electronic packaging applications. In this study, ∼90 nm thick Cu layers were deposited on synthetic and natural single crystal diamond substrates. In several specimens, a Ti-interface layer of thickness ≤3.5 nm was sputtered between the diamond substrate and the Cu top layer. The h{sub c} across Cu/diamond interfaces for specimens with and without a Ti-interface layer was determined using time-domain thermoreflectance. The h{sub c} is ∼2× higher for similar interfacial layers on synthetic versus natural diamond substrate. The nitrogen concentration of synthetic diamond substrate is four orders of magnitude lower than natural diamond. The difference in nitrogen concentration can lead to variations in disorder state, with a higher nitrogen content resulting in a higher level of disorder. This difference in disorder state potentially can explain the variations in h{sub c}. Furthermore, h{sub c} was observed to increase with an increase of Ti-interface layer thickness. This was attributed to an increased adhesion of Cu top layer with increasing Ti-interface layer thickness, as observed qualitatively in the current study.

  13. Method of bonding diamonds in a matrix and articles thus produced

    DOE Patents [OSTI]

    Taylor, G.W.

    1981-01-27

    By fluorinating diamond grit, the grit may be readily bonded into a fluorocarbon resin matrix. The matrix is formed by simple hot pressing techniques. Diamond grinding wheels may advantageously be manufactured using such a matrix. Teflon fluorocarbon resins are particularly well suited for using in forming the matrix.

  14. Thermal conductivity changes upon neutron transmutation of {sup 10}B doped diamond

    SciTech Connect (OSTI)

    Jagannadham, K., E-mail: jag-kasichainula@ncsu.edu [Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Verghese, K. [Nuclear Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Butler, J. E. [Code 6174, Naval research Laboratory, Washington, District of Columbia 20375 (United States)

    2014-08-28

    {sup 10}B doped p-type diamond samples were subjected to neutron transmutation reaction using thermal neutron flux of 0.9 × 10{sup 13} cm{sup ?2} s{sup ?1} and fast neutron flux of 0.09 × 10{sup 13} cm{sup ?2} s{sup ?1}. Another sample of epilayer grown on type IIa (110) single crystal diamond substrate was subjected to equal thermal and fast neutron flux of 10{sup 14}?cm{sup ?2} s{sup ?1}. The defects in the diamond samples were previously characterized by different methods. In the present work, thermal conductivity of these diamond samples was determined at room temperature by transient thermoreflectance method. The thermal conductivity change in the samples as a function of neutron fluence is explained by the phonon scattering from the point defects and disordered regions. The thermal conductivity of the diamond samples decreased more rapidly initially and less rapidly for larger neutron fluence. In addition, the thermal conductivity in type IIb diamond decreased less rapidly with thermal neutron fluence compared to the decrease in type IIa diamond subjected to fast neutron fluence. It is concluded that the rate of production of defects during transmutation reaction is slower when thermal neutrons are used. The thermal conductivity of epilayer of diamond subjected to high thermal and fast neutron fluence is associated with the covalent carbon network in the composite structure consisting of disordered carbon and sp{sup 2} bonded nanocrystalline regions.

  15. Vacuum encapsulated, high temperature diamond amplified cathode capsule and method for making same

    DOE Patents [OSTI]

    Rao, Triveni; Walsh, Josh; Gangone, Elizabeth

    2015-12-29

    A vacuum encapsulated, hermetically sealed cathode capsule for generating an electron beam of secondary electrons, which generally includes a cathode element having a primary emission surface adapted to emit primary electrons, an annular insulating spacer, a diamond window element comprising a diamond material and having a secondary emission surface adapted to emit secondary electrons in response to primary electrons impinging on the diamond window element, a first high-temperature solder weld disposed between the diamond window element and the annular insulating spacer and a second high-temperature solder weld disposed between the annular insulating spacer and the cathode element. The cathode capsule is formed by a high temperature weld process under vacuum such that the first solder weld forms a hermetical seal between the diamond window element and the annular insulating spacer and the second solder weld forms a hermetical seal between the annular spacer and the cathode element whereby a vacuum encapsulated chamber is formed within the capsule.

  16. Vacuum encapsulated hermetically sealed diamond amplified cathode capsule and method for making same

    DOE Patents [OSTI]

    Rao, Triveni; Walsh, John; Gangone, Elizabeth

    2014-12-30

    A vacuum encapsulated, hermetically sealed cathode capsule for generating an electron beam of secondary electrons, which generally includes a cathode element having a primary emission surface adapted to emit primary electrons, an annular insulating spacer, a diamond window element comprising a diamond material and having a secondary emission surface adapted to emit secondary electrons in response to primary electrons impinging on the diamond window element, a first cold-weld ring disposed between the cathode element and the annular insulating spacer and a second cold-weld ring disposed between the annular insulating spacer and the diamond window element. The cathode capsule is formed by a vacuum cold-weld process such that the first cold-weld ring forms a hermetical seal between the cathode element and the annular insulating spacer and the second cold-weld ring forms a hermetical seal between the annular spacer and the diamond window element whereby a vacuum encapsulated chamber is formed within the capsule.

  17. Engineering shallow spins in diamond with nitrogen delta-doping

    SciTech Connect (OSTI)

    Ohno, Kenichi; Joseph Heremans, F.; Bassett, Lee C.; Myers, Bryan A.; Toyli, David M.; Bleszynski Jayich, Ania C.; Palmstrom, Christopher J.; Awschalom, David D.

    2012-08-20

    We demonstrate nanometer-precision depth control of nitrogen-vacancy (NV) center creation near the surface of synthetic diamond using an in situ nitrogen delta-doping technique during plasma-enhanced chemical vapor deposition. Despite their proximity to the surface, doped NV centers with depths (d) ranging from 5 to 100 nm display long spin coherence times, T{sub 2} > 100 {mu}s at d = 5 nm and T{sub 2} > 600 {mu}s at d {>=} 50 nm. The consistently long spin coherence observed in such shallow NV centers enables applications such as atomic-scale external spin sensing and hybrid quantum architectures.

  18. Alignment of the diamond nitrogen vacancy center by strain engineering

    SciTech Connect (OSTI)

    Karin, Todd [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Dunham, Scott [Department of Electrical Engineering, University of Washington, Seattle, Washington 98195 (United States); Fu, Kai-Mei [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Department of Electrical Engineering, University of Washington, Seattle, Washington 98195 (United States)

    2014-08-04

    The nitrogen vacancy (NV) center in diamond is a sensitive probe of magnetic field and a promising qubit candidate for quantum information processing. The performance of many NV-based devices improves by aligning the NV(s) parallel to a single crystallographic direction. Using ab initio theoretical techniques, we show that NV orientation can be controlled by high-temperature annealing in the presence of strain under currently accessible experimental conditions. We find that (89?±?7)% of NVs align along the [111] crystallographic direction under 2% compressive biaxial strain (perpendicular to [111]) and an annealing temperature of 970?°C.

  19. Method and apparatus for making diamond-like carbon films

    DOE Patents [OSTI]

    Pern, Fu-Jann; Touryan, Kenell J.; Panosyan, Zhozef Retevos; Gippius, Aleksey Alekseyevich

    2008-12-02

    Ion-assisted plasma enhanced deposition of diamond-like carbon (DLC) films on the surface of photovoltaic solar cells is accomplished with a method and apparatus for controlling ion energy. The quality of DLC layers is fine-tuned by a properly biased system of special electrodes and by exact control of the feed gas mixture compositions. Uniform (with degree of non-uniformity of optical parameters less than 5%) large area (more than 110 cm.sup.2) DLC films with optical parameters varied within the given range and with stability against harmful effects of the environment are achieved.

  20. Charging characteritiscs of ultrananocrystalline diamond in RF MEMS capacitive switches.

    SciTech Connect (OSTI)

    Sumant, A. V.; Goldsmith, C.; Auciello, O.; Carlisle, J.; Zheng, H.; Hwang, J. C. M.; Palego, C.; Wang, W.; Carpick, R.; Adiga, V.; Datta, A.; Gudeman, C.; O'Brien, S.; Sampath, S.

    2010-05-01

    Modifications to a standard capacitive MEMS switch process have been made to allow the incorporation of ultra-nano-crystalline diamond as the switch dielectric. The impact on electromechanical performance is minimal. However, these devices exhibit uniquely different charging characteristics, with charging and discharging time constants 5-6 orders of magnitude quicker than conventional materials. This operation opens the possibility of devices which have no adverse effects of dielectric charging and can be operated near-continuously in the actuated state without significant degradation in reliability.

  1. Refractory two-dimensional hole gas on hydrogenated diamond surface

    SciTech Connect (OSTI)

    Hiraiwa, Atsushi; Daicho, Akira; Kurihara, Shinichiro; Yokoyama, Yuki; Kawarada, Hiroshi

    2012-12-15

    Use of two-dimensional hole gas (2DHG), induced on a hydrogenated diamond surface, is a solution to overcoming one of demerits of diamond, i.e., deep energy levels of impurities. This 2DHG is affected by its environment and accordingly needs a passivation film to get a stable device operation especially at high temperature. In response to this requirement, we achieved the high-reliability passivation forming an Al{sub 2}O{sub 3} film on the diamond surface using an atomic-layer-deposition (ALD) method with an H{sub 2}O oxidant at 450 Degree-Sign C. The 2DHG thus protected survived air annealing at 550 Degree-Sign C for an hour, establishing a stable high-temperature operation of 2DHG devices in air. In part, this achievement is based on high stability of C-H bonds up to 870 Degree-Sign C in vacuum and above 450 Degree-Sign C in an H{sub 2}O-containing environment as in the ALD. Chemically, this stability is supported by the fact that both the thermal decomposition of C-H bonds and reaction between C-H bonds and H{sub 2}O are endothermic processes. It makes a stark contrast to the instability of Si-H bonds, which decompose even at room temperature being exposed to atomic hydrogen. In this respect, the diamond 2DHG devices are also promising as power devices expectedly being free from many instability phenomena, such as hot carrier effect and negative-bias temperature instability, associated with Si devices. As to adsorbate, which is the other prerequisite for 2DHG, it desorbed in vacuum below 250 Degree-Sign C, and accordingly some new adsorbates should have adsorbed during the ALD at 450 Degree-Sign C. As a clue to this question, we certainly confirmed that some adsorbates, other than those at room temperature, adsorbed in air above 100 Degree-Sign C and remained at least up to 290 Degree-Sign C. The identification of these adsorbates is open for further investigation.

  2. TH-C-19A-06: Measurements with a New Commercial Synthetic Single Crystal Diamond Detector

    SciTech Connect (OSTI)

    Laub, W; Crilly, R

    2014-06-15

    Purpose: A commercial version of a synthetic single crystal diamond detector in a Scottky diode configuration was recently released as the new type 60019 microDiamond detector (PTW-Freiburg). In this study we investigate the dosimetric properties of this detector and explore if the use of the microDiamond detector can be expanded to high energy photon beams of up to 15MV and to large field measurements. Methods: Energy dependency was investigated. Photon and electron depth-dose curves were measured. Photon PDDs were measured with the Semiflex type 31010, microLion type 31018, P-Diode type 60016, SRS Diode type 60018, and the microDiamond type 60019 detector. Electron depth-dose curves were measured with a Markus chamber type 23343, an E Diode type 60017 and the microDiamond type 60019 detector (all PTW-Freiburg). Profiles were measured with the E-Diode and microDiamond at dose maximum depths. Results: The microDiamond detector shows no energy dependence in high energy photon or electron dosimetry. Electron PDD measurements with the E-Diode and microDiamond are in good agreement except for the bremsstrahlungs region, where values are about 0.5 % lower with the microDiamond detector. Markus detector measurements agree with E-Diode measurements in this region. For depths larger than dmax, depth-dose curves of photon beams measured with the microDiamond detector are in close agreement to those measured with the microLion detector for small fields and with those measured with a Semiflex 0.125cc ionization chamber for large fields. For profile measurements, microDiamond detector measurements agree well with microLion and P-Diode measurements in the high-dose region and the penumbra region. For areas outside the open field, P-Diode measurements are about 0.5–1.0% higher than microDiamond and microLion measurements. Conclusion: The investigated diamond detector is suitable for a wide range of applications in high energy photon and electron dosimetry and is interesting

  3. Mechanical stiffness and dissipation in ultrananocrystalline diamond micro-resonators.

    SciTech Connect (OSTI)

    Sumant, A. V.; Adiga, V. P.; Suresh, S.; Gudeman, C.; Auciello, O.; Carlis, J. A.; Carpick, R. W.

    2009-01-01

    We have characterized mechanical properties of ultrananocrystalline diamond (UNCD) thin films grown using the hot filament chemical vapor deposition (HFCVD) technique at 680 C, significantly lower than the conventional growth temperature of {approx}800 C. The films have {approx}4.3% sp{sup 2} content in the near-surface region as revealed by near edge x-ray absorption fine structure spectroscopy. The films, {approx}1 {micro}m thick, exhibit a net residual compressive stress of 370 {+-} 1 MPa averaged over the entire 150 mm wafer. UNCD microcantilever resonator structures and overhanging ledges were fabricated using lithography, dry etching, and wet release techniques. Overhanging ledges of the films released from the substrate exhibited periodic undulations due to stress relaxation. This was used to determine a biaxial modulus of 838 {+-} 2 GPa. Resonant excitation and ring-down measurements in the kHz frequency range of the microcantilevers were conducted under ultrahigh vacuum (UHV) conditions in a customized UHV atomic force microscope system to determine Young's modulus as well as mechanical dissipation of cantilever structures at room temperature. Young's modulus is found to be 790 {+-} 30 GPa. Based on these measurements, Poisson's ratio is estimated to be 0.057 {+-} 0.038. The quality factors (Q) of these resonators ranged from 5000 to 16000. These Q values are lower than theoretically expected from the intrinsic properties of diamond. The results indicate that surface and bulk defects are the main contributors to the observed dissipation in UNCD resonators.

  4. 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.

  5. Large-area low-temperature ultrananocrystaline diamond (UNCD) films and integration with CMOS devices for monolithically integrated diamond MEMD/NEMS-CMOS systems.

    SciTech Connect (OSTI)

    Sumant, A.V.; Auciello, O.; Yuan, H.-C; Ma, Z.; Carpick, R. W.; Mancini, D. C.; Univ. of Wisconsin; Univ. of Pennsylvania

    2009-05-01

    Because of exceptional mechanical, chemical, and tribological properties, diamond has a great potential to be used as a material for the development of high-performance MEMS and NEMS such as resonators and switches compatible with harsh environments, which involve mechanical motion and intermittent contact. Integration of such MEMS/NEMS devices with complementary metal oxide semiconductor (CMOS) microelectronics will provide a unique platform for CMOS-driven commercial MEMS/NEMS. The main hurdle to achieve diamond-CMOS integration is the relatively high substrate temperatures (600-800 C) required for depositing conventional diamond thin films, which are well above the CMOS operating thermal budget (400 C). Additionally, a materials integration strategy has to be developed to enable diamond-CMOS integration. Ultrananocrystalline diamond (UNCD), a novel material developed in thin film form at Argonne, is currently the only microwave plasma chemical vapor deposition (MPCVD) grown diamond film that can be grown at 400 C, and still retain exceptional mechanical, chemical, and tribological properties comparable to that of single crystal diamond. We have developed a process based on MPCVD to synthesize UNCD films on up to 200 mm in diameter CMOS wafers, which will open new avenues for the fabrication of monolithically integrated CMOS-driven MEMS/NEMS based on UNCD. UNCD films were grown successfully on individual Si-based CMOS chips and on 200 mm CMOS wafers at 400 C in a MPCVD system, using Ar-rich/CH4 gas mixture. The CMOS devices on the wafers were characterized before and after UNCD deposition. All devices were performing to specifications with very small degradation after UNCD deposition and processing. A threshold voltage degradation in the range of 0.08-0.44V and transconductance degradation in the range of 1.5-9% were observed.

  6. Thin film circuit fabrication on diamond substrates for high power applications

    SciTech Connect (OSTI)

    Norwood, D.; Worobey, W.; Peterson, D.; Sweet, J.; Johnson, D.; Miller, D.; Andaleon, D.

    1995-05-01

    Sandia Laboratories has developed a thin film diamond substrate technology to meet the requirements for high power and high density circuits. Processes were developed to metallize, photopattern, laser process, and, package diamond thin film networks which were later assembled into high power multichip modules (MCMS) to test for effectiveness at removing heat. Diamond clearly demonstrated improvement in heat transfer during 20 Watt, strip heating experiments with junction-to-ambient temperature increases of less than 24 C compared to 126 C and 265 C for the aluminum nitride and ceramic versions, respectively.

  7. Adhesion of diamond coatings synthesized by oxygen-acetylene flame CVD on tungsten carbide

    SciTech Connect (OSTI)

    Marinkovic, S.; Stankovic, S.; Dekanski, A.

    1995-12-31

    The results of a study concerned with chemical vapor deposition of diamond on tungsten carbide cutting tools using an oxygen-acetylene flame in a normal ambient environment are presented. Effects of preparation conditions on the adhesion of the coating have been investigated, including different surface treatment, different position of the flame with respect to the coated surface, effect of an intermediate poorly crystalline diamond layer, etc. In particular, effect of polishing and ultrasonic lapping with diamond powder was compared with that of a corresponding treatment with SiC powder.

  8. Optically transparent, scratch-resistant, diamond-like carbon coatings

    DOE Patents [OSTI]

    He, Xiao-Ming; Lee, Deok-Hyung; Nastasi, Michael A.; Walter, Kevin C.; Tuszewski, Michel G.

    2003-06-03

    A plasma-based method for the deposition of diamond-like carbon (DLC) coatings is described. The process uses a radio-frequency inductively coupled discharge to generate a plasma at relatively low gas pressures. The deposition process is environmentally friendly and scaleable to large areas, and components that have geometrically complicated surfaces can be processed. The method has been used to deposit adherent 100-400 nm thick DLC coatings on metals, glass, and polymers. These coatings are between three and four times harder than steel and are therefore scratch resistant, and transparent to visible light. Boron and silicon doping of the DLC coatings have produced coatings having improved optical properties and lower coating stress levels, but with slightly lower hardness.

  9. Submicron cubic boron nitride as hard as diamond

    SciTech Connect (OSTI)

    Liu, Guoduan; Kou, Zili E-mail: yanxz@hpstar.ac.cn; Lei, Li; Peng, Fang; Wang, Qiming; Wang, Kaixue; Wang, Pei; Li, Liang; Li, Yong; Wang, Yonghua; Yan, Xiaozhi E-mail: yanxz@hpstar.ac.cn; Li, Wentao; Bi, Yan; Leng, Yang; He, Duanwei

    2015-03-23

    Here, we report the sintering of aggregated submicron cubic boron nitride (sm-cBN) at a pressure of 8 GPa. The sintered cBN compacts exhibit hardness values comparable to that of single crystal diamond, fracture toughness about 5-fold that of cBN single crystal, in combination with a high oxidization temperature. Thus, another way has been demonstrated to improve the mechanical properties of cBN besides reducing the grain size to nano scale. In contrast to other ultrahard compacts with similar hardness, the sm-cBN aggregates are better placed for potential industrial application, as their relative low pressure manufacturing perhaps be easier and cheaper.

  10. Nucleation of nanocrystalline diamond by fragmentation of fullerene precursors.

    SciTech Connect (OSTI)

    Gruen, D. M.

    1998-05-04

    Growth of diamond films from C{sub 60}/Ar microwave discharges results in a nanocrystalline microstructure with crystallite sizes in the range 3-10 nm. Heterogeneous nucleation rates of 10{sup 10} cm{sup {minus}2} sec are required to account for the results. The nucleation mechanism presented here fulfills this requirement and is based on the insertion of carbon dimer, C{sub 2}, molecules, produced by fragmentation of C{sub 60}, into the n-bonded dimer rows of the reconstructed (100) surface of diamond. Density functional theory is used to calculate the energetic of C{sub 2} insertion into carbon clusters that model the (100) surface. The reaction of singlet C{sub 2} with the double bond of the C{sub 9}H{sub 12} cluster leads to either carbene structures or a cyclobutynelike structure. At the HF/6-31G* level, the carbene product has a C{sub 2v} structure, while at the B3LYP/6-31G* levels of theory, it has a C{sub s} structure with the inserted C{sub 2} tilted. No barrier for insertion into the C=C double bond of the C{sub 9}H{sub 12} cluster was found at the HF/6-31G* and B3LYP/6-31G* levels of theory. Thus, calculations including correlation energy and geometry optimization indicate that insertion of C{sub 2} into a C=C double bond leads to a large energy lowering, {approximately}120 kcal/mol for a C{sub 9}H{sub 12} cluster, and there is no barrier for insertion.

  11. A photoemission study of the diamond and the single crystal C{sub 60}

    SciTech Connect (OSTI)

    Wu, Jin

    1994-03-01

    This report studied the elctronic structure of diamond (100) and diamond/metal interface and C{sub 60}, using angle-resolved and core level photoemission. The C(100)-(2X1) surface electronic structure was studied using both core level and angle resolved valence band photoemission spectroscopy. The surface component of the C 1s core level spectrum agrees with theoretical existence of only symmetrical dimers. In the case of metal/diamond interfaces, core level and valence photoelectron spectroscopy and LEED studies WERE MADE OF B and Sb on diamond (100) and (111) surfaces. In the case of single-crystal C{sub 60}, photoemission spectra show sharp molecular features, indicating that the molecular orbitals are relatively undisturbed in solid C{sub 60}.

  12. Ramp Compression of Diamond at 5 TPa (Journal Article) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Ramp Compression of Diamond at 5 TPa Authors: Smith, R F ; Eggert, J H ; Jeanloz, R ; Duffy, T S ; Braun, D G ; Patterson, J R ; Rudd, R ...

  13. Electrochemically grafted polypyrrole changes photoluminescence of electronic states inside nanocrystalline diamond

    SciTech Connect (OSTI)

    Galá?, P. Malý, P.; ?ermák, J.; Kromka, A.; Rezek, B.

    2014-12-14

    Hybrid diamond-organic interfaces are considered attractive for diverse applications ranging from electronics and energy conversion to medicine. Here we use time-resolved and time-integrated photoluminescence spectroscopy in visible spectral range (380–700?nm) to study electronic processes in H-terminated nanocrystalline diamond films (NCD) with 150?nm thin, electrochemically deposited polypyrrole (PPy) layer. We observe changes in dynamics of NCD photoluminescence as well as in its time-integrated spectra after polymer deposition. The effect is reversible. We propose a model where the PPy layer on the NCD surface promotes spatial separation of photo-generated charge carriers both in non-diamond carbon phase and in bulk diamond. By comparing different NCD thicknesses we show that the effect goes as much as 200?nm deep inside the NCD film.

  14. Preparation of W-Ta thin-film thermocouple on diamond anvil cell...

    Office of Scientific and Technical Information (OSTI)

    Preparation of W-Ta thin-film thermocouple on diamond anvil cell for in-situ temperature measurement under high pressure Citation Details In-Document Search Title: Preparation of W...

  15. The semi-empirical tight-binding model for carbon allotropes “between diamond and graphite”

    SciTech Connect (OSTI)

    Lytovchenko, V.; Kurchak, A.; Strikha, M.

    2014-06-28

    The new carbon allotropes “between diamond and graphite” have come under intensive examination during the last decade due to their numerous technical applications. The modification of energy gap in thin films of these allotropes was studied experimentally using optical methods. The proposed simple model of carbon clusters with variable lengths of chemical bonds allows us to imitate the transfer from diamond and diamond-like to graphite-like structures, as well as the corresponding modification of hybridization sp{sup 3}/sp{sup 2} for diamond-like and sp{sub z} for graphite-like phases. This enables us to estimate various allotropes parameters, like the gap E{sub g}, energies of valence E{sub v}, and conduction E{sub c} band edges, and the value of electronic affinity, i.e., optical work function X, which are all of practical importance. The obtained estimations correspond to the experimental data.

  16. Diamonds help generate new record for static pressures for study | Argonne

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

    National Laboratory A double-stage diamond anvil cell mounted at the beamline at the Advanced Photon Source. (Image courtesy Vitali Prakapenka) A double-stage diamond anvil cell mounted at the beamline at the Advanced Photon Source. (Image courtesy Vitali Prakapenka) University of Bayreuth scientist and study co-author Leonid Dubrovinsky at the beamline. (Image courtesy Vitali Prakapenka) University of Bayreuth scientist and study co-author Leonid Dubrovinsky at the beamline. (Image courtesy

  17. Dented Diamonds, Carbon Cages and Exceptional Potential | U.S. DOE Office

    Office of Science (SC) Website

    of Science (SC) Dented Diamonds, Carbon Cages and Exceptional Potential News News Home Featured Articles 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 Science Headlines Science Highlights Presentations & Testimony News Archives Communications and Public Affairs Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 08.27.12 Dented Diamonds, Carbon Cages and Exceptional Potential Office of Science

  18. Carbon atom, dimer and trimer chemistry on diamond surfaces from molecular dynamics simulations

    SciTech Connect (OSTI)

    Valone, S.M.

    1995-07-01

    Spectroscopic studies of various atmospheres appearing in diamond film synthesis suggest evidence for carbon atoms, dimers, or trimers. Molecular dynamics simulations with the Brenner hydrocarbon potential are being used to investigate the elementary reactions of these species on a hydrogen-terminated diamond (111) surface. In principle these types of simulations can be extended to simulations of growth morphologies, in the 1-2 monolayer regime presently.

  19. GaN-on-diamond electronic device reliability: Mechanical and thermo-mechanical integrity

    SciTech Connect (OSTI)

    Liu, Dong; Sun, Huarui; Pomeroy, James W.; Kuball, Martin; Francis, Daniel; Faili, Firooz; Twitchen, Daniel J.

    2015-12-21

    The mechanical and thermo-mechanical integrity of GaN-on-diamond wafers used for ultra-high power microwave electronic devices was studied using a micro-pillar based in situ mechanical testing approach combined with an optical investigation of the stress and heat transfer across interfaces. We find the GaN/diamond interface to be thermo-mechanically stable, illustrating the potential for this material for reliable GaN electronic devices.

  20. Note: Laser ablation technique for electrically contacting a buried implant layer in single crystal diamond

    SciTech Connect (OSTI)

    Ray, M. P.; Baldwin, J. W.; Butler, J. E.; Pate, B. B.; Feygelson, T. I.

    2011-05-15

    The creation of thin, buried, and electrically conducting layers within an otherwise insulating diamond by annealed ion implantation damage is well known. Establishing facile electrical contact to the shallow buried layer has been an unmet challenge. We demonstrate a new method, based on laser micro-machining (laser ablation), to make reliable electrical contact to a buried implant layer in diamond. Comparison is made to focused ion beam milling.

  1. Self-healing diamond-like carbon coating could revolutionize lubrication |

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

    Argonne National Laboratory Self-healing diamond-like carbon coating could revolutionize lubrication Share Description Argonne scientists discovered a technique to create a layer of diamond-like carbon on the surfaces between moving parts. This could change the future of lubrication-potentially making engines more efficient, more reliable, and even greener (by reducing heavy metal additives needed in engine oils.) Duration 0:45 Topic Energy Energy efficiency Manufacturing Credit Argonne

  2. Self-healing diamond-like carbon coating could revolutionize lubrication |

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

    Argonne National Laboratory Self-healing diamond-like carbon coating could revolutionize lubrication Share Description Argonne scientists discovered a technique to create a layer of diamond-like carbon on the surfaces between moving parts. This could change the future of lubrication-potentially making engines more efficient, more reliable, and even greener (by reducing heavy metal additives needed in engine oils.) Duration 0:45 Credit Argonne National Laboratory Browse By - Any - General

  3. Diamond formation due to a pH drop during fluid–rock interactions

    SciTech Connect (OSTI)

    Sverjensky, Dimitri A.; Huang, Fang

    2015-11-03

    Diamond formation has typically been attributed to redox reactions during precipitation from fluids or magmas. Either the oxidation of methane or the reduction of carbon dioxide has been suggested, based on simplistic models of deep fluids consisting of mixtures of dissolved neutral gas molecules without consideration of aqueous ions. The role of pH changes associated with water–silicate rock interactions during diamond formation is unknown. Here we show that diamonds could form due to a drop in pH during water–rock interactions. We use a recent theoretical model of deep fluids that includes ions, to show that fluid can react irreversibly with eclogite at 900 °C and 5.0 GPa, generating diamond and secondary minerals due to a decrease in pH at almost constant oxygen fugacity. Overall, our results constitute a new quantitative theory of diamond formation as a consequence of the reaction of deep fluids with the rock types that they encounter during migration. Diamond can form in the deep Earth during water–rock interactions without changes in oxidation state.

  4. Diamond formation due to a pH drop during fluid–rock interactions

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

    Sverjensky, Dimitri A.; Huang, Fang

    2015-11-03

    Diamond formation has typically been attributed to redox reactions during precipitation from fluids or magmas. Either the oxidation of methane or the reduction of carbon dioxide has been suggested, based on simplistic models of deep fluids consisting of mixtures of dissolved neutral gas molecules without consideration of aqueous ions. The role of pH changes associated with water–silicate rock interactions during diamond formation is unknown. Here we show that diamonds could form due to a drop in pH during water–rock interactions. We use a recent theoretical model of deep fluids that includes ions, to show that fluid can react irreversibly withmore » eclogite at 900 °C and 5.0 GPa, generating diamond and secondary minerals due to a decrease in pH at almost constant oxygen fugacity. Overall, our results constitute a new quantitative theory of diamond formation as a consequence of the reaction of deep fluids with the rock types that they encounter during migration. Diamond can form in the deep Earth during water–rock interactions without changes in oxidation state.« less

  5. Nanosecond formation of diamond and lonsdaleite by shock compression of graphite

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

    Kraus, D.; Ravasio, A.; Gauthier, M.; Gericke, D. O.; Vorberger, J.; Frydrych, S.; Helfrich, J.; Fletcher, L. B.; Schaumann, G.; Nagler, B.; et al

    2016-03-14

    Here, the shock-induced transition from graphite to diamond has been of great scientific and technological interest since the discovery of microscopic diamonds in remnants of explosively driven graphite. Furthermore, shock synthesis of diamond and lonsdaleite, a speculative hexagonal carbon polymorph with unique hardness, is expected to happen during violent meteor impacts. Here, we show unprecedented in situ X-ray diffraction measurements of diamond formation on nanosecond timescales by shock compression of pyrolytic as well as polycrystalline graphite to pressures from 19 GPa up to 228 GPa. While we observe the transition to diamond starting at 50 GPa for both pyrolytic andmore » polycrystalline graphite, we also record the direct formation of lonsdaleite above 170 GPa for pyrolytic samples only. Our experiment provides new insights into the processes of the shock-induced transition from graphite to diamond and uniquely resolves the dynamics that explain the main natural occurrence of the lonsdaleite crystal structure being close to meteor impact sites.« less

  6. Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

    SciTech Connect (OSTI)

    Kagan, Harris; Kass, Richard; Gan, K.K.

    2014-01-23

    With the LHC upgrades in 2013, and further LHC upgrades scheduled in 2018, most LHC experiments are planning for detector upgrades which require more radiation hard technologies than presently available. At present all LHC experiments now have some form of diamond detector. As a result Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of all LHC experiments. Moreover CVD diamond is now being discussed as an alternative sensor material for tracking very close to the interaction region of the HL-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications. Our accomplishments include: • Developed a two U.S.companies to produce electronic grade diamond, • Worked with companies and acquired large area diamond pieces, • Performed radiation hardness tests using various proton energies: 70 MeV (Cyric, Japan), 800 MeV (Los Alamos), and 24 GeV (CERN).

  7. A novel Mo-W interlayer approach for CVD diamond deposition on steel

    SciTech Connect (OSTI)

    Kundrát, Vojtěch; Sullivan, John; Ye, Haitao; Zhang, Xiaoling; Cooke, Kevin; Sun, Hailin

    2015-04-15

    Steel is the most widely used material in engineering for its cost/performance ratio and coatings are routinely applied on its surface to further improve its properties. Diamond coated steel parts are an option for many demanding industrial applications through prolonging the lifetime of steel parts, enhancement of tool performance as well as the reduction of wear rates. Direct deposition of diamond on steel using conventional chemical vapour deposition (CVD) processes is known to give poor results due to the preferential formation of amorphous carbon on iron, nickel and other elements as well as stresses induced from the significant difference in the thermal expansion coefficients of those materials. This article reports a novel approach of deposition of nanocrystalline diamond coatings on high-speed steel (M42) substrates using a multi-structured molybdenum (Mo) – tungsten (W) interlayer to form steel/Mo/Mo-W/W/diamond sandwich structures which overcome the adhesion problem related to direct magnetron sputtering deposition of pure tungsten. Surface, interface and tribology properties were evaluated to understand the role of such an interlayer structure. The multi-structured Mo-W interlayer has been proven to improve the adhesion between diamond films and steel substrates by acting as an effective diffusion barrier during the CVD diamond deposition.

  8. Adsorptive Separation and Sequestration of Krypton, I and C14 on Diamond Nanoparticles

    SciTech Connect (OSTI)

    Ghosh, Tushar; Loyalka, Sudarsha; Prelas, Mark; Viswanath, Dabir

    2015-03-31

    The objective of this research proposal was to address the separation and sequestration of Kr and I from each other using nano-sized diamond particles and retaining these in diamond until they decay to the background level or can be used as a byproduct. Following removal of Kr and I, an adsorbent will be used to adsorb and store CO2 from the CO2 rich stream. A Field Enhanced Diffusion with Optical Activation (FEDOA-a large scale process that takes advantage of thermal, electrical, and optical activation to enhance the diffusion of an element into diamond structure) was used to load Kr and I on micron or nano sized particles having a larger relative surface area. The diamond particles can be further increased by doping it with boron followed by irradiation in a neutron flux. Previous studies showed that the hydrogen storage capacity could be increased significantly by using boron-doped irradiated diamond particles. Diamond powders were irradiated for a longer time by placing them in a quartz tube. The surface area was measured using a Quantachrome Autosorb system. No significant increase in the surface area was observed. Total surface area was about 1.7 m2/g. This suggests the existence of very minimal pores. Interestingly it showed hysteresis upon desorption. A reason for this may be strong interaction between the surface and the nitrogen molecules. Adsorption runs at higher temperatures did not show any adsorption of krypton on diamond. Use of a GC with HID detector to determine the adsorption capacity from the breakthrough curves was attempted, but experimental difficulties were encountered.

  9. Science and technology of ultrananocrystalline diamond (UNCD) thin films for multifunctional devices

    SciTech Connect (OSTI)

    Auciello, O.; Krauss, A. R.; Gruen, D. M.; Jayatissa, A.; Sumant, A.; Tucek, J.; Mancini, D.; Molodvan, N.; Erdemir, A.; Ersoy, D.; Gardos, M. N.; Busman, H. G.; Meyer, E. M.

    2000-08-24

    MEMS devices are currently fabricated primarily in silicon because of the available surface machining technology. However, Si has poor mechanical and tribological properties, and practical MEMS devices are currently limited primarily to applications involving only bending and flexural motion, such as cantilever accelerometers and vibration sensors. However, because of the poor flexural strength and fracture toughness of Si, and the tendency of Si to adhere to hydrophyllic surfaces, even these simple devices have limited dynamic range. Future MEMS applications that involve significant rolling or sliding contact will require the use of new materials with significantly improved mechanical and tribological properties, and the ability to perform well in harsh environments. Diamond is a superhard material of high mechanical strength, exceptional chemical inertness, and outstanding thermal stability. The brittle fracture strength is 23 times that of Si, and the projected wear life of diamond MEMS moving mechanical assemblies (MEMS-MMAs) is 10,000 times greater than that of Si MMAs. However, as the hardest known material, diamond is notoriously difficult to fabricate. Conventional CVD thin film deposition methods offer an approach to the fabrication of ultra-small diamond structures, but the films have large grain size, high internal stress, poor intergranular adhesion, and very rough surfaces, and are consequently ill-suited for MEMS-MMA applications. A thin film deposition process has been developed that produces phase-pure nanocrystalline diamond with morphological and mechanical properties that are ideally suited for MEMS applications in general, and MMA use in particular. The authors have developed lithographic techniques for the fabrication of diamond microstructure including cantilevers and multi-level devices, acting as precursors to micro-bearings and gears, making nanocrystalline diamond a promising material for the development of high performance MEMS devices.

  10. Modeling electron emission and surface effects from diamond cathodes

    SciTech Connect (OSTI)

    Dimitrov, D. A.; Smithe, D.; Cary, J. R.; Ben-Zvi, I.; Rao, T.; Smedley, J.; Wang, E.

    2015-02-05

    We developed modeling capabilities, within the Vorpal particle-in-cell code, for three-dimensional (3D) simulations of surface effects and electron emission from semiconductor photocathodes. They include calculation of emission probabilities using general, piece-wise continuous, space-time dependent surface potentials, effective mass and band bending field effects. We applied these models, in combination with previously implemented capabilities for modeling charge generation and transport in diamond, to investigate the emission dependence on applied electric field in the range from approximately 2 MV/m to 17 MV/m along the [100] direction. The simulation results were compared to experimental data. For the considered parameter regime, conservation of transverse electron momentum (in the plane of the emission surface) allows direct emission from only two (parallel to [100]) of the six equivalent lowest conduction band valleys. When the electron affinity χ is the only parameter varied in the simulations, the value χ = 0.31 eV leads to overall qualitative agreement with the probability of emission deduced from experiments. Including band bending in the simulations improves the agreement with the experimental data, particularly at low applied fields, but not significantly. In this study, using surface potentials with different profiles further allows us to investigate the emission as a function of potential barrier height, width, and vacuum level position. However, adding surface patches with different levels of hydrogenation, modeled with position-dependent electron affinity, leads to the closest agreement with the experimental data.

  11. Modeling electron emission and surface effects from diamond cathodes

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

    Dimitrov, D. A.; Smithe, D.; Cary, J. R.; Ben-Zvi, I.; Rao, T.; Smedley, J.; Wang, E.

    2015-02-05

    We developed modeling capabilities, within the Vorpal particle-in-cell code, for three-dimensional (3D) simulations of surface effects and electron emission from semiconductor photocathodes. They include calculation of emission probabilities using general, piece-wise continuous, space-time dependent surface potentials, effective mass and band bending field effects. We applied these models, in combination with previously implemented capabilities for modeling charge generation and transport in diamond, to investigate the emission dependence on applied electric field in the range from approximately 2 MV/m to 17 MV/m along the [100] direction. The simulation results were compared to experimental data. For the considered parameter regime, conservation of transversemore » electron momentum (in the plane of the emission surface) allows direct emission from only two (parallel to [100]) of the six equivalent lowest conduction band valleys. When the electron affinity χ is the only parameter varied in the simulations, the value χ = 0.31 eV leads to overall qualitative agreement with the probability of emission deduced from experiments. Including band bending in the simulations improves the agreement with the experimental data, particularly at low applied fields, but not significantly. In this study, using surface potentials with different profiles further allows us to investigate the emission as a function of potential barrier height, width, and vacuum level position. However, adding surface patches with different levels of hydrogenation, modeled with position-dependent electron affinity, leads to the closest agreement with the experimental data.« less

  12. Diamond detector for high rate monitors of fast neutrons beams

    SciTech Connect (OSTI)

    Giacomelli, L.; Rebai, M.; Cippo, E. Perelli; Tardocchi, M.; Fazzi, A.; Andreani, C.; Pietropaolo, A.; Frost, C. D.; Rhodes, N.; Schooneveld, E.; Gorini, G.

    2012-06-19

    A fast neutron detection system suitable for high rate measurements is presented. The detector is based on a commercial high purity single crystal diamond (SDD) coupled to a fast digital data acquisition system. The detector was tested at the ISIS pulsed spallation neutron source. The SDD event signal was digitized at 1 GHz to reconstruct the deposited energy (pulse amplitude) and neutron arrival time; the event time of flight (ToF) was obtained relative to the recorded proton beam signal t{sub 0}. Fast acquisition is needed since the peak count rate is very high ({approx}800 kHz) due to the pulsed structure of the neutron beam. Measurements at ISIS indicate that three characteristics regions exist in the biparametric spectrum: i) background gamma events of low pulse amplitudes; ii) low pulse amplitude neutron events in the energy range E{sub dep}= 1.5-7 MeV ascribed to neutron elastic scattering on {sup 12}C; iii) large pulse amplitude neutron events with E{sub n} < 7 MeV ascribed to {sup 12}C(n,{alpha}){sup 9}Be and 12C(n,n')3{alpha}.

  13. The Nanoscience Beamline (I06) at Diamond Light Source

    SciTech Connect (OSTI)

    Dhesi, S. S.; Cavill, S. A.; Potenza, A.; Marchetto, H.; Mott, R. A.; Steadman, P.; Peach, A.; Shepherd, E. L.; Ren, X.; Wagner, U. H.; Reininger, R.

    2010-06-23

    The Nanoscience beamline (I06) is one of seven Diamond Phase-I beamlines which has been operational since January 2007 delivering polarised soft x-rays, for a PhotoEmission Electron Microscope (PEEM) and branchline, in the energy range 80-2100 eV. The beamline is based on a collimated plane grating monochromator with sagittal focusing elements, utilising two APPLE II helical undulator sources, and has been designed for high flux density at the PEEM sample position. A {approx}5 {mu}m ({sigma}) diameter beam is focussed onto the sample in the PEEM allowing a range of experiments using x-ray absorption spectroscopy (XAS), x-ray magnetic circular dichroism (XMCD) and x-ray magnetic linear dichroism (XMLD) as contrast mechanisms. The beamline is also equipped with a branchline housing a 6T superconducting magnet for XMCD and XMLD experiments. The magnet is designed to move on and off the branchline which allows a diverse range of experiments.

  14. Diamond Wire Cutting of the Tokamak Fusion Test Reactor

    SciTech Connect (OSTI)

    Keith Rule; Erik Perry; Robert Parsells

    2003-01-31

    The Tokamak Fusion Test Reactor (TFTR) is a one-of-a-kind, tritium-fueled fusion research reactor that ceased operation in April 1997. As a result, decommissioning commenced in October 1999. The 100 cubic meter volume of the donut-shaped reactor makes it the second largest fusion reactor in the world. The deuterium-tritium experiments resulted in contaminating the vacuum vessel with tritium and activating the materials with 14 MeV neutrons. The total tritium content within the vessel is in excess of 7,000 Curies, while dose rates approach 50 mRem/hr. These radiological hazards along with the size of the tokamak present a unique and challenging task for dismantling. Engineers at the Princeton Plasma Physics Laboratory (PPPL) decided to investigate an alternate, innovative approach for dismantlement of the TFTR vacuum vessel: diamond wire cutting technology. In August 1999, this technology was successfully demonstrated and evaluated on vacuum vessel surrogates. Subsequently, the technology was improved and redesigned for the actual cutting of the vacuum vessel. Ten complete cuts were performed in a 6-month period to complete the removal of this unprecedented type of D&D (Decontamination and Decommissioning) activity.

  15. DIAMOND WIRE CUTTING OF THE TOKAMAK FUSION TEST REACTOR

    SciTech Connect (OSTI)

    Rule, Keith; Perry, Erik; Parsells, Robert

    2003-02-27

    The Tokamak Fusion Test Reactor (TFTR) is a one-of-a-kind, tritium-fueled fusion research reactor that ceased operation in April 1997. As a result, decommissioning commenced in October 1999. The 100 cubic meter volume of the donut-shaped reactor makes it the second largest fusion reactor in the world. The deuterium-tritium experiments resulted in contaminating the vacuum vessel with tritium and activating the materials with 14 Mev neutrons. The total tritium content within the vessel is in excess of 7,000 Curies while dose rates approach 50 mRem/hr. These radiological hazards along with the size of the Tokamak present a unique and challenging task for dismantling. Engineers at the Princeton Plasma Physics Laboratory (PPPL) decided to investigate an alternate, innovative approach for dismantlement of the TFTR vacuum vessel: diamond wire cutting technology. In August 1999, this technology was successfully demonstrated and evaluated on vacuum vessel surrogates. Subsequently, the techno logy was improved and redesigned for the actual cutting of the vacuum vessel. 10 complete cuts were performed in a 6-month period to complete the removal of this unprecedented type of D&D activity.

  16. Diamond-anvil high-pressure cell with improved X-ray collimation system

    DOE Patents [OSTI]

    Schiferl, David; Olinger, Barton W.; Livingston, Robert W.

    1986-01-01

    An adjustable X-ray collimation system for a diamond-anvil high-pressure cell of the type including a cooperable piston and cylinder and a pair of opposing diamonds located between the head of the piston and the head of the cylinder. The X-ray collimation system includes a tubular insert which contains an X-ray collimator. The insert is engageable in the bore of the piston. The collimator is mounted within the insert by means of an elastomeric O-ring at the end closest the opposed diamonds, and by means of a set of adjustable set screws at the opposite end. By adjustment of the set screws the collimator can be pivoted about the O-ring and brought into alignment with the opposed diamonds and the sample contained therein. In the preferred embodiment there is further provided a set of plugs which are insertable in the bore of the collimator. The plugs have bores of different diameters. By successively inserting plugs of progressively smaller bore diameters and adjusting the alignment of the collimator with each plug, the collimator can be quickly brought into accurate alignment with the diamonds. The collimation system allows alignment of the collimator either before or after the cell has been loaded and pressurized.

  17. Diamond-anvil high-pressure cell with improved x-ray collimation system

    DOE Patents [OSTI]

    Schiferl, D.; Olinger, B.W.; Livingston, R.W.

    1984-03-30

    An adjustable x-ray collimation system for a diamond-anvil high-pressure cell of the type including a cooperable piston and cylinder and a pair of opposing diamonds located between the head of the piston and the head of the cylinder. The x-ray collimation system includes a tubular insert which contains an x-ray collimator. The insert is engageable in the bore of the piston. The collimator is mounted within the insert by means of an elastomeric o-ring at the end closest the opposed diamonds, and by means of a set of adjustable set screws at the opposite end. By adjustment of the set screws the collimator can be pivoted about the o-ring and brought into alignment with the opposed diamonds and the sample contained therein. In the preferred embodiment there is further provided a set of plugs which are insertable in the bore of the collimator. The plugs have bores of different diameters. By successively inserting plugs of progressively smaller bore diameters and adjusting the alignment of the collimator with each plug, the collimator can be quickly brought into accurate alignment with the diamonds. The collimation system allows alignment of the collimator either before or after the cell has been loaded and pressurized.

  18. Diamond and Hydrogenated Carbons for Advanced Batteries and Fuel Cells: Fundamental Studies and Applications.

    SciTech Connect (OSTI)

    Swain; Greg M.

    2009-04-13

    The original funding under this project number was awarded for a period 12/1999 until 12/2002 under the project title Diamond and Hydrogenated Carbons for Advanced Batteries and Fuel Cells: Fundamental Studies and Applications. The project was extended until 06/2003 at which time a renewal proposal was awarded for a period 06/2003 until 06/2008 under the project title Metal/Diamond Composite Thin-Film Electrodes: New Carbon Supported Catalytic Electrodes. The work under DE-FG02-01ER15120 was initiated about the time the PI moved his research group from the Department of Chemistry at Utah State University to the Department of Chemistry at Michigan State University. This DOE-funded research was focused on (i) understanding structure-function relationships at boron-doped diamond thin-film electrodes, (ii) understanding metal phase formation on diamond thin films and developing electrochemical approaches for producing highly dispersed electrocatalyst particles (e.g., Pt) of small nominal particle size, (iii) studying the electrochemical activity of the electrocatalytic electrodes for hydrogen oxidation and oxygen reduction and (iv) conducting the initial synthesis of high surface area diamond powders and evaluating their electrical and electrochemical properties when mixed with a Teflon binder.

  19. Fabrication of layered self-standing diamond film by dc arc plasma jet chemical vapor deposition

    SciTech Connect (OSTI)

    Chen, G. C.; Dai, F. W.; Li, B.; Lan, H.; Askari, J.; Tang, W. Z.; Lu, F. X.

    2007-01-15

    Layered self-standing diamond films, consisting of an upper layer, buffer layer, and a lower layer, were fabricated by fluctuating the ratio of methane to hydrogen in high power dc arc plasma jet chemical vapor deposition. There were micrometer-sized columnar diamond crystalline grains in both upper layer and lower layer. The size of the columnar diamond crystalline grains was bigger in the upper layer than that in the lower layer. The orientation of the upper layer was (110), while it was (111) for the lower layer. Raman results showed that no sp{sup 3} peak shift was found in the upper layer, but it was found and blueshifted in the lower layer. This indicated that the internal stress within the film body could be tailored by this layered structure. The buffer layer with nanometer-sized diamond grains formed by secondary nucleation was necessary in order to form the layered film. Growth rate was over 10 {mu}m/h in layered self-standing diamond film fabrication.

  20. Science and technology of piezoelectric/diamond heterostructures for monolithically integrated high performance MEMS/NEMS/CMOS devices.

    SciTech Connect (OSTI)

    Auciello, O.; Sumant, A. V.; Hiller, J.; Kabius, B.; Ma, Z.; Srinivasan, S.

    2008-12-01

    This paper describes the fundamental and applied science performed to integrate piezoelectric PbZr{sub x}Ti{sub 1-x}O{sub 3} and AlN films with a novel mechanically robust ultrananocrystalline diamond layer to enable a new generation of low voltage/high-performance piezoactuated hybrid piezoelectric/diamond MEMS/NEMS devices.

  1. Surprising stability of neutral interstitial hydrogen in diamond and cubic BN

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

    Lyons, J. L.; Van de Walle, C. G.

    2016-01-21

    We report that in virtually all semiconductors and insulators, hydrogen interstitials (Hi) act as negative-U centers, implying that hydrogen is never stable in the neutral charge state. Using hybrid density functional calculations, we find a different behavior for Hi in diamond and cubic BN. In diamond, Hi is a very strong positive-U center, and the H0icharge state is stable over a Fermi-level range of more than 2 eV. In cubic BN, a III-V compound similar to diamond, we also find positive-U behavior, though over a much smaller Fermi-level range. Finally, these results highlight the unique behavior of Hi in thesemore » covalent wide-band-gap semiconductors.« less

  2. Pressure, stress, and strain distribution in the double-stage diamond anvil cell

    SciTech Connect (OSTI)

    Lobanov, Sergey S.; Prakapenka, Vitali B.; Prescher, Clemens; Konôpková, Zuzana; Liermann, Hanns-Peter; Crispin, Katherine L.; Zhang, Chi; Goncharov, Alexander F.

    2015-07-21

    Double stage diamond anvil cells (DACs) of two designs have been assembled and tested. We used a standard symmetric DAC with flat or beveled culets as a primary stage and CVD microanvils machined by a focused ion beam as a second. We evaluated pressure, stress, and strain distributions in gold and a mixture of gold and iron as well as in secondary anvils using synchrotron x-ray diffraction with a micro-focused beam. A maximum pressure of 240 GPa was reached independent of the first stage anvil culet size. We found that the stress field generated by the second stage anvils is typical of conventional DAC experiments. The maximum pressures reached are limited by strains developing in the secondary anvil and by cupping of the first stage diamond anvil in the presented experimental designs. Also, our experiments show that pressures of several megabars may be reached without sacrificing the first stage diamond anvils.

  3. Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

    SciTech Connect (OSTI)

    Rainer Wallny

    2012-10-15

    Diamond was studied as a possible radiation hard technology for use in future high radiation environments. With the commissioning of the LHC expected in 2010, and the LHC upgrades expected in 2015, all LHC experiments are planning for detector upgrades which require radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is installed and operational in all LHC experiments. As a result, this material is now being discussed as an alternative sensor material for tracking very close to the interaction region of the super-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications.

  4. Metal/Diamond Composite Thin-Film Electrodes: New Carbon Supported Catalytic Electrodes

    SciTech Connect (OSTI)

    Greg M. Swain, PI

    2009-03-10

    The DOE-funded research conducted by the Swain group was focused on (i) understanding structure-function relationships at boron-doped diamond thin-film electrodes, (ii) understanding metal phase formation on diamond thin films and developing electrochemical approaches for producing highly dispersed electrocatalyst particles (e.g., Pt) of small nominal particle size, (iii) studying the electrochemical activity of the electrocatalytic electrodes for hydrogen oxidation and oxygen reduction and (iv) conducting the initial synthesis of high surface area diamond powders and evaluating their electrical and electrochemical properties when mixed with a Teflon binder. (Note: All potentials are reported versus Ag/AgCl (sat'd KCl) and cm{sup 2} refers to the electrode geometric area, unless otherwise stated).

  5. Ultraviolet photosensitivity of sulfur-doped micro- and nano-crystalline diamond

    SciTech Connect (OSTI)

    Mendoza, Frank; Makarov, Vladimir; Hidalgo, Arturo; Weiner, Brad; Morell, Gerardo

    2011-06-06

    The room-temperature photosensitivity of sulfur-doped micro- (MCD), submicro- (SMCD) and nano- (NCD) crystalline diamond films synthesized by hot-filament chemical vapor deposition was studied. The structure and composition of these diamond materials were characterized by Raman spectroscopy, scanning electron microscopy and X-ray diffraction. The UV sensitivity and response time were studied for the three types of diamond materials using a steady state broad UV excitation source and two pulsed UV laser radiations. It was found that they have high sensitivity in the UV region, as high as 109 sec-1mV-1 range, linear response in a broad spectral range below 320 nm, photocurrents around ~10-5 A, and short response time better than 100 ns, which is independent of fluency intensity. A phenomenological model was applied to help understand the role of defects and dopant concentration on the materials’ photosensitivity.

  6. In situ laser heating and radial synchrotron x-ray diffraction in a diamond anvil cell

    SciTech Connect (OSTI)

    Kunz, Martin; Caldwell, Wendel A.; Miyagi, Lowell; Wenk, Hans-Rudolf

    2007-06-15

    We report a first combination of diamond anvil cell radial x-ray diffraction with in situ laser heating. The laser-heating setup of ALS beamline 12.2.2 was modified to allow one-sided heating of a sample in a diamond anvil cell with an 80 W yttrium lithium fluoride laser while probing the sample with radial x-ray diffraction. The diamond anvil cell is placed with its compressional axis vertical, and perpendicular to the beam. The laser beam is focused onto the sample from the top while the sample is probed with hard x-rays through an x-ray transparent boron-epoxy gasket. The temperature response of preferred orientation of (Fe,Mg)O is probed as a test experiment. Recrystallization was observed above 1500 K, accompanied by a decrease in stress.

  7. In situ laser heating and radial synchrotron X-ray diffraction ina diamond anvil cell

    SciTech Connect (OSTI)

    Kunz, Martin; Caldwell, Wendel A.; Miyagi, Lowell; Wenk,Hans-Rudolf

    2007-06-29

    We report a first combination of diamond anvil cell radialx-ray diffraction with in situ laser heating. The laser-heating setup ofALS beamline 12.2.2 was modified to allow one-sided heating of a samplein a diamond anvil cell with an 80 W yttrium lithium fluoride laser whileprobing the sample with radial x-ray diffraction. The diamond anvil cellis placed with its compressional axis vertical, and perpendicular to thebeam. The laser beam is focused onto the sample from the top while thesample is probed with hard x-rays through an x-ray transparentboron-epoxy gasket. The temperature response of preferred orientation of(Fe,Mg)O is probed as a test experiment. Recrystallization was observedabove 1500 K, accompanied by a decrease in stress.

  8. Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

    SciTech Connect (OSTI)

    Harris Kagan; K.K. Gan; Richard Kass

    2009-03-31

    Diamond was studied as a possible radiation hard technology for use in future high radiation environments. With the commissioning of the LHC expected in 2009, and the LHC upgrades expected in 2013, all LHC experiments are planning for detector upgrades which require radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is installed in all LHC experiments. As a result, this material is now being discussed as an alternative sensor material for tracking very close to the interaction region of the super-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications.

  9. Ultraviolet photosensitivity of sulfur-doped micro- and nano-crystalline diamond

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

    Mendoza, Frank; Makarov, Vladimir; Hidalgo, Arturo; Weiner, Brad; Morell, Gerardo

    2011-06-06

    The room-temperature photosensitivity of sulfur-doped micro- (MCD), submicro- (SMCD) and nano- (NCD) crystalline diamond films synthesized by hot-filament chemical vapor deposition was studied. The structure and composition of these diamond materials were characterized by Raman spectroscopy, scanning electron microscopy and X-ray diffraction. The UV sensitivity and response time were studied for the three types of diamond materials using a steady state broad UV excitation source and two pulsed UV laser radiations. It was found that they have high sensitivity in the UV region, as high as 109 sec-1mV-1 range, linear response in a broad spectral range below 320 nm, photocurrentsmore » around ~10-5 A, and short response time better than 100 ns, which is independent of fluency intensity. A phenomenological model was applied to help understand the role of defects and dopant concentration on the materials’ photosensitivity.« less

  10. Large area polycrystalline diamond films as high current photocathodes for linear induction accelerators

    SciTech Connect (OSTI)

    Shurter, R.P.; Moir, D.C.; Devlin, D.J.; Springer, R.W.

    1997-08-01

    Investigations are underway at Los Alamos to develop a new generation of high current, low source temperature photo cathodes able to operate in vacuum environments with pressures above 10e-6 torr without poisoning or degradation of emission properties. Polycrystalline diamond films are emerging as the ideal material for these photocathodes. Robustness, high quantum efficiency and high thermal conductivity are fundamental necessary attributes that are found in diamond. The high electron/hole mobility in the boron doped diamond lattice and the ability to create a negative electron affinity surface through downward band bending allow for high current density emission with quantum efficiencies of 0.5% when illuminated by a ArF laser. We report the results to date toward the development of a four kiloampere photocathode with a source temperature below 5eV for the DARHT linear induction Accelerator

  11. Development of Designer Diamond Technology for High Pressure High Temperature Experiments in Support of Stockpile Stewardship Program

    SciTech Connect (OSTI)

    Vohra, Yogesh, K.

    2009-10-28

    The role of nitrogen in the fabrication of designer diamond was systematically investigated by adding controlled amount of nitrogen in hydrogen/methane/oxygen plasma. This has led to a successful recipe for reproducible fabrication of designer diamond anvils for high-pressure high-temperature research in support of stockpile stewardship program. In the three-year support period, several designer diamonds fabricated with this new growth chemistry were utilized in high-pressure experiments at UAB and Lawrence Livermore National Laboratory. The designer diamond anvils were utilized in high-pressure studies on heavy rare earth metals, high pressure melting studies on metals, and electrical resistance measurements on iron-based layered superconductors under high pressures. The growth chemistry developed under NNSA support can be adapted for commercial production of designer diamonds.

  12. The Development of Open Water-lubricated Polycrystalline Diamond (PCD) Thrust Bearings for Use in Marine Hydrokinetic (MHK) Energy Machines

    SciTech Connect (OSTI)

    Cooley, Craig, H.; Khonsari, Michael,, M; Lingwall, Brent

    2012-11-28

    Polycrstalline diamond (PCD) bearings were designed, fabricated and tested for marine-hydro-kinetic (MHK) application. Bearing efficiency and life were evaluated using the US Synthetic bearing test facility. Three iterations of design, build and test were conducted to arrive at the best bearing design. In addition life testing that simulated the starting and stopping and the loading of real MHK applications were performed. Results showed polycrystalline diamond bearings are well suited for MHK applications and that diamond bearing technology is TRL4 ready. Based on life tests results bearing life is estimated to be at least 11.5 years. A calculation method for evaluating the performance of diamond bearings of round geometry was also investigated and developed. Finally, as part of this effort test bearings were supplied free of charge to the University of Alaska for further evaluation. The University of Alaska test program will subject the diamond bearings to sediment laden lubricating fluid.

  13. The Nanoscience Beamline at Diamond, Optical Design Considerations

    SciTech Connect (OSTI)

    Reininger, Ruben; Dhesi, Sarnjeet

    2007-01-19

    The main requirement of the Nanoscience Beamline at Diamond is to deliver the highest possible flux at the sample position of a PEEM with a resolving power of about 5000 in the energy range 80-2000 eV. The source of the beamline is a couple of APPLE II helical undulators in tandem that can also be used separately to allow for faster switching of the circular polarization. Based on its versatility, a collimated plane grating monochromator using sagittally focusing elements was chosen to cover the required energy range with three gratings. The operation of this monochromator requires a collimated beam incident on the grating along the dispersion direction. This can be achieved either with a toroid, focusing with its major radius along the non-dispersive direction at the exit slit, or with a sagittal cylinder. The former option uses a sagittal cylinder after the grating to focus the collimated beam at the exit slit. In the latter case, a toroid after the grating is used to focus in both directions at the exit slit. The advantage of the toroid downstream the grating is the higher horizontal demagnification. This configuration fulfills the Nanoscience Beamline's required resolving power but cannot be used to achieve very high resolution due to the astigmatic coma aberration of the toroidal mirror. The focusing at the sample position is performed with a KB pair of plane elliptical mirrors. Assuming achievable values for the errors on all the optical surfaces, the expected spots FWHW in the horizontal and vertical directions are 10 {mu}m and 3 {mu}m, respectively. The calculated photon flux at this spot at 5000 resolving power is >1012 photons/sec between 80 and 1600 eV for linearly polarized light and between 106 and 1200 eV for circularly polarized light. The beamline is expected to be operational in January 2007.

  14. Science and technology of ultrananocrystalline diamond (UNCD) thin films for multifunctional devices.

    SciTech Connect (OSTI)

    Auciello, O.; Gruen, D. M.; Krauss, A. R.; Jayatissa, A.; Sumant, A.; Tucek, J.; Mancini, D.; Moldovan, N.; Erdemir, A.; Ersoy, D.; Gardos, M. N.; Busmann, H. G.; Meyer, E. M.

    2000-11-15

    MEMS devices are currently fabricated primarily in silicon because of the available surface machining technology. However, Si has poor mechanical and tribological properties, and practical MEMS devices are currently limited primarily to applications involving only bending and flexural motion, such as cantilever accelerometers and vibration sensors, However, because of the poor flexural strength and fracture toughness of Si, and the tendency of Si to adhere to hydrophyllic surfaces, even these simple devices have limited dynamic range. Future MEMS applications that involve significant rolling or sliding contact will require the use of new materials with significantly improved mechanical and tribological properties, and the ability to perform well in harsh environments. Diamond is a superhard material of high mechanical strength, exceptional chemical inertness, and outstanding thermal stability. The brittle fracture strength is 23 times that of Si, and the projected wear life of diamond MEMS moving mechanical assemblies (MEMS-MMAS) is 10,000 times greater than that of Si MMAs. However, as the hardest known material, diamond is notoriously difficult to fabricate. Conventional CVD thin film deposition methods offer an approach to the fabrication of ultra-small diamond structures, but the films have large grain size, high internal stress, poor intergranular adhesion, and very rough surfaces, and are consequently ill-suited for MEMS-MMA applications. A thin film deposition process has been developed that produces phase-pure ultrananocrystalline diamond (UNCD) with morphological and mechanical properties that are ideally suited for MEMS applications in general, and MMA use in particular. We have developed lithographic techniques for the fabrication of diamond microstructure including cantilevers and multi-level devices, acting as precursors to micro-bearings and gears, making UNCD a promising material for the development of high performance MEMS devices.

  15. Field emission from bias-grown diamond thin films in a microwave plasma

    DOE Patents [OSTI]

    Gruen, Dieter M.; Krauss, Alan R.; Ding, Ming Q.; Auciello, Orlando

    2002-01-01

    A method of producing diamond or diamond like films in which a negative bias is established on a substrate with an electrically conductive surface in a microwave plasma chemical vapor deposition system. The atmosphere that is subjected to microwave energy includes a source of carbon, nitrogen and hydrogen. The negative bias is maintained on the substrate through both the nucleation and growth phase of the film until the film is continuous. Biases between -100V and -200 are preferred. Carbon sources may be one or more of CH.sub.4, C.sub.2 H.sub.2 other hydrocarbons and fullerenes.

  16. Photo-stimulated low electron temperature high current diamond film field emission cathode

    DOE Patents [OSTI]

    Shurter; Roger Philips , Devlin; David James , Moody; Nathan Andrew , Taccetti; Jose Martin , Russell; Steven John

    2012-07-24

    An electron source includes a back contact surface having a means for attaching a power source to the back contact surface. The electron source also includes a layer comprising platinum in direct contact with the back contact surface, a composite layer of single-walled carbon nanotubes embedded in platinum in direct contact with the layer comprising platinum. The electron source also includes a nanocrystalline diamond layer in direct contact with the composite layer. The nanocrystalline diamond layer is doped with boron. A portion of the back contact surface is removed to reveal the underlying platinum. The electron source is contained in an evacuable container.

  17. Synthesis of new Diamond-like B-C Phases under High Pressure and Temperatures

    SciTech Connect (OSTI)

    Ming, L. C.; Zinin, P. V.; Sharma, S. K.

    2014-04-22

    A cubic BC3 (c-BC3) phase was synthesized by direct transformation from graphitic phases at a pressure of 39 GPa and temperature of 2200 K in a laser-heated diamond anvil cell (DAC). A combination of x-ray diffraction (XRD), electron diffraction (ED), transmission electron microscopy (TEM) imaging, and electron energy loss spectroscopy (EELS) measurements lead us to conclude that the obtained phase is hetero-nano-diamond, c-BC3. The EELS measurements show that the atoms inside the cubic structure are bonded by sp3 bonds.

  18. N-type droping of nanocrystalline diamond films with nitrogen and electrodes made therefrom

    DOE Patents [OSTI]

    Gruen, Dieter M.; Krauss, Alan R.; Auciello, Orlando H.; Carlisle, John A.

    2004-09-21

    An electrically conducting n-type ultrananocrystalline diamond (UNCD) having no less than 10.sup.19 atoms/cm.sup.3 of nitrogen is disclosed. A method of making the n-doped UNCD. A method for predictably controlling the conductivity is also disclosed.

  19. Optical emission diagnostics of plasmas in chemical vapor deposition of single-crystal diamond

    SciTech Connect (OSTI)

    Hemawan, Kadek W. Hemley, Russell J.

    2015-11-15

    A key aspect of single crystal diamond growth via microwave plasma chemical vapor deposition is in-process control of the local plasma–substrate environment, that is, plasma gas phase concentrations of activated species at the plasma boundary layer near the substrate surface. Emission spectra of the plasma relative to the diamond substrate inside the microwave plasma reactor chamber have been analyzed via optical emission spectroscopy. The spectra of radical species such as CH, C{sub 2}, and H (Balmer series) important for diamond growth were identified and analyzed. The emission intensities of these electronically excited species were found to be more dependent on operating pressure than on microwave power. Plasma gas temperatures were calculated from measurements of the C{sub 2} Swan band (d{sup 3}Π → a{sup 3}Π transition) system. The plasma gas temperature ranges from 2800 to 3400 K depending on the spatial location of the plasma ball, microwave power and operating pressure. Addition of Ar into CH{sub 4}+H{sub 2} plasma input gas mixture has little influence on the Hα, Hβ, and Hγ intensities and single-crystal diamond growth rates.

  20. Online remote control systems for static and dynamic compression and decompression using diamond anvil cells

    SciTech Connect (OSTI)

    Sinogeikin, Stanislav V. Smith, Jesse S.; Rod, Eric; Lin, Chuanlong; Kenney-Benson, Curtis; Shen, Guoyin

    2015-07-15

    The ability to remotely control pressure in diamond anvil cells (DACs) in accurate and consistent manner at room temperature, as well as at cryogenic and elevated temperatures, is crucial for effective and reliable operation of a high-pressure synchrotron facility such as High Pressure Collaborative Access Team (HPCAT). Over the last several years, a considerable effort has been made to develop instrumentation for remote and automated pressure control in DACs during synchrotron experiments. We have designed and implemented an array of modular pneumatic (double-diaphragm), mechanical (gearboxes), and piezoelectric devices and their combinations for controlling pressure and compression/decompression rate at various temperature conditions from 4 K in cryostats to several thousand Kelvin in laser-heated DACs. Because HPCAT is a user facility and diamond cells for user experiments are typically provided by users, our development effort has been focused on creating different loading mechanisms and frames for a variety of existing and commonly used diamond cells rather than designing specialized or dedicated diamond cells with various drives. In this paper, we review the available instrumentation for remote static and dynamic pressure control in DACs and show some examples of their applications to high pressure research.

  1. Diamond anvil cell for spectroscopic investigation of materials at high temperature, high pressure and shear

    DOE Patents [OSTI]

    Westerfield, C.L.; Morris, J.S.; Agnew, S.F.

    1997-01-14

    Diamond anvil cell is described for spectroscopic investigation of materials at high temperature, high pressure and shear. A cell is described which, in combination with Fourier transform IR spectroscopy, permits the spectroscopic investigation of boundary layers under conditions of high temperature, high pressure and shear. 4 figs.

  2. Diamond anvil cell for spectroscopic investigation of materials at high temperature, high pressure and shear

    DOE Patents [OSTI]

    Westerfield, Curtis L.; Morris, John S.; Agnew, Stephen F.

    1997-01-01

    Diamond anvil cell for spectroscopic investigation of materials at high temperature, high pressure and shear. A cell is described which, in combination with Fourier transform IR spectroscopy, permits the spectroscopic investigation of boundary layers under conditions of high temperature, high pressure and shear.

  3. Large improvement of phosphorus incorporation efficiency in n-type chemical vapor deposition of diamond

    SciTech Connect (OSTI)

    Ohtani, Ryota; Yamamoto, Takashi; Janssens, Stoffel D.; Yamasaki, Satoshi

    2014-12-08

    Microwave plasma enhanced chemical vapor deposition is a promising way to generate n-type, e.g., phosphorus-doped, diamond layers for the fabrication of electronic components, which can operate at extreme conditions. However, a deeper understanding of the doping process is lacking and low phosphorus incorporation efficiencies are generally observed. In this work, it is shown that systematically changing the internal design of a non-commercial chemical vapor deposition chamber, used to grow diamond layers, leads to a large increase of the phosphorus doping efficiency in diamond, produced in this device, without compromising its electronic properties. Compared to the initial reactor design, the doping efficiency is about 100 times higher, reaching 10%, and for a very broad doping range, the doping efficiency remains highly constant. It is hypothesized that redesigning the deposition chamber generates a higher flow of active phosphorus species towards the substrate, thereby increasing phosphorus incorporation in diamond and reducing deposition of phosphorus species at reactor walls, which additionally reduces undesirable memory effects.

  4. High quality factor nanocrystalline diamond micromechanical resonators limited by thermoelastic damping

    SciTech Connect (OSTI)

    Najar, Hadi; Chan, Mei-Lin; Yang, Hsueh-An; Lin, Liwei; Cahill, David G.; Horsley, David A.

    2014-04-14

    We demonstrate high quality factor thin-film nanocrystalline diamond micromechanical resonators with quality factors limited by thermoelastic damping. Cantilevers, single-anchored and double-anchored double-ended tuning forks, were fabricated from 2.5??m thick in-situ boron doped nanocrystalline diamond films deposited using hot filament chemical vapor deposition. Thermal conductivity measured by time-domain thermoreflectance resulted in 24?±?3?W m{sup ?1} K{sup ?1} for heat transport through the thickness of the diamond film. The resonant frequencies of the fabricated resonators were 46?kHz–8?MHz and showed a maximum measured Q???86?000 at f{sub n}?=?46.849?kHz. The measured Q-factors are shown to be in good agreement with the limit imposed by thermoelastic dissipation calculated using the measured thermal conductivity. The mechanical properties extracted from resonant frequency measurements indicate a Young's elastic modulus of ?788?GPa, close to that of microcrystalline diamond.

  5. Characterization of diamond film and bare metal photocathodes as a function of temperature and surface preparation

    SciTech Connect (OSTI)

    Shurter, R.P.; Moir, D.C.; Devlin, D.J.

    1996-07-01

    High current photocathodes using bare metal and polycrystalline diamond films illuminated by ultraviolet lasers are being developed at Los Alamos for use in a new generation of linear induction accelerators. These photocathodes must be able to produce multiple 60 ns pulses separated by several to tens of nanoseconds. The vacuum environment in which the photocathodes must operate is 10{sup -5} torr.

  6. Propagation and absorption of high-intensity femtosecond laser radiation in diamond

    SciTech Connect (OSTI)

    Kononenko, V V; Konov, V I; Gololobov, V M; Zavedeev, E V

    2014-12-31

    Femtosecond interferometry has been used to experimentally study the photoexcitation of the electron subsystem of diamond exposed to femtosecond laser pulses of intensity 10{sup 11} to 10{sup 14} W cm{sup -2}. The carrier concentration has been determined as a function of incident intensity for three harmonics of a Ti : sapphire laser (800, 400 and 266 nm). The results demonstrate that, in a wide range of laser fluences (up to those resulting in surface and bulk graphitisation), a well-defined multiphoton absorption prevails. We have estimated nonlinear absorption coefficients for pulsed radiation at λ = 800 nm (four-photon transition) and at 400 and 266 nm (indirect and direct two-photon transitions, respectively). It has also been shown that, at any considerable path length of a femtosecond pulse in diamond (tens of microns or longer), the laser beam experiences a severe nonlinear transformation, determining the amount of energy absorbed by the lattice, which is important for the development of technology for diamond photostructuring by ultrashort pulses. The competition between wave packet self-focusing and the plasma defocusing effect is examined as a major mechanism governing the propagation of intense laser pulses in diamond. (interaction of laser radiation with matter. laser plasma)

  7. Ultratough, Thermally Stable Polycrystalline Diamond/Silicon Carbide Nanocomposites for Drill Bits

    SciTech Connect (OSTI)

    2009-03-01

    This factsheet describes a research project whose goal is to develop and produce in quantity novel superhard and ultratough thermally stable polycrystalline (TSP) diamond/SiC nanocomposites reinforced with SiC/C nanofibers for drill-bit applications and multiple industrial functions.

  8. Method to grow pure nanocrystalline diamond films at low temperatures and high deposition rates

    DOE Patents [OSTI]

    Carlisle, John A.; Gruen, Dieter M.; Auciello, Orlando; Xiao, Xingcheng

    2009-07-07

    A method of depositing nanocrystalline diamond film on a substrate at a rate of not less than about 0.2 microns/hour at a substrate temperature less than about 500.degree. C. The method includes seeding the substrate surface with nanocrystalline diamond powder to an areal density of not less than about 10.sup.10sites/cm.sup.2, and contacting the seeded substrate surface with a gas of about 99% by volume of an inert gas other than helium and about 1% by volume of methane or hydrogen and one or more of acetylene, fullerene and anthracene in the presence of a microwave induced plasma while maintaining the substrate temperature less than about 500.degree. C. to deposit nanocrystalline diamond on the seeded substrate surface at a rate not less than about 0.2 microns/hour. Coatings of nanocrystalline diamond with average particle diameters of less than about 20 nanometers can be deposited with thermal budgets of 500.degree. C.-4 hours or less onto a variety of substrates such as MEMS devices.

  9. Fabrication and characterization of a co-planar detector in diamond for low energy single ion implantation

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

    Abraham, John Bishoy Sam; Pacheco, Jose L.; Aguirre, Brandon Adrian; Vizkelethy, Gyorgy; Bielejec, Edward S.

    2016-05-01

    We demonstrate low energy single ion detection using a co-planar detector fabricated on a diamond substrate and characterized by ion beam induced charge collection. Histograms are taken with low fluence ion pulses illustrating quantized ion detection down to a single ion with a signal-to-noise ratio of approximately 10. We anticipate that this detection technique can serve as a basis to optimize the yield of single color centers in diamond. In conclusion, the ability to count ions into a diamond substrate is expected to reduce the uncertainty in the yield of color center formation by removing Poisson statistics from the implantationmore » process.« less

  10. Fabrication of large radii toroidal surfaces by single point diamond turning

    SciTech Connect (OSTI)

    Cunningham, J.P.; Marlar, T.A.; Miller, A.C.; Paterson, R. L.

    1995-12-31

    An unconventional machining technique has been developed for producing relatively large radii quasi-toroidal surfaces which could not normally be produced by conventional diamond turning technology. The maximum radial swing capacity of a diamond turning lathe is the limiting factor for the rotational radius of any toroid. A typical diamond turned toroidal surface is produced when a part is rotated about the spindle axis while the diamond tool contours the surface with any curved path. Toric surfaces sliced horizontally, have been used in laser resonator cavities. This paper will address the fabrication of a special case of toroids where a rotating tool path is a circle whose center is offset from the rotational axis of the toroid by a distance greater than the minor radius of the tool path. The quasi-toroidal surfaces produced by this technique approximate all asymmetrical combinations of concave/convex section of a torus. Other machine configurations have been reported which offer alternative approaches to the fabrication of concave asymmetric aspheric surfaces. Prototypes of unique lenses each having two quasi-toroidal surfaces were fabricated in the Ultraprecision Manufacturing Technology Center at form key components of a scanned laser focusing system. As an example of the problem faced, the specifications for one of the surfaces was equivalent to a section of a torus with a two meter diameter hole. The lenses were fabricated on a Nanoform 600 diamond turning lathe. This is a numerically controlled two axis T-base lathe with an air bearing spindle and oil hydrostatic slides. The maximum radial swing for this machine is approximately 0.3 meters.