National Library of Energy BETA

Sample records for lead-free solder misbehaves

  1. Lead-free solder

    DOE Patents [OSTI]

    Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA)

    2001-05-15

    A Sn--Ag--Cu eutectic alloy is modified with one or more low level and low cost alloy additions to enhance high temperature microstructural stability and thermal-mechanical fatigue strength without decreasing solderability. Purposeful fourth or fifth element additions in the collective amount not exceeding about 1 weight % (wt. %) are added to Sn--Ag--Cu eutectic solder alloy based on the ternary eutectic Sn--4.7%Ag--1.7%Cu (wt. %) and are selected from the group consisting essentially of Ni, Fe, and like-acting elements as modifiers of the intermetallic interface between the solder and substrate to improve high temperature solder joint microstructural stability and solder joint thermal-mechanical fatigue strength.

  2. Breakthrough: Lead-free Solder

    SciTech Connect (OSTI)

    Anderson, Iver

    2012-01-01

    Ames Laboratory senior metallurgist Iver Anderson explains the importance of lead-free solder in taking hazardous lead out of the environment by eliminating it from discarded computers and electronics that wind up in landfills. Anderson led a team that developed a tin-silver-copper replacement for traditional lead-tin solder that has been adopted by more than 50 companies worldwide.

  3. Breakthrough: Lead-free Solder

    ScienceCinema (OSTI)

    Anderson, Iver

    2013-03-01

    Ames Laboratory senior metallurgist Iver Anderson explains the importance of lead-free solder in taking hazardous lead out of the environment by eliminating it from discarded computers and electronics that wind up in landfills. Anderson led a team that developed a tin-silver-copper replacement for traditional lead-tin solder that has been adopted by more than 50 companies worldwide.

  4. Microstructure and In Situ Observations of Undercooling for Nucleation of ?-Sn Relevant to Lead-Free Solder Alloys

    E-Print Network [OSTI]

    Elmer, John W.; Specht, Eliot D.; Kumar, Mukul

    2010-01-01

    K.J. Puttlitz, Handbook of Lead-Free Solder Technology forNucleation of b-Sn Relevant to Lead-Free Solder Alloys JOHNcation of tin and tin-based lead-free solder alloys can

  5. Lead-Free Solder Paste | The Ames Laboratory

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

    hazard, that's not its only advantage," says Ames Lab's Iver Anderson, co-inventor of a new solder from tin, silver and copper. "We worked with different alloy...

  6. 1-4244-0665-X/06/$20.00 2006 IEEE 781 2006 Electronics Packaging Technology Conference Development of Life Prediction Model for Lead-free Solder at Chip Resistor

    E-Print Network [OSTI]

    Berlin,Technische Universität

    of Life Prediction Model for Lead-free Solder at Chip Resistor Changwoon Han and Byeongsuk Song-mail : cw_han@keti.re.kr Abstract An accelerated thermal cycling test to assess the reliability of lead-free solders at chip resistor has been conducted. Test results indicate that the life of lead-free solder

  7. Accepted for publication Microelectronics Reliability February 1, 2014 Assessing the value of a lead-free solder control plan using cost-

    E-Print Network [OSTI]

    Sandborn, Peter

    of a lead-free solder control plan using cost- based FMEA Edwin Lilliea , Peter Sandborna , David Humphreyb choose or be required to perform to ensure product performance. This paper uses cost-based FMEA

  8. Tuning and parameter optimization of a digital integral controller for uniform droplet spray applications using lead-free tin-copper solder

    E-Print Network [OSTI]

    De Castro, Eloisa M

    2009-01-01

    The advent of legislation restricting the use of lead in electronics requires innovation and refinement in processes for creating lead-free solder spheres for wafer bumping and other surface mount technology. Operation ...

  9. Suppressing tin whisker growth in lead-free solders and platings

    DOE Patents [OSTI]

    Hoffman, Elizabeth N; Lam, Poh-Sang

    2014-04-29

    A process of irradiation Sn containing Pb-free solder to mitigate whisker formation and growth thereon is provided. The use of gamma radiation such as cobalt-60 has been applied to a substrate of Sn on copper has been found to change the morphology of the crystalline whisker growth to a more truncated hillock pattern. The change in morphology greatly reduces the tendency of whiskers to contribute to electrical short-circuits being used as a Pb-free solder system on a copper substrate.

  10. Microstructure and Sn crystal orientation evolution in Sn-3.5Ag lead-free solders in high temperature packaging applications

    SciTech Connect (OSTI)

    Zhou, Bite [ORNL; Muralidharan, Govindarajan [ORNL; Kurumaddali, Nalini Kanth [ORNL; Parish, Chad M [ORNL; Leslie, Dr Scott [Powerex Inc; Bieler, T. R. [Michigan State University, East Lansing

    2014-01-01

    Understanding the reliability of eutectic Sn-3.5Ag lead-free solders in high temperature packaging applications is of significant interest in power electronics for the next generation electric grid. Large area (2.5mm 2.5mm) Sn-3.5Ag solder joints between silicon dies and direct bonded copper substrates were thermally cycled between 5 C and 200 C. Sn crystal orientation and microstructure evolution during thermal cycling were characterized by electron backscatter diffraction (EBSD) in scanning electron microscope (SEM). Comparisons are made between observed initial texture and microstructure and its evolution during thermal cycling. Gradual lattice rotation and grain boundary misorientation evolution suggested the continuous recrystallization mechanism. Recrystallization behavior was correlated with dislocation slip activities.

  11. Wave soldering with Pb-free solders

    SciTech Connect (OSTI)

    Artaki, I.; Finley, D.W.; Jackson, A.M.; Ray, U.; Vianco, P.T.

    1995-07-01

    The manufacturing feasibility and attachment reliability of a series of newly developed lead-free solders were investigated for wave soldering applications. Some of the key assembly aspects addressed included: wettability as a function of board surface finish, flux activation and surface tension of the molten solder, solder joint fillet quality and optimization of soldering thermal profiles. Generally, all new solder formulations exhibited adequate wave soldering performance and can be considered as possible alternatives to eutectic SnPb for wave soldering applications. Further process optimization and flux development is necessary to achieve the defect levels associated with the conventional SnPb process.

  12. Lead-free primary explosives

    DOE Patents [OSTI]

    Huynh, My Hang V.

    2010-06-22

    Lead-free primary explosives of the formula (cat).sub.Y[M.sup.II(T).sub.X(H.sub.2O).sub.6-X].sub.Z, where T is 5-nitrotetrazolate, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  13. Reactive Spreading of a Lead-Free Solder on Alumina

    E-Print Network [OSTI]

    Gremillard, L.; Saiz, E.; Radmilovic, V.R.; Tomsia, A.P.

    2008-01-01

    below 550°C, a solid oxide layer encapsulates the liquidoxidation of tin, a tin oxide layer around the metallic dropto the formation of an oxide layer encapsulating the metal.

  14. Lab Breakthrough: Lead-free Solder | Department of Energy

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

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

  15. Advances in Fine Pitch Lead Free Assembly Process Ravi Doraiswami, Sandeep Sankararaman,Woopoung Kim, Jmg Li, Zhuqing Zhang, Piyush Gupta, Kensuke Nakanishi',

    E-Print Network [OSTI]

    Swaminathan, Madhavan

    by which solder can be deposited on the UBM without stencil printing or electroplating. Flip chip B. Conventional humping techniques like screen printing and electroplating have their inherent limitations paste are the limitations for bumping through screen printing [5]. Electroplating ternaty lead free

  16. Lead-Free Surface Finishes for Electronic Components

    E-Print Network [OSTI]

    Lead-Free Surface Finishes for Electronic Components: Tin Whisker Growth METALS This project degraded by the switch to lead- free technology. In particular, the state of compressive stress and the localized creep response (whisker growth) of tin-based lead-free electrodeposits are being measured

  17. Suppression of Tin Whiskers in Lead-Free Solder - Energy Innovation Portal

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With Livermore National LabSupplier

  18. Investigation of Gold Nanoparticle Inks for Low-Temperature Lead-Free Packaging Technology

    E-Print Network [OSTI]

    Bakhishev, Teymur; Subramanian, Vivek

    2009-01-01

    Symposium on Advanced Packaging Materials: Processes,Temperature Lead-Free Packaging Technology TEYMUR BAKHISHEVcandidate for lead-free packaging applications. Inks

  19. 978-1-4244-7265-9/10/$26.00 c2010 IEEE Misbehaving Router Detection in Link-state

    E-Print Network [OSTI]

    Levente, Buttyįn

    }@crysys.hu Abstract In this paper, we address the problem of detecting misbehaving routers in wireless mesh networks consists of mesh routers that form a static wireless ad hoc network. Some of the mesh routers function978-1-4244-7265-9/10/$26.00 c2010 IEEE Misbehaving Router Detection in Link-state Routing

  20. KNN–NTK composite lead-free piezoelectric ceramic

    SciTech Connect (OSTI)

    Matsuoka, T. Kozuka, H.; Kitamura, K.; Yamada, H.; Kurahashi, T.; Yamazaki, M.; Ohbayashi, K.

    2014-10-21

    A (K,Na)NbO?-based lead-free piezoelectric ceramic was successfully densified. It exhibited an enhanced electromechanical coupling factor of k?=0.52, a piezoelectric constant d??=252 pC/N, and a frequency constant N?=3170 Hz m because of the incorporation of an elaborate secondary phase composed primarily of KTiNbO?. The ceramic's nominal composition was 0.92K?.??Na?.??Ca?.??Li?.??Nb?.??O?–0.047K?.??Ti?.??Nb?.??O?–0.023BaZrO? –0.0017Co?O?–0.002Fe?O?–0.005ZnO, abbreviated herein as KNN–NTK composite. The KNN–NTK ceramic exhibited a dense microstructure with few microvoids which significantly degraded its piezoelectric properties. Elemental maps recorded using transmission electron microscopy with energy-dispersive X-ray spectroscopy (TEM–EDS) revealed regions of high concentrations of Co and Zn inside the NTK phase. In addition, X-ray diffraction patterns confirmed that a small portion of the NTK phase was converted into K?(Ti,Nb,Co,Zn)?O?? or CoZnTiO? by a possible reaction between Co and Zn solutes and the NTK phase during a programmed sintering schedule. TEM studies also clarified a distortion around the KNN/NTK interfaces. Such an NTK phase filled voids between KNN particles, resulting in an improved chemical stability of the KNN ceramic. The manufacturing process was subsequently scaled to 100 kg per batch for granulated ceramic powder using a spray-drying technique. The properties of the KNN–NTK composite ceramic produced using the scaled-up method were confirmed to be identical to those of the ceramic prepared by conventional solid-state reaction sintering. Consequently, slight changes in the NTK phase composition and the distortion around the KNN/NTK interfaces affected the KNN–NTK composite ceramic's piezoelectric characteristics.

  1. 978-1-4244-7265-9/10/$26.00 c2010 IEEE Misbehaving Router Detection in Link-state Routing for Wireless Mesh Networks

    E-Print Network [OSTI]

    Bencsįth, Boldizsįr

    }@crysys.hu Abstract--In this paper, we address the problem of detecting misbehaving routers in wireless mesh networks consists of mesh routers that form a static wireless ad hoc network. Some of the mesh routers function978-1-4244-7265-9/10/$26.00 c2010 IEEE Misbehaving Router Detection in Link-state Routing

  2. Preparation and Characterization of Lead-free Piezoelectric Ceramics Qiang Chen1,a

    E-Print Network [OSTI]

    Volinsky, Alex A.

    Preparation and Characterization of Lead-free Piezoelectric Ceramics Qiang Chen1,a , Jinxu Li1,b properties; Perovskites; (K,Na)NbO3 Abstract. (K,Na)NbO3-based piezoelectric ceramics are promising piezoelectric properties. In this paper, lead-free piezoelectric ceramics (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0

  3. Tin-silver-bismuth solders for electronics assembly

    DOE Patents [OSTI]

    Vianco, P.T.; Rejent, J.A.

    1995-08-08

    A lead-free solder alloy is disclosed for electronic assemblies composed of a eutectic alloy of tin and silver with a bismuth addition, x, of 0

  4. Tin-silver-bismuth solders for electronics assembly

    DOE Patents [OSTI]

    Vianco, Paul T. (Albuquerque, NM); Rejent, Jerome A. (Albuquerque, NM)

    1995-01-01

    A lead-free solder alloy for electronic assemblies composed of a eutectic alloy of tin and silver with a bismuth addition, x, of 0

  5. Solder self-assembly for MEMS fabrication

    E-Print Network [OSTI]

    Au, Hin Meng, 1977-

    2004-01-01

    This thesis examines and demonstrates self-assembly of MEMS components on the 25 micron scale onto substrates using the capillary force of solder. This is an order of magnitude smaller than current solder self-assembly in ...

  6. Lead-free precussion primer mixes based on metastable interstitial composite (MIC) technology

    DOE Patents [OSTI]

    Dixon, George P. (Alexandria, VA); Martin, Joe A. (Espanola, NM); Thompson, Don (Ridgecrest, CA)

    1998-01-01

    A lead-free percussion primer composition and a percussion cup containing e composition. The lead-free percussion primer composition is comprised of a mixture of about 45 wt % aluminum powder having an outer coating of aluminum oxide and molybdenum trioxide powder or a mixture of about 50 wt % aluminum powder having an outer coating of aluminum oxide and polytetrafluoroethylene powder. The aluminum powder, molybdenum trioxide powder and polytetrafluoroethylene powder has a particle size of 0.1 .mu.m or less, more preferably a particle size of from about 200-500 angstroms.

  7. Proceedings of the 2007 Aging Aircraft Conference Cost Model for Assessing the Transition to Lead-Free Electronics

    E-Print Network [OSTI]

    Sandborn, Peter

    Proceedings of the 2007 Aging Aircraft Conference Cost Model for Assessing the Transition to Lead the cost ramifications of the transition from tin- lead to lead-free electronic parts. All tin-lead, all lead-free and mixed assembly approaches are considered. The model makes basic assumptions of a fixed

  8. Nano-soldering to single atomic layer

    DOE Patents [OSTI]

    Girit, Caglar O. (Berkeley, CA); Zettl, Alexander K. (Kensington, CA)

    2011-10-11

    A simple technique to solder submicron sized, ohmic contacts to nanostructures has been disclosed. The technique has several advantages over standard electron beam lithography methods, which are complex, costly, and can contaminate samples. To demonstrate the soldering technique graphene, a single atomic layer of carbon, has been contacted, and low- and high-field electronic transport properties have been measured.

  9. Dielectric and piezoelectric properties of sodium lithium niobate Na1-xLixNbO3 lead free ferroelectric ceramics

    E-Print Network [OSTI]

    Cao, Wenwu

    ferroelectric ceramics G. R. Li & Q. R. Yin & L. Y. Zheng Y. Y. Guo & W. W. Cao Published online: 17 May 2007 curves of LNN ceramics showed that there exist three phase transitions from room temperature up. The solid solution NaxLi1-xNbO3 (LNN) ceramics is a very interest- ing material due to its lead free

  10. SU-E-P-09: Radiation Transmission Measurements and Evaluation of Diagnostic Lead-Based and Lead-Free Aprons

    SciTech Connect (OSTI)

    Syh, J

    2014-06-01

    Purpose: This study was conducted to ensure that various lead shield apron manufacturers provided accurate attenuation factors regardless of whether the apron was made of lead-based or lead-free equivalent material. Methods: A calibrated ionization survey meter was placed at chest height and 36 cm horizontally away from a solid water phantom on a simulator couch. Measurements were done with or without apron. Radiation field was set to 24cmx24cm with the phantom at 100cm source-to-surface distance. Irradiation time was set for 1 minute at voltages of 60, 80, 100 and 120 kVp. Current was set at 6mA. Results: Between 60 kVp and 120 kVp, the transmission through 0.50 mm of lead-based apron was between 1.0% and 6.5% with a mean value of 3.2% and a standard deviation (s.d.) of 1.4%. The transmissions through the 0.50 mm lead-free aprons were 1.0 % to 12.0% with a mean value of 6.1% and s.d. of 2.6%. At 120 kVp, the transmission value was 6.5% for 0.50 mm lead-based apron and 11.1% to 12.0% for 0.50 mm lead-free aprons. The radiation transmissions at 80 kVp, measured in two different 0.5 mm lead-free aprons, were 4.3% each. However, only 1.4% transmission was found through the lead-based apron. Overall, the radiation transmitted through the lead-based apron was 1/3 transmission of lead-free at 80kVp, and half value of lead-free aprons at 100 and 120 kVp. Conclusion: Even though lead-based and lead-free aprons all claimed to have the same lead equivalent thickness, the transmission might not be the same. The precaution was needed to exercise diligence in quality assurance program to assure adequate protection to staff who wear it during diagnostic procedures. The requirement for aprons not only should be in certain thickness to meet state regulation but also to keep reasonably achievable low exposure with the accurate labeling from manufacturers.

  11. An Accelerated Method for Testing Soldering Tendency of Core Pins

    SciTech Connect (OSTI)

    Han, Qingyou [ORNL; Xu, Hanbing [ORNL; Ried, Paul [Ried, Engineering; Olson, Paul [Balzers, Inc.

    2010-01-01

    An accelerated method for testing die soldering has been developed. High intensity ultrasonic vibrations has been used to simulate the die casting conditions such as high pressure and high impingement speed of molten metal on the pin. Soldering tendency of steels and coated pins has been examined. The results indicate that in the low carbon steel/Al system, the onset of soldering is 60 times faster with ultrasonic vibration than that without ultrasonic vibration. In the H13/A380 system, the onset of soldering reaction is accelerated to 30-60 times. Coating significantly reduces the soldering tendency of the core pins.

  12. Solder for oxide layer-building metals and alloys

    DOE Patents [OSTI]

    Kronberg, J.W.

    1992-09-15

    A low temperature solder and method for soldering an oxide layer-building metal such as aluminum, titanium, tantalum or stainless steel is disclosed. The composition comprises tin and zinc; germanium as a wetting agent; preferably small amounts of copper and antimony; and a grit, such as silicon carbide. The grit abrades any oxide layer formed on the surface of the metal as the germanium penetrates beneath and loosens the oxide layer to provide good metal-to-metal contact. The germanium comprises less than approximately 10% by weight of the solder composition so that it provides sufficient wetting action but does not result in a melting temperature above approximately 300 C. The method comprises the steps rubbing the solder against the metal surface so the grit in the solder abrades the surface while heating the surface until the solder begins to melt and the germanium penetrates the oxide layer, then brushing aside any oxide layer loosened by the solder.

  13. Solder for oxide layer-building metals and alloys

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1992-01-01

    A low temperature solder and method for soldering an oxide layer-building metal such as aluminum, titanium, tantalum or stainless steel. The comosition comprises tin and zinc; germanium as a wetting agent; preferably small amounts of copper and antimony; and a grit, such as silicon carbide. The grit abrades any oxide layer formed on the surface of the metal as the germanium penetrates beneath and loosens the oxide layer to provide good metal-to-metal contact. The germanium comprises less than aproximatley 10% by weight of the solder composition so that it provides sufficient wetting action but does not result in a melting temperature above approximately 300.degree. C. The method comprises the steps rubbing the solder against the metal surface so the grit in the solder abrades the surface while heating the surface until the solder begins to melt and the germanium penetrates the oxide layer, then brushing aside any oxide layer loosened by the solder.

  14. Aging Effects on the Microstructure, Surface Characteristics and Wettability of Cu Pretinned with Sn-Pb Solders

    E-Print Network [OSTI]

    Linch, H.S.

    2010-01-01

    Chairman, "Accelerated Aging for Solderability EvaluationsA Survey of Accelerated Aging Techniques for SolderableJ. K. ,andG. J. Davis,"Aging Solder hickness Solder lloy T

  15. University of California, Irvine Environmental Health and Safety www.ehs.uci.edu Questions Call: (949) 824-6200 Version 1.0 Lead Free UCI

    E-Print Network [OSTI]

    George, Steven C.

    : (949) 824-6200 Version 1.0 Lead Free UCI Autoclave Tape - Get the Lead Out Environmental Health risks of lead pollution, and Replace lead containing autoclave tape with lead-free autoclave tape for FREE. Autoclave tape used in some laboratories may contain levels of lead that exceed the hazardous

  16. Piezoelectric and ferroelectric properties of lead-free niobium-rich potassium lithium tantalate niobate single crystals

    SciTech Connect (OSTI)

    Li, Jun, E-mail: lijuna@hit.edu.cn [Department of Physics, Harbin Institute of Technology, Harbin 150001 (China); Li, Yang [Department of chemistry, Harbin Institute of Technology, Harbin 150001 (China); Zhou, Zhongxiang [Department of Physics, Harbin Institute of Technology, Harbin 150001 (China); Guo, Ruyan; Bhalla, Amar S. [Multifunctional Electronic Materials and Device Research Lab, Department of Electrical and Computer Engineering, The University of Texas at San Antonio, San Antonio 78249 (United States)

    2014-01-01

    Graphical abstract: - Highlights: • Lead-free K{sub 0.95}Li{sub 0.05}Ta{sub 1?x}Nb{sub x}O{sub 3} single crystals were grown using the top-seeded melt growth method. • The piezoelectric and ferroelectric properties of as-grown crystals were systematically investigated. • The piezoelectric properties are very attractive, e.g. for x = 0.60 composition, k{sub t} ? 70%, k{sub 31} ? 70%, k{sub 33} ? 77%, d{sub 31} ? 230 pC/N, d{sub 33} ? 600 pC/N. • The coercive fields of P–E hysteresis loops are quite small, about or less than 1 kV/mm. - Abstract: Lead-free potassium lithium tantalate niobate single crystals with the composition of K{sub 0.95}Li{sub 0.05}Ta{sub 1?x}Nb{sub x}O{sub 3} (abbreviated as KLTN, x = 0.51, 0.60, 0.69, 0.78) were grown using the top-seeded melt growth method. Their piezoelectric and ferroelectric properties in as-grown crystals have been systematically investigated. The phase transitions and Curie temperatures were determined from dielectric and pyroelectric measurements. Piezoelectric coefficients and electromechanical coupling factors in thickness mode, length-extensional mode and longitudinal mode were obtained. The piezoelectric properties are very attractive, e.g. for x = 0.60 composition, k{sub t} ? 70%, k{sub 31} ? 70%, k{sub 33} ? 77%, d{sub 31} ? 230 pC/N, d{sub 33} ? 600 pC/N are comparable to the lead-based PZT composition. The polarization versus electric field hysteresis loops show saturated shapes. In short, lead-free niobium-rich KLTN system possesses comparable properties to those in important lead-based piezoelectric material nowadays.

  17. Dry soldering with hot filament produced atomic hydrogen

    DOE Patents [OSTI]

    Panitz, Janda K. G. (Edgewood, NM); Jellison, James L. (Albuquerque, NM); Staley, David J. (Los Lunas, NM)

    1995-01-01

    A system for chemically transforming metal surface oxides to metal that is especially, but not exclusively, suitable for preparing metal surfaces for dry soldering and solder reflow processes. The system employs one or more hot, refractory metal filaments, grids or surfaces to thermally dissociate molecular species in a low pressure of working gas such as a hydrogen-containing gas to produce reactive species in a reactive plasma that can chemically reduce metal oxides and form volatile compounds that are removed in the working gas flow. Dry soldering and solder reflow processes are especially applicable to the manufacture of printed circuit boards, semiconductor chip lead attachment and packaging multichip modules. The system can be retrofitted onto existing metal treatment ovens, furnaces, welding systems and wave soldering system designs.

  18. Dry soldering with hot filament produced atomic hydrogen

    DOE Patents [OSTI]

    Panitz, J.K.G.; Jellison, J.L.; Staley, D.J.

    1995-04-25

    A system is disclosed for chemically transforming metal surface oxides to metal that is especially, but not exclusively, suitable for preparing metal surfaces for dry soldering and solder reflow processes. The system employs one or more hot, refractory metal filaments, grids or surfaces to thermally dissociate molecular species in a low pressure of working gas such as a hydrogen-containing gas to produce reactive species in a reactive plasma that can chemically reduce metal oxides and form volatile compounds that are removed in the working gas flow. Dry soldering and solder reflow processes are especially applicable to the manufacture of printed circuit boards, semiconductor chip lead attachment and packaging multichip modules. The system can be retrofitted onto existing metal treatment ovens, furnaces, welding systems and wave soldering system designs. 1 fig.

  19. RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS Kyunghan Kim to incorporate transient radiation heat transfer in tissue welding and soldering with use of ultrafast lasers are performed between laser welding and laser soldering. The use of solder is found to substantially enhance

  20. Hot-stage transmission electron microscopy study of (Na, K)NbO{sub 3} based lead-free piezoceramics

    SciTech Connect (OSTI)

    Lu, Shengbo; Xu, Zhengkui; Kwok, K. W.; Chan, Helen L. W.

    2014-07-28

    Hierarchical nanodomains assembled into micron-sized stripe domains, which is believed to be associated with outstanding piezoelectric properties, were observed at room temperature in a typical lead free piezoceramics, (Na{sub 0.52}K{sub 0.48?x})(Nb{sub 0.95?x}Ta{sub 0.05})-xLiSbO{sub 3}, with finely tuned polymorphic phase boundaries (x?=?0.0465) by transmission electron microscopy. The evolution of domain morphology and crystal structure under heating and cooling cycles in the ceramic was investigated by in-situ hot stage study. It is found that the nanodomains are irreversibly transformed into micron-sized rectangular domains during heating and cooling cycles, which lead to the thermal instability of piezoelectric properties of the materials.

  1. Mechanical confinement for improved energy storage density in BNT-BT-KNN lead-free ceramic capacitors

    SciTech Connect (OSTI)

    Chauhan, Aditya; Patel, Satyanarayan; Vaish, Rahul

    2014-08-15

    With the advent of modern power electronics, embedded circuits and non-conventional energy harvesting, the need for high performance capacitors is bound to become indispensible. The current state-of-art employs ferroelectric ceramics and linear dielectrics for solid state capacitance. However, lead-free ferroelectric ceramics propose to offer significant improvement in the field of electrical energy storage owing to their high discharge efficiency and energy storage density. In this regards, the authors have investigated the effects of compressive stress as a means of improving the energy storage density of lead-free ferroelectric ceramics. The energy storage density of 0.91(Bi{sub 0.5}Na{sub 0.5})TiO{sub 3}-0.07BaTiO{sub 3}-0.02(K{sub 0.5}Na{sub 0.5})NbO{sub 3} ferroelectric bulk ceramic was analyzed as a function of varying levels of compressive stress and operational temperature .It was observed that a peak energy density of 387 mJ.cm{sup -3} was obtained at 100 MPa applied stress (25{sup o}C). While a maximum energy density of 568 mJ.cm{sup -3} was obtained for the same stress at 80{sup o}C. These values are indicative of a significant, 25% and 84%, improvement in the value of stored energy compared to an unloaded material. Additionally, material's discharge efficiency has also been discussed as a function of operational parameters. The observed phenomenon has been explained on the basis of field induced structural transition and competitive domain switching theory.

  2. Droplet Bouncing Behavior in the Direct Solder Bumping Process

    E-Print Network [OSTI]

    Hsiao, Wayne

    This paper presents the results of an ongoing effort to develop a direct solder bumping process for electronics packaging. The proposed process entails delivering molten droplets onto specific locations on electronic devices ...

  3. Substrate solder barriers for semiconductor epilayer growth

    DOE Patents [OSTI]

    Drummond, Timothy J. (Tijeras, NM); Ginley, David S. (Albuquerque, NM); Zipperian, Thomas E. (Albuquerque, NM)

    1989-01-01

    During the growth of compound semiconductors by epitaxial processes, substrates are typically mounted to a support. In modular beam epitaxy, mounting is done using indium as a solder. This method has two drawbacks: the indium reacts with the substrate, and it is difficult to uniformly wet the back of a large diameter substrate. Both of these problems have been successfully overcome by sputter coating the back of the substrate with a thin layer of tungsten carbide or tungsten carbide and gold. In addition to being compatible with the growth of high quality semiconductor epilayers this coating is also inert in all standard substrate cleaning etchants used for compound semiconductors, and provides uniform distribution of energy in radiant heating.

  4. Structural, microstructural and thermal properties of lead-free bismuth–sodium–barium–titanate piezoceramics synthesized by mechanical alloying

    SciTech Connect (OSTI)

    Amini, Rasool; Ghazanfari, Mohammad Reza; Alizadeh, Morteza; Ardakani, Hamed Ahmadi; Ghaffari, Mohammad

    2013-02-15

    Graphical abstract: Mechano-synthesis of lead-free (Bi{sub 0.5}Na{sub 0.5}){sub 0.94}Ba{sub 0.06}TiO{sub 3} piezoceramics with nanocrystalline/amorphous structure and homogeneous composition: partial transformation of constituents to BNBT, BNT and pyrochlore, amorphous phase formation, mechano-crystallization of the amorphous, pyrochlore-to-perovskite BNBT phase transformation during the process. Display Omitted Highlights: ? Perovskite BNBT powders with homogeneous composition were synthesized by MA. ? Partial transformation of constituents to BNBT, BNT and pyrochlore occurred by MA. ? Formation of an amorphous phase and afterwards its crystallization occurred by MA. ? Pyrochlore-to-perovskite BNBT phase transformation occurred after prolong milling. ? Polymorphic transformations of TiO{sub 2} act as the main alloying impediment during MA. -- Abstract: Bismuth–sodium–barium–titanate piezoceramics with a composition of (Bi{sub 0.5}Na{sub 0.5}){sub 0.94}Ba{sub 0.06}TiO{sub 3} (BNBT) were prepared by mechanical alloying (MA). Structural analysis and phase identification were performed by X-ray diffraction (XRD). Microstructural studies and chemical composition homogeneity were performed by scanning electron microscope (SEM) coupled with energy dispersive X-ray analysis (EDX). Furthermore, thermal properties of the as-milled powders were evaluated by thermogravimetry/differential thermal analysis (TG/DTA). During the initial milling, the constituents were transformed to the perovskite, pyrochlore, and BNT phases; in addition, partial amorphization of the structure appeared during the milling cycle. As MA progressed, transformation of pyrochlore-to-perovskite and crystallization of the amorphous phase occurred and also, the BNBT phase was significantly developed. It was found that the MA process has the ability to synthesize the BNBT powders with a submicron particle size, regular morphology, and uniform elemental distribution.

  5. Phase transition behavior and high piezoelectric properties in lead-free BaTiO3CaTiO3BaHfO3 ceramics

    E-Print Network [OSTI]

    Cao, Wenwu

    ceramics Dali Wang · Zhaohua Jiang · Bin Yang · Shantao Zhang · Mingfu Zhang · Feifei Guo · Wenwu Cao of lead-free (1-x)Ba(Hf0.16Ti0.84)O3­x (Ba0.70Ca0.30)TiO3 (BCHT) ceramics fabricated by the conventional been proposed based on their dielectric behavior. It is found that BHCT ceramics undergo a complicated

  6. Porosity in collapsible Ball Grid Array solder joints

    SciTech Connect (OSTI)

    Gonzalez, C.A. |

    1998-05-01

    Ball Grid Array (BGA) technology has taken off in recent years due to the increased need for high interconnect density. Opposite to all the advantages BGA packages offer, porosity in collapsible BGA solder joints is often a major concern in the reliability of such packages. The effect of pores on the strength of collapsible BGA solder-joints was studied by manufacturing samples with different degrees of porosity and testing them under a shear load. It was found that the shear strength of the solder joints decreased in a linear fashion with increasing porosity. Failure occurred by internal necking of the interpore matrix. It was confirmed that entrapment of flux residues leads to porosity by manufacturing fluxless samples in a specially made furnace, and comparing them with samples assembled using flux. Also, contamination of Au electrodeposits (in substrate metallization) was determined to cause significant porosity. It was found that hard-Au (Co hardened Au) electrodeposits produce high degrees of porosity even in the absence of flux. Finally, increasing the time the solder spends in the molten state was proven to successfully decrease porosity.

  7. In situ measurement of electromigration-induced transient stress in Pb-free Sn-Cu solder joints by synchrotron radiation based X-ray polychromatic microdiffraction

    E-Print Network [OSTI]

    Chen, Kai

    2009-01-01

    elastic stress in Pb-free SnCu solder joints was studied byeffective charge number for SnCu solder is calculated and

  8. In situ measurement of electromigration-induced transient stress in Pb-free Sn-Cu solder joints by synchrotron radiation based X-ray polychromatic microdiffraction

    E-Print Network [OSTI]

    Chen, Kai

    2011-01-01

    elastic stress in Pb-free SnCu solder joints was studied byeffective charge number for SnCu solder is calculated and

  9. Aging Effects on the Microstructure, Surface Characteristics and Wettability of Cu Pretinned with Sn-Pb Solders

    E-Print Network [OSTI]

    Linch, H.S.

    2010-01-01

    solders. Coatings were applied using electroplating or hotcoatings are usually Sn-Pb solders and are often applied to Cu substrates using electroplatingdipped coatings. [9] Based on these ranges, electroplating

  10. Method and apparatus for jetting, manufacturing and attaching uniform solder balls

    DOE Patents [OSTI]

    Yost, Frederick G. (Cedar Crest, NM); Frear, Darrel R. (Albuquerque, NM); Schmale, David T. (Albuquerque, NM)

    1999-01-01

    An apparatus and process for jetting molten solder in the form of balls directly onto all the metallized interconnects lands for a ball grid array package in one step with no solder paste required. Molten solder is jetted out of a grid of holes using a piston attached to a piezoelectric crystal. When voltage is applied to the crystal it expands forcing the piston to extrude a desired volume of solder through holes in the aperture plate. When the voltage is decreased the piston reverses motion creating an instability in the molten solder at the aperture plate surface and thereby forming spherical solder balls that fall onto a metallized substrate. The molten solder balls land on the substrate and form a metallurgical bond with the metallized lands. The size of the solder balls is determined by a combination of the size of the holes in the aperture plate, the duration of the piston pulse, and the displacement of the piston. The layout of the balls is dictated by the location of the hooks in the grid. Changes in ball size and layout can be easily accomplished by changing the grid plate. This invention also allows simple preparation of uniform balls for subsequent supply to BGA users.

  11. Relaxor nature in lead-free Sr{sub 5}LaTi{sub 3}Nb{sub 7}O{sub 30} tetragonal tungsten bronze ceramics

    SciTech Connect (OSTI)

    Li Zhu, Xiao; Department of Materials and Ceramic Engineering, Centre for Research in Ceramics and Composite Materials, CICECO, University of Aveiro, 3810-193 Aveiro ; Li, Kun; Qiang Liu, Xiao; Ming Chen, Xiang; Asif Rafiq, Muhammad

    2013-09-28

    Lead-free tetragonal tungsten bronze Sr{sub 5}LaTi{sub 3}Nb{sub 7}O{sub 30} ceramics were prepared and the correlation of the relaxor nature and crystal structure was studied using dielectric spectroscopy and powder X-ray diffraction. Three dielectric relaxations were observed below the deviation temperature T{sub D}? 330 K. Relaxation I and II followed the Vogel-Fulcher law with the freezing temperatures of 189 K and ?90 K. Low temperature relaxation III, which was first observed in filled tungsten bronze, followed well the Arrhenius law. Dielectric response becomes static below 50 K. Polarization-field (P-E) hysteresis loops were evaluated from 183 K to 298 K. P{sub r} value of 0.41?C/cm{sup 2} was observed at 183 K. Deviation of lattice parameter c from the linear contraction and increasing of tetragonality (c/a ratio) were observed below T{sub D}, reflecting the structure change during the formation of polar nanoregions and the following freezing process. Opposite tendency was observed below 100 K for all the lattice parameters, corresponding to relaxation III. Generally, the main dielectric relaxation I and II were attributed to flipping and breathing of polar nanoregions along c axis, while the concerted rotations of the oxygen octahedra in the ab plane were suggested as the origin of relaxation III.

  12. Effects of surface properties on solder bump formation by direct droplet deposition

    E-Print Network [OSTI]

    Hsiao, Wen Kai, 1972-

    2004-01-01

    Recent advances in microdroplet generation and deposition processes have made it possible to directly form solder bumps on integrated circuits using micron-sized molten metal droplets. The direct droplet deposition bumping ...

  13. Root cause analysis of solder flux residue incidence in the manufacture of electronic power modules

    E-Print Network [OSTI]

    Jain, Pranav

    2011-01-01

    This work investigates the root causes of the incidence of solder flux residue underneath electronic components in the manufacture of power modules. The existing deionized water-based centrifugal cleaning process was ...

  14. Understanding, Modeling and Predicting Hidden Solder Joint Shape Using Active Thermography 

    E-Print Network [OSTI]

    Giron Palomares, Jose

    2012-07-16

    Characterizing hidden solder joint shapes is essential for electronics reliability. Active thermography is a methodology to identify hidden defects inside an object by means of surface abnormal thermal response after applying a heat flux...

  15. Modeling and implementation of solder-activated joints for single actuator, centimeter-scale robotic mechanisms

    E-Print Network [OSTI]

    Telleria, Maria J

    2010-01-01

    This thesis explains when, and why, solder-based phase change materials (PCMs) are best-suited as a means to modify a robotic mechanism's kinematic and elastomechanic behavior. The preceding refers to mechanisms that possess ...

  16. Evaluation of low-residue soldering for military and commercial applications: A report from the Low-Residue Soldering Task Force

    SciTech Connect (OSTI)

    Iman, R.L.; Anderson, D.J.; Burress, R.V.

    1995-06-01

    The LRSTF combined the efforts of industry, military, and government to evaluate low-residue soldering processes for military and commercial applications. These processes were selected for evaluation because they provide a means for the military to support the presidential mandate while producing reliable hardware at a lower cost. This report presents the complete details and results of a testing program conducted by the LRSTF to evaluate low-residue soldering for printed wiring assemblies. A previous informal document provided details of the test plan used in this evaluation. Many of the details of that test plan are contained in this report. The test data are too massive to include in this report, however, these data are available on disk as Excel spreadsheets upon request. The main purpose of low-residue soldering is to eliminate waste streams during the manufacturing process.

  17. Get the LEAD Out!Most lead-containing autoclave tape has stripes running across at an angle ( / / / / / / ); if it has very faint text (the word "autoclaved"), it most likely is a lead-free alternative.

    E-Print Network [OSTI]

    Ford, James

    Get the LEAD Out!Most lead-containing autoclave tape has stripes running across at an angle ( / / / / / / ); if it has very faint text (the word "autoclaved"), it most likely is a lead-free alternative. ADDITIONAL Programs Office (650.723.0110) REPLACE lead-containing rolls of auto- clave tape with a non-lead containing

  18. Giant strain with ultra-low hysteresis and high temperature stability in grain oriented lead-free K???Bi???TiO?-BaTiO?-Na???Bi???TiO? piezoelectric materials

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

    Maurya, Deepam; Zhou, Yuan; Wang, Yaojin; Yan, Yongke; Li, Jiefang; Viehland, Dwight; Priya, Shashank

    2015-02-26

    We synthesized grain-oriented lead-free piezoelectric materials in (K???Bi???TiO?-BaTiO?-xNa???Bi???TiO? (KBT-BT-NBT) system with high degree of texturing along the [001]c (c-cubic) crystallographic orientation. We demonstrate giant field induced strain (~0.48%) with an ultra-low hysteresis along with enhanced piezoelectric response (d?? ~ 190pC/N) and high temperature stability (~160°C). Transmission electron microscopy (TEM) and piezoresponse force microscopy (PFM) results demonstrate smaller size highly ordered domain structure in grain-oriented specimen relative to the conventional polycrystalline ceramics. The grain oriented specimens exhibited a high degree of non-180° domain switching, in comparison to the randomly axed ones. These results indicate the effective solution to the lead-free piezoelectricmore »materials.« less

  19. Electromigration-induced back stress in critical solder length for three-dimensional integrated circuits

    SciTech Connect (OSTI)

    Huang, Y. T.; Hsu, H. H.; Wu, Albert T., E-mail: atwu@ncu.edu.tw [Department of Chemical and Materials Engineering, National Central University, Jhongli City 320, Taiwan (China)

    2014-01-21

    Because of the miniaturization of electronic devices, the reliability of electromigration has become a major concern when shrinking the solder dimensions in flip-chip joints. Fast reaction between solders and electrodes causes intermetallic compounds (IMCs) to form, which grow rapidly and occupy entire joints when solder volumes decrease. In this study, U-grooves were fabricated on Si chips as test vehicles. An electrode-solder-electrode sandwich structure was fabricated by using lithography and electroplating. Gaps exhibiting well-defined dimensions were filled with Sn3.5Ag solders. The gaps between the copper electrodes in the test sample were limited to less than 15??m to simulate microbumps. The samples were stressed at various current densities at 100?°C, 125?°C, and 150?°C. The morphological changes of the IMCs were observed, and the dimensions of the IMCs were measured to determine the kinetic growth of IMCs. Therefore, this study focused on the influence of back stress caused by microstructural evolution in microbumps.

  20. Morphotropic phase boundary and electric properties in (1-x)Bi0.5Na0.5TiO3-xBiCoO3 lead-free piezoelectric ceramics

    E-Print Network [OSTI]

    Cao, Wenwu

    -free piezoelectric ceramics Fei-Fei Guo, Bin Yang, Shan-Tao Zhang, Xiao Liu, Li-Mei Zheng et al. Citation: J. Appl ceramics Appl. Phys. Lett. 101, 252905 (2012) Enhanced piezoelectric performance from carbon fluoropolymer phase boundary and electric properties in (12x)Bi0.5Na0.5TiO3-xBiCoO3 lead-free piezoelectric ceramics

  1. The role of eddy currents and nanoparticle size on AC magnetic fieldinduced reflow in solder/magnetic nanocomposites

    E-Print Network [OSTI]

    McHenry, Michael E.

    The role of eddy currents and nanoparticle size on AC magnetic field­induced reflow in solder://jap.aip.org/about/rights_and_permissions #12;The role of eddy currents and nanoparticle size on AC magnetic field­induced reflow in solder be derived from eddy current losses in Cu planes in the substrate board. Eddy current heating in Cu sheets

  2. Design of Experiments to Determine Causes of Flex Cable Solder Wicking, Discoloration and Hole Location Defects

    SciTech Connect (OSTI)

    Wolfe, Larry

    2009-04-22

    Design of Experiments (DoE) were developed and performed in an effort to discover and resolve the causes of three different manufacturing issues; large panel voids after Hot Air Solder Leveling (HASL), cable hole locations out of tolerance after lamination and delamination/solder wicking around flat flex cable circuit lands after HASL. Results from a first DoE indicated large panel voids could be eliminated by removing the pre-HASL cleaning. It also revealed eliminating the pre-HASL bake would not be detrimental when using a hard press pad lamination stackup. A second DoE indicated a reduction in hard press pad stackup lamination pressure reduced panel stretch in the y axis approximately 70%. A third DoE illustrated increasing the pre-HASL bake temperature could reduce delamination/solder wicking when using a soft press pad lamination stackup.

  3. A novel photovoltaic-module assembly system for back contact solar cells using laser soldering technique

    E-Print Network [OSTI]

    lamination foil and solders the interconnectors to the cells using a laser. Our newly developed prototype on the interconnector (e.g. Pin up Module) [8] or an insulation on the cell itself (busbarless emitter warp through) [9]. Other cell designs require a conventional ribbon or must have a special bone shaped interconnector. Thus

  4. A MODIFIED ENERGY-BASED LOW CYCLE FATIGUE MODEL FOR EUTECTIC SOLDER ALLOY

    E-Print Network [OSTI]

    Zhou, Wei

    the component and the board. Fatigue failure of solder joints is recognized as a major cause of failure was carefully ground on fine SiC paper and polished using 1 m diamond paste. Afterwards, the fatigue specimens tests were conducted on a servo-valve-controlled electro-hydraulic testing machine newly designed by MTS

  5. Damage mechanics characterization on fatigue behavior of a solder joint material

    SciTech Connect (OSTI)

    Chow, C.L.; Yang, F. [Univ. of Michigan, Dearborn, MI (United States). Dept. of Mechanical Engineering; Fang, H.E. [Sandia National Labs., Albuquerque, NM (United States). Computational Physics Dept.

    1998-08-01

    This paper presents the first part of a comprehensive mechanics approach capable of predicting the integrity and reliability of solder joint material under fatigue loading without viscoplastic damage considerations. A separate report will be made to present a comprehensive damage model describing life prediction of the solder material under thermomechanical fatigue loading. The method is based on a theory of damage mechanics which makes possible a macroscopic description of the successive material deterioration caused by the presence of microcracks/voids in engineering materials. A damage mechanics model based on the thermodynamic theory of irreversible processes with internal state variables is proposed and used to provide a unified approach in characterizing the cyclic behavior of a typical solder material. With the introduction of a damage effect tensor, the constitutive equations are derived to enable the formulation of a fatigue damage dissipative potential function and a fatigue damage criterion. The fatigue evolution is subsequently developed based on the hypothesis that the overall damage is induced by the accumulation of fatigue and plastic damage. This damage mechanics approach offers a systematic and versatile means that is effective in modeling the entire process of material failure ranging from damage initiation and propagation leading eventually to macro-crack initiation and growth. As the model takes into account the load history effect and the interaction between plasticity damage and fatigue damage, with the aid of a modified general purpose finite element program, the method can readily be applied to estimate the fatigue life of solder joints under different loading conditions.

  6. Modeling and implementation of solder-activated joints for single-actuator, centimeter-scale robotic mechanisms

    E-Print Network [OSTI]

    Telleria, Maria J.

    We explain when, and why, solder-based phase change materials (PCMs) are best-suited as a means to modify a robotic mechanism's kinematic and elastomechanic behavior. The preceding refers to mechanisms that possess joints ...

  7. LCD, low-temperature soldering and compound semiconductor : the sources, market, applications and future prospects of indium in Malaysia

    E-Print Network [OSTI]

    Yong, Foo Nun

    2006-01-01

    Indium is a minor but very valuable metal. Decreasing supplies of indium from refining and increasing demands from LCD, low-temperature soldering and compound semiconductors have stimulated the indium price increase ...

  8. Effects of residual impurities in electroplated Cu on the Kirkendall void formation during soldering

    SciTech Connect (OSTI)

    Kim, J. Y.; Yu Jin [Department of Materials Science and Engineering, KAIST, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2008-03-03

    Additions of bis-(sodium sulfopropyl)-disulfide (SPS) to the Cu electroplating bath strongly affected the characteristics of Kirkendall void formation when the Cu film is soldered with Sn-3.5Ag solder and subsequently aged. Voids were predominantly distributed near the Cu{sub 3}Sn/Cu interface with SPS, but randomly distributed in the Cu{sub 3}Sn layer without SPS. In situ Auger electron spectroscopy of voids at the Cu{sub 3}Sn/Cu interface revealed surface segregation of S atoms, which came from SPS put into the bath as an additive. The S segregation to Cu{sub 3}Sn/Cu interface lowers the interface energy, thereby accelerating the void nucleation. Assisted by the high surface diffusivity of Cu and the presence of excess vacancies arising from the Kirkendall effect, voids tend to localize at the interface, which would result in serious degradation of the joint reliability.

  9. Appendix to the report from the low-residue soldering task force: Phase 2 results

    SciTech Connect (OSTI)

    Iman, R.L.; Anderson, D.J.; Huffman, D.D. [and others

    1995-12-01

    The LRSTF report for Phase I of its evaluation of low-residue soldering was issued in June 1995. This Appendix summarizes the results of follow-on testing performed in Phase II and compares electrical test results for both phases. Deliberate decisions were made by the LRSTF in Phase I to challenge the design guideline limits in MILSTD-275, Printed Wiring for Electronic Equipment The LRSTF considered this approach to produce a ``worst case`` design and provide useful information about the robustness of LR soldering processes. As such, good design practices were sometimes deliberately violated in designing the LRSTF board. This approach created some anomalies for both LR boards and RMA/cleaned controls. Phase II testing verified that problems that affected both RMA/cleaned and LR boards in Phase I were design related.

  10. Dual-enhancement of ferro-/piezoelectric and photoluminescent performance in Pr{sup 3+} doped (K{sub 0.5}Na{sub 0.5})NbO{sub 3} lead-free ceramics

    SciTech Connect (OSTI)

    Wei, Yongbin; Jia, Yanmin E-mail: ymjia@zjnu.edu.cn; Wu, Jiang; Shen, Yichao; Wu, Zheng E-mail: ymjia@zjnu.edu.cn; Luo, Haosu

    2014-07-28

    A mutual enhancement action between the ferro-/piezoelectric polarization and the photoluminescent performance of rare earth Pr{sup 3+} doped (K{sub 0.5}Na{sub 0.5})NbO{sub 3} (KNN) lead-free ceramics is reported. After Pr{sup 3+} doping, the KNN ceramics exhibit the maximum enhancement of ?1.2 times in the ferroelectric remanent polarization strength and ?1.25 times in the piezoelectric coefficient d{sub 33}, respectively. Furthermore, after undergoing a ferro-/piezoelectric polarization treatment, the maximum enhancement of ?1.3 times in photoluminescence (PL) was observed in the poled 0.3% Pr{sup 3+} doped sample. After the trivalent Pr{sup 3+} unequivalently substituting the univalent (K{sub 0.5}Na{sub 0.5}){sup +}, A-sites ionic vacancies will occur to maintain charge neutrality, which may reduce the inner stress and ease the domain wall motions, yielding to the enhancement in ferro-/piezoelectric performance. The polarization-induced enhancement in PL is attributed to the decrease of crystal symmetry abound the Pr{sup 3+} ions after polarization. The dual-enhancement of the ferro-/piezoelectric and photoluminescent performance makes the Pr{sup 3+} doped KNN ceramic hopeful for piezoelectric/luminescent multifunctional devices.

  11. Process for reducing series resistance of solar cell metal contact systems with a soldering flux etchant

    DOE Patents [OSTI]

    Coyle, R. T. (Lakewood, CO); Barrett, Joy M. (Eldorado Springs, CO)

    1984-01-01

    Disclosed is a process for substantially reducing the series resistance of a solar cell having a thick film metal contact assembly thereon while simultaneously removing oxide coatings from the surface of the assembly prior to applying solder therewith. The process includes applying a flux to the contact assembly and heating the cell for a period of time sufficient to substantially remove the series resistance associated with the assembly by etching the assembly with the flux while simultaneously removing metal oxides from said surface of said assembly.

  12. Electrical properties of (1?x)(Bi{sub 0.5}Na{sub 0.5})TiO{sub 3}–xKNbO{sub 3} lead-free ceramics

    SciTech Connect (OSTI)

    Jiang, Xijie; Wang, Baoyin; Luo, Laihui; Li, Weiping; Zhou, Jun; Chen, Hongbing

    2014-05-01

    In this investigation, a simple compound (1?x)(Bi{sub 0.5}Na{sub 0.5})TiO{sub 3}–xKNbO{sub 3} (BNT–xKN, x=0–0.08) lead-free ceramics were synthesized successfully by conventional solid state reaction method. The piezoelectric, dielectric and ferroelectric characteristics of the ceramics were investigated and discussed. The results shows that moderate KN addition can enhance the piezoelectric response without an obvious decline of ferroelectric properties. The largest piezoelectric response is obtained in BNT–0.05KN, whereas largest electric-field-induced strain is obtained in BNT–0.06KN. An effective d{sub 33}{sup eff} of ?400 pC/N calculated from electric-field-induced strain is obtained in BNT–0.06KN. The present investigation demonstrates that addition KN effectively reduces the depolarization temperature of the BNT–xKN ceramics. The electrical properties of the ceramics are tightly related to their depolarization temperature. - Graphical abstract: Unipolar electric-field-induced strain for the BNT–xKN ceramics. A maximum strain of 0.28% is achieved with a low field in BNT–0.06KN. - Highlights: • Moderate KNbO{sub 3} addition enhances the piezoelectric properties of the ceramics. • A maximum strain of 0.28% is achieved with a low field. • A large piezoelectric response is achieved in 0.95(Bi{sub 0.5}Na{sub 0.5})TiO{sub 3}–0.05KNbO{sub 3}. • The electrical properties are tightly related to the depolarization temperature T{sub d}.

  13. Giant strain with ultra-low hysteresis and high temperature stability in grain oriented lead-free K0.5Bi0.5TiO3-BaTiO3-Na0.5Bi0.5TiO3 piezoelectric materials

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

    Maurya, Deepam; Zhou, Yuan; Wang, Yaojin; Yan, Yongke; Li, Jiefang; Viehland, Dwight; Priya, Shashank

    2015-02-26

    We synthesized grain-oriented lead-free piezoelectric materials in (K0.5Bi0.5TiO3-BaTiO3-Na0.5Bi0.5TiO3 (KBT-BT-NBT) system with high degree of texturing along the [001]c (c-cubic) crystallographic orientation. We demonstrate giant field induced strain (,0.48%) with an ultra-low hysteresis along with enhanced piezoelectric response (d33 , 190pC/N) and high temperature stability (,1606C). Transmission electron microscopy (TEM) and piezoresponse force microscopy (PFM) results demonstrate smaller size highly ordered domain structure in grain-oriented specimen relative to the conventional polycrystalline ceramics. The grain oriented specimens exhibited a high degree of non-1806 domain switching, in comparison to the randomly axed ones. These results indicate the effective solution to the lead-free piezoelectricmore »materials.« less

  14. An evaluation of the spring finger solder joints on SA1358-10 and SA2052-4 connector assemblies (MC3617,W87).

    SciTech Connect (OSTI)

    Kilgo, Alice C.; Vianco, Paul Thomas; Hlava, Paul Frank; Zender, Gary L.

    2006-08-01

    The SA1358-10 and SA2052-4 circular JT Type plug connectors are used on a number of nuclear weapons and Joint Test Assembly (JTA) systems. Prototype units were evaluated for the following specific defects associated with the 95Sn-5Sb (Sn-Sb, wt.%) solder joint used to attach the beryllium-copper (BeCu) spring fingers to the aluminum (Al) connector shell: (1) extended cracking within the fillet; (2) remelting of the solder joint during the follow-on, soldering step that attached the EMR adapter ring to the connector shell (and/or soldering the EMR shell to the adapter ring) that used the lower melting temperature 63Sn-37Pb (Sn-Pb) alloy; and (3) spalling of the Cd (Cr) layer overplating layer from the fillet surface. Several pedigrees of connectors were evaluated, which represented older fielded units as well as those assemblies that were recently constructed at Kansas City Plant. The solder joints were evaluated that were in place on connectors made with the current soldering process as well as an alternative induction soldering process for attaching the EMR adapter ring to the shell. Very similar observations were made, which crossed the different pedigrees of parts and processes. The extent of cracking in the top side fillets varied between the different connector samples and likely the EMR adapter ring to the shell. Very similar observations were made, which crossed the different pedigrees of parts and processes. The extent of cracking in the top side fillets varied between the different connector samples and likely reflected the different extents to which the connector was mated to its counterpart assembly. In all cases, the spring finger solder joints on the SA1358-10 connectors were remelted as a result of the subsequent EMR adapter ring attachment process. Spalling of the Cd (Cr) overplating layer was also observed for these connectors, which was a consequence of the remelting activity. On the other hand, the SA2052-4 connector did not exhibit evidence of remelting of the spring finger solder joint. The Cd (Cr) layer did not show signs of spalling. These results suggested that, due to the size of the SA1358-10 connector, any of the former or current soldering processes used to attach the EMR adapter ring and/or EMR shell to the connector shell, requires a level of heat energy that will always result in the remelting of the spring finger solder joint attached with either the Sn-Ag or the Sn-Sb alloy. Lastly, it was construed that the induction soldering process, which is used to attach the EMR adapter ring onto the shell, was more likely to have caused the remelting event rather than the more localized heat source of the hand soldering iron used to attach the EMR shell to the adapter ring.

  15. Contributions Of Stress And Oxidation On The Formation Of Whiskers In Pb-Free Solders

    SciTech Connect (OSTI)

    Duncan, A. J.; Hoffman, E. N.

    2014-03-25

    This report summarizes the research activities of WP-1754. The study focusses on the environmental factors influencing formation of lead free whiskers on electrodeposited tin coatings over copper (or copper containing) substrates. Much of the initial results are summarized in an interim report. From the initial results, two main areas were chosen to be the focus of additional research: the demonstration of effects of elastic stress state in the nucleation of whiskers and the confirmation of the effect of oxygen/nitrogen ratio in the formation of whiskers. Different levels of elastic stress were induced with the incorporation of a custom designed fixture that loaded the substrates in a four-point bending configuration and were maintained in an environmental chamber under conditions deemed favorable for whisker growth. The results show that induced elastic stress slightly increased the concentration of nucleation sites of whiskers. The effects of oxygen content were studied by aging substrates in gas vials of varying absolute pressure and different oxygen/nitrogen ratios. The concentration of whiskers were measured and appear to be sensitive to absolute pressure but are not sensitive to oxygen content (as previously observed).

  16. Gelatin based on Power-gel.TM. as solders for Cr.sup.4+laser tissue welding and sealing of lung air leak and fistulas in organs

    DOE Patents [OSTI]

    Alfano, Robert R.; Tang, Jing; Evans, Jonathan M.; Ho, Peng Pei

    2006-04-25

    Laser tissue welding can be achieved using tunable Cr.sup.4+ lasers, semiconductor lasers and fiber lasers, where the weld strength follows the absorption spectrum of water. The use of gelatin and esterified gelatin as solders in conjunction with laser inducted tissue welding impart much stronger tensile and torque strengths than albumin solders. Selected NIR wavelength from the above lasers can improve welding and avoid thermal injury to tissue when used alone or with gelatin and esterified gelatin solders. These discoveries can be used to enhance laser tissue welding of tissues such as skin, mucous, bone, blood vessel, nerve, brain, liver, pancreas, spleen, kidney, lung, bronchus, respiratory track, urinary tract, gastrointestinal tract, or gynecologic tract and as a sealant for pulmonary air leaks and fistulas such as intestinal, rectal and urinary fistulas.

  17. A new Bi{sub 0.5}Na{sub 0.5}TiO{sub 3} based lead-free piezoelectric system with calculated end-member Bi(Zn{sub 0.5}Hf{sub 0.5})O{sub 3}

    SciTech Connect (OSTI)

    Liu, Feng; Wahyudi, Olivia; Li, Yongxiang

    2014-03-21

    The phase structure, dielectric and piezoelectric properties of a new lead-free piezoelectric system (1???x)Bi{sub 0.5}Na{sub 0.5}TiO{sub 3}–xBi(Zn{sub 0.5}Hf{sub 0.5})O{sub 3} [(1???x)BNT–xBZH, x?=?0, 0.01, 0.02, 0.03, and 0.04] were investigated. The structure of Bi(Zn{sub 0.5}Hf{sub 0.5})O{sub 3} was calculated using first-principles method and (1???x)BNT–xBZH ceramics were fabricated by conventional solid-state process. At room temperature, a morphotropic phase boundary (MPB) from rhombohedral to pseudocubic is identified near x?=?0.02 by the analysis of X-ray diffraction patterns. The ceramics with MPB near room temperature exhibit excellent electrical properties: the Curie temperature, maximum polarization, remnant polarization, and coercive field are 340?°C, 56.3??C/cm{sup 2}, 43.5??C/cm{sup 2}, and 5.4?kV/mm, respectively, while the maximum positive bipolar strain and piezoelectric coefficient are 0.09% and 92 pC/N, respectively. In addition, a linear relationship between the MPB phase boundary composition and the calculated tetragonality of non-BNT end-member was demonstrated. Thus, this study not only shows a new BNT-based lead-free piezoelectric system but also suggest a new way to predict the composition at MPB a priori when designing new lead-free piezoelectric system.

  18. Process for reducing series resistance of solar-cell metal-contact systems with a soldering-flux etchant

    DOE Patents [OSTI]

    Coyle, R.T.; Barrett, J.M.

    1982-05-04

    Disclosed is a process for substantially reducing the series resistance of a solar cell having a thick film metal contact assembly thereon while simultaneously removing oxide coatings from the surface of the assembly prior to applying solder therewith. The process includes applying a flux to the contact assembly and heating the cell for a period of time sufficient to substantially remove the series resistance associated with the assembly by etching the assembly with the flux while simultaneously removing metal oxides from said surface of said assembly.

  19. Ames Lab 101: Technology Transfer

    ScienceCinema (OSTI)

    Covey, Debra

    2012-08-29

    Ames Laboratory Associate Laboratory Director, Sponsored Research Administration, Debra Covey discusses technology transfer. Covey also discusses Ames Laboratory's most successful transfer, lead-free solder.

  20. Mechanical Behavior of Indium Nanostructures

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

    Mechanical Behavior of Indium Nanostructures Print Indium is a key material in lead-free solder applications for microelectronics due to its excellent wetting properties, extended...

  1. Mechanical Behavior of Indium Nanostructures

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

    Mechanical Behavior of Indium Nanostructures Mechanical Behavior of Indium Nanostructures Print Wednesday, 26 May 2010 00:00 Indium is a key material in lead-free solder...

  2. Effect of composition on electrical properties of lead-free Bi{sub 0.5}(Na{sub 0.80}K{sub 0.20}){sub 0.5}TiO{sub 3}-(Ba{sub 0.98}Nd{sub 0.02})TiO{sub 3} piezoelectric ceramics

    SciTech Connect (OSTI)

    Jaita, Pharatree; Watcharapasorn, Anucha; Jiansirisomboon, Sukanda

    2013-07-14

    Lead-free piezoelectric ceramics with the composition of (1-x)Bi{sub 0.5}(Na{sub 0.80}K{sub 0.20}){sub 0.5}TiO{sub 3}-x(Ba{sub 0.98}Nd{sub 0.02})TiO{sub 3} or (1-x) BNKT-xBNdT (with x = 0-0.20 mol fraction) have been synthesized by a conventional mixed-oxide method. The compositional dependence of phase structure and electrical properties of the ceramics were systemically studied. The optimum sintering temperature of all BNKT-BNdT ceramics was found to be 1125 Degree-Sign C. X-ray diffraction pattern suggested that BNdT effectively diffused into BNKT lattice during sintering to form a solid solution with a perovskite structure. Scanning electron micrographs showed a slight reduction of grain size when BNdT was added. It was found that BNKT-0.10BNdT ceramic exhibited optimum electrical properties ({epsilon}{sub r} = 1716, tan{delta} = 0.0701, T{sub c} = 327 Degree-Sign C, and d{sub 33} = 211 pC/N), suggesting that this composition has a potential to be one of a promising lead-free piezoelectric candidate for dielectric and piezoelectric applications.

  3. Lead-free Thin Film Piezoelectric Devices - Energy Innovation Portal

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousand CubicResourcelogo and-E C H N I C A L TA L K <

  4. Misbehaving Mathematical Programs: Post Optimality Procedures and GAMS Related Software

    E-Print Network [OSTI]

    McCarl, Bruce A.

    included, relevant variables excluded or improperly entered variables in terms of coefficient signs implementation details(p. 238-40): a) search for bugs in the matrix; b) add constraints to force activities of measurement, calculation flaws, omissions, or improper placement; b) improper constraints in terms

  5. An analysis of the pull strength behaviors of fine-pitch, flip chip solder interconnections using a Au-Pt-Pd thick film conductor on Low-Temperature, Co-fired Ceramic (LTCC) substrates.

    SciTech Connect (OSTI)

    Uribe, Fernando R.; Kilgo, Alice C.; Grazier, John Mark; Vianco, Paul Thomas; Zender, Gary L.; Hlava, Paul Frank; Rejent, Jerome Andrew

    2008-09-01

    The assembly of the BDYE detector requires the attachment of sixteen silicon (Si) processor dice (eight on the top side; eight on the bottom side) onto a low-temperature, co-fired ceramic (LTCC) substrate using 63Sn-37Pb (wt.%, Sn-Pb) in a double-reflow soldering process (nitrogen). There are 132 solder joints per die. The bond pads were gold-platinum-palladium (71Au-26Pt-3Pd, wt.%) thick film layers fired onto the LTCC in a post-process sequence. The pull strength and failure modes provided the quality metrics for the Sn-Pb solder joints. Pull strengths were measured in both the as-fabricated condition and after exposure to thermal cycling (-55/125 C; 15 min hold times; 20 cycles). Extremely low pull strengths--referred to as the low pull strength phenomenon--were observed intermittently throughout the product build, resulting in added program costs, schedule delays, and a long-term reliability concern for the detector. There was no statistically significant correlation between the low pull strength phenomenon and (1) the LTCC 'sub-floor' lot; (2) grit blasting the LTCC surfaces prior to the post-process steps; (3) the post-process parameters; (4) the conductor pad height (thickness); (5) the dice soldering assembly sequence; or (5) the dice pull test sequence. Formation of an intermetallic compound (IMC)/LTCC interface caused by thick film consumption during either the soldering process or by solid-state IMC formation was not directly responsible for the low-strength phenomenon. Metallographic cross sections of solder joints from dice that exhibited the low pull strength behavior, revealed the presence of a reaction layer resulting from an interaction between Sn from the molten Sn-Pb and the glassy phase at the TKN/LTCC interface. The thick film porosity did not contribute, explicitly, to the occurrence of reaction layer. Rather, the process of printing the very thin conductor pads was too sensitive to minor thixotropic changes to ink, which resulted in inconsistent proportions of metal and glassy phase particles present during the subsequent firing process. The consequences were subtle, intermittent changes to the thick film microstructure that gave rise to the reaction layer and, thus, the low pull strength phenomenon. A mitigation strategy would be the use of physical vapor deposition (PVD) techniques to create thin film bond pads; this is multi-chip module, deposited (MCM-D) technology.

  6. THE LEAD AND COPPER RULE Anne Sandvig, HDR-EES

    E-Print Network [OSTI]

    Maynard, J. Barry

    THE LEAD AND COPPER RULE Anne Sandvig, HDR-EES 2008 Historical Background The 1986 Safe Drinking Water Act required the use of "lead-free" pipes, solders, pipe fittings or plumbing fixtures in the 1986 Amendment and were required to meet "voluntary standards." The term "lead-free" was defined

  7. High temperature ultrasonic gas flow sensor based on lead free piezoelectric material

    E-Print Network [OSTI]

    Krsmanovic, Dalibor

    2011-11-08

    ], and it is selected as the material of choice, having good abrasion resistance, desirable anti-corrosion properties and is cost effective for present application. This thesis begins with a broad literature review of current gas flow measurement technologies... are satisfied by flow meters with multiple ultrasonic measurement paths, typically supplied as a spool piece and used in custody transfer applications such as natural gas pipelines. With respect to flow metering in general, a substantial and key body of work...

  8. Thermodynamic and nonstoichiometric behavior of the lead-doped and lead-free Bi-2212 systems

    SciTech Connect (OSTI)

    Tetenbaum, M.; Hash, M.; Tani, B.S.; Luo, J.S.; Maroni, V.A.

    1997-02-01

    EMF measurements of oxygen fugacities as a function of stoichiometry were made on pb-doped and Pb-free superconducting ceramics at 700-815 C using oxygen titration. Equations of oxygen partial pressure vs composition and temperature were derived from the EMF measurements. Thermodynamic assessments of the partial molar quantities {Delta}{bar H}(O{sub 2}) and {Delta}{bar S}(O{sub 2}) for Pb-doped Bi- 2212 and Pb-free Bi-2212 indicate that the solid-state decomposition of these Bi cuprates at low oxygen partial pressure can be represented by the diphasic CuO-Cu{sub 2}O system. Comparison of these results with Pb-doped Bi-2223 in powder and silver sheath form is presented.

  9. Tailoring of unipolar strain in lead-free piezoelectrics using the ceramic/ceramic composite approach

    SciTech Connect (OSTI)

    Khansur, Neamul H.; Daniels, John E.; Groh, Claudia; Jo, Wook; Webber, Kyle G.; Reinhard, Christina; Kimpton, Justin A.

    2014-03-28

    The electric-field-induced strain response mechanism in a polycrystalline ceramic/ceramic composite of relaxor and ferroelectric materials has been studied using in situ high-energy x-ray diffraction. The addition of ferroelectric phase material in the relaxor matrix has produced a system where a small volume fraction behaves independently of the bulk under an applied electric field. Inter- and intra-grain models of the strain mechanism in the composite material consistent with the diffraction data have been proposed. The results show that such ceramic/ceramic composite microstructure has the potential for tailoring properties of future piezoelectric materials over a wider range than is possible in uniform compositions.

  10. PEREA: Practical TTP-Free Revocation of Repeatedly Misbehaving Anonymous Users

    E-Print Network [OSTI]

    Kapadia, Apu

    regimes, and activism. Fully anonymous access to services, however, can give users the license to misbe of such systems as an im- portant part of their roadmap,2 and in 2009 the PET award committee recognized our for the Award for Outsta

  11. PEREA: Practical TTP-Free Revocation of Repeatedly Misbehaving Anonymous Users

    E-Print Network [OSTI]

    Kapadia, Apu

    in oppressive regimes, and activism. Fully anonymous access to services, however, can give users the license of their roadmap,2 and in 2009 the PET award committee recognized our recent work for improving such systems.3 [35] and PEREA [36] were recognized as Runners up for the Award for Outstanding Research in Privacy

  12. MASTER OF SCIENCE MECHANICAL ENGINEERING

    E-Print Network [OSTI]

    , Lead Free Solder IMPROVED AEROTHERMODYNAMIC INSTRUMENTATION OF AN ALLISON T63-A-700 GAS TURBINE ENGINE for the gas generator turbine and exhaust state points were evaluated and average values were calculated. The gas generator turbine inlet and exhaust temperature profiles have been measured and show

  13. Relationship between morphologies and orientations of Cu{sub 6}Sn{sub 5} grains in Sn3.0Ag0.5Cu solder joints on different Cu pads

    SciTech Connect (OSTI)

    Tian, Yanhong, E-mail: tianyh@hit.edu.cn; Zhang, Rui; Hang, Chunjin; Niu, Lina; Wang, Chunqing

    2014-02-15

    The morphologies and orientations of Cu{sub 6}Sn{sub 5} intermetallic compounds in the Sn3.0Ag0.5Cu solder joints both on polycrystalline and single crystal Cu pads under different peak reflow temperatures and times above liquids were investigated. The relationship between Cu{sub 6}Sn{sub 5} grain orientations and morphologies was clarified. At the interface of Sn3.0Ag0.5Cu/polycrystalline Cu pad, scalloped Cu{sub 6}Sn{sub 5} intermetallic compounds formed at 250 °C and roof shape Cu{sub 6}Sn{sub 5} formed at 300 °C. Both scalloped Cu{sub 6}Sn{sub 5} and roof shape Cu{sub 6}Sn{sub 5} had a preferred orientation of (0001) plane being parallel to polycrystalline Cu pad surface. Besides, the percentage of large angle grain boundaries increased as the peak reflow temperature rose. At the interface of Sn3.0Ag0.5Cu/(111) single crystal Cu pad, the Cu{sub 6}Sn{sub 5} intermetallic compounds were mainly scallop-type at 250 °C and were prism type at 300 °C. The prismatic Cu{sub 6}Sn{sub 5} grains grew along the three preferred directions with the inter-angles of 60° on (111) single crystal Cu pad while along two perpendicular directions on (100) single crystal Cu pad. The orientation relationship between Cu{sub 6}Sn{sub 5} grains and the single crystal Cu pads was investigated by electron backscatter diffraction technology. In addition, two types of hollowed Cu{sub 6}Sn{sub 5} intermetallic compounds were found inside the joints of polycrystalline Cu pads. The long hexagonal Cu{sub 6}Sn{sub 5} strips were observed in the joints reflowing at 250 °C while the hollowed Cu{sub 6}Sn{sub 5} strips with the ‘?’ shape cross-sections appeared at 300 °C, which was attributed to the different grain growth rates of different Cu{sub 6}Sn{sub 5} crystal faces. - Highlights: • The orientation of interfacial Cu{sub 6}Sn{sub 5} grains was obtained by EBSD technology. • Two types of hollowed Cu{sub 6}Sn{sub 5} strips were found at different temperatures. • The formation mechanism of hollowed Cu{sub 6}Sn{sub 5} was elaborated based on Bravais law. • The relationship between Cu{sub 6}Sn{sub 5} grain orientations and morphologies was clarified.

  14. AWS breaks new ground with soldering specification.

    SciTech Connect (OSTI)

    Vianco, Paul Thomas

    2008-08-01

    Joining technologies continue to advance with new materials, process innovations, and inspection techniques. An increasing number of high-valued, high-reliability applications -- from boilers and ship hulls to rocket motors and medical devices -- have required the development of industry standards and specifications in order to ensure that the best design and manufacturing practices are being used to produce safe, durable products and assemblies. Standards writing has always had an important role at the American Welding Society (AWS). The AWS standards and specifications cover such topics as filler materials, joining processes, inspection techniques, and qualification methods that are used in welding and brazing technologies. These AWS standards and specifications, all of which are approved by the American National Standards Institute (ANSI), have also provided the basis for many similar documents used in Europe and in Pacific Rim countries.

  15. Environ.Sci.Technol.1982,76. 23-30 !5V9 of the gasolineused was lead free; in 1980,the un-

    E-Print Network [OSTI]

    Short, Daniel

    .;Skogerboe,R.K.Enuiron.Sci.Technol.1978, 9,227-3r. (11) Instituto -Nacional rl,F Sismologia,Vulcanologia, Meteorologia,e Hidrologia

  16. Electro-caloric effect in lead-free Sn doped BaTiO{sub 3} ceramics at room temperature and low applied fields

    SciTech Connect (OSTI)

    Upadhyay, Sanjay Kumar; Reddy, V. Raghavendra E-mail: vrreddy@csr.res.in; Bag, Pallab; Rawat, R.; Gupta, S. M.; Gupta, Ajay

    2014-09-15

    Structural, dielectric, ferroelectric (FE), {sup 119}Sn Mössbauer, and specific heat measurements of polycrystalline BaTi{sub 1–x}Sn{sub x}O{sub 3} (x?=?0% to 15%) ceramics are reported. Phase purity and homogeneous phase formation with Sn doping is confirmed from x-ray diffraction and {sup 119}Sn Mössbauer measurements. With Sn doping, the microstructure is found to change significantly. Better ferroelectric properties at room temperature, i.e., increased remnant polarization (38% more) and very low field switchability (225% less) are observed for x?=?5% sample as compared to other samples and the results are explained in terms of grain size effects. With Sn doping, merging of all the phase transitions into a single one is observed for x???10% and for x?=?5%, the tetragonal to orthorhombic transition temperature is found close to room temperature. As a consequence better electro-caloric effects are observed for x?=?5% sample and therefore is expected to satisfy the requirements for non-toxic, low energy (field) and room temperature based applications.

  17. ULTRAFAST RADIATION HEAT TRANSFER IN LASER TISSUE WELDING AND SOLDERING

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    , respectively. 1. INTRODUCTION The study of short-pulsed laser radiation transport and ultrafast matter­ radiation interactions is of great scientific and technological significance and is attracting increasing­9], to name a few. Due to the very short time duration of the radia- tion­matter interaction and transport

  18. Solder Joints of Power Electronics | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURINGEnergy BillsNo.Hydrogen4Energy SmoothEquipmentSolar PVEquipment Salesof201110

  19. Solder Joints of Power Electronics | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURINGEnergy BillsNo.Hydrogen4Energy SmoothEquipmentSolar PVEquipment Salesof20111009

  20. The integration of laser diode arrays into bondable solder-grid-arrays C. Gimkiewicz, D. Hagedorn

    E-Print Network [OSTI]

    Jahns, Jürgen

    coatings IC chips thermal via ;;;; Fig. 1: A multichip module with buried vertical-cavity surface intra-cavity contact is flipchip bonded to electroplated donut shaped rings, fig. 1(b), which serve

  1. Evaluation of optical solder for fiber-to-waveguide coupling in silicon photonics

    E-Print Network [OSTI]

    Tjioe, Fidelia

    2008-01-01

    Copper interconnects have shown its limit to meet the bandwidth demand even in the short reach applications due to its increase power consumption, RC delay, EMI, crosstalk and other effects which are aggravated as dimension ...

  2. Impacts of Cooling Technology on Solder Fatigue for Power Modules in Electric Traction Drive Vehicles: Preprint

    SciTech Connect (OSTI)

    O'Keefe, M.; Vlahinos, A.

    2009-08-01

    Describes three power module cooling topologies for electric traction drive vehicles: two advanced options using jet impingement cooling and one option using pin-fin liquid cooling.

  3. Structure and kinetics of Sn whisker growth on Pb-free solder finish

    E-Print Network [OSTI]

    2002-01-01

    especially the eutectic SnCu, a large number of Sn whiskersroom temperature on eutectic SnCu and pure Sn finishes. Bothfinish is typically eutectic SnCu or pure Sn. On the SnCu

  4. Influence of the Substrate on the Creep of SN Solder Joints

    E-Print Network [OSTI]

    Lee, K.-O.; Morris, J.W.; Hua, F.

    2010-01-01

    under nitrogen gas. The creep tests were done in a dead-loadhere. Details of the creep test procedure have been reportednor fractured during the creep tests done here, the chemical

  5. Photovoltaic effect of lead-free (Na{sub 0.82}K{sub 0.18}){sub 0.5}Bi{sub 4.5}Ti{sub 4}O{sub 15} ferroelectric thin film using Pt and indium tin oxide top electrodes

    SciTech Connect (OSTI)

    Seok Woo, Won; Sik Won, Sung; Won Ahn, Chang; Chae, Song A; Won Kim, Ill, E-mail: kimiw@mail.ulsan.ac.kr [Department of Physics and Energy Harvest-Storage Research Center (EHSRC), University of Ulsan, Ulsan 680-749 (Korea, Republic of); Ullah, Aman [Department of Physics, University of Science and Technology, Bannu, Khyber Pakhtunkhwa (Pakistan)

    2014-01-21

    We have grown a Bi-layer structure (Na{sub 0.82}K{sub 0.18}){sub 0.5}Bi{sub 4.5}Ti{sub 4}O{sub 15} (NKBiT) ferroelectric thin film on Pt(111)/TiO{sub 2}/SiO{sub 2}/Si(100) substrate by using the chemical solution deposition method and deposited two kinds of thin Pt and indium tin oxide (ITO) top electrodes. The photovoltaic behaviors of Pt/NKBiT/Pt and ITO/NKBit/Pt capacitors were investigated over the wavelength range of 300–500?nm. When NKBiT thin film is illuminated by the corresponding wavelength of the film's energy band gap (E{sub g}), a photocurrent is generated due to the Schottky barrier between electrode and film, and an internal electric field is originated by the depolarization field. The maximum photocurrent density and power conversion efficiency of the ITO/NKBiT/Pt capacitor in the poled-up state are obtained as 45.75?nA/cm{sup 2} and 0.035%, respectively, at 352?nm. The photocurrent density and power conversion efficiency of the ITO/NKBiT/Pt capacitor increased to 3.5 times higher than that of the Pt/NKBiT/Pt capacitor.

  6. Temperature driven nano-domain evolution in lead-free Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}-50(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} piezoceramics

    SciTech Connect (OSTI)

    Lu, Shengbo Xu, Zhengkui; Su, Shi; Zuo, Ruzhong

    2014-07-21

    Hierarchical micro- and nanoscale domain structures in Pb-free Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}-50(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} piezoceramics were investigated by transmission electron microscopy. In situ heating and cooling studies of domain structure evolution reveal an irreversible domain transformation from a wedge-shaped rhombohedral nanodomain structure to a lamellar tetragonal domain structure, which could be associated with strong piezoelectricity in Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}-50(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} piezoceramics.

  7. Aging Effects on the Microstructure, Surface Characteristics and Wettability of Cu Pretinned with Sn-Pb Solders

    E-Print Network [OSTI]

    Linch, H.S.

    2010-01-01

    substrates using electroplating or hot dipping techniques.were applied using electroplating or hot dipping techniques.rich hot- dipped. Electroplating procedures and guidelines

  8. Growth of a Au-Ni-Sn intermetallic compound on the solder-substrate interface after aging (thesis)

    E-Print Network [OSTI]

    Minor, A.M.

    2011-01-01

    of Eutectic Sn/Pb”, M.S. Thesis, U.C. Berkeley, (May 1992) IAndrew Murphy Minor M.S. Thesis Department of Materialsmy research on this thesis. Additionally, I am indebted to

  9. Micro-Columnated Loop Heat Pipe: The Future of Electronic Substrates

    E-Print Network [OSTI]

    Dhillon, Navdeep Singh

    2012-01-01

    ?LHP 2-phase flow water leakage Valves (b) Heated Flask (a)inch-OD Valves Solder connection Fluid leakage at solder

  10. Multiwire conductor having increased interwire resistance and good mechanical stability and method for making same

    DOE Patents [OSTI]

    Luhman, T.; Klamut, C.

    1982-03-15

    An improved multiwire conductor of the type which is mechanically stabilized by a solder filler. A solder filled conductor is heated to a temperature sufficient to make the solder brittle, but below the melting point of the solder. While still hot, the conductor is flexed, causing the solder to separate from the wires comprising the conductor, thereby increasing the interwire resistance. In one embodiment the conductor may be heated to a temperature above the eutectic temperature of the solder so that a controlled amount of solder is removed. The subject invention is particularly suited for use with braided, ribbon-type, solder filled superconductors.

  11. Cleaning process development and optimization in the surface mount assembly line of power modules

    E-Print Network [OSTI]

    Mukherjee, Ishan

    2011-01-01

    The cleaning process in the surface mount assembly line of power modules had been found to insufficiently remove solder flux residue from printed circuit board (PCB) assemblies after the process of reflow soldering. This ...

  12. TM-mode coupling to a Josephson junction S. J. Lewandowski

    E-Print Network [OSTI]

    Boyer, Edmond

    of the junction electrodes. to the j unction was provided by two leads immersed in superconducting solder, which

  13. UNIVERSITY OF MINNESOTA SCHOOL OF PHYSICS AND ASTRONOMY STUDENT SHOP HANDBOOK

    E-Print Network [OSTI]

    Dahlberg, E. Dan

    Vertical Milling Machine Safety Rules Page 7 Lathe Safety Rules Page 8 Soldering Safety Rules Page 9

  14. Electronic Parts and Services Parts: Engineering East (EE), Room 205, open 9 a.m. -5 p.m., Monday through Friday

    E-Print Network [OSTI]

    Fernandez, Eduardo

    -Static Current High Voltage Probes, Probes Drills and Chargers Gold Pins Cables Velcro Tape, Tie Wraps Soldering

  15. Multiwire conductor having greatly increased interwire resistance and method for making same

    DOE Patents [OSTI]

    Luhman, T.; Suenaga, M.

    1982-03-15

    An improved multiwire conductor of the type which is mechanically stabilized by a tin based solder filler is described. A solder filled conductor is heated to a temperature above its melting point for a period long enough to allow a substantial amount of copper to be dissolved from the wires comprising the conductor. The copper forms the brittle intermetallic compound Cu/sub 5/Sn/sub 6/ with tin in the solder. After cooling the conductor is flexed causing a random cracking of the solder, and thereby increasing the interwire resistance of the conductor. The subject invention is particularly adapted for use with braided, ribbon-type solder filled superconductors.

  16. Removal of aqueous rinsable flux residues in a batch spray dishwater

    SciTech Connect (OSTI)

    Slanina, J.T.

    1992-02-01

    An alkaline detergent solution used in an industrial dishwasher was evaluated to remove aqueous rinsable flux residues on printed wiring boards (PWBs) after hot air solder leveling and hot oil solder dip and leveling. The dishwasher, a batch cleaning process, was compared to an existing conveyorized aqueous cleaning process. The aqueous soluble flux residues from both soldering processes were removed with a solution of a mild alkaline detergent dissolved in hot deionized (DI) water.

  17. Review of Direct Metal Bonding for Microelectronic Interconnections

    E-Print Network [OSTI]

    Zhang, G.G.

    Microelectronic interconnections require advanced joining techniques. Direct metal bonding methods, which include thercomsonic and thermocompression bonding, offer remarkable advantages over soldering and adhesives joining. ...

  18. Materials Science and Engineering A 458 (2007) 101107 Fluxless silicon-to-alumina bonding using electroplated

    E-Print Network [OSTI]

    Chen, Zhongping

    2007-01-01

    electroplated Au­Sn­Au structure at eutectic composition Jong S. Kima, Won S. Choia,1, Dongwook Kima,2, Andrei successfully bonded to alumina substrates with electroplated Au/Sn/Au structure at the eutectic composition. Keywords: Fluxless bonding; Fluxless soldering; Soldering; Eutectic Au­Sn alloys; Electroplating 1

  19. 12/31/11 Analog to Digital Converter Test Report Page 1 of 5 Created 3/3/08 by Nicole Rodia Modified 5/18/08 11:01 PM by Nicole Rodia

    E-Print Network [OSTI]

    Ruina, Andy L.

    as well as on the Ko Brain board under a variety of conditions. Using the Ko Brain board, tests were wire Soldering iron 1.5 V battery Battery holder 10 k, 100 k resistors 22 nF capacitor Multimeter wrap wire to keep wires short to reduce electromagnetic interference. Soldered connections to battery

  20. Method for optical and mechanically coupling optical fibers

    DOE Patents [OSTI]

    Toeppen, John S. (Livermore, CA)

    1996-01-01

    A method and apparatus for splicing optical fibers. A fluorescing solder glass frit having a melting point lower than the melting point of first and second optical fibers is prepared. The solder glass frit is then attached to the end of the first optical fiber and/or the end of the second optical fiber. The ends of the optical fibers are aligned and placed in close proximity to each other. The solder glass frit is then heated to a temperature which is lower than the melting temperature of the first and second optical fibers, but which is high enough to melt the solder glass frit. A force is applied to the first and second optical fibers pushing the ends of the fibers towards each other. As the solder glass flit becomes molten, the layer of molten solder glass is compressed into a thin layer between the first and second optical fibers. The thin compressed layer of molten solder glass is allowed to cool such that the first and second optical fibers are bonded to each other by the hardened layer of solder glass.

  1. Journal of Electronic Materials ISSN 0361-5235

    E-Print Network [OSTI]

    Chung, Deborah D.L.

    -offprint is for personal use only and shall not be self- archived in electronic repositories. If you wish to self, are excellent thermal interface materials (TIMs). Solders 63Sn-37Pb and 95.5Sn-4Ag-0.5Cu are separately used conductance exceeds or is comparable to that of all other TIMs, provided that solder reflow has occurred

  2. California Households’ Willingness to Pay for “Green” Electronics

    E-Print Network [OSTI]

    Saphores, Jean-Daniel M; Nixon, Hilary; Ogunseitan, Oladele; Shapiro, Andrew A

    2007-01-01

    Adults Towards Consumer Electronics Chicago, IL. Montgomery,2005. Adopting lead-free electronics: Knowledge gaps andworth taking Consumer Electronics Association, Arlington,

  3. School Composition and Disproportionality in Discipline: A School-Level Analysis of Disciplinary Actions against Various Offense Types in the United States, 2007-2008

    E-Print Network [OSTI]

    Fisher, Julie Diane

    2011-04-11

    in his truck, presumably to go hunting after school, to turn his truck around and take his gun home without any disciplinary punishment. Rural administrators were more likely to overlook this violation as long as the weapon was in the student’s vehicle..., placing them in in-school suspension is an easy alternative so teachers do not have to deal with misbehaving students. In the late 1980s and early 1990s schools began to experience more violence such as guns, drugs, and gangs. In response...

  4. Low temperature transient liquid phase bonding of copper

    E-Print Network [OSTI]

    Williams, Joel C. (Joel Carlton)

    2005-01-01

    This thesis describes a Pb-free solder alternative that is capable of fluxless bonding. The main advantage of this process is that it offers the benefits of low fabrication temperature (125?C) while producing a joint capable ...

  5. IEEE TRANSACTIONS ON ADVANCED PACKAGING, VOL. 30, NO. 3, AUGUST 2007 551 Experimental Analysis of the Water Absorption

    E-Print Network [OSTI]

    Tentzeris, Manos

    by the National Aeronautics and Space Administration under Contract NCC3-1015, by the National Science Foundation consisting of several integrated circuits (ICs) with plastic injection molded packages, which are soldered

  6. Use of a Direct Search Algorithm in the Process Design of Material ...

    E-Print Network [OSTI]

    Le Digabel

    2014-12-02

    Dec 2, 2014 ... for hundreds of metallic, oxide, and salt solutions (solid and liquid). ...... design of new free-lead solders alloys or for the design of new cast ...

  7. Low-temperature hermetic sealing of optical fiber components

    SciTech Connect (OSTI)

    Kramer, D.P.

    1995-12-31

    A method for manufacturing low-temperature hermetically sealed optical fiber components is provided. The method comprises the steps of: inserting an optical fiber into a housing, the optical fiber having a glass core, a glass cladding and a protective buffer layer disposed around the core and cladding; heating the housing to a predetermined temperature, the predetermined temperature being below a melting point for the protective buffer layer and above a melting point of a solder; placing the solder in communication with the heated housing to allow the solder to form an eutectic and thereby fill a gap between the interior of the housing and the optical fiber; and cooling the housing to allow the solder to form a hermetic compression seal between the housing and the optical fiber.

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

    DOE Patents [OSTI]

    Rao, Triveni; Walsh, John; 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.

  9. 2004 American Chemical Society JANUARY 1, 2004 / ENVIRONMENTAL SCIENCE & TECHNOLOGY 19A J A M E S A . R Y A N

    E-Print Network [OSTI]

    Brown, Sally

    - rent reduction of lead in automotive emissions, paint, drinking water, and soldered food cans (3). Yet, and groundwaters. Flaking paint, decades of leaded gasoline use, min- ing operations, smelter and industrial

  10. OutboardInboard OutboardInboard

    E-Print Network [OSTI]

    California at Los Angeles, University of

    cutting, ink jet printers, continuous rod/sheet/ribbon/sphere casting, flood/jet soldering, ocean waves growth, astrophysical phenomena, liquid metal walls for particle accelerators and fusion reactors · Liquid MHD / turbulence interactions: microstructure control in casting, boundary layer control

  11. Journal of Manufacturing Processes Vol. 6/No. 1

    E-Print Network [OSTI]

    Kharoufeh, Jeffrey P.

    of Multiple-Joint Solder Self-Assembled Microelectromechanical Systems (MEMS) Paul E. Kladitis, Air Force, USA Abstract Surface-micromachined microelectromechanical systems (MEMS) are two dimensional, Tolerance Analysis Introduction Microelectromechanical systems (MEMS) fabri- cation can be generally

  12. XINGHUI LIU 1111 Engineering Drive, UCB 427, Boulder, Colorado 80309-0427

    E-Print Network [OSTI]

    Bunch, Scott

    : machining, mold & die, 3D printing, PCB, soldering and etc. (~2 years hands-on experience) Programming atomization system to produce an ultra-fine metal powers. ---- NSF in China 3D printing with laser sintering

  13. Low-temperature hermetic sealing of optical fiber components

    DOE Patents [OSTI]

    Kramer, Daniel P. (Centerville, OH)

    1996-10-22

    A method for manufacturing low-temperature hermetically sealed optical fi components is provided. The method comprises the steps of: inserting an optical fiber into a housing, the optical fiber having a glass core, a glass cladding and a protective buffer layer disposed around the core and cladding; heating the housing to a predetermined temperature, the predetermined temperature being below a melting point for the protective buffer layer and above a melting point of a solder; placing the solder in communication with the heated housing to allow the solder to form an eutectic and thereby fill a gap between the interior of the housing and the optical fiber; and cooling the housing to allow the solder to form a hermetic compression seal between the housing and the optical fiber.

  14. Low-temperature hermetic sealing of optical fiber components

    DOE Patents [OSTI]

    Kramer, D.P.

    1996-10-22

    A method for manufacturing low-temperature hermetically sealed optical fiber components is provided. The method comprises the steps of: inserting an optical fiber into a housing, the optical fiber having a glass core, a glass cladding and a protective buffer layer disposed around the core and cladding; heating the housing to a predetermined temperature, the predetermined temperature being below a melting point for the protective buffer layer and above a melting point of a solder; placing the solder in communication with the heated housing to allow the solder to form an eutectic and thereby fill a gap between the interior of the housing and the optical fiber; and cooling the housing to allow the solder to form a hermetic compression seal between the housing and the optical fiber. 5 figs.

  15. STUDY OF THE RHIC BPM SMA CONNECTOR FAILURE PROBLEM

    SciTech Connect (OSTI)

    LIAW,C.; SIKORA, R.; SCHROEDER, R.

    2007-06-25

    About 730 BPMs are mounted on the RHIC CQS and Triplet super-conducting magnets. Semi-rigid coaxial cables are used to bring the electrical signal from the BPM feedthroughs to the outside flanges. at the ambient temperature. Every year around 10 cables will lose their signals during the operation. The connection usually failed at the warm end of the cable. The problems were either the solder joint failed or the center conductor retracted out of the SMA connector. Finite element analyses were performed to understand the failure mechanism of the solder joint. The results showed that (1) The SMA center conductor can separate from the mating connector due to the thermal retraction. (2) The maximum thermal stress at the warm end solder joint can exceed the material strength of the Pb37/Sn63 solder material and (3) The magnet ramping frequency (-10 Hz), during the machine startup, can possibly resonant the coaxial cable and damage the solder joints, especially when a fracture is initiated. Test results confirmed that by using the silver bearing solder material (a higher strength material) and by crimping the cable at the locations close to the SMA connector (to prevent the center conductor from retracting) can effectively resolve the connector failure problem.

  16. Effect of Alloying Element on the Structure of Cu-Zn Alloy

    Office of Scientific and Technical Information (OSTI)

    mold casting of copper-base alloys, including grain refinement as part of developing new lead-free copper alloys for plumbing applications, is being carried out at Materials...

  17. Ceramic-polymer nanocomposites with increased dielectric permittivity and low dielectric loss

    SciTech Connect (OSTI)

    Bhardwaj, Sumit Paul, Joginder; Raina, K. K.; Thakur, N. S.; Kumar, Ravi

    2014-04-24

    The use of lead free materials in device fabrication is very essential from environmental point of view. We have synthesized the lead free ferroelectric polymer nanocomposite films with increased dielectric properties. Lead free bismuth titanate has been used as active ceramic nanofillers having crystallite size 24nm and PVDF as the polymer matrix. Ferroelectric ?-phase of the polymer composite films was confirmed by X-ray diffraction pattern. Mapping data confirms the homogeneous dispersion of ceramic particles into the polymer matrix. Frequency dependent dielectric constant increases up to 43.4 at 100Hz, whereas dielectric loss decreases with 7 wt% bismuth titanate loading. This high dielectric constant lead free ferroelectric polymer films can be used for energy density applications.

  18. Modeling tin whisker growth.

    SciTech Connect (OSTI)

    Weinberger, Christopher Robert

    2013-08-01

    Tin, lead, and lead-tin solders are the most commonly used solders due to their low melting temperatures. However, due to the toxicity problems, lead must now be removed from solder materials. This has lead to the re-emergence of the issue of tin whisker growth. Tin whiskers are a microelectronic packaging issue because they can lead to shorts if they grow to sufficient length. However, the cause of tin whisker growth is still not well understood and there is lack of robust methods to determine when and if whiskering will be a problem. This report summarizes some of the leading theories on whisker growth and attempts to provide some ideas towards establishing the role microstructure plays in whisker growth.

  19. Solar cell array interconnects

    DOE Patents [OSTI]

    Carey, P.G.; Thompson, J.B.; Colella, N.J.; Williams, K.A.

    1995-11-14

    Electrical interconnects are disclosed for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value. 4 figs.

  20. Solar cell array interconnects

    DOE Patents [OSTI]

    Carey, Paul G. (Mountain View, CA); Thompson, Jesse B. (Brentwood, CA); Colella, Nicolas J. (Livermore, CA); Williams, Kenneth A. (Livermore, CA)

    1995-01-01

    Electrical interconnects for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value.

  1. Process for electrically interconnecting electrodes

    DOE Patents [OSTI]

    Carey, Paul G. (Mountain View, CA); Thompson, Jesse B. (Brentwood, CA); Colella, Nicolas J. (Livermore, CA); Williams, Kenneth A. (Livermore, CA)

    2002-01-01

    Electrical interconnects for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb--Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb--Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value.

  2. Method of assembling an electric power

    DOE Patents [OSTI]

    Rinehart, Lawrence E. (Lake Oswego, OR); Romero, Guillermo L. (Phoenix, AZ)

    2007-05-03

    A method of assembling and providing an electric power apparatus. The method uses a heat resistant housing having a structure adapted to accommodate and retain a power circuit card and also including a bracket adapted to accommodate and constrain a rigid conductive member. A power circuit card having an electrical terminal is placed into the housing and a rigid conductive member into the bracket. The rigid conductive member is flow soldered to the electrical terminal, thereby exposing the heat resistant housing to heat and creating a solder bond. Finally, the rigid conductive member is affirmatively connected to the housing. The bracket constrains the rigid conductive member so that the act of affirmatively connecting does not weaken the solder bond.

  3. Evaluation of Heat Checking and Washout of Heat Resistant Superalloys and Coatings for Die inserts

    SciTech Connect (OSTI)

    David Schwam; John F. Wallace; Yulong Zhu; Edward Courtright; Harold Adkins

    2005-01-30

    This project had two main objectives: (1) To design, fabricate and run a full size test for evaluating soldering and washout in die insert materials. This test utilizes the unique capabilities of the 350 Ton Squeeze Casting machine available in the Case Meal Casting Laboratory. Apply the test to evaluate resistance of die materials and coating, including heat resistant alloys to soldering and washout damage. (2) To evaluate materials and coatings, including heat resistant superalloys, for use as inserts in die casting of aluminum alloys.

  4. Development of Readout Interconnections for the Si-W Calorimeter of SiD

    SciTech Connect (OSTI)

    Woods, M.; Fields, R.G.; Holbrook, B.; Lander, R.L.; Moskaleva, A.; Neher, C.; Pasner, J.; Tripathi, M.; /UC, Davis; Brau, J.E.; Frey, R.E.; Strom, D.; /Oregon U.; Breidenbach, M.; Freytag, D.; Haller, G.; Herbst, R.; Nelson, T.; /SLAC; Schier, S.; Schumm, B.; /UC, Santa Cruz

    2012-09-14

    The SiD collaboration is developing a Si-W sampling electromagnetic calorimeter, with anticipated application for the International Linear Collider. Assembling the modules for such a detector will involve special bonding technologies for the interconnections, especially for attaching a silicon detector wafer to a flex cable readout bus. We review the interconnect technologies involved, including oxidation removal processes, pad surface preparation, solder ball selection and placement, and bond quality assurance. Our results show that solder ball bonding is a promising technique for the Si-W ECAL, and unresolved issues are being addressed.

  5. Technique for Measuring Hybrid Electronic Component Reliability

    SciTech Connect (OSTI)

    Green, C.C.; Hernandez, C.L.; Hosking, F.M.; Robinson, D.; Rutherford, B.; Uribe, F.

    1999-01-01

    Materials compatibility studies of aged, engineered materials and hardware are critical to understanding and predicting component reliability, particularly for systems with extended stockpile life requirements. Nondestructive testing capabilities for component reliability would significantly enhance lifetime predictions. For example, if the detection of crack propagation through a solder joint can be demonstrated, this technique could be used to develop baseline information to statistically determine solder joint lifelengths. This report will investigate high frequency signal response techniques for nondestructively evaluating the electrical behavior of thick film hybrid transmission lines.

  6. A radiation-hardened, low-noise, high-speed, integrated charge preamplifier for the Superconducting Supercollider 

    E-Print Network [OSTI]

    Ling, Kuok Young

    1989-01-01

    of the tester enclosed in an Aluminium box, 28 HP6062A Pulse 6enerator 50 0 coax +7 V Ferrite Bead 10 pF Chip 1 pF 1 ns 47 0 61FE Pream Ibias N4416 475 0 1 mH g Ferrite 6ead -7 V 50 0 coax HP541110 Wavet. Rec. Fig. 13. Complete test set... and all the circuit components are soldered onto the PCB. A 24-pin. text tool socket is also soldered onto the PCB to make repetition of measurements easy to manage. The PCB is then mounted onto the Aluminium box by using four plastic snap-on's. A test...

  7. Determination of rate constants for the reaction between methyldiethanolamine and carbon dioxide 

    E-Print Network [OSTI]

    Brabson, Charles Meade

    1985-01-01

    a Nz atmosphere in the drums and also to agitate the amine solution. The feed pump was a Teel model 1P988 rated at 3 gpm (11. 5 lit/min) at 500 psia (35 atm). It was constructed of cast iron. The QS Sample Port QT Thermocouple 6 Pressure Gauge..., no welding or soldering was required which may have damaged the disc. A stainless steel plate was then welded onto the bottom of the reactor. This created a boxed enclosure. The feed gas entered this enclosure through 1/4" stainless steel tubing soldered...

  8. Double-sided polyimide printed wiring boards. Final report

    SciTech Connect (OSTI)

    Lula, J.W.

    1982-04-01

    Double-sided polyimide/glass printed wiring boards (PWBs) were evaluated for high temperature performance and compared to epoxy/glass PWBs (type GH). Test specimens, as well as sample PWBs, were manufactured from both materials and tested for thermal stability, moisture absorption, copper peel strength, and resistance to soldering damage. Although the polyimide laminate absorbed more than twice the amount of moisture as the epoxy laminate, the polyimide laminate had greater thermal stability, retained greater peel strength at elevated temperatures, and showed comparatively little damage during soldering processes.

  9. Lead Safety Awareness This Bulletin provides information on the safe handling of lead

    E-Print Network [OSTI]

    Lead Safety Awareness PURPOSE This Bulletin provides information on the safe handling of lead and lead compounds during use and storage. Improper handling of lead and lead compounds may impact operations at Department of Energy (DOE) facilities. BACKGROUND Lead is found in batteries, pipes, solder

  10. EU PVSEC, 4AV.3.8 A MODELING APPROACH TO THE OPTIMIZATION OF INTERCONNECTS FOR BACK CONTACT CELLS

    E-Print Network [OSTI]

    down to -40°C. In a second step we add the interconnectors in a 2-dimensional geometry which the 3 soldered areas to depend significantly on the specific interconnector design. The model presented plain-stress modeling of the interconnector allows fast and easy modifications of the interconnector

  11. ME 354, MECHANICS OF MATERIALS LAB February 2009 NJS

    E-Print Network [OSTI]

    Sniadecki, Nathan J.

    , you MUST wash your hands with soap and water immediately after the lab. 1) Cut four lengths of solder) Install the top end of the specimen in the top grip of the creep test and lightly tighten the wing-nut. 5) Install the bottom end of the specimen in the lower grip and lightly tighten the wing-nut. You will need

  12. ME 354, MECHANICS OF MATERIALS LAB February 2010 NJS

    E-Print Network [OSTI]

    Sniadecki, Nathan J.

    , you MUST wash your hands with soap and water immediately after the lab. 1) Cut four lengths of solder) Install the top end of the specimen in the top grip of the creep test and lightly tighten the wing-nut. 5) Install the bottom end of the specimen in the lower grip and lightly tighten the wing-nut. You will need

  13. Optical Inspection of Welding Seams Fabian Timm1,2

    E-Print Network [OSTI]

    Optical Inspection of Welding Seams Fabian Timm1,2 , Thomas Martinetz1 , and Erhardt Barth1,2 1 present a framework for automatic inspection of welding seams based on specular reflections. To this end by using welding techniques. Soldering and welding techniques are common in diverse areas such as printed

  14. CRYOGENIC SYSTEM FOR CONTINUOUS ULTRAHIGH HYDROGEN PURIFICATION IN CIRCULATION MODE

    E-Print Network [OSTI]

    Kammel, Peter

    heaters (H1-3) are wound between the heat exchanger's turns. Temperature sensors (PT-100 type) are fixed such cartridges (on the scheme ­ C1-3). Every column is equipped by a spiral copper pipe ­ heat exchanger for liquid nitrogen. Heat exchanger is fixed on the compressor by a solid solder. Coils of the electrical

  15. NISTIR 5732 Calorimetric and Visual Measurements of R123

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    ) High-FluxTM , (3) GEWA-KTM , and (4) GEWA-TTM. The surfaces were either machined or soldered onto of nucleate boiling were also investigated. The boiling was visually recorded with 16 mm high speed film, enhanced heat transfer, porous surface, T-fin, trapezoidal-fin, R123, pool boiling, Turbo-BITM, High

  16. SPATIAL AND DIRECTIONAL DISTRIBUTION OF CRACKS IN SILICON PV MODULES AFTER UNIFORM MECHANICAL LOADS

    E-Print Network [OSTI]

    Sarah Kajari-Schröder, Iris Kunze, Ulrich Eitner and Marc Köntges Institute for Solar Energy Research photovoltaic modules are subjected to a variety of mechanical loads. During the manufacturing of the module, materials with different thermal expansion coefficients are bonded (e.g. soldering, lamination). This leads

  17. e-mail: rahman@engineering.uiowa.edu Department of Mechanical & Industrial

    E-Print Network [OSTI]

    Rahman, Sharif

    subject to cyclic thermal loading. It involves a global deformation analysis, a local critical solder analysis, the total fatigue life predicted using the energy-based method is larger than 2500 cycles revalida- tion when changes occur in the design or manufacturing pro- cesses. In addition, currently

  18. Caroline S. Lee Graduate Student,

    E-Print Network [OSTI]

    Eagar, Thomas W.

    and Rymaszewski, 1989, pp. 1151-1154). This study focuses on C4 solder bumps to understand the Pb/Sn surface layer of pitch separation require- ments between bumps and the self-aligning property of C4 die attach (Tummala typically consists of a proprie- tary mix of reactive and refractory metals, were studied. Specifically, C4

  19. Building Adaptable Sensor Networks with Sensor Cubes

    E-Print Network [OSTI]

    Roussos, George

    (battery voltage, charge/discharge current, input power, ...) Wireless link: · To nearby sensor modules of autonomous wireless sensor module Alternative hardware implementation using solder ball interconnect technology Wireless sensor module on 2 EUR coin Sensor module hardware Wide application range requires

  20. Energy Procedia 27 (2012) 658 663 1876-6102 2012 Published by Elsevier Ltd.Selection and/or peer review under responsibility of the Centro de Micro Anlisis de Materiales,

    E-Print Network [OSTI]

    2012-01-01

    of cracks in PV modules S. Kajari-Schrödera *, I. Kunzea , M. Köntgesa a Institute for Solar Energy Research of the module lifetime: during manufacturing in particular the soldering induces high stresses into the solarEnergy Procedia 27 (2012) 658 ­ 663 1876-6102 © 2012 Published by Elsevier Ltd.Selection and

  1. Semiconductor Components Industries, LLC, 2004 July, 2004 -Rev. 13

    E-Print Network [OSTI]

    Ravikumar, B.

    download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. PDIP-14 N, P Power Dissipation @ TA = 25°C Plastic Package Derate above 25°C PD 1/RqJA 1.0 8.0 W mW/°C Junction

  2. INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF MICROMECHANICS AND MICROENGINEERING J. Micromech. Microeng. 16 (2006) S198S205 doi:10.1088/0960-1317/16/9/S05

    E-Print Network [OSTI]

    Tokyo, University of

    2006-01-01

    . Combustion experiments were carried out in a solder bath to keep the catalyst temperature constant. Complete MW m-3 heat generation. Reaction constants for catalytic combustion on the Pd/nano-porous alumina such as methanol, propane and butane is tens of times larger than that of the Li-ion battery. Therefore

  3. Proceedings of FEDSM99 3rd ASME/JSME Joint Fluids Engineering Conference

    E-Print Network [OSTI]

    Sussman, Mark

    .5 nanoliters at rates of up to 4,000 drops per second. In addition to ink- jet printing, applications include dispensing solder in mi- croelectronics manufacturing processes (Bernardini et al., 1991), biomedical procedures and equipment (e.g., dye- assisted laser surgery), medical diagnostics manufacturing (e

  4. "control-Alt-Delete": Rebooting Solutions for the E-Waste Problem

    E-Print Network [OSTI]

    Li, J; Zeng, X; Chen, M; Ogunseitan, OA; Stevels, A

    2015-01-01

    waste. Clean: Soil, Air, Water 2008, 36 (1), 19?24. (83) Li,soldering. Clean: Soil, Air, Water 2008, 36 (2), 145?151. (and air conditioner. And in 2015, the additional nine types, including range hood, electric-water-

  5. Kinesthetic Learning in the Classroom "Great ideas originate in the muscles" Thomas Edison

    E-Print Network [OSTI]

    Tranquillo, Joseph V.

    community and may include instructor demonstrations, brainstorming, reflections and minute papers and soldering a circuit board, connecting and sealing tubes in a flow loop or drilling a precise hole will take place in the classroom with the objective of introducing and strengthening concepts as well

  6. ME 6222: Manufacturing Processes and Systems Prof. J.S. Colton GIT 2011

    E-Print Network [OSTI]

    Colton, Jonathan S.

    ME 6222: Manufacturing Processes and Systems Prof. J.S. Colton © GIT 2011 1 Joining ­ Part 2 ver. 1 #12;ME 6222: Manufacturing Processes and Systems Prof. J.S. Colton © GIT 2011 2 Overview · Mechanical · Diffusion bonding · Soldering and brazing · Fusion welding #12;ME 6222: Manufacturing Processes and Systems

  7. ME 4210: Manufacturing Processes and Engineering Prof. J.S. Colton GIT 2011

    E-Print Network [OSTI]

    Colton, Jonathan S.

    ME 4210: Manufacturing Processes and Engineering Prof. J.S. Colton © GIT 2011 1 Joining ver. 1 #12;ME 4210: Manufacturing Processes and Engineering Prof. J.S. Colton © GIT 2011 2 Overview · Welding using interfacial shear · Adhesive bonding · Soldering and brazing #12;ME 4210: Manufacturing Processes

  8. Possible Ideas on a New DCR Backplane Design Grant Hampson

    E-Print Network [OSTI]

    Ellingson, Steven W.

    cable [2]. 3. A backplane to provide a robust mounting mechanism to support the DCRs. By having no power sheet cover bolted down with six 4-40 screws.) Connectors (RF, LO, LVDS) are soldered to the rear. The backplane would support a Rabbit µController which would control a multi- channel DAC (1-4V output) which

  9. Effects of heat treatment and HF etching on the strength of silica lightguides

    E-Print Network [OSTI]

    Matthewson, M. John

    Effects of heat treatment and HF etching on the strength of silica lightguides C. R. Kurkjian, M. J, heating of a fiber to moderate temperatures (~300 600 C), for instance during the soldering of pigtails-lowering defects. In this paper we discuss early results from the literature on the effects of heating and HF

  10. Review of the MERIT Experiment Magnet Status and Testing Plans

    E-Print Network [OSTI]

    McDonald, Kirk

    Review of the MERIT Experiment Magnet Status and Testing Plans Monday December 10, 2005 Peter H;CVIP Vessel Manufacturing Status Final alignment of terminations was made. Gland nut components assembled well ad will be readily changed-out if needed. Instrumentation was assembled, -Not soldered

  11. Clean Energy Ambassadors The mission of the Clean Energy Institute is to accelerate the

    E-Print Network [OSTI]

    Hochberg, Michael

    technologies. Solar Panel Workshop- In this full day, (or 2 half day) high school workshop students design and build their own solar panel from individual cells. They learn to solder and predict the voltage of a clean energy future by advancing next generation solar energy and electrical energy storage materials

  12. Opto Working Group Meeting March 21, 2014

    E-Print Network [OSTI]

    Gan, K. K.

    Summary of failures after burn-in/thermal cycles Summary K.K. Gan #12;K.K. Gan Opto Working Group Implemented several improvements based on experience gained from production of 1st generation opto cold solder is a major cause of opto-link failures opto-boards built by OSU have ~0.1% broken

  13. UNIVERSITY OF WASHINGTON Hazardous Materials Environmental Health & Safety

    E-Print Network [OSTI]

    Sniadecki, Nathan J.

    to construction debris recycling facilities even if the lead concentrations are below Hazardous Waste levels in construction debris. It is most often found in pipes, copper pipes with lead solder, and interior and exterior, lead-containing materials have the potential to negatively impact the health of construction workers

  14. Cure cycle evaluation for multilayer printed wiring boards

    SciTech Connect (OSTI)

    Lula, J.W.

    1980-06-01

    The cure cycle for multilayer printed wiring boards (PWBs) made from general-puspore, fire-retardant epoxy/glass (GF) material has been evaluated for the optimum delamination resistance at soldering temperatures. The results that, for the epoxy resin system used to manufacture multilayer PWBs at Bendix Kansas City, a wide range of cure cycle variations has a minimal effect on delamination resistance.

  15. Improving delamination resistance of multilayer printed wiring boards

    SciTech Connect (OSTI)

    Lula, J.W.

    1980-03-01

    Bendix has incorporated black oxide innerlayer surface treatment and dry nitrogen prepreg conditioning into the manufacturing process for multilayer PWBs. Before these changes, interlaminar adhesion was marginal and delaminations regularly occurred during solder dipping and leveling. Since the implementation of these changes, Bendix has not experienced any delaminated multilayer PWBs, and they may be immersed in molten solder for 2 minutes or more without visual damage. Both black oxide and red oxide innerlayer surface treatments have shown the capability to provide acceptable delamination resistance for multilayer PWBs made from FR-4 material. Optimum processing parameters for applying the oxide treatment have been determined. In order to manufacture a multilayer PWB that will withstand solder dipping/leveling as well as subsequent drag soldering, its is necessary to remove absorbed moisture from the prepreg before lamination. Data have been gathered on the rate of moisutre removal from prepreg when dried and on the rate of moisture reabsorption when dried prepreg is exposed to 24/sup 0/C/50% RH environment.

  16. Lead Content of Brass Plumbing Components J Barry Maynard

    E-Print Network [OSTI]

    Maynard, J. Barry

    Lead Content of Brass Plumbing Components J Barry Maynard University of Cincinnati 2008 Water are leaded brass and hence comprise a potential source of Pb in compliance testing under the Lead and Copper be marketed as "lead free". In true no-lead brasses, Bi and Se are used in place of Pb (http

  17. International Journal of Minerals, Metallurgy and Materials V olume 20, Number 5, May 2013, Page 472

    E-Print Network [OSTI]

    Volinsky, Alex A.

    Pure tin electroplating has become the most popular surface coating process for lead-free electronic impedance spectroscopy (EIS), and microstructure analysis. In the absence of additives, tin coatings smoother and denser tin coating. The (112) crystal face is found to be the dominant and preferred

  18. Phosphate glasses for radioactive, hazardous and mixed waste immobilization

    DOE Patents [OSTI]

    Cao, H.; Adams, J.W.; Kalb, P.D.

    1998-11-24

    Lead-free phosphate glass compositions are provided which can be used to immobilize low level and/or high level radioactive wastes in monolithic waste forms. The glass composition may also be used without waste contained therein. Lead-free phosphate glass compositions prepared at about 900 C include mixtures from about 1--6 mole % iron (III) oxide, from about 1--6 mole % aluminum oxide, from about 15--20 mole % sodium oxide or potassium oxide, and from about 30--60 mole % phosphate. The invention also provides phosphate, lead-free glass ceramic glass compositions which are prepared from about 400 C to about 450 C and which includes from about 3--6 mole % sodium oxide, from about 20--50 mole % tin oxide, from about 30--70 mole % phosphate, from about 3--6 mole % aluminum oxide, from about 3--8 mole % silicon oxide, from about 0.5--2 mole % iron (III) oxide and from about 3--6 mole % potassium oxide. Method of making lead-free phosphate glasses are also provided. 8 figs.

  19. Phosphate glasses for radioactive, hazardous and mixed waste immobilization

    DOE Patents [OSTI]

    Cao, H.; Adams, J.W.; Kalb, P.D.

    1999-03-09

    Lead-free phosphate glass compositions are provided which can be used to immobilize low level and/or high level radioactive wastes in monolithic waste forms. The glass composition may also be used without waste contained therein. Lead-free phosphate glass compositions prepared at about 900 C include mixtures from about 1 mole % to about 6 mole % iron (III) oxide, from about 1 mole % to about 6 mole % aluminum oxide, from about 15 mole % to about 20 mole % sodium oxide or potassium oxide, and from about 30 mole % to about 60 mole % phosphate. The invention also provides phosphate, lead-free glass ceramic glass compositions which are prepared from about 400 C to about 450 C and which includes from about 3 mole % to about 6 mole % sodium oxide, from about 20 mole % to about 50 mole % tin oxide, from about 30 mole % to about 70 mole % phosphate, from about 3 mole % to about 6 mole % aluminum oxide, from about 3 mole % to about 8 mole % silicon oxide, from about 0.5 mole % to about 2 mole % iron (III) oxide and from about 3 mole % to about 6 mole % potassium oxide. Method of making lead-free phosphate glasses are also provided. 8 figs.

  20. Queensland's 1.7 million cars use nearly 3 billion litres of petrol

    E-Print Network [OSTI]

    Patzek, Tadeusz W.

    Queensland's 1.7 million cars use nearly 3 billion litres of petrol per year. In December 2001 to lead-free petrol without modification. "I have been running my car on E10 since June and two of my, the EPA's 85 fleet cars will then start using E10, and the facility will be available to vehicles from

  1. Exclusive License Non-Exclusive License

    E-Print Network [OSTI]

    Improved Power Conversion For Organic Photovoltaics Lead-Free Solar Cells All-Carbon Counter Electrode-typeTransparent Conductors Electron-Blocking Layer For Organic Photovoltaics Organic Photovoltaics with Nickel Oxide Hole Graphene Oxide Solid State Solar Cell Improved Nanoparticle Processing for Energy Use Solar Cell Coating

  2. Exclusive License Non-Exclusive License

    E-Print Network [OSTI]

    Photovoltaic Cells Improved Power Conversion For Organic Photovoltaics Lead-Free Solar Cells All-Carbon Counter Cell p-typeTransparent Conductors Electron-Blocking Layer For Organic Photovoltaics Organic Photovoltaics with Nickel Oxide Hole Array Films Novel Organic Self-Assembled Nanodielectrics Hybrid

  3. Explosive complexes

    DOE Patents [OSTI]

    Huynh, My Hang V. (Los Alamos, NM)

    2011-08-16

    Lead-free primary explosives of the formula [M.sup.II(A).sub.R(B.sup.X).sub.S](C.sup.Y).sub.T, where A is 1,5-diaminotetrazole, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  4. List of Publications (Reverse Chronological Order) Click on the blue publication numbers to access the full text pdfs. You may need to be logged in to your institution web pages

    E-Print Network [OSTI]

    Ojovan, Michael

    Properties of Ca-Doped BiFeO3 Ceramics: From p-Type Semiconduction to Oxide-Ion Conduction, Nahum Masó and lead-free Ba2NdTi2Nb3O15 ceramics, L. Burianova, S. Panos, M. C. Stennett, A. R. West, G Subodh, M. T

  5. Barium Titanate and Bismuth Oxide Nanocomposites Barium titanate, BaTiO3, and bismuth oxide Bi2O3 are transparent materials with

    E-Print Network [OSTI]

    Harmon, Julie P.

    Barium Titanate and Bismuth Oxide Nanocomposites Barium titanate, BaTiO3, and bismuth oxide Bi2O3 that are lead-free. If we cannot shield effectively at nanofiller levels where transparency is maintained, we, Condensed Matter, Vol. 15, 8927 (2003). 21. "Highly Nonlinear Bismuth-Oxide Fiber for Smooth Supercontinuun

  6. Phase transition and ferroelectric properties of epitaxially strained KNbO3/NaNbO3 superlattice

    E-Print Network [OSTI]

    Cao, Wenwu

    , because lead oxide vaporizes during the fabrica- tion process, which is harmful to the environment: 10.1063/1.3053148 Lead based piezoelectric ceramic Pb Zr1-xTix O3 PZT has been widely used, the devel- opment of lead-free ferroelectric materials with properties comparable to lead based compounds

  7. Phosphate glasses for radioactive, hazardous and mixed waste immobilization

    DOE Patents [OSTI]

    Cao, Hui (Middle Island, NY); Adams, Jay W. (Stony Brook, NY); Kalb, Paul D. (Wading River, NY)

    1999-03-09

    Lead-free phosphate glass compositions are provided which can be used to immobilize low level and/or high level radioactive wastes in monolithic waste forms. The glass composition may also be used without waste contained therein. Lead-free phosphate glass compositions prepared at about 900.degree. C. include mixtures from about 1 mole % to about 6 mole %.iron (III) oxide, from about 1 mole % to about 6 mole % aluminum oxide, from about 15 mole % to about 20 mole % sodium oxide or potassium oxide, and from about 30 mole % to about 60 mole % phosphate. The invention also provides phosphate, lead-free glass ceramic glass compositions which are prepared from about 400.degree. C. to about 450.degree. C. and which includes from about 3 mole % to about 6 mole % sodium oxide, from about 20 mole % to about 50 mole % tin oxide, from about 30 mole % to about 70 mole % phosphate, from about 3 mole % to about 6 mole % aluminum oxide, from about 3 mole % to about 8 mole % silicon oxide, from about 0.5 mole % to about 2 mole % iron (III) oxide and from about 3 mole % to about 6 mole % potassium oxide. Method of making lead-free phosphate glasses are also provided.

  8. Phosphate glasses for radioactive, hazardous and mixed waste immobilization

    DOE Patents [OSTI]

    Cao, Hui (Middle Island, NY); Adams, Jay W. (Stony Brook, NY); Kalb, Paul D. (Wading River, NY)

    1998-11-24

    Lead-free phosphate glass compositions are provided which can be used to immobilize low level and/or high level radioactive wastes in monolithic waste forms. The glass composition may also be used without waste contained therein. Lead-free phosphate glass compositions prepared at about 900.degree. C. include mixtures from about 1 mole % to about 6 mole % iron (III) oxide, from about 1 mole % to about 6 mole % aluminum oxide, from about 15 mole % to about 20 mole % sodium oxide or potassium oxide, and from about 30 mole % to about 60 mole % phosphate. The invention also provides phosphate, lead-free glass ceramic glass compositions which are prepared from about 400.degree. C. to about 450.degree. C. and which includes from about 3 mole % to about 6 mole % sodium oxide, from about 20 mole % to about 50 mole % tin oxide, from about 30 mole % to about 70 mole % phosphate, from about 3 mole % to about 6 mole % aluminum oxide, from about 3 mole % to about 8 mole % silicon oxide, from about 0.5 mole % to about 2 mole % iron (III) oxide and from about 3 mole % to about 6 mole % potassium oxide. Method of making lead-free phosphate glasses are also provided.

  9. High thermoelectric performance by resonant dopant indium in nanostructured SnTe

    E-Print Network [OSTI]

    Liao, Bolin

    From an environmental perspective, lead-free SnTe would be preferable for solid-state waste heat recovery if its thermoelectric figure-of-merit could be brought close to that of the lead-containing chalcogenides. In this ...

  10. Domain Engineering for Enhanced Ferroelectric Properties of Epitaxial (001) BiFeO Thin Films

    E-Print Network [OSTI]

    Eom, Chang Beom

    Domain Engineering for Enhanced Ferroelectric Properties of Epitaxial (001) BiFeO Thin Films By Ho of conventional Ti-rich lead zirconia titanate, suggested BiFeO3 as a strong candidate for lead-free nonvolatile are simultaneously improved by domain engineering. For the demonstration of the domain variant selection in BiFeO3

  11. Explosive complexes

    DOE Patents [OSTI]

    Huynh, My Hang V. (Los Alamos, NM)

    2009-09-22

    Lead-free primary explosives of the formula [M.sup.II(A).sub.R(B.sup.X).sub.S](C.sup.Y).sub.T, where A is 1,5-diaminotetrazole, and syntheses thereof are described. Substantially stoichiometric equivalents of the reactants lead to high yields of pure compositions thereby avoiding dangerous purification steps.

  12. Seymour Center offers guided tours on the Santa Cruz wharf SANTA CRUZ, CA--In collaboration with the City of Santa Cruz, UCSC's Seymour

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Seymour Center offers guided tours on the Santa Cruz wharf SANTA CRUZ, CA--In collaboration with the City of Santa Cruz, UCSC's Seymour Marine Discovery Center is now leading free 30-minute public tours on the Santa Cruz Municipal Wharf every Saturday and Sunday at 1 and 3 p.m. The Seymour Center's marine science

  13. Water supplier copes with lead paint removal regs

    SciTech Connect (OSTI)

    Becker, C.E. ); Lovejoy, D.R.; Bryck, J.L.; Rockensies, W.H.

    1993-12-01

    This article examines new paint removal methods that minimize releasing of paints containing lead to the environment and lead free coating systems for tank corrosion protection used in the Village of Freeport in Long Island, New York. The topics of the article include coating failures, removal tools and methods, paint and application methods.

  14. The role of electroplated coatings in metal joining

    SciTech Connect (OSTI)

    Dini, J.W. [Lawrence Livermore National Lab., CA (United States)

    1996-05-01

    Electroplated and electroless coatings often play an important role in soldering, brazing, and welding operations. Thin deposits applied to critical surfaces before the joining operations can provide the difference between success and failure. Diffusion welding applications sometimes require coatings to help promote joining. For some applications, electroplating by itself can be used to join metals that cannot be welded or brazed because of metallurgical incompatibility. The use of electroplated coatings for these various joining applications is reviewed here.

  15. Development of the bus joint for the ITER Central Solenoid

    SciTech Connect (OSTI)

    Martovetsky, Nicolai N; Irick, David Kim; Kenney, Steven J

    2013-01-01

    The terminations of the Central Solenoid (CS) modules are connected to the bus extensions by joints located outside the CS in the gap between the CS and Torodial Field (TF) assemblies. These joints have very strict space limitations. Low resistance is a common requirement for all ITER joints. In addition, the CS bus joints will experience and must be designed to withstand significant variation in the magnetic field of several tenths of a Tesla per second during initiation of plasma. The joint resistance is specified to be less than 4 nOhm. The joints also have to be soldered in the field and designed with the possibility to be installed and dismantled in order to allow cold testing in the cold test facility. We have developed coaxial joints that meet these requirements and have demonstrated the feasibility to fabricate and assemble them in the vertical configuration. We introduced a coupling cylinder with superconducting strands soldered to the surface of the cable that can be installed in the ITER assembly hall and at the Cold Test Facility. This cylinder serves as a transition area between the CS module and the bus extension. We made two racetrack samples and tested four bus joints in our Joint Test Apparatus. Resistance of the bus joints was measured by a decay method and by a microvoltmeter; the value of the current was measured by the Hall probes. This measurement method was verified in the previous tests. The resistance of the joints varied insignificantly from 1.5 to 2 nOhm. One of the challenges associated with a soldered joint is the inability to use corrosive chemicals that are difficult to clean. This paper describes our development work on cable preparation, chrome removal, compaction, soldering, and final assembly and presents the test results.

  16. Planar triode pulser socket

    DOE Patents [OSTI]

    Booth, R.

    1994-10-25

    A planar triode is mounted in a PC board orifice by means of a U-shaped capacitor housing and anode contact yoke removably attached to cathode leg extensions passing through and soldered to the cathode side of the PC board by means of a PC cathode pad. A pliant/flexible contact attached to the orifice make triode grid contact with a grid pad on the grid side of the PC board, permitting quick and easy replacement of bad triodes. 14 figs.

  17. Robust design using sequential computer experiments 

    E-Print Network [OSTI]

    Gupta, Abhishek

    2004-09-30

    step for robust design is to classify the input factors as controllable factors or design variables, xc, and noise factors or environmental variables, xe. We suppose the domain of y is ? which is a fixed subset of d and ?ec x . The process... follows the style and format of ASME Journal of Manufacturing Science and Engineering. 2 • PWB thickness & material properties • Component properties • Interconnect geometry Bending von Mises stress of critical solder joints INPUTS: x...

  18. Low resistivity contact to iron-pnictide superconductors

    DOE Patents [OSTI]

    Tanatar, Makariy; Prozorov, Ruslan; Ni, Ni; Bud'ko, Sergey; Canfield, Paul

    2013-05-28

    Method of making a low resistivity electrical connection between an electrical conductor and an iron pnictide superconductor involves connecting the electrical conductor and superconductor using a tin or tin-based material therebetween, such as using a tin or tin-based solder. The superconductor can be based on doped AFe.sub.2As.sub.2, where A can be Ca, Sr, Ba, Eu or combinations thereof for purposes of illustration only.

  19. Polyimide/glass multilayer printed wiring boards. Final report

    SciTech Connect (OSTI)

    Lula, J.W.

    1984-07-01

    Multilayer printed wiring boards (PWBs) were manufactured from a polyimide/glass reinforced copper-clad laminate and prepreg. A lamination cycle and innerlayer copper surface treatment were developed that gave satisfactory delamination resistance at soldering temperatures. When compared to similar epoxy/glass multilayer PWBs, the polyimide PWBs had higher thermal stability, greater resistance to raised lands, fewer plating voids, less outgassing, and adhesion that was equivalent to urethane foam encapsulants.

  20. In situ study on the effect of thermomigration on intermetallic compounds growth in liquid-solid interfacial reaction

    SciTech Connect (OSTI)

    Qu, Lin; Zhao, Ning; Ma, Haitao, E-mail: htma@dlut.edu.cn; Zhao, Huijing; Huang, Mingliang [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085 (China)

    2014-05-28

    Synchrotron radiation real-time imaging technology was carried out in situ to observe and characterize the effect of thermomigration on the growth behavior of interfacial intermetallic compounds (IMCs) in Cu/Sn/Cu solder joint during soldering. The thermomigration resulted in asymmetrical formation and growth of the interfacial IMCs. Cu{sub 6}Sn{sub 5} and Cu{sub 3}Sn IMCs formed at the cold end and grew rapidly during the whole soldering process. However, only Cu{sub 6}Sn{sub 5} IMC formed at the hot end and remained relatively thin until solidification. The IMCs at the cold end were nearly seven times thicker than that at the hot end after solidification. The Cu dissolution at the cold end was significantly restrained, while that at the hot end was promoted, which supplied Cu atoms to diffuse toward the cold end under thermomigration to feed the rapid IMC growth. Moreover, the thermomigration also caused asymmetrical morphology of the interfacial IMCs at the cooling stage, i.e., the Cu{sub 6}Sn{sub 5} IMC at the cold end transformed into facet structure, while that at the hot end remained scallop-type. The asymmetrical growth behavior of the interfacial IMCs was analyzed from the view point of kinetics.

  1. Thermal cycling tests on surface-mount assemblies

    SciTech Connect (OSTI)

    Jennings, C.W.

    1988-03-01

    The capability of surface-mount (SM) solder joints to withstand various thermal cycle stresses was evaluated through electrical circuit resistance changes of a test pattern and by visual examination for cracks in the solder after exposure to thermal cycling. The joints connected different electrical components, primarily leadless-chip carriers (LCCs), and printed wiring-board (PWB) pads on different laminate substrates. Laminate compositions were epoxy-glass and polyimide-glass with and without copper/Invar/copper (CIC) inner layers, polyimide-quartz, epoxy-Kevlar, and polyimide-Kevlar. The most resistant joints were between small LCCs (24 and 48 pins) and polyimide-glass laminate with CIC inner layers. Processing in joint formation was found to be an important part of joint resistant. Thermal cycling was varied with respect to both time and temperature. A few resistors, capacitors, and inductors showed opens after 500 30-min cycles between -65/degree/C and 125/degree/C. Appreciable moisture contents were measured for laminate materials, especially those of polyimide-Kevlar after equilibration in 100/percent/ relative humidity at room temperature. If not removed or reduced, moisture can cause delamination in vapor-phase soldering. 17 refs, 12 figs.,10 tabs.

  2. A Dirichlet reputation system in reliable routing of wireless ad hoc network

    SciTech Connect (OSTI)

    Yang, Dr. Li [University of Tennessee, Knoxville (UTK); Cui, Xiaohui [ORNL; Cemerlic, Alma [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Ad hoc networks are very helpful in situations when no fixed network infrastructure is available, such as natural disasters and military conflicts. In such a network, all wireless nodes are equal peers simultaneously serving as both senders and routers for other nodes. Therefore, how to route packets through reliable paths becomes a fundamental problems when behaviors of certain nodes deviate from wireless ad hoc routing protocols. We proposed a novel Dirichlet reputation model based on Bayesian inference theory which evaluates reliability of each node in terms of packet delivery. Our system offers a way to predict and select a reliable path through combination of first-hand observation and second-hand reputation reports. We also proposed moving window mechanism which helps to adjust ours responsiveness of our system to changes of node behaviors. We integrated the Dirichlet reputation into routing protocol of wireless ad hoc networks. Our extensive simulation indicates that our proposed reputation system can improve good throughput of the network and reduce negative impacts caused by misbehaving nodes.

  3. Tin electroplating/stripping evaluation. Topical report

    SciTech Connect (OSTI)

    McHenry, M.R.

    1995-08-01

    An evaluation was conducted to determine possible replacement chemistries for electroplating and stripping of tin-lead. The driver for this project was two-fold. Our first goal dealt with hazardous waste reduction. It was desired to eliminate lead (a heavy metal) from the electroplating process and thiourea (a known carcinogen) from the stripping process. We also sought to reduce the cost of nonconformance (CONC) realized by this process in the form of rough plating, broken paths, poor solderability, and overetching. Three suppliers` tin chemistries were evaluated as replacements for electroplating and stripping of tin-lead. Based on preliminary testing, one chemistry was chosen, evaluated, and approved for production use.

  4. New method for sand control and well stimulation in unconsolidated dirty sands

    SciTech Connect (OSTI)

    Aslesen, K.S.; Short, C.J.; Terwilliger, P.L.

    1981-01-01

    A new technique, the Solder Glass sand consolidation well completion method, has been developed which allows unlimited drawdown and improves productivity in wells completed in unconsolidated formations containing shales and clays. This technique eliminates the problems of sand production and fines migration by artificially consolidating a volume of reservoir sand near the wellbore. The consolidation is resistant to high temperature, chemical attack, and degradation resulting from high velocity fluid flow. Additionally, porosity and permeability in the consolidated volume of reservoir sand are improved as a result of irreversible dehydration of clays. 12 refs.

  5. Development of manufacturing capability for the fabrication of the Nb/sub 3/Sn superconductor for the High Field Test Facility. Final report

    SciTech Connect (OSTI)

    Spencer, C R

    1981-01-01

    Construction of High Field Test Facility (HFTF) at Lawrence Livermore Laboratory (LLNL) requires an extended surface Nb/sub 3/Sn superconductor cable of carrying currents in excess of 7500 amperes in a 12 Tesla magnetic field. This conductor consists of a 5.4 mm x 11.0 mm superconducting core onto whose broad surfaces are soldered embossed oxygen free copper strips. Two different core designs have been developed and the feasibility of each design evaluated. Equipment necessary to produce the conductor were developed and techniques of production were explored.

  6. Development of Safe Methods for Canning Blackeye Peas at Home. 

    E-Print Network [OSTI]

    Crawford, Ellen G.; Sheppard, M. Patricia; Smith, Annie B.; Cover, Sylvia

    1948-01-01

    AGRICULTURAL AND MECHANICAL COLLEGE SYSTEM GIBB GILCHRIST, Chancellor The Cover Picture A load OF pint jars OF blackeye peas is being removed fro111 the canner. Three of the 16 jars were used for ireat penetration tests. The tliermocouple wires were... inserted in the jars by means of tlie flat type stuffing !,ox soldered to the lid. One jar ~\\~itll a tlrern~o- couple attached is on the table, another may be seen in the top layer in tlie canner and the third is in the bottonl layel- of tlie canner...

  7. Packaging of solid state devices

    DOE Patents [OSTI]

    Glidden, Steven C.; Sanders, Howard D.

    2006-01-03

    A package for one or more solid state devices in a single module that allows for operation at high voltage, high current, or both high voltage and high current. Low thermal resistance between the solid state devices and an exterior of the package and matched coefficient of thermal expansion between the solid state devices and the materials used in packaging enables high power operation. The solid state devices are soldered between two layers of ceramic with metal traces that interconnect the devices and external contacts. This approach provides a simple method for assembling and encapsulating high power solid state devices.

  8. Method of fabricating a solar cell array

    DOE Patents [OSTI]

    Lazzery, Angelo G. (Oaklyn, NJ); Crouthamel, Marvin S. (Pennsauken, NJ); Coyle, Peter J. (Oaklyn, NJ)

    1982-01-01

    A first set of pre-tabbed solar cells are assembled in a predetermined array with at least part of each tab facing upward, each tab being fixed to a bonding pad on one cell and abutting a bonding pad on an adjacent cell. The cells are held in place with a first vacuum support. The array is then inverted onto a second vacuum support which holds the tabs firmly against the cell pads they abut. The cells are exposed to radiation to melt and reflow the solder pads for bonding the tab portions not already fixed to bonding pads to these pads.

  9. Magnetically attached sputter targets

    DOE Patents [OSTI]

    Makowiecki, D.M.; McKernan, M.A.

    1994-02-15

    An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

  10. Repairable chip bonding/interconnect process

    DOE Patents [OSTI]

    Bernhardt, Anthony F. (Berkeley, CA); Contolini, Robert J. (Livermore, CA); Malba, Vincent (Livermore, CA); Riddle, Robert A. (Tracy, CA)

    1997-01-01

    A repairable, chip-to-board interconnect process which addresses cost and testability issues in the multi-chip modules. This process can be carried out using a chip-on-sacrificial-substrate technique, involving laser processing. This process avoids the curing/solvent evolution problems encountered in prior approaches, as well is resolving prior plating problems and the requirements for fillets. For repairable high speed chip-to-board connection, transmission lines can be formed on the sides of the chip from chip bond pads, ending in a gull wing at the bottom of the chip for subsequent solder.

  11. Repairable chip bonding/interconnect process

    DOE Patents [OSTI]

    Bernhardt, A.F.; Contolini, R.J.; Malba, V.; Riddle, R.A.

    1997-08-05

    A repairable, chip-to-board interconnect process which addresses cost and testability issues in the multi-chip modules is disclosed. This process can be carried out using a chip-on-sacrificial-substrate technique, involving laser processing. This process avoids the curing/solvent evolution problems encountered in prior approaches, as well is resolving prior plating problems and the requirements for fillets. For repairable high speed chip-to-board connection, transmission lines can be formed on the sides of the chip from chip bond pads, ending in a gull wing at the bottom of the chip for subsequent solder. 10 figs.

  12. Programmable Multi-Chip Module

    DOE Patents [OSTI]

    Kautz, David (Lenexa, KS); Morgenstern, Howard (Lee's Summit, MO); Blazek, Roy J. (Overland Park, KS)

    2005-05-24

    A multi-chip module comprising a low-temperature co-fired ceramic substrate having a first side on which are mounted active components and a second side on which are mounted passive components, wherein this segregation of components allows for hermetically sealing the active components with a cover while leaving accessible the passive components, and wherein the passive components are secured using a reflow soldering technique and are removable and replaceable so as to make the multi-chip module substantially programmable with regard to the passive components.

  13. Programmable Multi-Chip Module

    DOE Patents [OSTI]

    Kautz, David (Lenexa, KS); Morgenstern, Howard (Lee's Summit, MO); Blazek, Roy J. (Overland Park, KS)

    2004-11-16

    A multi-chip module comprising a low-temperature co-fired ceramic substrate having a first side on which are mounted active components and a second side on which are mounted passive components, wherein this segregation of components allows for hermetically sealing the active components with a cover while leaving accessible the passive components, and wherein the passive components are secured using a reflow soldering technique and are removable and replaceable so as to make the multi-chip module substantially programmable with regard to the passive components.

  14. Programmable multi-chip module

    DOE Patents [OSTI]

    Kautz, David; Morgenstern, Howard; Blazek, Roy J.

    2004-03-02

    A multi-chip module comprising a low-temperature co-fired ceramic substrate having a first side on which are mounted active components and a second side on which are mounted passive components, wherein this segregation of components allows for hermetically sealing the active components with a cover while leaving accessible the passive components, and wherein the passive components are secured using a reflow soldering technique and are removable and replaceable so as to make the multi-chip module substantially programmable with regard to the passive components.

  15. FMEA on the superconducting torus for the Jefferson Lab 12 GeV accelerator upgrade

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

    Ghoshal, Probir K.; Biallas, George H.; Fair, Ruben J.; Rajput-Ghoshal, Renuka; Schneider, William J.; Legg, Robert A.; Kashy, David H.; Hogan, John P.; Wiseman, Mark A.; Luongo, Cesar; et al

    2015-01-16

    As part of the Jefferson Lab 12GeV accelerator upgrade project, Hall B requires two conduction cooled superconducting magnets. One is a magnet system consisting of six superconducting trapezoidal racetrack-type coils assembled in a toroidal configuration and the second is an actively shielded solenoidal magnet system consisting of 5 coils. Both magnets are to be wound with Superconducting Super Collider-36 NbTi strand Rutherford cable soldered into a copper channel. This paper describes the various failure modes in torus magnet along with the failure modes that could be experienced by the torus and its interaction with the solenoid which is located inmore »close proximity.« less

  16. Copper-to-silicon-carbide joints development for Future CLIC Hom Dampers

    E-Print Network [OSTI]

    Gil Costa, Miguel

    2015-01-01

    Ceramic-to-metal joints have been of paramount importance for the nuclear and aeronautic industry since the last century. In this document, two different approaches to the Cu-to-SiC joining are briefly described and discussed. The first approach consists of an intermediate piece of lower Coefficient of Thermal Expansion than copper aiming to reduce the expansion mismatch with the ceramic during the brazing cycle. Soldering is selected as a second attempt, whose lower joining temperature reduces the absolute expansion difference between Cu and SiC. In addition, four SiC metallization processes are proposed and some of them have been also tested and discussed.

  17. Method of monolithic module assembly

    DOE Patents [OSTI]

    Gee, James M. (Albuquerque, NM); Garrett, Stephen E. (Albuquerque, NM); Morgan, William P. (Albuquerque, NM); Worobey, Walter (Albuquerque, NM)

    1999-01-01

    Methods for "monolithic module assembly" which translate many of the advantages of monolithic module construction of thin-film PV modules to wafered c-Si PV modules. Methods employ using back-contact solar cells positioned atop electrically conductive circuit elements affixed to a planar support so that a circuit capable of generating electric power is created. The modules are encapsulated using encapsulant materials such as EVA which are commonly used in photovoltaic module manufacture. The methods of the invention allow multiple cells to be electrically connected in a single encapsulation step rather than by sequential soldering which characterizes the currently used commercial practices.

  18. Design of a Probe for Strain Sensitivity Studies of Critical Current Densities in SC Wires and Tapes

    SciTech Connect (OSTI)

    Dhanaraj, N.; Barzi, E.; Turrioni, D.; Rusy, A.; Lombardo, V.; /Fermilab

    2011-07-01

    The design of a variable-temperature probe used to perform strain sensitivity measurements on LTS wires and HTS wires and tapes is described. The measurements are intended to be performed at liquid helium temperatures (4.2 K). The wire or tape to be measured is wound and soldered on to a helical spring device, which is fixed at one end and subjected to a torque at the free end. The design goal is to be able to achieve {+-} 0.8 % strain in the wire and tape. The probe is designed to carry a current of 2000A.

  19. Laminated photovoltaic modules using back-contact solar cells

    DOE Patents [OSTI]

    Gee, James M. (Albuquerque, NM); Garrett, Stephen E. (Albuquerque, NM); Morgan, William P. (Albuquerque, NM); Worobey, Walter (Albuquerque, NM)

    1999-09-14

    Photovoltaic modules which comprise back-contact solar cells, such as back-contact crystalline silicon solar cells, positioned atop electrically conductive circuit elements affixed to a planar support so that a circuit capable of generating electric power is created. The modules are encapsulated using encapsulant materials such as EVA which are commonly used in photovoltaic module manufacture. The module designs allow multiple cells to be electrically connected in a single encapsulation step rather than by sequential soldering which characterizes the currently used commercial practices.

  20. Functionally graded alumina-based thin film systems

    DOE Patents [OSTI]

    Moore, John J.; Zhong, Dalong

    2006-08-29

    The present invention provides coating systems that minimize thermal and residual stresses to create a fatigue- and soldering-resistant coating for aluminum die casting dies. The coating systems include at least three layers. The outer layer is an alumina- or boro-carbide-based outer layer that has superior non-wettability characteristics with molten aluminum coupled with oxidation and wear resistance. A functionally-graded intermediate layer or "interlayer" enhances the erosive wear, toughness, and corrosion resistance of the die. A thin adhesion layer of reactive metal is used between the die substrate and the interlayer to increase adhesion of the coating system to the die surface.

  1. Phase 2 of the array automated assembly task for the low cost silicon solar array project. Final report

    SciTech Connect (OSTI)

    Petersen, R.C.

    1980-11-01

    Studies were conducted on several fundamental aspects of electroless nickel/solder metallization for silicon solar cells. A process proposed by Motorola, which precedes the electroless nickel plating with several steps of palladium plating and heat treatment, was compared directly with single step electroless nickel plating. Work has directed toward answering specific questions concerning the effect of silicon surface oxide on nickel plating, effects of thermal stresses on the metallization, sintering of nickel plated on silicon, and effects of exposure to the plating solution on solar cell characteristics. The Motorola process was compared with simple electroless nickel plating in a series of parallel experiments. Results are presented. (WHK)

  2. Direct cooled power electronics substrate

    DOE Patents [OSTI]

    Wiles, Randy H [Powell, TN; Wereszczak, Andrew A [Oak Ridge, TN; Ayers, Curtis W. (Kingston, TN) [Kingston, TN; Lowe, Kirk T. (Knoxville, TN) [Knoxville, TN

    2010-09-14

    The disclosure describes directly cooling a three-dimensional, direct metallization (DM) layer in a power electronics device. To enable sufficient cooling, coolant flow channels are formed within the ceramic substrate. The direct metallization layer (typically copper) may be bonded to the ceramic substrate, and semiconductor chips (such as IGBT and diodes) may be soldered or sintered onto the direct metallization layer to form a power electronics module. Multiple modules may be attached to cooling headers that provide in-flow and out-flow of coolant through the channels in the ceramic substrate. The modules and cooling header assembly are preferably sized to fit inside the core of a toroidal shaped capacitor.

  3. The rebuilding and repairing of electric motors and generators

    E-Print Network [OSTI]

    Ridenour, Roy Everett

    1918-01-01

    Motor After Coils had been Put Back in Place In the repairing and rebuilding of electric motors and generators there are three principal factors which must be considered. These factors are, service, cost and reliability. If a machine can easily... motor. This motor had been through a fire in a Cripple Creek mine. The insulation had been burned from the coils except in the slots where mica had been used. The solder was*melted from the rotor and the babbitt from the bearings. Water had been...

  4. GOMA 6.0 : a full-Newton finite element program for free and moving boundary problems with coupled fluid/solid momentum, energy, mass, and chemical species transport : user%3CU%2B2019%3Es guide.

    SciTech Connect (OSTI)

    Schunk, Peter Randall; Rao, Rekha Ranjana; Chen, Ken Shuang; Labreche, Duane A.; Sun, Amy Cha-Tien; Hopkins, Matthew Morgan; Moffat, Harry K.; Roach, Robert Allen; Hopkins, Polly L.; Notz, Patrick K.; Roberts, Scott Alan; Sackinger, Philip A.; Subia, Samuel Ramirez; Wilkes, Edward Dean; Baer, Thomas A.; Noble, David R.; Secor, Robert B.

    2013-07-01

    Goma 6.0 is a finite element program which excels in analyses of multiphysical processes, particularly those involving the major branches of mechanics (viz. fluid/solid mechanics, energy transport and chemical species transport). Goma is based on a full-Newton-coupled algorithm which allows for simultaneous solution of the governing principles, making the code ideally suited for problems involving closely coupled bulk mechanics and interfacial phenomena. Example applications include, but are not limited to, coating and polymer processing flows, super-alloy processing, welding/soldering, electrochemical processes, and solid-network or solution film drying. This document serves as a user's guide and reference.

  5. Printed wiring board fabrication and lead elimination via single-bath electrodeposition

    SciTech Connect (OSTI)

    Meltzer, M P; Steffani, C P

    2001-02-21

    Printed wiring board (PWB) fabrication, an operation performed both at LLNL and throughout the electronics industry, generates considerable quantities of hazardous waste, notably lead-bearing materials used for soldering, tinning, and finish coating the circuits of the board. Hot-air solder leveling (HASL), the most common method of finishing is one of the main sources of hazardous lead-bearing wastes in traditional PWB manufacturing. The development of a safer finishing method will lead to employee health and environmental benefits. In addition, there is a production advantage to eliminating HASL, for it provides a fairly uneven surface that is problematic for mounting very small components. In this project, we developed ''single-bath electroplating'' as a potential HASL replacement technology for many applications. Single-bath electroplating involves alternating deposition of one or the other metal component of a bimetal bath, through control of plating potential and mass transport. It employs a nickel layer as both etch resist and finish coat and has the potential for lowering environmental and human-health risks associated with PWB manufacture--while at the same time reconfiguring the process for greater efficiency and profitability.

  6. Phase transformations during the Ag-In plating and bonding of vertical diode elements of multijunction solar cells

    SciTech Connect (OSTI)

    Klochko, N. P. Khrypunov, G. S.; Volkova, N. D.; Kopach, V. R.; Lyubov, V. N.; Kirichenko, M. V.; Momotenko, A. V.; Kharchenko, N. M.; Nikitin, V. A.

    2013-06-15

    The conditions of the bonding of silicon multijunction solar cells with vertical p-n junctions using Ag-In solder are studied. The compositions of electrodeposited indium films on silicon wafers silver plated by screen printing and silver and indium films fabricated by layer-by-layer electrochemical deposition onto the surface of silicon vertical diode cells silver plated in vacuum are studied. Studying the electrochemical-deposition conditions, structure, and surface morphology of the grown layers showed that guaranteed bonding is provided by 8-min heat treatment at 400 Degree-Sign C under the pressure of a stack of metallized silicon wafers; however, the ratio of the indium and silver layer thicknesses should not exceed 1: 3. As this condition is satisfied, the solder after wafer bonding has the InAg{sub 3} structure (or InAg{sub 3} with an Ag phase admixture), due to which the junction melting point exceeds 700 Degree-Sign C, which guarantees the functioning of such solar cells under concentrated illumination.

  7. Electrical and thermal finite element modeling of arc faults in photovoltaic bypass diodes.

    SciTech Connect (OSTI)

    Bower, Ward Isaac; Quintana, Michael A.; Johnson, Jay

    2012-01-01

    Arc faults in photovoltaic (PV) modules have caused multiple rooftop fires. The arc generates a high-temperature plasma that ignites surrounding materials and subsequently spreads the fire to the building structure. While there are many possible locations in PV systems and PV modules where arcs could initiate, bypass diodes have been suspected of triggering arc faults in some modules. In order to understand the electrical and thermal phenomena associated with these events, a finite element model of a busbar and diode was created. Thermoelectrical simulations found Joule and internal diode heating from normal operation would not normally cause bypass diode or solder failures. However, if corrosion increased the contact resistance in the solder connection between the busbar and the diode leads, enough voltage potentially would be established to arc across micron-scale electrode gaps. Lastly, an analytical arc radiation model based on observed data was employed to predicted polymer ignition times. The model predicted polymer materials in the adjacent area of the diode and junction box ignite in less than 0.1 seconds.

  8. Experimental studies of helical solenoid model based on YBCO tape-bridge joints

    SciTech Connect (OSTI)

    Yu, M.; Lombardo, V.; Turrioni, D.; Zlobin, A.V.; Flangan, G.; Lopes, M.L.; Johnson, R.P.; /Fermilab

    2011-06-01

    Helical solenoids that provide solenoid, helical dipole and helical gradient field components are designed for a helical cooling channel (HCC) proposed for cooling of muon beams in a muon collider. The high temperature superconductor (HTS), 12 mm wide and 0.1 mm thick YBCO tape, is used as the conductor for the highest-field section of HCC due to certain advantages, such as its electrical and mechanical properties. To study and address the design, and technological and performance issues related to magnets based on YBCO tapes, a short helical solenoid model based on double-pancake coils was designed, fabricated and tested at Fermilab. Splicing joints were made with Sn-Pb solder as the power leads and the connection between coils, which is the most critical element in the magnet that can limit the performance significantly. This paper summarizes the test results of YBCO tape and double-pancake coils in liquid nitrogen and liquid helium, and then focuses on the study of YBCO splices, including the soldering temperatures and pressures, and splice bending test.

  9. Silicone injection restores failing submarine cables

    SciTech Connect (OSTI)

    Tilstra, M.

    1995-12-01

    Faced with the prospect of replacing nearly 10 miles of aging undersea cables, Orcas Power & Light Co (Opalco) elected instead to inject silicone into as many of the cables as possible. Silicone injection has been used extensively on underground residential distribution (URD) and feeder cables, but only two underwater cables had previously been injected: a feeder cable for Florida Power Corp under an intercoastal waterway and a cable for Washington Water Power Co under a lake in western Idaho. The compound restores power cables damaged by water treeing and prevents further water damage. Selection criteria included age, type, and whether the cables had ever been spliced. Older, soldered, hand-wrapped splices were avoided as they block the CableCure fluid from flowing through. This makes the cable uninjectable unless the splices are replaced with the molded type. The first cables chosen for injection were between 15 and 30 years old and clear of soldered splices. They also were free from faults. 4 figs.

  10. Non-Destructive Testing of Bus-Bar Joints Powering LHC Superconducting Magnets, by Using Gamma Sources

    E-Print Network [OSTI]

    Skoczen, B

    2004-01-01

    The main LHC superconducting magnets (dipoles and quadrupoles) use Rutherford type cables, stabilized electrically and thermally with copper profiles. The portions of cables are connected to each other by a soft soldering technique (Sn96Ag4) with an overlapping length corresponding to one pitch of the superconducting strands. The splice constitutes a "composite" structure with the interchanging layers of Sn96Ag4 and NbTi superconductor, located inside a Cu cage. In order to ensure a high level of reliability (failure probability not exceeding 10-8) for some 10000 connections in the LHC, a non-destructive technique to check the quantity of solder in the joint is foreseen. The technique is based on a gamma ray source (241Am) and the detection is position-sensitive in the transmission mode. Scintillating detectors of gamma rays are used and their accumulated length corresponds to the length of the radioactive source (120 mm). The method can be used in-situ, the equipment being optimized and portable, with implem...

  11. Micromechanical die attachment surcharge

    DOE Patents [OSTI]

    Filter, William F. (Albuquerque, NM); Hohimer, John P. (Albuquerque, NM)

    2002-01-01

    An attachment structure is disclosed for attaching a die to a supporting substrate without the use of adhesives or solder. The attachment structure, which can be formed by micromachining, functions purely mechanically in utilizing a plurality of shaped pillars (e.g. round, square or polygonal and solid, hollow or slotted) that are formed on one of the die or supporting substrate and which can be urged into contact with various types of mating structures including other pillars, a deformable layer or a plurality of receptacles that are formed on the other of the die or supporting substrate, thereby forming a friction bond that holds the die to the supporting substrate. The attachment structure can further include an alignment structure for precise positioning of the die and supporting substrate to facilitate mounting the die to the supporting substrate. The attachment structure has applications for mounting semiconductor die containing a microelectromechanical (MEM) device, a microsensor or an integrated circuit (IC), and can be used to form a multichip module. The attachment structure is particularly useful for mounting die containing released MEM devices since these devices are fragile and can otherwise be damaged or degraded by adhesive or solder mounting.

  12. Method for measuring lead concentrations in blood

    DOE Patents [OSTI]

    Nogar, Nicholas S. (Los Alamos, NM)

    2001-01-01

    Method for measuring lead concentrations in blood. The present invention includes the use of resonant laser ablation to analyze .ltoreq.1 .mu.L (or equivalent mass) samples of blood for lead content. A typical finger prick, for example, yields about 10 .mu.L. Solid samples may also readily be analyzed by resonant laser ablation. The sample is placed on a lead-free, electrically conducting substrate and irradiated with a single, focused laser beam which simultaneously vaporizes, atomizes, and resonantly ionizes an analyte of interest in a sample. The ions are then sorted, collected and detected using a mass spectrometer.

  13. Phase Transition and Electrical Properties of Ba0.7Ca0.3TiO3BiFeO3 Ceramics Cai-Xia Li,,

    E-Print Network [OSTI]

    Cao, Wenwu

    Phase Transition and Electrical Properties of Ba0.7Ca0.3TiO3­BiFeO3 Ceramics Cai-Xia Li,,§ Bin Yang, University Park, Pennsylvania 16802 Lead-free piezoelectric ceramics of (1 Ą x)Ba0.70 Ca0.30TiO3­x BiFeO3 [(1 Ą x)BCT­xBF, x = 0­0.065] have been prepared and investigated. The ceramics with x 0.06 have

  14. Ferroelectric and ferromagnetic properties in BaTiO{sub 3} thin films on Si (100)

    SciTech Connect (OSTI)

    Singamaneni, Srinivasa Rao, E-mail: ssingam@ncsu.edu; Prater, John T. [Materials Science Division, Army Research Office, Research Triangle Park, North Carolina 27709 (United States); Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Punugupati, Sandhyarani; Hunte, Frank; Narayan, Jagdish [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2014-09-07

    In this paper, we report on the epitaxial integration of room temperature lead-free ferroelectric BaTiO{sub 3} thin (?1050?nm) films on Si (100) substrates by pulsed laser deposition technique through a domain matching epitaxy paradigm. We employed MgO and TiN as buffer layers to create BaTiO{sub 3}/SrRuO{sub 3}/MgO/TiN/Si (100) heterostructures. C-axis oriented and cube-on-cube epitaxial BaTiO{sub 3} is formed on Si (100) as evidenced by the in-plane and out-of-plane x-ray diffraction, and transmission electron microscopy. X-ray photoemission spectroscopic measurements show that Ti is in 4(+) state. Polarization hysteresis measurements together with Raman spectroscopy and temperature-dependent x-ray diffraction confirm the room temperature ferroelectric nature of BaTiO{sub 3}. Furthermore, laser irradiation of BaTiO{sub 3} thin film is found to induce ferromagnetic-like behavior but affects adversely the ferroelectric characteristics. Laser irradiation induced ferromagnetic properties seem to originate from the creation of oxygen vacancies, whereas the pristine BaTiO{sub 3} shows diamagnetic behavior, as expected. This work has opened up the route for the integration of room temperature lead-free ferroelectric functional oxides on a silicon platform.

  15. Tests of prototype salt stripper system for IFR fuel cycle

    SciTech Connect (OSTI)

    Carls, E.L.; Blaskovitz, R.J.; Johnson, T.R. [Argonne National Lab., IL (United States); Ogata, T. [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

    1993-09-01

    One of the waste treatment steps for the on-site reprocessing of spent fuel from the Integral Fast Reactor fuel cycles is stripping of the electrolyte salt used in the electrorefining process. This involves the chemical reduction of the actinides and rare earth chlorides forming metals which then dissolve in a cadmium pool. To develop the equipment for this step, a prototype salt stripper system has been installed in an engineering scale argon-filled glovebox. Pumping trails were successful in transferring 90 kg of LiCl-KCl salt containing uranium and rare earth metal chlorides at 500{degree}C from an electrorefiner to the stripper vessel at a pumping rate of about 5 L/min. The freeze seal solder connectors which were used to join sections of the pump and transfer line performed well. Stripping tests have commenced employing an inverted cup charging device to introduce a Cd-15 wt % Li alloy reductant to the stripper vessel.

  16. Feed mechanism and method for feeding minute items

    DOE Patents [OSTI]

    Stringer, Timothy Kent; Yerganian, Simon Scott

    2012-11-06

    A feeding mechanism and method for feeding minute items, such as capacitors, resistors, or solder preforms. The mechanism is adapted to receive a plurality of the randomly-positioned and randomly-oriented extremely small or minute items, and to isolate, orient, and position the items in a specific repeatable pickup location wherefrom they may be removed for use by, for example, a computer-controlled automated assembly machine. The mechanism comprises a sliding shelf adapted to receive and support the items; a wiper arm adapted to achieve a single even layer of the items; and a pushing arm adapted to push the items into the pickup location. The mechanism can be adapted for providing the items with a more exact orientation, and can also be adapted for use in a liquid environment.

  17. Portable TXRF Spectrometer with 10{sup -11}g Detection Limit and Portable XRF Spectromicroscope with Sub-mm Spatial Resolution

    SciTech Connect (OSTI)

    Kunimura, Shinsuke; Hatakeyama, So; Sasaki, Nobuharu; Yamamoto, Takashi; Kawai, Jun

    2010-04-06

    A portable total reflection X-ray fluorescence (TXRF) spectrometer that we have developed is applied to trace elemental analysis of water solutions. Although a 5 W X-ray tube is used in the portable TXRF spectrometer, detection limits of several ppb are achieved for 3d transition metal elements and trace elements in a leaching solution of soils, a leaching solution of solder, and alcoholic beverages are detected. Portable X-ray fluorescence (XRF) spectromicroscopes with a 1 W X-ray tube and an 8 W X-ray tube are also presented. Using the portable XRF spectromicroscope with the 1 W X-ray tube, 93 ppm of Cr is detected with an about 700 {mu}m spatial resolution. Spatially resolved elemental analysis of a mug painted with blue, red, green, and white is performed using the two portable spectromicroscopes, and the difference in elemental composition at each paint is detected.

  18. Low thermal resistance power module assembly

    DOE Patents [OSTI]

    Hassani, Vahab (Denver, CO); Vlahinos, Andreas (Castle Rock, CO); Bharathan, Desikan (Arvada, CO)

    2007-03-13

    A power module assembly with low thermal resistance and enhanced heat dissipation to a cooling medium. The assembly includes a heat sink or spreader plate with passageways or openings for coolant that extend through the plate from a lower surface to an upper surface. A circuit substrate is provided and positioned on the spreader plate to cover the coolant passageways. The circuit substrate includes a bonding layer configured to extend about the periphery of each of the coolant passageways and is made up of a substantially nonporous material. The bonding layer may be solder material which bonds to the upper surface of the plate to provide a continuous seal around the upper edge of each opening in the plate. The assembly includes power modules mounted on the circuit substrate on a surface opposite the bonding layer. The power modules are positioned over or proximal to the coolant passageways.

  19. Module Experimental Process System Development Unit (MEPSDU). Quarterly report No. 1, November 26, 1980-February 28, 1981

    SciTech Connect (OSTI)

    Not Available

    1981-01-01

    The purpose of this program is to demonstrate the technical readiness of a cost-effective process sequence that has the potential for the production of flat plate photovoltaic modules which met the price goal in 1986 of 70 cents or less per Watt peak. During this initial program quarter, the efforts have included preparation and submission of the Work Breakdown Structure, the Baseline Cost Estimate and the Program Plan. The proposed process sequence was reviewed and laboratory verification experiments were conducted. The preliminary process includes the following features: semicrystalline silicon (10 cm x 10 cm) as the silicon input material, spray-on dopant diffusion source, Al paste BSF formation, spray-on AR coating, electroless Ni plate-solder dip Metallization, laser scribe edges, K and S tabbing and stringing machine, and laminated EVA modules.

  20. Capillary test specimen, system, and methods for in-situ visualization of capillary flow and fillet formation

    DOE Patents [OSTI]

    Hall, Aaron C. (Albuquerque, NM); Hosking, F. Michael (Albuquerque, NM),; Reece, Mark (Albuquerque, NM)

    2003-06-24

    A capillary test specimen, method, and system for visualizing and quantifying capillary flow of liquids under realistic conditions, including polymer underfilling, injection molding, soldering, brazing, and casting. The capillary test specimen simulates complex joint geometries and has an open cross-section to permit easy visual access from the side. A high-speed, high-magnification camera system records the location and shape of the moving liquid front in real-time, in-situ as it flows out of a source cavity, through an open capillary channel between two surfaces having a controlled capillary gap, and into an open fillet cavity, where it subsequently forms a fillet on free surfaces that have been configured to simulate realistic joint geometries. Electric resistance heating rapidly heats the test specimen, without using a furnace. Image-processing software analyzes the recorded images and calculates the velocity of the moving liquid front, fillet contact angles, and shape of the fillet's meniscus, among other parameters.

  1. Thin-film chip-to-substrate interconnect and methods for making same

    DOE Patents [OSTI]

    Tuckerman, David B. (Livermore, CA)

    1991-01-01

    Integrated circuit chips are electrically connected to a silica wafer interconnection substrate. Thin film wiring is fabricated down bevelled edges of the chips. A subtractive wire fabrication method uses a series of masks and etching steps to form wires in a metal layer. An additive method direct laser writes or deposits very thin metal lines which can then be plated up to form wires. A quasi-additive or subtractive/additive method forms a pattern of trenches to expose a metal surface which can nucleate subsequent electrolytic deposition of wires. Low inductance interconnections on a 25 micron pitch (1600 wires on a 1 cm square chip) can be produced. The thin film hybrid interconnect eliminates solder joints or welds, and minimizes the levels of metallization. Advantages include good electrical properties, very high wiring density, excellent backside contact, compactness, and high thermal and mechanical reliability.

  2. Electric lamp, base for use therewith and method of assembling same

    DOE Patents [OSTI]

    Hough, Harold L. (Beverly, MA); English, George J. (Reading, MA); Chakrabarti, Kirti B. (Danvers, MA)

    1989-02-14

    An electric lamp including a reflector, at least one conductive ferrule located within a surface of the reflector and a lead-in conductor electrically connected to the ferrule and extending within the reflector. The lamp includes a base having an insulative (e.g., ceramic) cap located substantially about the ferrule, barrier means (e.g., ceramic fiber) located within the cap to define an open chamber substantially about the ferrule, an electrical conductor (e.g., wire) extending within the cap and electrically connected (e.g., silver soldered) to the ferrule, and sealing means (e.g., high temperature cement) located within the cap to provide a seal therefore. The barrier means serves to separate the sealing means from the open chamber about the ferrule such that the heat generated by the ferrule can be vented through spaced apertures located within the cap's side wall. A method of assembling a base on an electric lamp is also provided.

  3. Method for fabricating fan-fold shielded electrical leads

    DOE Patents [OSTI]

    Rohatgi, R.R.; Cowan, T.E.

    1994-12-27

    Fan-folded electrical leads made from copper cladded Kapton, for example, with the copper cladding on one side serving as a ground plane and the copper cladding on the other side being etched to form the leads. The Kapton is fan folded with the leads located at the bottom of the fan-folds. Electrical connections are made by partially opening the folds of the fan and soldering, for example, the connections directly to the ground plane and/or the lead. The fan folded arrangement produces a number of advantages, such as electrically shielding the leads from the environment, is totally non-magnetic, and has a very low thermal conductivity, while being easy to fabricate. 3 figures.

  4. Fan-fold shielded electrical leads

    DOE Patents [OSTI]

    Rohatgi, R.R.; Cowan, T.E.

    1996-06-11

    Disclosed are fan-folded electrical leads made from copper cladded Kapton, for example, with the copper cladding on one side serving as a ground plane and the copper cladding on the other side being etched to form the leads. The Kapton is fan folded with the leads located at the bottom of the fan-folds. Electrical connections are made by partially opening the folds of the fan and soldering, for example, the connections directly to the ground plane and/or the lead. The fan folded arrangement produces a number of advantages, such as electrically shielding the leads from the environment, is totally non-magnetic, and has a very low thermal conductivity, while being easy to fabricate. 3 figs.

  5. Boron-copper neutron absorbing material and method of preparation

    DOE Patents [OSTI]

    Wiencek, Thomas C. (Bolingbrook, IL); Domagala, Robert F. (Indian Head Park, IL); Thresh, Henry (Palos Hts., IL)

    1991-01-01

    A composite, copper clad neutron absorbing material is comprised of copper powder and boron powder enriched with boron 10. The boron 10 content can reach over 30 percent by volume, permitting a very high level of neutron absorption. The copper clad product is also capable of being reduced to a thickness of 0.05 to 0.06 inches and curved to a radius of 2 to 3 inches, and can resist temperatures of 900.degree. C. A method of preparing the material includes the steps of compacting a boron-copper powder mixture and placing it in a copper cladding, restraining the clad assembly in a steel frame while it is hot rolled at 900.degree. C. with cross rolling, and removing the steel frame and further rolling the clad assembly at 650.degree. C. An additional sheet of copper can be soldered onto the clad assembly so that the finished sheet can be cold formed into curved shapes.

  6. Feed mechanism and method for feeding minute items

    DOE Patents [OSTI]

    Stringer, Timothy Kent (Bucyrus, KS); Yerganian, Simon Scott (Lee's Summit, MO)

    2009-10-20

    A feeding mechanism and method for feeding minute items, such as capacitors, resistors, or solder preforms. The mechanism is adapted to receive a plurality of the randomly-positioned and randomly-oriented extremely small or minute items, and to isolate, orient, and position one or more of the items in a specific repeatable pickup location wherefrom they may be removed for use by, for example, a computer-controlled automated assembly machine. The mechanism comprises a sliding shelf adapted to receive and support the items; a wiper arm adapted to achieve a single even layer of the items; and a pushing arm adapted to push the items into the pickup location. The mechanism can be adapted for providing the items with a more exact orientation, and can also be adapted for use in a liquid environment.

  7. Release Resistant Electrical Interconnections For Mems Devices

    DOE Patents [OSTI]

    Peterson, Kenneth A. (Albuquerque, NM); Garrett, Stephen E. (Albuquerque, NM); Reber, Cathleen A. (Corrales, NM)

    2005-02-22

    A release resistant electrical interconnection comprising a gold-based electrical conductor compression bonded directly to a highly-doped polysilicon bonding pad in a MEMS, IMEMS, or MOEMS device, without using any intermediate layers of aluminum, titanium, solder, or conductive adhesive disposed in-between the conductor and polysilicon pad. After the initial compression bond has been formed, subsequent heat treatment of the joint above 363 C creates a liquid eutectic phase at the bondline comprising gold plus approximately 3 wt % silicon, which, upon re-solidification, significantly improves the bond strength by reforming and enhancing the initial bond. This type of electrical interconnection is resistant to chemical attack from acids used for releasing MEMS elements (HF, HCL), thereby enabling the use of a "package-first, release-second" sequence for fabricating MEMS devices. Likewise, the bond strength of an Au--Ge compression bond may be increased by forming a transient liquid eutectic phase comprising Au-12 wt % Ge.

  8. Method for fabricating fan-fold shielded electrical leads

    DOE Patents [OSTI]

    Rohatgi, Rajeev R. (Mountain View, CA); Cowan, Thomas E. (Livermore, CA)

    1994-01-01

    Fan-folded electrical leads made from copper cladded Kapton, for example, with the copper cladding on one side serving as a ground plane and the copper cladding on the other side being etched to form the leads. The Kapton is fan folded with the leads located at the bottom of the fan-folds. Electrical connections are made by partially opening the folds of the fan and soldering, for example, the connections directly to the ground plane and/or the lead. The fan folded arrangement produces a number of advantages, such as electrically shielding the leads from the environment, is totally non-magnetic, and has a very low thermal conductivity, while being easy to fabricate.

  9. Fan-fold shielded electrical leads

    DOE Patents [OSTI]

    Rohatgi, Rajeev R. (Mountain View, CA); Cowan, Thomas E. (Livermore, CA)

    1996-01-01

    Fan-folded electrical leads made from copper cladded Kapton, for example, with the copper cladding on one side serving as a ground plane and the copper cladding on the other side being etched to form the leads. The Kapton is fan folded with the leads located at the bottom of the fan-folds. Electrical connections are made by partially opening the folds of the fan and soldering, for example, the connections directly to the ground plane and/or the lead. The fan folded arrangement produces a number of advantages, such as electrically shielding the leads from the environment, is totally non-magnetic, and has a very low thermal conductivity, while being easy to fabricate.

  10. Lead-based paint and lead-containing materials: The impact of recent EPA and OSHA regulations on maintenance and construction

    SciTech Connect (OSTI)

    Staker, R.D.; Scheffius, F.R.

    1998-07-01

    Over the past several years a number of new federal environmental, health, and safety regulations have been established which address various types of lead containing materials such as lead used in solder and lead-based paint. The regulations pertain to the use, removal, disposal, and handling of lead-containing materials during maintenance activities, renovation activities, and new construction. This paper will present a review of these new regulations, the impact on and applicability to maintenance and construction activities, and the risks to human health and environment. Examples will be used to illustrate the concepts discussed. This paper should be of particular interest to electric power senior managers, plant managers, environmental managers, and environmental staff.

  11. ES&H development activities for the W89 warhead

    SciTech Connect (OSTI)

    Pretzel, C.W.

    1995-08-01

    Environmental, Safety and Health (ES&H) issues became an important design consideration during the development of the W89 warhead for the SRAM 11 (Short-Range Attack Missile) missile. An action plan was developed to handle these issues at all the production agencies and at both the system and the component level. The main thrust was in the area of solvent substitution, in particular for solder flux removal. The cleaner d-limonene followed by an isopropyl alcohol rinse was selected for applications were the traditional cleaners were 1,1,1 trichloroethane or trichloroethylene. Compatibility testing rather than efficacy testing dominated the development effort. In addition to other solvent substitution applications, organic materials that were free of toluene diisocynate (TDI), and methylene dianiline (MDA) were explored for use in the W89.

  12. Metallurgical characterization of brass objects from the Akko 1 shipwreck, Israel

    SciTech Connect (OSTI)

    Ashkenazi, D., E-mail: dana@eng.tau.ac.il [Faculty of Engineering, Tel Aviv University, Ramat Aviv 69978 (Israel); Cvikel, D. [Leon Recanati Institute for Maritime Studies, University of Haifa, 31905 (Israel); Stern, A. [Department of Materials Engineering, Ben-Gurion University of the Negev, Beer Sheva 84105 (Israel); Klein, S. [Institut für Geowissenschaften, Facheinheit Mineralogie, J. W. Goethe Universität, Altenhöferallee 1, D-60438 Frankfurt am Main (Germany); Kahanov, Y. [Leon Recanati Institute for Maritime Studies, University of Haifa, 31905 (Israel)

    2014-06-01

    The Akko 1 shipwreck was a small Egyptian armed vessel or auxiliary naval brig built in the eastern Mediterranean at the beginning of the 19th century. During the underwater excavations, about 230 brass hook-and-eye closures were found, mainly in the bow area. In addition, 158 brass cases were found, mainly between midships and the aft extremity of the shipwreck. Metallurgical non-destructive and destructive characterizations of selected items were performed, including radiographic testing, XRF, lead isotope analysis, optical microscopy, SEM–EDS and microhardness tests. The hook-and-eye closures and the cases were both found to be made of binary copper–zinc alloy (about 30 wt.% zinc). While the brass cases were made from rolled sheets, hand-made using simple tools, and joined by tin–lead soldering material, the brass hook-and-eye closures were hand-made from drawn brass wire, and manufactured from commercial drawn brass bars by a cold-working process. The lead isotope analyses suggest different provenances of the raw materials used for making the brass objects, thus the different origins of the ores may hint that the brass wire and sheet were imported to the workshops in which the objects were manufactured. - Highlights: • Brass cases and hook-and-eye closures were retrieved from the Akko 1 shipwreck. • Both types of objects were made of binary copper–zinc alloy (about 30 wt.% zinc). • The cases were hand-made from rolled sheets and joined by tin–lead soldering. • Hook-and-eye closures were made from drawn brass wire manufactured by cold-working. • Lead isotope analyses suggest that the origins of the raw material were diverse.

  13. Materials Compatibility and Aging for Flux and Cleaner Combinations.

    SciTech Connect (OSTI)

    Archuleta, Kim; Piatt, Rochelle

    2015-01-01

    A materials study of high reliability electronics cleaning is presented here. In Phase 1, mixed type substrates underwent a condensed contaminants application to view a worst- case scenario for unremoved flux with cleaning agent residue for parts in a silicone oil filled environment. In Phase 2, fluxes applied to copper coupons and to printed wiring boards underwent gentle cleaning then accelerated aging in air at 65% humidity and 30 O C. Both sets were aged for 4 weeks. Contaminants were no-clean (ORL0), water soluble (ORH1 liquid and ORH0 paste), and rosin (RMA; ROL0) fluxes. Defluxing agents were water, solvents, and engineered aqueous defluxers. In the first phase, coupons had flux applied and heated, then were placed in vials of oil with a small amount of cleaning agent and additional coupons. In the second phase, pairs of copper coupons and PWB were hand soldered by application of each flux, using tin-lead solder in a strip across the coupon or a set of test components on the PWB. One of each pair was cleaned in each cleaning agent, the first with a typical clean, and the second with a brief clean. Ionic contamination residue was measured before accelerated aging. After aging, substrates were removed and a visual record of coupon damage made, from which a subjective rank was applied for comparison between the various flux and defluxer combinations; more corrosion equated to higher rank. The ORH1 water soluble flux resulted in the highest ranking in both phases, the RMA flux the least. For the first phase, in which flux and defluxer remained on coupons, the aqueous defluxers led to worse corrosion. The vapor phase cleaning agents resulted in the highest ranking in the second phase, in which there was no physical cleaning. Further study of cleaning and rinsing parameters will be required.

  14. Predicted thermal performance of triple vacuum glazing

    SciTech Connect (OSTI)

    Fang, Yueping; Hyde, Trevor J.; Hewitt, Neil

    2010-12-15

    The simulated triple vacuum glazing (TVG) consists of three 4 mm thick glass panes with two vacuum gaps, with each internal glass surface coated with a low-emittance coating with an emittance of 0.03. The two vacuum gaps are sealed by an indium based sealant and separated by a stainless steel pillar array with a height of 0.12 mm and a pillar diameter of 0.3 mm spaced at 25 mm. The thermal transmission at the centre-of-glazing area of the TVG was predicted to be 0.26 W m{sup -2} K{sup -1}. The simulation results show that although the thermal conductivity of solder glass (1 W m{sup -1} K{sup -1}) and indium (83.7 W m{sup -1} K{sup -1}) are very different, the difference in thermal transmission of TVGs resulting from the use of an indium and a solder glass edge seal was 0.01 W m{sup -2} K{sup -1}. This is because the edge seal is so thin (0.12 mm), consequently there is a negligible temperature drop across it irrespective of the material that the seal is made from relative to the total temperature difference across the glazing. The results also show that there is a relatively large increase in the overall thermal conductance of glazings without a frame when the width of the indium edge seal is increased. Increasing the rebate depth in a solid wood frame decreased the heat transmission of the TVG. The overall heat transmission of the simulated 0.5 m by 0.5 m TVG was 32.6% greater than that of the 1 m by 1 m TVG, since heat conduction through the edge seal of the small glazing has a larger contribution to the total glazing heat transfer than that of the larger glazing system. (author)

  15. Reduced Coercive Field in BiFeO3 Thin Films through Domain Engineering

    SciTech Connect (OSTI)

    Shelke, Vilas K; Mazumdar, Dipanjan; Srinivasan, Dr. Gopalan; Jesse, Stephen; Kalinin, Sergei V; Baddorf, Arthur P; Gupta, Dr. Arunava

    2011-01-01

    The bismuth ferrite (BiFeO3) material offers a comprehensive package of multifunctionality. In addition to the multiferroic behavior, i.e. coexistence of electric and magnetic orderings,[1] it also exhibits photovoltaic effect, [2] metal-insulator transition,[3] electric modulation of conduction,[4] and terahertz radiation emission.[5] The possibility of joint control of electric, magnetic, and optical properties provides several degrees of freedom to design exotic devices. It is a green energy material in the sense that it is lead-free and energy-efficient due to cryogen-less functionality. Therefore, a wide variety of applications in terms of sensors, memories and spintronic devices are foreseen.[6] However, the incipient lower value of magneto-electric coupling has raised skepticism regarding its multiferroic capabilities and allied applications.[6] Nevertheless, the highest value of ferroelectric polarization (~ 100 C.cm-2) is very promising for next generation ferroelectric random access memory devices.

  16. Low temperature synthesis of bismuth ferrite nanoparticles by a ferrioxalate precursor method

    SciTech Connect (OSTI)

    Ghosh, Sushmita [Central Glass and Ceramic Research Institute, 196 Raja S.C. Mullick Road, Kolkata, West Bengal 700032 (India); Dasgupta, Subrata [Central Glass and Ceramic Research Institute, 196 Raja S.C. Mullick Road, Kolkata, West Bengal 700032 (India)]. E-mail: sdasgupta@cgcri.res.in; Sen, Amarnath [Central Glass and Ceramic Research Institute, 196 Raja S.C. Mullick Road, Kolkata, West Bengal 700032 (India); Maiti, Himadri Sekhar [Central Glass and Ceramic Research Institute, 196 Raja S.C. Mullick Road, Kolkata, West Bengal 700032 (India)

    2005-12-08

    The synthesis of bismuth ferrite by solid-state reaction of Bi{sub 2}O{sub 3} and Fe{sub 2}O{sub 3} results in the formation of multiphase products. Even coprecipitation followed by calcination leads to the formation of impurity phases. Here, we report the synthesis of magnetoelectric bismuth ferrite by a ferrioxalate precursor method. In this process, bismuth ferrite, synthesized through solutions of some specific salts led to the formation of phase pure (perovskite) nanocrystalline powder (11-22 nm as evident from X-ray diffraction analysis) at a temperature of 600 deg. C. The synthesized powders were characterized by X-ray diffractometry, thermogravimetry and differential thermal analysis, Fourier transformation infrared spectroscopy and scanning electron microscopy. The synthesis route is simple, energy saving and cost-effective. Such nanosized bismuth ferrite powder may have a potential application in making lead free piezoelectric materials for actuators as well as magnetoelectric sensors.

  17. Aging in the relaxor and ferroelectric state of Fe-doped (1-x)(Bi{sub 1/2}Na{sub 1/2})TiO?-xBaTiO? piezoelectric ceramics

    SciTech Connect (OSTI)

    Sapper, Eva; Dittmer, Robert; Rödel, Jürgen; Damjanovic, Dragan; Erdem, Emre; Keeble, David J.; Jo, Wook; Granzow, Torsten

    2014-09-14

    Aging of piezoelectric properties was investigated in lead-free (1–x)(Bi{sub 1/2}Na{sub 1/2})TiO?-xBaTiO? doped with 1at.% Fe. The relaxor character of the un-poled material prevents macroscopic aging effects, while in the field-induced ferroelectric phase aging phenomena are similar to those found in lead zirconate titanate or barium titanate. Most prominent aging effects are the development of an internal bias field and the decrease of switchable polarization. These effects are temperature activated, and can be explained in the framework of defect complex reorientation. This picture is further supported by electron paramagnetic resonance spectra indicating the existence of (Fe{sub Ti}´-V{sub O}{sup ••}){sup •} defect complexes in the Fe-doped material.

  18. Energy Saving Melting and Revert Reduction Technology: Improved Die Casting Process to Preserve the Life of the Inserts

    SciTech Connect (OSTI)

    David Schwam, PI; Xuejun Zhu, Sr. Research Associate

    2012-09-30

    The goal of this project was to study the combined effects of die design, proper internal cooling and efficient die lubricants on die life. The project targeted improvements in die casting insert life by: Optomized Die Design for Reduced Surface Temperature: The life of die casting dies is significantly shorter when the die is exposed to elevated temperature for significant periods of time. Any die operated under conditions leading to surface temperature in excess of 1050oF undergoes structural changes that reduce its strength. Optimized die design can improve die life significantly. This improvement can be accomplished by means of cooling lines, baffles and bubblers in the die. A key objective of the project was to establish criteria for the minimal distance of the cooling lines from the surface. This effort was supported with alloys and machining by BohlerUddeholm, Dunn Steel, HH Stark and Rex Buckeye. In plant testing and evaluation was conducted as in-kind cost share at St. Clair Die Casting. The Uddeholm Dievar steel evaluated in this program showed superior resistance to thermal fatigue resistance. Based on the experimental evidence, cooling lines could be placed as close as 0.5"Ā¯ from the surface. Die Life Extension by Optimized Die Lubrication: The life of die casting dies is affected by additions made to its surface with the proper lubricants. These lubricants will protect the surface from the considerable temperature peaks that occur when the molten melt enters the die. Dies will reach a significantly higher temperature without this lubricant being applied. The amount and type of the lubricant are critical variables in the die casting process. However, these lubricants must not corrode the die surface. This effort was supported with alloys and machining by BohlerUddeholm, Dunn Steel, HH Stark and Rex Buckeye. In plant testing and evaluation was conducted as in-kind cost share at St. Clair Die Casting. Chem- Trend participated in the program with die lubricants and technical support. Experiments conducted with these lubricants demonstrated good protection of the substrate steel. Graphite and boron nitride used as benchmarks are capable of completely eliminating soldering and washout. However, because of cost and environmental considerations these materials are not widely used in industry. The best water-based die lubricants evaluated in this program were capable of providing similar protection from soldering and washout. In addition to improved part quality and higher production rates, improving die casting processes to preserve the life of the inserts will result in energy savings and a reduction in environmental wastes. Improving die life by means of optimized cooling line placement, baffles and bubblers in the die will allow for reduced die temperatures during processing, saving energy associated with production. The utilization of optimized die lubricants will also reduce heat requirements in addition to reducing waste associated with soldering and washout. This new technology was predicted to result in an average energy savings of 1.1 trillion BTU's/year over a 10 year period. Current (2012) annual energy saving estimates, based on commercial introduction in 2010, a market penetration of 70% by 2020 is 1.26 trillion BTU's/year. Along with these energy savings, reduction of scrap and improvement in casting yield will result in a reduction of the environmental emissions associated with the melting and pouring of the metal which will be saved as a result of this technology. The average annual estimate of CO2 reduction per year through 2020 is 0.025 Million Metric Tons of Carbon Equivalent (MM TCE).

  19. Robust hermetic packaging techniques for MEMS integrated microsystems.

    SciTech Connect (OSTI)

    Chae, Junseok (University of Michigan); Stark, Brian H. (University of Michigan); Kuo, Andrew (University of Michigan); Oliver, Andrew David; Najafi, Khalil (University of Michigan)

    2005-03-01

    This work is the result of a Sandia National Laboratories LDRD funded fellowship at the University of Michigan. Although, guidance and suggestions were offered by Sandia, the work contained here is primarily the work of Brian H. Stark, and his advisor, Professor Khalil Najafi. Junseok Chae, Andrew Kuo, and their coworkers at the University of Michigan helped to record some of the data. The following is an abstract of their work. We have developed a vacuum packaging technology using a thick nickel film to seal MEMS structures at the wafer level. The package is fabricated in a three-mask process by electroplating a 40 micro-meter thick nickel film over an 8 micro-meter sacrificial photoresist that is removed prior to package sealing. Implementation of electrical feedthroughs in this process requires no planarization. The large release channel enables an 800x800 micro-meter package to be released in less than three hours. Several mechanisms, based upon localized melting and lead/tin solder bumping, for sealing the release channel have been investigated. We have also developed Pirani gauges, integrated with this package, which can be used to establish the hermeticity of the different sealing technologies. They have measured a sealing pressure of approximately 1.5 Torr. Our work differs from previous Pirani gauges in that we utilize a novel doubly anchored structure that stiffens the structural membrane while not substantially degrading performance in order to measure fine leak rates.

  20. Investigation of proposed process sequence for the array automated assembly task. Phase I and II. Final report, October 1, 1977-June 30, 1980

    SciTech Connect (OSTI)

    Mardesich, N.; Garcia, A.; Eskenas, K.

    1980-08-01

    A selected process sequence for the low cost fabrication of photovoltaic modules was defined during this contract. Each part of the process sequence was looked at regarding its contribution to the overall dollars per watt cost. During the course of the research done, some of the initially included processes were dropped due to technological deficiencies. The printed dielectric diffusion mask, codiffusion of the n+ and p+ regions, wraparound front contacts and retention of the diffusion oxide for use as an AR coating were all the processes that were removed for this reason. Other process steps were retained to achieve the desired overall cost and efficiency. Square wafers, a polymeric spin-on PX-10 diffusion source, a p+ back surface field and silver front contacts are all processes that have been recommended for use in this program. The printed silver solderable pad for making contact to the aluminum back was replaced by an ultrasonically applied tin-zinc pad. Also, the texturized front surface was dropped as inappropriate for the sheet silicon likely to be available in 1986. Progress has also been made on the process sequence for module fabrication. A shift from bonding with a conformal coating to laminating with ethylene vinyl acetate and a glass superstrate is recommended for further module fabrication. The finalized process sequence is described.

  1. Laser-induced breakdown spectroscopy in industrial and security applications

    SciTech Connect (OSTI)

    Bol'shakov, Alexander A.; Yoo, Jong H.; Liu Chunyi; Plumer, John R.; Russo, Richard E.

    2010-05-01

    Laser-induced breakdown spectroscopy (LIBS) offers rapid, localized chemical analysis of solid or liquid materials with high spatial resolution in lateral and depth profiling, without the need for sample preparation. Principal component analysis and partial least squares algorithms were applied to identify a variety of complex organic and inorganic samples. This work illustrates how LIBS analyzers can answer a multitude of real-world needs for rapid analysis, such as determination of lead in paint and children's toys, analysis of electronic and solder materials, quality control of fiberglass panels, discrimination of coffee beans from different vendors, and identification of generic versus brand-name drugs. Lateral and depth profiling was performed on children's toys and paint layers. Traditional one-element calibration or multivariate chemometric procedures were applied for elemental quantification, from single laser shot determination of metal traces at {approx}10 {mu}g/g to determination of halogens at 90 {mu}g/g using 50-shot spectral accumulation. The effectiveness of LIBS for security applications was demonstrated in the field by testing the 50-m standoff LIBS rasterizing detector.

  2. Low thermal resistance power module assembly

    DOE Patents [OSTI]

    Hassani, Vahab (Denver, CO); Vlahinos, Andreas (Castle Rock, CO); Bharathan, Desikan (Arvada, CO)

    2010-12-28

    A power module assembly (400) with low thermal resistance and enhanced heat dissipation to a cooling medium. The assembly includes a heat sink or spreader plate (410) with passageways or openings (414) for coolant that extend through the plate from a lower surface (411) to an upper surface (412). A circuit substrate (420) is provided and positioned on the spreader plate (410) to cover the coolant passageways. The circuit substrate (420) includes a bonding layer (422) configured to extend about the periphery of each of the coolant passageways and is made up of a substantially nonporous material. The bonding layer (422) may be solder material which bonds to the upper surface (412) of the plate to provide a continuous seal around the upper edge of each opening (414) in the plate. The assembly includes power modules (430) mounted on the circuit substrate (420) on a surface opposite the bonding layer (422). The power modules (430) are positioned over or proximal to the coolant passageways.

  3. Microchannel heat sink assembly

    DOE Patents [OSTI]

    Bonde, W.L.; Contolini, R.J.

    1992-03-24

    The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watertight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures. 13 figs.

  4. Evaluation of permanent die coatings to improve the wear resistance of die casting dies. Final project report, January 1, 1995--April 30, 1997

    SciTech Connect (OSTI)

    Shivpuri, R.

    1997-09-18

    Die Casting dies are subject to severe service conditions during the die casting operation. While these severe conditions are necessary to achieve high production rates, they cause the dies which are commonly made of H13 die steel, to suffer frequent failures. The major die failure mechanisms are erosion or washout, Heat checking, soldering and corrosion. Due to their geometrical complexity, die casting dies are very expensive (some dies cost over a million dollars), and thus a large number of parts have to be produced by a die, to justify this cost and leverage the advantages of the die casting process (high production rates, low manpower costs). A potential increase in the die service life, thus has a significant impact on the economics of the die; casting operation. There are many ways to extend die life: developing new wear resistant die materials, developing new surface treatments including coatings, improving heat treatment of existing H13 dies, using better lubricants that can protect the die material, or modifying the die geometry and process parameters to reduce the intensity of wear. Of these the use of coatings to improve the wear resistance of the die surface has shown a lot of promise. Consequently, use of coatings in the die casting industry and their wide use to decrease die wear can improve significantly the productivity of shop operations resulting in large savings in material and energy usage.

  5. Liquid cooled, linear focus solar cell receiver

    DOE Patents [OSTI]

    Kirpich, Aaron S. (Broomall, PA)

    1985-01-01

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  6. In situ visualization of metallurgical reactions in nanoscale Cu/Sn diffusion couples

    SciTech Connect (OSTI)

    Yin, Qiyue [State Univ. of New York at Binghamton, Binghamton, NY (United States); Stach, Eric A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gao, Fan [Univ. of Massachusetts, Lowell, MA (United States); Zhou, Guangwen [State Univ. of New York at Binghamton, Binghamton, NY (United States); Gu, Zhiyong [Univ. of Massachusetts, Lowell, MA (United States)

    2015-01-01

    The Cu–Sn metallurgical soldering reaction in two-segmented Cu–Sn nanowires is visualized by in-situ transmission electron microscopy. By varying the relative lengths of Cu and Sn segments, we show that the metallurgical reaction starts at ~ 200 ° with the formation of a Cu–Sn solid solution for the Sn/Cu length ratio smaller than 1:5 while the formation of Cu–Sn intermetallic compounds (IMCs) for larger Sn/Cu length ratios. Upon heating the nanowires up to ~ 500 °C, two phase transformation pathways occur, ?-Cu?Sn? ? ?-Cu?Sn ? ?-Cu??Sn?? for nanowires with a long Cu segment and ?-Cu?Sn? ? ?-Cu?Sn ? ?-Cu?Sn with a short Cu segment. The dynamic in situ TEM visualization of the evolution of Kirkendall voids demonstrates that Cu diffuses faster both in Sn and IMCs than that of Sn in Cu? and IMCs, which is the underlying cause of the dependence of the IMC formation and associated phase evolution on the relative lengths of the Cu and Sn segments.

  7. Liquid cooled, linear focus solar cell receiver

    DOE Patents [OSTI]

    Kirpich, A.S.

    1983-12-08

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  8. Microchannel heat sink assembly

    DOE Patents [OSTI]

    Bonde, Wayne L. (Livermore, CA); Contolini, Robert J. (Pleasanton, CA)

    1992-01-01

    The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watetight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures.

  9. Low cost impulse compatible wideband antenna

    DOE Patents [OSTI]

    Rosenbury, Erwin T. (Livermore, CA); Burke, Gerald J. (Livermore, CA); Nelson, Scott D. (Tracy, CA); Stever, Robert D. (Lathrop, CA); Governo, George K. (Livermore, CA); Mullenhoff, Donald J. (Livermore, CA)

    2002-01-01

    An antenna apparatus and method for building the antenna is disclosed. Impulse signals travel through a feed point of the antenna with respect to a ground plane. A geometric fin structure is connected to the feed point, and through a termination resistance to the ground plane. A geometric ridge structure connected to the ground is positioned with respect to the fin in order to receive and radiate electromagnetic energy from the impulse signal at a predetermined impedance and over a predetermined set of frequencies. The fin and ridge can be either a wire or a planar surface. The fin and ridge may be disposed within a radiation cavity such as a horn. The radiation cavity is constructed of stamped and etched metal sheets bent and then soldered together. The fin and ridge are also formed from metal sheets or wires. The fin is attached to the feed point and then to the cavity through a termination resistance. The ridge is attached to the cavity and disposed with respect to the fin in order to achieve a particular set of antenna characteristics.

  10. Condensed Geometry

    E-Print Network [OSTI]

    Koustubh Kabe

    2010-02-10

    A spin (dependent) system treatment of gravity is adopted akin to the Sen-Ashtekar treatment. Time is reinserted into the space ``fluid'' at the quantum Level. This time - the Lorentzian one- is shown to be a vorticity of a ``fluid particle'' of the space and the effect is integrated over all the fluid particles to incorporate time in quantum gravity. This spacetime is viewed as a fluid of future light cones called the SU(2) dipoles of causality here in the paper.The future light cone structure is soldered internally to the new variables derived in this paper to accomodate a background free physics of quantum strings. The emergence of spacetime is shown to be a first order phase transition and that of separation of gravity from the unified field to be a second order phase transition. For the former case the cosmic time is chosen as the order parameter and for the latter case the angular momentum is chosen as the order parameter. A quantum blackhole thus nucleates at transition temperature which is the Planck temperature, $\\tau_{pl}$. Then the SU(2) dipoles enable interpretation of this black hole as a gravity gauge SL(2,$\\mathbb{C}$) dual of the U(1) gauge ferromagnetic phase. The usual QFT interpretation of this effect is the existence of locally Lorentzian spacetimes.

  11. Apparatus And Method Of Using Flexible Printed Circuit Board In Optical Transceiver Device

    DOE Patents [OSTI]

    Anderson, Gene R. (Albuquerque, NM); Armendariz, Marcelino G. (Albuquerque, NM); Bryan, Robert P. (Albuquerque, NM); Carson, Richard F. (Albuquerque, NM); Duckett, III, Edwin B. (Albuquerque, NM); McCormick, Frederick B. (Albuquerque, NM); Peterson, David W. (Sandia Park, NM); Peterson, Gary D. (Albuquerque, NM); Reysen, Bill H. (Lafayette, CO)

    2005-03-15

    This invention relates to a flexible printed circuit board that is used in connection with an optical transmitter, receiver or transceiver module. In one embodiment, the flexible printed circuit board has flexible metal layers in between flexible insulating layers, and the circuit board comprises: (1) a main body region orientated in a first direction having at least one electrical or optoelectronic device; (2) a plurality of electrical contact pads integrated into the main body region, where the electrical contact pads function to connect the flexible printed circuit board to an external environment; (3) a buckle region extending from one end of the main body region; and (4) a head region extending from one end of the buckle region, and where the head region is orientated so that it is at an angle relative to the direction of the main body region. The electrical contact pads may be ball grid arrays, solder balls or land-grid arrays, and they function to connect the circuit board to an external environment. A driver or amplifier chip may be adapted to the head region of the flexible printed circuit board. In another embodiment, a heat spreader passes along a surface of the head region of the flexible printed circuit board, and a window is formed in the head region of the flexible printed circuit board. Optoelectronic devices are adapted to the head spreader in such a manner that they are accessible through the window in the flexible printed circuit board.

  12. Attachment method for stacked integrated circuit (IC) chips

    DOE Patents [OSTI]

    Bernhardt, A.F.; Malba, V.

    1999-08-03

    An attachment method for stacked integrated circuit (IC) chips is disclosed. The method involves connecting stacked chips, such as DRAM memory chips, to each other and/or to a circuit board. Pads on the individual chips are rerouted to form pads on the side of the chip, after which the chips are stacked on top of each other whereby desired interconnections to other chips or a circuit board can be accomplished via the side-located pads. The pads on the side of a chip are connected to metal lines on a flexible plastic tape (flex) by anisotropically conductive adhesive (ACA). Metal lines on the flex are likewise connected to other pads on chips and/or to pads on a circuit board. In the case of a stack of DRAM chips, pads to corresponding address lines on the various chips may be connected to the same metal line on the flex to form an address bus. This method has the advantage of reducing the number of connections required to be made to the circuit board due to bussing; the flex can accommodate dimensional variation in the alignment of chips in the stack; bonding of the ACA is accomplished at low temperature and is otherwise simpler and less expensive than solder bonding; chips can be bonded to the ACA all at once if the sides of the chips are substantially coplanar, as in the case for stacks of identical chips, such as DRAM. 12 figs.

  13. Attachment method for stacked integrated circuit (IC) chips

    DOE Patents [OSTI]

    Bernhardt, Anthony F. (Berkeley, CA); Malba, Vincent (Livermore, CA)

    1999-01-01

    An attachment method for stacked integrated circuit (IC) chips. The method involves connecting stacked chips, such as DRAM memory chips, to each other and/or to a circuit board. Pads on the individual chips are rerouted to form pads on the side of the chip, after which the chips are stacked on top of each other whereby desired interconnections to other chips or a circuit board can be accomplished via the side-located pads. The pads on the side of a chip are connected to metal lines on a flexible plastic tape (flex) by anisotropically conductive adhesive (ACA). Metal lines on the flex are likewise connected to other pads on chips and/or to pads on a circuit board. In the case of a stack of DRAM chips, pads to corresponding address lines on the various chips may be connected to the same metal line on the flex to form an address bus. This method has the advantage of reducing the number of connections required to be made to the circuit board due to bussing; the flex can accommodate dimensional variation in the alignment of chips in the stack; bonding of the ACA is accomplished at low temperature and is otherwise simpler and less expensive than solder bonding; chips can be bonded to the ACA all at once if the sides of the chips are substantially coplanar, as in the case for stacks of identical chips, such as DRAM.

  14. In situ visualization of metallurgical reactions in nanoscale Cu/Sn diffusion couples

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

    Yin, Qiyue; Stach, Eric A.; Gao, Fan; Zhou, Guangwen; Gu, Zhiyong

    2015-02-10

    The Cu–Sn metallurgical soldering reaction in two-segmented Cu–Sn nanowires is visualized by in-situ transmission electron microscopy. By varying the relative lengths of Cu and Sn segments, we show that the metallurgical reaction starts at ~ 200 ° with the formation of a Cu–Sn solid solution for the Sn/Cu length ratio smaller than 1:5 while the formation of Cu–Sn intermetallic compounds (IMCs) for larger Sn/Cu length ratios. Upon heating the nanowires up to ~ 500 °C, two phase transformation pathways occur, ?-Cu?Sn? ? ?-Cu?Sn ? ?-Cu??Sn?? for nanowires with a long Cu segment and ?-Cu?Sn? ? ?-Cu?Sn ? ?-Cu?Sn with amore »short Cu segment. The dynamic in situ TEM visualization of the evolution of Kirkendall voids demonstrates that Cu diffuses faster both in Sn and IMCs than that of Sn in Cu? and IMCs, which is the underlying cause of the dependence of the IMC formation and associated phase evolution on the relative lengths of the Cu and Sn segments.« less

  15. High field Nb/sub 3/Sn Axicell insert coils for the Mirror Fusion Test Facility-B (MFTF-B) axicell configuration. Final report

    SciTech Connect (OSTI)

    Baldi, R.W.; Tatro, R.E.; Scanlan, R.M.; Agarwal, K.L.; Bailey, R.E.; Burgeson, J.E.; Kim, I.K.; Magnuson, G.D.; Mallett, B.D.; Pickering, J.L.

    1984-03-01

    Two 12-tesla superconducting insert coils are being designed by General Dynamics Convair Division for the axicell regions of MFTF-B for Lawrence Livermore National Laboratory. A major challenge of this project is to ensure that combined fabrication and operational strains induced in the conductor are within stringent limitations of the relatively brittle Nb/sub 3/Sn superconductor filaments. These coils are located in the axicell region of MFTF-B. They have a clear-bore diameter of 36.195cm (14.25 inches) and consist of 27 double pancakes (i.e., 54 pancakes per coil) would on an electrically insulated 304LN stainless steel/bobbin helium vessel. Each pancake has 57 turns separated by G-10CR insulation. The complete winding bundle has 4.6 million ampere-turns and uniform current density of 2007 A/cm/sup 2/. In conjunction with the other magnets in the system, they produce a 12-tesla central field and a 12.52-tesla peak field. A multifilamentary Nb/sub 3/Sn conductor was selected to meet these requirements. The conductor consists of a monolithic insert soldered into a copper stabilizer. Sufficient cross-sectional area and work-hardening of the copper stabilizer has been provided for the conductor to self-react the electromagnetic Lorentz force induced hoop stresses with normal operational tensile strains less than 0.07 percent.

  16. Innovative Seals for Solid Oxide Fuel Cells (SOFC)

    SciTech Connect (OSTI)

    Singh, Raj

    2008-06-30

    A functioning SOFC requires different type of seals such as metal-metal, metal-ceramic, and ceramic-ceramic. These seals must function at high temperatures between 600--900{sup o}C and in oxidizing and reducing environments of the fuels and air. Among the different type of seals, the metal-metal seals can be readily fabricated using metal joining, soldering, and brazing techniques. However, the metal-ceramic and ceramic-ceramic seals require significant research and development because the brittle nature of ceramics/glasses can lead to fracture and loss of seal integrity and functionality. Consequently, any seals involving ceramics/glasses require a significant attention and technology development for reliable SOFC operation. This final report is prepared to describe the progress made in the program on the needs, approaches, and performance of high temperature seals for SOFC. In particular, a new concept of self-healing glass seals is pursued for making seals between metal-ceramic material combinations, including some with a significant expansion mismatch.

  17. A novel planar ion funnel design for miniature ion optics

    SciTech Connect (OSTI)

    Chaudhary, A.; Amerom, Friso H. W. van; Short, R. T.

    2014-10-01

    The novel planar ion funnel (PIF) design presented in this article emphasizes simple fabrication, assembly, and operation, making it amenable to extreme miniaturization. Simulations performed in SIMION 8.0 indicate that ion focusing can be achieved by using a gradient of electrostatic potentials on concentric metal rings in a plane. A prototype was fabricated on a 35 × 35 mm custom-designed printed circuit board (PCB) with a center hole for ions to pass through and a series of concentric circular metal rings of increasing diameter on the front side of the PCB. Metal vias on the PCB electrically connected each metal ring to a resistive potential divider that was soldered on the back of the PCB. The PIF was tested at 5.5 × 10?? Torr in a vacuum test setup that was equipped with a broad-beam ion source on the front and a micro channel plate (MCP) ion detector on the back of the PIF. The ion current recorded on the MCP anode during testing indicated a 23× increase in the ion transmission through the PIF when electric potentials were applied to the rings. These preliminary results demonstrate the functionality of a 2D ion funnel design with a much smaller footprint and simpler driving electronics than conventional 3D ion funnels. Future directions to improve the design and a possible micromachining approach to fabrication are discussed in the conclusions.

  18. Further Analysis of Accelerated Exposure Testing of Thin-Glass Mirror Matrix

    SciTech Connect (OSTI)

    Kennedy, C. E.; Terwilliger, K.; Jorgensen, G. J.

    2007-01-01

    Concentrating solar power (CSP) companies have deployed thin-glass mirrors produced by wet-silver processes on {approx}1-mmthick, relatively lightweight glass. These mirrors are bonded to metal substrates in commercial installations and have the confidence of the CSP industry. Initial hemispherical reflectance is {approx}93%-96%, and the cost is {approx}$16.1/m{sup 2}-$43.0/m{sup 2}. However, corrosion was observed in mirror elements of operational solar systems deployed outdoors for 2 years. National Renewable Energy Laboratory (NREL) Advanced Materials Team has been investigating this problem. First, it was noted that this corrosion is very similar to the corrosion bands and spots observed on small (45 mm x 67 mm) thin-glass mirrors laminated to metal substrates with several different types of adhesives and subjected to accelerated exposure testing (AET) at NREL. The corrosion appears as dark splotches in the center of the mirror, with a corresponding 5%-20% loss in reflectivity. Secondly, two significant changes in mirror manufacture have occurred in the wet-chemistry process because of environmental concerns. The first is the method of forming a copper-free reflective mirror, and the second is the use of lead-free paints. However, the copper-free process requires stringent quality control and the lead-free paints were developed for interior applications. A test matrix of 84 combinations of sample constructions (mirror type/backprotective paint/adhesive/substrate) was devised for AET as a designed experiment to identify the most-promising mirrors, paints, and adhesives for use with concentrator designs. Two types of accelerated exposure were used: an Atlas Ci5000 WeatherOmeter (CI5000) and a BlueM damp-heat chamber. Based on an analysis of variance (ANOVA), the various factors and interactions were modeled. These samples now have more than 36 months of accelerated exposure, and most samples have completed their test cycle. We will discuss the results of the final exposure testing of these mirror samples. Glass mirrors with copper back-layers and heavily leaded paints have been considered robust for outdoor use. However, the basic mirror composition of the new mirrors is radically different from that of historically durable solar mirrors, and the outdoor durability must be determined.

  19. Structure and ferroelectric studies of (Ba{sub 0.85}Ca{sub 0.15})(Ti{sub 0.9}Zr{sub 0.1})O{sub 3} piezoelectric ceramics

    SciTech Connect (OSTI)

    Venkata Ramana, E.; Mahajan, A.; Graēa, M.P.F.; Mendiratta, S.K.; Monteiro, J.M.; Valente, M.A.

    2013-10-15

    Graphical abstract: - Highlights: • (Ba{sub 0.85}Ca{sub 0.15})(Ti{sub 0.9}Zr{sub 0.1})O{sub 3} (BCTZO) ceramic was synthesized by the ceramic method. • In situ XRD and Raman spectra showed the phase transition of BCTZO around 360 K. • The ceramics showed a tunability of 82% at 40 kV cm{sup ?1} electric field. • BCTZO exhibited good quality factor of 111 at microwave frequencies. • Piezoforce microscopy studies indicated the switchability of ferroelectric domains. - Abstract: We have synthesized and studied the structural and ferroelectric properties of lead-free 0.5(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3}–0.5Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3} ceramics in the temperature region of its ferroelectric transition. The synthesized material showed high dielectric constant, low loss and good pyroelectric figure of merit. From the temperature dependent X-ray diffraction measurements, we determined the tricritical point to be in the temperature range of 303–400 K. The dielectric measurements indicate a diffuse ferroelectric phase transition (DPT) around 360 K in agreement with the X-ray measurements. We studied the evolution of Raman spectra with temperature to understand the nature of phase transition in BaTiO{sub 3} (BTO) and the BCTZO. The results indicates that the transition of ferroelectric–paraelectric state is not sharp as in the case of BTO and the polar state persists through the paraelectric state. In general, our study indicates that there are ferroelectric domains of nanometer size beyond the commonly defined transition temperature. The observation of local piezoelectric hysteresis loop indicated the existence of intrinsic ferroelectric property of the ceramic at the nanoscale. The ceramics exhibited electric field tunable dielectric properties with a tunability of 82% at an applied DC field of 40 kV cm{sup ?1}, low dielectric loss of 0.001 and room temperature pyroelectric coefficient of 6 × 10{sup ?8} C cm{sup ?2} K{sup ?1} and the detectivity of 1.9 × 10{sup ?8} C cm{sup ?1} J{sup ?1}; larger than those reported for other BaTiO{sub 3}-based materials. Overall, our results indicate that BCTZO ceramics with coexistence of rhombohedral–tetragonal phases is a promising candidate for lead-free ferroelectric applications.

  20. Diameter dependent thermoelectric properties of individual SnTe nanowires

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

    Xu, E. Z.; Li, Z.; Martinez, J. A.; Sinitsyn, N.; Htoon, H.; Li, Nan; Swartzentruber, B.; Hollingsworth, J. A.; Wang, Jian; Zhang, S. X.

    2015-01-15

    The lead-free compound tin telluride (SnTe) has recently been suggested to be a potentially promising thermoelectric material because of its similar electronic band structure as the well-known lead telluride. Here we report on the first thermoelectric study of individual single crystalline SnTe nanowires (NWs) with different diameters ranging from ~200 to ~1000 nm. Measurements of thermopower S, electrical conductivity ?, and thermal conductivity ? were carried out on the same nanowires over a temperature range of 25 - 300 K. While ? does not show a strong diameter dependence, the thermopower increases by a factor of 2 when the nanowiremore »diameter is decreased from 1000 nm to 200 nm. The thermal conductivities of the measured NWs are only about half of that of the bulk SnTe, which may arise from the enhanced phonon-grain boundary and phonon-defect scatterings. Temperature dependent figure-of-merit ZT was determined and the maximum value at room temperature is ~3 times higher than what was obtained in bulk samples of comparable carrier density.« less

  1. Direct observation of intrinsic piezoelectricity of Pb(Zr,Ti)O{sub 3} by time-resolved x-ray diffraction measurement using single-crystalline films

    SciTech Connect (OSTI)

    Fujisawa, Takashi; Ehara, Yoshitaka; Yasui, Shintaro; Kamo, Takafumi; Funakubo, Hiroshi; Yamada, Tomoaki; Sakata, Osami

    2014-07-07

    Lead zirconate titanate, Pb(Zr,Ti)O{sub 3} or PZT, is one of the most widely investigated ferroelectric and piezoelectric materials due to its superior properties. However, the intrinsic properties of PZT have not been directly measured due to the lack of fabrication of single crystals even though a basic understanding of intrinsic properties has been of interest developing lead-free piezoelectric materials. We demonstrated the direct observation of the intrinsic piezoelectric property by means of the detection of electric-field induced crystal lattice distortion of thick Pb(Zr{sub 0.35}Ti{sub 0.65})O{sub 3} single-crystalline films with single polar-axis orientation and negligible residual strain using the time-resolved X-ray diffraction (XRD) together with the polarization response. Consequently, the effective converse piezoelectric response was experimentally revealed; hence, the electrostrictive coefficient, which is the conversion coefficient between the electrical and mechanical response, was determined. The obtained effective electrostrictive coefficient was 5.2–6.3?×?10{sup ?2} m{sup 4}/C{sup 2}, which agrees with theoretical prediction.

  2. Effects of lithium doping on microstructure, electrical properties, and chemical bonds of sol-gel derived NKN thin films

    SciTech Connect (OSTI)

    Lin, Chun-Cheng; Chen, Chan-Ching; Weng, Chung-Ming; Chu, Sheng-Yuan; Tsai, Cheng-Che

    2015-02-28

    Highly (100/110) oriented lead-free Li{sub x}(Na{sub 0.5}K{sub 0.5}){sub 1?x}NbO{sub 3} (LNKN, x?=?0, 0.02, 0.04, and 0.06) thin films are fabricated on Pt/Ti/SiO{sub 2}/Si substrates via a sol-gel processing method. The lithium (Li) dopants modify the microstructure and chemical bonds of the LNKN films, and therefore improve their electrical properties. The optimal values of the remnant polarization (P{sub r}?=?14.3??C/cm{sup 2}), piezoelectric coefficient (d{sub 33}?=?48.1?pm/V), and leakage current (<10{sup ?5} A/cm{sup 2}) are obtained for a lithium addition of x?=?0.04 (i.e., 4 at.?%). The observation results suggest that the superior electrical properties are the result of an improved crystallization, a larger grain size, and a smoother surface morphology. It is shown that the ion transport mechanism is dominated by an Ohmic behavior under low electric fields and the Poole-Frenkel emission effect under high electric fields.

  3. Energy-Saving Melting and Revert Reduction Technology (E-SMARRT): Use of Laser Engineered Net Shaping for Rapid Manufacturing of Dies with Protective Coatings and Improved Thermal Management

    SciTech Connect (OSTI)

    Brevick, Jerald R.

    2014-06-13

    In the high pressure die casting process, molten metal is introduced into a die cavity at high pressure and velocity, enabling castings of thin wall section and complex geometry to be obtained. Traditional die materials have been hot work die steels, commonly H13. Manufacture of the dies involves machining the desired geometry from monolithic blocks of annealed tool steel, heat treating to desired hardness and toughness, and final machining, grinding and polishing. The die is fabricated with internal water cooling passages created by drilling. These materials and fabrication methods have been used for many years, however, there are limitations. Tool steels have relatively low thermal conductivity, and as a result, it takes time to remove the heat from the tool steel via the drilled internal water cooling passages. Furthermore, the low thermal conductivity generates large thermal gradients at the die cavity surfaces, which ultimately leads to thermal fatigue cracking on the surfaces of the die steel. The high die surface temperatures also promote the metallurgical bonding of the aluminum casting alloy to the surface of the die steel (soldering). In terms of process efficiency, these tooling limitations reduce the number of die castings that can be made per unit time by increasing cycle time required for cooling, and increasing downtime and cost to replace tooling which has failed either by soldering or by thermal fatigue cracking (heat checking). The objective of this research was to evaluate the feasibility of designing, fabricating, and testing high pressure die casting tooling having properties equivalent to H13 on the surface in contact with molten casting alloy - for high temperature and high velocity molten metal erosion resistance – but with the ability to conduct heat rapidly to interior water cooling passages. A layered bimetallic tool design was selected, and the design evaluated for thermal and mechanical performance via finite element analysis. H13 was retained as the exterior layer of the tooling, while commercially pure copper was chosen for the interior structure of the tooling. The tooling was fabricated by traditional machining of the copper substrate, and H13 powder was deposited on the copper via the Laser Engineered Net Shape (LENSTM) process. The H13 deposition layer was then final machined by traditional methods. Two tooling components were designed and fabricated; a thermal fatigue test specimen, and a core for a commercial aluminum high pressure die casting tool. The bimetallic thermal fatigue specimen demonstrated promising performance during testing, and the test results were used to improve the design and LENS TM deposition methods for subsequent manufacture of the commercial core. Results of the thermal finite element analysis for the thermal fatigue test specimen indicate that it has the ability to lose heat to the internal water cooling passages, and to external spray cooling, significantly faster than a monolithic H13 thermal fatigue sample. The commercial core is currently in the final stages of fabrication, and will be evaluated in an actual production environment at Shiloh Die casting. In this research, the feasibility of designing and fabricating copper/H13 bimetallic die casting tooling via LENS TM processing, for the purpose of improving die casting process efficiency, is demonstrated.

  4. Mechanical stabilization of BSCCO-2223 superconducting tapes

    SciTech Connect (OSTI)

    King, C.G.; Grey, D.A.; Mantone, A.

    1996-12-31

    A system to provide mechanical stabilization to high temperature BSCCO-2223 superconducting tape by laminating 0.081 mm thick, spring hard, copper foil to both sides with lead-tin eutectic solder has been successfully optimized. This system has been applied as a method to create a strong, windable composite from pure silver BSCCO tapes with a minimum of critical current (I{sub c}) degradation. The {open_quotes}as received{close_quotes} conductor is evaluated for physical consistency of width and thickness over the 3000 meters that were later strengthened, insulated and wound into a demonstration coil. Electrical degradation in the strengthened tape as a result of lamination was found to average 24 percent with a range from 4 to 51 percent. This was less than the degradation that would have occurred in an unstrengthened tape during subsequent insulation and coil winding processes. Additional work was performed to evaluate the mechanical properties of the strengthened tapes. The copper can double the ultimate tensile strength of the pure silver tapes. Additionally, pure silver and dispersion strengthened silver matrix tapes are laminated with 0.025 mm thick copper and 304 stainless steel foil to investigate minimization of the cross sectional area of the strengthening component. The stainless steel can increase the UTS of the pure silver tapes sixfold. Metallography is used to examine the laminate and the conductor. Mechanical properties and critical currents of these tapes are also reported both before and after strengthening. The I{sub c} is also measured as a function of strain on the laminated tapes.

  5. Inter-strand current sharing and ac loss measurements in superconducting YBCO Roebel cables

    SciTech Connect (OSTI)

    sumption, Mike; Majoros, Milan; Collings, E. W.; Van der Laan, D. C.

    2014-11-07

    A Roebel cable, one twist pitch long, was modified from its as-received state by soldering copper strips between the strands to provide inter-strand connections enabling current sharing. Various DC transport currents (representing different percentages of its critical current) were applied to a single strand of such a modified cable at 77 K in a liquid nitrogen bath. Simultaneous monitoring of I–V curves in different parts of the strand as well as in its interconnections with other strands was made using a number of sensitive Keithley nanovoltmeters in combination with a multichannel high-speed data acquisition card, all controlled via LabView software. Current sharing onset was observed at about 1.02 of strand Ic. At a strand current of 1.3Ic about 5% of the current was shared through the copper strip interconnections. A finite element method modeling was performed to estimate the inter-strand resistivities required to enable different levels of current sharing. The relative contributions of coupling and hysteretic magnetization (and loss) were compared, and for our cable and tape geometry, and at dB/dt=1 T s-1, and our inter-strand resistance of 0.77 m?, (enabling a current sharing of 5% at 1.3Ic ) the coupling component was 0.32% of the hysteretic component. However, inter-strand contact resistance values of 100–1000 times smaller (close to those of NbTi and Nb3Sn based accelerator cables) would make the coupling components comparable in size to the hysteretic components.

  6. Concentrated Solar Thermoelectric Power

    SciTech Connect (OSTI)

    Chen, Gang; Ren, Zhifeng

    2015-07-09

    The goal of this project is to demonstrate in the lab that solar thermoelectric generators (STEGs) can exceed 10% solar-to-electricity efficiency, and STEGs can be integrated with phase-change materials (PCM) for thermal storage, providing operation beyond daylight hours. This project achieved significant progress in many tasks necessary to achieving the overall project goals. An accurate Themoelectric Generator (TEG) model was developed, which included realistic treatment of contact materials, contact resistances and radiative losses. In terms of fabricating physical TEGs, high performance contact materials for skutterudite TE segments were developed, along with brazing and soldering methods to assemble segmented TEGs. Accurate measurement systems for determining device performance (in addition to just TE material performance) were built for this project and used to characterize our TEGs. From the optical components’ side, a spectrally selective cermet surface was developed with high solar absorptance and low thermal emittance, with thermal stability at high temperature. A measurement technique was also developed to determine absorptance and total hemispherical emittance at high temperature, and was used to characterize the fabricated spectrally selective surfaces. In addition, a novel reflective cavity was designed to reduce radiative absorber losses and achieve high receiver efficiency at low concentration ratios. A prototype cavity demonstrated that large reductions in radiative losses were possible through this technique. For the overall concentrating STEG system, a number of devices were fabricated and tested in a custom built test platform to characterize their efficiency performance. Additionally, testing was performed with integration of PCM thermal storage, and the storage time of the lab scale system was evaluated. Our latest testing results showed a STEG efficiency of 9.6%, indicating promising potential for high performance concentrated STEGs.

  7. Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Development of Surface Engineered Coating Systems for Aluminum Pressure Die Casting Dies: Towards a 'Smart' Die Coating

    SciTech Connect (OSTI)

    Dr. John J. Moore; Dr. Jianliang Lin,

    2012-07-31

    The main objective of this research program was to design and develop an optimal coating system that extends die life by minimizing premature die failure. In high-pressure aluminum die-casting, the die, core pins and inserts must withstand severe processing conditions. Many of the dies and tools in the industry are being coated to improve wear-resistance and decrease down-time for maintenance. However, thermal fatigue in metal itself can still be a major problem, especially since it often leads to catastrophic failure (i.e. die breakage) as opposed to a wear-based failure (parts begin to go out of tolerance). Tooling costs remain the largest portion of production costs for many of these parts, so the ability prevent catastrophic failures would be transformative for the manufacturing industry.The technology offers energy savings through reduced energy use in the die casting process from several factors, including increased life of the tools and dies, reuse of the dies and die components, reduction/elimination of lubricants, and reduced machine down time, and reduction of Al solder sticking on the die. The use of the optimized die coating system will also reduce environmental wastes and scrap parts. Current (2012) annual energy saving estimates, based on initial dissemination to the casting industry in 2010 and market penetration of 80% by 2020, is 3.1 trillion BTU's/year. The average annual estimate of CO2 reduction per year through 2020 is 0.63 Million Metric Tons of Carbon Equivalent (MM TCE).

  8. Design and calibration of a test facility for MLI thermal performance measurements below 80K. [Multilayer insulation (MLI)

    SciTech Connect (OSTI)

    Boroski, W.; Kunzelman, R.; Ruschman, M.; Schoo, C.

    1992-04-01

    The design geometry of the SSC dipole cryostat includes active thermal radiation shields operating at 80K and 20K respectively. Extensive measurements conducted in a Heat Leak Test Facility (HLTF) have been used to evaluate the thermal performance of candidate multilayer insulation (MLI) systems for the 80K thermal shield, with the present system design based upon those measurement results. With the 80K MLI geometry established, efforts have focused on measuring the performance of MLI systems near 20K. A redesign of the HLTF has produced a measurement facility capable of conducting measurements with the warm boundary fixed at 80K and the cold boundary variable from 10K to 50K. Removing the 80K shield permits measurements with a warm boundary at 300K. The 80K boundary consists of a copper shield thermally anchored to a liquid nitrogen reservoir. The cold boundary consists of a copper anchor plate whose temperature is varied through boil-off gas from a 500 liter helium supply dewar. A transfer line heat exchanger supplies the boil-off gas to the anchor plate at a constant and controlled rate. The gas, which serves as cooling gas, is routed through a copper cooling tube soldered into the anchor plate. Varying the cooling gas flow rate varies the amount of refrigeration supplied to the anchor plate, thereby determining the plate temperature. A resistance heater installed on the anchor plate is regulated by a cryogenic temperature controller to provide final temperature control. Heat leak values are measured using a heatmeter which senses heat flow as a temperature gradient across a fixed thermal impedance. Since the thermal conductivity of the thermal impedance changes with temperature, the heatmeter is calibrated at key cold boundary temperatures. Thus, the system is capable of obtaining measurement data under a variety of system conditions. 7 refs.

  9. Design and calibration of a test facility for MLI thermal performance measurements below 80K

    SciTech Connect (OSTI)

    Boroski, W.; Kunzelman, R.; Ruschman, M.; Schoo, C.

    1992-04-01

    The design geometry of the SSC dipole cryostat includes active thermal radiation shields operating at 80K and 20K respectively. Extensive measurements conducted in a Heat Leak Test Facility (HLTF) have been used to evaluate the thermal performance of candidate multilayer insulation (MLI) systems for the 80K thermal shield, with the present system design based upon those measurement results. With the 80K MLI geometry established, efforts have focused on measuring the performance of MLI systems near 20K. A redesign of the HLTF has produced a measurement facility capable of conducting measurements with the warm boundary fixed at 80K and the cold boundary variable from 10K to 50K. Removing the 80K shield permits measurements with a warm boundary at 300K. The 80K boundary consists of a copper shield thermally anchored to a liquid nitrogen reservoir. The cold boundary consists of a copper anchor plate whose temperature is varied through boil-off gas from a 500 liter helium supply dewar. A transfer line heat exchanger supplies the boil-off gas to the anchor plate at a constant and controlled rate. The gas, which serves as cooling gas, is routed through a copper cooling tube soldered into the anchor plate. Varying the cooling gas flow rate varies the amount of refrigeration supplied to the anchor plate, thereby determining the plate temperature. A resistance heater installed on the anchor plate is regulated by a cryogenic temperature controller to provide final temperature control. Heat leak values are measured using a heatmeter which senses heat flow as a temperature gradient across a fixed thermal impedance. Since the thermal conductivity of the thermal impedance changes with temperature, the heatmeter is calibrated at key cold boundary temperatures. Thus, the system is capable of obtaining measurement data under a variety of system conditions. 7 refs.

  10. Inter-strand current sharing and ac loss measurements in superconducting YBCO Roebel cables

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

    Majoros, M.; Sumption, M. D.; Collings, E. W.; Long, N. J.

    2015-04-08

    A Roebel cable, one twist pitch long, was modified from its as-received state by soldering copper strips between the strands to provide inter-strand connections enabling current sharing. Various DC transport currents (representing different percentages of its critical current) were applied to a single strand of such a modified cable at 77 K in a liquid nitrogen bath. Simultaneous monitoring of I–V curves in different parts of the strand as well as in its interconnections with other strands was made using a number of sensitive Keithley nanovoltmeters in combination with a multichannel high-speed data acquisition card, all controlled via LabView software.more »Current sharing onset was observed at about 1.02 of strand Ic. At a strand current of 1.3Ic about 5% of the current was shared through the copper strip interconnections. A finite element method modeling was performed to estimate the inter-strand resistivities required to enable different levels of current sharing. The relative contributions of coupling and hysteretic magnetization (and loss) were compared, and for our cable and tape geometry, and at dB/dt=1 T s-1, and our inter-strand resistance of 0.77 m?, (enabling a current sharing of 5% at 1.3Ic) the coupling component was 0.32% of the hysteretic component. However, inter-strand contact resistance values of 100–1000 times smaller (close to those of NbTi and Nb3Sn based accelerator cables) would make the coupling components comparable in size to the hysteretic components.« less

  11. Inter-strand current sharing and ac loss measurements in superconducting YBCO Roebel cables

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

    sumption, Mike; Majoros, Milan; Collings, E. W.; Van der Laan, D. C.

    2014-11-07

    A Roebel cable, one twist pitch long, was modified from its as-received state by soldering copper strips between the strands to provide inter-strand connections enabling current sharing. Various DC transport currents (representing different percentages of its critical current) were applied to a single strand of such a modified cable at 77 K in a liquid nitrogen bath. Simultaneous monitoring of I–V curves in different parts of the strand as well as in its interconnections with other strands was made using a number of sensitive Keithley nanovoltmeters in combination with a multichannel high-speed data acquisition card, all controlled via LabView software.more »Current sharing onset was observed at about 1.02 of strand Ic. At a strand current of 1.3Ic about 5% of the current was shared through the copper strip interconnections. A finite element method modeling was performed to estimate the inter-strand resistivities required to enable different levels of current sharing. The relative contributions of coupling and hysteretic magnetization (and loss) were compared, and for our cable and tape geometry, and at dB/dt=1 T s-1, and our inter-strand resistance of 0.77 m?, (enabling a current sharing of 5% at 1.3Ic ) the coupling component was 0.32% of the hysteretic component. However, inter-strand contact resistance values of 100–1000 times smaller (close to those of NbTi and Nb3Sn based accelerator cables) would make the coupling components comparable in size to the hysteretic components.« less

  12. SU-E-I-76: Matching Primary and Scattered X-Ray Spectra for Use in Calculating the Diagnostic Radiation Index of Protection

    SciTech Connect (OSTI)

    Pasciak, A [University of Tennessee Medical Center, Knoxville, TN (United States); Jones, A [MD Anderson Cancer Center, Houston, TX (United States); Wagner, L [UT Medical School, Houston, TX (United States)

    2014-06-01

    Purpose: Lightweight lead-free or lead-composite protective garments exploit k-edge interactions to attenuate scattered X-rays. Manufacturers specify the protective value of garments in terms of lead equivalence at a single kVp. This is inadequate, as the protection provided by such garments varies with radiation quality in different use conditions. We present a method for matching scattered X-ray spectra to primary X-ray spectra. The resulting primary spectra can be used to measure penetration through protective garments, and such measurements can be weighted and summed to determine a Diagnostic Radiation Index for Protection (DRIP). Methods: Scattered X-ray spectra from fluoroscopic procedures were modeled using Monte Carlo techniques in MCNP-X 2.7. Data on imaging geometry, operator position, patient size, and primary beam spectra were gathered from clinical fluoroscopy procedures. These data were used to generate scattered X-ray spectra resulting from procedural conditions. Technical factors, including kV and added filtration, that yielded primary X-ray spectra that optimally matched the generated scattered X-ray spectra were identified through numerical optimization using a sequential quadratic programming (SQP) algorithm. Results: The primary spectra generated with shape functions matched the relative flux in each bin of the scattered spectra within 5%, and half and quarter-value layers matched within 0.1%. The DRIP for protective garments can be determined by measuring the penetration through protective garments using the matched primary spectra, then calculating a weighted average according to the expected clinical use of the garment. The matched primary spectra are specified in terms of first and second half-value layers in aluminum and acrylic. Conclusion: Lead equivalence is inadequate for completely specifying the protective value of garments. Measuring penetration through a garment using full scatter conditions is very difficult. The primary spectra determined in this work allow for practical primary penetration measurements to be made with equipment readily available to clinical medical physicists.

  13. An evaluation of chemical screening test kits for lead in paint

    SciTech Connect (OSTI)

    Oglesby, L.S.

    1996-04-01

    The Residential Lead-Based Paint Hazard Reduction Act (Title X) requires abatement and management of lead-based paint. The purpose of this study was to evaluate three chemical screening test kits using materials and methods from one study and subjecting the results to the statistical analysis of another. The three kits were used to predict the presence of lead in paint at ten weight concentrations from 0.04 to 3.97%. Paint was applied to four wood boards yielding a sample size of 40. Four boards were painted with lead-free paint and used as blanks. All of the boards were tested with the three test kits by an untrained individual having no knowledge of the actual lead content. Sensitivity, specificity, and false positive and negative rates were calculated for the test kit results. The manufactures` detection limits, the observed sensitivity ranged from 1.00 to 0.80, specificity ranged from 1.00 to 0.42, false positive ranged from 0 to 58%, and false negatives ranged from 0 to 20%. At the 0.5% Federal threshold level, the observed sensitivity ranged from 1.00 to 0.94, specificity ranged from 1.00 to 0.5, false positives ranged from 0 to 11.1%, and false negatives ranged from 0 to 20%. The observed false positive and false negative rates for all three kits were found to be significantly lower than those reported in a previous study. These results indicate that the kits perform very well at the Federal threshold, with two of the kits having false negative rates below 12.5% and false positive rates of 3.13%. These results indicate that these two kits would probably be acceptable screening tests for lead in paint.

  14. Challenges in the Packaging of MEMS

    SciTech Connect (OSTI)

    Malshe, A.P.; Singh, S.B.; Eaton, W.P.; O'Neal, C.; Brown, W.D.; Miller, W.M.

    1999-03-26

    The packaging of Micro-Electro-Mechanical Systems (MEMS) is a field of great importance to anyone using or manufacturing sensors, consumer products, or military applications. Currently much work has been done in the design and fabrication of MEMS devices but insufficient research and few publications have been completed on the packaging of these devices. This is despite the fact that packaging is a very large percentage of the total cost of MEMS devices. The main difference between IC packaging and MEMS packaging is that MEMS packaging is almost always application specific and greatly affected by its environment and packaging techniques such as die handling, die attach processes, and lid sealing. Many of these aspects are directly related to the materials used in the packaging processes. MEMS devices that are functional in wafer form can be rendered inoperable after packaging. MEMS dies must be handled only from the chip sides so features on the top surface are not damaged. This eliminates most current die pick-and-place fixtures. Die attach materials are key to MEMS packaging. Using hard die attach solders can create high stresses in the MEMS devices, which can affect their operation greatly. Low-stress epoxies can be high-outgassing, which can also affect device performance. Also, a low modulus die attach can allow the die to move during ultrasonic wirebonding resulting to low wirebond strength. Another source of residual stress is the lid sealing process. Most MEMS based sensors and devices require a hermetically sealed package. This can be done by parallel seam welding the package lid, but at the cost of further induced stress on the die. Another issue of MEMS packaging is the media compatibility of the packaged device. MEMS unlike ICS often interface with their environment, which could be high pressure or corrosive. The main conclusion we can draw about MEMS packaging is that the package affects the performance and reliability of the MEMS devices. There is a gross lack of understanding between the package materials, induced stress, and the device performance. The material properties of these packaging materials are not well defined or understood. Modeling of these materials and processes is far from maturity. Current post-package yields are too low for commercial feasibility, and consumer operating environment reliability and compatibility are often difficult to simulate. With further understanding of the materials properties and behavior of the packaging materials, MEMS applications can be fully realized and integrated into countless commercial and military applications.