US3824082A - Process for preparing superconducting niobium-gallium alloy - Google Patents

Process for preparing superconducting niobium-gallium alloy Download PDF

Info

Publication number
US3824082A
US3824082A US00268805A US26880572A US3824082A US 3824082 A US3824082 A US 3824082A US 00268805 A US00268805 A US 00268805A US 26880572 A US26880572 A US 26880572A US 3824082 A US3824082 A US 3824082A
Authority
US
United States
Prior art keywords
niobium
alloy
gallium
layer
temperature
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00268805A
Other languages
English (en)
Inventor
L Vieland
A Wicklund
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
RCA Corp
Original Assignee
RCA Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by RCA Corp filed Critical RCA Corp
Priority to US00268805A priority Critical patent/US3824082A/en
Priority to NL7304879A priority patent/NL7304879A/xx
Priority to FR7318223A priority patent/FR2190610B1/fr
Priority to CA173,127A priority patent/CA995310A/en
Priority to GB2999173A priority patent/GB1409340A/en
Priority to DE2332835A priority patent/DE2332835A1/de
Priority to JP48074674A priority patent/JPS4943812A/ja
Application granted granted Critical
Publication of US3824082A publication Critical patent/US3824082A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/06—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of metallic material
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/02—Pretreatment of the material to be coated
    • C23C16/0272—Deposition of sub-layers, e.g. to promote the adhesion of the main coating
    • C23C16/0281—Deposition of sub-layers, e.g. to promote the adhesion of the main coating of metallic sub-layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N60/00—Superconducting devices
    • H10N60/01—Manufacture or treatment
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N60/00—Superconducting devices
    • H10N60/01—Manufacture or treatment
    • H10N60/0184—Manufacture or treatment of devices comprising intermetallic compounds of type A-15, e.g. Nb3Sn
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N60/00—Superconducting devices
    • H10N60/80—Constructional details
    • H10N60/85—Superconducting active materials
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00—Stock material or miscellaneous articles
    • Y10S428/922—Static electricity metal bleed-off metallic stock
    • Y10S428/9265—Special properties
    • Y10S428/93—Electric superconducting
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00—Stock material or miscellaneous articles
    • Y10S428/922—Static electricity metal bleed-off metallic stock
    • Y10S428/9335—Product by special process
    • Y10S428/938—Vapor deposition or gas diffusion
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S505/00—Superconductor technology: apparatus, material, process
    • Y10S505/80—Material per se process of making same
    • Y10S505/801—Composition
    • Y10S505/805—Alloy or metallic
    • Y10S505/806—Niobium base, Nb
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S505/00—Superconductor technology: apparatus, material, process
    • Y10S505/80—Material per se process of making same
    • Y10S505/812—Stock
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S505/00—Superconductor technology: apparatus, material, process
    • Y10S505/80—Material per se process of making same
    • Y10S505/815—Process of making per se
    • Y10S505/818—Coating
    • Y10S505/819—Vapor deposition
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49014—Superconductor
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12639—Adjacent, identical composition, components
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12806—Refractory [Group IVB, VB, or VIB] metal-base component
    • Y10T428/12819—Group VB metal-base component

Definitions

  • This invention relates to an improved method for preparing a niobium-gallium superconducting alloy having a high critical temperature, i.e., onsetof superconductivity (hereinafter designated T,,) by chemical vapor deposition.
  • T critical temperature
  • high T Nb Ga alloy can be prepared by a two-step chemical vapor deposition process whereby a high T Nb Ga alloy is grown at about 640- 700" C. on a layer of a lower T niobium-rich niobiumgallium alloy deposited on a substrate at higher temperatures.
  • FIG. 1 is a schematic representation of a reactor in which the process of the invention can be carried out.
  • suitable halides of niobium and gallium are thoroughly admixed in a reactor in suitable proportions so as to provide a fi-tungsten alloy when the halides are reduced, exposed to a reducing agent at.a first temperature above 700 0., preferably about 750 C. or higher, thereby depositing on a substrate positioned within the reactor a first layer of a niobium-rich B- 'tungstein niobium-gallium alloy, and then decreasing the temperature to about 700 C. or lower while decreasing the proportion of niobium halide to deposit a second, higher T layer of p-tungsten niobium-gallium alloy thereon.
  • -By niobium-rich fi-tungsten niobium-gallium alloy herein is meant an alloy which contains more than the stoichiometric amount required for any alloy conforming to the formula Nb Ga.
  • halide herein is meant to include bromides or chlorides but chlorides are readily formed and are preferred.
  • the chlorides can be formed conveniently by passing a chlorinating gas, such as chlorine or hydrogen chloride, over each of the metals separately in the desired proportions at the temperature of reaction in inlet tubes connected to the main reactor.
  • a chlorinating gas such as chlorine or hydrogen chloride
  • Niobium which is solid at all reaction temperatures herein, can be employed in the form of a finely divided powder or turnings to assure adequate contact with the chlorinating gas.
  • Gallium is, of course, molten at the present temperatures.
  • the chlorides initially rich in niobium, are fed to a suitable reactor in which they are thoroughly admixed.
  • a smallexcess of hydrogen chloride is preferably also added along with the metal chlorides to the reactor to guard against premature deposition or reaction, which would result in variation of the composition of the resultant deposited alloys.
  • the metal chloride stream is advanced through the reactor conveniently on an inert carrier gas, such as helium, argon and the like, to a reducing zone, which also contains the substrate.
  • an inert carrier gas such as helium, argon and the like
  • hydrogen is employed as the reducing agent, preferably preheated to the reaction temperature.
  • the substrate can be any solid substrate, such as metal, ceramic, high temperature glass, quartz and the like, and can have any desired shape, such as a plate or sheet, box, boat, wire and the like.
  • the initial layer deposited on the substrate is a ,B-tungsten phase, high niobium content alloy having a fairly low T on the order of 1315 K.
  • Deposition of this first layer is continued until a layer of about 3-5 microns in thickness has been deposited on the substrate.
  • This layer provides a base upon which the desired high T Nb Ga alloy can be grown and which inhibits the deposition of undesired Nb Ga
  • the temperature in the reaction zone is lowered to about 700 C. or less, suitably to between 640-700" C. but preferably to about 700 C.
  • the niobium concentration is also reduced so as to deposit an alloy conforming more closely to the formula Nb Ga, by limiting the proportion of the reactant hydrogen chloride feed stream to the niobium source to about 80-85% by weight.
  • the layer deposited on the substrate in the second step is a ,B-tungsten phase niobium-gallium alloy having a near stoichiometric composition conforming to the formula Nb Ga, having a high T generally between 19- 20 K. and having a narrow superconducting transition temperature. Deposition of this layer is continued until a layer of the desired thickness has been deposited on the substrate.
  • the substrate is then removed from the reaction vessel and cooled to room temperature. Preferably, however, it is maintained at about 700 C. while being flushed with an inert gas after the deposition is stopped to remove any hydrogen which may be incorporated into the lattice of the deposited alloy.
  • the process of the invention can be adapted to a semi-continuous or a continuous process by providing a reactor with separate heating and reducing zones and means to advance the substrate from one zone to another, as will be readily apparent to one skilled in the art.
  • Example 1 A quartz reactor fitted with a Y-shaped inlet tube 11 having an inverted opening 12 facing the rear wall 13 of the reactor 10, a hydrogen inlet tube 14, a flush gas inlet tube 1.5 and exhaust gas tube 16 was flushed with helium gas. The temperature of the heated zone 17 was brought to 750 C. A flow of 100 standard cubic centimeters per minute (hereinafter designated s.c.c.m.) of helium as a carrier gas was introduced through both quartz arms 18 and 19 of inlet tube 1.1 and through inlet tube 15. Arm 18 contained niobium turnings 20 and arm 19 con tained a quartz boat 21 filled with gallium. A hydrogen stream at 400 s.c.c.m. was introduced through hydrogen inlet tube 14.
  • s.c.c.m. 100 standard cubic centimeters per minute
  • the plate 23 had a second layer about 30 microns thick of a fl-tungsten niobiumgallium alloy having a T of be-
  • the procedure of Example 1 was followed except the second reaction temperature was reduced to 640 C.
  • the resultant second layer of B-tungsten niobium-gallium alloy had a T of between 19.6 and 19.9 K.
  • An article of manufacture which comprises a substrate, a first layer of a niobium-rich niobium-gallium alloy having a fl-tungsten phaseand having a critical temperature on thetorder of 13-15 Ktgand: a second; layer thereon of a niobium-gallium allo'yhaving a fl-tun-gsten phase and a high critical temperature aboveabout- 19"? K. which contains about one molecule of gallium' to three molecules of niobium.
  • a method of preparing a superconducting niobiumgallium alloy having a high critical" temperature which comprises depositing afirstlayer of a niobium-rich alloy of niobium-gallium in the fi-tungsten phase from amixture of halides of niobium and gallium at a temperature above 700 C. on a substrate and depositin-g thereona second alloy layer, diiferent from said firstlayer, from a mixture of halides of niobium and gallium at a temperature between about 640-700 C., said second alloy containing about one atom of gallium to three atoms of niobium.
  • a method of preparing a superconducting niobiumgallium alloy having a high critical temperature which comprises (a) passing hydrogen chloride over a source of niobium and a source of gallium at a temperature of above 700 C. so that the proportion of chlorides of niobium is about 95% by weight of the total chlorides of niobium and gallium produced, f (b) admixing the resultant chlorides of niobiumfa'rid gallium in the vapor phase at about 750 C., (c) depositing a first layer of a niobium-rich niobiumgallium alloy in the fi-tungsten phase on a substrate in a reducing atmosphere to a depth of 3-5 microns, (d) cooling the reaction zone to a temperature within a range between 640 and 700 C., v 5 p (e) adjusting the proportion of niobium chloridesto -85% by weight of the combined niobium chloride and gallium chloride
  • a method of preparing a superconducting niobiumlgallium alloy having a high critical temperature which comprises I (a) passing a hydrogen halide over a source of niobium and a source of gallium at a temperature of above 700 C. so that the proportion of halides of niobium is about by weight of the total halides of niobium and gallium produced,
  • step (a) is about 750 C.
  • step (c) is continued until a layer of about 3-5 microns in thickness has been deposited on the substrate.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Metallurgy (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Chemical Vapour Deposition (AREA)
  • Superconductor Devices And Manufacturing Methods Thereof (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)
US00268805A 1972-07-03 1972-07-03 Process for preparing superconducting niobium-gallium alloy Expired - Lifetime US3824082A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US00268805A US3824082A (en) 1972-07-03 1972-07-03 Process for preparing superconducting niobium-gallium alloy
NL7304879A NL7304879A (enrdf_load_stackoverflow) 1972-07-03 1973-04-09
FR7318223A FR2190610B1 (enrdf_load_stackoverflow) 1972-07-03 1973-05-18
CA173,127A CA995310A (en) 1972-07-03 1973-06-04 Superconducting niobium-gallium alloy
GB2999173A GB1409340A (en) 1972-07-03 1973-06-25 Superconducting niobium-gallium alloy
DE2332835A DE2332835A1 (de) 1972-07-03 1973-06-28 Supraleitende niob-gallium-legierung
JP48074674A JPS4943812A (enrdf_load_stackoverflow) 1972-07-03 1973-07-02

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00268805A US3824082A (en) 1972-07-03 1972-07-03 Process for preparing superconducting niobium-gallium alloy

Publications (1)

Publication Number Publication Date
US3824082A true US3824082A (en) 1974-07-16

Family

ID=23024562

Family Applications (1)

Application Number Title Priority Date Filing Date
US00268805A Expired - Lifetime US3824082A (en) 1972-07-03 1972-07-03 Process for preparing superconducting niobium-gallium alloy

Country Status (7)

Country Link
US (1) US3824082A (enrdf_load_stackoverflow)
JP (1) JPS4943812A (enrdf_load_stackoverflow)
CA (1) CA995310A (enrdf_load_stackoverflow)
DE (1) DE2332835A1 (enrdf_load_stackoverflow)
FR (1) FR2190610B1 (enrdf_load_stackoverflow)
GB (1) GB1409340A (enrdf_load_stackoverflow)
NL (1) NL7304879A (enrdf_load_stackoverflow)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4101731A (en) * 1976-08-20 1978-07-18 Airco, Inc. Composite multifilament superconductors
US4242419A (en) * 1977-12-29 1980-12-30 Bell Telephone Laboratories, Incorporated Epitaxial growth of superconductors such as Nb3 Ge superconductors

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60165338A (ja) * 1984-02-08 1985-08-28 Hitachi Ltd 化合物超電導体およびその製造法
DE3887846T2 (de) * 1987-06-16 1994-05-19 Kawasaki Steel Co Verfahren zur bildung von dünnfilmen aus supraleitenden oxyden.
DE19504754A1 (de) * 1995-02-03 1996-08-08 Univ Leipzig Photovoltaische und photoelektrische Bauteile

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4101731A (en) * 1976-08-20 1978-07-18 Airco, Inc. Composite multifilament superconductors
US4242419A (en) * 1977-12-29 1980-12-30 Bell Telephone Laboratories, Incorporated Epitaxial growth of superconductors such as Nb3 Ge superconductors

Also Published As

Publication number Publication date
NL7304879A (enrdf_load_stackoverflow) 1974-01-07
JPS4943812A (enrdf_load_stackoverflow) 1974-04-25
FR2190610A1 (enrdf_load_stackoverflow) 1974-02-01
GB1409340A (en) 1975-10-08
DE2332835A1 (de) 1974-01-24
FR2190610B1 (enrdf_load_stackoverflow) 1976-05-07
CA995310A (en) 1976-08-17

Similar Documents

Publication Publication Date Title
US4992305A (en) Chemical vapor deposition of transistion metals
US6063705A (en) Precursor chemistries for chemical vapor deposition of ruthenium and ruthenium oxide
US3771976A (en) Metal carbonitride-coated article and method of producing same
US5591483A (en) Process for the preparation of metal nitride coatings from single source precursors
Hartsough et al. The synthesis of low temperature phases by the CO-condensation of the elements: A new superconducting A15 compound, V3Al
US3824082A (en) Process for preparing superconducting niobium-gallium alloy
JPH083171A (ja) 付加物、該付加物の製造方法及び薄膜の製造方法
US4880670A (en) Chemical vapor deposition of Group IB metals
US4882206A (en) Chemical vapor deposition of group IIIB metals
US4005990A (en) Superconductors
US3637422A (en) Dispersion-hardened tungsten alloy
US3589927A (en) Chromising of ferrous metal substrates
US4054686A (en) Method for preparing high transition temperature Nb3 Ge superconductors
US4142947A (en) Electrodeposition of polycrystalline silicon from a molten fluoride bath and product
Klam et al. Chemical vapour deposition of silicon onto iron: influence of silicon vapour phase source on the composition and nature of the coating
CA1087040A (en) Chemical vapor deposition
US3200015A (en) Process for coating high temperature alloys
US3404998A (en) Method of metal plating aluminum alloys
US3703405A (en) Vapor deposition of rhenium and rhenium-tungsten alloy coatings
JPH0194613A (ja) 気相成長方法
JPS58110493A (ja) 黒鉛ウイスカ−の製造法
EP0240844B1 (en) Metalorganic vapor phase epitaxial growth of group ii-vi semiconductor materials
US3472694A (en) Deposition of crystalline niobium stannide
De Mattei et al. Conditions for stable growth of epitaxial GaP layers by molten salt electrodeposition
US4814203A (en) Vapor deposition of arsenic