Effect of heavy dose implantations of B and C on the crystal structure and superconducting transition temperature of A-15 Nb/sub 3/Al

Journal Article · Sun Jan 15 04:00:00 EST 1984 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.333076· OSTI ID:5560442

Clapp, M T

The effect of ion implantation on metastable phase formation and superconducting transition temperature (T/sub c/) has been investigated. The particular alloys studied were Nb/sub 3/Al/sub 1-x/B/sub x/ and Nb/sub 3/Al/sub 1-x/C/sub x/. A-15 Nb/sub 3/Al was used as the substrate material. Large doses of B and C (up to 23 at.%) were implanted into Al depleted surfaces. A series of implantation energies and doses was chosen to maintain the (Al+B) and (Al+C) concentrations equal to 25 at. %. This is necessary for achieving high T/sub c/ materials. Auger analysis indicated that there was very good agreement between experimental and theoretical dopant profiles immediately after implantation. After annealing up to 900 /sup 0/C the B atoms showed very little redistribution; however the C atoms tended to migrate towards the surface. Structural analysis using a READ camera and a diffractometer indicated that the large doses of B and C had been implanted into the A-15 structure without affecting its stability; this A-15 phase remained stable up to 950 /sup 0/C. Implantation caused the lattice parameter of the A-15 phase to increase by 1%--2%. There was no increase in the superconducting transition temperature above that of the substrate (18 K). This work is consistent with other studies; implantation has successfully produced metastable phases; however implantation into A-15's has not increased their T/sub c/'s.

• Research Organization: Department of Mechanical Engineering, University of Massachusetts, Amherst, Massachusetts 01003
• DOE Contract Number: AC02-80ER10566
• OSTI ID: 5560442
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 55:2; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
360102 -- Metals & Alloys-- Structure & Phase Studies
360104 -- Metals & Alloys-- Physical Properties
656102 -- Solid State Physics-- Superconductivity-- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena-- (-1987)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOYS
ALUMINIUM ALLOYS
ANNEALING
AUGMENTATION
BETA-W LATTICES
BORON
BORON ADDITIONS
BORON ALLOYS
CAMERAS
CARBON
CARBON ADDITIONS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIFFRACTOMETERS
DOSE RATES
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
HEAT TREATMENTS
ION IMPLANTATION
LATTICE PARAMETERS
MEASURING INSTRUMENTS
METALLURGICAL EFFECTS
NIOBIUM ALLOYS
NONMETALS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SEMIMETALS
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
VERY HIGH TEMPERATURE