Low-temperature ion-beam mixing in metals

Journal Article · Fri Jan 01 04:00:00 EST 1988 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.37.38· OSTI ID:5742991

Kim, S; Nicolet, M; Averback, R S; Peak, D

A systematic study of ion-beam mixing of tracer impurities in thin metal films at low temperatures has been conducted. We have investigated the dependence of ion mixing on two matrix properties: atomic mass and cohesive energy. We have also studied the dependence of ion mixing on tracer impurity properties: its heat of mixing with the matrix and its thermal diffusivity in the matrix. The matrices investigated were thin films of C, Al, Ti, Fe, Ni, Cu, Mo, Ru, Ag, Hf, Ta, W, Pt, and Au. The tracer impurities, Al, Ti, Cr, Mn, Fe, Ni, Cu, Y, Nb, Mo, Ru, Ag, In, Sb, Hf, Ta, W, Pt, Au, and Bi, were deposited as less than or equal to15 A layers near the midplanes of the specimens. All the tracer and matrix elements, except C, were deposited sequentially, without breaking vacuum. The samples were irradiated with 300--1000-keV Kr ions to doses 10/sup 15/--10/sup 16/ ions/cm/sup 2/ at temperatures of 6 and/or 77 K. Most samples were analyzed at the irradiation temperature by He backscattering. A strong correlation between ion mixing and the matrix properties, atomic mass, and cohesive energy, was observed. A correlation between ion mixing and tracer impurity diffusion was also observed but not between ion mixing and the heat of mixing or relative mass of the impurity with the matrix. The results are interpreted within the framework of a thermal spike model of cascade diffusion.

• Research Organization: California Institute of Technology, Pasadena, California 91125
• OSTI ID: 5742991
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 37:1; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
BACKSCATTERING
BEAMS
CHARGED PARTICLES
DIFFUSION
ELEMENTS
ENERGY RANGE
FILMS
FLUIDS
GASES
HELIUM
IMPURITIES
ION BEAMS
IONS
KEV RANGE
KEV RANGE 100-1000
KRYPTON IONS
LOW TEMPERATURE
MASS
METALS
MIXING
NONMETALS
RARE GASES
SCATTERING
TRACE AMOUNTS
ULTRALOW TEMPERATURE