Strain-induced surface segregation and ordering in pseudomorphic metal-alloy overlayers

Journal Article · Thu Oct 15 00:00:00 EDT 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.36.6288· OSTI ID:6090862

Dodson, B W

The stability of pseudomorphic metal films on a substrate composed of a different and lattice-mismatched metal against strain relief through intermixing is studied via atomistic simulations. Interdiffusion and lattice relaxation of the initial pseudomorphic structure is treated using a Monte Carlo procedure in which the structural energy of the bimetallic system is obtained using the embedded-atom method. Pseudomorphic overlayers of Ag were placed on (100) substrates of Pt (4.3% mismatch) and of Au (0.25% mismatch). Upon annealing at 1000 K, the Ag alloys with both substrates through interdiffusion. The Ag forms a uniform solid solution with the Au substrate. However, the Ag is trapped near the Pt surface by formation of slightly disordered Pt/sub 3/Ag layers. This trapping of Ag near the Pt surface in the ordered Pt/sub 3/Ag phase is induced by the misfit strain of the interdiffusing overlayer.

• Research Organization: Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185-5800
• OSTI ID: 6090862
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 36:12
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GOLD
MIXING
SURFACE PROPERTIES
PLATINUM
SILVER
THIN FILMS
DIFFUSION
SEGREGATION
STRAINS
METALS
MONTE CARLO METHOD
ORDER-DISORDER TRANSFORMATIONS
RELAXATION
STABILITY
SUBSTRATES
ELEMENTS
FILMS
PHASE TRANSFORMATIONS
PLATINUM METALS
TRANSITION ELEMENTS
360104* - Metals & Alloys- Physical Properties