Deposition by glow discharge sputtering of thin epitaxial films of Ib–VIII alloys (AgPd, CuPd, CuRh)

Abstract

Thin films of CuRh, CuPd, and AgPd were deposited by glow discharge sputtering onto (100) magnesium oxide single crystals. The rhodium and palladium content ranged from 0% to 100% of precious metal and the film thickness was usually between 10 and 100 nm. The composition, epitaxial relationship, crystallinity, and phase diagram were investigated as a function of substrate temperature and target composition. A comparison of the three systems was realized. Conditions of epitaxy were determined for the pure metals and their alloys. The temperature of epitaxy of the alloys, even at very low precious metal concentrations, is close to that of the group VIII elements. The parallel epitaxial relationship between the deposit and the substrate is identical for the three systems, namely (001)[110]d∥(001)[110]s. Various techniques were used to characterize the deposits: grazing incidence x-ray diffraction, electron probe microanalysis, Auger electron spectroscopy, scanning Auger microscopy, pulse polarography, reflection high-energy electron diffraction, transmission high-energy electron diffraction, transmission electron microscopy, and inductively coupled plasma.