Electrical characterization of alloy thin films of VSi₂ and V₃Si

Abstract

In situ resistivity measurement was used to study the crystallization and the electrical conduction processes of V3Si and VSi2 thin films as a function of temperature. The films were deposited by dual-electron-beam coevaporation through metallic masks in a van der Pauw configuration onto oxidized silicon substrates. In the as-deposited state the alloy thin films were amorphous. For the electrical characterization of VSi2, silicon-rich specimens with a V:Si atomic ratio of 1:3 were used. The kinetics of crystallization are well described by an equation of the Johnson-Mehl-Avrami type. Measurements of the electrical resistivity ρ{variant} over a wide temperature range (2-1100 K) on samples preheated at a high temperature exhibit a similar behavior for both the vanadium silicides, i.e. ρ{variant} rises less rapidly with temperature T than the Bloch-Grüneisen theory predicts and seems to approach a saturation value at the higher temperatures. An empirical formula is used to obtain a best fit of the resistivity curves. Polycrystalline V3Si thin film became superconductive at 15 K with a residual resistivity ratio of 10.6. © 1986.