Studying diffusion in multilayer thin-film structures on silicon by the contact melting technique

Abstract

Features of the contact melting in thin-film structures comprising an aluminum layer with a thickness of h ₁ = 5 μm and a metal (Ti, Ni, Mo) or semiconductor (Si, Ge) sublayer (h ₂ = 0.1 μm) on a single crystal silicon plate (h ₃ = 500 μm) have been studied. The contact melting was caused by single rectangular electric pulses with a current density of j < 9 × 10¹⁰ A/m² and a duration of τ = 100–1000 μs passing through the Al layer. The duration and rate of melting in the samples were determined using voltage waveforms measured by an oscillograph. A method has been developed based on an analysis of the mechanisms of contact interaction in the Al film—sublayer system (with allowance for experimental data on the time of sublayer dissolution in the Al film) for estimating the coefficients of mutiphase diffusion of the system components during the passage of a current pulse.