Fabrication of amorphous ni- si films with small temperature coefficient of resistance by new flash evaporating method

Abstract

Utilizing a heat treatment processes, Ni-Si thin films which have various resistivity and various and/or small temperature coefficients of resistance (TCR) can be fabricated by new flash evaporating equipment assembled in our laboratory. In relation to the increase of Si content in the film, the TCR of the as-deposited film increases negatively. By using heat treatment to stabilize it, the film's resistance decreases and its TCR shifts in a positive direction. These trends become more marked if the heat treatment is performed at high temperature for longer durations. Under optimal heat treatment conditions, samples with a range of resistivity from 250 to 3500 Μ Ω · cm and a small TCR can be obtained. By using Auger electron spectroscopy, we also clarify the composition change of the film's depth direction fabricated by this method is more uniform than that of direct evaporating method.