Formation of the nickel-platinum alloy silicide Schottky barriers

Abstract

We propose a new technique for the Schottky barrier formation that involves magnetron deposition of a thin film from a multicomponent target consisting of vanadium, platinum, and nickel onto silicon and the subsequent stage thermal treatment. Using the developed technique, we fabricated device structures with the 0.69–0.71-V-high Schottky barriers. It is established that the barrier layer comprises the Ni1 − xPtxSi silicide phase and about 2 at % of platinum in the contact region. We show that the amount of platinum at the interface with silicon determines the barrier’s height. The highest platinum content at the interface is ensured at the two-stage thermal treatment at a first stage temperature of 240–300°C. The use of the two-stage thermal treatment in the silicide formation in the system’s silicon-composite Ni-Pt-V alloy allows obtaining a silicide layer with higher structural quality and a better silicon/silicide interface than the one-stage treatment can yield.