Silicide Formation and Thermal Stability of Ni/Si/GaAs Interface

Abstract

The suicide formation and thermal stability of the Ni/Si/GaAs structures have been investigated. Vacuum deposited Ni and Si onto a (100) GaAs were annealed at temperatures between 500 °C and 650 °C. In the case that the relative amount of Ni and Si was unity, a stoichiometric NiSi was formed and silicide/GaAs interface was quite stable. The Stoichiometric NiSi did not decompose into NiSi2 and Ni at a temperature of 650 °C. When Ni was in excess in amount for the formation of stoichiometric nickel suicides, free Ni atoms were generated, resulting in unstable interfaces.