Ar ion induced copper germanide phase formation at room temperature

Abstract

The copper germanide phase Cu3Ge which is emerging as an alternative material for making contacts and interconnects for semiconductor industry has been producect across the interface ofCu/Ge hilayers by ion beam mixing at room temperature using 1 MeV Ar ions. The dose dependence of the thickness of the mixed region shows a diffusion controlled mixing process. The experimental mixing rate and efficiency for this phase are 5'35 nm ~ and 10-85nm~/keV respectively. At doses above 8 x l0 ts Ar/cm 2 the formation and growth of another copper rich phase CusGe has been observed. The present theoretical models are inadequate to explain the observed experimental mixing rate.