Electrical and Microstructural Properties of Pt-Germanides Formed on p-Type Ge Substrate

Abstract

We have investigated electrical and microstructural properties of Pt-germanides as a function of rapid thermal annealing (RTA) temperature. As increasing RTA temperatures, Pt films reacted with Ge and produced Pt-germanides. The Pt2Ge3 phase was completely transformed into PtGe2 at the RTA temperatures in the excess of 500°C. The specific contact resistivity (c) and sheet resistance (Rs) were investigated as a function of germanidation temperatures. Both c and Rs increased after the RTA process of 400°C, and then decreased with increasing annealing temperature. The increase in R s and c at 400°C could be associated with the presence of a highly resistive Pt2Ge3 phase. RTA process at 700°C led to the severe degradation of surface and interface morphologies of a PtGe2 film caused by the agglomeration. This could be responsible for the main contribution to the increase in Rs and c. © 2011 The Electrochemical Society.