Study of Ge out-diffusion during nickel (Platinum - 0, 5, 10 at.%) germanosilicide formation

Abstract

The interfacial reaction between 10 nm Ni(Pt ∼0, 5, 10 at.%) and (100) Si 0.75Ge 0.25 substrate after rapid thermal annealing between 400 and 800°C has been studied in detail using Micro-Raman spectroscopy. Only monogermanosilicide phase was detected in the temperature range investigated. The evolution of a broad Ni(Pt)SiGe Raman peak into two distinct peaks with increasing annealing temperature is attributed to a Ge out-diffusion from the germanosilicide grains. In addition, Raman spectroscopy further proves that depletion of Ge concentration in the Ni(Pt)SiGe grains reduces at higher temperature by the addition of Pt. The above phenomena were further supported by X-ray diffraction method.