Photoelectron spectroscopic studies on interfacial reactions in Zr/2×1(100)Si and Zr/SiO2/(100)Si systems

Abstract

Interfacial reactions in Zr/clean-2×1(100)Si and Zr/SiO2/(100)Si systems have been studied by x-ray and ultraviolet photoelectron spectroscopy. It has been found that no silicidation reaction occurs at the Zr/2×1(100)Si interface at temperatures below 400 °C and, however, the existence of a thin SiO2 layer at the interface causes interfacial reactions even at as low as 80 °C. The silicidation in the latter system is thought to be initiated by Si atoms produced by the reduction of SiO2 due to chemically active Zr. Chemical shifts of core levels of Zr 3d5/2 and Si 2p electrons due to the silicidation are found to be +0.3 and −0.6 eV, respectively