Synchrotron Radiation Photoelectron Spectroscopy Study of Thermally Grown Oxides on 4H-SiC(0001) Si-Face and (000-1) C-Face Substrates

Abstract

The fundamental aspects of thermal oxidation and oxide interface grown on 4H-SiC(0001) Si-face and (000-1) C-face substrates were investigated by means of high-resolution x-ray photoelectron spectroscopy (XPS) using synchrotron radiation together with electrical measurements of SiC-MOS capacitors. We found that, for both cases, there existed no distinct C-rich transition layer despite the literature. In contrast, atomic scale roughness causing degradation of SiC-MOS devices, such as negative fixed charge and electrical defects just at the oxide interface, was found to be introduced as thermal oxidation progressed, especially for the (000-1) C-face substrate.