Photochemical Etching of GaAs using Synchrotron Radiation

Abstract

The photochemical etching of gallium arsenide by chlorine was investigated using synchrotron radiation. At the substrate temperatures above 25°C, both the irradiated and nonirradiated regions were uniformly etched. In case of substrate temperatures below -25°C, highly selective etching was observed in the irradiated region. We considered that at low temperatures, etching reaction caused by gas-phase excitation is suppressed and photochemical surface reaction becomes dominant.