Temperature dependence of maskless ion beam assisted etching of InP and Si using focused ion beam

Abstract

Temperature dependence of maskless ion beam assisted etching for InP and Si has been investigated. Thirty-five keV Ga+ focused ion beam was irradiated on a sample surface in a chlorine gas atmosphere at various temperatures up to 200 °C. The etched surface of InP was analyzed by Auger electron spectroscopy (AES). It was observed that the etching rate for InP increased with increasing temperature and it was 20–30 times larger than that of the physical sputter etching at a temperature of 140 °C. Chlorine was detected on the InP surface etched at temperatures lower than 100 °C, but no chlorine was detected above 140 °C. For Si, 20 times enhanced etching over physical sputter etching was observed near room temperature, but the etching rate decreased with increasing sample temperature.