H-ATOM REACTIONS WITH GAAS (001)

A GaAs 〈001〉 crystal at room temperature has been exposed to a flux of hydrogen atoms with and without simultaneous 2-keV argon ion bombardment. A modulated molecular beam mass spectrometric detection system is used to monitor the volatile products evolved from the surface, and in situ Auger electron spectroscopy is used to monitor the surface conditions. With the H atom flux alone no volatile products were observed but an arsenic deficiency was seen with Auger electron spectroscopy. With simultaneous H atom exposure and Ar+ bombardment, arsenic hydrides were observed with the mass spectrometer and a larger arsenic deficiency was observed on the processed surface. No gallium hydrides were observed at any time.