Laser Induced Local Etching of Gallium Arsenide in Gas Atmosphere

Pyrolytic local etching of GaAs using focussed Ar laser beams in CCl4 gas atmosphere was performed to investigate the possibility of maskless etching processes by laser beams. Etching was found to take place only for the laser-irradiated area and etching rates from 0.3 to 40 µm/scan with an etched linewidth from 7 to 70 µm were obtained at CCl4 pressure of 80 Torr. A carbon line buried in GaAs was, for the first time, obtained for a single scan of a laser beam with low scanning speeds.