Maskless Dry Etching of Gallium Arsenide with a Submicron Line-Width by Laser Pyrolysis in CCl4 Gas Atmosphere

Localized etching of GaAs using Ar ion laser beams focused down to 1.2 µm has been performed in a CCl4 atmosphere to realize a maskless dry etching process with a submicron line-width. It was found that etched line patterns with a line-width down to 0.6 µm could be obtained by laser irradiation with a power of 80 mW in a CCl4 atmosphere at a pressure or 30 Torr. Etching rates ranged from 2.2 to 6.3 µm/s, which were greater by up to 4 orders of magnitude than those of ultraviolet laser photolysis.