ArF-Excimer-Laser-Assisted Highly Selective Etching of InGaAs/InAlAs Using HBr and F 2 Gas Mixture

Highly selective etching of InGaAs/InAlAs was achieved by irradiation with a 193-nm ArF excimer laser in a HBr and F 2 atmosphere. Adding F 2 gas to the HBr gas enhanced the InGaAs etching rate while reducing the InAlAs etching rate, resulting in an etching rate ratio of over 450. The etching mechanism is discussed in terms of pressure dependence and laser fluence dependence data. Our findings suggest that ArF-excimer-laser-assisted etching is feasible for gate-recess etching of InGaAs/InAlAs field effect transistors.