Condensed chlorine etching of GaAs induced by excimer laser radiation

Abstract

We report excimer-laser-induced etching of GaAs surfaces covered with a layer of condensed Cl2. The experiments were performed at low temperatures (120–150 K) and in a chlorine ambient (P=1–40 mTorr). Spatially well-resolved, anisotropic etching has been demonstrated with an observed etch rate of 0.25 Å/pulse (0.1 μm/min for typical parameters). The etch rate is characterized as a function of the various system parameters (pressure, temperature, laser repetition rate, and fluence, etc.), and a model is proposed to describe the etching mechanism.