Reactive Ion-Beam Etching of InP with Cl2

Abstract
Reactive ion-beam etching (RIBE) of InP with Cl2 at room temperature has been studied by varying the ion extraction voltage and the gas pressure. The sputtering yield is found to increase linearly with the ion extraction voltage above a threshold voltage. RIBE with a higher Cl2 gas pressure is dominated by the chemically reactive etching, and offers a higher etch rate and a smoother surface. Smooth surfaces with low concentrations of residual Cl atoms are obtained under the ion extraction voltage of 400 V and Cl2 gas pressure of 2.5×10-3 Torr.