BCL3 N-2 DRY-ETCHING OF INP, INALP, AND INGAP

Etch rates for InP, InAlP, and InGaP can be controlled between similar to 1500 Angstrom/min and >1 mu m/min by varying the microwave power, rf power, or N-2 composition in BCl3N2 discharges under electron cyclo tron resonance conditions. The surface morphology of InGaP is poor at low microwave power (250 W), but becomes very smooth at high powers (1 000 W). InP has exactly the opposite dependence on microwave power, wh ile InAlP shows little change in morphology over a wide range of power s. The high ion current under electron cyclotron resonance conditions enables etching of In-based semiconductors without the need for high s ample temperatures to enhance desorption of InClX species. (C) 1996 Am erican Vacuum Society.