BROMINE-METHANOL AS AN ETCHANT FOR SEMICONDUCTORS - A FUNDAMENTAL-STUDY ON GAP .2. INTERACTION BETWEEN CHEMICAL AND ANODIC ETCHING OF P-TYPE GAP

Rotating disk and rotating ring-disk electrode experiments were performed to investigate the anodic behavior of dark p-type GaP electrodes in bromine-methanol solutions. A strong interaction occurred between chemical etching of the semiconductor by bromine and anodic decomposition. A mechanism for the anodic dissolution reaction is proposed in which electrochemical as well as chemical reaction steps participate. Marked differences between the polar (111) and (111BAR) faces are observed and discussed.