(PHOTO)ELECTROCHEMISTRY - A SUITABLE TOOL FOR INVESTIGATING WET ETCHING PROCESSES ON III-V SEMICONDUCTORS

Wet etching processes at III-V semiconductors are studied both from the viewpoint of the reaction mechanisms and from that of the morphology of the etched surfaces. Emphasis is put on GaP single crystals, for which four different types of etching are considered, ie (photo)anodic, electroless, chemical and photoetching. Relations between etching kinetics, crystallographic orientation and etching morphology are discussed. These relations, as well as observed differences in etch morphology between n- and p-type crystals, are shown to be very often interpretable on the basis of electrochemical concepts as established by (photo)anodic studies.