Properties of metal-semiconductor and metal-insulator-semiconductor junctions on CdTe single crystals

Metal-semiconductor and metal-insulator-semiconductor junctions, involving the thermal oxide cadmium tellurite (CdTeO3), have been fabricated on both p- and n-type cadmium telluride (CdTe) single crystals. The oxide is effective in increasing the photovoltaic performance of these junctions only in the case of n-type material. For n-type CdTe, the oxide increases the open- circuit voltage over that of the Schottky barrier, whereas for p-type CdTe the oxide decreases the open-circuit voltage. These and several other junction properties may be understood in terms of proposed energy-band diagrams for Cr/CdTeO3/p-CdTe and Au/CdTeO3/n-CdTe structures