Sputtered Cadmium Oxide and Indium Oxide/Tin Oxide Films as Transparent Electrodes to Cadmium Sulfide

Abstract

Thin films of cadmium oxide and indium oxide/tin oxide were reactively sputtered from their respective metal or alloy targets. films combine sheet resistances of less than 100 ohms/square with optical transmission greater than 45% for wavelengths greater than 5000Aå, and make ohmic contacts with high‐resistivity films. Indium oxide/tin oxide films show optical transmission greater than 45% for wavelengths greater than 4000Aå and sheet resistances of 100 to 200 ohms/square. Indium oxide/tin oxide also makes useful contacts to films, but reduces the resistivity of the films. A band diagram is proposed which qualitatively explains the ohmic nature of the contacts between two wide bandgap materials.