Method of making a transparent conductive oxide layer and a photovoltaic device

A method, comprising:

• disposing a substantially amorphous cadmium tin oxide layer on a support by reactive sputtering from one or more target in an atmosphere comprising oxygen at a concentration greater than about 60% by volume;
• and
• thermally processing the substantially amorphous cadmium tin oxide layer at a temperature in a range from about 550° C. to about 650° C., in an atmosphere substantially free of cadmium from an external source, and at pressure conditions less than atmospheric pressure, to form a transparent layer,
• wherein the transparent layer comprises cadmium tin oxide having a substantially single-phase spinel crystal structure, and has an electrical resistivity less than about 2×10−4 Ohm-cm wherein an atomic ratio of cadmium to tin in the substantially amorphous cadmium tin oxide layer is less than about 2.5:1.

A method, comprising:

• disposing a substantially amorphous cadmium tin oxide layer in an atmosphere comprising oxygen at a concentration greater than about 60% by volume on a support;
• thermally processing the substantially amorphous cadmium tin oxide layer at a temperature in a range from about 550° C. to about 650° C., in an atmosphere substantially free of cadmium from an external source, and at pressure conditions less than atmospheric pressure, to form a transparent layer, wherein the transparent layer comprises cadmium tin oxide having a substantially single-phase spinel crystal structure, and has an electrical resistivity less than about 2×10−4 Ohm-cm;
• disposing a first semiconductor layer on the transparent layer;
• disposing a second semiconductor layer on the first semiconductor layer;
• and
• disposing a back contact layer on the second semiconductor layer to form a photovoltaic device.