Doping Control of MgxZn1-xO Emitter through Fluorine Incorporation

Abstract

Doping control of the emitter is critically important to high performance thin film photovoltaic devices. Here, we deposit magnesium zinc oxide (MZO) thin films for use as the emitter of CdTe-based devices through cosputtering of ZnO and MgO or MgF. The bandgap and sheet resistance of the MZO films are measured before and after the films are thermally processed under vacuum or in He environments. Through annealing of the films, they become conductive, but little bandgap or sheet resistance differences can be determined between the films deposited using the MgO target or the MgF target. Devices will be completed to determine if the addition of fluorine to the MZO film affects the emitter doping during device processing.