Reactive magnetron sputtering of transparent and conductive zinc oxide films deposited at high rates onto CIS/CIGS photovoltaic devices

Reactively sputtered ZnO from metal targets enjoys dual advantages of higher deposition rates and lower target costs than RF sputtering from ceramic targets. High deposition rate and conductive, aluminum-doped zinc oxide (ZnO:Al) thin-film materials have been fabricated by DC-powered reactive sputtering from a zinc-aluminum metal alloy target. Reliable process control of material properties is exercised by cathode voltage control. Data is presented on the process control and materials properties of the ZnO:Al thin films produced by DC reactive sputtering from metal targets. These materials were incorporated in copper indium diselenide (CIS) photovoltaic devices, and have resulted in AM1.5 efficiencies over 10%.