A method of manufacturing copper-indium-gallium-diselenide (CuIn.sub.x Ga.sub.1-x Se.sub.2 or just CIGS) photovoltaic devices using elemental selenium and without requiring complex codeposition or requiring the use of toxic H.sub.2 Se gas. A precursor taking one of several forms is deposited onto a substrate having a back contact. A first precursor includes copper, gallium, and indium, the latter of which is deposited in the presence of a selenium flux, all deposited in that order. The second precursor includes indium deposited in the presence of a selenium flux, copper, and gallium, deposited in that order. Next, the precursor is selenized using one of two techniques: an indium-gallium removal technique and a copper-top technique. In both techniques, the precursor is heated to and held at a first selenization temperature, most preferably 450.degree. C., and then heated to and held at a second selenization temperature, most preferably 550.degree. C. In the indium-gallium removal technique, the heating stages and the first hold are done in a selenium flux that is relatively constant and the selenium flux is decreased to zero during the second hold stage. In the copper-top technique, additional copper is added during the first or second hold stages; both heating stages and both hold stages are done in a selenium flux that is relatively constant and the selenium flux is decreased to zero afterwards during a cooling stage.
Morel, Don Louis and Zafar, Syed Arif, "Method of manufacturing CIGS photovoltaic devices" (2001). USF Patents. 801.
University of South Florida