Control of CuInSe2 film quality by substrate surface modifications in a two-stage process

An approach has been developed for the preparation of Cu-In precursor layers to be used in the selenization technique. In this approach, the surface of the Mo-coated substrate was chemically modified to improve the growth characteristics of the precursors. Selenization of improved precursors yielded stoichiometrically, morphologically, and mechanically superior CuInSe₂ films which were used to fabricate over 12 % efficient solar cells. It should be noted that although the specific example presented involves Te interfacial layers and precursors obtained by depositing the In layer first, the technique should be applicable to the more commonly used Mo/Cu/In structures and interfacial layers of other materials