Abstract
CuInS2 (CIS) films for solar energy applications are typically made by rapid thermal sintering of the elements on a molybdenum‐coated glass substrate. The photovoltaic cell is then completed by adding a CdS buffer layer and an Al/ZnO transparent electrode, all in all an expensive process. A low‐cost colloidal route to nanocrystalline ZnO/CIS bilayers on indium tin oxide (ITO) glass is presented here, together with the optical and electrical characterization of the films. The concentrated coating colloids with size‐quantized CIS particles that were developed for the film deposition are described.