A new technique for fabricating thin films ofCuInSe2and its alloys for low-cost photovoltaics has been developed. The technique uses simple, self-limiting, non-vacuum processes to prepare particulate precursor materials, to deposit layers of these precursor materials, and to convert the precursor layers intoCuInSe2films. An NREL confirmed 8.5&percent; efficient solar cell has been achieved withCuIn1−xGaxSe2in early research. The simplicity and low cost of the technique are well suited to manufacturing in a wide variety of settings, including in developing countries where industrial infrastructure is currently limited. ©1999 American Institute of Physics.