The Preparation of High Quality CIS Films by Spraying Citrate-Capped Cu11In9 Alloy Nanoparticles Ink and RTP Process

A facile low-cost non-vacuum process for fabrication of high quality CuInSe2(CIS) films is described, which indicates a promising way for the application in thin film solar cells. First, citrate-capped Cu11In9alloy nanoparticles are synthesized by hot-injection method after a system research on the different reaction time and Cu-In ratio of the raw materials. From the TEM and XRD results, we can see that uniform spherical nanoparticles with dominant Cu11In9phase and less particle-to-particle agglomeration are successfully achieved in this study. Then, employing spray and RTP selenization process, high quality CIS films with dense and big grains are obtained, which show the single chalcopyrite structure and the preferred (112) orientation. An energy band gap about 1.01 eV is measured through the absorption spectroscopy measurement in our work.