A PROCESS FOR LARGE-SCALE PRODUCTION OF CdTe/CdS THIN FILM SOLAR CELLS, WITHOUT THE USE OF CdCl2

A process for the large-scale production of CdTe/CdS thin film solar cells, said films being deposited as a sequence on a transparent substrate, comprising the steps of: depositing a film of a transparent conductive oxide (TCO) on said substrate; depositing a film of CdS on said TCO film; depositing a film of CdTe on said CdS film; treating said CdTe film with a Chlorine-containing inert gas; depositing a back-contact film on said treated CdTe film. The Chlorine-containing inert gas is a Chlorofluorocarbon or a Hydrochlorofluorocarbon product and the treatment is carried out in a vacuum chamber at an operating temperature of 380-420C. The Chlorine released as a result of the thermal dissociation of the product reacts with solid CdTe present on the cell surface to produce TeCl2 and CdCl2 vapors. Any residual CdCl2 is removed from the cell surface by applying vacuum to the vacuum chamber while keeping the temperature at the operating value.