Effects of sodium on CuIn3Se5 thin films

CuIn3Se5 films have been deposited with Na2S on Coning 7059 glass substrate s by the two-stage co-evaporation method. Stoichiometric CuIn3Se5 films wit h p-type conduction with the resistivities of 10(6) Ohm . cm range were obt ained by our sodium control technique. Enhanced grain growth and preferred (112) orientation were also clearly observed with sodium incorporation; the same effect that has been reported for chalcopyrite CuInSe2 thin films. Th e effects of sodium in these films have been investigated by comparing the electrical and optical properties of CuIn3Se5 films with and without the Na incorporation. A correlation between the photoluminescence spectra and the resistivity or conduction type of the CuIn3Se5 films was found, suggesting a reduction in compensation due to the suppression of donor-type defects b y the presence of Na.