The behaviour of co-evaporated CuCl/KCl films, with a varying weight percentage of KCl from 0% - 15%, has been investigated using structural, optical and electrical characterisation techniques. Room temperature X-ray diffraction (XRD) measurements reveal that the deposited films on glass substrates were zincblende in structure and preferentially oriented in the CuCl (111) plane irrespective of the percentage of KCl. Temperature dependent photoluminescence (PL) measurements on all samples exhibit various excitonic luminescence processes. Further to this, the normalized peak intensity (Z3 ~ 384 nm) of the 95% CuCl/5% KCl evaporated film is twice that of undoped film due to possible filling of some of the anion vacancies which may reduce the luminescence intensity of the film. The conductivity of the deposited films was found to increase with increasing KCl content. An interstitial hopping mechanism of K+ in a predominantly CuCl crystal was used to explain the increase in the electrical conductivity of the co-evaporated films. Copyright © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.