The effect of doping with copper and chlorine on various properties of vacuum-evaporated CdS and CdSe doube layers has been studied. The properties specifically studied including: (1) the dark conductivity and photo-conductivity as functions of the doping concentration and the radio of copper to chlorine, (2) the response time of various photo-conductive films and (3) the spectral response. It was found that the dark conductivity decreases and the photo-conductivity increases significantly if the ratio of Cu to Cl is suitable. The response time was about 5～10 ms for doping films and more than 100 ms for undoping ones. The optical absorption increases and the spectral response moves to a longer wavelength as the concentration of CdSe increases. The response wavelength can be changed by adjusting the thickness ratio of CdS to CdSe.