The influence of air heat treatments on Cu/sub x/S sheet resistance and CdS--Cu/sub x/S solar cell performance. Technical report

Changes in the electrical sheet resistance of Cu(/sub x/)S and in the photovoltaic response of CdS--Cu(/sub x/)S cells have been measured as functions of thermal aging in air at 250C. It was found that sheet resistance (or bulk resistivity) initially increases and then decreases with aging. Maximum Cu/sub x/S bulk resistivity values were found to be about 0.1 ohm-cm. Cell electrical parameters were monitored with air heat treatments, degradation being accompanied by a decrease in Cu/sub x/S sheet resistance. The rates of change of Cu/sub x/S sheet resistance and cell light response with time in air at 250C are apparently enhanced by cell surface roughness. Some possible mechanisms are presented to account for observed behavior.