The study of loss kinetics of current carriers in copper-indium-gallium selenide by microwave photoconductivity method

Abstract

This study investigated how stoichiometry affects processes associated with current carriers by undertaking a kinetics investigation of electron loss processes in the copper-indium-gallium selenide (CIGS) samples prepared by PVD and sol-gel methods. Owing to these processes, the current carriers generated by light can be trapped or recombined after a thermalization process and fail to reach electrodes during their lifetime and adversely impact the photovoltaic performance of solar elements. The microwave photoconductivity method provides an effective means of obtaining data on the lifetime and energy distribution of traps for current carriers. Experimental results indicate that the free electron lifetimes in the best samples prepared in both methods are approximately the same, yet decrease with a decline in stoichiometry.