Temperature Coefficient Characterization Of Cigsse Solar Cells With Layer Modifications

One of the advantages of Cu(In,Ga)(S,Se)2 (CIGSSe) thin film solar cells is the lower temperature sensitivity of the solar cell parameters as compared to conventional silicon-based technologies. To further improve and to tailor CIGSSe temperature behavior for different environments, it is important to gain a detailed understanding of the microscopic mechanisms involved. The goal of the current study is to elucidate the impact of the individual functional layers within the CIGSSe solar cell stack on the temperature dependence of the overall cell performance. For this purpose, temperaturedependent current-voltage measurements were performed on a selected set of CIGSSe cells, containing a systematic variation of functional layers. The experimental results demonstrate that the absorber layer exhibits the largest influence on the temperature dependence of the power efficiency. An analysis of the contributing parameters revealed that the temperaturedependence of the power efficiency is mainly governed by a change in the open-circuit voltage. The temperature coefficient of the open-circuit voltage is analyzed in terms of the cell?s physical parameters, including their minimum band gap and the temperature-dependence of the dark saturation current.