Efficiency Enhancement by Optimizing Selenization Time for Co-Sputtered Cu2ZnSn(S,Se)4 Thin Film Solar Cells
To reveal the effects of annealing condition on CZTSSe thin film solar cells, co-sputtering and subsequent selenization were used to prepare CZTSSe thin films. Structural, morphological and optical properties of CZTSSe thin films were investigated. CZTSSe thin films with various Se/(S+Se) ratio ranging from 0.69-0.78 were obtained. Representative peaks corresponding to CZTSSe in XRD and Raman results showed a slight shift to lower diffraction angle and wavenumbers. Selenization time significantly influenced the morphologies of CZTSSe films and the gradual grown up grain size was observed. VOC deficit values down to 839 mV was achieved for the best cell. CZTSSe solar cell with the selenization time of 10 min showed a best conversion efficiency of 5.32%, which presented a 50% enhancement comparing to the solar cells with insufficient and over-selenized absorbers.
Henry Hu and Gu Xu
L. H. Sun et al., "Efficiency Enhancement by Optimizing Selenization Time for Co-Sputtered Cu2ZnSn(S,Se)4 Thin Film Solar Cells", Key Engineering Materials, Vol. 793, pp. 35-39, 2019