Influence of bandgap grading of intrinsic layer and annealing post on the optical and electrical performance of amorphous silicon germanium thin film solar cells

摘要

Hydrogenated amorphous silicon germanium (a-SiGe:H) single junction pin sequence solar cells with different bandgap structure of intrinsic layer were prepared by radio frequency plasma enhanced chemical vapor deposition (RF-PECVD). Three kinds type of intrinsic layer using in this study were non-grading structure, Ⅴ type grading and reverse V type grading. The effects of different intrinsic layer structure on solar cell performance were systematically studied. The results showed that the optimized structure of intrinsic layer was the reverse Ⅴ type grading structure. And the performance of a-SiGe:H solar cell with reverse Ⅴ type grading after annealing also were studied. The results revealed that the performance was improved after first annealing, but was deteriorate for further annealing. And, we have studied the dark Ⅰ-Ⅴ curves in order to contribute to a better understanding of the basis of solar cells.