Recombination-induced voltage-dependent photocurrent collection loss in CdTe thin film solar cell  

作　　者：Ling-Ling Wu Guang-Wei Wang Juan Tian Dong-Ming Wang De-Liang Wang 吴玲玲;王光伟;田涓;王东明;王德亮(Hefei National Laboratory for Physical Sciences at Microscale,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]Hefei National Laboratory for Physical Sciences at Microscale,University of Science and Technology of China,Hefei 230026,China

出　　处：《Chinese Physics B》2022年第10期607-616,共10页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 61774140 and 61474103)。

摘　　要：Recently, the efficiency of CdTe thin film solar cell has been improved by using new type of window layer Mg_(x)Zn_(1-x)O(MZO). However, it is hard to achieve such a high efficiency as expected. In this report a comparative study is carried out between the MZO/CdTe and CdS/CdTe solar cells to investigate the factors affecting the device performance of MZO/CdTe solar cells. The efficiency loss quantified by voltage-dependent photocurrent collection efficiency(ηC(V′)) is 3.89% for MZO/CdTe and 1.53% for CdS/CdTe solar cells. The higher efficiency loss for the MZO/CdTe solar cell is induced by more severe carrier recombination at the MZO/CdTe p-n junction interface and in CdTe bulk region than that for the CdS/CdTe solar cell. Activation energy(Ea) of the reverse saturation current of the MZO/CdTe and CdS/CdTe solar cells are found to be 1.08 e V and 1.36 e V, respectively. These values indicate that for the CdS/CdTe solar cell the carrier recombination is dominated by bulk Shockley-Read-Hall(SRH) recombination and for the MZO/CdTe solar cell the carrier recombination is dominated by the p-n junction interface recombination. It is found that the tunneling-enhanced interface recombination is also involved in carrier recombination in the MZO/CdTe solar cell. This work demonstrates the poor device performance of the MZO/CdTe solar cell is induced by more severe interface and bulk recombination than that of the CdS/CdTe solar cell.

关 键 词：CdTe solar cell voltage-dependent photocurrent collection efficiency interface recombination bulk recombination 

分 类 号：O646[理学—物理化学] TM914.42[理学—化学]