With the aid of deep-level transient spectroscopy, a study was made of the deep levels in CdS/CdTe thin-film solar cells with a Te:Cu back-contact. One hole trap and one electron trap were observed. The hole trap, localized at Ev+0.128eV, originated from the Cd vacancy (VCd). The electron trap, found at Ec−0.178eV, was considered to be correlated with interstitial Cuj+ in CdTe.

Deep Level Transient Spectroscopy Investigation of Deep Levels in CdS/CdTe Thin Film Solar Cells with Te:Cu Back Contact. Z.Wang, B.Li, X.Zheng, J.Xie, Z.Huang, C.Liu, L.H.Feng, J.G.Zheng: Chinese Physics B, 2010, 19[2], 027303