Influence of CdS/CdTe Interface Properties on the Device Properties
نویسندگان
چکیده
In this paper, we have focused on the formation and the role of CdS/CdTe interface on CdTe solar cells. The devices were made using chemical bath deposited (CBD) CdS on SnO2/glass substrates and the CdTe was deposited by close spaced sublimation (CSS). CdTe was treated with CdCl2 : known to be a key processing parameter. Compositional analysis showed considerable interdiffusion of Te and S as well as Cl accumulation at the interface. Microphotoluminescence (PL) analysis reveals sulfur accumulation at the grain boundaries and a graded CdSxTe1-x alloy at the interface. Our analysis leads us to conclude that Cl accumulation and anion vacancies result in a one sided n-p junction. This model could explain the collection loss in the CdS layer, seen in the spectral response of CdS/CdTe devices.
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