ABSTRACTIn previous work [1,2], we modeled the cross-over of the I-V curves of thin film CdS/CdTe solar cells in terms of an electron (minority carrier) current in the vicinity of the back contact. In this work, we focus on the necessary extension of this analytical model based on a series of measurement results. Especially the wavelength and voltage dependence of the current at forward bias is illustrated in these measurements. The various possible causes for this kind of behavior are discussed and modeled. The extensions to the previous model, needed to describe the voltage and wavelength dependent behavior of I-V curves of real CdTe/CdS solar cells, are proposed.
Excess dark currents and transients in thin-film CdTe solar cells: implications for cell stability and encapsulation of scribe lines and cell ends in modules