An alternative model for V, G and T dependence of CdTe solar cells IV characteristics

It is generally assumed that the main features of CdTe IV curves (rollover, crossover) depend on a reverse diode located at the back contact. The front region of CdTe solar cells can play an equally important role in determining voltage, irradiance and temperature dependence of the IV characteristics. We propose a model of current transport that relies on the presence of a light and temperature dependent majority carrier barrier in the band diagram. We infer that this barrier forms as a consequence of intermixing at the TCO/CdS and CdS/CdTe interfaces and compensation of donors in CdS. Numerical simulation gives consistent results with the observed measurement characteristics.