Current transport in boeing (Cd, Zn)/CuInSe2solar cells

The current versus voltage (I-V) and capacitance characteristics of Boeing (Cd, Zn)S/CuInSe2solar cells are investigated and a model for the current transport is proposed. The current transport appears to involve tunneling and interface recombination in series. A mathematical model for current transport is formulated as a linear transition between the well known tunneling and interface recombination transport equations. This model is found to explain observed I-V characteristics under various temperature and illumination conditions. In particular, the nontranslation of the I-V characteristics from dark to illuminated conditions and the temperature dependences of the diode factor and the reverse saturation current can be explained. In addition, capacitance analyses have corroborated assumptions concerning the band structure and have provided independent demonstration of tunneling transport.