Nonuniformity Characterization of CdTe Solar Cells Using LBIC

Light-beam-induced current measurements have been used for characterization of nonuniformities in cadmium telluride (CdTe) solar cells. Spectral dependence, voltage-bias dependence, and resolution dependence are used for detailed characterization of nonuniformities in junction quality, window thickness, and absorber band gap. These tools were applied to CdTe cells and used to identify thin regions in the CdS layer, regions of modified band gap, and weak diode regions. In addition, an improved procedure has allowed for shorter measurement times without discernable loss of accuracy.