Optical Characteristics of Thin CIGS Cells on TCO Back Contact

Reduction of CIGS layer thickness could translate in significant cost reduction. CIGS was made on transparent conductive oxide (TCO) to allow for optical characterization. This data was compared with external quantum efficiency (EQE) data. The results suggest that changes in surface morphology are an important aspect, which has to be taken into account when interpreting the data for thin CIGS cells in conjunction with the effects of reduced absorption associated with thin CIGS layers. EQE with back side illumination suggests that bulk recombination will lead to less than optimal functionality of light management technology implemented at the back side of the cell.