Modeling of multilayer amorphous thin film silicon-germanium single and tandem solar cells

A straightforward modeling approach has been developed and used for the study of single- and tandem-pin solar cells made from amorphous silicon and its alloys with carbon and germanium before and after degradation. Experimental results on degradation of pure amorphous silicon cells (with SiC p-layer) can only be reproduced in the model by a rise of the bulk density of defect states in the i-layer. At the p-i and the i-n-interface, the defect density must be assumed to be high already before degradation