Collection length and optical path improvement in a-Si:H solar cells

Amorphous silicon thin film solar cells exhibit a degrading effect during the first hours of illumination. This phenomenon is worsen by thick intrinsic layers, thus light trapping strategies are employed to increase optical absorption. We use a method developed to measure the performance of these techniques. The procedure allows us to approximate both, the effective path of light inside the cell and the collection length of carriers, out of the internal quantum efficiency. Simulated and experimental data were compared finding good agreement.

keywords: a-Si:H thin film solar cell, Internal quantum efficiency, Collection length, Optical path enhancement, Light trapping