Published online by Cambridge University Press: 16 February 2011
We have studied the saturation behavior and thermal annealing recovery of light-induced degradation in amorphous silicon-germanium (a-SiGe:H) alloy solar cells with various Ge contents. In contrast to amorphous silicon (a-Si:H) alloy cells, a-SiGe:H alloy cells with high microvoid density show similar thermal annealing behavior to those with lower microvoid density. Infrared studies show that unlike a-Si:H alloys, a-SiGe:H alloys with higher microvoid density do not show higher hydrogen or dihydride content. Moreover, even with a Ge-content of 41 %, there is saturation in degradation after light soaking for 1000 hours.