Improvement of Voc using carbon added microcrystalline Si p-layer in microcrystalline Si solar cells

We have developed carbon added p-type microcrystalline silicon for the improvement of the open circuit voltage (Voc) of microcrystalline Si solar cells. Voc and fill factor (FF) shows the presence of optimum amount of carbon, [C]/[Si] of about 3.0%. Excess amount of carbon deteriorates the crystallinity of the p-layer accompanied by a decrease in Voc and FF. ng this carbon added p-layer, we have improved solar cell performance. Voc and FF are increased from 0.527 to 0.548 V and from 0.724 to 0.756 V, respectively, for a thickness of 1.3 μm. For a thickness of 2.5 μm, we obtained solar cell with an efficiency of 8.6%.