Silicon solar cells and material near the transition from microcrystalline to amorphous growth

This work describes properties of films and solar cells prepared under deposition conditions close to the transition from amorphous silicon (a-Si:H) to microcrystalline silicon (/spl mu/c-Si:H) growth and vice versa. The transition from a-Si:H to /spl mu/c-Si:H shifts to a lower silane concentration when using a-SiC:H p-layers compared to films deposited directly on the glass or on /spl mu/c-Si:H p-layers. Solar cells deposited under identical deposition conditions using a-SiC:H p-layers or /spl mu/c-Si:H p-layers can result in high band gap a-Si:H solar cells or typical /spl mu/c-Si:H solar cells, respectively. When increasing the i-layer thickness of solar cells prepared close to the transition from a-Si:H to /spl mu/c-Si:H using a-SiC:H p-layers the crystalline volume fraction increases. As soon as the crystalline volume fraction of the i-layer increases the fill factor and open circuit voltage decreases. We could achieve a maximum open circuit voltage of 988 mV for our solar cells.