Texturing techniques and resulting solar cell parameters on tri-silicon material

Tri-crystalline silicon material (Tri-Si) is a promising alternative to mono-crystalline CZ silicon because of a faster crystallization process and higher wafer stability. The orientation of the three crystals [110] is different to the [100] orientation in CZ material typically used in the photovoltaic industry. As a consequence the common alkaline texture technique using KOH or NaOH cannot be applied. For this reason we compared several alternative texturing methods like mechanical grooving and acidic texture etching, which work independently of crystal orientations. Solar cells were processed from these wafers, and an overview of their surface morphology as well as the resulting cell parameters is given. By applying an antireflection coating we reached the highest efficiencies reported on Tri-Si material.