Fabrication of 40 µm thin silicon solar cells with different crystal orientation by SLiM-cut process

Thin silicon foils with two different crystal orientation were fabricated by SLiM-cut method. The thickness of the <;100> and <;111> foils are 45 μm and 33 μm, respectively. The surface quality was compared in this study. The <;111> foil have smoother surface than the <;100> foil. 4cm2 thin silicon solar cells with heterojunction structure were fabricated. The efficiency was found to be 10.74% and 12.81% for the <;100> and <;111> solar cell, respectively. The surface quality of the silicon foils was found to affect the solar cell character. However, the Voc of <;100> solar cell is higher than <;111> solar cell. It was believed that the local epitaxial occur when the amorphous silicon was deposited on the <;111> surface. The increasing of dangling bonds will become the recombination center and reduced the Voc of solar cell.