Formation of fine-textured surface on as-cut crystalline silicon wafers by microparticle-assisted texturing (MPAT) process

摘要

Recently heterojunction back-contact (HBC) crystalline silicon (c-Si) solar cells with efficiency >26% have been developed . Reducing the thickness of c-Si to <100 μm is one of the keys to low-cost solar cells. Usually, the surface of the c-Si is textured for good light confinement and improvement of the cell efficiency. On such thin c-Si wafers, reducing the size of textures is necessary to minimize c-Si losses by texturing process and to keep robust property during cell fabrication. To obtain the textures with a size <2 μm using alkaline anisotropic etching, we have already established “microparticle-assisted texturing” (MPAT) process. However, up to now, the MPAT process has been being applied to only mirror-polished c-Si wafers . Usually in solar cell manufactures, as-cut wafers are directly dipped into texturing solutions for reducing the cost. Therefore, in this work, we aimed to investigate the feasibility of the MPAT process on the as-cut c-Si wafers. Fundamentals and advantages of the MPAT process will be revealed.