Study on a novel fixed and free abrasive combined wire sawing multi-crystalline silicon wafers for wet acid texturization

In preparation of solar cells, the multi-crystalline silicon (mc-Si) wafers cut by diamond wire sawing can't obtain the ideal texturization effect when using the wet acid etching process. In this paper, a novel fixed and free abrasive combined wire saw technology for slicing mc-Si wafers is proposed. Diamond saw wire is used as the main processing tool, and free SiC abrasive particles are added into the lubricating coolant to lap the surface of mc-Si wafers. The results show that there are no significant saw marks and ductile smooth area on the surface of mc-Si wafer processed by the combined wire sawing when the SiC abrasive mass fraction is appropriate. The surface roughness and fracture strength of mc-Si wafers in parallel and perpendicular the saw wire motion directions tend to be the same. And the anisotropy of mechanical properties of mc-Si wafers in different directions is significantly reduced, which is conducive to reducing the wafers breakage. Compared with the diamond wire sawn wafer, the reflectivity of the mc-Si wafer cut by the combined wire sawing is greatly reduced after wet acid etching, which can meet the needs of solar cell preparation. The research results provide references for the development of PV mc-Si slicing technology.