A study on the surface characteristics of diamond wire-sawn silicon wafer for photovoltaic application

(Received September 30, 2011)(Revised October 21, 2011)(Accepted November 4, 2011)Abstract Most of the silicon cutting methods using the multi-wire with the slurry injection have been used for wafers ofthe crystalline solar cell. But the productivity of slurry injection cutting type falls due to low cutting speeds. Also, thedirect contact with the metal wire and silicon block increases the concentration of metallic impurities in the wafer’ssurface. In addition, the abrasive silicon carbide (SiC) generates pollutants. And production costs are rising because it doesnot re-use the worn wire. On the other hand, the productivity of the cutting method using the diamond coated wire isabout 2 times faster than the slurry injection cutting type. Also, the continuous cutting using the used wire of low wear ispossible. And this is a big advantage for reduced production costs. Therefore, the cutting method of the diamond coatedwire is more efficient than the slurry injection cutting technique. In this study, each cutting type is analyzed using thesurface characteristics of the solar wafer and will describe the effects of the manufacturing process of the solar cell.Finally, we will suggest improvement methods of the solar cell process for using the diamond cutting type wafer.Key wordsSilicon, Silicon wafer, Diamond coated wire, Diamond wire saw, Surface roughness, Metal impurity, Damagedepth, Texturing