Direct texturization of as sawed mono-crystalline silicon solar wafers: Solar cell efficiency as a function of total silicon removal

Sawed p-type Czochralski wafers with a bulk resistivity of 1-5ωcm were subjected to single step texturization process by using a non-alcoholic chemical etching formulation. The minimum amount of silicon removal required for achieving optimum solar cell efficiencies was estimated by measuring cell efficiency as a function of silicon loss. The surface damage layer of as cut wafers was found to be approximately 6μm deep as indicated by the minority carrier lifetime measurements. However for attaining minimum surface reflectivity it was required to remove at least 20μm of silicon from the initial wafer. Further removal of silicon offered no additional improvements in surface reflectivity or the solar cell efficiency.