Experimental study on the effect of different etching methods for texturization of mono-cSI wafers required for the fabrication of solar cells

Abstract

Etching methods were developed for texturization study on mono-cSi wafer required to have a fabrication processing of solar cells. The etching effects on quantum efficiency of solar cells. We compare three different etching methods (Recipe 1: CH 4 O/ C 3 H 6 O, recipe 2: NaOH/HF, Recipe 3: HNO /HF ) on surface texturization of mono-crystalline Si wafers in an KOH/IPA solution. With a better saw damage removal method bigger pyramids can be seen than those at the more contaminated zones, causing homogenous textured figure and reflectance uniformity on wafer surfaces. Spectral response measurement system (200mv/ 400nm-1200nm) and Scanning electron microscope (operated at 20 KV, magnification: ×5000- ×50000) were used to differentiate the etching quality of several recipes by analyzing change of reflectance and surface morphology respectively. Bigger pyramids found on mono-cSI wafer etching by method 1, which reflects the quality of reflectance of wafer. Spectral response of this wafer was also studied. Percentage Reflectance with respect to mirror image was measured from graphical analysis. Saw damage removal process may require to be customized to attain consistent and desired texturization outputs.