Evaluation of New Acid Composition for Low Optical Reflectance Texturization of Multicrystalline Silicon Wafer for Solar Cells

Cost-effective solar cell can be fabricated with the use of multicrystalline silicon (mc-Si) wafer. Accordingly, texturization of an mc-Si surface is an important step for fabrication of an mc-Si solar cell as it reduces reflection of light from the surface of the cell. In this study, wet isotropic etchant composition of HF-HNO
₃
- H
₂
SO
₄
-H
₂
O has been considered to texture the mc-Si wafer as a cost-effective and reliable process at room temperature with a faster convergence rate. Concentration variation of H
₂
SO
₄
in the wet acid etchant on both mc-Si etching thickness and etching rates has been studied. Subsequently, the surface morphology has been investigated with the use of field emission scanning electron microscope (FESEM) photograph, which exhibits the nanoporous structures on the surface of the mc-Si wafer. Further, the reflectance from the etched surface of mc-Si also has been measured for the wavelength ranges from 200 to 1200 nm and has been found to be from 3% to 6% to etch with the said acid composition.