Investigation of HF/H2O2 Concentration Effect on Structural and Antireflection Properties of Porous Silicon Prepared by Metal-Assisted Chemical Etching Process for Photovoltaic Applications

Porous silicon was successfully prepared using metal-assisted chemical etching method. The Effect of HF/H2O2 concentration in etching solution as an affecting parameter on the prepared porosity type and size was investigated. Field emission electron microscopy (FE-SEM) confirmed that all etched samples had porous structure and the sample which was immersed into HF/H2O2 withmolar ratio of 7/3.53 had the smallest porosities. The average roughness of 288 nm and reflectivity as low as 7% could be achieved using this molar ratio. The Raman peak appeared at 520.09 cm-1 confirmed that there weren’t any defect and stress in the porous structure. The prepared porous silicon had potential candidate for replacement with antireflective layer in photovoltaic devices because of their low production cost, high antireflective property, and possibility of integration process relative to other antireflection layers.