Texture Etching of Si with Atomic Hydrogen Generated by Hot Wire Method through SiO₂ Masks for Solar Cell Applications

Abstract

Texture etching of (100) and (111) single-crystal silicon using atomic hydrogen generated by the hot wire method was examined both by direct etching and etching through masks formed from SiO2 particles. Etching with SiO2 masks formed from colloidal silica solution produced a crater like texture on both oriented substrates. It was also found that the thickness of the mask region can be adjusted by changing the concentration of colloidal silica and by mixing different sizes of silica particles. The reflectivities of the substrates with textures generated by optimized mask formation were found to reach minima of about 13% for Si(100) and 19% for Si(111), which were lower than those of multicryastalline substrates with textures generated by alkali etching.