Investigation of texturization for monocrystalline silicon solar cells with different kinds of alkaline

In this paper, monocrystalline silicon was textured with different kind of etchants for solar cells, respectively. It was found that, only with sodium hydroxide (NaOH) or sodium acetate anhydrous (CH3COONa) solution, the textural results were very weak, resulting in high reflectance of silicon surface. However, if using the mixture solution of NaOH and CH3COONa, the reflectance was noticeably decreased. Moreover, the dependence of reflectance on the etching time showed that longer etching time was necessary for texturization in the NaOH + CH3COONa + H2O system. And it was also found that the addition of isopropyl alcohol (IPA) to this mixture solution had a detrimental effect on the texturization. All these results suggested that acetate (CH3COO-) plays a similar role as IPA for alkaline texturization, but they cannot coexist. Finally, the mechanisms of texturization with different kinds of etchant were discussed in detail. (C) 2004 Elsevier Ltd. All rights reserved.