Effect of temperature in electrochemical texturising of multi-crystalline silicon in KOH solution

Abstract

In this paper we present the study of electrochemical etching of silicon in KOH solutions to improve texturisation and reflection properties of p–type multi–crystalline silicon. The influence of etching temperature on surface morphology and reflection properties of the silicon wafers has been investigated. The results of the study showed that etching at high temperatures formed isotropic textured concaves on the silicon surface which is similar to the effect of acidic etching. Etching at room temperature resulted in formation of a uniform nano–porous texture and lowest reflectance. With optimised etching conditions, the total reflectance of the textured surface reduced below 25%. These results can be utilised in further studies to improve the efficiency of solar cells based on multi–crystalline silicon.