The investigation on the texture differences between p-type and n-type crystalline silicon wafers

Surface reflectivity is one of the important factors for solar cells. The anisotropic etching behavior of different types of monocrystalline silicon was studied in this paper. The etching rate is determined as a function of temperature, crystal orientation, and etchant composition. It is found that the etching rate of n-type silicon is faster than that of p-type silicon in the same corrosive solution. The reason is analyzed in this paper. For p-type silicon wafers, well-proportioned texturization was obtained in 2.0% NaOH(in mass, the same below) and 10% IPA aqueous solution at 80□ with 25 min, while for n-type wafers, the process time should be reduced to 20 min. The texturization was better when adding 3% Na₂SiO₃ in the solution, and the lowest reflectivity could be 9.5%.