METHOD OF TEXTURING SEMICONDUCTOR SUBSTRATES
Semiconductor substrates are cleaned and subsequently oxidized. After the semiconductor is oxidized it is textured to reduce incident light reflectance. The textured semiconductors can be used in the manufacture of photovoltaic devices.
1 . A method comprising:
a) cleaning a semiconductor substrate with an alkaline or acid silicon etching solution;
b) oxidizing a surface of the cleaned semiconductor substrate with an oxidizing composition comprising one or more oxidizing agents, the oxidizing composition has a pH greater than 7; and
c) texturing the oxidized semiconductor substrate.
2 . The method of claim 1 , wherein the one or more oxidizing agents are chosen from ozone, peroxides, perborates, percarbonates, hypochlorites, chlorates, perchlorates, hypobromites, bromates, hypoiodates, iodates, organic peracids and their salts, inorganic peracids and their salts.
3 . The method of claim 1 , wherein the oxidizing composition further comprises one or more chelating agents.
4 . The method of claim 1 , wherein the oxidizing composition further comprises one or more non-hydroxyl containing surfactants.
5 . The method of claim 1 , wherein the oxidizing composition further comprises one or more phosphonic acids.
6 . The method of claim 1 , wherein the texturing composition is an alkaline composition or an acid composition.
7 . The method of claim 6 , wherein the alkaline texturing composition comprises one or more quaternary ammonium hydroxides.
8 . The method of claim 6 , wherein the alkaline texturing composition comprises one or more alkoxylated glycols.
9 . The method of claim 1 , wherein the alkaline cleaning solution comprises one or more hydroxides.
10 . The method of claim 9 , wherein the alkaline cleaning solution further comprises one or more mid-range alkoxylates.