Compositions and Methods for Texturing of Silicon Wafers
Pre-texturing composition for texturing silicon wafers having one or more surfactants. Methods of texturing silicon wafers having the step of wetting said wafer with a pre-texturing composition having one or more surfactants followed by a texturing step.
1 . A pre-texturing composition for texturing silicon wafers, wherein said composition comprises one or more surfactants.
2 . The pre-texturing composition of claim 1 comprising one or more anionic, cationic, non-ionic, and zwitterionic surfactants or mixtures thereof.
3 . The pre-texturing composition of claim 1 wherein said one or more surfactants comprise at least one surfactant selected from the group consisting of alkylphenol ethoxylates, polyoxyethylenated polyoxypropylene glycols, polyoxyethylenated mercaptans, long chain carboxylic acid esters, glyceryl and polyglyceryl esters of natural fatty acids, propylene glycol esters, sorbitol esters, polyoxyethylenated sorbitol esters, polyoxyethylene glycol esters, polyoxyethylenated fatty acids, alkanol amides, acetylenic glycols, polyoxyethylenated silicones, n-alkylpyrrolidones, alkylpolyglycosides, silicone surfactants, fluorochemical surfactants, octyl and nonyl phenol ethoxylates, acetylenic diol type of surfactants, alcohol ethoxylates, phenyl ethoxylates, amine ethoxylates, glucosides, glucamides, polyethylene glycols, and poly(ethylene glycol-co-propylene glycol) or mixtures thereof.
4 . The pre-texturing composition of claim 1 wherein said one or more surfactants comprise at least one surfactant selected from the group consisting of straight chain fatty acids and/or salts thereof, coconut oil fatty acid derivatives, tall oil acid derivatives, sarcosides, aceylated polypeptides, lignin sulfonates, N-acyl-n-alkyltaurates, petroleum sulfonates, paraffin sulfonates, sulfosuccinate esters, alkylnapthalenesulfonates, isethionates, sulfuric acid esters, sulfated linear primary alcohols, sulfated polyoxyethylenated straight chain alcohols, sulfated triglyceride oils, phosphoric and polyphosphoric acid esters and perfluorinated anionics, or mixtures thereof.
5 . The pre-texturing composition of claim 1 , wherein said one or more surfactants comprises at least one surfactant selected from the group consisting of long chain amines and their salts, diamines and polyamines and their salts, quaternary ammonium salts, polyoxyethylenated long chain amines, quaternized polyoxyethylenated (POE) long chain amines, amine oxides, N-alkyl derivatives of simple amino acids, glycine, betaine and amino propionic acids, imidazolines, and sulfobetaines, or mixtures thereof.
6 . The pre-texturing composition of claim 1 wherein said one or more surfactants comprise one or more of the surfactants selected from the group consisting of linear alkylbenzenesulfonates (LAS), secondary alylbenzenesulfonate, fatty alcohol sulfates (FAS), secondary alkanesulfonates (SAS), fatty alcohol ether sulfates (FAES), α-olefin sulfonates, alkyl betaine surfactant and silicone surfactants.
7 . The pre-texturing composition of claim 1 wherein said one or more surfactants comprise at least one selected from the group consisting of secondary alkane sulfate, lauryl sulfate, lauryl ether sulfate, and N-(Alkyl C10-C16)-N,N-dimethylglycine betaine or mixtures thereof.
8 . The pre-texturing composition of claim 7 further comprising one or more organic acids, one or more optional bases, one or more optional anti-foaming agents and one or more optional corrosion inhibitors.
9 . The pre-texturing composition of claim 1 wherein said one or more surfactants comprises surfactant having the following structure:
where R 1 and R 2 are independently alkyl groups or phenyl groups comprising 1-20 carbons and X is hydrogen or a cation selected from the group consisting of Na, K, tetramethyl ammonium, tetraethyl ammonium, triethanol amine, and ammonium.
10 . The pre-texturing composition of claim 9 further comprising silicone surfactant.
11 . The pre-texturing composition of claim 1 wherein said surfactant comprises one or more secondary alkane sulfonate surfactants.
12 . The pre-texturing composition of claim 1 wherein said one or more surfactants are present in the composition from 0.01 wt % to 30 wt % of a total weight of the composition and said composition further comprises water.
13 . A method of texturing a silicon wafer comprising the step of:
wetting said wafer with a pre-texturing composition comprising one or more surfactants.
14 . A method of texturing a silicon wafer comprising the step of:
wetting said wafer with a pre-texturing composition comprising one or more anionic, cationic, non-ionic and zwitterionic surfactants or mixtures thereof.
15 . The method of claim 13 wherein said one or more surfactants comprises at least one surfactant selected from the group consisting of linear alkylbenzenesulfonates (LAS), secondary alkylbenzenesulfonate, fatty alcohol sulfates (FAS), secondary alkanesulfonates (SAS), fatty alcohol ether sulfates (FAES), α-olefin sulfonates, alkyl betaine surfactant and silicone surfactants, or mixtures thereof.
16 . The method of claim 14 further comprising the step of:
wetting said wafer with an etching composition after said step of wetting said wafer with a pre-texturing composition.
17 . The method of claim 16 further comprising between said wetting steps, a step of rinsing said wafer with a rinsing solution.
18 . The method of claim 16 further comprising prior to either wetting step the step of wetting said wafer with a saw damage removal composition or a pre-cleaning composition.
19 . The method of claim 18 where said etching composition is substantially free of surfactant.