JP5307759B2 - Cleaning agent for silicon wafer manufacturing process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detergent for silicon wafer producing processes expressing an excellent detergency to soil on a surface of a silicon wafer without impairing flatness of the silicon wafer in washing after slicing of a silicon ingot. <P>SOLUTION: The detergent for silicon wafer producing processes comprises (A) an anionic surfactant having a weight average molecular weight of 600-200,000, (B) at least one penetrant selected from the group consisting of (B1) alkylene oxide adducts of a higher alcohol and (B2) silicone-based surfactants, and (C) an alkali as the indispensable components. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a silicon wafer cleaning agent after slicing a silicon ingot in a silicon wafer manufacturing process.

As a method of slicing a silicon ingot in a silicon wafer manufacturing process, there are an inner peripheral blade method, a band saw method, a wire saw method, and the like. In these methods, a cutting fluid is used, but after slicing, the surface of the silicon wafer has a slurry state in which abrasive grains or silicon chips are mixed and dispersed in the cutting fluid, and the next step These need to be washed in order to move on.
However, the wire saw method currently used mainly has a narrow cutting margin of about 0.2 mm and a slurry state in which cutting fluid, abrasive grains, silicon chips, etc. are mixed and dispersed in the gap. Is in a clogged state and extremely difficult to clean.

  Conventionally, an alkali cleaning agent has been used for cleaning silicon wafers, but this cleaning agent has insufficient cleaning power, and has a problem that the surface of the silicon wafer is etched and roughened due to alkalinity. In order to solve this problem, a cleaning solution for a silicon wafer having a low etching rate, which is an alkaline aqueous solution containing a surfactant, has been disclosed (for example, see Patent Document 1). However, this cleaning solution has a problem that the cleaning performance is not sufficient.

JP-A-2001-40389

  An object of the present invention is to provide a cleaning agent for a silicon wafer manufacturing process that achieves excellent cleaning performance against dirt on the surface of a silicon wafer without impairing the flatness of the surface of the silicon wafer in cleaning after slicing the silicon ingot. There is.

［式（１）中、ｍ個のＲはメチレン基、エチレン基もしくはエチリデン基；ＡＯはオキシエチレン基またはオキシプロピレン基を表わす。ｍは平均値として１〜３の数；ｎは平均値として０〜３の数；ｋはアルキレンオキサイドの付加モル数を表わし５〜５０の数である。］ The inventors of the present invention have intensively studied to obtain a silicon wafer manufacturing process cleaning agent that solves the above-mentioned problems, and have reached the present invention.
That is, the present invention includes an anionic surfactant (A) having a weight average molecular weight of 600 to 200,000, an alkylene oxide adduct (B1) of a branched alcohol having 8 to 24 carbon atoms, and a silicone surfactant (B2). One or more penetrants selected from the group consisting of (B), alkali (C) and alkylene oxide adduct (D) represented by the following general formula (1) as essential components Process cleaning agent.

[In Formula (1), m R represents a methylene group, an ethylene group or an ethylidene group; AO represents an oxyethylene group or an oxypropylene group. m is a number from 1 to 3 as an average value; n is a number from 0 to 3 as an average value; k is the number of moles of alkylene oxide added and is a number from 5 to 50. ]

  The cleaning agent for a silicon wafer manufacturing process of the present invention can realize excellent cleaning performance against contamination of the silicon wafer surface without impairing the flatness of the silicon wafer surface in the silicon wafer manufacturing process.

The cleaning agent for manufacturing a silicon wafer according to the present invention comprises an anionic surfactant (A) having a weight average molecular weight of 600 to 200,000, a penetrant (B), and an alkali (C) as essential components. ) Is one or more selected from the group consisting of alkylene oxide adducts (B1) of higher alcohols and silicone surfactants (B2).

As the anionic surfactant (A) in the present invention, a sulfonic acid group having a weight average molecular weight of 600 to 200,000 or a salt thereof [hereinafter referred to as “acid group or salt thereof” is referred to as “acid (salt) group”]. Sometimes abbreviated. ] Anionic surfactant (A1) having a sulfate ester (salt) group, an anionic surfactant (A3) having a phosphate ester (salt) group, phosphonic acid ( Salt) group-containing anionic surfactant (A4), carboxylic acid (salt) group-containing anionic surfactant (A5), polysaccharides and derivatives thereof (A6), and the like.
Specific examples thereof include the following.

Anionic surfactant (A1) having a sulfonic acid (salt) group:
Polystyrene sulfonic acid, styrene / styrene sulfonic acid copolymer, poly [2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid], 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / Styrene copolymer, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / acrylamide copolymer, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / (meth) acrylic acid co Polymer, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / (meth) acrylic acid / acrylamide copolymer, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / styrene / Acrylamide copolymer, 2- (meth) acryloylamino-2,2-dimethyl eta Sulfonic acid / styrene / (meth) acrylic acid copolymer, naphthalene sulfonic acid formaldehyde condensate, methyl naphthalene sulfonic acid formaldehyde condensate, dimethyl naphthalene sulfonic acid formaldehyde condensate, anthracene sulfonic acid formaldehyde condensate, melamine sulfonic acid formaldehyde condensate And aniline sulfonic acid-phenol-formaldehyde condensates and the like and salts thereof;

Anionic surfactant (A2) having a sulfate (salt) group:
Poly [2-hydroxyethyl (meth) acrylate sulfate], 2-hydroxyethyl acrylate / 2-hydroxyethyl acrylate sulfate copolymer, 2-hydroxyethyl methacrylate / 2-hydroxyethyl methacrylate sulfate copolymer, poly [ 2-hydroxyethyl (meth) acrylate] sulfated product, poly [(meth) acryloyloxypolyoxyalkylene sulfate], (meth) acryloyloxypolyoxyalkylene sulfate / acrylic acid copolymer and cellulose, methylcellulose or ethylcellulose Sulfates of these and their salts;

Anionic surfactant (A3) having a phosphate ester (salt) group:
Poly [2-hydroxyethyl (meth) acrylate phosphate ester], 2-hydroxyethyl acrylate / 2-hydroxyethyl acrylate phosphate ester copolymer, 2-hydroxyethyl methacrylate / 2-hydroxyethyl methacrylate phosphate ester copolymer , Poly [2-hydroxyethyl (meth) acrylate] phosphoric acid ester, poly [(meth) acryloyloxypolyoxyalkylene phosphoric acid ester], (meth) acryloyloxy polyoxyalkylene phosphoric acid ester / acrylic acid copolymer And phosphoric acid ester of cellulose, methylcellulose or ethylcellulose, and salts thereof;

Anionic surfactant (A4) having a phosphonic acid (salt) group:
Poly [(meth) acryloyloxyethylphosphonic acid], 2-hydroxyethyl acrylate / acryloyloxyethylphosphonic acid copolymer and 2-hydroxyethyl methacrylate / methacryloyloxyethylphosphonic acid copolymer, naphthalenephosphonic acid formaldehyde condensate, methyl Naphthalene phosphonic acid formaldehyde condensate, dimethyl naphthalene phosphonic acid formaldehyde condensate, anthracene phosphonic acid formaldehyde condensate, aniline phosphonic acid-phenol-formaldehyde condensate and the like, and salts thereof;

Anionic surfactant (A5) having a carboxylic acid (salt) group:
Poly (meth) acrylic acid, (meth) acrylic acid-maleic acid copolymer, (meth) acrylic acid-itaconic acid copolymer, (meth) acrylic acid-fumaric acid copolymer, (meth) acrylic acid / acetic acid Vinyl copolymer, 2-hydroxyethyl methacrylate / (meth) acrylic acid copolymer, carboxymethylated product of poly [2-hydroxyethyl (meth) acrylate]}, carboxymethylcellulose, carboxymethylmethylcellulose, carboxymethylethylcellulose, benzoic acid Formaldehyde condensates and benzoic acid-phenol-formaldehyde condensates and their salts;

Polysaccharides and their derivatives (A6):
Hydroxyethylcellulose, cationized cellulose, hydroxymethylcellulose, hydroxypropylcellulose, guar gum, cationized guar gum, xanthan gum, alginate, cationized starch, etc., poval and phosphate esters [phytic acid, di (polyoxyethylene) alkyl ether phosphate and Tri (polyoxyethylene) alkyl ether phosphoric acid, etc.].

  The counter ion when the anionic surfactant (A) forms a salt is not particularly limited. For example, alkali metal salt (sodium salt, potassium salt, etc.), ammonium salt, primary amine salt (for example, methylamine, Alkylamines such as ethylamine and butylamine, monoethanolamine and guanidine), secondary amine salts (eg, dialkylamines such as dimethylamine, diethylamine and dibutylamine and diethanolamine), tertiary amine salts [eg, trimethylamine, triethylamine and tributylamine Trialkylamine, triethanolamine and 1,4-diazabicyclo [2.2.2] octane (DABCO)], amidine salt [1,8-diazabicyclo [5.4.0] -7-undecene (DBU) And 1,5-di Zabishikuro [4.3.0] -5-nonene (DBN), etc.] as well as quaternary ammonium salts (tetraalkyl ammonium salts and the like).

  Among these (A), (A1) is preferable from the viewpoint of dispersibility of abrasive grains and silicon chips, and naphthalenesulfonic acid formaldehyde condensates and salts thereof are more preferable.

  The weight average molecular weight of (A) is usually from 600 to 200,000, preferably from 800 to 150,000, more preferably from 1,000 to 100, from the viewpoint of dispersibility of abrasive grains and silicon chips and low foamability. , 000.

The weight average molecular weight in the present invention is measured by gel permeation chromatography at 40 ° C. using polyethylene oxide as a reference substance.
For example, apparatus main body: HLC-8120 (manufactured by Tosoh Corporation),
Column: TSKgel α6000, G3000 PWXL, manufactured by Tosoh Corporation
Detector: Differential refractometer detector built in the device body
Eluent: 0.5% sodium acetate / water / methanol (volume ratio 70/30),
Eluent flow rate: 1.0 ml / min,
Column temperature: 40 ° C., sample: 0.25% eluent solution,
Injection volume: 200 μl, standard substance: TSK TANDARD POLYETHYLENE OXIDE manufactured by Tosoh Corporation
Data processing software: GPC-8020 model II (manufactured by Tosoh Corporation)].

Specific examples of the penetrant (B) in the present invention include higher alcohol AO adducts (B1) [hereinafter abbreviated as alkylene oxide “AO”] and silicone surfactants (B2).
(1) AO adduct of higher alcohol (B1)
AO added to an alcohol having a straight chain saturated or unsaturated hydrocarbon group having 8 to 24 carbon atoms (B11), or an alcohol having a saturated or unsaturated hydrocarbon group having 8 to 24 branches. Added one (B12) and the like.

Specific examples of the alcohol constituting (B11) include n-octanol, n-decyl alcohol, n-undecyl alcohol, n-dodecyl alcohol, n-tridecyl alcohol, n-tetradecyl alcohol, and n-pentadecyl alcohol. N-heptadecyl alcohol, n-octadecyl alcohol, n-nonadecyl alcohol, n-eicosyl alcohol, heneicosyl alcohol, docosyl alcohol, tricosyl alcohol, tetracosyl alcohol and the like.

Specific examples of the alcohol constituting (B12) include 2-ethylhexyl alcohol, isodecyl alcohol, isoundecyl alcohol, isododecyl alcohol, isotridecyl alcohol, isotetradecyl alcohol, isopentadecyl alcohol, and isoheptadecyl alcohol. , Isooctadecyl alcohol, isononadecyl alcohol, isoeicosyl alcohol, isohenecosyl alcohol, isodocosyl alcohol, isotricosyl alcohol, and isotetracosyl alcohol.

The alkylene oxide (AO) added to these alcohols is sometimes referred to as ethylene oxide [hereinafter referred to as “EO”. ], Propylene oxide [hereinafter sometimes abbreviated as “PO”. ], Butylene oxide, styrene oxide and the like. Two or more of these can be added, and the addition format may be either random or block, and the order of addition is not limited.
Specific examples of the higher alcohol AO adduct include n-octanol EO 4 mol adduct, n-decyl alcohol EO (1 mol) / PO (1 mol) random adduct, n-undecyl alcohol EO 3 mol adduct, Examples include 2-ethylhexyl alcohol EO 8 mol adduct, isodecyl alcohol EO 7 mol adduct, isoundecyl alcohol EO 7 mol / PO 1 mol block adduct, and the like.

  As the higher alcohol AO adduct (B1), an alcohol AO adduct (B12) having a saturated or unsaturated hydrocarbon group having 8 to 24 carbon atoms is preferred.

(2) Silicone surfactant (B2)
Examples include polyether-modified silicone, amino-modified silicone, carboxyl-modified silicone, and polyether-modified silicone is preferred from the viewpoint of liquid stability. Moreover, you may use 2 or more types together.

  As the alkali (C), inorganic alkali (lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, etc.), ammonia, quaternary ammonium salt (tetramethylammonium hydroxide, ethyltrimethyl hydroxide) Ammonium, tetraethylammonium hydroxide, triethylmethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, tetrahexylammonium hydroxide, hydroxyethyltrimethylammonium hydroxide, triethylhydroxyethylammonium hydroxide , Dihydroxyethyldimethylammonium hydroxide, trihydroxyethylmethylammonium hydroxide, etc.), and these include one or more It may be used in conjunction seen.

  Furthermore, it is preferable to contain the alkylene oxide adduct (D) represented by the following general formula (1) in the cleaning agent for manufacturing a silicon wafer of the present invention for the purpose of further improving the cleaning performance.

[In the formula, m R represents a methylene group, an ethylene group or an ethylidene group; AO represents an oxyethylene group or an oxypropylene group. m is a number from 1 to 3 as an average value; n is a number from 0 to 3 as an average value; ]

M R in the above chemical formula represents a methylene group, an ethylene group or an ethylidene group, and an ethylene group is preferable.
m is an average value of 1 to 3, n is an average value of 0 to 3, and the degree of styrenization or benzylation represented by m + n is usually 1 to 4, preferably 1 to 3. .

AO represents an oxyethylene group or an oxypropylene group, and these may be used in combination.
From the viewpoint of storage stability as an aqueous solution, it is preferably hydrophilic, and an oxyethylene group and a combination of an oxyethylene group and an oxypropylene group are preferable.
k represents the number of added moles of alkylene oxide, and is a number of 5 to 50, preferably 10 to 40.

  Examples of the alkylene oxide adduct (D) represented by the above general formula include an AO adduct (D1) of styrenated phenol and an AO adduct (D2) of benzylated phenol.

  Styrenated phenol AO adduct (D1) includes styrenated phenol EO adduct, styrenated phenol PO adduct, styrenated phenol EO / PO random adduct, styrenated phenol PO / EO block adduct. Etc.

  As the AO adduct (D2) of benzylated phenol, EO adduct of benzylated phenol, PO adduct of benzylated phenol, EO / PO random adduct of benzylated phenol, PO / EO block adduct of benzylated phenol Etc.

The alkylene oxide adduct (D) of the present invention can be produced by combining the following known Friedel-Craft reaction and alkylene oxide addition reaction.
(A) Friedel-Craft Reaction Styrene or benzyl chloride is added to phenol by Friedel-Craft reaction.
As the catalyst in (a), aluminum chloride, zinc chloride or activated clay can be used. Examples of the reaction conditions include those described in JP-B-50-25526.
The obtained crude product is preferably purified by filtration, extraction or the like.

(B) Addition reaction of alkylene oxide AO is added to the hydroxyl group in the Friedel-Craft reaction product of styrene or benzyl chloride obtained in (a) above to phenol.
There is a method in which Friedel-Craft reaction product is charged into a pressure reactor and AO is injected in the presence of no catalyst or catalyst.
Examples of the catalyst include alkali catalysts, such as hydroxides of alkali metals (lithium, sodium, potassium, cesium, etc.); acids [perhalogen acids (perchloric acid, perbromic acid, periodic acid), sulfuric acid, phosphoric acid, nitric acid, etc. , Preferably perchloric acid] and salts thereof [preferably salts of divalent or trivalent metals (Mg, Ca, Sr, Ba, Zn, Co, Ni, Cu, Al)].
The reaction temperature is usually 50 to 150 ° C., and the reaction time is usually 2 to 20 hours.
When two or more types of AO are used in combination, block addition (chip type, balance type, active secondary type, etc.), random addition, or a mixed system of both may be used.
After completion of the AO addition reaction, the catalyst is preferably removed and purified by neutralization and treatment with an adsorbent.

  The cleaning agent for a silicon wafer production process of the present invention may contain an anionic surfactant (E) other than the anionic surfactant (A) in order to remove oil stains and the like.

  Examples of such anionic surfactant (E) include sulfated fatty acid salts, sulfonated fatty acid salts, phosphate ester salts, sulfate esters of fatty acid esters, sulfonate ester salts of fatty acid esters, higher alcohol ether-substituted acetic acid. Salt, fatty acid and amino acid condensate, fatty acid amide alkylol sulfate ester, fatty acid amide alkylated sulfonate, sulfosuccinate ester salt, alkylphenol sulfonate, alkyl diphenyl ether sulfonate, alkyl naphthalene sulfonate, Alkyl benzimidazole sulfonate, amide ether carboxylic acid or its salt, ether carboxylic acid or its salt, N-acyl-N-methyltaurine or its salt, amide ether sulfuric acid or its salt, N-acyl glutamic acid or its salt, N -Amide Til-N-hydroxyethylacetic acid or a salt thereof, acyloxyethanesulfonic acid or a salt thereof, N-acyl-β-alanine or a salt thereof, N-acyl-N-carboxyethyltaurine or a salt thereof, N-acyl-N-carboxyl Examples include ethyl glycine or a salt thereof, and alkyl or alkenylaminocarbonylmethyl sulfate or a salt thereof.

  The cleaning agent for a silicon wafer production process of the present invention may further contain other additives such as a pH adjusting agent, a buffering agent and an antifoaming agent as long as the effect of the cleaning agent is not impaired.

  Examples of the pH adjuster include acids such as hydrochloric acid, sulfuric acid, nitric acid and sulfamic acid, and these may be used alone or in combination of two or more.

  Buffering agents for fine adjustment of pH include C1-C10 organic acids having a buffering action (acetic acid, formic acid, gluconic acid, glycolic acid, tartaric acid, fumaric acid, levulinic acid, valeric acid, maleic acid and mandel Acid), inorganic acids (phosphoric acid, boric acid, etc.) and salts thereof. These may be used alone or in combination of two or more.

  Examples of the antifoaming agent include silicone antifoaming agents [antifoaming agents containing dimethyl silicone, fluorosilicone, polyether silicone and the like as constituents] and the like. These may be used alone or in combination of two or more.

  The cleaning agent for a silicon wafer production process of the present invention may further contain water, particularly ion-exchanged water (conductivity: 0.2 μS / cm or less) or ultrapure water (electric resistivity: 18 MΩ · cm or more).

Content at the time of use of the anionic surfactant (A) in the cleaning agent for silicon wafer production process of the present invention is usually 0.1 to 15% by weight, preferably 1 to 10% by weight.
If it is less than 0.1% by weight, the detergency is low, and if it exceeds 15% by weight, the viscosity of the cleaning agent becomes too high and handling becomes difficult.

The content of the penetrant (B) in the cleaning agent during use is usually 0.01 to 10% by weight, preferably 0.1 to 5% by weight.
If it is less than 0.01% by weight, the detergency is low, and if it exceeds 5% by weight, no significant improvement in detergency is observed.

The content of the alkali (C) in the detergent during use is usually 0.05 to 15% by weight, preferably 0.1 to 10% by weight.
If it is less than 0.05% by weight, the cleaning power is low, and if it exceeds 15% by weight, the flatness of the wafer surface is impaired.

The content of the alkylene oxide adduct (D) during use in the cleaning agent is usually 0.01 to 10% by weight, preferably 0.1 to 5% by weight.
If it is less than 0.01% by weight, the detergency is low, and if it exceeds 10% by weight, no significant improvement in detergency is observed.

  When using a cleaning agent for a silicon wafer manufacturing process as a cleaning liquid, it is usually diluted with water, ion-exchanged water (conductivity: 0.2 μS / cm or less) or ultrapure water (electric resistivity: 18 MΩ · cm or more). The concentration of the active ingredient in the cleaning liquid for the silicon wafer production process in the cleaning liquid is preferably 0.1 to 15%, more preferably 0.5 to 10%, from the viewpoint of workability and cost.

The pH at 25 ° C. during use of the cleaning agent for the silicon wafer production process of the present invention is 7.0 to 14.0, preferably 8.0 to 14 from the viewpoint of achieving both cleaning properties and flatness of the silicon wafer surface. .0.
If the pH is less than 7.0, the detergency is insufficient.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this. Unless otherwise specified, “parts” means “parts by weight” below. In addition, Examples 1-3 in the following are reference examples.

[Production Example of AOA (D-1) of Styrenated Phenol]
An autoclave was charged with 208 parts by weight (1 mole) of styrenated phenol (degree of styrenation 2 moles) and 0.45 part of potassium hydroxide. After nitrogen substitution, the temperature was 100 to 160 ° C., the gauge pressure was 0 to 8 kg / cm ^2. Under these conditions, 399 parts by weight (10 moles) of PO and 393 parts by weight of EO (13 moles) were added to effect addition polymerization. Thereafter, the catalyst potassium hydroxide was removed by adsorption with an adsorbent to obtain 1000 parts of a styrenated phenol AOA compound (D-1) used in Examples 4 and 5.

The cleaning agents of Examples and Comparative Examples were blended at the ratio shown in Table 1. The total weight part was adjusted to 100 parts by weight with ion-exchanged water.
In addition, the following were used for the anionic surfactant (A-1), penetrant (B-1), penetrant (B-2), and penetrant (B′-1) in the table.
Anionic surfactant (A-1): Naphthalenesulfonic acid formalin condensate penetrant (B-1): Isodecyl alcohol EO 6 mol adduct penetrant (B-2): Shin-Etsu Chemical "X22-904"
Penetration agent (B′-1): “Sanmorin OT-70” (sodium dioctylsulfosuccinate) manufactured by Sanyo Chemical Industries

Furthermore, each cleaning agent was diluted 50 times with ion-exchanged water to prepare a cleaning solution, and performance evaluation of cleaning property, permeability, and flatness was performed by the following methods.
<Detergency>
25 parts of SiC abrasive grains (GC-1000 particle size: about 11.5 μm manufactured by Fujimi Incorporated), 25 parts of silicon powder (particle size: about 1 μm manufactured by High Purity Chemical Laboratory), polyoxyethylene glycol (number A slurry mixed with 50 parts of an average molecular weight of 300) is used as a soil for a detergency test.
Place 0.4 g of the slurry on one side of one silicon wafer (diameter 6 cm, disk shape 0.2 mm in thickness), and sandwich another silicon wafer with a gap of 0.2 mm between the silicon wafers. Then, another contaminated silicon wafer (0.5 cm × 0.5 cm, thickness 0.2 cm) was used as a spacer and the whole was fixed with a clip to prepare a contaminated substrate for testing.
200 g of the cleaning liquids of Examples and Comparative Examples were placed in a 200 ml glass beaker, and the prepared contaminated substrate was immersed and left at 40 ° C. for 15 minutes for cleaning. After cleaning, the clip was removed, the silicon wafer was taken out of the contaminated substrate and dried, and then the dirt between the silicon substrates was visually confirmed, and the cleaning property was evaluated according to the following evaluation points.

A: Almost completely removed (area where dirt remains is less than 5%).
○: Almost clean (area of remaining dirt is 5 to 10%).
Δ: Some particles remain (the area where dirt remains is 10 to 20%).
X: Not cleaned (area where dirt remains is over 20%).

<Penetration>
Fully automatic contact angle meter [DM-700, manufactured by Kyowa Interface Science Co., Ltd.] is applied to a silicon wafer (5 cm × 10 cm, thickness 0.2 cm) immediately after being thoroughly rinsed with ultrapure water, blown with nitrogen and dried. Using, the contact angle (25 degreeC, 10 second after) with respect to a washing | cleaning liquid was measured, and the washability was evaluated according to the following evaluation points.

○: Contact angle is less than 40 degrees Δ: Contact angle is less than 40 to 50 degrees ×: Contact angle is 50 degrees or more

<Flatness>
Take 10g of the cleaning solution in a 20ml glass container, adjust the temperature to 40 ° C, put a silicon wafer (2cm x 2cm, thickness 0.2cm), immerse and stand at 40 ° C for 5 hours, and then use tweezers After removing the cleaning solution by thoroughly rinsing with ultrapure water, the wafer was blown with nitrogen at 25 ° C. to dry the wafer, and then the surface roughness (Ra: arithmetic average surface roughness) was measured by an atomic force microscope. (Measured using S-I Nano Technology Co., Ltd., E-Sweep). The smaller the Ra, the better the surface flatness.
Using a silicon wafer that was not immersed in the cleaning liquid as a blank, the surface roughness was evaluated according to the following calculation formula for evaluation points.

Evaluation point N = (Ra of wafer after immersion cleaning) / (Ra of blank wafer)
○: 1.0 ≦ N <1.2
Δ: 1.2 ≦ N <1.4
×: 1.4 ≦ N

  From the results of Table 1, Examples 1 to 5 are satisfactory in both cleanability and flatness, but if the specific penetrant (B) of the present invention is not added, the detergency is insufficient and cleaning is performed. If the amount of alkali added is increased to compensate for the property, the flatness of the wafer is impaired.

The cleaning agent for the silicon wafer manufacturing process of the present invention is not only a cleaning agent for a silicon wafer after slicing, but also a cleaning agent for a silicon wafer after polishing / grinding and a disk for storage media made of aluminum or glass after polishing / grinding. Is extremely effective.

Claims (3)

1 selected from the group consisting of an anionic surfactant (A) having a weight average molecular weight of 600 to 200,000, an alkylene oxide adduct (B1) of a branched alcohol having 8 to 24 carbon atoms, and a silicone surfactant (B2). silicon wafer manufacturing process for cleaning agent characterized in that the alkylene oxide adduct (D) as an essential component represented by species or more penetration agents (B), a alkaline (C) and the following general formula (1).

[In Formula (1), m R represents a methylene group, an ethylene group or an ethylidene group; AO represents an oxyethylene group or an oxypropylene group. m is a number from 1 to 3 as an average value; n is a number from 0 to 3 as an average value; k is the number of moles of alkylene oxide added and is a number from 5 to 50. ] The cleaning agent for a silicon wafer production process according to claim 1, wherein the anionic surfactant (A) is a naphthalenesulfonic acid formaldehyde condensate or a salt thereof.   The silicon wafer production according to claim 1 or 2, wherein the silicone surfactant (B2) is at least one silicone surfactant selected from the group consisting of polyether-modified silicone, amino-modified silicone and carboxyl-modified silicone. Cleaning agent for process.