JP5974970B2 - Wafer cleaning composition and wafer cleaning method - Google Patents

Description

  The present invention relates to a quaternary ammonium hydroxide compound and a production method thereof, a wafer cleaning composition, and a wafer cleaning method.

In recent years, various types of substrates have been miniaturized and highly integrated. For example, in semiconductor mounting, higher density and larger capacity are realized by three-dimensional mounting. The three-dimensional semiconductor mounting technology is a semiconductor manufacturing technology in which one semiconductor chip is thinned and further laminated in multiple layers while being connected by a through silicon via (TSV).
In order to realize this, an electrode forming step is required in which the substrate on which the semiconductor circuit is formed is thinned by back surface grinding, and further, an electrode or the like containing TSV is formed on the back surface.

  When thinning, a system that can withstand processing such as a back grinding process and a back electrode forming process has been proposed by bonding a substrate on which a semiconductor circuit is formed to a support substrate such as silicon or glass via an adhesive. However, it is necessary to easily peel off the support substrate after the step, and after the support substrate is peeled off, the adhesive remaining on the substrate surface on which the semiconductor circuit is formed is removed, and finally the thin film semiconductor substrate surface is cleaned. There is a need. Also, in the processing step, the adhesive may require a high temperature of 150 ° C. or higher, and the adhesive is also required to have heat resistance. Therefore, a silicone-based adhesive is used, but only an organic solvent that dissolves the adhesive when cleaning the substrate surface. In this cleaning, it is difficult to remove the adhesive sufficiently, and in some cases, problems such as poor adhesion of the sealing material may occur in the subsequent manufacturing process.

  Therefore, a cleaning composition that can sufficiently remove the remaining adhesive without corroding the substrate surface in a short time is desired, but the substrate surface contaminated with the silicone component of the adhesive can be sufficiently cleaned in a short time. No cleaning composition has been found so far.

  As prior art related to the present invention, Japanese Patent Application Laid-Open No. 2005-145924 (Patent Document 1), Japanese Patent Application Laid-Open No. 2012-208325 (Patent Document 2), and Japanese Patent Application Laid-Open No. 2013-010888 (Patent Document 3). Can be mentioned.

JP 2005-145924 A JP 2012-208325 A JP 2013-010888 A

  The present invention has been made in view of the above circumstances, and provides a novel quaternary ammonium hydroxide compound suitable for cleaning a wafer in which an adhesive remains, a manufacturing method thereof, a wafer cleaning composition, and a wafer cleaning method. For the purpose.

  As a result of intensive studies on the quaternary ammonium hydroxide compound, the present inventor has found that the novel compounds represented by the formulas (1) and (2) described below can solve the above problems, and completes the present invention. It came to.

（式中、Ｒ¹はメチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、イソブチル基、ｓｅｃ−ブチル基又はｔｅｒｔ−ブチル基、Ｒ²、Ｒ³、Ｒ⁴、Ｒ⁵、Ｒ⁶、Ｒ⁷はそれぞれ水素原子又は炭素数１〜４の一価の脂肪族炭化水素基である。）
〔２〕 Ｒ¹がメチル基又はエチル基である〔１〕記載のウェハ洗浄用組成物。
〔３〕 Ｒ¹がエチル基である〔２〕記載のウェハ洗浄用組成物。
〔４〕 Ｒ²が水素原子又はメチル基であり、Ｒ³、Ｒ⁴、Ｒ⁵、Ｒ⁶、Ｒ⁷がそれぞれ水素原子である〔１〕〜〔３〕のいずれかに記載のウェハ洗浄用組成物。
〔５〕 更に、有機溶剤を含む〔１〕〜〔４〕のいずれかに記載のウェハ洗浄用組成物。
〔６〕 上記第四級アンモニウムヒドロキサイド化合物の濃度が０．１〜１０質量％である〔１〕〜〔５〕のいずれかに記載のウェハ洗浄用組成物。
〔７〕 〔１〕〜〔６〕のいずれかに記載のウェハ洗浄用組成物を用いて、接着剤が付着したウェハを洗浄することを特徴とするウェハ洗浄方法。
That is, the present invention provides a c E c cleaning composition and wafer cleaning methods described below.
[1] A wafer cleaning composition comprising a quaternary ammonium hydroxide compound represented by the following formula (1) or (2) and water .

(In the formula, R ¹ is methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group or tert-butyl group , R ² , R ³ , R ⁴ , R ^5. , R ⁶ and R ⁷ are each a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 4 carbon atoms.)
[2] The wafer cleaning composition according to [1], wherein R ¹ is a methyl group or an ethyl group.
[3] The wafer cleaning composition according to [2], wherein R ¹ is an ethyl group.
[4] For wafer cleaning according to any one of [1] to [3], wherein R ² is a hydrogen atom or a methyl group, and R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are each a hydrogen atom . Composition .
[ 5 ] The wafer cleaning composition according to any one of [ 1 ] to [4], further comprising an organic solvent.
[ 6 ] The wafer cleaning composition according to any one of [ 1 ] to [ 5 ] , wherein the concentration of the quaternary ammonium hydroxide compound is 0.1 to 10% by mass.
[ 7 ] A wafer cleaning method comprising: cleaning a wafer to which an adhesive is attached using the wafer cleaning composition according to any one of [ 1 ] to [ 6 ].

  According to the present invention, a novel quaternary ammonium hydroxide compound that can be easily produced from industrially available raw materials can be provided, and a wafer cleaning composition containing the compound and water can be used. The surface of the substrate contaminated by the adhesive and particularly contaminated with the silicone component can be sufficiently cleaned in a short time.

Hereinafter, the present invention will be described in more detail.
(Quaternary ammonium hydroxide compound)
The quaternary ammonium hydroxide compound of the present invention is a quaternary ammonium hydroxide compound represented by the following formula (1) or formula (2), and exhibits strong basicity when dissolved in water at room temperature (20 ° C.). It is a solid compound.

Here, in Formula (1) or Formula (2), R ¹ is a monovalent aliphatic hydrocarbon group having 1 to 4 carbon atoms, R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ^7. Each represents a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 4 carbon atoms. Examples of R ¹ include linear or branched alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl groups. Of these, methyl and ethyl are preferable, and ethyl is particularly preferable. Examples of R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , and R ⁷ include a hydrogen atom, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl group, and the like. In view of availability of raw materials, R ² is preferably a hydrogen atom or a methyl group, and R ³ , R ⁴ , R ⁵ , R ⁶ , or R ⁷ is preferably a hydrogen atom.

  Specific examples of the compound of the formula (1) include those having the following structural formula.

  Specific examples of the compound of the formula (2) include those having the following structural formula.

(Method for producing quaternary ammonium hydroxide compound)
As a method for producing a quaternary ammonium hydroxide compound of the formula (1) or the formula (2), for example, an alkyl halide and a cyclic diamine compound represented by the following formula (3) are reacted and treated with a strong base. Can be manufactured.

Here, in the formula (3), R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are each a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 4 carbon atoms. Examples of R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ include a hydrogen atom, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl group, etc. In view of the availability of raw materials, R ² is preferably a hydrogen atom or a methyl group, and R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are preferably a hydrogen atom.

  Examples of the alkyl halide used in the present invention include methyl bromide, methyl iodide, ethyl chloride, ethyl bromide, ethyl iodide, n-propyl chloride, isopropyl chloride, n-propyl bromide, and n-propyl iodide. N-butyl chloride, isobutyl bromide, n-butyl iodide, isopropyl iodide, n-butyl bromide, isobutyl iodide, sec-butyl iodide, tert-butyl iodide, and the like.

  Depending on the reaction molar ratio of the compound of formula (3) and the alkyl halide, a single compound of formula (1) or a mixture of the compound of formula (1) and the compound of formula (2) can be produced. . For example, a single compound of the formula (1) can be produced by reacting 2.0 mol or more of an alkyl halide with 1.0 mol of the compound of the formula (3). At that time, the excess alkyl halide after the reaction may be removed by distillation. When the halogenated alkyl is reacted at less than 2.0 mol, a mixture of the compound of the formula (1), the compound of the formula (2) and the raw material of the compound of the formula (3) is obtained. Even if such a mixture is used as it is, a wafer cleaning effect as a wafer cleaning composition can be obtained. In addition, it is preferable that alkyl halide shall be 1.0 mol or more with respect to 1.0 mol of compounds of Formula (3).

  The reaction temperature in this reaction is arbitrary, but is preferably from room temperature (20 ° C.) to about 150 ° C. Although the reaction time is arbitrary, the reaction is completed in about 30 minutes to 48 hours. Moreover, when performing this reaction, although the use of a reaction solvent is arbitrary, a reaction solvent is usually used. Examples of the solvent used include alcohols such as water, methanol and ethanol, polar solvents such as acetonitrile, N, N-dimethylformaldehyde and dimethyl sulfoxide, aromatic hydrocarbons such as toluene and xylene, hexane, heptane and decane. Examples include aliphatic hydrocarbons.

  The quaternary ammonium salt produced by reacting an alkyl halide with the compound of formula (3) has an anion of chloride ion, bromide ion or iodide ion. In order to achieve this, an ion exchange treatment with a strong base is required. This ion exchange processing method can be performed by a conventionally known general method. The reaction temperature in that case is arbitrary and is about 0-50 degreeC, and what is necessary is just to perform normally at room temperature (20 degreeC). Also, the reaction time is arbitrary and is about 30 minutes to 24 hours.

  Examples of the strong base used include sodium hydroxide, potassium hydroxide and barium hydroxide. By adding such a strong base, sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, potassium iodide, and the like are produced. These may be removed by filtration. The amount of the strong base to be added may be approximately the same number of moles as the reacted alkyl halide. After completion of the reaction, the reaction solvent is distilled off and concentrated, or the concentrated and dried solid is further recrystallized and purified with an appropriate solvent, whereby the quaternary ammonium hydroxide compound of the present invention can be obtained.

(Wafer cleaning composition)
In the present invention, the compound represented by the formula (1) can be used alone as a wafer cleaning composition, and the reaction product is represented by the compound represented by the formula (1) and the formula (2). It is also possible to use a mixture of the compounds represented as a wafer cleaning composition. In the case of a mixture, although it is not particularly limited, the compound of the formula (2) is contained in an amount of more than 0 mol% and 80 mol% or less, more preferably more than 0% and 60 mol% or less with respect to the compound of the formula (1). Also good. At that time, the compound of the formula (3) may be contained as a raw material residue.

  That is, the composition for wafer cleaning according to the present invention is a composition comprising the compound represented by the above formula (1) or the compound represented by the formula (2) and water. Alternatively, an organic solvent may be further included.

  The concentration of the quaternary ammonium hydroxide compound in the wafer cleaning composition may be 0.1 to 10.0% by mass, and particularly preferably 0.1 to 5.0% by mass. If the concentration of the quaternary ammonium hydroxide compound is less than 0.1% by mass, the detergency may be insufficient, and if it exceeds 10.0% by mass, the substrate may be corroded.

  The amount of water added in the wafer cleaning composition is arbitrary, but is 90.0 to 99.9% by mass when no organic solvent is used, and preferably 0.1% when used in combination with an organic solvent. To 99.8% by mass, more preferably 0.1 to 50.0% by mass, and still more preferably 0.1 to 5.0% by mass.

  Although it does not specifically limit as an organic solvent, For example, methanol, ethanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2 -Methyl-1-butanol, isopentyl alcohol, sec-butyl alcohol, tert-pentyl alcohol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 4-methyl- 2-pentanol, 2-ethyl-1-butanol, 1-heptanol, 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol, 1-methylcyclohexanol, 2 Alcohols such as methylcyclohexanol, 3-methylcyclohexanol, 4-methylcyclohexanol, 2-ethylhexyl alcohol, ketones such as acetone and MEK, esters such as methyl acetate and ethyl acetate, diethyl ether, dipropyl ether, Ethers such as tetrahydrofuran and dioxane, ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, trimethylene glycol, triethylene glycol, tetraethylene glycol, tetraethylene glycol and other glycols, ethylene glycol monomethyl Ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol Glycols such as nomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monobutyl ether Ethers, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, pro Examples include glycol esters such as pyrene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, and dipropylene glycol monobutyl ether acetate.

  A surfactant, a chelating agent, and the like may be appropriately added to the wafer cleaning composition of the present invention. In addition, other quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline and the like can be added.

(Wafer cleaning method)
By cleaning the silicon semiconductor substrate (silicon wafer) using this wafer cleaning composition, the silicon semiconductor substrate can be cleaned in a short time. Further, the wafer cleaning composition of the present invention is effective not only for cleaning a silicon substrate, but also particularly for cleaning a substrate having an adhesive (remaining) on a thinned substrate surface. It is. The adhesive referred to here is an adhesive that is used to fix the substrate to the support substrate when the substrate on which the semiconductor circuit is formed is thinned by back surface grinding. It remains on the substrate surface after peeling. Examples of the adhesive include synthetic organic adhesives such as silicone adhesives, acrylic adhesives, and olefin adhesives.

  The wafer cleaning method of the present invention can be cleaned by dipping, spraying, showering, ultrasonic cleaning, or the like using the above-described wafer cleaning composition, and for 30 seconds to 60 at an ambient temperature of about 10 to 70 ° C. The treatment can be performed in minutes, washed with water and dried. During the cleaning, it is possible to heat at a temperature below the boiling point of the wafer cleaning composition. The pH of the wafer cleaning composition is preferably adjusted to 9 to 14 before use.

  Hereinafter, although an example and a comparative example are shown and the present invention is explained in detail, the present invention is not limited to these.

[Example 1] (Synthesis of quaternary salt of formula (4))
Methyl DABCO (2-methyl-1,4diazabicyclo [2.2.2] octane) (64 g, 0.5 mol) and methyl iodide (127 g, 1.0 mol) were added to tetrahydrofuran (300 g), and the mixture was heated at room temperature (20 ° C.) for 1 hour. After stirring, stirring was continued at 50 ° C. for 1 hour. To the precipitated quaternary ammonium salt iodide, 500 g of ethanol was added, and 40 g (1.0 mol) of sodium hydroxide was slowly added. After removing the precipitated sodium iodide and adding water, ethanol was distilled off under reduced pressure to obtain 264 g of an aqueous solution containing a solid content dissolved at a ratio of 30% by mass.
The solid content in the obtained aqueous solution was taken out and subjected to infrared absorption spectrum analysis and 1H nuclear magnetic resonance spectrum analysis. As a result, it was confirmed that the compound had the structure of the following formula (4).

[Example 2] (Synthesis of quaternary salt of formula (4) and formula (5))
As a result of performing the same operation except that the amount of methyl iodide in Example 1 was 63.5 g (0.5 mol) and sodium hydroxide was 20 g (0.5 mol), the solid content was 30% by mass. 243 g of an aqueous solution containing dissolved at a ratio was obtained.
The solid content in the obtained aqueous solution was taken out and subjected to infrared absorption spectrum analysis and 1H nuclear magnetic resonance spectrum analysis. As a result, 25 mol% of the raw material methyl DABCO, 25 mol% of the compound having the structure of the above formula (4), and the following formula It was confirmed that this was a mixture of 50 mol% of the compound having the structure (5).

[Example 3] (Synthesis of quaternary salt of formula (6))
Instead of methyl DABCO (2-methyl-1,4 diazabicyclo [2.2.2] octane) in Example 1, 57 g (0.5 mol) of DABCO (1,4 diazabicyclo [2.2.2] octane) As a result of performing the same operation, 245 g of an aqueous solution containing a solid content dissolved at a ratio of 30% by mass was obtained.
The solid content in the obtained aqueous solution was taken out and subjected to infrared absorption spectrum analysis and 1H nuclear magnetic resonance spectrum analysis. As a result, it was confirmed that the compound had a structure of the following formula (6).

[Example 4] (Synthesis of quaternary salt of formula (7))
As a result of performing the same operation except that 156 g (1.0 mol) of ethyl iodide was used instead of methyl iodide in Example 3, 290 g of an aqueous solution containing a solid content dissolved at a ratio of 30% by mass was obtained. Obtained.
The solid content in the obtained aqueous solution was taken out and subjected to infrared absorption spectrum analysis and 1H nuclear magnetic resonance spectrum analysis. As a result, it was confirmed that the compound had a structure of the following formula (7).

[Example 5] (Synthesis of quaternary salt of formula (8))
As a result of performing the same operation except that the methyl iodide in Example 3 was changed to 137 g (1.0 mol) of n-butyl bromide and the reaction temperature was stirred at 80 ° C. for 5 hours, the solid content was reduced to 30. 380 g of an aqueous solution containing dissolved at a ratio of mass% was obtained.
The solid content in the obtained aqueous solution was taken out and subjected to infrared absorption spectrum analysis and 1H nuclear magnetic resonance spectrum analysis. As a result, it was confirmed that the compound had the structure of the following formula (8).

[Example 6]
A 500 ml flask equipped with a stirrer, a cooling device and a thermometer was charged with 3 g of an aqueous solution containing 30% by mass of the compound of the formula (4) synthesized in Example 1 and 97 g of 1-butoxy-2-propanol, and room temperature (20 The wafer cleaning composition A was obtained.

[Example 7]
A total of 25 mol% of the compound of the formula (4) synthesized in Example 2, 50 mol% of the compound of the formula (5) and 25 mol% of methyl DABCO as a raw material in a 500 ml flask equipped with a stirrer, a cooling device and a thermometer. 6 g of an aqueous solution containing 30% by mass of solid content, 44 g of ion-exchanged water, and 50 g of ethanol were charged and stirred at room temperature (20 ° C.) to obtain a wafer cleaning composition B.

[Example 8]
A 500 ml flask equipped with a stirrer, a cooling device and a thermometer was charged with 6 g of an aqueous solution containing 30% by mass of the compound of formula (6) synthesized in Example 3 and 94 g of ion-exchanged water, and stirred at room temperature (20 ° C.). A wafer cleaning composition C was obtained.

[Example 9]
Instead of the aqueous solution containing 30% by mass of the compound of the formula (4) in Example 6, 3 g of the aqueous solution containing 30% by mass of the compound of the formula (7) synthesized in Example 4 was used, and 1-butoxy-2-propanol Instead, 97 g of 1-propoxy 2-propanol was added and stirred at room temperature (20 ° C.) to obtain a wafer cleaning composition D.

[Example 10]
Instead of the aqueous solution containing 30% by mass of the compound of the formula (4) in Example 6, 10 g of an aqueous solution containing 30% by mass of the compound of the formula (8) synthesized in Example 5 was used instead of 1-butoxy-2-propanol. Was charged with 90 g of isopropanol, and stirred at room temperature (20 ° C.) to obtain a wafer cleaning composition E.

[Comparative Example 1]
A wafer cleaning composition F was obtained in the same manner except that 3 g of an aqueous solution containing 30% by mass of tetramethylammonium hydroxide was used instead of the aqueous solution containing 30% by mass of the compound of formula (4) in Example 6.

[Production of substrate]
Using a silicone resin / nonane solution adhesive, an adhesive layer having a thickness of 10 μm was formed by spin coating on an 8-inch silicon semiconductor substrate (diameter 200 mm, thickness: 725 μm). An 8-inch glass substrate (glass wafer) is used as a support substrate, and the support substrate and the silicon semiconductor substrate having the adhesive layer are bonded at 200 ° C. in a vacuum bonding apparatus, and includes the silicon semiconductor substrate, the adhesive layer, and the support substrate. A laminate was produced. Then, the back surface grinding of the silicon semiconductor substrate was performed using a grinder, and the final substrate thickness was ground to 50 μm. Subsequently, the silicon semiconductor substrate is fixed horizontally in the laminate, the support substrate is peeled off, then immersed in nonane as an organic solvent for 6 minutes, the adhesive layer is removed, and then dried, for a cleaning test. A silicon semiconductor substrate was produced. The water contact angle before the cleaning test of this cleaning test silicon semiconductor substrate was more than 60 degrees.

[Evaluation of substrate cleaning properties] (Table 1)
The silicon semiconductor substrate manufactured as described above was cleaned using the wafer cleaning compositions A to F. Specifically, the silicon semiconductor substrate is immersed in the wafer cleaning compositions A to F for 3 minutes or 5 minutes (that is, the cleaning time is 3 minutes or 5 minutes), rinsed with pure water for 1 minute, and dried. The water contact angle on the surface was confirmed with a fully automatic contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., model DM-701). As a result, regardless of which composition was used, the water contact angle of the silicon semiconductor substrate with a cleaning time of 5 minutes was less than 30 °, and the treated substrate surface was observed with a scanning electron microscope. It was confirmed that it was washed. Of these, corrosion of the silicon semiconductor substrate was observed for the wafer cleaning composition A of Example 6 and the wafer cleaning composition F of Comparative Example 1. Further, it was confirmed that the wafer cleaning compositions A and D (Examples 6 and 9) were cleaned cleanly even with a cleaning time of 3 minutes and there was no substrate corrosion (damage to the substrate). On the other hand, the wafer cleaning composition F of Comparative Example 1 was cleaned cleanly with a cleaning time of 3 minutes, but corrosion of the substrate was confirmed.

Claims (7)

A wafer cleaning composition comprising a quaternary ammonium hydroxide compound represented by the following formula (1) or formula (2) and water .

(In the formula, R ¹ is methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group or tert-butyl group , R ² , R ³ , R ⁴ , R ^5. , R ⁶ and R ⁷ are each a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 4 carbon atoms.) The wafer cleaning composition according to claim 1, wherein R ¹ is a methyl group or an ethyl group. The wafer cleaning composition according to claim 2, wherein R ¹ is an ethyl group. The wafer cleaning composition according to claim 1, wherein R ² is a hydrogen atom or a methyl group, and R ³ , R ⁴ , R ⁵ , R ⁶ , and R ⁷ are each a hydrogen atom. Furthermore, the composition for wafer cleaning of any one of Claims 1-4 containing an organic solvent. Wafer cleaning composition of any one of claims 1 to 5 concentration of the quaternary ammonium hydroxide compound is 0.1 to 10 mass%. A wafer cleaning method, comprising: cleaning a wafer to which an adhesive has adhered using the wafer cleaning composition according to any one of claims 1 to 6 .