WO2017159446A1

WO2017159446A1 - Liquid chemical for forming water-repellent protective film, and wafer washing method using said liquid chemical

Info

Publication number: WO2017159446A1
Application number: PCT/JP2017/008909
Authority: WO
Inventors: 由季福井; 崇齋尾; 両川　敦; 成塚　智; 彩織塩田; 翔太渡辺; 真太朗佐々木; 進岩崎
Original assignee: セントラル硝子株式会社
Priority date: 2016-03-15
Filing date: 2017-03-07
Publication date: 2017-09-21

Abstract

Provided is a liquid chemical for forming a water-repellent protective film, said liquid chemical being used in a wafer washing method that uses a washing device, said washing device including a vinyl chloride resin as a liquid-contacting member. A liquid chemical for forming a water-repellent protective film, said liquid chemical being for use in wafer washing using a washing device, said washing device including a vinyl chloride resin as a liquid-contacting member, said liquid chemical including: (I) an alkoxysilane expressed by general formula [1]; (II) a solvent that includes, at a ratio of 80-100mass%, at least one substance selected from the group consisting of hydrocarbons, ethers, and thiols; and (III) at least one substance selected from the group consisting of a sulfonic acid ester expressed by general formula [2], sulfonimides expressed by general formulas [3] and [4], sulfonimide derivatives expressed by general formulas [5] and [6], a sulfonmethide expressed by general formula [7], and a sulfonmethide derivative expressed by general formula [8].

Description

Chemical solution for forming water repellent protective film, and wafer cleaning method using the chemical solution

The present invention relates to a chemical solution for forming a water-repellent protective film for forming a water-repellent protective film on the surface of a wafer, and a wafer cleaning method using the chemical solution.

As described in Patent Documents 1 to 8, some wafer cleaning apparatuses use a vinyl chloride resin as a member that comes into contact with a cleaning solution or a processing solution (a liquid contact member). There is a need to not degrade the vinyl resin. As a cleaning apparatus containing a vinyl chloride resin as a liquid contact member, for example, a wafer cleaning apparatus or tank in which a part or all of the members that come into contact with the cleaning liquid or the processing liquid in the cleaning processing tank are made of vinyl chloride resin, a tank, Examples include a wafer cleaning apparatus in which a part or all of the members that come into contact with the cleaning liquid or processing liquid such as piping, connecting members, and nozzles are made of vinyl chloride resin.

In recent years, semiconductor devices for networks and digital home appliances are required to have higher performance, higher functionality, and lower power consumption. For this reason, miniaturization of the circuit pattern is progressing, and as the miniaturization progresses, pattern collapse of the circuit pattern becomes a problem. In semiconductor device manufacturing, a cleaning process for the purpose of removing particles and metal impurities is frequently used. As a result, the cleaning process accounts for 30 to 40% of the entire semiconductor manufacturing process. In this cleaning process, when the aspect ratio of the pattern increases with the miniaturization of the semiconductor device, the pattern collapses when the gas-liquid interface passes through the pattern after cleaning or rinsing. In order to prevent the occurrence of pattern collapse, the design of the pattern must be changed, or the yield during production may be reduced. Therefore, a method for preventing pattern collapse in the cleaning process is desired.

As a method for preventing pattern collapse, it is known that it is effective to form a water-repellent protective film on the pattern surface. Since this water repellency needs to be performed without drying the pattern surface, the water repellent protective film is formed with a water repellent protective film forming chemical that can make the pattern surface water repellent.

In the method of manufacturing a wafer having a fine concavo-convex pattern on the surface and at least a part of the concavo-convex pattern containing silicon element in Patent Document 9, the present applicant easily induces pattern collapse without impairing throughput. As a protective film-forming chemical for forming a water-repellent protective film on the surface of the concavo-convex pattern of the wafer for improving the cleaning process, a wafer having a fine concavo-convex pattern on the surface and at least a part of the concavo-convex pattern containing silicon element Is a chemical solution for forming a water-repellent protective film on at least the concave surface of the concavo-convex pattern, and the silicon compound A represented by the following general formula [A] and an acid that donates protons to the silicon compound A Or / and an acid that accepts electrons from the silicon compound A, and the total amount of moisture in the starting material of the chemical solution is 5 with respect to the total amount of the material Characterized in that 00 is mass ppm or less, and water-repellent protective film forming chemical, discloses a wafer cleaning method using the same.

[In the formula [A], R ^{1 s} each independently contain a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms and a fluoroalkyl chain having 1 to 8 carbon atoms. X is at least one group selected from a valent organic group, and X is independently of each other at least one selected from a halogen group, a monovalent organic group in which the element bonded to Si is oxygen or nitrogen, or a nitrile group A is an integer of 1 to 3, b is an integer of 0 to 2, and the sum of a and b is 3 or less. ]

JP 05-259136 A JP 07-245283 A Japanese Patent Laid-Open No. 10-189527 Japanese Patent Laid-Open No. 10-229062 JP 11-283949 A JP 2001-087725 A JP 2008-098440 A JP 2010-003739 A JP 2012-033873 A

In a method for cleaning a wafer having a fine concavo-convex pattern on the surface and at least a part of the concavo-convex pattern containing silicon element in a wafer cleaning apparatus containing a vinyl chloride resin as a liquid contact member, When the chemical solution for forming a water-repellent protective film described in Example 4 was used, the vinyl chloride resin might be deteriorated such as discoloration or swelling due to the chemical solution coming into contact with the liquid contact member.

Therefore, the present invention is a wafer cleaning apparatus including a vinyl chloride resin as a liquid contact member, and a wafer having a fine concavo-convex pattern on the surface and at least a part of the concavo-convex pattern including silicon element (hereinafter simply referred to as “wafer”). The water-repellent protective film (hereinafter sometimes simply referred to as “protective film”) formed on the surface of the concavo-convex pattern of the wafer has a large water-repellent improvement effect and is Provided is a water-repellent protective film-forming chemical solution (hereinafter, sometimes simply referred to as “protective film-forming chemical solution” or “chemical solution”), and a wafer cleaning method using the chemical solution, which have a great effect of preventing deterioration of the vinyl resin. This is the issue.

The present invention
(I) an alkoxysilane represented by the following general formula [1],
(II) a solvent containing at least one selected from the group consisting of hydrocarbons, ethers, and thiols in a proportion of 80 to 100% by mass, and (III) a sulfonate ester represented by the following general formula [2], Sulfonimides represented by the following general formulas [3] and [4], sulfonimide derivatives represented by the following general formulas [5] and [6], sulfonemethides represented by the following general formula [7], and the following general formulas A chemical solution for forming a water-repellent protective film for cleaning a wafer using a cleaning device containing a vinyl chloride resin as a liquid contact member, comprising at least one selected from the group consisting of sulfonemethide derivatives represented by formula [8].

[In the formula [1], each R ¹ is independently selected from monovalent hydrocarbon groups having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. At least one group, and R ² is each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, a is an integer of 1 to 3, b is an integer of 0 to 2, and the sum of a and b is 3 or less. ]

[In the formula [2], R ³ is selected from the group consisting of monovalent hydrocarbon groups having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and fluorine elements. R ⁴ is a monovalent alkyl group having 1 to 18 carbon atoms. ]

Wherein [3], R ⁵ are each independently of one another, a monovalent hydrocarbon group having some or all of the hydrogen element is carbon atoms, which may have been replaced by fluorine element 1-8 and, It is a group selected from the group consisting of fluorine elements. ]

[In the formula [4], R ⁶ is a divalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. ]

[In the formula [5], each R ⁷ is independently of each other a monovalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and R ⁸ is a group selected from the group consisting of fluorine elements, and R ⁸ is each independently a monovalent carbon atom having 1 to 18 carbon atoms, in which some or all of the hydrogen elements may be replaced by fluorine elements A hydrogen group, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c and d is 3 or less. ]

[In the formula [6], R ^{9 s} are each independently a divalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, R ^{10 s} are each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and e is 1 to 3 An integer, f is an integer from 0 to 2, and the sum of e and f is 3 or less. ]

[In the formula [7], R ¹¹ are each independently a monovalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and It is a group selected from the group consisting of fluorine elements. ]

[In the formula [8], R ¹² are each independently a monovalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and R ¹³ is a group selected from the group consisting of fluorine elements, and each R ¹³ , independently of each other, is a monovalent carbon atom having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements A hydrogen group, g is an integer of 1 to 3, h is an integer of 0 to 2, and the sum of g and h is 3 or less. ]

It is preferable that the (III) contains at least the sulfonimide derivative represented by the general formula [5] because a more excellent water repellency-imparting effect can be expressed. The (III) is represented by the general formula [5]. The sulfonimide derivative is particularly preferable because it can exhibit a further excellent water repellency imparting effect.

In the sulfonic acid ester, R ^{3 in the} general formula [2] is a group selected from the group consisting of a perfluoroalkyl group having 1 to 6 carbon atoms and a fluorine element, and R ⁴ is a group having 1 to 8 carbon atoms. The compound is preferably a monovalent alkyl group.

The sulfonimide is a compound in which R ^{5 in the} general formula [3] is a group selected from the group consisting of a perfluoroalkyl group having 1 to 6 carbon atoms and a fluorine element, and the general formula [4] R ⁶ is preferably a compound selected from the group consisting of compounds having a C ^1-6 perfluoroalkylene group.

The sulfonimide derivative is preferably a compound in which R ^{7 in the} general formula [5] is a group selected from the group consisting of a C 1-6 perfluoroalkyl group and a fluorine element.

The sulfonimide derivative is preferably a compound in which R ^{9 in the} general formula [6] is a perfluoroalkylene group having 1 to 6 carbon atoms.

The sulfonemethide is preferably a compound in which R ^{11 in the} general formula [7] is a group selected from the group consisting of a C 1-6 perfluoroalkyl group and a fluorine element.

The sulfonemethide derivative is preferably a compound in which R ^{12 in the} general formula [8] is a group selected from the group consisting of a perfluoroalkyl group having 1 to 6 carbon atoms and a fluorine element.

It is preferable that the hydrocarbon is a hydrocarbon having 6 to 13 carbon atoms.

The ether is preferably an ether represented by the following general formula [9].

[In the formula [9], R ¹⁴ and R ¹⁵ are each independently a monovalent carbon atom having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. It is a hydrogen group, and the total number of carbon atoms of R ¹⁴ and R ¹⁵ is 4 to 16. ]

The thiol is preferably a thiol having 6 to 13 carbon atoms.

The (I) is preferably at least one selected from the group consisting of alkoxysilanes represented by the following general formula [10].

[In the formula [10], R ¹⁶ are each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, R ¹⁷ Are each independently a monovalent hydrocarbon group having 1 to 12 carbon atoms, and i is 2 or 3. ]

The (I) is preferably at least one selected from the group consisting of monoalkoxysilanes represented by the following general formula [11].

[In the formula [11], R ¹⁸ is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and R ¹⁹ has 1 carbon atom. Is a monovalent hydrocarbon group of ˜12. ]

The concentration of (I) is preferably 0.5 to 35% by mass with respect to 100% by mass of the total amount of (I), (II), and (III).

The concentration of the total amount of the above (III) with respect to the total amount of 100% by mass of the above (I), (II), and (III) is preferably 0.0001 to 5% by mass.

The present invention is also a water repellent protective film-forming chemical solution kit for obtaining the water-repellent protective film-forming chemical solution according to any one of the above by mixing, at least including (I) above, or The above-mentioned (I) and at least one selected from the group consisting of hydrocarbons, ethers, and thiols, the first liquid, the above-mentioned (III), or the above-mentioned (III), and hydrocarbons, ethers And at least one selected from the group consisting of a hydrocarbon, an ether, and a thiol, wherein at least one of the first and second liquids includes at least one selected from the group consisting of thiols. A chemical solution kit for forming a water-repellent protective film containing seeds.

The present invention also relates to a method for cleaning a wafer using a cleaning device containing a vinyl chloride resin as a liquid contact member, and a water-repellent protective film is formed on the wafer surface by holding a chemical solution for forming the water-repellent protective film on the wafer surface. A water repellent protective film forming step, and the water repellent protective film forming chemical is
(I) an alkoxysilane represented by the following general formula [1],
(II) a solvent containing at least one selected from the group consisting of hydrocarbons, ethers, and thiols in a proportion of 80 to 100% by mass, and (III) a sulfonate ester represented by the following general formula [2], Sulfonimides represented by the following general formulas [3] and [4], sulfonimide derivatives represented by the following general formulas [5] and [6], sulfonemethides represented by the following general formula [7], and the following general formulas This is a method for cleaning a wafer containing at least one selected from the group consisting of sulfonemethide derivatives represented by the formula [8].

[In the formula [3], R ⁵ are each independently a monovalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and It is a group selected from the group consisting of fluorine elements. ]

The sulfonimide is, R ⁵ in the general formula [3] is a perfluoroalkyl group having 1 to 6 carbon atoms, and a compound which is a group selected from the group consisting of elemental fluorine, and the above general formula [4] R ⁶ is preferably a compound selected from the group consisting of compounds having a C ^1-6 perfluoroalkylene group.

The thiol is preferably a thiol having 6 to 13 carbon atoms.

After holding the water repellent protective film forming chemical in at least the recesses of the concave and convex pattern to form a water repellent protective film on the concave surface, the water repellent protective film forming chemical is removed from the recesses by drying. It is preferable.

The water-repellent protective film-forming chemical solution is held in at least the concave portion of the concavo-convex pattern, and after forming the water-repellent protective film on the concave surface, the water-repellent protective film-forming chemical solution in the concave portion is different from the chemical solution. It is preferable to replace with a cleaning liquid and remove the cleaning liquid from the recess by drying.

The water-repellent protective film may be removed by applying at least one treatment selected from the group consisting of heat treatment, light irradiation treatment, ozone exposure treatment, plasma irradiation treatment, and corona discharge treatment to the dried wafer surface. Good.

In addition, the cleaning method includes at least the first liquid containing (I) or including (I) and at least one selected from the group consisting of hydrocarbons, ethers, and thiols, Including the above (III) or the above (III) and a second liquid including at least one selected from the group consisting of hydrocarbons, ethers, and thiols. There is a step of obtaining the water repellent protective film forming chemical solution by mixing a water repellent protective film forming chemical solution kit containing at least one selected from the group consisting of hydrocarbons, ethers, and thiols. You may do it.

The chemical solution for forming a water-repellent protective film of the present invention has a great effect of improving the water repellency of the water-repellent protective film formed on the surface of the concavo-convex pattern of the wafer and has a great effect of preventing the deterioration of the vinyl chloride resin. Since the protective film formed by the chemical solution for forming a water-repellent protective film of the present invention is excellent in water repellency, it reduces the capillary force on the surface of the concavo-convex pattern of the wafer, and thus exhibits an effect of preventing pattern collapse. When the chemical solution is used, the cleaning step in the method for producing a wafer having a fine uneven pattern on the surface can be improved without lowering the throughput. Therefore, the method for producing a wafer having a fine concavo-convex pattern on the surface, which is performed using the chemical solution for forming a water repellent protective film of the present invention, has high productivity.

The aspect ratio of the circuit pattern on the wafer is expected to increase further with higher density. The chemical solution for forming a water-repellent protective film of the present invention can be applied to cleaning an uneven pattern having an aspect ratio of 7 or more, for example, and can reduce the production cost of a higher-density semiconductor device. In addition, the conventional apparatus can be applied without major changes such as a wetted member, and as a result, can be applied to the manufacture of various semiconductor devices.

It is a schematic diagram when the wafer 1 made into the surface which has the fine uneven | corrugated pattern 2 on the surface is seen. FIG. 2 shows a part of the a-a ′ cross section in FIG. 1. It is a schematic diagram of the state in which the recessed part 4 hold | maintained the chemical | medical solution 8 for protective film formation at the washing | cleaning process. It is a schematic diagram of the state by which the liquid was hold | maintained at the recessed part 4 in which the protective film was formed.

(1) About the water-repellent protective film-forming chemical solution The water-repellent protective film-forming chemical solution of the present invention is used for cleaning a wafer by a cleaning device containing a vinyl chloride resin as a liquid contact member,
(I) an alkoxysilane represented by the following general formula [1];
(II) a solvent containing at least one selected from the group consisting of hydrocarbons, ethers, and thiols in a proportion of 80 to 100% by mass;
(III) Sulfonic acid ester represented by the following general formula [2], sulfonimide represented by the following general formula [3] and [4], and sulfonimide represented by the following general formula [5] and [6] And at least one selected from the group consisting of a derivative, a sulfonemethide represented by the following general formula [7], and a sulfonemethide derivative represented by the following general formula [8].

Wherein [6], R ⁹ are each independently of one another, some or all of the hydrogen element is carbon atoms, which may have been replaced by fluorine element is a divalent hydrocarbon group of 1 to 8, R ^{10 s} are each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and e is 1 to 3 An integer, f is an integer from 0 to 2, and the sum of e and f is 3 or less. ]

About (I) component R < ¹ > of the alkoxysilane which is the said (I) component is a water-repellent functional group. Then, the alkoxysilane alkoxy groups (-OR ² group) reacts with the silanol groups on the wafer surface, by site having a functional group of the water-repellent is fixed to the wafer surface, the water repellent on the wafer surface A protective film is formed. When the alkoxysilane and the above (III) are used, the alkoxysilane and the wafer surface react quickly, and a water repellency imparting effect is obtained.

Specific examples of the _{_{alkoxysilane, CH 3 Si (OCH 3)}} 3, C 2 H 5 Si (OCH 3) 3, C 3 H 7 Si (OCH 3) 3, C 4 H 9 Si (OCH 3) 3 _{_{, C 5 H 11 Si (OCH}} 3) 3, C 6 H 13 Si (OCH 3) 3, C 7 H 15 Si (OCH 3) 3, C 8 H 17 Si (OCH 3) 3, C 9 H 19 Si (OCH ₃ ) ₃ , C ₁₀ H ₂₁ Si (OCH ₃ ) ₃ , C ₁₁ H ₂₃ Si (OCH ₃ ) ₃ , C ₁₂ H ₂₅ Si (OCH ₃ ) ₃ , C ₁₃ H ₂₇ Si (OCH ₃ ) ₃ , C ₁₄ H ₂₉ Si (OCH ₃ ) ₃ , C ₁₅ H ₃₁ Si (OCH ₃ ) ₃ , C ₁₆ H ₃₃ Si (OCH ₃ ) ₃ , C ₁₇ H ₃₅ Si (OCH ₃ ) ₃ , C ₁₈ H ₃₇ Si ( OCH ₃ ) ₃ , (CH ₃ ) ₂ Si (OCH ₃ ) ₂ , C ₂ H ₅ Si (CH ₃ ) (OCH ₃ ) ₂ , (C ₂ H ₅ ) ₂ Si (OCH ₃ ) ₂ , C ₃ H ₇ Si (CH ₃ ) (OCH ₃ ) ₂ , (C ₃ H ₇ ) ₂ Si (OCH ₃ ) ₂ , C ₄ H ₉ Si (CH ₃ ) (OCH ₃ ) ₂ , (C ₄ H ₉ ) ₂ Si (OCH _{_{_{_{3) 2, C 5 H 11}}}} Si (CH 3) (OCH 3) 2, C 6 H 13 Si (CH 3) (OCH 3) 2, C 7 H 15 Si (CH 3) (OCH 3) 2, C ₈ H ₁₇ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₉ H ₁₉ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₁₀ H ₂₁ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₁₁ H ₂₃ Si ( CH ₃ ) (OCH ₃ ) ₂ , C ₁₂ H ₂₅ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₁₃ H ₂₇ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₁₄ H ₂₉ Si (CH ₃ ) (OCH _{_{_{_{3) 2, C 15 H 31}}}} Si (CH 3) (OCH 3) 2, C 16 H 33 Si (CH 3) (OCH 3) 2, C 17 H 35 Si (CH 3) (OCH 3) 2, C ₁₈ H ₃₇ Si (CH ₃ _{_{(OCH 3) 2, (CH}} 3) 3 SiOCH 3, C 2 H 5 Si (CH 3) 2 OCH 3, (C 2 H 5) 2 Si (CH 3) OCH 3, (C 2 H 5) 3 SiOCH ₃ , C ₃ H ₇ Si (CH ₃ ) ₂ OCH ₃ , (C ₃ H ₇ ) ₂ Si (CH ₃ ) OCH ₃ , (C ₃ H ₇ ) ₃ SiOCH ₃ , C ₄ H ₉ Si (CH ₃ ) ₂ OCH ₃ , (C ₄ H ₉ ) ₃ SiOCH ₃ , C ₅ H ₁₁ Si (CH ₃ ) ₂ OCH ₃ , C ₆ H ₁₃ Si (CH ₃ ) ₂ OCH ₃ , C ₇ H ₁₅ Si (CH ₃ ) ₂ OCH ₃ , C ₈ H ₁₇ Si (CH ₃ ) ₂ OCH ₃ , C ₉ H ₁₉ Si (CH ₃ ) ₂ OCH ₃ , C ₁₀ H ₂₁ Si (CH ₃ ) ₂ OCH ₃ , C ₁₁ H ₂₃ Si (CH ₃ ) ₂ OCH ₃ , C ₁₂ H ₂₅ Si (CH ₃ ) ₂ OCH ₃ , C ₁₃ H ₂₇ Si (CH ₃ ) ₂ OCH ₃ , C ₁₄ H ₂₉ Si (CH ₃ ) ₂ OCH ₃ , C ₁₅ H ₃₁ S _{_{_{i (CH 3) 2 OCH 3}}} , C 16 H 33 Si (CH 3) 2 OCH 3, C 17 H 35 Si (CH 3) 2 OCH 3, C 18 H 37 Si (CH 3) 2 OCH 3, (CH ₃ ) ₂ Si (H) OCH ₃ , CH ₃ Si (H) ₂ OCH ₃ , (C ₂ H ₅ ) ₂ Si (H) OCH ₃ , C ₂ H ₅ Si (H) ₂ OCH ₃ , C ₂ H ₅ Si (CH ₃ ) (H) OCH ₃ , (C ₃ H ₇ ) ₂ Alkyl methoxysilane such as Si (H) OCH ₃ , or CF ₃ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₂ F ₅ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₃ F ₇ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₄ F ₉ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₅ F ₁₁ CH ₂ CH ₂ Si ( _{_{_{OCH 3) 3, C 6 F}}} 13 CH 2 CH 2 Si (OCH 3) 3, C 7 F 15 CH 2 CH 2 Si (OCH 3) 3, C 8 F 17 CH 2 CH 2 Si _{_{_{OCH 3) 3, CF 3 CH}}} 2 CH 2 Si (CH 3) (OCH 3) 2, C 2 F 5 CH 2 CH 2 Si (CH 3) (OCH 3) 2, C 3 F 7 CH 2 CH 2 Si (CH ₃ ) (OCH ₃ ) ₂ , C ₄ F ₉ CH ₂ CH ₂ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₅ F ₁₁ CH ₂ CH ₂ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₆ _{_{_{F 13 CH 2 CH 2 Si (}}} CH 3) (OCH 3) 2, C 7 F 15 CH 2 CH 2 Si (CH 3) (OCH 3) 2, C 8 F 17 CH 2 CH 2 Si (CH 3) ( _{_{_{OCH 3) 2, CF 3 CH}}} 2 CH 2 Si (CH 3) 2 OCH 3, C 2 F 5 CH 2 CH 2 Si (CH 3) 2 OCH 3, C 3 F 7 CH 2 CH 2 Si (CH 3) _{_{_{_{2 OCH 3, C 4 F 9}}}} CH 2 CH 2 Si (CH 3) 2 OCH 3, C 5 F 11 CH 2 CH 2 Si (CH 3) 2 OCH 3, C 6 F 13 CH 2 CH 2 _{_{_{i (CH 3) 2 OCH 3}}} , C 7 F 15 CH 2 CH 2 Si (CH 3) 2 OCH 3, C 8 F 17 CH 2 CH 2 Si (CH 3) 2 OCH 3, CF 3 CH 2 CH 2 Si Fluoroalkylmethoxysilane such as (CH ₃ ) (H) OCH ₃ , or the methyl group part of the methoxy group of the methoxysilane has a carbon number in which some or all of the hydrogen elements may be replaced with fluorine elements. Examples thereof include compounds substituted with 2 to 18 monovalent hydrocarbon groups.

Further, from the viewpoint of the effect of imparting water repellency, the number of carbon atoms of R ² of the alkoxy group (—OR ² group) is preferably 1 to 12, and the number of alkoxy groups (—OR ² group) is one, Or two is preferable. Further, from the viewpoint of easy maintenance of water repellency after forming the protective film, the number (b) of —H groups in the alkoxysilane represented by the general formula [1] is preferably zero. For this reason, the alkoxysilane is preferably at least one selected from the group consisting of alkoxysilanes represented by the following general formula [10].

Further, among the above specific examples, from the viewpoint of water repellency imparting effect, the alkoxysilane is preferably at least one selected from the group consisting of monoalkoxysilanes represented by the following general formula [11].

Specific examples of the monoalkoxysilane represented by the general formula [11] include (CH ₃ ) ₃ SiOCH ₃ , C ₂ H ₅ Si (CH ₃ ) ₂ OCH ₃ , and C ₃ H ₇ Si (CH ₃ ) _2. OCH ₃ , C ₄ H ₉ Si (CH ₃ ) ₂ OCH ₃ , C ₅ H ₁₁ Si (CH ₃ ) ₂ OCH ₃ , C ₆ H ₁₃ Si (CH ₃ ) ₂ OCH ₃ , C ₇ H ₁₅ Si (CH ₃ ) ₂ OCH ₃ , C ₈ H ₁₇ Si (CH ₃ ) ₂ OCH ₃ , CF ₃ CH ₂ CH ₂ Si (CH ₃ ) ₂ OCH ₃ , C ₂ F ₅ CH ₂ CH ₂ Si (CH ₃ ) ₂ OCH ₃ , _{_{_{_{C 3 F 7 CH 2 CH 2}}}} Si (CH 3) 2 OCH 3, C 4 F 9 CH 2 CH 2 Si (CH 3) 2 OCH 3, C 5 F 11 CH 2 CH 2 Si (CH 3) 2 OCH 3 alkyldimethyl monoalkoxysilane such as _{_{_{_{C 6 F 13 CH 2 CH 2}}}} Si (CH 3) 2 OCH 3 or, the Al Methyl moiety of a methoxy group Le dimethyl monoalkoxysilanes include compounds is replaced with monovalent hydrocarbon group having 2 to 12 carbon atoms and the like.

Further, from the viewpoint of water repellency imparting effect, R ¹⁸ is preferably a monovalent linear alkyl group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, Is preferably a monovalent unsubstituted linear alkyl group having 1 to 8 carbon atoms, particularly preferably a methyl group. In R ¹⁹ , the carbon atom bonded to the oxygen atom is preferably a primary carbon atom and an alkyl group having 1 to 8 carbon atoms.

Specific examples of particularly preferred monoalkoxysilanes include (CH ₃ ) ₃ SiOCH ₃ , (CH ₃ ) ₃ SiOC ₂ H ₅ , (CH ₃ ) ₃ SiOCH ₂ CH ₂ CH ₃ , (CH ₃ ) ₃ SiOCH ₂ CH _2. _{_{_{CH 2 CH 3, (CH 3}}} ) 3 SiOCH 2 CH (CH 3) 2, (CH 3) 3 SiOCH 2 CH 2 CH 2 CH 2 CH 3, (CH 3) 3 SiOCH 2 CH 2 CH (CH 3) 2 , (CH ₃ ) ₃ SiOCH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₃ , (CH ₃ ) ₃ SiOCH ₂ CH ₂ CH ₂ CH (CH ₃ ) ₂ , (CH ₃ ) ₃ SiOCH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₃ , (CH ₃ ) ₃ SiOCH ₂ CH ₂ CH ₂ CH ₂ CH (CH ₃ ) ₂ , (CH ₃ ) ₃ SiOCH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₃ , ( CH ₃ ) ₃ SiOCH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH (CH ₃ ) ₂ etc. are mentioned. Further, considering the solubility with the above (III), the number of carbon atoms of the alkoxy group of the monoalkoxysilane is preferably 3 to 8, and more preferably 4 to 8.

The concentration of the above (I) with respect to the total amount of 100% by mass of the above (I), (II) and (III) is preferably 0.5 to 35% by mass. If it is 0.5 mass% or more, it is preferable because the water repellency imparting effect is easily exhibited. Moreover, since it is hard to degrade a vinyl chloride resin if it is 35 mass% or less, it is preferable. The concentration is more preferably 0.7 to 30% by mass, and further preferably 1.0 to 25% by mass.

About (II) component The solvent which is said (II) component is a solvent for melt | dissolving said (I) and said (III). When the number of carbon atoms is small, the hydrocarbon has high volatility and low flash point, which is not preferable from the viewpoint of safety and liquid preparation workability. On the other hand, a large number of carbon atoms is not preferable from the viewpoint of ease of handling because the viscosity increases. Therefore, the hydrocarbon preferably has 6 to 13 carbon atoms.

Specific examples of the hydrocarbon include hexane, heptane, octane, nonane, decane, dodecane, tetradecane, hexadecane, octadecane, aicosane, cyclohexane, methylcyclohexane, decalin, benzene, toluene, xylene, diethylbenzene, and the like. From the viewpoint of viscosity, a saturated hydrocarbon having 8 to 12 carbon atoms is more preferable, and octane, nonane, decane, dodecane, and decalin are preferable.

Similarly, the ether is also preferably an ether represented by the following general formula [9], since a small number of carbon atoms is not preferable from the viewpoint of safety, and a large number of carbon atoms is not preferable from the viewpoint of easy handling. It is preferable.

Specific examples of the ether include dipropyl ether, ethyl butyl ether, dibutyl ether, ethyl amyl ether, diamyl ether, methyl cyclopentyl ether, ethyl hexyl ether, dihexyl ether, dioctyl ether, diphenyl ether, methyl perfluoropropyl ether, methyl perfluoro Examples include butyl ether, ethyl perfluorobutyl ether, methyl perfluorohexyl ether, and ethyl perfluorohexyl ether.

In particular, ethyl t-butyl ether and methylcyclopentyl ether are preferable because they are difficult to oxidize, and methyl perfluoropropyl ether, methyl perfluorobutyl ether, ethyl perfluorobutyl ether, methyl perfluorohexyl ether, and ethyl perfluorohexyl ether are nonflammable. Of these, dibutyl ether, diamyl ether, dihexyl ether, and dioctyl ether are preferred because of their excellent liquid preparation workability and high flash point.

The above thiol is obtained by replacing a hydrocarbon hydrogen atom with a mercapto group. The thiol is not preferable from the viewpoint of safety and environmental impact when the number of carbon atoms is small, and may deteriorate the vinyl chloride resin, and is not preferable from the viewpoint of ease of handling when the number of carbon atoms is large. Therefore, the thiol preferably has 6 to 13 carbon atoms. The thiol may have a plurality of mercapto groups, but preferably has one mercapto group.

Specific examples of the thiol include 1-hexanethiol, 2-hexanethiol, 3-hexanethiol, 2-methyl-1-pentanethiol, 3-methyl-1-pentanethiol, 4-methyl-1-pentanethiol, 2-methyl-2-pentanethiol, 3-methyl-2-pentanethiol, 4-methyl-2-pentanethiol, 2-methyl-3-pentanethiol, 3-methyl-3-pentanethiol, 2,2-dimethyl -1-butanethiol, 3,3-dimethyl-1-butanethiol, 3,3-dimethyl-2-butanethiol, 2-ethyl-1-butanethiol, 1-heptanethiol, 2-heptanethiol, 3-heptane Thiol, 4-heptanethiol, benzylthiol, 1-octanethiol, 2-octanethiol, -Octanethiol, 4-octanethiol, 2-ethyl-1-hexanethiol, 1-nonanethiol, 2-nonanethiol, 3-nonanethiol, 4-nonanethiol, 5-nonanethiol, 1-decanethiol, 2- Decanethiol, 3-decanethiol, 4-decanethiol, 5-decanethiol, tert-decanethiol, 1-undecanethiol, 2-undecanethiol, 3-undecanethiol, 4-undecanethiol, 5-undecanethiol, 6- Undecanethiol, 1-dodecanethiol, 2-dodecanethiol, 3-dodecanethiol, 4-dodecanethiol, 5-dodecanethiol, 6-dodecanethiol, tert-dodecanethiol, 1-tridecanethiol, 2-tridecanethiol, 3-tride Nchioru, 4-tridecane thiol, 5-tridecane thiol, 6-tridecane thiol, 7-tridecane thiol, and the like.

From the viewpoint of water repellency imparting effect, 1-hexanethiol, 2-methyl-1-pentanethiol, 3-methyl-1-pentanethiol, 4-methyl-1-pentanethiol, 2,2-dimethyl-1- Butanethiol, 3,3-dimethyl-1-butanethiol, 2-ethyl-1-butanethiol, 1-heptanethiol, benzylthiol, 1-octanethiol, 2-ethyl-1-hexanethiol, 1-nonanethiol, Primary thiols such as 1-decanethiol, 1-undecanethiol, 1-dodecanethiol and 1-tridecanethiol are preferred.

The chemical solution of the present invention may contain an organic solvent other than at least one solvent selected from the group consisting of hydrocarbons, ethers, and thiols, but the viewpoint of preventing the deterioration of the vinyl chloride resin, And / or from a viewpoint of the water-repellent provision effect, another organic solvent is less than 20 mass% with respect to 100 mass% of solvent total amount. From the viewpoint of achieving a well-balanced effect of preventing the deterioration of the vinyl chloride resin and imparting water repellency, it is preferably less than 10% by mass, and more preferably less than 5% by mass. That is, at least one solvent selected from the group consisting of hydrocarbons, ethers, and thiols is 80 to 100% by mass, preferably 90 to 100% by mass, with respect to 100% by mass of the total amount of solvent. More preferably, it is ˜100 mass%.

Examples of organic solvents other than at least one solvent selected from the group consisting of hydrocarbons, ethers, and thiols include, for example, esters, ketones, halogen-containing solvents, sulfoxide solvents, lactone solvents, carbonate solvents, Examples include alcohols, polyhydric alcohol derivatives, and silicone solvents. In particular, alcohols and derivatives of polyhydric alcohols having an OH group are preferable from the viewpoint of improving the solubility of the component (III), and do not have esters, ketones, halogen-containing solvents, and OH groups. A derivative of a polyhydric alcohol is preferable from the viewpoint of water repellency imparting effect.

(III) Component (III) The component (III) promotes the reaction between the alkoxy group (—OR ² group) of the above (I) and the silanol group on the wafer surface, and itself forms a part of the protective film. You may do.

Specific examples of the sulfonate ester include methyl methanesulfonate, methyl benzenesulfonate, methyl paratoluenesulfonate, methyl trifluoromethanesulfonate, methyl pentafluoroethanesulfonate, methyl heptafluoropropanesulfonate, and nonafluorobutanesulfone. Examples thereof include methyl sulfonates such as methyl acrylate and methyl tridecafluorohexane sulfonate, or compounds in which the methyl group portion of the methyl sulfonate is replaced with an ethyl group, a propyl group, a butyl group, or an octyl group.

Further, from the viewpoint of promoting the above reaction (and in view of the effect of imparting water repellency), it is preferable that the R ³ group of the general formula [2] is a perfluoroalkyl group. A perfluoroalkyl group having a number of 6 or less is preferable, and is a perfluoroalkyl group such as methyl trifluoromethanesulfonate, methyl pentafluoroethanesulfonate, methyl heptafluoropropanesulfonate, methyl nonafluorobutanesulfonate, or methyl tridecafluorohexanesulfonate. Preference is given to methyl fluoroalkylsulfonate or a compound in which the methyl group part of the methyl perfluoroalkylsulfonate is replaced with an ethyl group, a propyl group, a butyl group or an octyl group.

Specific examples of the sulfonimide include bis (methanesulfonyl) imide, bis (fluorosulfonyl) imide, bis (trifluoromethanesulfonyl) imide, bis (pentafluoroethanesulfonyl) imide, bis (heptafluoropropanesulfonyl) imide, bis (Nonafluorobutanesulfonyl) imide, bis (tridecafluorohexanesulfonyl) imide, N, N-hexafluoropropane-1,3-bis (sulfonyl) imide, N, N-octafluorobutane-1,3-bis ( Sulfonyl) imide, N, N-decafluoropentane-1,3-bis (sulfonyl) imide, N, N-dodecafluorohexane-1,3-bis (sulfonyl) imide and the like.

Further, from the viewpoint of promoting the reaction (and in view of the effect of imparting water repellency), the R ⁵ group of the general formula [3] is a group selected from the group consisting of a perfluoroalkyl group and a fluorine element. In addition, the R ⁶ group of the general formula [4] is preferably a perfluoroalkylene group. Further, a perfluoroalkyl group R ⁵ groups of 6 or less carbon atoms in the above general formula [3] in terms of environmental impact, and, more preferably a group selected from the group consisting of elemental fluorine, Moreover, it is more preferable that the R ⁶ group of the general formula [4] is a perfluoroalkylene group having 6 or less carbon atoms.

Specifically, bis (fluorosulfonyl) imide, bis (trifluoromethanesulfonyl) imide, bis (pentafluoroethanesulfonyl) imide, bis (heptafluoropropanesulfonyl) imide, bis (nonafluorobutanesulfonyl) imide, bis (tri Perfluoroalkylsulfonimide such as decafluorohexanesulfonyl) imide, N, N-hexafluoropropane-1,3-bis (sulfonyl) imide, N, N-octafluorobutane-1,3-bis (sulfonyl) imide, N, N-decafluoropentane-1,3-bis (sulfonyl) imide and N, N-dodecafluorohexane-1,3-bis (sulfonyl) imide are preferred.

Specific examples of the sulfonimide derivative include N- (trimethylsilyl) bis (methanesulfonyl) imide, N- (dimethylsilyl) bis (methanesulfonyl) imide, N- (ethyldimethylsilyl) bis (methanesulfonyl) imide, N -(Propyldimethylsilyl) bis (methanesulfonyl) imide, N- (tripropylsilyl) bis (methanesulfonyl) imide, N- (butyldimethylsilyl) bis (methanesulfonyl) imide, N- (octyldimethylsilyl) bis ( N- (alkylsilyl) bis (methanesulfonyl) imide such as methanesulfonyl) imide or the methanesulfonyl group portion of the N- (alkylsilyl) bis (methanesulfonyl) imide is substituted with ethanesulfonyl group, propanesulfonyl group, octane Sulfonyl group, fluorosulfonyl group, trifluoro A compound substituted with a methanesulfonyl group, a pentafluoroethanesulfonyl group, a heptafluoropropanesulfonyl group, a nonafluorobutanesulfonyl group, a tridecafluorohexanesulfonyl group, and the like of the N- (alkylsilyl) bis (methanesulfonyl) imide The bis (methanesulfonyl) imide moiety is substituted with N, N-methane-1,3-bis (sulfonyl) imide, N, N-ethane-1,3-bis (sulfonyl) imide, N, N-propane-1,3 -Bis (sulfonyl) imide, N, N-butane-1,3-bis (sulfonyl) imide, N, N-pentane-1,3-bis (sulfonyl) imide, N, N-hexane-1,3-bis (Sulfonyl) imide, N, N-heptane-1,3-bis (sulfonyl) imide, N, N-octane-1,3-bis ( (Sulfonyl) imide, N, N-difluoromethane-1,3-bis (sulfonyl) imide, N, N-tetrafluoroethane-1,3-bis (sulfonyl) imide, N, N-hexafluoropropane-1,3 -Bis (sulfonyl) imide, N, N-octafluorobutane-1,3-bis (sulfonyl) imide, N, N-decafluoropentane-1,3-bis (sulfonyl) imide, N, N-dodecafluorohexane -1,3-bis (sulfonyl) imide, N, N-tetradecafluoroheptane-1,3-bis (sulfonyl) imide, N, N-hexadecafluorooctane-1,3-bis (sulfonyl) imide And the like.

It is preferable that the (III) contains at least the sulfonimide derivative represented by the general formula [5] because a more excellent water repellency-imparting effect can be expressed. The (III) is represented by the general formula [5]. The sulfonimide derivative is particularly preferable because it can exhibit a further excellent water repellency imparting effect. From the viewpoint of promoting the above reaction (and in view of the effect of imparting water repellency), the R ⁷ group of the general formula [5] is preferably a group selected from the group consisting of a perfluoroalkyl group and a fluorine element. Further, from the viewpoint of influence on the environment, the R ⁷ group of the general formula [5] is more preferably a group selected from the group consisting of a perfluoroalkyl group having 6 or less carbon atoms and a fluorine element.

In addition, from the viewpoint of promoting the above reaction (and hence from the viewpoint of imparting water repellency), the R ⁹ group of the general formula [6] is preferably a perfluoroalkylene group, and further from the viewpoint of influence on the environment. more preferably R ⁹ groups of formula [6] is a perfluoroalkylene group having six or less carbon atoms.

Specifically, the methanesulfonyl group portion of the N- (alkylsilyl) bis (methanesulfonyl) imide is a fluorosulfonyl group, trifluoromethanesulfonyl group, pentaoloethanesulfonyl group, heptafluoropropanesulfonyl group, nonafluorobutanesulfonyl group. Group, a tridecafluorohexanesulfonyl group and the like, and the bis (methanesulfonyl) imide moiety of the N- (alkylsilyl) bis (methanesulfonyl) imide are substituted with N, N-difluoromethane-1,3- Bis (sulfonyl) imide, N, N-tetrafluoroethane-1,3-bis (sulfonyl) imide, N, N-hexafluoropropane-1,3-bis (sulfonyl) imide, N, N-octafluorobutane- 1,3-bis (sulfonyl) imide, N, N-deca Ruoropentan-1,3-bis (sulfonyl) imide, N, N-dodecafluoro hexane-1,3-bis (sulfonyl) compound is replaced with the imide and the like are preferable.

Specific examples of the sulfonemethide include tris (methanesulfonyl) methide, tris (trifluoromethanesulfonyl) methide, tris (pentafluoroethanesulfonyl) methide, tris (heptafluoropropanesulfonyl) methide, tris (nonafluorobutanesulfonyl) methide, And tris (tridecafluorohexanesulfonyl) methide.

In addition, from the viewpoint of promoting the above reaction (and in view of the effect of imparting water repellency), it is preferable that the R ¹¹ group of the general formula [7] is a perfluoroalkyl group, and further from the viewpoint of influence on the environment, carbon. A perfluoroalkyl group having a number of 6 or less is preferable, and tris (trifluoromethanesulfonyl) methide, tris (pentafluoroethanesulfonyl) methide, tris (heptafluoropropanesulfonyl) methide, tris (nonafluorobutanesulfonyl) methide, tris ( Perfluoroalkylsulfone methides such as tridecafluorohexanesulfonyl) methide are preferred.

Specific examples of the sulfonemethide derivatives include (trimethylsilyl) tris (methanesulfonyl) methide, (dimethylsilyl) tris (methanesulfonyl) methide, (ethyldimethylsilyl) tris (methanesulfonyl) methide, (propyldimethylsilyl) tris (methane (Alkylsilyl) tris (methanesulfonyl) such as (sulfonyl) methide, (tripropylsilyl) tris (methanesulfonyl) methide, (butyldimethylsilyl) tris (methanesulfonyl) methide, (octyldimethylsilyl) tris (methanesulfonyl) methide Methide or the methanesulfonyl group of the above (alkylsilyl) tris (methanesulfonyl) methide is substituted with ethanesulfonyl group, propanesulfonyl group, octanesulfonyl group, trifluoromethanesulfonyl group, pentafluoroethane. Sulfonyl group, heptafluoropropanesulfonyl group, nonafluorobutanesulfonyl group, the compound was replaced by tridecafluoro hexanesulfonyl group and the like.

In addition, from the viewpoint of promoting the above reaction (and in view of the effect of imparting water repellency), it is preferable that the R ¹² group of the general formula [8] is a perfluoroalkyl group. A perfluoroalkyl group having 6 or less is preferable, and the methanesulfonyl group portion of the (alkylsilyl) tris (methanesulfonyl) methide is substituted with a trifluoromethanesulfonyl group, a pentafluoroethanesulfonyl group, a heptafluoropropanesulfonyl group, a nonafluoro group. A compound substituted with a butanesulfonyl group, a tridecafluorohexanesulfonyl group or the like is preferable.

The concentration of the total amount of (III) with respect to the total amount of 100% by mass of (I), (II), and (III) is preferably 0.0001 to 5% by mass. If it is 0.0001 mass% or more, the reaction promoting effect (and consequently the water repellency imparting effect) is easily exhibited, which is preferable. If it is 5% by mass or less, it is difficult to erode the wafer surface and the like, and it is difficult to remain on the wafer as an impurity. In addition, it is preferable that a non-homogeneous chemical solution does not occur without being dissolved in the solvent because it hardly occurs. The concentration is more preferably from 0.01 to 2% by mass, even more preferably from 0.05 to 1% by mass.

The chemical solution of the present invention may contain additives such as a polymerization inhibitor, a chain transfer agent, and an antioxidant in order to further improve the stability of the chemical solution. For example, 4-methoxyphenol, dibutylhydroxytoluene, butylhydroxyanisole, 1,4-benzenediol, 2- (1,1-dimethylethyl) -1,4-benzenediol, 1,4-benzoquinone, 1-octanethiol 1-nonanethiol, 1-decanethiol, 1-undecanethiol, 1-dodecanethiol, octyl-3,5-di-tert-butyl-4-hydroxy-hydrocarbinic acid (manufactured by BASF, Irganox 1135), 6-tert -Butyl-2,4-xylenol and the like.

In addition, from the viewpoint of the cleanliness of the chemical solution, the above additive is preferably a liquid. For example, 1-dodecanethiol, octyl-3,5-di-tert-butyl-4-hydroxy-hydrocarbine which is liquid at 25 ° C. and atmospheric pressure. Acids (manufactured by BASF, Irganox 1135), 6-tert-butyl-2,4-xylenol and the like are preferable.

In addition, the total amount of moisture in the starting material of the chemical solution is preferably 2000 ppm by mass or less with respect to the total amount of the material. When the total amount of moisture exceeds 2000 ppm by mass, the effects (I) and (III) are reduced, and it is difficult to form the protective film in a short time. For this reason, it is preferable that the total amount of water in the chemical solution raw material is as small as possible, particularly 500 mass ppm or less, and more preferably 200 mass ppm or less. Furthermore, since the storage stability of the said chemical | medical solution will fall easily when there are many amounts of water, the one where water content is small is preferable, 100 mass ppm or less, Furthermore, 50 mass ppm or less is preferable. In addition, although the said moisture content is so preferable that it is small, as long as it exists in said content range, 0.1 mass ppm or more may be sufficient as the moisture content in the said chemical | medical solution raw material. Therefore, it is preferable that (I), (II), and (III) contained in the said chemical | medical solution do not contain much water.

Further, it is preferable that the number of particles larger than 0.2 μm in the liquid measurement in the liquid phase in the chemical solution is 100 or less per 1 mL of the chemical solution. If the number of particles larger than 0.2 μm is more than 100 per 1 mL of the chemical solution, pattern damage due to the particles may be induced, which causes a decrease in device yield and reliability. Further, it is preferable that the number of particles larger than 0.2 μm is 100 or less per mL of the chemical solution because washing with a solvent or water after forming the protective film can be omitted or reduced. The number of particles larger than 0.2 μm is preferably as small as possible, but may be 1 or more per 1 mL of the chemical solution as long as it is within the above content range.

The particle measurement in the liquid phase in the chemical solution in the present invention is performed by using a commercially available measuring device in the light scattering liquid particle measurement method using a laser as a light source. , PSL (polystyrene latex) standard particle-based light scattering equivalent diameter.

Here, the particles are particles such as dust, dust, organic solids and inorganic solids contained as impurities in the raw materials, and dust, dust, organic solids and inorganic solids brought in as contaminants during the preparation of chemicals. It is a particle such as an object, and finally exists as a particle without being dissolved in a chemical solution.

In addition, the content of each element (metal impurity) of Na, Mg, K, Ca, Mn, Fe, Cu, Li, Al, Cr, Ni, Zn, and Ag in the chemical solution is 0 for each total amount of the chemical solution. .1 mass ppb or less is preferable. If the metal impurity content is more than 0.1 mass ppb with respect to the total amount of the chemical solution, it is likely to increase the junction leakage current of the device, which causes a decrease in device yield and reliability. Absent. Further, when the metal impurity content is 0.1 mass ppb or less with respect to the total amount of the chemical solution, the surface of the wafer (protective film surface) with the solvent or water after the protective film is formed on the wafer surface. This is preferable because cleaning can be omitted or reduced. For this reason, the content of the metal impurities is preferably as small as possible, but may be 0.001 mass ppb or more for each element with respect to the total amount of the chemical solution as long as it is within the above content range.

Further, the chemical solution of the present invention may be obtained by mixing a water-repellent protective film-forming chemical solution kit containing the first liquid and the second liquid described above.

(2) Water-repellent protective film In the present invention, the water-repellent protective film is a film that reduces the wettability of the wafer surface by being formed on the wafer surface, that is, a film that imparts water repellency. . In the present invention, the water repellency means that the surface energy of the article surface is reduced and the interaction (for example, hydrogen bond, intermolecular force) between water or other liquid and the article surface is reduced. It is. In particular, the effect of reducing the interaction with water is great, but it has the effect of reducing the interaction with a mixed liquid of water and a liquid other than water or a liquid other than water. By reducing the interaction, the contact angle of the liquid with the article surface can be increased. In addition, the water repellent protective film may be formed from the above (I) or may contain a reactant having (I) as a main component.

(3) Wafer As the above wafer, the wafer surface is formed with a film containing a silicon element such as silicon, silicon oxide, or silicon nitride, or the surface of the concavo-convex pattern when the concavo-convex pattern is formed. In which at least a part of silicon contains silicon element such as silicon, silicon oxide, or silicon nitride. In addition, a protective film can be formed on the surface of a component containing a silicon element even for a wafer composed of a plurality of components containing at least a silicon element. As the wafer composed of the plurality of components, silicon, silicon oxide, silicon nitride and other components containing silicon elements are formed on the wafer surface, or when the concavo-convex pattern is formed, at least the concavo-convex pattern A part of which includes a silicon element such as silicon, silicon oxide, and silicon nitride is also included. In addition, it is the surface of the part containing the silicon element in the said uneven | corrugated pattern that can form a protective film with the said chemical | medical solution.

In general, in order to obtain a wafer having a fine concavo-convex pattern on the surface, first, after applying a resist to a smooth wafer surface, the resist is exposed through a resist mask, and the exposed resist or exposed A resist having a desired concavo-convex pattern is produced by etching away the resist that was not present. Moreover, the resist which has an uneven | corrugated pattern can be obtained also by pressing the mold which has a pattern to a resist. Next, the wafer is etched. At this time, the wafer surface corresponding to the concave portion of the resist pattern is selectively etched. Finally, when the resist is removed, a wafer having a fine uneven pattern is obtained.

After the surface of the wafer has a fine uneven pattern, the surface is cleaned with an aqueous cleaning solution, and the aqueous cleaning solution is removed by drying or the like. When the width of the concave portion is small and the aspect ratio of the convex portion is large, the pattern collapses. Is likely to occur. The concavo-convex pattern is defined as shown in FIGS. FIG. 1 is a schematic view when a wafer 1 whose surface has a fine concavo-convex pattern 2 is viewed from the perspective, and FIG. 2 shows a part of the aa ′ cross section in FIG. . As shown in FIG. 2, the width 5 of the concave portion is shown by the interval between the convex portions 3 adjacent to each other, and the aspect ratio of the convex portion is obtained by dividing the height 6 of the convex portion by the width 7 of the convex portion. It is represented by Pattern collapse in the cleaning process tends to occur when the width of the recess is 70 nm or less, particularly 45 nm or less, and the aspect ratio is 4 or more, particularly 6 or more.

(4) Wafer Cleaning Method The cleaning method of the present invention is a method of cleaning a wafer having a fine uneven pattern on the surface obtained by etching as described above. It includes a protective film forming step of forming a water repellent protective film on the wafer surface by holding it on the wafer surface.

Prior to the cleaning method of the present invention, the wafer may be cleaned with an aqueous cleaning solution in order to remove etching residues, etc., and the aqueous cleaning solution held in the recess after the cleaning may be different from the cleaning solution different from the aqueous cleaning solution. (Hereinafter referred to as “cleaning liquid A”) may be substituted and further washed.

Examples of the aqueous cleaning liquid include water or an aqueous solution in which at least one of organic solvents, hydrogen peroxide, ozone, acid, alkali, and surfactant is mixed in water (for example, the water content is 10 mass). % Or more).

The cleaning liquid A refers to an organic solvent, a mixture of the organic solvent and an aqueous cleaning liquid, and a cleaning liquid in which at least one of acid, alkali, and surfactant is mixed.

In the present invention, the cleaning method of the wafer is not particularly limited as long as the cleaning device capable of holding the chemical solution or the cleaning solution is used in at least the concave portion of the concave / convex pattern of the wafer. As a wafer cleaning method, a single wafer method typified by a cleaning method using a spin cleaning apparatus that cleans wafers one by one by supplying a liquid near the rotation center while rotating the wafer while holding the wafer substantially horizontal, A batch method using a cleaning apparatus that immerses and cleans a plurality of wafers in a cleaning tank may be used. The form of the chemical solution or the cleaning liquid when supplying the chemical solution or the cleaning liquid to at least the concave portion of the concave / convex pattern of the wafer is not particularly limited as long as it becomes liquid when held in the concave portion. And steam.

Examples of the organic solvent that is one of the preferred examples of the cleaning liquid A include hydrocarbons, esters, ethers, ketones, halogen-containing solvents, sulfoxide solvents, lactone solvents, carbonate solvents, alcohols, Examples include polyhydric alcohol derivatives, nitrogen element-containing solvents, and the like. Of these, hydrocarbons, ethers, alcohols, and polyhydric alcohol derivatives having no OH group and acetate group are preferable because the vinyl chloride resin is hardly deteriorated. When an organic solvent is used as the cleaning liquid A, hydrocarbons, ethers, alcohols, polyhydric alcohol derivatives having no OH group and acetate group, which are preferable solvents, are 80% by mass of the total amount of the organic solvent. It is desirable to occupy the above.

In the protective film forming step, the chemical liquid for forming a protective film of the present invention is used by replacing the aqueous cleaning liquid or cleaning liquid A with the chemical liquid. In addition, the replaced chemical liquid may be replaced with a cleaning liquid different from the chemical liquid (hereinafter referred to as “cleaning liquid B”).

In addition, the wafer cleaning method of the present invention includes mixing a water repellent protective film forming chemical solution kit including the first liquid and the second liquid, as described above, prior to the replacement of the aqueous cleaning liquid or the cleaning liquid A with the chemical liquid. By doing so, you may have the process of obtaining the said chemical | medical solution.

After the cleaning with the aqueous cleaning liquid or the cleaning liquid A as described above, the cleaning liquid is replaced with a protective film-forming chemical solution, and at least the surface of the concave and convex pattern has at least the surface of the concave and convex pattern while the chemical liquid is held in at least the concave portion Then, the protective film is formed. The protective film of the present invention does not necessarily have to be formed continuously, and does not necessarily have to be formed uniformly. However, since it can impart better water repellency, it can be applied continuously and uniformly. More preferably, it is formed.

FIG. 3 shows a schematic view of the state in which the recess 4 holds the protective film forming chemical 8. The wafer shown in the schematic diagram of FIG. 3 shows a part of the a-a ′ cross section of FIG. 1. At this time, a protective film is formed on the surface of the recess 4 to make the surface water repellent.

When the temperature of the chemical for forming a protective film is increased, the protective film is easily formed in a shorter time. The temperature at which a homogeneous protective film is easily formed is preferably 10 ° C. or higher and lower than the boiling point of the chemical solution, and particularly preferably 15 ° C. or higher and 10 ° C. lower than the boiling point of the chemical solution. The temperature of the chemical solution is preferably maintained at the temperature even when held in at least the concave portion of the concavo-convex pattern. The boiling point of the chemical solution means the boiling point of the component having the largest amount by mass ratio among the components contained in the protective film forming chemical solution.

The chemical solution for forming a protective film according to the present invention includes, for example, a wafer cleaning device, tank, pipe, connecting member, nozzle, and the like, in which a part or all of the members in contact with the chemical solution in the cleaning treatment tank are made of vinyl chloride resin. In application to a wafer cleaning apparatus in which some or all of the members that come into contact with the chemical solution are made of vinyl chloride resin, the effect of preventing the deterioration of the vinyl chloride resin is great. In addition, “a member whose vinyl chloride resin is partly” includes a member whose member is a vinyl chloride resin, a member whose surface is covered with a vinyl chloride resin, and the like.

After forming the protective film as described above, the chemical solution remaining in at least the concave portion of the concave / convex pattern may be replaced with the cleaning liquid B, and then the drying process may be performed. Examples of the cleaning liquid B include an aqueous cleaning liquid, an organic solvent, a mixture of an aqueous cleaning liquid and an organic solvent, a mixture of at least one of an acid, an alkali, and a surfactant, and a protective film with them. Examples include a mixture of chemicals for forming. The cleaning liquid B is more preferably water, an organic solvent, or a mixture of water and an organic solvent from the viewpoint of removing particles and metal impurities.

Examples of the organic solvent that is one of the preferred examples of the cleaning liquid B include hydrocarbons, esters, ethers, ketones, halogen-containing solvents, sulfoxide solvents, alcohols, polyhydric alcohol derivatives, nitrogen elements Examples thereof include a solvent. Of these, hydrocarbons, ethers, alcohols, and polyhydric alcohol derivatives having no OH group and acetate group are preferable because the vinyl chloride resin is hardly deteriorated. When an organic solvent is used as the cleaning liquid B, hydrocarbons, ethers, alcohols, polyhydric alcohol derivatives having no OH group and acetate group, which are preferable solvents, are 80% by mass of the total amount of the organic solvent. It is desirable to occupy the above.

In addition, when an organic solvent is used as the cleaning liquid B, the protective film formed on the wafer surface with the chemical liquid of the present invention may not easily be reduced in water repellency due to the cleaning of the cleaning liquid B.

FIG. 4 shows a schematic diagram when the liquid is held in the recess 4 made water repellent by the protective film forming chemical. The wafer in the schematic diagram of FIG. 4 shows a part of the a-a ′ cross section of FIG. The surface of the concavo-convex pattern is made water-repellent by forming a protective film 10 with the chemical solution. The protective film 10 is held on the wafer surface even when the liquid 9 is removed from the concavo-convex pattern.

When the protective film 10 is formed on at least the concave surface of the concave / convex pattern of the wafer with the chemical solution for forming the protective film, the pattern collapses when the contact angle is 50 to 130 ° on the assumption that water is held on the surface. Is preferable because it is difficult to occur. When the contact angle is large, the water repellency is excellent, so 60 to 130 ° is more preferable, and 65 to 130 ° is particularly preferable. In addition, the amount of decrease in the contact angle before and after cleaning with the cleaning liquid B (contact angle before cleaning the cleaning liquid B−contact angle after cleaning the cleaning liquid B) is preferably 10 ° or less.

Next, the liquid held in the recess 4 in which the protective film is formed by the chemical solution is removed from the uneven pattern by drying. At this time, the liquid held in the recess may be the chemical solution, the cleaning solution B, or a mixed solution thereof. The mixed liquid is contained so that each component contained in the protective film forming chemical solution is at a lower concentration than the chemical liquid, and the mixed liquid is in a state of being replaced with the cleaning liquid B. The liquid may be sufficient, and the liquid mixture obtained by mixing each said component with the washing | cleaning liquid B previously may be sufficient. From the viewpoint of the cleanliness of the wafer, water, an organic solvent, or a mixture of water and an organic solvent is preferable. Moreover, after the liquid is once removed from the surface of the concave / convex pattern, the cleaning liquid B may be held on the surface of the concave / convex pattern and then dried.

In the case of cleaning with the cleaning liquid B after the formation of the protective film, the cleaning time, that is, the time for which the cleaning liquid B is held is 10 seconds or more, more preferably 20 from the viewpoint of removing particles and impurities on the uneven pattern surface. It is preferable to carry out for 2 seconds or more. From the viewpoint of the effect of maintaining the water repellency of the protective film formed on the surface of the uneven pattern, when an organic solvent is used as the cleaning liquid B, the water repellency of the wafer surface tends to be easily maintained even after the cleaning. On the other hand, if the washing time is too long, productivity is deteriorated.

The liquid held in the uneven pattern is removed by the above drying. The drying is preferably performed by a known drying method such as a spin drying method, IPA (2-propanol) vapor drying, Marangoni drying, heat drying, hot air drying, air drying, or vacuum drying.

The protective film 10 may be further removed after the drying. When removing the water repellent protective film, it is effective to cut the C—C bond and C—F bond in the water repellent protective film. The method is not particularly limited as long as it can cut the bond, for example, light irradiation of the wafer surface, heating of the wafer, exposure of the wafer to ozone, irradiation of the wafer surface with plasma, For example, corona discharge on the wafer surface may be mentioned.

When removing the protective film 10 by light irradiation, shorter than 340 nm and 240 nm, which are energy equivalent to 83 kcal / mol and 116 kcal / mol, which are binding energy of CC bond and CF bond in the protective film 10 It is preferable to irradiate ultraviolet rays including wavelengths. As this light source, a metal halide lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an excimer lamp, a carbon arc, or the like is used. If the ultraviolet irradiation intensity is a metal halide lamp, for example, measurement with an illuminometer (irradiance intensity meter UM-10 manufactured by Konica Minolta Sensing, light receiving unit UM-360 [peak sensitivity wavelength: 365 nm, measurement wavelength range: 310 to 400 nm]) 100 mW / cm ² or more is preferable in value, 200 mW / cm ² or more is particularly preferable. When the irradiation intensity is less than 100 mW / cm ² , it takes a long time to remove the protective film 10. Further, a low-pressure mercury lamp is preferable because it can irradiate ultraviolet rays having a shorter wavelength, and thus the protective film 10 can be removed in a short time even if the irradiation intensity is low.

Further, when the protective film 10 is removed by light irradiation, if the constituent components of the protective film 10 are decomposed by ultraviolet rays and ozone is generated at the same time, and the constituent components of the protective film 10 are oxidized and volatilized by the ozone, the processing time is shortened. Therefore, it is particularly preferable. As this light source, a low-pressure mercury lamp, an excimer lamp, or the like is used. Further, the wafer may be heated while irradiating light.

When heating the wafer, it is preferable to heat the wafer at 400 to 1000 ° C., preferably 500 to 900 ° C. This heating time is preferably maintained for 10 seconds to 60 minutes, preferably 30 seconds to 10 minutes. In this process, ozone exposure, plasma irradiation, corona discharge, etc. may be used in combination. Further, light irradiation may be performed while heating the wafer.

There are a method of removing the protective film 10 by heating, a method of bringing the wafer into contact with a heat source, and a method of placing the wafer in a heated atmosphere such as a heat treatment furnace. Note that the method of placing the wafer in a heated atmosphere is easy to operate because it is easy to uniformly apply energy for removing the protective film 10 to the wafer surface even when processing a plurality of wafers. This is an industrially advantageous method that requires a short processing time and a high processing capacity.

When the wafer is exposed to ozone, it is preferable that ozone generated by ultraviolet irradiation with a low-pressure mercury lamp or the like or low-temperature discharge with a high voltage is provided on the wafer surface. The wafer may be irradiated with light while being exposed to ozone, or may be heated.

By combining the above light irradiation, heating, ozone exposure, plasma irradiation, and corona discharge, the protective film on the wafer surface can be efficiently removed.

Hereinafter, examples that more specifically disclose the embodiment of the present invention will be shown. In addition, this invention is not limited only to these Examples.

Forming a concavo-convex pattern on the surface of a wafer and replacing the cleaning liquid held in at least the concave part of the concavo-convex pattern with other cleaning liquids are techniques already established through various studies in other literature. Therefore, in this invention, it evaluated about the water-repellent provision effect of the chemical | medical solution for protective film formation, and the tolerance with respect to this chemical | medical solution of a vinyl chloride resin. In the examples, water, which is a typical water-based cleaning liquid, was used as the liquid to be brought into contact with the wafer surface when the contact angle was evaluated.

However, in the case of a wafer having a concavo-convex pattern on the surface, the contact angle of the protective film 10 itself formed on the concavo-convex pattern surface cannot be accurately evaluated. The contact angle of water droplets is evaluated by dropping several microliters of water droplets on the surface of the sample (base material) as described in JIS R 3257 “Testing method for wettability of substrate glass surface”. It is made by measuring. However, in the case of a wafer having a pattern, the contact angle becomes very large. This is because a Wenzel effect and a Cassie effect occur, and the contact angle is affected by the surface shape (roughness) of the substrate, and the apparent contact angle of water droplets increases.

Therefore, in this embodiment, the above chemical solution is applied to a wafer having a smooth surface, a protective film is formed on the wafer surface, and the protective film is formed on the surface of the wafer having a concavo-convex pattern formed on the surface. Various evaluations were made. In this example, as a wafer having a smooth surface, a “wafer with SiO ₂ film” having a SiO ₂ layer on a silicon wafer having a smooth surface was used.

Details are described below. Hereinafter, an evaluation method, preparation of a protective film forming chemical solution, a wafer cleaning method using the protective film forming chemical solution, and evaluation results will be described.

〔Evaluation methods〕
The following (A) to (C) were evaluated.

(A) Contact angle evaluation of the protective film formed on the wafer surface About 2 μl of pure water is placed on the wafer surface on which the protective film is formed, and the angle (contact angle) formed between the water droplet and the wafer surface is measured by a contact angle meter (Kyowa). It was measured by Interface Science: CA-X type.

(B) Contact angle decrease at the time of water contact The amount of decrease in the contact angle was evaluated when the wafer on which the protective film was formed was immersed in 60 ° C warm water for 10 minutes. A smaller contact angle decrease means that the contact angle is less likely to be reduced by washing after the formation of the protective film, and the decrease is particularly preferably 10 ° or less.

(C) Resistance of the vinyl chloride resin to the chemical solution for forming the protective film In the embodiment of the present invention, whether or not the liquid contact member is deteriorated when the wafer is cleaned by a wafer cleaning apparatus containing the vinyl chloride resin as the liquid contact member. Instead of evaluating, the presence or absence of deterioration of the vinyl chloride resin was evaluated by immersing the vinyl chloride resin in the chemical solution for forming the protective film. Specifically, after immersing a vinyl chloride resin (the surface is glossy) in a chemical solution for forming a protective film and immersing it at 40 ° C. for 4 weeks, the deterioration of the vinyl chloride resin is visually observed, and discoloration, swelling, etc. The presence or absence of deterioration was confirmed. Those with no deterioration were accepted and those with no deterioration were rejected.

[Example 1]
(1) Preparation of protective film-forming chemical solution (I) Trimethylmethoxysilane [(CH ₃ ) ₃ Si—OCH ₃ ]; 5 g, (II) Diisoamyl ether [(CH ₃ ) ₂ CHCH ₂ CH ₂ —O -CH ₂ CH ₂ CH (CH ₃ ) ₂ : DiAE]; 94.8 g, (III), methyl trifluoromethanesulfonate [CF ₃ S (═O) ₂ OCH ₃ ]; A forming solution was obtained.
(2) Cleaning of silicon wafer A silicon wafer with a smooth thermal oxide film (Si wafer having a 1 μm thick thermal oxide film layer on the surface) is immersed in a 1% by mass hydrofluoric acid aqueous solution at room temperature for 10 minutes, and is then added to pure water. It was immersed in 2-propanol (iPA) for 1 minute at room temperature and for 1 minute at room temperature.
(3) Surface treatment of the silicon wafer surface with the chemical solution for forming the protective film The cleaned silicon wafer is added to the protective film forming chemical solution prepared in the above-mentioned “(1) Preparation of the chemical solution for forming the protective film” at room temperature for 2 minutes. It was immersed, and immersed in iPA at room temperature for 1 minute and in pure water at room temperature for 1 minute. Finally, the silicon wafer was taken out from the pure water and air was blown to remove the pure water on the surface.
When evaluated in the manner described in the above (A) to (C), as shown in Table 1, the initial contact angle before the surface treatment was less than 10 °, but the contact angle after the surface treatment was 82 °. The water repellency imparting effect was exhibited. Further, the decrease in the contact angle was 2 °, and the ease of maintaining water repellency was good. Furthermore, the resistance of the vinyl chloride resin was good with no change in appearance even after immersion for 4 weeks at 40 ° C.

[Examples 2 to 45]
The surface treatment of the wafer is performed in the same manner as in Example 1 except that the conditions such as the type and concentration of (I), the type and concentration of (III), and the type of (II) used in Example 1 are changed. Further evaluation was performed. The results of Examples 2 to 45 are shown in Tables 1 and 2.
In the table, “DnAE” means dinormal amyl ether, “DnHE” means dinormal hexyl ether, “EME” means ethyl methyl ether, “DnDE” means dinormal decyl ether. “DiAE / PGMEA-95” means a mixed solvent of DiAE: PGMEA (propylene glycol monomethyl ether acetate) = 95: 5 by mass ratio, and “DiAE / PGMEA-90” means DiAE: PGMEA = mass ratio 90:10 means a mixed solvent, “DiAE / nHA-95” means a mixed solvent of DiAE: nHA (n-hexanol) = 95: 5 by mass ratio, and “DiAE / ethyl acetate-95” means a mass This means a mixed solvent of DiAE: ethyl acetate = 95: 5 by ratio, and “DiAE / cyclohexanone-95” DiAE: cyclohexanone in a quantitative ratio means a mixed solvent of 95: 5, “decane / PGMEA-95” means a mixed solvent of decane: PGMEA = 95: 5 in a mass ratio, and “decane / nHA-95” means “Decan / nHA-90” means a mixed solvent of decane: nHA = 95: 5 by mass ratio, “decane / nHA-90” means a mixed solvent of decane: nHA = 90: 10 by mass ratio, and “1-dodecanethiol / PGMEA— “95” means a mixed solvent having a mass ratio of 1-dodecanethiol: PGMEA = 95: 5, and “decane / octamethyltrisiloxane-95” means a mixed solvent having a mass ratio of decane: octamethyltrisiloxane = 95: 5. “Decane / DiAE-95” means a mixed solvent of decane: DiAE = 95: 5 by mass ratio.

[Examples 46 to 51]
Additives were added to the chemical solution for forming a protective film in which the conditions such as the type and concentration of (I), the type and concentration of (III), and the type of (II) used in Example 1 were changed. The wafer was surface-treated in the same manner as described above and further evaluated. The results of Examples 46 to 51 are shown in Table 3.
In the table, “BHT” means dibutylhydroxytoluene, and “tert-butylxylenol” means 6-tert-butyl-2,4-xylenol.

In any of the examples, the initial contact angle before the surface treatment was less than 10 °, which showed the effect of imparting water repellency after the surface treatment. Further, the decrease in contact angle was slight, and the ease of maintaining water repellency was good. Furthermore, the resistance of the vinyl chloride resin was good with no change in appearance even after immersion for 4 weeks at 40 ° C.

In addition, (I) used in Example 5 is a structure in which one hydrogen atom is bonded to a silicon atom (that is, a structure in which b in the general formula [1] is 1), and the contact angle is reduced when contacted with water. It was confirmed that the degree of is greater than that in Example 4 using (I) having a structure in which b in the general formula [1] is 0. Therefore, from the viewpoint of easy maintenance of water repellency after forming the protective film, the number (b) of —H groups in the alkoxysilane represented by the general formula [1] as (I) is 0. It turned out that it is more preferable.

When Examples 1, 20, and 21 are compared, the smaller the number of carbon atoms of the hydrocarbon group represented by R ¹ in the general formula [1] that is (I), the larger the contact angle after the surface treatment, It was found that a better water repellency-imparting effect can be obtained when it is present.

When Examples 1, 2, and 3 are compared, the contact angles after the surface treatment are in the order of Example 1> Example 2> Example 3 (monoalkoxysilane> dialkoxysilane> trialkoxysilane). From the viewpoint of the effect, it was found that (I) is preferably monoalkoxysilane. The same tendency can be confirmed from the comparison of Examples 31, 32, and 33.

When Examples 8 and 12 were compared, it was found that the sulfonic acid ester of (III) can obtain better water repellency imparting effect when R ^{3 in the} general formula [2] is a perfluoroalkyl group. Also showed general formula water repellency examples 15,22,23 is excellent both with sulfonic acid ester R ³ is a perfluoroalkyl group of [2] as (III).

In Example 24, sulfonimide was used as (III), and an excellent water repellency imparting effect was shown.

In Examples 25 and 26, a sulfonimide derivative was used as (III), and an excellent water repellency imparting effect was shown.

Examples 9, 10 and 11 using DiAE, DnAE and DnHE, respectively, as (II) were good evaluation results. Moreover, although Example 13 using EME as a solvent was a favorable evaluation result, since the volatility of the solvent was high, it was necessary to prepare the liquid while cooling in order to suppress the concentration change due to solvent volatilization. Moreover, although Example 14 using DnDE as a solvent was a favorable evaluation result, since the viscosity of the solvent was high, the stirring time for obtaining a uniform chemical solution for forming a water-repellent protective film tended to be long. .

Examples 15, 16, and 17 using decane, dodecane, and decalin as (II) were all good evaluation results. Moreover, although Example 18 using pentane as (II) was a good evaluation result, since the volatility of the solvent was high, it was necessary to prepare the solution while cooling in order to suppress the concentration change due to solvent volatilization. It was. Moreover, although Example 19 using pentadecane as (II) was a good evaluation result, the viscosity of the solvent is high, and thus the stirring time for obtaining a uniform chemical solution for forming a water-repellent protective film tends to be long. there were.

Moreover, also in Example 34 using dodecanethiol as (II), it was a favorable evaluation result.

Also, in Examples 35 to 45 using a mixed solvent as (II), all were good evaluation results.

Also, in Examples 46 to 51 in which a decane solvent was used as (II) and an additive was further added, all were good evaluation results.

[Comparative Examples 1 to 11]
As shown in Table 4, the conditions of the type (I), the type and concentration of (III), the type of (II), etc. were changed, and the surface treatment of the wafer was performed in the same manner as in Example 1 except that Furthermore, the evaluation was performed.
Comparative Example 1 is a case where a protective film-forming chemical solution not containing (III) was used. The contact angle after the surface treatment was as low as less than 10 °, and no water repellency imparting effect was observed.
Comparative Example 2 is a case where a chemical solution for forming a protective film containing methyl trifluoroacetate [CF ₃ C (═O) OCH ₃ ] instead of methyl trifluoromethanesulfonate was used. The contact angle was as low as less than 40 °, and the effect of imparting water repellency was insufficient.
Comparative Examples 3 and 4 were examples in which (II) of Comparative Examples 1 and 2 were changed to DiAE, and the evaluation results were the same as those of Comparative Examples 1 and 2, respectively.
Comparative Examples 5 and 6 were examples in which (II) of Comparative Examples 1 and 2 were changed to dodecanethiol, and the evaluation results were the same as those of Comparative Examples 1 and 2, respectively.
Comparative Examples 7 to 11 are examples using a water-repellent protective film-forming chemical solution in which the total amount of hydrocarbon, ether and thiol was 70% by mass with respect to the total amount of (II) of 100% by mass. In the evaluation of the resistance of the resin to the chemical solution for forming a protective film, the swelling of the vinyl chloride resin was confirmed after the immersion, which was unacceptable.

[Examples 52 to 56]
The surface treatment of the wafer was carried out in the same manner as in Example 25 except that the protective film forming chemical solution in which the type of (III) used in Example 25 was changed, and the evaluation was further performed. The results of Examples 52 to 56 are shown in Table 5. For comparison, the results of Example 25 are also shown in Table 5.

Example 25 using the sulfonimide derivative represented by the general formula [5] as (III) has a particularly excellent water repellency imparting effect as compared with Examples 52 to 55 using other (III). Indicated. Further, as (III), Example 56 in which the sulfonimide derivative represented by the general formula [5] and another compound were used in combination also showed an excellent water repellency imparting effect as compared with Examples 52-55. From the above results, when (III) contains at least a sulfonimide derivative represented by the general formula [5], a more excellent water repellency imparting effect can be expressed, and (III) is represented by the general formula [5]. It was confirmed that an excellent water repellency-imparting effect can be exhibited when the sulfonimide derivative is used.

[Examples 57 to 61]
The surface treatment of the wafer was carried out in the same manner as in Example 26 except that the protective film forming chemical solution in which the type of (III) used in Example 26 was changed, and the evaluation was further performed. The results of Examples 57 to 61 are shown in Table 5. For comparison, the results of Example 26 are also shown in Table 5.

Example 26 using the sulfonimide derivative represented by the general formula [5] as (III) has a particularly excellent water repellency imparting effect as compared with Examples 57 to 60 using the other (III). Indicated. Further, as (III), Example 61 in which the sulfonimide derivative represented by the general formula [5] and another compound were used in combination also showed an excellent water repellency imparting effect as compared with Examples 57-60. From the above results, when (III) contains at least a sulfonimide derivative represented by the general formula [5], a more excellent water repellency imparting effect can be expressed, and (III) is represented by the general formula [5]. It was confirmed that an excellent water repellency-imparting effect can be exhibited when the sulfonimide derivative is used.

[Examples 62 to 85]
Except that (CF ₃ S (═O) ₂ ) ₂ N—Si (CH ₃ ) ₃ was used as (III), the wafer surface was the same as in Examples 1 to 11, 13 to 21, and 27 to 30, respectively. The treatment was performed and further evaluated. The results of Examples 62 to 85 are shown in Table 6.

Examples (62) to (85) using the sulfonimide derivative represented by the general formula [5] as (III) were changed to Examples 1 to 11, 13 to 21, and 27 to 30 using (III) other than (III). In comparison, each of them exhibited particularly excellent water repellency imparting effects. From the above results, it was confirmed that when the (III) is a sulfonimide derivative represented by the general formula [5], a further excellent water repellency imparting effect can be expressed.

DESCRIPTION OF SYMBOLS 1 Wafer 2 Fine uneven | corrugated pattern on the wafer surface 3 Pattern convex part 4 Pattern concave part 5 Concave width 6 Convex height 7 Convex width 8 The protective film forming chemical 9 held in the concave part 4 In the concave part 4 Retained liquid 10 protective film

Claims

(I) a solvent containing at least one selected from the group consisting of alkoxysilanes represented by the following general formula [1], (II) hydrocarbons, ethers, and thiols in a proportion of 80 to 100% by mass; III) Sulfonic acid ester represented by the following general formula [2], sulfonimide represented by the following general formula [3] and [4], and sulfonimide derivative represented by the following general formula [5] and [6] A cleaning device containing a vinyl chloride resin as a wetted member, comprising at least one selected from the group consisting of a sulfonemethide represented by the following general formula [7] and a sulfonemethide derivative represented by the following general formula [8]: A chemical solution for forming a water-repellent protective film for cleaning a wafer to be used.

[In the formula [1], each R 1 is independently selected from monovalent hydrocarbon groups having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. At least one group, and R 2 is each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, a is an integer of 1 to 3, b is an integer of 0 to 2, and the sum of a and b is 3 or less. ]

[In the formula [2], R 3 is selected from the group consisting of monovalent hydrocarbon groups having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and fluorine elements. R 4 is a monovalent alkyl group having 1 to 18 carbon atoms. ]

[In the formula [3], R 5 are each independently a monovalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and It is a group selected from the group consisting of fluorine elements. ]

[In the formula [4], R 6 is a divalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. ]

[In the formula [5], each R 7 is independently of each other a monovalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and R 8 is a group selected from the group consisting of fluorine elements, and R 8 is each independently a monovalent carbon atom having 1 to 18 carbon atoms, in which some or all of the hydrogen elements may be replaced by fluorine elements A hydrogen group, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c and d is 3 or less. ]

[In the formula [6], R 9 s are each independently a divalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, R 10 s are each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and e is 1 to 3 An integer, f is an integer from 0 to 2, and the sum of e and f is 3 or less. ]

[In the formula [7], R 11 are each independently a monovalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and It is a group selected from the group consisting of fluorine elements. ]

[In the formula [8], R 12 are each independently a monovalent hydrocarbon group having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and R 13 is a group selected from the group consisting of fluorine elements, and each R 13 , independently of each other, is a monovalent carbon atom having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements A hydrogen group, g is an integer of 1 to 3, h is an integer of 0 to 2, and the sum of g and h is 3 or less. ]
The chemical solution for forming a water-repellent protective film according to claim 1, wherein (III) includes at least a sulfonimide derivative represented by the general formula [5].
The chemical solution for forming a water-repellent protective film according to claim 1, wherein (III) is a sulfonimide derivative represented by the general formula [5].
In the sulfonic acid ester, R 3 in the general formula [2] is a group selected from the group consisting of a perfluoroalkyl group having 1 to 6 carbon atoms and a fluorine element, and R 4 is a group having 1 to 8 carbon atoms. The chemical solution for forming a water-repellent protective film according to claim 1, which is a compound which is a monovalent alkyl group.
The sulfonimide is a compound in which R 5 in the general formula [3] is a group selected from the group consisting of a perfluoroalkyl group having 1 to 6 carbon atoms and a fluorine element, and the general formula [4] 2. The chemical solution for forming a water-repellent protective film according to claim 1, wherein R 6 is a compound selected from the group consisting of compounds having a C 1-6 perfluoroalkylene group.
The sulfonimide derivative is a compound in which R 7 in the general formula [5] is a group selected from the group consisting of a perfluoroalkyl group having 1 to 6 carbon atoms and a fluorine element. The liquid chemical for forming a water repellent protective film according to any one of the above.
2. The chemical solution for forming a water-repellent protective film according to claim 1, wherein the sulfonimide derivative is a compound in which R 9 in the general formula [6] is a perfluoroalkylene group having 1 to 6 carbon atoms.
2. The water repellency according to claim 1, wherein the sulfonemethide is a compound in which R 11 in the general formula [7] is a group selected from the group consisting of a C 1-6 perfluoroalkyl group and a fluorine element. Chemical solution for protective film formation.
The repellency according to claim 1, wherein the sulfonemethide derivative is a compound in which R 12 in the general formula [8] is a group selected from the group consisting of a perfluoroalkyl group having 1 to 6 carbon atoms and a fluorine element. A chemical solution for forming an aqueous protective film.
The chemical solution for forming a water-repellent protective film according to any one of claims 1 to 9, wherein the hydrocarbon is a hydrocarbon having 6 to 13 carbon atoms.
The chemical solution for forming a water-repellent protective film according to any one of claims 1 to 10, wherein the ether is an ether represented by the following general formula [9].

[In the formula [9], R 14 and R 15 are each independently a monovalent carbon atom having 1 to 8 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. It is a hydrogen group, and the total number of carbon atoms of R 14 and R 15 is 4 to 16. ]
The chemical solution for forming a water-repellent protective film according to any one of claims 1 to 11, wherein the thiol is a thiol having 6 to 13 carbon atoms.
The chemical solution for forming a water repellent protective film according to any one of claims 1 to 12, wherein (I) is at least one selected from the group consisting of alkoxysilanes represented by the following general formula [10].

[In the formula [10], R 16 are each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, R 17 Are each independently a monovalent hydrocarbon group having 1 to 12 carbon atoms, and i is 2 or 3. ]
The liquid chemical for forming a water repellent protective film according to any one of claims 1 to 13, wherein (I) is at least one selected from the group consisting of monoalkoxysilanes represented by the following general formula [11].

[In the formula [11], R 18 is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and R 19 has 1 carbon atom. Is a monovalent hydrocarbon group of ˜12. ]
The water-repellent protection according to any one of claims 1 to 14, wherein the concentration of (I) is from 0.5 to 35% by mass relative to 100% by mass of the total amount of (I), (II), and (III). Chemical solution for film formation.
The repellent according to any one of claims 1 to 15, wherein a concentration of the total amount of (III) with respect to 100% by mass of the total amount of (I), (II), and (III) is 0.0001 to 5% by mass. A chemical solution for forming an aqueous protective film.
A water repellent protective film-forming chemical solution kit for obtaining the water-repellent protective film-forming chemical solution according to any one of claims 1 to 16 by mixing, comprising at least the (I), or (I), containing at least one selected from the group consisting of hydrocarbons, ethers, and thiols, including the first liquid, and (III), or (III), hydrocarbons, ethers, And at least one selected from the group consisting of a hydrocarbon, an ether, and a thiol, wherein at least one of the first and second liquids includes at least one selected from the group consisting of thiols. A chemical solution kit for forming a water-repellent protective film.
A wafer cleaning method using a cleaning device containing a vinyl chloride resin as a liquid contact member, wherein the wafer surface is maintained by holding the chemical solution for forming a water repellent protective film according to any one of claims 1 to 16 on the wafer surface. A method for cleaning a wafer, comprising the step of forming a water-repellent protective film on the substrate.
After holding the water repellent protective film forming chemical in at least the recesses of the concave / convex pattern and forming the water repellent protective film on the concave surfaces, the water repellent protective film forming chemical is removed from the recesses by drying. The method for cleaning a wafer according to claim 18.
After holding the water repellent protective film forming chemical in at least the recesses of the concave / convex pattern and forming the water repellent protective film on the surface of the concaves, the water repellent protective film forming chemical is different from the chemicals. The method for cleaning a wafer according to claim 18, wherein the wafer is replaced with a cleaning liquid, and the cleaning liquid is removed from the recess by drying.
The wafer surface after the drying is subjected to at least one treatment selected from the group consisting of heat treatment, light irradiation treatment, ozone exposure treatment, plasma irradiation treatment, and corona discharge treatment to remove the water-repellent protective film. Item 21. The method for cleaning a wafer according to Item 19 or 20.
Containing at least (I), or containing (I) and at least one selected from the group consisting of hydrocarbons, ethers, and thiols, and containing (III), or , (III) and a second liquid containing at least one selected from the group consisting of hydrocarbons, ethers, and thiols, wherein at least one of the first liquid and the second liquid is a hydrocarbon, ether, The water-repellent protective film-forming chemical solution is obtained by mixing a water-repellent protective-film-forming chemical solution kit containing at least one selected from the group consisting of thiols. A method for cleaning a wafer according to claim 1.