KR20200108887A - Chemical liquid for forming a water-repellent protective film and a method for surface treatment of wafers - Google Patents

Abstract

[화학식 37]

The present invention provides a chemical for forming a water-repellent protective film that can further improve the water-repellent imparting effect. The chemical solution for forming a water-repellent protective film of the present invention,
(I) an aminosilane compound represented by the following general formula [1] and
(II) a silicon compound represented by the following general formula [2] and
(III) has an aprotic solvent,
The content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass.
[Formula 36]

[Formula 37]

Description

Chemical liquid for forming a water-repellent protective film and a method for surface treatment of wafers

The present invention relates to a chemical for forming a water-repellent protective film for forming a water-repellent protective film on the surface of a concave portion of a fine uneven pattern on the surface of a substrate (wafer), and a method for surface treatment of a wafer.

In semiconductor devices for networks and digital home appliances, higher performance, higher functionality, and lower power consumption are required. For this reason, circuit patterns are being miniaturized, and a problem due to an increase in the aspect ratio of the pattern due to the miniaturization of semiconductor devices is becoming more current. That is, after washing or rinsing, a phenomenon in which the pattern collapses when the gas-liquid interface passes through the pattern (hereinafter sometimes referred to as "pattern collapse") is caused, resulting in a significant decrease in the yield.

This pattern collapse occurs when the cleaning liquid or rinse liquid is dried and removed from the wafer surface. It is known that this is caused by a difference in the height of the remaining liquid between a portion having a high aspect ratio and a portion having a low aspect ratio of the pattern, thereby causing a difference in capillary force acting on the pattern. Therefore, by forming a water-repellent protective film on the pattern surface by replacing the cleaning liquid or the rinse liquid with a chemical liquid for forming a water-repellent protective film, if the capillary force acting on the pattern is reduced, the difference in capillary force due to the difference in the height of the remaining liquid is reduced, and the pattern The collapse can be expected to be resolved.

In Patent Document 1, the present applicant is for forming a water-repellent protective film on at least the surface of the concave portion of the uneven pattern when cleaning a wafer having a fine uneven pattern on the surface and at least a part of the uneven pattern containing a silicon element. As a chemical solution,

Including acidic silicon compound A and acid A represented by the following general formula,

The acid A is trimethylsilyltrifluoroacetate, trimethylsilyltrifluoromethanesulfonate, dimethylsilyltrifluoroacetate, dimethylsilyltrifluoromethanesulfonate, butyldimethylsilyltrifluoroacetate, butyldimethylsilyltrifluoro Methanesulfonate, hexyldimethylsilyltrifluoroacetate, hexyldimethylsilyltrifluoromethanesulfonate, octyldimethylsilyltrifluoroacetate, octyldimethylsilyltrifluoromethanesulfonate, decyldimethylsilyltrifluoroacetate, and, It is at least one selected from the group consisting of decyldimethylsilyltrifluoromethanesulfonate,

Disclosed is a chemical liquid for forming a water repellent protective film, and a wafer cleaning method using the chemical liquid, characterized in that the total amount of water in the starting material of the chemical liquid is 100 mass ppm or less with respect to the total amount of the raw material.

[Formula 1]

(R is each independently of each other, at least one group selected from a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms, and a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms And X is each independently a monovalent organic group in which the element bonded to the Si element is nitrogen, a is an integer of 1 to 3, b is an integer of 0 to 2, and the sum of a and b is 1 to It is 3.)

Japanese Patent No. 58231844

In semiconductor device manufacturing, in particular, in a substrate (wafer) cleaning technology for the purpose of improving the manufacturing yield of a circuit patterned device having a fine and high aspect ratio, a chemical solution for forming a water-repellent protective film is being developed. The chemical liquid for forming a protective film described in Patent Document 1 clearly exhibits excellent water repellency imparting effect, and has excellent storage stability of the chemical liquid because the total amount of moisture in the starting material of the chemical liquid is 100 mass ppm or less with respect to the total amount of the raw material. will be. However, in recent years, the tendency of semiconductor devices to be highly integrated and micronized has been increasing, and wafer patterns are being made to be finer and higher in aspect ratio, so that the chemical solution for forming a water-repellent protective film that reduces pattern collapse further improves the effect of imparting water repellency. This is desired.

The present invention,

(I) an aminosilane compound represented by the following general formula [1] and

(II) a silicon compound represented by the following general formula [2] and

(III) has an aprotic solvent,

A chemical solution for forming a water-repellent protective film, wherein the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass (hereinafter, it may be simply described as ``a chemical solution for forming a protective film'' or a ``chemical solution'') to be.

[Formula 2]

[In formula [1], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. a is an integer of 1 to 3, b is an integer of 0 to 2, and the sum of a and b is 1 to 3.]

[Formula 3]

[In formula [2], R ² is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. In addition, X is a halogen group, -OC(=O)R ³ , -OS(=O) ₂ -R ³ , -N(S(=O) ₂ -R ³ ) ₂ , -C(S(=O ) ₂ -R ³ ) represents at least one group selected from the group consisting of ₃ . R ³ is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c and d is 1 to 3.]

Moreover, if the said (I) is a compound represented by the following general formula [3], since the said protective film can be formed homogeneously, it is more preferable.

[Formula 4]

[In formula [3], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]

It is preferable from the viewpoint of easiness of preparation of a chemical liquid that the said chemical liquid further contains a silazane compound represented by (IV) following general formula [4].

[Formula 5]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]

In addition, the content of (II) relative to the total amount of the above (I) to (III) is preferably 0.05% by mass or more from the viewpoint of improving the effect of imparting water repellency, and is preferably 20% by mass or less from the viewpoint of cost. .

In addition, it is preferable from the viewpoint of improving the effect of imparting water repellency that (II) is at least one compound selected from the group consisting of the following general formula [5].

[Formula 6]

[In formula [5], R ² is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element, and R ³ Silver is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms. In addition, g is an integer of 1 to 3.]

In the present invention, in a state in which at least one liquid selected from the group consisting of a cleaning liquid and a rinse liquid is held on the wafer surface, the liquid is replaced with a chemical for forming a water repellent protective film, and the chemical liquid is replaced on the wafer surface. As a surface treatment method of a wafer having a water-repellent protective film forming step and a drying step to be held on,

The chemical solution for forming a water-repellent protective film,

(I) an aminosilane compound represented by the following general formula [1] and

(II) a silicon compound represented by the following general formula [2] and

(III) has an aprotic solvent,

It is a wafer surface treatment method wherein the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass.

[Formula 7]

[In formula [1], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. a is an integer of 1 to 3, b is an integer of 0 to 2, and the sum of a and b is 1 to 3.]

[Formula 8]

[In formula [2], R ² is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. In addition, X is a halogen group, -OC(=O)R ³ , -OS(=O) ₂ -R ³ , -N(S(=O) ₂ -R ³ ) ₂ , -C(S(=O ) ₂ -R ³ ) represents at least one group selected from the group consisting of ₃ . R ³ is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c and d is 1 to 3.]

Moreover, if the said (I) is a compound represented by the following general formula [3], since the said protective film can be formed homogeneously, it is more preferable.

[Formula 9]

[In formula [3], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]

In the above method, it is preferable from the viewpoint of ease of preparation of the chemical liquid that the chemical liquid for forming a water-repellent protective film further contains a silazane compound represented by (IV) the following general formula [4].

[Formula 10]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]

In addition, the method, before the process of forming the water repellent protective film,

(II) a silicon compound represented by the general formula [2] and

(IV) a silazane compound represented by the following general formula [4] and

(III) In the raw material chemical solution having an aprotic solvent,

By contacting the protic compound in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (II), (III) and (IV),

Having a chemical solution preparation step of preparing a chemical solution for forming a water-repellent protective film in which the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass. It is preferable from the viewpoint of ease of preparation of a chemical solution.

[Formula 11]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]

In addition, the method, before the process of forming the water repellent protective film,

(II) a silicon compound represented by the general formula [2] and

(IV) a silazane compound represented by the following general formula [4] and

(III) In the raw material chemical solution having an aprotic solvent,

By contacting the protic compound in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (II), (III) and (IV),

Having the above (I) to (IV), and having a chemical solution preparation step of preparing a chemical solution for forming a water-repellent protective film in which the content of (I) is 0.02 to 0.5% by mass relative to the total amount of (I) to (III) It is preferable from the viewpoint of ease of preparation of a chemical solution.

[Formula 12]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]

Further, in the above method, if the chemical liquid preparation step is to bring the raw material chemical liquid into a space containing a protic compound and bring both of them into contact, it is preferable because it is easy to uniformly contact both. Further, the protic compound contained in the above space may be in a liquid state or a gaseous state. When the protonic compound is in a gaseous state, it is preferable to manage the concentration (volume %) of the protic compound in the space and the contact time.

Further, in the above method, the protic compound is preferably a compound having an -OH group and/or a -NH ₂ group from the viewpoint of improving the effect of imparting water repellency, and more preferably water and/or 2-propanol. It is preferred, and water is particularly preferred.

In addition, the method, before the process of forming the water repellent protective film,

(IV) a silazane compound represented by the following general formula [4] and

(III) In the raw material chemical solution having an aprotic solvent,

By contacting an acidic compound represented by the following general formula [6] in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (III) and (IV),

Having a chemical solution preparation step of preparing a chemical solution for forming a water-repellent protective film in which the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass. Since the number of raw materials to be used can be reduced, it is preferable from the viewpoint of cost.

[Formula 13]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]

[Formula 14]

[In formula [6], X is a halogen group, -OC(=O)R ³ , -OS(=O) ₂ -R ³ , -N(S(=O) ₂ -R ³ ) ₂ , -C (S(=O) ₂ -R ³ ) ₃ is shown. R ³ is a C 1 to C 6 monovalent perfluoroalkyl group.]

In addition, the method, before the process of forming the water repellent protective film,

(IV) a silazane compound represented by the following general formula [4] and

(III) In the raw material chemical solution having an aprotic solvent,

By contacting an acidic compound represented by the following general formula [6] in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (III) and (IV),

Having the above (I) to (IV), and having a chemical solution preparation step of preparing a chemical solution for forming a water-repellent protective film in which the content of (I) is 0.02 to 0.5% by mass relative to the total amount of (I) to (III) The number of raw materials to be used can be reduced, which is preferable from the viewpoint of cost.

[Formula 15]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]

[Formula 16]

[In formula [6], X is a halogen group, -OC(=O)R ³ , -OS(=O) ₂ -R ³ , -N(S(=O) ₂ -R ³ ) ₂ , -C (S(=O) ₂ -R ³ ) ₃ is shown. R ³ is a C 1 to C 6 monovalent perfluoroalkyl group.]

In the above method, the content of (II) with respect to the total amount of (I) to (III) is preferably 0.05% by mass or more from the viewpoint of improving the effect of imparting water repellency, and 20% by mass from the viewpoint of cost. The following are preferable.

Further, in the above method, if (II) is at least one compound selected from the group consisting of the following general formula [5], it is preferable from the viewpoint of improving the effect of imparting water repellency.

[Formula 17]

[In formula [5], R ² is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element, and R ³ Silver is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms. In addition, g is an integer of 1 to 3.]

Advantageous Effects of Invention According to the present invention, a chemical solution for forming a water-repellent protective film having a novel composition capable of exerting a more excellent water repellency imparting effect, and a method for surface treatment of a wafer using the chemical solution are provided.

1 is a flow chart of surface treatment mode 1. FIG.
2 is a flow chart of surface treatment mode 2.
3 is a flow chart of surface treatment mode 3.
4 is a flow chart of surface treatment mode 4.
5 is a flow chart of surface treatment mode 5.
6 is a flow chart of surface treatment mode 6.
7 is a plot (Comparative Example 1-1, Example 1-3, Example 1-2, Example 1-1, Comparative Example 1-2) of the contact angle after surface treatment with respect to the amount of hydrogenation.
8 is a plot of the contact angle after surface treatment with respect to the concentration of the aminosilane compound after hydrogenation (Comparative Example 1-1, Comparative Example 1-2, Example 1-3, Example 1-2, Example 1- 1).
9 is a plot of the contact angle after surface treatment with respect to the amount of iPA added (Comparative Example 1-1, Example 1-6, Example 1-5, Example 1-4, Comparative Example 1-3).
10 is a plot of the contact angle after surface treatment with respect to the concentration of the aminosilane compound after iPA addition (Comparative Example 1-1, Comparative Example 1-3, Example 1-6, Example 1-5, Example 1- 4).

1. Chemical liquid for forming water repellent protective film

The chemical liquid for forming a water-repellent protective film is used when forming a water-repellent protective film (hereinafter, simply referred to as a "protective film") on the surface of the object to be treated. The type of object to be processed is not particularly limited. As the object to be processed, a "substrate (wafer)" is preferable. Here, as the ``wafer'' to be processed, a wafer used for manufacturing a semiconductor device is exemplified, and ``the surface of the wafer'' refers to the surface of the inorganic pattern and resin pattern provided on the wafer in addition to the surface of the wafer itself, and the pattern The surface of the inorganic layer and the organic layer which are not formed are illustrated.

As the inorganic pattern provided on the wafer, a pattern formed by preparing an etching mask on the surface of an inorganic layer present on the wafer by a photoresist method and then performing an etching process is exemplified. Examples of the inorganic layer include, in addition to the wafer itself, oxide films of elements constituting the wafer, and films or layers of inorganic materials such as silicon nitride, titanium nitride, and tungsten formed on the surface of the wafer. Although it does not specifically limit as such a film|membrane or layer, The film|membrane, layer, etc. of inorganic materials formed in the manufacturing process of a semiconductor device are illustrated.

As a resin pattern provided on a wafer, a resin pattern formed on a wafer by a photoresist method is illustrated. Such a resin pattern is formed, for example, by forming an organic layer that is a film of a photoresist on a wafer, exposing the organic layer to light through a photomask, and developing. As the organic layer, in addition to the surface of the wafer itself, one provided on the surface of a laminated film provided on the surface of the wafer, etc. are illustrated. Although it does not specifically limit as such an organic layer, In the manufacturing process of a semiconductor device, the film of an organic material provided for forming an etching mask is illustrated.

The chemical solution of the present invention prepared in advance can be applied to the surface of an object to be processed such as a wafer by means such as a spin coating method or an immersion method, and can be held on the surface. In addition, the above-described chemical solution may be supplied to the surface of an object to be processed such as a wafer (hereinafter, referred to as "steam method"), and held thereon.

Furthermore, the raw material chemical is applied to the surface of an object to be processed such as a wafer by means such as spin coating, immersion or steam, and the protonic compound is brought into contact with the reaction to form a water-repellent protective film. It is also possible to prepare a chemical solution and hold it on the surface of the object to be treated.

In addition, in a space containing a protic compound in advance, the raw material chemical solution is applied to the surface of an object to be processed such as a wafer by means such as a spin coating method, an immersion method, or a vapor method, and a water-repellent protective film is carried out by a reaction described later. It is also possible to prepare a formation chemical solution and hold it on the surface of the object to be treated.

The chemical liquid for forming a water-repellent protective film of the present invention contains at least an (I) aminosilane compound, (II) a silicon compound, and (III) an aprotic solvent. Hereinafter, each component is demonstrated.

[(I) Aminosilane compound and (II) silicon compound]

R ¹ in the general formula [1] and R ² in the general formula [2] are a water-repellent functional group. And, when the -NH _{2 group} of the general formula [1] or the -X group of the general formula [2], for example, in the case of a wafer containing silicon, reacts with a silanol group on the wafer surface, and the water repellency The portion having a functional group is fixed to the wafer surface, thereby forming a water-repellent protective film on the wafer surface. By using both of the above (I) and (II), both react quickly with the wafer surface, and a more excellent water repellency imparting effect is obtained.

If R ¹ in the general formula [1] is a linear alkyl group, when a protective film is formed on the surface of the wafer as the object to be processed, it is preferable because it can impart more excellent water repellency to the surface.

As a specific example of the aminosilane compound represented by the general formula [1], for example, CH ₃ Si(NH ₂ ) ₃ , C ₂ H ₅ Si(NH ₂ ) ₃ , C ₃ H ₇ Si(NH ₂ ) ₃ , C ₄ H ₉ Si(NH ₂ ) ₃ , C ₅ H ₁₁ Si(NH ₂ ) ₃ , C ₆ H ₁₃ Si(NH ₂ ) ₃ , C ₇ H ₁₅ Si(NH ₂ ) ₃ , C ₈ H ₁₇ Si (NH ₂ ) ₃ , C ₉ H ₁₉ Si(NH ₂ ) ₃ , C ₁₀ H ₂₁ Si(NH ₂ ) ₃ , C ₁₁ H ₂₃ Si(NH ₂ ) ₃ , C ₁₂ H ₂₅ Si(NH ₂ ) ₃ , C ₁₃ H ₂₇ Si(NH ₂ ) ₃ , C ₁₄ H ₂₉ Si(NH ₂ ) ₃ , C ₁₅ H ₃₁ Si(NH ₂ ) ₃ , C ₁₆ H ₃₃ Si(NH ₂ ) ₃ , C ₁₇ H ₃₅ Si( NH ₂ ) ₃ , C ₁₈ H ₃₇ Si(NH ₂ ) ₃ , (CH ₃ ) ₂ Si(NH ₂ ) ₂ , C ₂ H ₅ Si(CH ₃ )(NH ₂ ) ₂ , (C ₂ H ₅ ) ₂ Si(NH ₂ ) ₂ , C ₃ H ₇ Si(CH ₃ )(NH ₂ ) ₂ , (C ₃ H ₇ ) ₂ Si(NH ₂ ) ₂ , C ₄ H ₉ Si(CH ₃ )(NH ₂ ) ₂ , (C ₄ H ₉ ) ₂ Si(NH ₂ ) ₂ , C ₅ H ₁₁ Si(CH ₃ )(NH ₂ ) ₂ , C ₆ H ₁₃ Si(CH ₃ )(NH ₂ ) ₂ , C ₇ H ₁₅ Si (CH ₃ )(NH ₂ ) ₂ , C ₈ H ₁₇ Si(CH ₃ )(NH ₂ ) ₂ , C ₉ H ₁₉ Si(CH ₃ )(NH ₂ ) ₂ , C ₁₀ H ₂₁ Si(CH ₃ )( NH ₂ ) ₂ , C ₁₁ H ₂₃ Si(CH ₃ )(NH ₂ ) ₂ , C ₁₂ H ₂₅ Si(CH ₃ )(NH ₂ ) ₂ , C ₁₃ H ₂₇ Si(CH ₃ )(NH ₂ ) ₂ , C ₁₄ H ₂₉ Si(CH ₃ )(NH ₂ ) ₂ , C ₁₅ H ₃₁ Si(CH ₃ )(NH ₂ ) ₂ , C ₁₆ H ₃₃ S i(CH ₃ )(NH ₂ ) ₂ , C ₁₇ H ₃₅ Si(CH ₃ )(NH ₂ ) ₂ , C ₁₈ H ₃₇ Si(CH ₃ )(NH ₂ ) ₂ , (CH ₃ ) ₃ SiNH ₂ , C ₂ H ₅ Si(CH ₃ ) ₂ NH ₂ , (C ₂ H ₅ ) ₂ Si(CH ₃ )NH ₂ , (C ₂ H ₅ ) ₃ SiNH ₂ , C ₃ H ₇ Si(CH ₃ ) ₂ NH ₂ , (C ₃ H ₇ ) ₂ Si(CH ₃ )NH ₂ , (C ₃ H ₇ ) ₃ SiNH ₂ , C ₄ H ₉ Si(CH ₃ ) ₂ NH ₂ , (C ₄ H ₉ ) ₃ SiNH ₂ , C ₅ H ₁₁ Si(CH ₃ ) ₂ NH ₂ , C ₆ H ₁₃ Si(CH ₃ ) ₂ NH ₂ , C ₇ H ₁₅ Si(CH ₃ ) ₂ NH ₂ , C ₈ H ₁₇ Si(CH ₃ ) ₂ NH ₂ , C ₉ H ₁₉ Si(CH ₃ ) ₂ NH ₂ , C ₁₀ H ₂₁ Si(CH ₃ ) ₂ NH ₂ , C ₁₁ H ₂₃ Si(CH ₃ ) ₂ NH ₂ , C ₁₂ H ₂₅ Si(CH ₃ ) ₂ NH ₂ , C ₁₃ H ₂₇ Si(CH ₃ ) ₂ NH ₂ , C ₁₄ H ₂₉ Si(CH ₃ ) ₂ NH ₂ , C ₁₅ H ₃₁ Si(CH ₃ ) ₂ NH ₂ , C ₁₆ H ₃₃ Si(CH ₃ ) ₂ NH ₂ , C ₁₇ H ₃₅ Si(CH ₃ ) ₂ NH ₂ , C ₁₈ H ₃₇ Si(CH ₃ ) ₂ NH ₂ , (CH ₃ ) ₂ Si(H)NH ₂ , CH ₃ Si(H) ₂ NH ₂ , (C ₂ H ₅ ) ₂ Si(H)NH ₂ , C ₂ H ₅ Si(H) ₂ NH ₂ , C ₂ H ₅ Si(CH ₃ )(H)NH ₂ , (C ₃ H ₇ ) ₂ Si(H)NH ₂ , C ₃ H ₇ Si(H) ₂ NH ₂ , CF ₃ CH ₂ CH ₂ Si(NH ₂ ) ₃ , C ₂ F ₅ CH ₂ CH ₂ Si(NH ₂ ) ₃ , C ₃ F ₇ CH ₂ CH ₂ Si(NH ₂ ) ₃ , C ₄ F ₉ CH ₂ CH ₂ Si(NH ₂ ) ₃ , C ₅ F ₁₁ CH ₂ CH ₂ Si(NH ₂ ) ₃ , C ₆ F ₁₃ CH ₂ CH ₂ Si(NH ₂ ) ₃ , C ₇ F ₁₅ CH ₂ CH ₂ Si(NH ₂ ) ₃ , C ₈ F ₁₇ CH ₂ CH ₂ Si(NH ₂ ) ₃ , CF ₃ CH ₂ CH ₂ Si(CH ₃ )(NH ₂ ) ₂ , C ₂ F ₅ CH ₂ CH ₂ Si(CH ₃ )(NH ₂ ) ₂ , C ₃ F ₇ CH ₂ CH ₂ Si(CH ₃ )(NH ₂ ) ₂ , C ₄ F ₉ CH ₂ CH ₂ Si(CH ₃ )(NH ₂ ) ₂ , C ₅ F ₁₁ CH ₂ CH ₂ Si(CH ₃ )(NH ₂ ) ₂ , C ₆ F ₁₃ CH ₂ CH ₂ Si(CH ₃ )(NH ₂ ) ₂ , C ₇ F ₁₅ CH ₂ CH ₂ Si(CH ₃ )(NH ₂ ) ₂ , C ₈ F ₁₇ CH ₂ CH ₂ Si(CH ₃ )(NH ₂ ) ₂ , CF ₃ CH ₂ CH ₂ Si(CH ₃ ) ₂ NH ₂ , C ₂ F ₅ CH ₂ CH ₂ Si(CH ₃ ) ₂ NH ₂ , C ₃ F ₇ CH ₂ CH ₂ Si( CH ₃ ) ₂ NH ₂ , C ₄ F ₉ CH ₂ CH ₂ Si(CH ₃ ) ₂ NH ₂ , C ₅ F ₁₁ CH ₂ CH ₂ Si(CH ₃ ) ₂ NH ₂ , C ₆ F ₁₃ CH ₂ CH ₂ Si (CH ₃ ) ₂ NH ₂ , C ₇ F ₁₅ CH ₂ CH ₂ Si(CH ₃ ) ₂ NH ₂ , C ₈ F ₁₇ CH ₂ CH ₂ Si(CH ₃ ) ₂ NH ₂ , CF ₃ CH ₂ CH ₂ Si( CH ₃ )(H)NH ₂ and the like.

In addition, in the general formula [1], when the number of -NH ₂ groups represented by 4-ab is 1, the protective film can be formed homogeneously, so it is more preferable.

In addition, if b is 0 in the general formula [1], it is preferable because water repellency is easily maintained even when washing (rinsing) after formation of a protective film described later is performed.

Further, R ¹ is more preferable if it is a combination of two -CH ₃ groups and one linear alkyl group, since the protective film can be formed homogeneously. In addition, it is particularly preferable that R ¹ is a 3 -CH ₃ group.

Moreover, the aminosilane compound represented by the said general formula [1] may be obtained by reaction.

The (I) aminosilane compound is 0.02 to 0.5% by mass based on the total amount of (I) to (III). When it is less than 0.02 mass%, further improvement of the effect of imparting water repellency cannot be achieved. Moreover, when it exceeds 0.5 mass %, since aminosilanes are liable to react with each other, preparation of a chemical solution becomes difficult. It is preferably 0.03 to 0.4% by mass, more preferably 0.03 to 0.3% by mass.

In addition, as a specific example of the silicon compound represented by the general formula [2], CH ₃ Si(OC(=O)CF ₃ ) ₃ , C ₂ H ₅ Si(OC(=O)CF ₃ ) ₃ , C ₃ H ₇ Si(OC(=O)CF ₃ ) ₃ , C ₄ H ₉ Si(OC(=O)CF ₃ ) ₃ , C ₅ H ₁₁ Si(OC(=O)CF ₃ ) ₃ , C ₆ H ₁₃ Si (OC(=O)CF ₃ ) ₃ , C ₇ H ₁₅ Si(OC(=O)CF ₃ ) ₃ , C ₈ H ₁₇ Si(OC(=O)CF ₃ ) ₃ , C ₉ H ₁₉ Si(OC (=O)CF ₃ ) ₃ , C ₁₀ H ₂₁ Si(OC(=O)CF ₃ ) ₃ , C ₁₁ H ₂₃ Si(OC(=O)CF ₃ ) ₃ , C ₁₂ H ₂₅ Si(OC(= O)CF ₃ ) ₃ , C ₁₃ H ₂₇ Si(OC(=O)CF ₃ ) ₃ , C ₁₄ H ₂₉ Si(OC(=O)CF ₃ ) ₃ , C ₁₅ H ₃₁ Si(OC(=O) CF ₃ ) ₃ , C ₁₆ H ₃₃ Si(OC(=O)CF ₃ ) ₃ , C ₁₇ H ₃₅ Si(OC(=O)CF ₃ ) ₃ , C ₁₈ H ₃₇ Si(OC(=O)CF ₃ ) ₃ , (CH ₃ ) ₂ Si(OC(=O)CF ₃ ) ₂ , C ₂ H ₅ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , (C ₂ H ₅ ) ₂ Si(OC (=O)CF ₃ ) ₂ , C ₃ H ₇ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , (C ₃ H ₇ ) ₂ Si(OC(=O)CF ₃ ) ₂ , C ₄ H ₉ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , (C ₄ H ₉ ) ₂ Si(OC(=O)CF ₃ ) ₂ , C ₅ H ₁₁ Si(CH ₃ )(OC(= O)CF ₃ ) ₂ , C ₆ H ₁₃ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₇ H ₁₅ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₈ H ₁₇ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₉ H ₁₉ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₁₀ H ₂₁ Si(CH ₃ )(OC( =O)CF ₃ ) ₂ , C ₁₁ H ₂₃ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₁₂ H ₂₅ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₁₃ H ₂₇ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₁₄ H ₂₉ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₁₅ H ₃₁ Si(CH ₃ )(OC( =O)CF ₃ ) ₂ , C ₁₆ H ₃₃ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₁₇ H ₃₅ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₁₈ H ₃₇ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , (CH ₃ ) ₃ SiOC(=O)CF ₃ , C ₂ H ₅ Si(CH ₃ ) ₂ OC(=O)CF ₃ , ( C ₂ H ₅ ) ₂ Si(CH ₃ )OC(=O)CF ₃ , (C ₂ H ₅ ) ₃ SiOC(=O)CF ₃ , C ₃ H ₇ Si(CH ₃ ) ₂ OC(=O)CF ₃ , (C ₃ H ₇ ) ₂ Si(CH ₃ )OC(=O)CF ₃ , (C ₃ H ₇ ) ₃ SiOC(=O)CF ₃ , C ₄ H ₉ Si(CH ₃ ) ₂ OC(= O)CF ₃ , (C ₄ H ₉ ) ₃ SiOC(=O)CF ₃ , C ₅ H ₁₁ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₆ H ₁₃ Si(CH ₃ ) ₂ OC( =O)CF ₃ , C ₇ H ₁₅ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₈ H ₁₇ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₉ H ₁₉ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₀ H ₂₁ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₁ H ₂₃ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₂ H ₂₅ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₃ H ₂₇ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₄ H ₂₉ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₅ H ₃₁ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₆ H ₃₃ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₇ H ₃₅ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₁₈ H ₃₇ Si(CH ₃ ) ₂ OC(=O)CF ₃ , (CH ₃ ) ₂ Si(H)OC(=O )CF ₃ , CH ₃ Si(H) ₂ OC(=O) CF ₃ , (C ₂ H ₅ ) ₂ Si(H)OC(=O)CF ₃ , C ₂ H ₅ Si(H) ₂ OC(= O)CF ₃ , C ₂ H ₅ Si(CH ₃ )(H)OC(=O)CF ₃ , (C ₃ H ₇ ) ₂ Si(H)OC(=O)CF ₃ , C ₃ H ₇ Si( H) ₂ OC(=O)CF ₃ , CF ₃ CH ₂ CH ₂ Si(OC(=O)CF ₃ ) ₃ , C ₂ F ₅ CH ₂ CH ₂ Si(OC(=O)CF ₃ ) ₃ , C ₃ F ₇ CH ₂ CH ₂ Si(OC(=O)CF ₃ ) ₃ , C ₄ F ₉ CH ₂ CH ₂ Si(OC(=O)CF ₃ ) ₃ , C ₅ F ₁₁ CH ₂ CH ₂ Si(OC (=O)CF ₃ ) ₃ , C ₆ F ₁₃ CH ₂ CH ₂ Si(OC(=O)CF ₃ ) ₃ , C ₇ F ₁₅ CH ₂ CH ₂ Si(OC(=O)CF ₃ ) ₃ , C ₈ F ₁₇ CH ₂ CH ₂ Si(OC(=O)CF ₃ ) ₃ , CF ₃ CH ₂ CH ₂ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₂ F ₅ CH ₂ CH ₂ Si (CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₃ F ₇ CH ₂ CH ₂ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₄ F ₉ CH ₂ CH ₂ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₅ F ₁₁ CH ₂ CH ₂ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₆ F ₁₃ CH ₂ CH ₂ Si(CH ₃ ) (OC(=O)CF ₃ ) ₂ , C ₇ F ₁₅ CH ₂ CH ₂ Si(CH ₃ )(OC(=O)CF ₃ ) ₂ , C ₈ F ₁₇ CH ₂ CH ₂ Si(CH ₃ )(OC (=O)CF ₃ ) ₂ , CF ₃ CH ₂ CH ₂ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₂ F ₅ CH ₂ C H ₂ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₃ F ₇ CH ₂ CH ₂ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₄ F ₉ CH ₂ CH ₂ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₅ F ₁₁ CH ₂ CH ₂ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₆ F ₁₃ CH ₂ CH ₂ Si(CH ₃ ) ₂ OC(=O )CF ₃ , C ₇ F ₁₅ CH ₂ CH ₂ Si(CH ₃ ) ₂ OC(=O)CF ₃ , C ₈ F ₁₇ CH ₂ CH ₂ Si(CH ₃ ) ₂ OC(=O)CF ₃ , CF ₃ A trifluoroacetoxysilane such as CH ₂ CH ₂ Si(CH ₃ )(H)OC(=O)CF ₃ , or the -OC(=O)CF ₃ group of the trifluoroacetoxysilane, a halogen group , -OC (= O) CF ₃ group other than the -OC (= O) R ³ _{group, -OS (= O) 2 -R} 3 group, -N (S (= O) 2 -R 3) 2 group, -C(S(=O) ₂ -R ³ ) ₃ group (R ³ is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms) substituted with a group.

In addition, when the number of -X groups represented by 4-c-d in the general formula [2] is 1, since the protective film can be formed homogeneously, it is more preferable.

Further, in the general formula [2], when d is 0, it is preferable because water repellency is easily maintained even when washing (rinsing) after formation of a protective film described later is performed.

Further, the R ² is more preferable if it is a combination of two -CH ₃ groups and one linear alkyl group, since the protective film can be formed homogeneously. In addition, it is particularly preferable that R ² is a 3 -CH ₃ group.

Moreover, the silicon compound represented by the said general formula [2] may be obtained by reaction.

In addition, the content of the silicon compound (II) relative to the total amount of (I) to (III) is preferably 0.05% by mass or more from the viewpoint of improving the effect of imparting water repellency, and 20% by mass or less from the viewpoint of cost. Do. It is more preferably 0.1 to 15% by mass, more preferably 0.2 to 10% by mass.

[(III) Aprotic solvent]

The chemical liquid for forming a water-repellent protective film of the present invention contains an aprotic solvent. By containing the aprotic solvent, it is possible to easily perform the surface treatment of the object to be treated by a spin coating method, an immersion method, or a steam method. In addition, it is easy to ensure storage stability of the chemical solution.

Examples of the aprotic solvent include hydrocarbons, esters, ethers, ketones, halogen-containing solvents, sulfoxide solvents, sulfone solvents, lactone solvents, carbonate solvents, and polyhydric alcohols. Among the derivatives, organic solvents such as those that do not have an OH group, a nitrogen element-containing solvent that does not have an NH group, a silicone solvent, a terpene-based solvent, or a mixture thereof are suitably used. Among them, hydrocarbons, esters, ethers, halogen-containing solvents, derivatives of polyhydric alcohols that do not have OH groups, or a mixture of them can form the protective film on the surface of the object in a short time. More preferable.

Examples of the hydrocarbons include n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-undecane, n-dodecane, n-tetradecane, n-hexadecane, n-octadecane , n-icosic acid, and branched hydrocarbons corresponding to their carbon number (e.g. isododecane, isocetane, etc.), cyclohexane, methylcyclohexane, decalin, benzene, toluene, xylene, (ortho-, meta- , Or para-)diethylbenzene, 1,3,5-trimethylbenzene, and the like, and examples of the esters include ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, N-pentyl acetate, i-pentyl acetate, n-hexyl acetate, n-heptyl acetate, n-octyl acetate, n-pentyl formate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, n butyric acid -Butyl, methyl n-octanoate, methyl decanoate, methyl pyruvate, ethyl pyruvate, n-propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, ethyl 2-oxobutanoate, dimethyl adipate, methyl 3-methoxypropionate , Ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl ethoxyacetate, etc. Examples of the ethers include di-n-propyl ether, ethyl-n-butyl ether, Di-n-butyl ether, ethyl-n-amyl ether, di-n-amyl ether, ethyl-n-hexyl ether, di-n-hexyl ether, di-n-octyl ether, and diiso corresponding to their carbon number Ether having a branched hydrocarbon group such as propyl ether and diisoamyl ether, dimethyl ether, diethyl ether, methyl ethyl ether, methylcyclopentyl ether, diphenyl ether, tetrahydrofuran, dioxane, etc. Examples of the ketones , Acetone, acetylacetone, methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, cyclohexanone, isophorone, and the like, and examples of the halogen-containing solvent include perfluorooctane, perfluorononane, perfluorocyclopentane , Perfluorocarbons such as perfluorocyclohexane and hexafluorobenzene, 1,1,1,3,3-pentafluorobutane, octafluorocylate Hydrofluorocarbons such as clopentane, 2,3-dihydrodecafluoropentane, Zeurora H (made by Nippon Xeon), methyl perfluoroisobutyl ether, methyl perfluorobutyl ether, ethyl perfluorobutyl ether , Hydrofluoroethers such as ethyl perfluoroisobutyl ether, AsahiClean AE-3000 (manufactured by Asahi Glass), Novec7100, Novec7200, Novec7300, Novec7600 (all manufactured by 3M), chlorocarbons such as tetrachloromethane, chloroform Chlorofluorocarbons such as hydrochlorocarbon and dichlorodifluoromethane, 1,1-dichloro-2,2,3,3,3-pentafluoropropane, 1,3-dichloro-1,1,2,2 Hydrochlorofluorocarbons such as ,3-pentafluoropropane, 1-chloro-3,3,3-trifluoropropene, 1,2-dichloro-3,3,3-trifluoropropene, purple Luoroether, perfluoropolyether, etc., and examples of the sulfoxide solvent include dimethyl sulfoxide, and examples of the sulfone solvent include dimethylsulfone, diethylsulfone, bis(2-hydroxyethyl) Sulfone, tetramethylene sulfone, and the like, and examples of the lactone-based solvent include β-propiolactone, γ-butyrolactone, γ-valerolactone, γ-hexanolactone, γ-heptanolactone, and γ-octano Lactone, γ-nonanolactone, γ-decanolactone, γ-undecanolactone, γ-dodecanolactone, δ-valerolactone, δ-hexanolactone, δ-octanolactone, δ-nonanolactone, δ-decanolactone, δ-undecanolactone, δ-dodecanolactone, ε-hexanolactone, and the like, and examples of the carbonate-based solvent include dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, and propylene carbonate. Examples of the polyhydric alcohol derivatives that do not have an OH group include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol monobutyl ether Acetate, ethylene glycol diacetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol diethyl ether, diethylene glycol butyl methyl ether, diethylene glycol Cold dibutyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol diacetate, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol Dibutyl ether, triethylene glycol butyl methyl ether, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether acetate, triethylene glycol monobutyl ether acetate, triethylene glycol diacetate, tetraethylene glycol dimethyl ether, tetraethylene glycol Diethyl ether, tetraethylene glycol dibutyl ether, tetraethylene glycol monomethyl ether acetate, tetraethylene glycol monoethyl ether acetate, tetraethylene glycol monobutyl ether acetate, tetraethylene glycol diacetate, propylene glycol dimethyl ether, propylene glycol diethyl Ether, propylene glycol dibutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol diacetate, dipropylene glycol dimethyl ether, dipropylene glycol methylpropyl ether, dipropylene glycol Diethyl ether, dipropylene glycol dibutyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monobutyl ether acetate, dipropylene glycol diacetate, tripropylene glycol dimethyl ether, tripropylene glycol Diethyl ether, tripropylene glycol dibutyl ether, tripropylene glycol monomethyl ether acetate, tripropylene glycol monoethyl ether acetate, tripropylene glycol monobutyl ether acetate, tripropylene glycol diacetate, tetrapropylene glycol dimethyl ether, tetrapropylene glycol Monomethyl ether acetate, tetrapropylene glycol diacetate, butylene glycol dimethyl ether, butylene glycol monomethyl ether acetate, butylene glycol diacetate, glycerin triacetate, 3-methoxybutyl acetate, 3-methyl-3-methoxy Examples of the nitrogen element-containing solvent that includes butyl acetate, 3-methyl-3-methoxybutyl propionate and the like and does not have an NH group include N,N-dime Tylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-propyl-2-pyrrolidone, 1,3-dimethyl-2- Imidazolidinone, 1,3-diethyl-2-imidazolidinone, 1,3-diisopropyl-2-imidazolidinone, triethylamine, pyridine, and the like. Examples of silicone solvents include hexamethyl Disiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane, and the like, and examples of terpene-based solvents include p-mentane, diphenylmentane, limonene, terpinene, bornane, norbornane, pinan, etc. There is this.

In addition, when a solvent having a flash point exceeding 70°C is used as the aprotic solvent, it is preferable from the viewpoint of safety in the fire fighting method. For example, among carbonate-based solvents and derivatives of polyhydric alcohols, those having no OH group are preferable because many of them have a high flash point, so that the risk of a chemical solution can be reduced. From the above safety point of view, specifically, propylene carbonate, ethylene glycol dibutyl ether, ethylene glycol monobutyl ether acetate, ethylene glycol diacetate, diethylene glycol ethyl methyl ether, diethylene glycol diethyl Ether, diethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol diacetate, triethylene glycol dimethyl Ether, triethylene glycol diethyl ether, triethylene glycol dibutyl ether, triethylene glycol butyl methyl ether, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether acetate, triethylene glycol monobutyl ether acetate, triethylene glycol Diacetate, tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol dibutyl ether, tetraethylene glycol monomethyl ether acetate, tetraethylene glycol monoethyl ether acetate, tetraethylene glycol monobutyl ether acetate, tetraethylene glycol Diacetate, Propylene glycol diacetate, Dipropylene glycol methylpropyl ether, Dipropylene glycol monomethyl ether acetate, Dipropylene glycol monoethyl ether acetate, Dipropylene glycol monobutyl ether acetate, Dipropylene glycol diacetate, Tripropylene glycol dimethyl ether , Tripropylene glycol diethyl ether, tripropylene glycol dibutyl ether, tripropylene glycol monomethyl ether acetate, tripropylene glycol monoethyl ether acetate, tripropylene glycol monobutyl ether acetate, tripropylene glycol diacetate, tetrapropylene glycol dimethyl ether , Tetrapropylene glycol monomethyl ether acetate, tetrapropylene glycol diacetate, butylene glycol diacetate, glycerin triacetate, and the like are more preferably used as the solvent.

The chemical liquid for forming a water-repellent protective film of the present invention may further contain additives such as a polymerization inhibitor, a chain transfer agent, and an antioxidant in order to further increase the stability of the chemical liquid.

Further, it is preferable that the number of particles larger than 0.2 µm in the measurement of particles in the light scattering liquid in the liquid phase in the chemical liquid by a particle detector is 100 or less per 1 mL of the chemical liquid. If the number of particles larger than 0.2 μm is more than 100 per 1 mL of the chemical solution, the particles may cause pattern damage to the wafer to be processed, resulting in a decrease in device yield and reliability, which is not preferable. . In addition, if the number of particles larger than 0.2 μm is 100 or less per 1 mL of the chemical solution, cleaning (rinsing) of the wafer surface (the surface of the protective film) with a solvent or water after forming the protective film can be omitted or reduced. desirable. Further, the smaller the number of particles larger than 0.2 µm is, the more preferable, but within the above content range, there may be one or more per 1 mL of the chemical solution.

In addition, particle measurement in a liquid phase in a chemical solution in the present invention is measured using a commercially available measuring device in a particle measurement method in a light scattering liquid using a laser as a light source, and the particle diameter of the particle is PSL (polystyrene Latex) means the equivalent diameter of light scattering based on standard particles.

Here, the particles are particles such as dust, dust, organic solids, inorganic solids, etc. that are included as impurities in the raw material, or particles such as dust, dust, organic solids, inorganic solids, etc. that enter as contaminants during preparation of the chemical solution, and finally This corresponds to those that do not dissolve in the chemical solution and exist as particles.

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 0.1 mass ppb each with respect to the total amount of the chemical solution. It is preferable that it is the following. If the content of the metal impurities exceeds 0.1 mass ppb with respect to the total amount of the chemical, there is a concern that the junction leakage current of the device may increase, resulting in a decrease in the yield and reliability of the device, which is not preferable. In addition, if the metal impurity content is 0.1 mass ppb or less with respect to the total amount of the chemical solution, cleaning (rinsing) the wafer surface (protective film surface) with a solvent or water after the protective film is formed on the wafer surface to be processed. It is preferable because it can be omitted or reduced. For this reason, the smaller the metal impurity content is, the more preferable it is, but within the above content range, it may be 0.001 mass ppb or more for each element with respect to the total amount of the chemical solution.

2. Wafer Surface Treatment Method

In the surface treatment method of the present invention, while at least one liquid selected from the group consisting of a cleaning liquid and a rinse liquid is held on the wafer surface, the liquid is replaced with a chemical liquid for forming a water repellent protective film, and the chemical liquid is replaced on the wafer surface. It has a water-repellent protective film formation process to hold|maintain to, and a drying process,

The chemical solution for forming a water-repellent protective film,

(I) an aminosilane compound represented by the general formula [1] and

(II) a silicon compound represented by the general formula [2] and

(III) has an aprotic solvent,

It is characterized in that the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass.

(Surface treatment aspect 1)

As shown in Fig. 1, at least, (I), (II), and (III) are mixed to form a solution (a chemical for forming a water-repellent protective film), and the chemical is supplied to the wafer surface in a liquid state or a gas state, A liquid chemical for forming a water-repellent protective film is held on the wafer surface.

The supply of the chemical liquid is performed while a liquid such as a cleaning liquid or a rinse liquid is held on the wafer surface, and the liquid is replaced with a chemical liquid. At the time of substitution, there is no particular limitation as a liquid such as a cleaning liquid or a rinse liquid held on the wafer surface, but 2-propanol (iPA) or the like is generally used.

By the above substitution, the chemical solution is held on the wafer surface to form a water-repellent protective film on the wafer surface. If necessary, the chemical liquid on the wafer surface may be replaced with a rinse liquid to further perform a rinse treatment.

Then, the liquid is removed from the wafer surface by drying. Since the water-repellent protective film is formed on the wafer surface, it is possible to reduce pattern collapse during drying due to excellent water repellency.

In addition, examples of the liquid removed by drying include the chemical liquid for forming a water-repellent protective film, a rinse liquid, or a mixture thereof. In addition, when the liquid to be removed is a rinse liquid, the chemical liquid is replaced with a rinse liquid and a rinse treatment is further performed. In addition, when the liquid to be removed is a mixture of the chemical liquid and the rinse liquid, the liquid may be a ``mixed liquid'' in the middle of substituting the chemical liquid with the rinse liquid, and a ``mixed liquid'' in which the chemical liquid raw material is previously dissolved in the rinse liquid is used. It may be a case in which the chemical solution is substituted. The same applies to the surface treatment aspects 2 to 6 described later.

In addition, in the surface treatment aspect 1, the order of mixing (I) to (III) which is the raw material of the chemical liquid is not particularly limited, but it is preferable to mix (I) or (II) with the (III) aprotic solvent. Do.

In addition, the surface treatment method of the present invention, before the water-repellent protective film forming step,

(II) a silicon compound represented by the general formula [2] and

(IV) a silazane compound represented by the general formula [4] and

(III) In the raw material chemical solution having an aprotic solvent,

By contacting the protic compound in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (II), (III) and (IV),

Formation of a water-repellent protective film having the above (I) to (III) or the above (I) to (IV), wherein the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5 mass% It may further have a chemical solution preparation step of preparing a solution.

The method of bringing the protonic compound into contact with the raw material chemical is not particularly limited, and a known method can be employed. In addition, when preparing the chemical solution for forming a water-repellent protective film by the above contact, the details are unclear, but the reaction produced by the reaction of the silicon compound represented by the general formula [2] and the protic compound (AH) as shown in the following reaction formula When the product (XH; acidic compound) reacts with the silazane compound represented by the general formula [4], an aminosilane compound represented by the general formula [1] is produced. As a result, the (I) to ( III), or having the above (I) to (IV), and the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass. I can.

[Formula 18]

As this surface treatment method, surface treatment modes 2 to 3 described later can be employed.

(Surface treatment mode 2)

As shown in Fig. 2, at least, (II), (III), and (IV) are mixed to form a solution (raw chemical liquid), and a protic compound is added to the raw chemical liquid, (II), (III), ( A chemical solution for forming a water-repellent protective film is prepared by contacting at a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of IV). The protic compound used for the contact may be diluted with an aprotic solvent (in a state in which it is dispersed when not compatible). Examples of the aprotic solvent used for the dilution include those described as (III) of the present invention.

The raw material chemical liquid and the protonic compound used in the chemical liquid preparation step may be in a liquid state or a gaseous state. For example, a liquid state may be mixed in a container in a chamber, a tank, or a pipe after a confluence point, or a gaseous state may be mixed in a chamber, a vaporization chamber, or a pipe after a confluence point after vaporization. The liquid raw material chemical liquid in the inner container may be exposed to a gaseous protic compound to be brought into contact. Moreover, (I) may be contained in the said raw material chemical liquid.

The protic compound is preferably a compound having an -OH group and/or a -NH ₂ group from the viewpoint of improving the effect of imparting water repellency, and a compound having an -OH group, and/or NH ₃ is particularly preferable. . Further, water and/or an alcohol having 6 or less carbon atoms is preferable, and particularly preferably water and/or 2-propanol.

Examples of the alcohol having 6 or less carbon atoms include methanol, ethanol, linear or branched chain, propanol, butanol, pentanol, and hexanol, as well as a polyhydric alcohol or a derivative of a polyhydric alcohol having an OH group. Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1, Examples of derivatives of polyhydric alcohols including 4-butanediol and glycerin, and having -OH groups include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, and propylene glycol monomethyl ether , Propylene glycol monoethyl ether, propylene glycol monopropyl ether, butylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and the like.

In addition, when the protic compound is contacted in a proportion of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (II), (III) and (IV), the total amount of (I) to (III) in the chemical solution for forming a water repellent protective film It is preferable because the content of (I) is easily controlled to 0.02 to 0.5% by mass. The ratio of contacting the protic compound is more preferably 0.003 to 0.2 mol, particularly preferably 0.003 to 0.1 mol.

Then, the obtained chemical liquid is supplied to the wafer surface in a liquid state or a gaseous state, so that the liquid chemical for forming a water-repellent protective film is held on the wafer surface. In addition, since (I) aminosilane is produced by the reaction as described above, a chemical solution in a state in which the content of (I) with respect to the total amount of (I) to (III) is in the range of 0.02 to 0.5% by mass is applied to the wafer surface. To supply. On the other hand, since it is easy to ignore the influence on the composition of the chemical liquid such as side reactions, it is preferable to supply the chemical liquid within 1 day from the contact to the wafer surface, and supply the chemical liquid within 5 hours from the contact to the wafer surface. It is more preferable, and it is particularly preferable to supply the chemical solution within 1 hour from the contact to the wafer surface.

The supply of the chemical liquid is performed while a liquid such as a cleaning liquid or a rinse liquid is held on the wafer surface, and the liquid is replaced with a chemical liquid. In addition, when the liquid such as the washing liquid or the rinse liquid is a protic compound, the protic compound is further brought into contact in the process of the substitution as described above, and the (II) and the protic compound react, and the reaction product ( There is a possibility that the (I) is newly formed by further reacting the acidic compound) with the (IV). However, in the above substitution, since the liquid such as the washing liquid or the rinse liquid is rapidly substituted with the chemical liquid for forming a water-repellent protective film, the reaction between the (II) and the protic compound has little effect. Therefore, at the time of the above substitution, the effect of newly generated (I) as described above is negligible. At the time of substitution, there is no particular limitation as a liquid such as a cleaning liquid or a rinse liquid held on the wafer surface, but 2-propanol (iPA) or the like is generally used.

By the above substitution, the chemical solution is held on the wafer surface to form a water-repellent protective film on the wafer surface. If necessary, the chemical liquid on the wafer surface may be replaced with a rinse liquid to further perform a rinse treatment.

Then, the liquid is removed from the wafer surface by drying. Since the water-repellent protective film is formed on the wafer surface, it is possible to reduce pattern collapse during drying due to excellent water repellency. In addition, examples of the liquid removed by drying include the chemical liquid for forming a water-repellent protective film, a rinse liquid, or a mixture thereof.

(Surface treatment mode 3)

As shown in Fig. 3, at least, (II), (III), and (IV) are mixed to form a solution (raw chemical liquid), and the raw chemical liquid is supplied to the wafer surface in a liquid state or a gaseous state, and the wafer The liquid raw material chemical solution is held on the surface.

The supply of the chemical raw material is performed while a liquid such as a cleaning liquid or a rinse liquid is held on the wafer surface, and the liquid is replaced with the chemical raw material. In addition, when the liquid such as the washing liquid or the rinse liquid is a protic compound such as water or alcohol, the (II) and the protic compound react in the process of the above substitution, and the reaction product (acid compound) is added. There is a possibility that (I) is produced by reacting with (IV) above. However, in the above substitution, since the liquid such as the washing solution or the rinse solution is rapidly substituted with the raw material chemical solution, there is little effect of the reaction of the (II) and the protic compound. Therefore, at the time of the above substitution, the effect of newly generated (I) as described above is negligible. At the time of substitution, there is no particular limitation as a liquid such as a cleaning liquid or a rinse liquid held on the wafer surface, but 2-propanol (iPA) or the like is generally used.

Next, a protic compound is brought into contact with the raw material chemical solution at a ratio of 0.001 to 0.3 moles per 1 kg of the total amount of (II), (III), and (IV) to prepare a chemical solution for forming a water-repellent protective film on the wafer surface. . In addition, since (I) aminosilane is produced by the reaction as described above, the chemical solution is held on the wafer surface so that the content of (I) with respect to the total amount of (I) to (III) is in the range of 0.02 to 0.5% by mass. do.

The protic compound used for the above contact may be diluted with an aprotic solvent (in a disperse state when not compatible). Examples of the aprotic solvent used for the dilution include those described as (III) of the present invention. The protic compound used in the chemical solution preparation step may be in a liquid state or a gaseous state. For example, a liquid protonic compound may be added to the liquid raw material chemical liquid held on the wafer surface in the chamber, or the liquid raw material chemical liquid held on the wafer surface in the chamber may be gaseous. It may be exposed to the compound and brought into contact. In the latter case, for example, a raw material chemical solution may be supplied by placing the inside of the chamber in a vapor atmosphere of a protonic compound having a predetermined concentration.

In addition, when the raw material chemical liquid and the gaseous protic compound are brought into contact, the contact area can be increased by spreading the liquid raw material chemical liquid on the wafer surface and in contact with the gaseous protic compound, and thus the protic compound in a short time. It is preferable because it can introduce. At this time, the concentration of the gaseous protic compound in the space is preferably 0.05 to 5% by volume, and more preferably 0.1 to 2% by volume. In addition, 0.1 to 600 seconds are preferable and, as for the contact time, 2 to 180 seconds are more preferable. As a method of spreading the raw material chemical solution on the wafer surface, a known method can be appropriately used, and a spin coating method is particularly preferable.

A water-repellent protective film is formed on the wafer surface by holding the chemical solution prepared as described above on the wafer surface. If necessary, the chemical liquid on the wafer surface may be replaced with a rinse liquid to further perform a rinse treatment.

Then, the liquid is removed from the wafer surface by drying. Since the water-repellent protective film is formed on the wafer surface, it is possible to reduce pattern collapse during drying due to excellent water repellency. In addition, examples of the liquid removed by drying include the chemical liquid for forming a water-repellent protective film, a rinse liquid, or a mixture thereof.

In addition, the surface treatment method of the present invention, before the water-repellent protective film forming step,

(IV) a silazane compound represented by the general formula [4] and

(III) In the raw material chemical solution having an aprotic solvent,

By contacting the acidic compound represented by the general formula [6] in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (III) and (IV),

Having the above (I) to (III), or having the above (I) to (IV),

You may have a chemical liquid preparation step of preparing a chemical liquid for forming a water-repellent protective film in which the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass.

The method of bringing the acidic compound into contact with the raw material chemical is not particularly limited, and a known method can be employed. In addition, when preparing the chemical liquid for forming a water-repellent protective film by contacting, the details are unclear, but the silazane compound represented by the general formula [4] and the acidic compound represented by the general formula [6], as in the following reaction formula By this reaction, an aminosilane compound represented by the general formula [1] and a silicon compound represented by the general formula [2] are produced, and as a result, having the above (I) to (III), or the above (I ) To (IV), and the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass, it is considered that a chemical for forming a water-repellent protective film can be obtained.

[Formula 19]

In addition, when the acidic compound is contacted in a proportion of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (III) and (IV), (I) relative to the total amount of (I) to (III) in the chemical solution for forming a water-repellent protective film It is preferable because it is easy to control the content of 0.02 to 0.5% by mass. The ratio of contacting the acidic compound is more preferably 0.003 to 0.2 mole, particularly preferably 0.003 to 0.1 mole.

As this surface treatment method, surface treatment modes 4 to 5 described later can be employed.

(Surface treatment mode 4)

As shown in Fig. 4, at least, (III) and (IV) are mixed to form a solution (raw chemical liquid), and the acidic compound represented by the general formula [6] is added to the raw chemical liquid (III), (IV). A chemical solution for forming a water-repellent protective film is prepared by contacting at a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of. The acidic compound used for the contact may be diluted with an aprotic solvent (if not in common use, in a dispersed state). Examples of the aprotic solvent used for the dilution include those described as (III) of the present invention.

The raw material chemical liquid and the acidic compound used in the chemical liquid preparation step may be in a liquid state or a gaseous state. For example, a liquid state may be mixed in a container in a chamber, a tank, or a pipe after a confluence point, or a gaseous state may be mixed in a chamber, a vaporization chamber, or a pipe after a confluence point after vaporization. The liquid raw material chemical liquid in the inner container may be exposed to a gaseous acidic compound to be brought into contact.

Then, the obtained chemical liquid is supplied to the wafer surface in a liquid state or a gaseous state, so that the liquid chemical for forming a water-repellent protective film is held on the wafer surface. In addition, since (I) aminosilane is produced by the reaction as described above, a chemical solution in a state in which the content of (I) with respect to the total amount of (I) to (III) is in the range of 0.02 to 0.5% by mass is applied to the wafer surface. To supply. On the other hand, since it is easy to ignore the influence on the composition of the chemical liquid such as side reactions, it is preferable to supply the chemical liquid within 1 day from the contact to the wafer surface, and supply the chemical liquid within 5 hours from the contact to the wafer surface. It is more preferable, and it is particularly preferable to supply the chemical solution within 1 hour from the contact to the wafer surface.

The supply of the chemical liquid is performed while a liquid such as a cleaning liquid or a rinse liquid is held on the wafer surface, and the liquid is replaced with a chemical liquid. At the time of substitution, there is no particular limitation as a liquid such as a cleaning liquid or a rinse liquid held on the wafer surface, but 2-propanol (iPA) or the like is generally used.

By the above substitution, the chemical solution is held on the wafer surface to form a water-repellent protective film on the wafer surface. If necessary, the chemical liquid on the wafer surface may be replaced with a rinse liquid to further perform a rinse treatment.

Then, the liquid is removed from the wafer surface by drying. Since the water-repellent protective film is formed on the wafer surface, it is possible to reduce pattern collapse during drying due to excellent water repellency. In addition, examples of the liquid removed by drying include the chemical liquid for forming a water-repellent protective film, a rinse liquid, or a mixture thereof.

(Surface treatment mode 5)

As shown in Fig. 5, at least, (III) and (IV) are mixed to form a solution (raw chemical liquid), and the raw chemical liquid is supplied to the wafer surface in a liquid state or a gaseous state, so that the wafer surface is in a liquid state. Hold the raw chemical liquid.

The supply of the chemical raw material is performed while a liquid such as a cleaning liquid or a rinse liquid is held on the wafer surface, and the liquid is replaced with the chemical raw material. At the time of substitution, there is no particular limitation as a liquid such as a cleaning liquid or a rinse liquid held on the wafer surface, but 2-propanol (iPA) or the like is generally used.

Next, an acidic compound is brought into contact with the raw material chemical at a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (III) and (IV) to prepare a chemical for forming a water-repellent protective film on the wafer surface. In addition, since (I) aminosilane is produced by the reaction as described above, the chemical solution is held on the wafer surface so that the content of (I) with respect to the total amount of (I) to (III) is in the range of 0.02 to 0.5% by mass. do.

The acidic compound used for the contact may be diluted with an aprotic solvent (if not in common use, in a dispersed state). Examples of the aprotic solvent used for the dilution include those described as (III) of the present invention. The acidic compound used in the chemical solution preparation step may be in a liquid state or a gaseous state. For example, a liquid acidic compound may be added to the liquid raw material chemical liquid held on the wafer surface in the chamber, or the liquid raw material chemical liquid held on the wafer surface in the chamber may be added to the gaseous acidic compound. It may be exposed to contact. In the latter case, for example, a raw material chemical solution may be supplied by placing the inside of the chamber in a vapor atmosphere of an acidic compound having a predetermined concentration.

In addition, when the raw material chemical liquid and the gaseous acidic compound are brought into contact, the contact area can be increased by spreading the liquid raw material chemical liquid on the wafer surface and in contact with the gaseous acidic compound. It is desirable because it can. At this time, the concentration of the gaseous acidic compound in the space is preferably 0.05 to 5% by volume, and more preferably 0.1 to 2% by volume. Further, the contact time is preferably 0.01 to 600 seconds, more preferably 0.1 to 180 seconds. As a method of spreading the raw material chemical solution on the wafer surface, a known method can be appropriately used, and a spin coating method is particularly preferable.

A water-repellent protective film is formed on the wafer surface by holding the chemical solution prepared as described above on the wafer surface. If necessary, the chemical liquid on the wafer surface may be replaced with a rinse liquid to further perform a rinse treatment.

Then, the liquid is removed from the wafer surface by drying. Since the water-repellent protective film is formed on the wafer surface, it is possible to reduce pattern collapse during drying due to excellent water repellency. In addition, examples of the liquid removed by drying include the chemical liquid for forming a water-repellent protective film, a rinse liquid, or a mixture thereof.

Further, as the surface treatment method, a surface treatment mode 6 described later may be employed.

(Surface treatment mode 6)

For example, when pretreatment with SC-1 having an ammonia component is performed, a component (protic compound) containing an NH ₂ group derived from an ammonia component tends to remain on the wafer surface at a molecular level. With respect to the wafer surface in which the component (protic compound) containing the NH ₂ group remained in a predetermined amount at the molecular level, as shown in FIG. 6, at least, obtained by mixing (II), (III), and (IV) A solution (chemical raw material) is supplied in a liquid state or a gaseous state, and the cleaning liquid or the like substituted after the SC-1 or SC-1 treatment is replaced with a liquid raw material chemical. Then, the raw material chemical is brought into contact with a component (protic compound) containing an NH ₂ group remaining in a predetermined amount at the molecular level to prepare the chemical liquid for forming a water repellent protective film according to the present invention on the wafer surface, and the chemical liquid is applied to the wafer. It has a water-repellent protective film formation process and a drying process held on the surface.

Surface treatment mode 3 is preferred from the viewpoint of being easy to suppress the exotherm of the reaction.

As a specific example of the silazane compound represented by the general formula [4], for example, [(CH ₃ ) ₃ Si] ₂ NH, [(CH ₃ ) ₂ Si(H)] ₂ NH, [CH ₃ Si( H) ₂ ] ₂ NH, [C ₂ H ₅ Si(CH ₃ ) ₂ ] ₂ NH, [(C ₂ H ₅ ) ₂ Si(CH ₃ )] ₂ NH, [(C ₂ H ₅ ) ₃ Si] ₂ NH, [C ₃ H ₇ Si(CH ₃ ) ₂ ] ₂ NH, [(C ₃ H ₇ ) ₂ Si(CH ₃ )] ₂ NH, [(C ₃ H ₇ ) ₃ Si] ₂ NH, [C ₄ H ₉ Si(CH ₃ ) ₂ ] ₂ NH, [C ₅ H ₁₁ Si(CH ₃ ) ₂ ] ₂ NH, [C ₆ H ₁₃ Si(CH ₃ ) ₂ ] ₂ NH, [C ₇ H ₁₅ Si(CH ₃ ) ₂ ] ₂ NH, [C ₈ H ₁₇ Si(CH ₃ ) ₂ ] ₂ NH, [C ₉ H ₁₉ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₀ H ₂₁ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₁ H ₂₃ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₂ H ₂₅ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₃ H ₂₇ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₄ H ₂₉ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₅ H ₃₁ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₆ H ₃₃ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₇ H ₃₅ Si(CH ₃ ) ₂ ] ₂ NH, [C ₁₈ H ₃₇ Si(CH ₃ ) ₂ ] ₂ NH, [(C ₂ H ₅ ) ₂ Si(H)] ₂ NH, [C ₂ H ₅ Si(H) ₂ ] ₂ NH, [C ₂ H ₅ Si(CH ₃ )(H)] ₂ NH, [(C ₃ H ₇ ) ₂ Si(H)] ₂ NH, [C ₃ H ₇ Si(H) ₂ ] ₂ NH, [ CF ₃ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH, [C ₂ F ₅ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH, [C ₃ F ₇ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH, [C ₄ F ₉ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH, [C ₅ F ₁₁ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH, [C ₆ F ₁₃ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH, [ C ₇ F ₁₅ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH, [C ₈ F ₁₇ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH, [CF ₃ CH ₂ CH ₂ Si(CH ₃ )( H)] ₂ NH and the like, among others, [(CH ₃ ) ₃ Si] ₂ NH, [C ₂ H ₅ Si(CH ₃ ) ₂ ] ₂ NH, [C ₃ H ₇ Si(CH ₃ ) ₂ ] ₂ NH, [C ₄ H ₉ Si(CH ₃ ) ₂ ] ₂ NH, [CF ₃ CH ₂ CH ₂ Si(CH ₃ ) ₂ ] ₂ NH is preferred, especially [(CH ₃ ) ₃ Si] ₂ NH is preferred.

Specific examples of the acidic compound represented by the general formula [6] include, for example, HCl, HBr, HI, CF ₃ COOH, C ₂ F ₅ COOH, C ₃ F ₇ COOH, C ₄ F ₉ COOH, C ₅ F ₁₁ COOH, C ₆ F ₁₃ COOH, CF ₃ S(=O) ₂ OH, C ₂ F ₅ S(=O) ₂ OH, C ₃ F ₇ S(=O) ₂ OH, C ₄ F ₉ S(= O) ₂ OH, C ₅ F ₁₁ S(=O) ₂ OH, C ₆ F ₁₃ S(=O) ₂ OH, {CF ₃ S(=O) ₂ } ₂ NH, {C ₂ F ₅ S(= O) ₂ } ₂ NH, {C ₃ F ₇ S(=O) ₂ } ₂ NH, {C ₄ F ₉ S(=O) ₂ } ₂ NH, {C ₅ F ₁₁ S(=O) ₂ } ₂ NH, {C ₆ F ₁₃ S(=O) ₂ } ₂ NH, {CF ₃ S(=O) ₂ } ₃ CH, {C ₂ F ₅ S(=O) ₂ } ₃ CH, {C ₃ F ₇ S(=O) ₂ } ₃ CH, {C ₄ F ₉ S(=O) ₂ } ₃ CH, {C ₅ F ₁₁ S(=O) ₂ } ₃ CH, {C ₆ F ₁₃ S(=O) ₂ } ₃ CH and the like are mentioned. Among them, CF ₃ COOH, C ₂ F ₅ COOH, C ₃ F ₇ COOH, and C ₄ F ₉ COOH are preferable, and CF ₃ COOH is particularly preferable.

[Example]

Hereinafter, examples in which the embodiments of the present invention are more specifically disclosed are shown. In addition, the present invention is not limited only to these examples.

Making the surface of the wafer a surface having an uneven pattern, and replacing the cleaning liquid held in at least the concave portion of the uneven pattern with another cleaning liquid is a technique that has been previously established by various studies in other documents, etc., in the present invention, The effect of imparting water repellency when the wafer was surface-treated with the chemical liquid for forming a water-repellent protective film was evaluated. In addition, in Examples, as the liquid to be brought into contact with the wafer surface when evaluating the contact angle, water, which is a typical water-based cleaning solution, was used.

However, in the case of a wafer having an uneven pattern on the surface, the contact angle of the water-repellent protective film itself formed on the surface of the uneven pattern cannot be accurately evaluated.

As for the evaluation of the contact angle of the water droplets, as in JIS R3257 ``Method of testing the wettability of the substrate glass surface,'' several µl of water droplets were dropped on the surface of the sample (substrate), and the angle between the water droplet and the substrate surface was measured. Made by However, in the case of a wafer having a pattern, the contact angle becomes very large. This is because the Wenzel effect or the Cassie effect occurs, and the contact angle is affected by the surface shape (roughness) of the substrate, and the contact angle of the water droplets in appearance increases.

Therefore, in this embodiment, the chemical solution was provided to a wafer having a smooth surface, a protective film was formed on the wafer surface, and the protective film was regarded as a protective film formed on the surface of the wafer having an uneven pattern formed on the surface, and various evaluations were performed. . In addition, in this example, as a wafer having a smooth surface, a "wafer having a 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, a preparation of a chemical liquid for forming a water-repellent protective film or a raw material chemical liquid, a method of surface treatment of a wafer using a chemical liquid for forming a water-repellent protective film, and an evaluation result are described.

[Evaluation method] Evaluation of the contact angle of the protective film formed on the wafer surface (evaluation of the effect of imparting water repellency)

Approximately 2 µl of pure water was placed on the wafer surface on which the protective film was formed, and the angle (contact angle) formed by the water droplet and the wafer surface was measured with a contact angle meter (Kyowa Interfacial Science Co., Ltd.: CA-X type), and 80° or more was determined as a pass .

[Example 1-1]

(1-1) Preparation of a chemical solution for forming a water-repellent protective film

(II) Trimethylsilyltrifluoroacetate (TMS-TFA:(CH ₃ ) ₃ Si-OC(=O)CF ₃ ) as a silicon compound: 15 g, (IV) hexamethyldisilazane as a silazane compound [HMDS: (CH ₃ ) ₃ Si-NH-Si(CH ₃ ) ₃ ]: 70 g, (III) propylene glycol monomethyl ether acetate (PGMEA): 915 g, which is an aprotic solvent, was mixed to obtain a raw material chemical solution in a solution state. Next, by adding 3.6 g of water as a protic compound to the raw material chemical solution, 0.2 mol of the protic compound (liquid water) per 1 kg of the total amount of TMS-TFA, HMDS, and PGMEA is brought into contact with the raw material chemical solution. A chemical solution for forming a protective film was prepared.

(1-2) cleaning of silicon wafers

A silicon wafer having a smooth thermal oxide film (Si wafer having a thermal oxide layer having a thickness of 1 μm on the surface) was immersed in 1% by mass aqueous hydrofluoric acid solution at room temperature for 10 minutes, and then in pure water for 1 minute at room temperature, 2-propanol (iPA ) At room temperature for 1 minute.

(1-3) Surface treatment with chemical solution for forming protective film on the surface of silicon wafer

The cleaned silicon wafer was immersed in the chemical solution for forming a water-repellent protective film prepared in "(1-1) Preparation of a chemical liquid for forming a water-repellent protective film" at 25°C for 30 seconds, and immersed in iPA for 30 seconds at room temperature. Finally, the silicon wafer was taken out from the iPA, air was blown, and the iPA on the surface was removed and dried.

In this example, the surface treatment was performed by the method of surface treatment mode 2. When the obtained wafer was evaluated, as shown in Table 1, when the initial contact angle before the surface treatment was less than 10°, the contact angle after the surface treatment was 90°, showing an excellent effect of imparting water repellency.

[Table 1]

[Examples 1-2 to 1-23]

The surface of the wafer as in Example 1-1 except for changing the type, contact method, or contact amount of the protic compound used in Example 1-1, and the type or content of the aminosilane compound, silicon compound, or silazane compound. The process was performed, and the evaluation was further performed. Table 1 shows the results.

In addition, in the table, "iPA" refers to 2-propanol, "MeOH" refers to methanol, "EtOH" refers to ethanol, "nBuOH" refers to 1-butanol, and "PGME" refers to propylene. It means glycol monomethyl ether, and "TFAcA" means trifluoroacetamide.

In addition, in Example 1-18, first, dibutyltetramethyldisilazane (DBTMDS:C ₄ H ₉ (CH ₃ ) ₂ Si-NH-Si(CH ₃ ) ₂ C ₄ H ₉ ) which is a silazane compound. :86g, PGMEA:900g which is an aprotic solvent, and trifluoroacetic anhydride:14g were mixed, and the raw material chemical liquid in a solution state was obtained by the reaction mentioned later. Trifluoroacetic anhydride reacts directly with DBTMDS, and butyldimethylsilyltrifluoroacetate [BDMS-TFA:C ₄ H ₉ (CH ₃ ) ₂ Si-OC (=O) CF ₃ ] and butyldimethylsilyl trifluoro Roacetamide [BDS-TFAcA:C ₄ H ₉ (CH ₃ ) ₂ Si-NH-C(=O)CF ₃ ]. That is, the raw material chemical solution of the present example differs in the type of the silicon compound and the silazane compound, and contains BDS-TFAcA as another silicon compound.

Next, by adding 0.9 g of water, which is a protic compound, to the raw material chemical, 0.05 mol of the protic compound (liquid water) per 1 kg of the total amount of BDMS-TFA, DBTMDS, and PGMEA is brought into contact with the raw material chemical, A chemical solution for forming a protective film was prepared.

In addition, in Example 1-19, first, dioctyltetramethyldisilazane (DOTMDS:C ₈ H ₁₇ (CH ₃ ) ₂ Si-NH-Si(CH ₃ ) ₂ C ₈ H ₁₇ ) which is a silazane compound. : 89 g, PGMEA as an aprotic solvent: 900 g, and trifluoroacetic anhydride: 11 g were mixed, and a raw material chemical solution in a solution state was obtained by a reaction described below. Trifluoroacetic anhydride reacts directly with DOTMDS, and octyldimethylsilyltrifluoroacetate [ODMS-TFA:C ₈ H ₁₇ (CH ₃ ) ₂ Si-OC (=O) CF ₃ ] and octyldimethylsilyl trifluoro Roacetamide [ODS-TFAcA:C ₈ H ₁₇ (CH ₃ ) ₂ Si-NH-C(=O)CF ₃ ]. That is, the raw material chemical solution of the present example differs in the type of the silicon compound and the silazane compound, and contains ODS-TFAcA as another silicon compound.

Next, by adding 0.9 g of water as a protic compound to the raw material chemical solution, 0.05 mol of the protic compound (liquid water) per 1 kg of the total amount of ODMS-TFA, DOTMDS, and PGMEA is brought into contact with the raw material chemical solution. A chemical solution for forming a protective film was prepared.

In addition, in Example 1-22, first, a silazane compound HMDS: 83 g, an aprotic solvent PGMEA: 900 g, trifluoroacetic anhydride: 17 g were mixed, and a raw material chemical solution in a solution state by a reaction described below. Got it. Trifluoroacetic anhydride reacts directly with HMDS to change to TMS-TFA and trimethylsilyltrifluoroacetamide [TMS-TFAcA:(CH ₃ ) ₃ Si-NH-C(=O)CF ₃ ]. That is, the raw material chemical solution of this example contains TMS-TFAcA as other silicon compounds other than the silicon compound and silazane compound.

In addition, in Examples 1-20, 1-21, and 1-23, the concentration of the protonic compound is in a space controlled in advance so that the ratio of the total amount of (II), (III), and (IV) is less than 0.001 mole per 1 kg. A raw material chemical solution was placed, a predetermined amount of a gaseous protonic compound was introduced into the space, and the chemical solution for forming a water-repellent protective film was prepared by bringing both of them into contact.

In any of the Examples, the initial contact angle before the surface treatment was less than 10°, and the contact angle after the surface treatment was 80° or more, thereby exhibiting an excellent water repellency imparting effect.

[Comparative Examples 1-1 to 1-3]

The wafer was surface-treated in the same manner as in Example 1-1, except that the type and contact amount of the protic compound used in Example 1-1 was changed, and further evaluated. Table 1 shows the results. In both cases, the contact angle after the surface treatment was less than 80°, and the effect of imparting water repellency was inferior to that of the examples.

From the results of Examples 1-1 to 1-3 and Comparative Examples 1-1 and 1-2, a plot of the contact angle after surface treatment with respect to the contact amount of the protic compound (liquid water) is shown in FIG. A plot of the contact angle after surface treatment with respect to the content of the (I) aminosilane compound (TMS-NH ₂ ) in the total amount of) to (III) is shown in Fig. 8, respectively.

From Figs. 7 and 8, in Comparative Example 1-1 in which the protic compound (liquid water) is not brought into contact, and in Comparative Example 1-2 with too much contact amount, (I) in the total amount of (I) to (III) ) Since the content of all aminosilane compounds (TMS-NH ₂ ) is too small (the content of (I) relative to the total amount of (I) to (III) is out of the range of 0.02 to 0.5 mass%), the contact angle after surface treatment Was less than 80°.

In contrast, Example 1 using a chemical solution for forming a water-repellent protective film having a content of (I) of 0.02 to 0.5% by mass relative to the total amount of (I) to (III) by contacting a protic compound (liquid water). In all of 1 to 1-3, the contact angle after surface treatment exceeded 80 degrees, and showed the effect of providing more excellent water repellency.

In addition, the same tendency was confirmed even when the type of the protic compound was changed.

From the results of Examples 1-4 to 1-6 and Comparative Examples 1-1 and 1-3, a plot of the contact angle after surface treatment with respect to the contact amount of the protic compound (iPA in a liquid state) is shown in Fig. 9, (I A plot of the contact angle after surface treatment with respect to the content of the (I) aminosilane compound (TMS-NH ₂ ) in the total amount of) to (III) is shown in Fig. 10, respectively.

9 and 10, in Comparative Example 1-1 in which the protic compound (iPA in liquid state) was not brought into contact, and Comparative Example 1-3 in which the contact amount was too large, (I) in the total amount of (I) to (III) ) Since the content of all aminosilane compounds (TMS-NH ₂ ) is too small (the content of (I) relative to the total amount of (I) to (III) is out of the range of 0.02 to 0.5 mass%), the contact angle after surface treatment Was less than 80°.

In contrast, Example 1 using a chemical for forming a water-repellent protective film having a content of (I) of 0.02 to 0.5% by mass relative to the total amount of (I) to (III) by contacting a protic compound (iPA in a liquid state). In all of 4 to 1-6, the contact angle after surface treatment exceeded 80 degrees, and showed a more excellent water repellency imparting effect.

[Example 2-1]

(2-1) Preparation of raw material chemical solution

(II) TMS-TFA as a silicon compound: 15 g, (IV) HMDS as a silazane compound: 70 g, and (III) PGMEA: 915 g as an aprotic solvent were mixed to obtain a raw material chemical solution in a solution state.

(2-2) Preparation of a chemical liquid for forming a water-repellent protective film and surface treatment with a chemical liquid for forming a protective film on the surface of a silicon wafer

The silicon wafer cleaned in the same manner as in Example 1-1 was immersed in the raw material chemical solution prepared in the above "(2-1) Preparation of the raw material chemical solution", and then liquid water as a protic compound: 3.6 g was obtained. By adding to the raw material chemical, 0.2 mol of a protic compound (liquid water) was brought into contact with the raw material chemical with respect to 1 kg of the total amount of TMS-TFA, HMDS, and PGMEA to prepare a chemical for forming a water-repellent protective film. After immersion in the water-repellent protective film-forming chemical solution for 30 seconds, the silicon wafer was taken out and immersed in iPA for 30 seconds at room temperature, then the silicon wafer was taken out from the iPA, air was sprayed, and the iPA on the surface was removed and dried.

In this example, the surface treatment was performed by the method of surface treatment mode 3. When the obtained wafer was evaluated, as shown in Table 2, when the initial contact angle before the surface treatment was less than 10°, the contact angle after the surface treatment was 90°, showing an excellent effect of imparting water repellency.

[Table 2]

[Examples 2-2 to 2-16]

The surface of the wafer as in Example 2-1, except that the type, contact method, and contact amount of the protic compound used in Example 2-1, and the type or content of the aminosilane compound, silicon compound, or silazane compound were changed. The process was performed, and the evaluation was further performed. The results are shown in Table 2.

In addition, in Examples 2-13, 2-14, and 2-16, the silicon wafer cleaned in the same manner as in Example 1-1 was placed in a space into which a predetermined amount of a gaseous protic compound was introduced. , By immersing the raw material chemical liquid on the silicon wafer surface (SiO ₂ film side surface), the raw material chemical liquid and the protonic compound were brought into contact to prepare a chemical liquid for forming a water-repellent protective film.

In any of the Examples, the initial contact angle before the surface treatment was less than 10°, and the contact angle after the surface treatment was 80° or more, thereby exhibiting an excellent water repellency imparting effect.

[Comparative Examples 2-1 to 2-3]

The wafer was surface-treated in the same manner as in Example 2-1, except that the type and contact amount of the protic compound used in Example 2-1 were changed, and further evaluated. The results are shown in Table 2. In both cases, the contact angle after the surface treatment was less than 80°, and the effect of imparting water repellency was inferior to that of the examples.

[Example 3-1]

(IV) HMDS as a silazane compound: 71 g and (III) PGMEA: 929 g as an aprotic solvent were mixed to obtain a raw material chemical solution in a solution state. Next, by adding 22.8 g of the acidic compound trifluoroacetic acid [TFA:CF ₃ COOH]: to the raw material chemical, 0.2 mol of the acidic compound (liquid TFA) per 1 kg of the total amount of HMDS and PGMEA is added to the raw material chemical. It was brought into contact to prepare a chemical liquid for forming a water-repellent protective film. Other than that, surface treatment of the wafer was performed in the same manner as in Example 1-1, and the evaluation was further performed. Table 3 shows the results.

In this example, the surface treatment was performed by the method of surface treatment mode 4. When the obtained wafer was evaluated, as shown in Table 3, when the initial contact angle before the surface treatment was less than 10°, the contact angle after the surface treatment was 90°, and an excellent water repellency imparting effect was exhibited.

[Table 3]

[Examples 3-2 to 3-6]

The wafer was surface-treated in the same manner as in Example 3-1, except that the type and contact amount of the acidic compound used in Example 3-1, and the type or content of the aminosilane compound, silicon compound, or silazane compound were changed, Further, the evaluation was made. Table 3 shows the results.

In addition, in the table, "TFMSA" refers to trifluoromethanesulfonic acid [CF ₃ SO ₃ H], and "TMS-TFMSA" refers to trimethylsilyltrifluoromethanesulfonate [(CH ₃ ) ₃ Si-OS (= O) means ₂ CF ₃ ].

In any of the Examples, the initial contact angle before the surface treatment was less than 10°, and the contact angle after the surface treatment was 80° or more, thereby exhibiting an excellent water repellency imparting effect.

[Comparative Examples 3-1, 3-2]

The wafer was surface-treated in the same manner as in Example 3-1, except that the contact amount of the acidic compound used in Example 3-1 was changed, and the evaluation was further performed. Table 3 shows the results. In both cases, the contact angle after the surface treatment was less than 80°, and the effect of imparting water repellency was inferior to that of the examples.

[Example 4-1]

(4-1) Preparation of raw material chemical solution

(IV) HMDS as a silazane compound: 71 g and (III) PGMEA: 929 g as an aprotic solvent were mixed to obtain a raw material chemical solution in a solution state.

(4-2) Preparation of a chemical liquid for forming a water-repellent protective film and surface treatment with a chemical liquid for forming a protective film on the surface of a silicon wafer

The silicon wafer cleaned in the same manner as in Example 1-1 was immersed in the raw material chemical solution prepared in the above "(4-1) Preparation of the raw material chemical solution", and then, 22.8 g of TFA in a liquid state as an acidic compound was added to the raw material. By adding to the chemical solution, 0.2 mol of an acidic compound (liquid TFA) per 1 kg of the total amount of HMDS and PGMEA was brought into contact with the raw material chemical to prepare a chemical for forming a water-repellent protective film. After immersion in the water-repellent protective film-forming chemical solution for 30 seconds, the silicon wafer was taken out and immersed in iPA for 30 seconds at room temperature, then the silicon wafer was taken out from the iPA, air was sprayed, and the iPA on the surface was removed and dried.

In this example, the surface treatment was performed by the method of the surface treatment aspect 5. When the obtained wafer was evaluated, as shown in Table 4, when the initial contact angle before the surface treatment was less than 10°, the contact angle after the surface treatment was 90°, showing an excellent effect of imparting water repellency.

[Table 4]

[Examples 4-2 to 4-6]

The wafer was surface-treated in the same manner as in Example 4-1, except that the type and contact amount of the acidic compound used in Example 4-1, and the type or content of the aminosilane compound, silicon compound, or silazane compound were changed, Further, the evaluation was made. The results are shown in Table 4.

In any of the Examples, the initial contact angle before the surface treatment was less than 10°, and the contact angle after the surface treatment was 80° or more, thereby exhibiting an excellent water repellency imparting effect.

[Comparative Examples 4-1, 4-2]

Except having changed the contact amount of the acidic compound used in Example 4-1, the surface treatment of a wafer was performed like Example 4-1, and the evaluation was performed further. The results are shown in Table 4. In both cases, the contact angle after the surface treatment was less than 80°, and the effect of imparting water repellency was inferior to that of the examples.

As described above, even in different surface treatment modes, the effect of imparting water repellency can be further improved compared to the prior art by employing the chemical liquid for forming a water-repellent protective film according to the present invention and the wafer surface treatment method according to the present invention.

[Example 1-1a]

In ``Preparation of a chemical liquid for forming a water repellent protective film'', except that water, which is a protic compound, is diluted in PGMEA, which is an aprotic solvent (if not commonly used, in a dispersed state), except for adding it to the raw material chemical liquid. The same operation as in Example 1-1 was performed, and the same evaluation was performed. In addition, the amount of water added was 0.2 mol with respect to 1 kg of the total amount of TMS-TFA, HMDS, PGMEA contained in the raw material chemical solution, and PGMEA used for dilution. Table 5 shows the results. In addition, the amount of PGMEA used for dilution and the amount of PGMEA contained in the raw material chemical were made the same amount.

[Table 5]

[Examples 1-2a to 1-22a, Comparative Examples 1-2a to 1-3a]

The surface of the wafer as in Example 1-1a except for changing the type, contact method, and contact amount of the protic compound used in Example 1-1a, and the type or content of the aminosilane compound, silicon compound, or silazane compound. The process was performed, and the evaluation was further performed. In addition, in Examples 1-20a and 1-21a, a protic compound in a gaseous state was diluted in a gaseous aprotic solvent and brought into contact with a raw material chemical. Table 5 shows the results.

In addition, the results of Comparative Example 1-1 were described for Comparative Examples in which the protic compound was not brought into contact.

[Example 2-1a]

In ``Preparation of a chemical liquid for forming a water repellent protective film and surface treatment with a chemical liquid for forming a protective film on the surface of a silicon wafer'', water as a protic compound is diluted in PGMEA as an aprotic solvent (dispersion if not commonly used). In the same state), except for adding to the raw material chemical liquid, the same operation as in Example 2-1 was performed, and the same evaluation was performed. In addition, the amount of water added was 0.2 mol with respect to 1 kg of the total amount of TMS-TFA, HMDS, PGMEA contained in the raw material chemical solution, and PGMEA used for dilution. Table 6 shows the results. In addition, the amount of PGMEA used for dilution and the amount of PGMEA contained in the raw material chemical were made to be the same amount.

[Table 6]

[Examples 2-2a to 2-15a, Comparative Examples 2-2a to 2-3a]

The surface of the wafer as in Example 2-1a except that the type, contact method, and contact amount of the protic compound used in Example 2-1a, and the type or content of the aminosilane compound, silicon compound, or silazane compound were changed. The process was performed, and the evaluation was further performed. In addition, in Examples 2-13a and 2-14a, the protic compound in the gaseous state was diluted with an aprotic solvent in the gaseous state to contact the raw material chemical solution. Table 6 shows the results.

In addition, the results of Comparative Example 2-1 were described with respect to Comparative Examples in which the protic compound was not brought into contact.

[Example 3-1a]

In the ``Preparation of a chemical liquid for forming a water-repellent protective film'', examples except that TFA, an acidic compound, is diluted in PGMEA, an aprotic solvent (if not commonly used, dispersed), and added to the raw material chemical liquid. The same operation as in 3-1 was performed, and the same evaluation was performed. In addition, the amount of TFA added was 0.2 mol with respect to 1 kg of the total amount of HMDS, PGMEA contained in the raw material chemical solution, and PGMEA used for dilution. Table 7 shows the results. In addition, the amount of PGMEA used for dilution and the amount of PGMEA contained in the raw material chemical were made the same amount.

[Table 7]

[Examples 3-2a to 3-6a, Comparative Example 3-2a]

Wafer surface treatment was performed in the same manner as in Example 3-1a except that the type and contact amount of the acidic compound used in Example 3-1a, and the type or content of the aminosilane compound, silicon compound, or silazane compound were changed, Further, the evaluation was made. Table 7 shows the results.

In addition, the results of Comparative Example 3-1 were described with respect to Comparative Examples in which the acidic compound was not brought into contact.

[Example 4-1a]

In ``Preparation of a chemical for forming a water-repellent protective film and surface treatment with a chemical for forming a protective film on the surface of a silicon wafer'', TFA, an acidic compound, is diluted in PGMEA, an aprotic solvent (if not used, it is dispersed. In the state), except for adding to the raw material chemical liquid, the same operation as in Example 4-1 was performed, and the same evaluation was performed. In addition, the amount of TFA added was 0.2 mol with respect to 1 kg of the total amount of HMDS, PGMEA contained in the raw material chemical solution, and PGMEA used for dilution. The results are shown in Table 8. In addition, the amount of PGMEA used for dilution and the amount of PGMEA contained in the raw material chemical were made to be the same amount.

[Table 8]

[Examples 4-2a to 4-6a, Comparative Example 4-2a]

Wafer surface treatment was performed in the same manner as in Example 4-1a except that the type and contact amount of the acidic compound used in Example 4-1a, and the type or content of the aminosilane compound, silicon compound, or silazane compound were changed, Further, the evaluation was made. The results are shown in Table 8.

In addition, the result of Comparative Example 4-1 was described about the comparative example in which the acidic compound was not brought into contact.

[Example 5-1]

In ``Preparation of a chemical liquid for forming a water-repellent protective film'', the same as in Example 1-2 except that the protic compound is NH ₃ and diluted in dioxane as an aprotic solvent, and added to the raw material chemical liquid. Operation was performed and the same evaluation was performed. In addition, the amount of NH ₃ added was 0.05 mol with respect to 1 kg of the total amount of TMS-TFA, HMDS, PGMEA contained in the raw material chemical solution, and dioxane used for dilution. The results are shown in Table 9. In addition, the concentration of the NH ₃ /dioxane solution when added to the raw material chemical solution was set to 0.4 mol/liter.

[Table 9]

[Example 5-2]

The wafer was surface-treated in the same manner as in Example 5-1, except that the type of the aprotic solvent used for dilution in Example 5-1 was changed to tetrahydrofuran [THF], and further evaluated. The results are shown in Table 9.

In addition, the results of Comparative Example 1-1 were described for Comparative Examples in which the protic compound was not brought into contact.

[Example 6-1]

In ``Preparation of a chemical for forming a water-repellent protective film and surface treatment with a chemical for forming a protective film on the surface of a silicon wafer'', a raw material chemical solution in a state in which the protonic compound is NH ₃ and diluted in dioxane as an aprotic solvent. Except for adding to, the same operation as in Example 2-2 was performed, and the same evaluation was performed. In addition, the amount of NH ₃ added was 0.05 mol with respect to 1 kg of the total amount of TMS-TFA, HMDS, PGMEA contained in the raw material chemical solution, and dioxane used for dilution. Table 10 shows the results. In addition, the concentration of the NH ₃ /dioxane solution when added to the raw material chemical solution was set to 0.4 mol/liter.

[Table 10]

[Example 6-2]

The wafer was surface-treated in the same manner as in Example 6-1, except that the type of the aprotic solvent used for dilution in Example 6-1 was changed to tetrahydrofuran [THF], and further evaluated. Table 10 shows the results.

In addition, the results of Comparative Example 2-1 were described with respect to Comparative Examples in which the protic compound was not brought into contact.

As described above, even in a state in which the protic compound or acidic compound added to the raw material chemical solution is diluted in an aprotic solvent (if not commonly used, it is dispersed), the effect of imparting water repellency can be further improved compared to the conventional one. .

Claims (19)

(I) an aminosilane compound represented by the following general formula [1] and
(II) a silicon compound represented by the following general formula [2] and
(III) has an aprotic solvent,
A chemical liquid for forming a water-repellent protective film, wherein the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass.
[Formula 20]

[In formula [1], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. a is an integer of 1 to 3, b is an integer of 0 to 2, and the sum of a and b is 1 to 3.]
[Formula 21]

[In formula [2], R ² is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. In addition, X is a halogen group, -OC(=O)R ³ , -OS(=O) ₂ -R ³ , -N(S(=O) ₂ -R ³ ) ₂ , -C(S(=O ) ₂ -R ³ ) represents at least one group selected from the group consisting of ₃ . R ³ is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c and d is 1 to 3.] The method of claim 1,
The chemical liquid for forming a water-repellent protective film, wherein (I) is a compound represented by the following general formula [3].
[Formula 22]

[In formula [3], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.] The method according to claim 1 or 2,
(IV) A chemical for forming a water-repellent protective film further containing a silazane compound represented by the following general formula [4].
[Formula 23]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.] The method according to any one of claims 1 to 3,
The chemical liquid for forming a water-repellent protective film, wherein the content of (II) relative to the total amount of the above (I) to (III) is 0.05 to 20% by mass. The method according to any one of claims 1 to 4,
The chemical liquid for forming a water-repellent protective film, wherein (II) is at least one compound selected from the group consisting of the following general formula [5].
[Formula 24]

[In formula [5], R ² is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element, and R ³ Silver is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms. In addition, g is an integer of 1 to 3.] A water-repellent protective film forming step in which at least one liquid selected from the group consisting of a cleaning liquid and a rinse liquid is held on the wafer surface, the liquid is replaced with a chemical for forming a water-repellent protective film, and the chemical is held on the wafer surface, and , As a method for surface treatment of a wafer having a drying process,
The chemical solution for forming a water-repellent protective film,
(I) an aminosilane compound represented by the following general formula [1] and
(II) a silicon compound represented by the following general formula [2] and
(III) has an aprotic solvent,
A method for surface treatment of a wafer, wherein the content of (I) relative to the total amount of (I) to (III) is 0.02 to 0.5% by mass.
[Formula 25]

[In formula [1], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. a is an integer of 1 to 3, b is an integer of 0 to 2, and the sum of a and b is 1 to 3.]
[Formula 26]

[In formula [2], R ² is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. In addition, X is a halogen group, -OC(=O)R ³ , -OS(=O) ₂ -R ³ , -N(S(=O) ₂ -R ³ ) ₂ , -C(S(=O) ₂ -R ³ ) represents at least one group selected from the group consisting of ₃ . R ³ is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms, c is an integer of 1 to 3, d is an integer of 0 to 2, and the sum of c and d is 1 to 3.] The method of claim 6,
The surface treatment method of a wafer, wherein (I) is a compound represented by the following general formula [3].
[Formula 27]

[In formula [3], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.] The method according to claim 6 or 7,
The method for surface treatment of a wafer, wherein the chemical liquid for forming a water-repellent protective film further contains (IV) a silazane compound represented by the following general formula [4].
[Formula 28]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.] The method according to any one of claims 6 to 8,
Before the process of forming the water repellent protective film,
(II) a silicon compound represented by the general formula [2] and
(IV) a silazane compound represented by the following general formula [4] and
(III) In the raw material chemical solution having an aprotic solvent,
By contacting the protic compound in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (II), (III) and (IV),
Having the above (I) to (III), and having a chemical solution preparation step of preparing a chemical solution for forming a water-repellent protective film, wherein the content of (I) is 0.02 to 0.5% by mass relative to the total amount of (I) to (III), Wafer surface treatment method.
[Chemical Formula 29]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.] The method of claim 8,
Before the process of forming the water repellent protective film,
(II) a silicon compound represented by the general formula [2] and
(IV) a silazane compound represented by the following general formula [4] and
(III) In the raw material chemical solution having an aprotic solvent,
By contacting the protic compound in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (II), (III) and (IV),
Having the above (I) to (IV) and having a chemical solution preparation step of preparing a chemical solution for forming a water-repellent protective film, wherein the content of (I) is 0.02 to 0.5% by mass relative to the total amount of (I) to (III), Wafer surface treatment method.
[Formula 30]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.] The method of claim 9 or 10,
The method for surface treatment of a wafer, wherein the chemical solution preparation step is to introduce the raw material chemical solution into a space containing a protic compound and bring both of them into contact. The method according to any one of claims 9 to 11,
The method for surface treatment of a wafer, wherein the protic compound is in a gaseous state. The method according to any one of claims 9 to 11,
The method for surface treatment of a wafer, wherein the protic compound is in a liquid state. The method according to any one of claims 9 to 13,
The method for surface treatment of a wafer, wherein the protic compound is a compound having an -OH group and/or a -NH ₂ group. The method according to any one of claims 9 to 14,
The method for surface treatment of a wafer, wherein the protic compound is water and/or 2-propanol. The method according to any one of claims 6 to 8,
Before the process of forming the water repellent protective film,
(IV) a silazane compound represented by the following general formula [4] and
(III) In the raw material chemical solution having an aprotic solvent,
By contacting an acidic compound represented by the following general formula [6] in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (III) and (IV),
Having the above (I) to (III), and having a chemical solution preparation step of preparing a chemical solution for forming a water-repellent protective film, wherein the content of (I) is 0.02 to 0.5% by mass relative to the total amount of (I) to (III), Wafer surface treatment method.
[Formula 31]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]
[Formula 32]

[In formula [6], X is a halogen group, -OC(=O)R ³ , -OS(=O) ₂ -R ³ , -N(S(=O) ₂ -R ³ ) ₂ , -C (S(=O) ₂ -R ³ ) ₃ is shown. R ³ is a C 1 to C 6 monovalent perfluoroalkyl group.] The method of claim 8,
Before the process of forming the water repellent protective film,
(IV) a silazane compound represented by the following general formula [4] and
(III) In the raw material chemical solution having an aprotic solvent,
By contacting an acidic compound represented by the following general formula [6] in a ratio of 0.001 to 0.3 mol with respect to 1 kg of the total amount of (III) and (IV),
Having the above (I) to (IV) and having a chemical solution preparation step of preparing a chemical solution for forming a water-repellent protective film, wherein the content of (I) is 0.02 to 0.5% by mass relative to the total amount of (I) to (III), Wafer surface treatment method.
[Formula 33]

[In formula [4], R ¹ is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element. e is an integer of 1 to 3, f is an integer of 0 to 2, and the sum of e and f is 3.]
[Formula 34]

[In formula [6], X is a halogen group, -OC(=O)R ³ , -OS(=O) ₂ -R ³ , -N(S(=O) ₂ -R ³ ) ₂ , -C (S(=O) ₂ -R ³ ) ₃ is shown. R ³ is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms.] The method according to any one of claims 6 to 17,
The method for surface treatment of a wafer, wherein the content of (II) relative to the total amount of the (I) to (III) is 0.05 to 20% by mass. The method according to any one of claims 6 to 18,
The method for surface treatment of a wafer, wherein (II) is at least one compound selected from the group consisting of the following general formula [5].
[Formula 35]

[In formula [5], R ² is each independently a monovalent organic group containing a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with a fluorine element, and R ³ Silver is a monovalent perfluoroalkyl group having 1 to 6 carbon atoms. In addition, g is an integer of 1 to 3.]

Images