JP2013118347A - Cleaning method of wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning method to improve a cleaning step easily inducing pattern collapse in a manufacturing method of a wafer having an uneven pattern on the surface.SOLUTION: A cleaning method of a wafer having an uneven pattern on the surface comprises at least the steps of: cleaning the wafer with a cleaning liquid; replacing the cleaning liquid kept in a recess part of the wafer after cleaning with a water-repellent chemical liquid; and drying the wafer, where the cleaning liquid comprises 80 mass% or more of a solvent having a boiling-point of 55 to 200°C, and in the replacing step, the temperature of the water-repellent chemical liquid is 40°C or more and below the boiling-point of the water-repellent chemical liquid, for water-repelling of at least the recess part surface.

Description

  The present invention relates to a substrate (wafer) cleaning technique in manufacturing a semiconductor device or the like.

  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 accordingly, the particle size that causes a reduction in manufacturing yield is also miniaturized. As a result, a cleaning process intended to remove contaminants such as micronized particles is frequently used, and as a result, the cleaning process accounts for 30 to 40% of the entire semiconductor manufacturing process.

  On the other hand, in the conventional cleaning with the mixed ammonia cleaning agent, the damage to the wafer due to the basicity becomes a problem as the circuit pattern is miniaturized. For this reason, replacement with, for example, a dilute hydrofluoric acid-based cleaning agent with less damage is in progress.

  Thus, although the problem of damage to the wafer due to cleaning has been improved, the problem due to the increase in the aspect ratio of the pattern accompanying the miniaturization of the semiconductor device has become apparent. That is, after cleaning or rinsing, a phenomenon that the pattern collapses when the gas-liquid interface passes through the pattern causes a significant decrease in yield.

  Patent Document 1 discloses a technique for replacing the cleaning liquid from water to 2-propanol before the gas-liquid interface passes through the pattern as a technique for suppressing pattern collapse. However, it is said that there is a limit such that the aspect ratio of the pattern that can be handled is 5 or less.

  Further, Patent Document 2 discloses a technique for a resist pattern as a technique for suppressing pattern collapse. This technique is a technique for suppressing pattern collapse by reducing the capillary force to the limit. However, since the disclosed technique is intended for a resist pattern, it modifies the resist itself, and can be finally removed together with the resist. Therefore, it is necessary to assume a method for removing the treatment agent after drying. Is not applicable to this purpose.

In addition, as a technique for preventing pattern collapse of a semiconductor device, use of a critical fluid, use of liquid nitrogen, or the like has been proposed. In US Pat. No. 6,057,033, microelectronics having a hardened photoresist, post-etch residue and / or underlayer anti-reflective coating (BARC) and a hardened photoresist, post-etch residue and / or underlayer anti-reflective coating (BARC) thereon. A method of removing from a device, sufficient to remove the cured photoresist, post-etch residue and / or BARC from the microelectronic device having the photoresist, residue and / or BARC thereon. Contacting the microelectronic device with a concentrated fluid concentrate under time and sufficient contact conditions, said concentrated fluid concentrate comprising at least one co-solvent and optionally at least one oxidant / radical source. , Optionally at least one interface And sex agent, and at least one silicon-containing layer passivating agent optionally, wherein the concentrate comprises the following components (I) or (II):
Disclosed is a method further comprising (I) at least one fluoride source and optionally at least one acid, and (II) at least one of at least one acid. However, a special cleaning device is required as compared with the conventional cleaning process, and it is difficult to apply to a mass production process due to poor throughput.

  In Patent Documents 4 and 5, a wafer surface on which a concavo-convex pattern is formed by a film containing silicon is surface-modified by oxidation or the like, and a water-repellent coating is formed on the surface using a water-soluble surfactant or silane coupling agent. A cleaning method is disclosed that forms and reduces capillary forces and prevents pattern collapse.

  Patent Documents 6 and 7 include a step of treating the surface of a resin pattern provided on a substrate or a pattern to be etched formed on a substrate by etching with a surface treatment liquid containing a silylating agent and a solvent; A surface treatment method including a step of cleaning a resin pattern or a pattern to be etched after treatment with a treatment liquid is disclosed.

  Patent Document 8 discloses a step of forming a semiconductor device having a substrate and a dielectric layer having a structure protruding from the substrate, a step of cleaning the structure of the semiconductor device with an aqueous solution, and after the cleaning, A step of substituting with one liquid, and a step of treating the structure with a second liquid containing a hydrophobic treatment agent that reacts with the side wall of the protruding structure and forms a hydrophobic layer on the side wall surface after the substitution. A cleaning method is disclosed.

Patent Document 9 discloses a cleaning agent for silicon wafers having a fine uneven pattern on the surface. The cleaning agent includes a cleaning liquid A and a cleaning liquid B. The cleaning liquid A is an aqueous solution, and the cleaning liquid B has an uneven pattern. The cleaning liquid B is used to make the recess water-repellent, and the cleaning liquid B is an alcohol solution containing a hydrolyzable portion that generates a unit that can be chemically bonded to the silicon element of the silicon wafer, a water-repellent compound containing a hydrophobic group, and an alcohol solvent. And a water-repellent cleaning liquid obtained by mixing the water-repellent compound in an amount of 0.2 to 20% by mass in 100% by mass of the total amount of the cleaning liquid B, and water or an acidic aqueous solution. As a result, the capillary force when assuming that water is retained in the recesses on the surface of the silicon wafer that has been made water-repellent by the cleaning liquid B is 2.1 MN / m ² or less. A method of cleaning the surface of a silicon wafer using a cleaning agent for a recon wafer is disclosed.

Patent Document 10 discloses a silicon wafer cleaning agent having a fine uneven pattern on the surface, and the silicon wafer cleaning agent is used to repel water at least in the aqueous cleaning liquid and at least the recesses of the uneven pattern during the cleaning process. A water-repellent cleaning solution, the water-repellent cleaning solution comprising a water-repellent compound containing a reactive site capable of chemically bonding to silicon element of a silicon wafer and a hydrophobic group, or a total amount of the water-repellent cleaning solution 100 By containing 0.1% by mass or more of the water repellent compound and an organic solvent with respect to mass%, water is formed in the recesses on the surface of the silicon wafer that has been made water repellent by the water repellent cleaning liquid. Disclosed is a method for cleaning a silicon wafer surface using a silicon wafer cleaning agent that has a capillary force of 2.1 MN / m ² or less assuming that Yes.

Patent Document 11 discloses a silicon wafer cleaning agent having a fine concavo-convex pattern on the surface. The silicon wafer cleaning agent is used to repel water at least in a water-based cleaning solution and at least a concave portion of the concavo-convex pattern during the cleaning process. A water-repellent cleaning liquid, and the water-repellent cleaning liquid is a mixture of a water-repellent compound containing a reactive site chemically bonded to silicon element of a silicon wafer and a hydrophobic group, and an organic solvent containing a nitrogen-containing compound solvent. The water-repellent compound is mixed and contained so that the total amount of the water-repellent cleaning liquid is 100% by weight, and further includes the nitrogen-containing compound solvent. 1. Assuming that the element bonded to nitrogen is carbon, the capillary force when assuming that water is retained in the recesses on the surface of the silicon wafer that has been made water-repellent by the water-repellent cleaning liquid is 2. Using MN / m ² or less and allowed to those detergent silicon wafer is, cleaning method of silicon wafer surface is disclosed.

  Patent Document 12 discloses a silicon wafer cleaning agent having a fine concavo-convex pattern on the surface. The silicon wafer cleaning agent is used to repel water at least in the aqueous cleaning liquid and at least the concave portions of the concavo-convex pattern during the cleaning process. A water-repellent cleaning liquid, wherein the water-repellent cleaning liquid is a mixture of a water-repellent compound containing a reactive site capable of chemically bonding to silicon element of a silicon wafer and a hydrophobic group, and an organic solvent containing at least an alcohol solvent. There is disclosed a method for cleaning a silicon wafer surface using a silicon wafer cleaning agent characterized in that

  In addition, a wafer having a silicon element on the surface has been generally used as the wafer, but with the diversification of patterns, elements such as titanium, tungsten, aluminum, copper, tin, tantalum, and ruthenium are surfaced. The wafers that are included in are starting to be used. In Patent Document 13, in a wafer having a fine concavo-convex pattern formed on the surface, at least a part of the concave surface of the concavo-convex pattern is made of titanium, titanium nitride, tungsten, aluminum, copper, tin, tantalum nitride, ruthenium, and silicon. When cleaning a wafer containing at least one substance selected from the group consisting of: a chemical solution containing at least a water repellent protective film forming agent for forming a water repellent protective film on the surface of the recess, the pattern collapses on the wafer. It has been disclosed that the washing process that is likely to induce odor can be improved.

JP 2008-198958 A Japanese Patent Laid-Open No. 5-299336 Special table 2008-547050 gazette Japanese Patent No. 4403202 JP 2010-114467 A JP 2010-129932 A International Publication No. 2010/047196 Pamphlet US Patent Publication No. 2010/0122711 International Publication No. 2010/074134 Pamphlet JP 2010-192878 A JP 2010-192879 A JP 2010-272852 A Japanese Patent No. 4743340

  The present invention relates to a substrate (wafer) cleaning technique for the purpose of improving the manufacturing yield of a device having a circuit pattern that is fine and having a high aspect ratio, particularly in the manufacture of semiconductor devices. The present invention relates to a water-repellent chemical solution and the like intended to improve a cleaning process that easily induces a collapse of a concavo-convex pattern of a wafer having a surface. Patent Documents 4 and 5 describe that annealing treatment is performed to increase the liquid temperature to promote the reaction of the surface treatment agent, but the surface treatment agent is quickly spread over the surface of the object to be treated ( Is not considered at all, and the reaction of the surface treatment agent is accelerated enough to form a water-repellent film even in the middle of the substitution that is not completely substituted, There is room for improvement in reducing the time required for the surface treatment. In addition, Patent Documents 6 to 13 also have room for improvement in reducing the time required for the surface treatment for the same reason. The present invention is effective in preventing the collapse of the concave-convex pattern by forming a water-repellent coating on at least the concave surface of the wafer and reducing the interaction between the liquid held in the concave portion and the concave surface. It is an object of the present invention to provide a cleaning method capable of cleaning a wafer economically and more efficiently without impairing throughput.

The method for cleaning a wafer of the present invention is a method for cleaning a wafer having a concavo-convex pattern on the surface, and at least,
Cleaning the wafer with a cleaning liquid;
A step of replacing the cleaning liquid held in the recesses of the wafer with a water repellent chemical after the cleaning,
A step of drying the wafer;
The cleaning liquid contains 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C.,
The temperature of the water-repellent chemical solution provided in the replacing step is set to 40 ° C. or higher and lower than the boiling point of the water-repellent chemical solution, so that at least the surface of the concave portion is water-repellent. In the present specification, the boiling point means a value in a state of 1 atm. Further, the boiling point of the water-repellent chemical liquid means the boiling point of the component having the largest amount by mass ratio among the components contained in the water-repellent chemical liquid.

  Pattern collapse occurs when the gas-liquid interface passes through the pattern during drying after the wafer is cleaned with the cleaning liquid. This is said to be caused by a difference in residual liquid height between the portion having a large aspect ratio of the pattern and a portion having a small aspect ratio, thereby causing a difference in capillary force acting on the pattern.

  For this reason, if the capillary force is reduced, it can be expected that the difference in capillary force due to the difference in the residual liquid height will be reduced and the pattern collapse will be eliminated. The magnitude of the capillary force is the absolute value of P obtained by the following formula. From this formula, it is expected that the capillary force can be reduced by reducing γ or cos θ.

P = 2 × γ × cos θ / S
(Wherein γ is the surface tension of the liquid held in the recess, θ is the contact angle between the recess surface and the liquid held in the recess, and S is the width of the recess.)

  The water-repellent chemical solution forms a water-repellent coating on at least the concave surface of the concave / convex pattern, thereby reducing the surface energy of the portion, and mutual (interface) between water or other liquid and the surface of the portion. Actions such as hydrogen bonds and intermolecular forces are reduced. In particular, the effect of reducing the interaction with water is great, but it has the effect of reducing the interaction with a mixed liquid of water and a liquid other than water or a liquid other than water. Thereby, the contact angle of the liquid with respect to the article | item surface can be enlarged.

  As described above, the water-repellent coating is formed on at least the concave surface of the concavo-convex pattern while the cleaning liquid is replaced with the water-repellent chemical liquid and the chemical liquid is held in at least the concave portion of the concavo-convex pattern. For this reason, when the liquid is removed from the concave portion, that is, when dried, the water-repellent coating is formed on at least the concave surface of the concave / convex pattern, so that the capillary force acting on the concave portion is reduced and the pattern collapses. Is less likely to occur.

  Further, in order to form a water-repellent film in a short time on at least the concave surface of the concavo-convex pattern using the water-repellent chemical liquid, the film-forming ability of the chemical liquid is increased, and the cleaning liquid held in the concave section It is effective to replace water with a water-repellent chemical solution quickly.

  When the temperature of the water-repellent chemical solution provided in the replacing step is 40 ° C. or higher, the reaction and adsorption of the water-repellent chemical solution are promoted, and the film-forming ability is increased. As a result, the water-repellent film is formed in a short time. become able to. In addition, a water-repellent film can be sufficiently formed even in the middle of replacement that has not been completely replaced. However, it is not preferable that the temperature of the water-repellent chemical solution is the boiling point of the chemical solution because the chemical solution is likely to evaporate quickly and the wafer surface is easily dried. For this reason, the water-repellent chemical liquid is 40 ° C. or higher, less than the boiling point of the water-repellent chemical liquid, preferably 50 ° C. or higher, (less than (the boiling point of the water-repellent chemical liquid −10 ° C.)), more preferably 70 ° C. or higher. It is made to serve on the wafer surface at a temperature lower than the boiling point of the aqueous chemical solution (-10 ° C.).

  Further, if the cleaning liquid contains 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C., when the water-repellent chemical liquid having a temperature of 40 ° C. or higher is supplied, the cleaning liquid easily evaporates. This cleaning solution is easily replaced with a water-repellent chemical solution in a short time. As a result, a water-repellent film is formed in a short time. Furthermore, when the temperature of the supplied chemical liquid is 40 ° C. or higher and lower than the boiling point of the chemical liquid, diffusion and convection easily occur between the cleaning liquid held in the concave portions of the concave-convex pattern, and as a result. The cleaning liquid can be replaced with a water-repellent chemical liquid in a short time. For this reason, the cleaning liquid particularly preferably contains 80% by mass or more of a solvent having a boiling point of 60 to 180 ° C., and further preferably contains 80% by mass or more of a solvent having a boiling point of 70 to 160 ° C. If the cleaning liquid contains 80% by mass or more of a solvent having a boiling point of less than 55 ° C., in the step of replacing the cleaning liquid with a water-repellent chemical liquid, a chemical liquid having a temperature of 40 ° C. or higher and lower than the boiling point of the water-repellent chemical liquid is used. When supplied, the cleaning liquid may bump up or the evaporation speed of the cleaning liquid may become too fast. As a result, there is a risk of damage to the concavo-convex pattern due to generation of bubbles or bumping. Further, when the cleaning liquid contains 80% by mass or more of a solvent having a boiling point exceeding 200 ° C., in the step of replacing the cleaning liquid with a water repellent chemical liquid, a chemical liquid having a temperature of 40 ° C. or higher and lower than the boiling point of the water repellent chemical liquid is used. When supplied, the evaporation of the cleaning liquid is slow, so that the replacement tends to take a long time. As a result, the wafer surface tends to take a long time to develop water repellency. In addition, it is more preferable that the cleaning liquid is a solvent having a boiling point of 55 to 200 ° C., because it becomes easy to control the temperature of the water-repellent chemical liquid for avoiding rapid evaporation of the cleaning liquid, generation of bubbles, and bumping.

  The cleaning liquid is preferably at least one liquid selected from the group consisting of an organic solvent, water, and an aqueous solution in which at least one of an organic solvent, an acid, an alkali, and an oxidizing agent is mixed in water. In addition, an aqueous solution in which at least one of water, water, an organic solvent, an acid, an alkali, and an oxidizing agent is mixed may be hereinafter referred to as an aqueous liquid.

  The water-repellent chemical solution is used by substituting the chemical solution with a cleaning solution in the step of cleaning the wafer on which the uneven pattern is formed. Further, the substituted water repellent chemical liquid may be replaced with another cleaning liquid.

  The water-repellent coating does not necessarily have to be formed continuously, and does not necessarily have to be formed uniformly. However, since it can impart better water repellency, the water-repellent coating can be applied continuously and uniformly. More preferably, it is formed.

The wafer is a wafer containing a silicon element on the surface of the concave portion of the concave / convex pattern (hereinafter sometimes referred to as “silicon-based wafer”), and the water repellent chemical liquid is represented by the following general formula [1]. It is preferable that the compound A is included, or silicon compound A and an acid or a base are included. In addition, a method of cleaning a silicon-based wafer using the water-repellent chemical solution for silicon-based wafer is described as a first aspect of the present invention (hereinafter may be referred to as “first method”). In addition, the said chemical | medical solution may be described as "the water repellent chemical | medical solution for silicon wafers."
(R ¹ ) _a Si (H) _b X ¹ _4-ab [1]
[In the formula [1], each R ¹ independently contains a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. Valent organic group. X ¹ is independently of each other a monovalent functional group in which the element bonded to the silicon element is nitrogen, a monovalent functional group in which the element bonded to the silicon element is oxygen, a halogen group, a nitrile group, And at least one group selected from the group consisting of —CO—NH—Si (CH ₃ ) ₃ . 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. ]

The water-repellent chemical solution contains an acid, and the acid is hydrogen chloride, sulfuric acid, perchloric acid, phosphoric acid, a sulfonic acid represented by the following general formula [2] and its anhydride, and the following general formula [3]. From the carboxylic acid represented by the following formula: It is preferably at least one selected from the group consisting of
R ² S (O) ₂ OH [2]
[In the formula [2], R ² is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. ]
R ³ COOH [3]
[In the formula [3], R ³ is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. ]
(R ⁴ ) _c Si (H) _d X ² _4-cd [4]
[In the formula [4], each R ⁴ independently represents a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. X ² is independently of each other a chloro group, —OCO—R ⁵ (R ⁵ is a C 1 -C 1, wherein some or all of the hydrogen elements may be replaced by fluorine elements. Valent hydrocarbon group) and —OS (O) ₂ —R ⁶ (R ⁶ is a monovalent hydrocarbon having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements) Represents at least one group selected from the group consisting of (hydrocarbon groups). 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. ]

  Further, the acid is preferably a silicon compound B represented by the general formula [4]. Trimethylsilyl trifluoroacetate, trimethylsilyl trifluoromethanesulfonate, dimethylsilyl trifluoroacetate, dimethylsilyl trifluoromethanesulfonate, butyldimethylsilyl trifluoroacetate , Butyldimethylsilyl trifluoromethanesulfonate, hexyldimethylsilyl trifluoroacetate, hexyldimethylsilyl trifluoromethanesulfonate, octyldimethylsilyl trifluoroacetate, octyldimethylsilyl trifluoromethanesulfonate, decyldimethylsilyl trifluoroacetate, decyldimethylsilyl trifluoromethanesulfonate, Dodecyldimethylsilyl trifluoro Acetate, is preferably at least one selected from the group consisting of dodecyl butyldimethylsilyl trifluoromethanesulfonate.

The water-repellent chemical solution contains a base, which is ammonia, N, N, N ′, N′-tetramethylethylenediamine, triethylenediamine, dimethylaniline, alkylamine, dialkylamine, trialkylamine, pyridine, piperazine , N-alkylmorpholine, and at least one selected from the group consisting of silicon compounds C represented by the following general formula [5] is preferable.
(R ⁷ ) _e Si (H) _f X ³ _4-ef [5]
[In the formula [5], R ⁷ are each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. In addition, X ³ is a monovalent functional group that is independent of each other, and the element bonded to the silicon element is nitrogen, and may contain a fluorine element or a silicon 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 1 to 3. ]

In the water-repellent film formed using the water-repellent chemical solution for silicon-based wafer, X ^{1 in the} general formula [1] reacts with a silanol group which is a reaction site on the surface of the silicon-based wafer, and the silicon compound A is silicon-based. It is formed by chemically bonding with the silicon element of the wafer. R ^{1 in the} general formula [1] reduces the surface energy of the concave portion, and interacts between water or other liquid and the surface of the water-repellent coating (interface), for example, hydrogen bond, intermolecular force. The contact angle of the liquid with respect to the article surface can be increased.

  Said acid or base which may be contained in a chemical | medical solution is effective in promoting reaction with the said silicon compound A and the silicon element of a silicon-type wafer. When the acid or base is present in the water-repellent chemical solution for a silicon-based wafer, a water-repellent coating can be formed in a short time. The speed at which the water-repellent film is formed on the silicon-based wafer surface, that is, the speed at which the water-repellent property is developed on the silicon-based wafer surface is determined by the component derived from the silicon compound A binding to the reaction site on the silicon-based wafer surface. It depends on the speed. When the above acid or base is present, the component derived from the silicon compound A can quickly react with silanol groups, which are reaction sites on the surface of the concave / convex pattern of the silicon-based wafer. Water repellency can be imparted. The acid or base may form part of the water repellent coating.

  The silicon compound A is hexamethyldisilazane, trimethylsilyldimethylamine, trimethylsilyldiethylamine, tetramethyldisilazane, dimethylsilyldimethylamine, dimethylsilyldiethylamine, 1,3-dibutyltetramethyldisilazane, butyldimethylsilyldimethylamine, Butyldimethylsilyldiethylamine, 1,3-dihexyltetramethyldisilazane, hexyldimethylsilyldimethylamine, hexyldimethylsilyldiethylamine, 1,3-dioctyltetramethyldisilazane, octyldimethylsilyldimethylamine, octyldimethylsilyldiethylamine, 1,3 -Didecyltetramethyldisilazane, decyldimethylsilyldimethylamine, decyldimethylsilyldiethylamine, 1,3 Didodecyl tetramethyldisilazane, dodecyl dimethyl silyl dimethylamine, is preferably at least one selected from the group consisting of dodecyl dimethyl silyl diethylamine.

The wafer may be described as at least one element of titanium, tungsten, aluminum, copper, tin, tantalum, and ruthenium (hereinafter, “metal element”) on the surface of the concave portion of the concave / convex pattern. ), And the water-repellent chemical solution is composed of a compound represented by the following general formulas [6] to [12] and a salt compound thereof. It is preferable that it contains at least one selected from the group and a solvent. In addition, the said chemical | medical solution may be described as "the water-repellent chemical | medical solution for metal type wafers". In addition, a method of cleaning a metal-based wafer using the water-repellent chemical solution for a metal-based wafer is described as a second aspect of the present invention (hereinafter sometimes referred to as “second method”).
_{^{R 8 -P (= O) -}} (OH) g (R 9) 2-g [6]
[In Formula [6], R ⁸ is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. R ⁹ is each independently a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced with fluorine elements. g is an integer of 0 to 2. ]
R ¹⁰ —C (═O) —X ⁴ [7]
[In the formula [7], R ¹⁰ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. . X ⁴ represents a group selected from the group consisting of a fluoro group, a chloro group, a bromo group, and an iodo group. ]
R ¹¹ R ¹² R ¹³ N [8]
[In the formula [8], R ¹¹ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. R ¹² is a hydrogen element, a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms, or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. R ¹³ is a hydrogen element, a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms, or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. ]
R ¹⁴ —C (═O) —X ⁵ —X ⁶ [9]
[In the formula [9], R ¹⁴ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. . X ⁵ represents an oxygen element or a sulfur element, and X ⁶ represents a hydrogen element, an alkyl group, an aromatic group, a pyridyl group, a quinolyl group, a succinimide group, a maleimide group, a benzoxazole group, a benzothiazole group, and a benzoic acid group. The group chosen from the group which consists of a triazole group is shown, The hydrogen element in these groups may be substituted by the organic group. ]
R ¹⁵ (X ⁷ ) _h [10]
[In Formula [10], X ⁷ is each independently at least one group selected from the group consisting of an isocyanate group, a mercapto group, an aldehyde group, a —CONHOH group, and a ring structure containing a nitrogen element. , H is an integer of 1 to 6, R ¹⁵ is an organic group containing a hydrocarbon group having 1 to 18 carbon atoms, or an organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms, In which the same number of hydrogen elements are substituted with at least one group selected from the group consisting of an isocyanate group, a mercapto group, an aldehyde group, a —CONHOH group, and a ring structure containing a nitrogen element. ]
R ¹⁶ -X ⁸ [11]
[In the formula [11], X ⁸ is a ring structure containing a sulfur element, R ¹⁶ is a hydrogen element, a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms, or 1 carbon atom. A monovalent organic group containing from 8 to 8 fluoroalkyl chains. ]
R ¹⁷ —C (═O) —X ⁹ —C (═O) —R ¹⁸ [12]
[In the formula [12], R ¹⁷ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. . R ¹⁸ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. X ⁹ represents an oxygen element or a sulfur element. ]

The water-repellent film formed using the water-repellent chemical solution for metal-based wafers is obtained by using a compound selected from the compounds represented by the general formulas [6] to [12] and a salt compound thereof. It can be formed on at least the concave surface of the system wafer. The water-repellent coating is formed by adsorbing a functional part having affinity for a substance containing a metal element to the surface of the substance containing the metal element and / or the functional part and the substance surface. This is done by adsorbing by reacting to form chemical bonds. The functional part is a group represented by a P—OH group and / or a P═O group in the general formula [6], and represented by —C (═O) —X ⁴ in the general formula [7]. In the general formula [8], it is an N element, in the general formula [9], it is a group represented by —C (═O) —X ⁵ —X ⁶ , and in the general formula [10] ( X ⁷ ) is a group represented by _h , is a group represented by —X ⁸ in the general formula [11], and —C (═O) —X ⁹ —C (═O) in the general formula [12]. It is group represented by-. Here, having affinity means that van der Waals force, electrostatic interaction, or the like acts between the surface of the substance containing the metal element and the functional part of the compound. Also, R ^{8 of} the general formula [6], R ^{10 of} the general formula [7], R ^{11 of} the general formula [8], R ^{14 of} the general formula [9], R ^{15 of} the general formula [10], the general formula R ^{16 of} [11] and R ¹⁷ and R ¹⁸ of the general formula [12] are hydrophobic portions of the compound, and when the compound is adsorbed to the metal element of the metal wafer, the metal system The hydrophobic portions are arranged from the wafer surface to the outside, and as a result, the surface energy of the concave portion is reduced, and interaction (water interface) between water or other liquid and the water-repellent coating surface (for example, hydrogen bonding) , Has the effect of reducing intermolecular forces and the like. Thereby, the contact angle of the liquid with respect to the article | item surface can be enlarged.

  The present invention is also a water-repellent chemical solution used in any of the above wafer cleaning methods.

  In this specification, when referring to both a silicon-based wafer and a metal-based wafer, the term “wafer” may be used. Moreover, when referring to both the water-repellent chemical liquid for silicon-based wafers and the water-repellent chemical liquid for metal-based wafers, it may be simply referred to as “water-repellent chemical liquid”.

  The cleaning method of the present invention is effective in preventing the collapse of the concavo-convex pattern by forming a water-repellent film on the concave surface of the wafer and reducing the interaction between the liquid held in the concave portion and the concave surface. The water-repellent coating can be formed in a short time. Therefore, the method for producing a wafer having a concavo-convex pattern on the surface, which is performed using the water repellent chemical solution of the present invention, has high productivity.

It is a figure which shows an example of the schematic diagram when the wafer 1 by which the surface was made into the surface which has the uneven | corrugated pattern 2 is seen. FIG. 2 shows a part of the a-a ′ cross section in FIG. 1. The schematic diagram of the state in which the recessed part 4 hold | maintained the washing | cleaning liquid 8 in the washing | cleaning process is shown. The schematic diagram of the state where the water-repellent chemical liquid 9 is provided on the wafer in which the cleaning liquid 8 is held in the recess 4 in the cleaning process is shown. In the replacement step, a schematic view showing a state in which the concave portion 4 holds the water-repellent chemical liquid 9 and the water-repellent coating 12 is formed.

The present invention is a method for cleaning a wafer having a concavo-convex pattern on the surface, at least,
Cleaning the wafer with a cleaning liquid;
A step of replacing the cleaning liquid held in the recesses of the wafer with a water repellent chemical after the cleaning,
A step of drying the wafer;
The cleaning liquid contains 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C.,
The temperature of the water-repellent chemical solution provided in the replacing step is set to 40 ° C. or higher and lower than the boiling point of the water-repellent chemical solution, so that at least the surface of the concave portion is water-repellent.

  When a wafer having a concavo-convex pattern on the surface is washed with various liquids and the liquid is removed by drying or the like, pattern collapse tends to occur when the width of the concave portion is small and the aspect ratio of the convex portion is large. The concavo-convex pattern is defined as shown in FIGS. FIG. 1 shows an example of a schematic view when a wafer 1 whose surface is a surface having a concavo-convex pattern 2 is viewed, and FIG. 2 shows a part of a cross section aa ′ in FIG. 1. . As shown in FIG. 2, the width 5 of the concave portion is indicated by the interval between the convex portion 3 and the convex portion 3, and the aspect ratio of the convex portion is expressed by dividing the height 6 of the convex portion by the width 7 of the convex portion. Is done. Pattern collapse in the cleaning process tends to occur when the width of the recess is 70 nm or less, particularly 45 nm or less, and the aspect ratio is 4 or more, particularly 6 or more.

  In the cleaning method of the present invention, the cleaning liquid containing 80% by mass or more of the solvent having a boiling point of 55 to 200 ° C. is held in at least the recesses of the uneven pattern, and the cleaning liquid is held in at least the recesses of the uneven pattern. The cleaning liquid is replaced with the water repellent chemical liquid.

  FIG. 3 is a schematic view showing a state in which the recess 4 holds the cleaning liquid 8 in the cleaning process. The wafer in the schematic diagram of FIG. 3 shows a part of the a-a ′ cross section of FIG. 1. A water-repellent chemical solution is provided to the wafer in which the cleaning liquid 8 is held in the recess 4 in the cleaning process.

  FIG. 4 shows a schematic view of a state in which the water repellent chemical liquid 9 is provided to the wafer in which the concave portion 4 holds the cleaning liquid 8. At this time, the recess is replaced with the water repellent chemical 9 from the cleaning liquid 8, but the cleaning liquid 8 contains 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C. Since it is heated to above the boiling point of the water repellent chemical solution at a temperature of 0 ° C. or more, for example, the mixing of the cleaning liquid and the water repellent chemical solution easily proceeds by diffusion or convection as indicated by 10 in the figure. As shown, the evaporation of the cleaning liquid easily proceeds, and as a result, the replacement proceeds in a short time.

  FIG. 5 is a schematic view showing a state in which the concave portion 4 holds the water-repellent chemical liquid 9 and the water-repellent coating 12 is formed in the replacement step. By forming the water-repellent coating 12 on the surface of the recess 4, the surface is water-repellent.

  Hereinafter, the first method will be described. The water-repellent chemical solution for silicon-based wafers preferably contains the silicon compound A represented by the general formula [1], or contains the silicon compound A and an acid or base.

The monovalent functional group of nitrogen that is an element bonded to the silicon element, which is an example of X ^{1 in} the general formula [1], includes not only hydrogen, carbon, nitrogen, and oxygen but also elements such as silicon, sulfur, and halogen. It may be included. Examples of the functional group include isocyanate group, amino group, dialkylamino group, isothiocyanate group, azide group, acetamide group, —N (CH ₃ ) C (O) CH ₃ , —N (CH ₃ ) C (O ) CF ₃ , —N═C (CH ₃ ) OSi (CH ₃ ) ₃ , —N═C (CF ₃ ) OSi (CH ₃ ) ₃ , —NHC (O) —OSi (CH ₃ ) ₃ , —NHC ( O) —NH—Si (CH ₃ ) ₃ , an imidazole ring (the following formula [13]), an oxazolidinone ring (the following formula [14]), a morpholine ring (the following formula [15]), —NH—C (O) — _{Si (CH 3) 3, -N} (H) 2-i (Si (H) j R 19 3-j) i (R 19 , a part or all of the hydrogen elements may be replaced by fluorine element A monovalent hydrocarbon group having 1 to 18 carbon atoms, i is 1 or 2, and j is 0 2 of integer), and the like.

In addition, the monovalent functional group in which the element bonded to the silicon element which is an example of X ^{1 in} the general formula [1] is oxygen includes not only hydrogen, carbon, nitrogen, and oxygen but also silicon, sulfur, halogen, and the like. An element may be contained. Examples of the organic group, an alkoxy _{group, -OC (CH 3) = CHCOCH} 3, -OC (CH 3) = N-Si (CH 3) 3, -OC (CF 3) = N-Si (CH 3 ) ₃ , —O—CO—R ²⁰ (R ²⁰ is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be substituted with fluorine elements, etc.), some Alternatively, there is an alkyl sulfonate group in which all hydrogen elements may be substituted with fluorine element or the like.

Examples of the halogen group as an example of X ^{1 in} the general formula [1] include a chloro group, a bromo group, and an iodo group.

Further, R ^{1 in the} general formula [1] reduces the surface energy of the water-repellent coating, and interacts between water or other liquid and the surface of the water-repellent coating (interface), for example, hydrogen bonding It is a hydrophobic part that reduces intermolecular forces and the like. In particular, the effect of reducing the interaction with water is great, but it has the effect of reducing the interaction with a mixed liquid of water and a liquid other than water or a liquid other than water. Thereby, the contact angle of the liquid with respect to the article | item surface can be enlarged.

Examples of the silicon compound A represented by the general formula [1] include CH ₃ Si (OCH ₃ ) ₃ , C ₂ H ₅ Si (OCH ₃ ) ₃ , C ₃ H ₇ Si (OCH ₃ ) ₃ , C ₄ H ₉ Si (OCH ₃ ) ₃ , C ₅ H ₁₁ Si (OCH ₃ ) ₃ , C ₆ H ₁₃ Si (OCH ₃ ) ₃ , C ₇ H ₁₅ Si (OCH ₃ ) ₃ , C ₈ H ₁₇ Si (OCH ₃ ) ₃ , C ₉ H ₁₉ Si (OCH ₃ ) ₃ , C ₁₀ H ₂₁ Si (OCH ₃ ) ₃ , C ₁₁ H ₂₃ Si (OCH ₃ ) ₃ , C ₁₂ H ₂₅ Si (OCH ₃ ) ₃ , C _{13 H 27 Si (OCH 3) 3} , C 14 H 29 Si (OCH 3) 3, C 15 H 31 Si (OCH 3) 3, C 16 H 33 Si (OCH 3) 3, C 17 H 35 Si (OCH 3 ) _3, C _{8 H 37 Si (OCH 3)} 3, (CH 3) 2 Si (OCH 3) 2, C 2 H 5 Si (CH 3) (OCH 3) 2, (C 2 H 5) 2 Si (OCH 3) 2 _{, C 3 H 7 Si (CH} 3) (OCH 3) 2, (C 3 H 7) 2 Si (OCH 3) 2, C 4 H 9 Si (CH 3) (OCH 3) 2, (C 4 H 9 ) ₂ Si (OCH ₃ ) ₂ , C ₅ H ₁₁ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₆ H ₁₃ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₇ H ₁₅ Si (CH ₃ ) (OCH _{3) 2, C 8 H 17} Si (CH 3) (OCH 3) 2, C 9 H 19 Si (CH 3) (OCH 3) 2, C 10 H 21 Si (CH 3) (OCH 3) 2, C _{11 H 23 Si (CH 3)} (OCH 3) 2, C 12 _{25 Si (CH 3) (OCH} 3) 2, C 13 H 27 Si (CH 3) (OCH 3) 2, C 14 H 29 Si (CH 3) (OCH 3) 2, C 15 H 31 Si (CH 3 ) (OCH ₃ ) ₂ , C ₁₆ H ₃₃ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₁₇ H ₃₅ Si (CH ₃ ) (OCH ₃ ) ₂ , C ₁₈ H ₃₇ Si (CH ₃ ) (OCH ₃ ) ₂ , (CH ₃ ) ₃ SiOCH ₃ , C ₂ H ₅ Si (CH ₃ ) ₂ OCH ₃ , (C ₂ H ₅ ) ₂ Si (CH ₃ ) OCH ₃ , (C ₂ H ₅ ) ₃ SiOCH ₃ , C ₃ H ₇ Si (CH ₃ ) ₂ OCH ₃ , (C ₃ H ₇ ) ₂ Si (CH ₃ ) OCH ₃ , (C ₃ H ₇ ) ₃ SiOCH ₃ , C ₄ H ₉ Si (CH ₃ ) ₂ OCH ₃ , ( C ₄ H _{9) 3} SiOC _{3, C 5 H 11 Si (} CH 3) 2 OCH 3, C 6 H 13 Si (CH 3) 2 OCH 3, C 7 H 15 Si (CH 3) 2 OCH 3, C 8 H 17 Si (CH 3) ₂ OCH ₃ , C ₉ H ₁₉ Si (CH ₃ ) ₂ OCH ₃ , C ₁₀ H ₂₁ Si (CH ₃ ) ₂ OCH ₃ , C ₁₁ H ₂₃ Si (CH ₃ ) ₂ OCH ₃ , C ₁₂ H ₂₅ Si (CH _{3) 2 OCH 3, C 13} H 27 Si (CH 3) 2 OCH 3, C 14 H 29 Si (CH 3) 2 OCH 3, C 15 H 31 Si (CH 3) 2 OCH 3, C 16 H 33 Si _{(CH 3) 2 OCH 3,} C 17 H 35 Si (CH 3) 2 OCH 3, C 18 H 37 Si (CH 3) 2 OCH 3, (CH 3) 2 Si (H) OCH 3, CH 3 _{i (H) 2 OCH 3,} (C 2 H 5) 2 Si (H) OCH 3, C 2 H 5 Si (H) 2 OCH 3, C 2 H 5 Si (CH 3) (H) OCH 3, ( C ₃ H ₇₎ alkyl silane such as ₂ Si (H) OCH _{3 or,, CF 3 CH 2 CH 2} Si (OCH 3) 3, C 2 F 5 CH 2 CH 2 Si (OCH 3) 3, C 3 _{F 7 CH 2 CH 2 Si (} OCH 3) 3, C 4 F 9 CH 2 CH 2 Si (OCH 3) 3, C 5 F 11 CH 2 CH 2 Si (OCH 3) 3, C 6 F 13 CH 2 CH ₂ Si (OCH ₃ ) ₃ , C ₇ F ₁₅ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₈ F ₁₇ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , CF ₃ CH ₂ CH ₂ Si (CH ₃ ) ( OCH _{3) 2, C 2 5 CH 2 CH 2 Si (CH} 3) (OCH 3) 2, C 3 F 7 CH 2 CH 2 Si (CH 3) (OCH 3) 2, C 4 F 9 CH 2 CH 2 Si (CH 3) (OCH _{3) 2, C 5 F 11} CH 2 CH 2 Si (CH 3) (OCH 3) 2, C 6 F 13 CH 2 CH 2 Si (CH 3) (OCH 3) 2, C 7 F 15 CH 2 CH 2 _{Si (CH 3) (OCH 3} ) 2, C 8 F 17 CH 2 CH 2 Si (CH 3) (OCH 3) 2, CF 3 CH 2 CH 2 Si (CH 3) 2 OCH 3, C 2 F 5 CH _{2 CH 2 Si (CH 3)} 2 OCH 3, C 3 F 7 CH 2 CH 2 Si (CH 3) 2 OCH 3, C 4 F 9 CH 2 CH 2 Si (CH 3) 2 OCH 3, C 5 F 11 CH ₂ CH ₂ Si (CH ₃ ) ₂ OCH ₃ , C ₆ F ₁₃ CH ₂ CH ₂ Si (CH ₃ ) ₂ OCH ₃ , C ₇ F ₁₅ CH ₂ CH ₂ Si (CH ₃ ) ₂ OCH ₃ , C ₈ F ₁₇ CH ₂ CH _{2 Si (CH 3) 2 OCH 3} , CF 3 CH 2 CH 2 Si (CH 3) (H) fluoroalkyl silane of OCH _3, etc. Alternatively, the alkyl methoxysilane and methyl methoxy groups of the fluoroalkyl silane An alkoxysilane compound in which a portion is replaced with a monovalent hydrocarbon group having 2 to 18 carbon atoms, or the methoxy group is converted to —OC (CH ₃ ) ═CHCOCH ₃ , —OC (CH ₃ ) = N—Si. (CH ₃ ) ₃ , —OC (CF ₃ ) ═N—Si (CH ₃ ) ₃ , —O—CO—R ²⁰ (R ²⁰ is a part or all of hydrogen elements. A monovalent hydrocarbon group having 1 to 18 carbon atoms which may be substituted with fluorine element, etc.), an alkyl sulfonate group, an isocyanate group, wherein some or all of the hydrogen elements may be substituted with fluorine element, etc. amino group, a dialkylamino group, an isothiocyanate group, an azide group, acetamido _{group, -N (CH 3) C (} O) CH 3, -N (CH 3) C (O) CF 3, -N = C (CH 3 ) OSi (CH ₃ ) ₃ , —N═C (CF ₃ ) OSi (CH ₃ ) ₃ , —NHC (O) —OSi (CH ₃ ) ₃ , —NHC (O) —NH—Si (CH ₃ ) ₃ , an imidazole ring, an oxazolidinone ring, morpholine _{ring, -NH-C (O) -Si} (CH 3) 3, -N (H) 2-i (Si (H) j R 19 3-j) i (R 19 is , Some or all of the hydrogen elements are fluorine A monovalent hydrocarbon group having 1 to 18 carbon atoms which may be replaced by an element, i is 1 or 2, and j is an integer of 0 to 2), a chloro group, a bromo group, an iodo group, a nitrile group, or , —CO—NH—Si (CH ₃ ) ₃ and the like.

Moreover, it is more preferable that the number of X ¹ of the silicon compound A represented by 4-ab in the general formula [1] is 1 because the water-repellent coating can be formed uniformly.

R ¹ in the general formula [1] is independently selected from monovalent hydrocarbon groups having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. At least one group, more preferably at least one group selected from C _m H _{2m + 1} (m = 1 to 18) and C _n F _{2n + 1} CH ₂ CH ₂ (n = 1 to 8), When a water-repellent film is formed on the surface of the concavo-convex pattern, the wettability of the surface can be lowered, that is, more excellent water repellency can be imparted to the surface, which is more preferable. Moreover, it is more preferable that m is 1 to 12 and n is 1 to 8 because a water-repellent film can be formed on the surface of the uneven pattern in a short time.

  Among these, the silicon compound A includes hexamethyldisilazane, trimethylsilyldimethylamine, trimethylsilyldiethylamine, tetramethyldisilazane, dimethylsilyldimethylamine, dimethylsilyldiethylamine, 1,3-dibutyltetramethyldisilazane, butyldimethylsilyldimethylamine. , Butyldimethylsilyldiethylamine, 1,3-dihexyltetramethyldisilazane, hexyldimethylsilyldimethylamine, hexyldimethylsilyldiethylamine, 1,3-dioctyltetramethyldisilazane, octyldimethylsilyldimethylamine, octyldimethylsilyldiethylamine, 1, 3-didecyltetramethyldisilazane, decyldimethylsilyldimethylamine, decyldimethylsilyldiethylamine, , 3-di-dodecyl tetramethyl disilazane, dodecyl dimethyl silyl dimethylamine, dodecyl dimethyl silyl diethylamine are particularly preferred.

  The acid includes hydrogen chloride, sulfuric acid, perchloric acid, phosphoric acid, the sulfonic acid represented by the general formula [2] and its anhydride, the carboxylic acid represented by the general formula [3] and its anhydrous And at least one selected from the group consisting of silicon compounds B represented by the above general formula [4], alkyl borate ester, aryl borate ester, tris (trifluoroacetoxy) boron, trialkoxyboroxine, trifluoroboron Preferably there is.

  Examples of the sulfonic acid represented by the general formula [2] and its anhydride include methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, trifluoromethanesulfonic anhydride, and the like. Examples of the carboxylic acid represented by [3] and its anhydride include acetic acid, trifluoroacetic acid, pentafluoropropionic acid, acetic anhydride, trifluoroacetic anhydride, pentafluoropropionic anhydride, and the like represented by the general formula [4]. As the silicon compound B represented by the formula, chlorosilane, alkylsilylalkyl sulfonate, and alkylsilyl ester are preferable, and trimethylsilyl trifluoroacetate, trimethylsilyl trifluoromethanesulfonate, dimethylsilyl trifluoroacetate, dimethylsilyl triflate. Oromethanesulfonate, butyldimethylsilyl trifluoroacetate, butyldimethylsilyl trifluoromethanesulfonate, hexyldimethylsilyl trifluoroacetate, hexyldimethylsilyl trifluoromethanesulfonate, octyldimethylsilyl trifluoroacetate, octyldimethylsilyl trifluoromethanesulfonate, decyldimethylsilyltriflate Examples include fluoroacetate, decyldimethylsilyl trifluoromethanesulfonate, dodecyldimethylsilyl trifluoroacetate, dodecyldimethylsilyl trifluoromethanesulfonate, and the like.

  The base includes ammonia, N, N, N ′, N′-tetramethylethylenediamine, triethylenediamine, dimethylaniline, alkylamine, dialkylamine, trialkylamine, pyridine, piperazine, N-alkylmorpholine, and the above general formula. It is preferably at least one selected from the group consisting of the silicon compound C represented by [5].

  The above-mentioned acid or base that may be contained in the chemical solution promotes the reaction between the silicon compound A and silanol groups that are reaction sites on the surface of the silicon-based wafer. Excellent water repellency can be imparted. The acid or base may form part of the water repellent coating.

  Considering the reaction promoting effect, it is preferable that the chemical solution contains an acid. Among them, Bronsted acid of strong acid such as hydrogen chloride, sulfuric acid and perchloric acid, trifluoromethanesulfonic acid and trifluoromethanesulfonic anhydride, Some or all of the hydrogen elements, such as alkane sulfonic acids in which some or all of the hydrogen elements are replaced with fluorine elements, their anhydrides, trifluoroacetic acid, trifluoroacetic anhydride, pentafluoropropionic acid, etc. Substituted carboxylic acids and acid anhydrides thereof, chlorosilanes, alkylsilylalkylsulfonates in which some or all of the hydrogen elements are substituted with fluorine elements, and alkylsilyl esters in which some or all of the hydrogen elements are substituted with fluorine elements Particularly preferred. Note that the alkylsilyl ester is a silicon element in which an alkyl group and —O—CO—R ′ group (R ′ is an alkyl group) are bonded. The acid contained in the chemical solution may be produced by a reaction. For example, the alkylalkoxysilane produced by reacting an alkylchlorosilane with an alcohol is the silicon compound A, and the produced hydrochloric acid is the acid. Alternatively, a water-repellent chemical solution using alcohol that has not been consumed in the reaction as a solvent may be obtained.

  Further, the acid is preferably a silicon compound B represented by the general formula [4]. Trimethylsilyl trifluoroacetate, trimethylsilyl trifluoromethanesulfonate, dimethylsilyl trifluoroacetate, dimethylsilyl trifluoromethanesulfonate, butyldimethylsilyl trifluoroacetate , Butyldimethylsilyl trifluoromethanesulfonate, hexyldimethylsilyl trifluoroacetate, hexyldimethylsilyl trifluoromethanesulfonate, octyldimethylsilyl trifluoroacetate, octyldimethylsilyl trifluoromethanesulfonate, decyldimethylsilyl trifluoroacetate, decyldimethylsilyl trifluoromethanesulfonate, Dodecyldimethylsilyl trifluoro Acetate, is preferably at least one selected from the group consisting of dodecyl butyldimethylsilyl trifluoromethanesulfonate.

The silicon compound B represented by the general formula [4] may be obtained by reaction. For example, at least one selected from the group consisting of silicon compound D represented by the following general formula [16] and trifluoroacetic acid, trifluoroacetic anhydride, trifluoromethanesulfonic acid, and trifluoromethanesulfonic anhydride (hereinafter referred to as “acid D”). May be obtained by reacting.
(R ²¹ ) _p (H) _q SiX ¹⁰ _4- pq [16]
(In Formula [16], each R ²¹ is independently selected from C _m H _{2m + 1} (m = 1 to 18) and C _n F _{2n + 1} CH ₂ CH ₂ (n = 1 to 8). 1 is a group, p is an integer of 1 to 3, q is an integer of 0 to 2, and the sum of p and q is 1 to 3. X ¹⁰ is bonded to a silicon element independently of each other. The element to be represented is a monovalent functional group of nitrogen. (R ²¹ ) _p (H) _q Si— includes (CH ₃ ) ₃ Si—, (CH ₃ ) ₂ (H) Si—, (C ₄ H _{9) (CH 3) 2 Si} -, (C 6 H 13) (CH 3) 2 Si -, (C 8 H 17) (CH 3) 2 Si-, _{and, (C 10 H 21) (} CH 3) ₂ Si-, (C ₁₂ H ₂₅ ) (CH ₃ ) ₂ Si—, and the like.

  For example, when hexamethyldisilazane is mixed as the silicon compound D and trifluoroacetic anhydride is mixed as the acid D, the trifluoroacetic anhydride reacts immediately to obtain trimethylsilyl trifluoroacetate as the silicon compound B.

  Also, for example, when hexamethyldisilazane is mixed as the silicon compound D and trifluoromethanesulfonic anhydride is mixed as the acid D, the trifluoromethanesulfonic anhydride reacts immediately to obtain trimethylsilyl trifluoromethanesulfonate as the silicon compound B. It is done.

  For example, when tetramethyldisilazane is mixed as the silicon compound D and trifluoroacetic anhydride is mixed as the acid D, the trifluoroacetic anhydride reacts immediately to obtain dimethylsilyl trifluoroacetate as the silicon compound B. .

  Also, for example, when tetramethyldisilazane is mixed as the silicon compound D and trifluoromethanesulfonic anhydride is mixed as the acid D, the trifluoromethanesulfonic anhydride reacts immediately, and dimethylsilyl trifluoromethanesulfonate as the silicon compound B becomes can get.

  Further, for example, when 1,3-dibutyltetramethyldisilazane is mixed as the silicon compound D and trifluoroacetic anhydride is mixed as the acid D, the trifluoroacetic anhydride reacts immediately to form butyldimethylsilyl as the silicon compound B. Trifluoroacetate is obtained.

  Further, for example, when 1,3-dibutyltetramethyldisilazane is mixed as the silicon compound D and trifluoromethanesulfonic anhydride is mixed as the acid D, the trifluoromethanesulfonic anhydride reacts immediately and butyl as the silicon compound B is reacted. Dimethylsilyl trifluoromethanesulfonate is obtained.

  In addition, for example, when 1,3-dioctyltetramethyldisilazane is mixed as the silicon compound D and trifluoroacetic anhydride is mixed as the acid D, the trifluoroacetic anhydride reacts immediately to form octyldimethylsilyl as the silicon compound B. Trifluoroacetate is obtained.

  Further, for example, when 1,3-dioctyltetramethyldisilazane is mixed as the silicon compound D and trifluoromethanesulfonic anhydride is mixed as the acid D, the trifluoromethanesulfonic anhydride reacts immediately to form octyl as the silicon compound B. Dimethylsilyl trifluoromethanesulfonate is obtained.

  Further, for example, when 1,3-didecyltetramethyldisilazane is mixed as the silicon compound D and trifluoroacetic anhydride is mixed as the acid D, the trifluoroacetic anhydride reacts immediately to form decyldimethyl as the silicon compound B. Silyl trifluoroacetate is obtained.

  Further, for example, when 1,3-didecyltetramethyldisilazane is mixed as the silicon compound D and trifluoromethanesulfonic anhydride is mixed as the acid D, the trifluoromethanesulfonic anhydride reacts immediately to form the silicon compound B as Decyldimethylsilyl trifluoromethanesulfonate is obtained.

  Also, for example, when octyldimethylsilyldimethylamine as silicon compound D and trifluoroacetic anhydride as acid D are mixed, trifluoroacetic anhydride reacts immediately, and octyldimethylsilyl trifluoroacetate as silicon compound B becomes can get.

  Also, for example, when decyldimethylsilyldimethylamine as silicon compound D and trifluoroacetic anhydride as acid D are mixed, trifluoroacetic anhydride reacts immediately and decyldimethylsilyl trifluoroacetate as silicon compound B becomes can get.

  In addition, the water-repellent chemical solution for a silicon-based wafer prepared by using at least one selected from trifluoroacetic anhydride and trifluoromethanesulfonic anhydride as the acid D and reacting with the silicon compound D to obtain the silicon compound B Alternatively, a water-repellent chemical solution for a silicon-based wafer prepared using the silicon compound A and the silicon compound B as starting materials is more preferable because of its excellent stability.

  In the water-repellent chemical solution for silicon-based wafers of the present invention, the silicon compound D is excessively added to the acid D, and the surplus of the silicon compound D not consumed in the reaction is formed as the silicon compound A to form the water-repellent film. It may contribute to. The silicon compound D is preferably 0.2 to 100000 mol times, preferably 0.5 to 50000 mol times, and more preferably 1 to 10,000 mol times with respect to the acid D. .

  In addition, as long as the silicon compound B represented by the general formula [4] is obtained, a reaction other than the reaction between the silicon compound D and the acid D may be used.

Wherein an X ¹⁰ of the general formula [16], the monovalent functional group of elements that bind to the silicon element is nitrogen, include hydrogen, carbon, nitrogen, oxygen as well as silicon, sulfur, an element such as a halogen It may be. Examples of monovalent functional groups in which the element bonded to the silicon element is nitrogen include isocyanate groups, amino groups, dialkylamino groups, isothiocyanate groups, azide groups, acetamide groups, —N (CH ₃ ) C (O) CH _{3, -N (CH 3) C} (O) CF 3, -N = C (CH 3) OSi (CH 3) 3, -N = C (CF 3) OSi (CH 3) 3, -NHC (O) _{-OSi (CH 3) 3, -NHC} (O) -NH-Si (CH 3) 3, an imidazole ring, an oxazolidinone ring, morpholine _{ring, -NH-C (O) -Si} (CH 3) 3, -N ( H) _2-i (Si (H) _j R ¹⁹ _3-j ) _i (R ¹⁹ is a monovalent monovalent having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. A hydrocarbon group, i is 1 or 2, j is an integer of 0-2) Etc. there is.

Examples of the silicon compound D of the formula [16] include (CH ₃ ) ₃ SiNH ₂ , C ₄ H ₉ Si (CH ₃ ) ₂ NH ₂ , C ₆ H ₁₃ Si (CH ₃ ) ₂ NH ₂ , C _{8. H 17 Si (CH 3) 2} NH 2, C 10 H 21 Si (CH 3) 2 NH 2, C 12 H 25 Si (CH 3) 2 NH 2, (CH 3) 2 Si (H) of the NH ₂ aminosilane Alternatively, the amino group (—NH ₂ group) of the aminosilane is represented by —N═C═O, —N (CH ₃ ) ₂ , —N (C ₂ H ₅ ) ₂ , —N═C═S, —N _{3, -NHC (O) CH 3} , -N (CH 3) C (O) CH 3, -N (CH 3) C (O) CF 3, -N = C (CH 3) OSi (CH 3) 3 _{, -N = C (CF 3)} OSi (CH 3) 3, -NHC (O) -OSi (CH ₃ ) ₃ , —NHC (O) —NH—Si (CH ₃ ) ₃ , imidazole ring, oxazolidinone ring, morpholine ring, —NH—C (O) —Si (CH ₃ ) ₃ , —NH—Si (CH ₃₎ ) ₃ , —NH—Si (H) (CH ₃ ) ₂ , —NH—Si (CH ₃ ) ₂ (C ₄ H ₉ ), —NH—Si (CH ₃ ) ₂ (C ₆ H ₁₃ ), —NH _{-Si (CH 3) 2 (C} 8 H 17), - NH-Si (CH 3) 2 (C 10 H 21), - NH-Si (CH 3) 2 (C 12 H 25), - NH-Si Examples include (CH ₃ ) ₂ (C ₂ H ₄ C ₆ F ₁₃ ) and —N— {Si (CH ₃ ) ₃ } ₂ .

  Among these, the silicon compound D of the formula [16] is preferably the silicon compound A.

  In the water-repellent chemical solution for a silicon-based wafer, the concentration of the silicon compound B is preferably 0.01 to 20% by mass with respect to 100% by mass of the total amount of the silicon compound A. If the concentration is low, the effect of the silicon compound B is low, which is not preferable. Even if the concentration is excessively high, the effect of the silicon compound B is not improved, and conversely, there is a concern that the surface of the silicon wafer is eroded. Therefore, the concentration of the silicon compound B is particularly preferably 0.05 to 15% by mass with respect to 100% by mass of the total amount of the silicon compound A.

  In the water-repellent chemical solution for a silicon-based wafer, the silicon compound A and the silicon compound B may be diluted with an organic solvent. When the total amount of addition of silicon compound A and silicon compound B is 0.1 to 100% by mass with respect to 100% by mass of the total amount of the water-repellent chemical solution for silicon-based wafer, it is uniform on at least the concave surface of the irregular pattern. It is preferable because it is easy to form a water-repellent film. If it is less than 0.1 mass%, the protective effect of the uneven pattern tends to be insufficient. More preferably, it is 0.5-50 mass%, More preferably, it is 1-30 mass%. In addition, when the water-repellent chemical liquid for silicon-based wafers is diluted with an organic solvent, the organic solvent may contain a low boiling point, among the components contained in the water-repellent chemical liquid for silicon-based wafers It is important that the boiling point of the component having the largest amount by mass ratio exceeds 40 ° C. The boiling point is more preferably more than 60 ° C., and further preferably more than 80 ° C.

  Examples of the organic solvent that may be used for dilution in the water-repellent chemical solution for silicon-based wafers include, for example, hydrocarbons, esters, ethers, ketones, halogen-containing solvents, sulfoxide-based solvents, lactone-based solvents, and carbonate-based solvents. A solvent, an organic solvent such as a polyhydric alcohol derivative having no OH group, a nitrogen element-containing solvent having no N—H group, or a mixture thereof is preferably used. Among these, when hydrocarbons, esters, ethers, halogen-containing solvents, polyhydric alcohol derivatives having no OH group, or a mixture thereof are used, a water-repellent coating is formed on the surface of the concavo-convex pattern. It is more preferable because it can be formed in a short time.

  Examples of the hydrocarbons include toluene, benzene, xylene, hexane, heptane, and octane. Examples of the esters include ethyl acetate, propyl acetate, butyl acetate, and ethyl acetoacetate, and the ether. Examples of such classes include diethyl ether, dipropyl ether, dibutyl ether, tetrahydrofuran, dioxane and the like, and examples of the ketones include acetone, acetylacetone, methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, cyclohexanone, isophorone, and the like. Examples of the halogen-containing solvent include perfluorocarbons such as perfluorooctane, perfluorononane, perfluorocyclopentane, perfluorocyclohexane, hexafluorobenzene, 1, 1, 1, Hydrofluorocarbons such as 3-pentafluorobutane, octafluorocyclopentane, 2,3-dihydrodecafluoropentane, Zeolora H (manufactured by Nippon Zeon), methyl perfluoroisobutyl ether, methyl perfluorobutyl ether, ethyl perfluorobutyl ether, Hydrofluoroethers such as ethyl perfluoroisobutyl ether, Asahiklin AE-3000 (manufactured by Asahi Glass), Novec7100, Novec7200, Novec7300, and Novec7600 (all from 3M), chlorocarbons such as tetrachloromethane, hydrochlorocarbons such as chloroform, Chlorofluorocarbons such as dichlorodifluoromethane, 1,1-dichloro-2,2,3,3,3-pentafluoropropaprop 1,3-dichloro-1,1,2,2,3-pentafluoropropane, 1-chloro-3,3,3-trifluoropropene, 1,2-dichloro-3,3,3-trifluoropropene Examples of the sulfoxide solvent include dimethyl sulfoxide, and examples of the lactone solvent include γ-butyrolactone, γ-valerolactone, and the like. , Γ-hexanolactone, γ-heptanolactone, γ-octanolactone, γ-nonanolactone, γ-decanolactone, γ-undecanolactone, γ-dodecanolactone, δ-valerolactone, δ-hexanolactone, δ-octanolactone, δ-nonanolactone, δ-decanolactone, δ-undecanolactone, δ-dodecanolactone, Examples of carbonate solvents include dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, propylene carbonate, etc., and examples of the polyhydric alcohol derivatives that do not have an OH group include ε-hexanolactone. Is ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol diacetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol diethyl Ether, diethylene glycol butyl ester 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 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 methyl propyl ether, dipropylene glycol diethyl ether 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, Examples of the nitrogen element-containing solvent having no NH group include N, N-dimethylformamide, such as trapropylene glycol diacetate, butylene glycol dimethyl ether, butylene glycol monomethyl ether acetate, butylene glycol diacetate, and glycerin triacetate. N, N-dimethylacetamide, N-methyl-2-pyrrolidone, diethylamine, triethylamine, pyridine and the like.

  In addition, if a non-combustible solvent is used for a part or all of the solvent, the water-repellent chemical solution for silicon-based wafers becomes non-flammable or has a high flash point, so that the water-repellent chemical solution for silicon-based wafers is used. This is preferable because the risk of Many halogen-containing solvents are nonflammable, and the nonflammable halogen-containing solvent can be suitably used as a nonflammable organic solvent.

  In addition, it is preferable to use a solvent having a flash point exceeding 70 ° C. as the solvent from the viewpoint of safety in the fire service law.

  According to “International Harmonized System for Classification and Labeling of Chemicals; GHS”, a solvent having a flash point of 93 ° C. or lower is defined as “flammable liquid”. Therefore, even if it is not a nonflammable solvent, if a solvent having a flash point exceeding 93 ° C. is used as the solvent, the flash point of the water repellent chemical solution tends to exceed 93 ° C., and the chemical solution corresponds to “flammable liquid”. Since it becomes difficult, it is more preferable from the viewpoint of safety.

  Also, among lactone solvents, carbonate solvents, and polyhydric alcohol derivatives that do not have an OH group, many of them have high flash points, so the risk of water-repellent chemicals for silicon wafers can be reduced. preferable. From the viewpoint of safety, specifically, γ-butyrolactone, γ-valerolactone, γ-hexanolactone, γ-heptanolactone, γ-octanolactone, and γ-nonanolactone having a flash point exceeding 70 ° C. , Γ-decanolactone, γ-undecanolactone, γ-dodecanolactone, δ-valerolactone, δ-hexanolactone, δ-octanolactone, δ-nonanolactone, δ-decanolactone, δ-undecanolactone, δ- Dodecanolactone, ε-hexanolactone, 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 glyco Rudibutyl 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 Rudibutyl ether, tetraethylene glycol monomethyl ether acetate, tetraethylene glycol monoethyl ether acetate, tetraethylene glycol monobutyl ether acetate, tetraethylene glycol diacetate, propylene glycol diacetate, dipropylene glycol methyl propyl 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, etc. Is more preferably used as the solvent, and the flash point exceeds 93 ° C., γ-butyrolactone, γ-hexanolactone, γ-heptanolactone, γ-octanolactone, γ-nonanolactone, γ-decanolactone, γ- Undecanolactone, γ-dodecanolactone, δ-valerolactone, δ-hexanolactone, δ-octanolactone, δ-nonanolactone, δ-decanolactone, -Undecanolactone, δ-dodecanolactone, ε-hexanolactone, propylene carbonate, ethylene glycol diacetate, diethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, diethylene glycol diacetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol Monobutyl ether acetate, 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 diacetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monobutyl ether acetate, tripropylene glycol dimethyl ether, Ripropylene 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 More preferably, acetate, tetrapropylene glycol diacetate, butylene glycol diacetate, glycerin triacetate or the like is used as the solvent.

  In the water-repellent chemical solution for silicon-based wafer, the total amount of moisture in the starting material is preferably 5000 ppm by mass or less with respect to the total amount of the starting material. When the total amount of moisture exceeds 5000 ppm by mass, the effect of the silicon compound A is reduced, and it becomes difficult to form the water-repellent coating in a short time. For this reason, the moisture content in the starting material of the water-repellent chemical solution for silicon-based wafers is preferably as small as possible, and is particularly preferably 1000 ppm by mass or less, and more preferably 500 ppm by mass or less. The water content in the starting material of the water-repellent chemical solution for silicon-based wafer may be 5 ppm by mass or more as long as it is within the above range.

  Hereinafter, the second method will be described. The water-repellent chemical solution for metal wafer contains at least one compound selected from the compounds represented by the general formulas [6] to [12] and a salt compound thereof and a solvent.

Examples of the hydrocarbon group represented by R ⁸ in the general formula [6] include an alkyl group, an alkylene group, or a group in which part or all of the hydrogens are substituted with fluorine.

Examples of the hydrocarbon group contained in R ⁹ of the general formula [6] include an alkyl group, an alkylene group, or a group in which part or all of the hydrogen elements are substituted with a fluorine element. . ^Further, -OR 22 ^{(R 22} has a carbon number of 1 to 18 hydrocarbon group) is preferably from. Further, it is preferable that the carbon number of R ²² is 1 to 8, particularly 1 to 4, since more excellent water repellency can be imparted. R ²² is preferably a linear alkyl group.

Examples of the phosphorus element-containing compound of the general formula [6] include CH ₃ P (O) (OH) ₂ , C ₂ H ₅ P (O) (OH) ₂ , and C ₃ H ₇ P (O) (OH ) ₂ , C ₄ H ₉ P (O) (OH) ₂ , C ₅ H ₁₁ P (O) (OH) ₂ , C ₆ H ₁₃ P (O) (OH) ₂ , C ₇ H ₁₅ P (O) (OH) ₂ , C ₈ H ₁₇ P (O) (OH) ₂ , C ₉ H ₁₉ P (O) (OH) ₂ , C ₁₀ H ₂₁ P (O) (OH) ₂ , C ₁₁ H ₂₃ P ( O) (OH) ₂ , C ₁₂ H ₂₅ P (O) (OH) ₂ , C ₁₃ H ₂₇ P (O) (OH) ₂ , C ₁₄ H ₂₉ P (O) (OH) ₂ , C ₁₅ H _{31 P (O) (OH) 2} , C 16 H 33 P (O) (OH) 2, C 17 H 35 P (O) (OH) 2, C 18 H 37 P (O) (OH _{2, C 6 H 5 P (} O) (OH) 2, CF 3 P (O) (OH) 2, C 2 F 5 P (O) (OH) 2, C 3 F 7 P (O) (OH) ₂ , C ₄ F ₉ P (O) (OH) ₂ , C ₅ F ₁₁ P (O) (OH) ₂ , C ₆ F ₁₃ P (O) (OH) ₂ , C ₇ F ₁₅ P (O) ( OH) ₂ , C ₈ F ₁₇ P (O) (OH) ₂ , CF ₃ C ₂ H ₄ P (O) (OH) ₂ , C ₂ F ₅ C ₂ H ₄ P (O) (OH) ₂ , C _{3 F 7 C 2 H 4 P} (O) (OH) 2, C 4 F 9 C 2 H 4 P (O) (OH) 2, C 5 F 11 C 2 H 4 P (O) (OH) 2, _{C 6 F 13 C 2 H 4} P (O) (OH) 2, C 7 F 15 C 2 H 4 P (O) (OH) 2, C 8 F 17 C 2 H 4 P (O) (OH) 2 Or the above compound -P (O) (OH) ₂ group, -P (O) (OH) OCH ₃ group, -P (O) (OH) OC ₂ H ₅ group, -P (O) (OCH ₃ ) ₂ group, _{-P (O) (OC 2 H} 5) obtained by replacing the ₂ groups, and the like.

Furthermore, since the phosphorus element-containing compound of the general formula [6] can impart more excellent water repellency, it is preferable that g of the general formula [6] is 1 or 2, and further, g is 2. A compound represented by the following general formula [17] is preferable.
R ²³ —P (═O) — (OH) ₂ [17]
(In the formula [17], R ²³ is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements.)

R ^{8 in the} general formula [6] and R ^{23 in the} general formula [17] are, for example, an alkyl group, a phenyl group, a phenyl group in which a hydrogen element is substituted with an alkyl group, a naphthyl group, and a carbonization thereof. Examples include one in which part or all of the hydrogen groups are replaced with fluorine elements.

Further, R ^{8 in the} general formula [6] and R ^{23 in the} general formula [17] have 2 to 16 carbon atoms, particularly 4 to 14 carbon atoms, and more preferably 6 to 14 carbon dioxide, which has more excellent water repellency. Since it can provide, it is preferable. The hydrocarbon group in which some or all of the hydrogen elements may be replaced with fluorine elements is preferably an alkyl group, and particularly preferably a linear alkyl group. When the hydrocarbon group is a linear alkyl group, when the water-repellent film is formed, R ⁸ and R ²³ which are hydrophobic portions of the phosphorus element-containing compound represented by the general formulas [6] and [17] Since it becomes easy to line up in the direction perpendicular to the surface of the water repellent coating, the effect of imparting water repellency is further enhanced, which is more preferable. Further, R ⁸ and R ²³ are preferably a hydrocarbon group in which some or all of the hydrogen elements are replaced with fluorine elements because they can impart better water repellency.

  The phosphorus element-containing compound may be present as a salt of the general formula [6] or [17]. Examples of the salt include ammonium salt and amine salt.

In addition, R ^{10 of} the general formula [7], R ^{11 of} the general formula [8], R ^{14 of} the general formula [9], R ^{15 of} the general formula [10], R ^{16 of the} general formula [11], and R ¹⁷ and R ^{18 in} the general formula [12] are preferably monovalent hydrocarbon groups having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements, and C _m H _{2m + 1} (m = 1-18), C _n F _{2n + 1} CH ₂ CH ₂ (n = 1-8), C _r F _{2r + 1} CH ₂ (r = 1-8), C _s F _{2s + 1} (s = 1-8) ) Is preferred.

Examples of the compound represented by the general formula [7] include CH ₃ COCl, C ₂ H ₅ COCl, C ₃ H ₇ COCl, C ₄ H ₉ COCl, C ₅ H ₁₁ COCl, C ₆ H ₁₃ COCl, _{C 7 H 15 COCl, C 8} H 17 COCl, C 9 H 19 COCl, C 10 H 21 COCl, C 11 H 23 COCl, C 12 H 25 COCl, C 13 H 27 COCl, C 14 H 29 COCl, C 15 H ₃₁ COCl, C ₁₆ H ₃₃ COCl, C ₁₇ H ₃₅ COCl, C ₁₈ H ₃₇ COCl, C ₆ H ₅ COCl, CF ₃ COCl, C ₂ F ₅ COCl, C ₃ F ₇ COCl, C ₄ F ₉ COCl, _{C 5 F 11 COCl, C 6} F 13 COCl, C 7 F 15 COCl, C 8 F 17 COCl or, The these of -Cl groups, -F group, -Br group, the compound was replaced by -I group and the like.

Among the above-mentioned compounds, particularly preferred are C ₈ H ₁₇ COCl, C ₉ H ₁₉ in view of the affinity for a substance containing a metal element and the effect of imparting water repellency to the surface of the metal wafer. _{COCl, C 10 H 21 COCl,} C 11 H 23 COCl, C 12 H 25 COCl, C 13 H 27 COCl, C 14 H 29 COCl, C 15 H 31 COCl, C 16 H 33 COCl, C 17 H 35 COCl, _{C 18 H 37 COCl, C 4} F 9 COCl, C 5 F 11 COCl, C 6 F 13 COCl, C 7 F 15 COCl, include C ₈ F 17 COCl like.

Examples of the compound represented by the general formula [8] include C ₅ H ₁₁ NH ₂ , C ₆ H ₁₃ NH ₂ , C ₇ H ₁₅ NH ₂ , C ₈ H ₁₇ NH ₂ , and C ₉ H ₁₉ NH _2. C ₁₀ H ₂₁ NH ₂ , C ₁₁ H ₂₃ NH ₂ , C ₁₂ H ₂₅ NH ₂ , C ₁₃ H ₂₇ NH ₂ , C ₁₄ H ₂₉ NH ₂ , C ₁₅ H ₃₁ NH ₂ , C ₁₆ H ₃₃ NH ₂ , _{C 17 H 35 NH 2, C} 18 H 37 NH 2, CF 3 NH 2, CF 3 C 2 H 4 NH 2, C 2 F 5 NH 2, C 2 F 5 C 2 H 4 NH 2, C 3 F 7 _{NH 2, C 3 F 7 C} 2 H 4 NH 2, C 4 F 9 NH 2, C 4 F 9 C 2 H 4 NH 2, C 4 F 9 CH 2 NH 2, C 5 F 11 NH 2, C 5 F ₁₁ C ₂ H ₄ NH ₂ , C ₅ F _{11 CH 2 NH 2, C 6 F} 13 NH 2, C 6 F 13 C 2 H 4 NH 2, C 6 F 13 CH 2 NH 2, C 7 F 15 NH 2, C 7 F 15 C 2 H 4 NH 2, _{C 7 F 15 CH 2 NH 2} , C 8 F 17 NH 2, C 8 F 17 C 2 H 4 NH 2, C 8 F 17 CH 2 NH 2, C 4 F 7 H 2 NH 2, C 6 F 11 H ₂ NH ₂ , C ₈ F ₁₅ H ₂ NH ₂ , (C ₃ H ₇ ) ₂ NH, (C ₄ H ₉ ) ₂ NH, (C ₅ H ₁₁ ) ₂ NH, (C ₆ H ₁₃ ) ₂ NH, ( _{C 7 H 15) 2 NH,} (C 8 H 17) 2 NH, (C 9 H 19) 2 NH, (C 10 H 21) 2 NH, (C 11 H 23) 2 NH, (C 12 H 25) ₂ NH, (C ₁₃ H ₂₇ ) ₂ NH, (C ₁₄ H ₂₉ ) ₂ NH, (C ₁₅ H ₃₁ ) ₂ NH, (C ₁₆ H ₃₃ ) ₂ NH, (C ₁₇ H ₃₅ ) ₂ NH, (C ₁₈ H ₃₇ ) ₂ NH, (CF ₃ ) ₂ NH, (C ₂ F ₅ ) ₂ NH, (C ₃ F ₇ ) ₂ NH, (C ₄ F ₉ ) ₂ NH, (C ₅ F ₁₁ ) ₂ NH, (C ₆ F ₁₃ ) ₂ NH, (C ₇ F ₁₅ ) ₂ NH, (C ₈ F ₁₇ ) ₂ NH, (C ₄ F ₇ H ₂ ) ₂ NH, (C ₆ F ₁₁ H ₂ ) ₂ NH, (C ₈ F ₁₅ H ₂ ) ₂ NH, (C ₂ H ₅ ) ₃ N, (C _{3 H 7) 3 N, (} C 4 H 9) 3 N, (C 5 H 11) 3 N, (C 6 H 13) 3 N, (C 7 H 15) 3 N, (C 8 H 17) 3 N, (C ₉ H ₁₉ ) ₃ N, (C ₁₀ H ₂₁ ) ₃ N, (C ₁₁ H ₂₃ ) ₃ N, (C ₁₂ H ₂₅ ) ₃ N, ( _{C 13 H 27) 3 N,} (C 14 H 29) 3 N, (C 15 H 31) 3 N, (C 16 H 33) 3 N, (C 17 H 35) 3 N, (C 18 H 37) ₃ N, (CF ₃ ) ₃ N, (C ₂ F ₅ ) ₃ N, (C ₃ F ₇ ) ₃ N, (C ₄ F ₉ ) ₃ N, (C ₅ F ₁₁ ) ₃ N, (C ₆ F ₁₃ ) ₃ N, (C ₇ F ₁₅ ) ₃ N, (C ₈ F ₁₇ ) ₃ N, (C ₄ F ₇ H ₂ ) ₃ N, (C ₆ F ₁₁ H ₂ ) ₃ N, (C ₈ F ₁₅ H ₂ ) ₃ N, (C ₅ H ₁₁ ) (CH ₃ ) NH, (C ₆ H ₁₃ ) (CH ₃ ) NH, (C ₇ H ₁₅ ) (CH ₃ ) NH, (C ₈ H ₁₇ ) (CH ₃ ) NH, (C ₉ H ₁₉ ) (CH ₃ ) NH, (C ₁₀ H ₂₁ ) (CH ₃ ) NH, (C ₁₁ H ₂₃ ) (CH ₃ ) NH, (C _{12 H 25) (CH 3)} NH, (C 13 H 27) (CH 3) NH, (C 14 H 29) (CH 3) NH, (C 15 H 31) (CH 3) NH, (C 16 H ₃₃ ) (CH ₃ ) NH, (C ₁₇ H ₃₅ ) (CH ₃ ) NH, (C ₁₈ H ₃₇ ) (CH ₃ ) NH, (CF ₃ ) (CH ₃ ) NH, (C ₂ F ₅ ) (CH ₃ ) NH, (C ₃ F ₇ ) (CH ₃ ) NH, (C ₄ F ₉ ) (CH ₃ ) NH, (C ₅ F ₁₁ ) (CH ₃ ) NH, (C ₆ F ₁₃ ) (CH ₃ ) _{NH, (C 7 F 15)} (CH 3) NH, (C 8 F 17) (CH 3) NH, (C 3 H 7) (CH 3) 2 N, (C 4 H 9) (CH 3) 2 N, (C ₅ H ₁₁ ) (CH ₃ ) ₂ N, (C ₆ H ₁₃ ) (CH ₃ ) ₂ N, (C ₇ H ₁₅ ) (C H ₃ ) ₂ N, (C ₈ H ₁₇ ) (CH ₃ ) ₂ N, (C ₉ H ₁₉ ) (CH ₃ ) ₂ N, (C ₁₀ H ₂₁ ) (CH ₃ ) ₂ N, (C ₁₁ H ₂₃ ) (CH ₃ ) ₂ N, (C ₁₂ H ₂₅ ) (CH ₃ ) ₂ N, (C ₁₃ H ₂₇ ) (CH ₃ ) ₂ N, (C ₁₄ H ₂₉ ) (CH ₃ ) ₂ N, (C _{15 H 31) (CH 3) 2} N, (C 16 H 33) (CH 3) 2 N, (C 17 H 35) (CH 3) 2 N, (C 18 H 37) (CH 3) 2 N, ( _{CF 3) (CH 3) 2} N, (C 2 F 5) (CH 3) 2 N, (C 3 F 7) (CH 3) 2 N, (C 4 F 9) (CH 3) 2 N, ( C ₅ F ₁₁ ) (CH ₃ ) ₂ N, (C ₆ F ₁₃ ) (CH ₃ ) ₂ N, (C ₇ F ₁₅ ) (CH ₃ ) ₂ N, (C ₈ F ₁₇ ) (CH ₃ ) ₂ N and the like. The compound represented by the general formula [8] may be used as a salt. Examples of the salt include inorganic acid salts such as carbonates, hydrochlorides, sulfates and nitrates, and organic acid salts such as acetates, propionates, butyrate and phthalates.

Among the above-mentioned compounds, particularly preferred are C ₆ H ₁₃ NH ₂ and C ₇ H in view of the affinity for a substance containing a metallic element and the effect of imparting water repellency to the metallic wafer surface. _{15 NH 2, C 8 H 17} NH 2, C 9 H 19 NH 2, C 10 H 21 NH 2, C 11 H 23 NH 2, C 12 H 25 NH 2, C 13 H 27 NH 2, C 14 H 29 _{NH 2, C 15 H 31 NH} 2, C 16 H 33 NH 2, C 17 H 35 NH 2, C 18 H 37 NH 2, (C 4 H 9) 2 NH, (C 5 H 11) 2 NH, ( _{C 6 H 13) 2 NH,} (C 7 H 15) 2 NH, (C 8 H 17) 2 NH, (C 9 H 19) 2 NH, (C 10 H 21) 2 NH, (C 11 H 23) _{2 NH, (C} 12 _{H 2 ) 2 NH, (C 13 H} 27) 2 NH, (C 14 H 29) 2 NH, (C 15 H 31) 2 NH, (C 16 H 33) 2 NH, (C 17 H 35) 2 NH, ( _{C 18 H 37) 2 NH,} (C 4 H 9) 3 N, (C 5 H 11) 3 N, (C 6 H 13) 3 N, (C 7 H 15) 3 N, (C 8 H 17) ₃ N, (C ₉ H ₁₉ ) ₃ N, (C ₁₀ H ₂₁ ) ₃ N, (C ₁₁ H ₂₃ ) ₃ N, (C ₁₂ H ₂₅ ) ₃ N, (C ₁₃ H ₂₇ ) ₃ N, (C ₁₄ H ₂₉ ) ₃ N, (C ₁₅ H ₃₁ ) ₃ N, (C ₁₆ H ₃₃ ) ₃ N, (C ₁₇ H ₃₅ ) ₃ N, (C ₁₈ H ₃₇ ) ₃ N, (C ₅ H ₁₁ ) ( CH ₃ ) NH, (C ₆ H ₁₃ ) (CH ₃ ) NH, (C ₇ H ₁₅ ) (CH ₃ ) NH, (C ₈ H ₁₇ ) (CH ₃ ) NH, (C ₉ H ₁₉ ) (CH ₃ ) NH, (C ₁₀ H ₂₁ ) (CH ₃ ) NH, (C ₁₁ H ₂₃ ) (CH ₃ ) NH, (C ₁₂ H ₂₅ ) (CH ₃ ) NH, (C ₁₃ H ₂₇ ) (CH ₃ ) NH, (C ₁₄ H ₂₉ ) (CH ₃ ) NH, (C ₁₅ H ₃₁ ) (CH ₃ ) NH, (C ₁₆ H ₃₃ ) ( _{CH 3) NH, (C 17} H 35) (CH 3) NH, (C 18 H 37) (CH 3) NH, (C 4 H 9) (CH 3) 2 N, (C 5 H 11) (CH _{3) 2 N, (C 6} H 13) (CH 3) 2 N, (C 7 H 15) (CH 3) 2 N, (C 8 H 17) (CH 3) 2 N, (C 9 H 19) _{(CH 3) 2 N, (} C 10 H 21) (CH 3) 2 N, (C 11 H 23) (CH 3) 2 _{, (C 12 H 25) (} CH 3) 2 N, (C 13 H 27) (CH 3) 2 N, (C 14 H 29) (CH 3) 2 N, (C 15 H 31) (CH 3) _{2 N, (C 16 H 33} ) (CH 3) 2 N, (C 17 H 35) (CH 3) 2 N, (C 18 H 37) (CH 3) 2 N, C 4 F 9 NH 2, C ₄ F ₉ C ₂ H ₄ NH ₂ , C ₄ F ₉ CH ₂ NH ₂ , C ₅ F ₁₁ NH ₂ , C ₅ F ₁₁ C ₂ H ₄ NH ₂ , C ₅ F ₁₁ CH ₂ NH ₂ , C ₆ F _{13 NH 2, C 6 F 13 C} 2 H 4 NH 2, C 6 F 13 CH 2 NH 2, C 7 F 15 NH 2, C 7 F 15 C 2 H 4 NH 2, C 7 F 15 CH 2 NH 2, _{C 8 F 17 NH 2, C} 8 F 17 C 2 H 4 NH 2, C 8 F 17 CH Compounds such as NH ₂ and the like.

Examples of the compound represented by the general formula [9] include C ₅ H ₁₁ COOH, C ₆ H ₁₃ COOH, C ₇ H ₁₅ COOH, C ₈ H ₁₇ COOH, C ₉ H ₁₉ COOH, and C ₁₀ H _{21. COOH, C 11 H 23 COOH,} C 12 H 25 COOH, C 13 H 27 COOH, C 14 H 29 COOH, C 15 H 31 COOH, C 16 H 33 COOH, C 17 H 35 COOH, C 18 H 37 COOH, A compound such as C ₆ H ₅ COOH, C ₅ F ₁₁ COOH, C ₆ F ₁₃ COOH, C ₇ F ₁₅ COOH, C ₈ F ₁₇ COOH, or the —COOH group of the compound is replaced with —COOCH ₃ group, —COOC ₃ group, ₂ H ₅ group, -COOC ₆ H ₅ group, -COSH group, and compounds obtained by replacing the ₃ groups -COSCH etc.

Among the above-mentioned compounds, particularly preferred are C ₅ H ₁₁ COOH, C ₆ H ₁₃ in consideration of the affinity for a substance containing a metal element and the effect of imparting water repellency to the surface of the metal wafer. _{COOH, C 7 H 15 COOH,} C 8 H 17 COOH, C 9 H 19 COOH, C 10 H 21 COOH, C 11 H 23 COOH, C 12 H 25 COOH, C 13 H 27 COOH, C 14 H 29 COOH, C ₁₅ H ₃₁ COOH, C ₁₆ H ₃₃ COOH, C ₁₇ H ₃₅ COOH, C ₁₈ H ₃₇ COOH, or the —COOH group of the compound is replaced with —COOCH ₃ group, —COOC ₂ H ₅ group, —COOC ₆ H Examples thereof include compounds in which ₅ groups, -COSH group, and -COSCH ₃ group are substituted.

Examples of the compound represented by the general formula [10] include C ₂ H ₅ NCO, C ₃ H ₇ NCO, C ₄ H ₉ NCO, C ₅ H ₁₁ NCO, C ₆ H ₁₃ NCO, and C ₇ H _15. NCO, C ₈ H ₁₇ NCO, C ₉ H ₁₉ NCO, C ₁₀ H ₂₁ NCO, C ₁₁ H ₂₃ NCO, C ₁₂ H ₂₅ NCO, C ₁₃ H ₂₇ NCO, C ₁₄ H ₂₉ NCO, C ₁₅ H ₃₁ NCO, C ₁₆ H ₃₃ NCO, C ₁₇ H ₃₅ NCO, C ₁₈ H ₃₇ NCO, CF ₃ NCO, CF ₃ CH ₂ NCO, CF ₃ C ₂ H ₄ NCO, C ₂ F ₅ NCO, C ₂ F ₅ CH ₂ NCO, _{C 2 F 5 C 2 H 4} NCO, C 3 F 7 NCO, C 3 F 7 CH 2 NCO, C 3 F 7 C 2 H 4 NCO, C 4 F 9 NCO, C 4 F 9 CH 2 N _{O, C 4 F 9 C 2} H 4 NCO, C 5 F 11 NCO, C 5 F 11 CH 2 NCO, C 5 F 11 C 2 H 4 NCO, C 6 F 13 NCO, C 6 F 13 CH 2 NCO, C ₆ F ₁₃ C ₂ H ₄ NCO, C ₇ F ₁₅ NCO, C ₇ F ₁₅ CH ₂ NCO, C ₇ F ₁₅ C ₂ H ₄ NCO, C ₈ F ₁₇ NCO, C ₈ F ₁₇ CH ₂ NCO, C ₈ F ₁₇ C ₂ H ₄ NCO, C ₂ H ₄ (NCO) ₂ , C ₃ H ₆ (NCO) ₂ , C ₄ H ₈ (NCO) ₂ , C ₅ H ₁₀ (NCO) ₂ , C ₆ H ₁₂ (NCO ) ₂ , C ₇ H ₁₄ (NCO) ₂ , C ₈ H ₁₆ (NCO) ₂ , C ₉ H ₁₈ (NCO) ₂ , C ₁₀ H ₂₀ (NCO) ₂ , C ₁₁ H ₂₂ (NCO) ₂ , C ₁₂ H _{24 (NCO)} 2, C _{3 H 26 (NCO) 2,} C 14 H 28 (NCO) 2, C 15 H 30 (NCO) 2, C 16 H 32 (NCO) 2, C 17 H 34 (NCO) 2, C 18 H 36 (NCO ) ₂ , (NCO) C ₂ H ₄ NCO, (NCO) C ₃ H ₆ NCO, (NCO) C ₄ H ₈ NCO, (NCO) C ₅ H ₁₀ NCO, (NCO) C ₆ H ₁₂ NCO, (NCO) ) C ₇ H ₁₄ NCO, (NCO) C ₈ H ₁₆ NCO, (NCO) C ₉ H ₁₈ NCO, (NCO) C ₁₀ H ₂₀ NCO, (NCO) C ₁₁ H ₂₂ NCO, (NCO) C ₁₂ H _{24 NCO, (NCO) C 13 H} 26 NCO, (NCO) C 14 H 28 NCO, (NCO) C 15 H 30 NCO, (NCO) C 16 H 32 NCO, (NCO) C 17 H 3 _{NCO, (NCO) C 18 H} 36 NCO, C 2 H 3 (NCO) 3, C 3 H 5 (NCO) 3, C 4 H 7 (NCO) 3, C 5 H 9 (NCO) 3, C 6 H ₁₁ (NCO) ₃ , C ₇ H ₁₃ (NCO) ₃ , C ₈ H ₁₅ (NCO) ₃ , C ₉ H ₁₇ (NCO) ₃ , C ₁₀ H ₁₉ (NCO) ₃ , C ₁₁ H ₂₁ (NCO) _{3 , C 12 H 23 (NCO)} 3, C 13 H 25 (NCO) 3, C 14 H 27 (NCO) 3, C 15 H 29 (NCO) 3, C 16 H 31 (NCO) 3, C 17 H 33 (NCO) ₃ , C ₁₈ H ₃₅ (NCO) ₃ , C (NCO) ₄ , (NCO) ₂ C ₂ H ₂ (NCO) ₂ , (NCO) ₂ C ₃ H ₄ (NCO) ₂ , (NCO) _{2 C 4 H 6 (NCO) 2} , ( _{CO) 2 C 5 H 8 (} NCO) 2, (NCO) 2 C 6 H 10 (NCO) 2, (NCO) 2 C 7 H 12 (NCO) 2, (NCO) 2 C 8 H 14 (NCO) 2 , (NCO) ₂ C ₉ H ₁₆ (NCO) ₂ , (NCO) ₂ C ₁₀ H ₁₈ (NCO) ₂ , (NCO) ₂ C ₁₁ H ₂₀ (NCO) ₂ , (NCO) ₂ C ₁₂ H ₂₂ (NCO) ) ₂ , (NCO) ₂ C ₁₃ H ₂₄ (NCO) ₂ , (NCO) ₂ C ₁₄ H ₂₆ (NCO) ₂ , (NCO) ₂ C ₁₅ H ₂₈ (NCO) ₂ , (NCO) ₂ C ₁₆ H _{30 (NCO) 2, (NCO)} 2 C 17 H 32 (NCO) 2, (NCO) 2 C 18 H 34 (NCO) isocyanate compounds such as _2, or isocyanate of the isocyanate compound The (-NCO group), -SH group, -CHO group, -CONHOH group, imidazoline ring (the following formulas [18]) Compound was replaced by a ring structure containing a nitrogen element such like.

Among the above-mentioned compounds, particularly preferred are C ₄ H ₉ NCO, C ₅ H ₁₁ in view of the affinity for a substance containing a metal element and the effect of imparting water repellency to the metal wafer surface. NCO, C ₆ H ₁₃ NCO, C ₇ H ₁₅ NCO, C ₈ H ₁₇ NCO, C ₉ H ₁₉ NCO, C ₁₀ H ₂₁ NCO, C ₁₁ H ₂₃ NCO, C ₁₂ H ₂₅ NCO, C ₁₃ H ₂₇ NCO, _{C 14 H 29 NCO, C 15} H 31 NCO, C 16 H 33 NCO, C 17 H 35 NCO, C 18 H 37 NCO, C 3 F 7 CH 2 NCO, C 3 F 7 C 2 H 4 NCO, C 4 _{F 9 NCO, C 4 F 9} CH 2 NCO, C 4 F 9 C 2 H 4 NCO, C 5 F 11 NCO, C 5 F 11 CH 2 NCO, C 5 F 11 C 2 H 4 _{CO, C 6 F 13 NCO,} C 6 F 13 CH 2 NCO, C 6 F 13 C 2 H 4 NCO, C 7 F 15 NCO, C 7 F 15 CH 2 NCO, C 7 F 15 C 2 H 4 NCO, _{C 8 F 17 NCO, C 8} F 17 CH 2 NCO, C 8 F 17 C 2 H 4 isocyanate compounds such as NCO, or an isocyanate group of the isocyanate compound (-NCO group), -SH, -CHO, , -CONHOH group, compounds substituted with a ring structure containing a nitrogen element such as an imidazoline ring, and the like.

Examples of the compound represented by the general formula [11] include C ₄ H ₄ S, CH ₃ C ₄ H ₃ S, C ₂ H ₅ C ₄ H ₃ S, C ₃ H ₇ C ₄ H ₃ S, _{C 4 H 9 C 4 H 3} S, C 5 H 11 C 4 H 3 S, C 6 H 13 C 4 H 3 S, C 7 H 15 C 4 H 3 S, C 8 H 17 C 4 H 3 S, _{C 9 H 19 C 4 H 3} S, C 10 H 21 C 4 H 3 S, C 11 H 23 C 4 H 3 S, C 12 H 25 C 4 H 3 S, C 13 H 27 C 4 H 3 S, _{C 14 H 29 C 4 H 3} S, C 15 H 31 C 4 H 3 S, C 16 H 33 C 4 H 3 S, C 17 H 35 C 4 H 3 S, C 18 H 37 C 4 H 3 S, _{C 3 H 3 NS, CH 3} C 3 H 2 NS, C 2 H 5 C 3 H 2 NS, C 3 H 7 C 3 H 2 NS, C 4 _{9 C 3 H 2 NS, C} 5 H 11 C 3 H 2 NS, C 6 H 13 C 3 H 2 NS, C 7 H 15 C 3 H 2 NS, C 8 H 17 C 3 H 2 NS, C 9 H ₁₉ C ₃ H ₂ NS, C ₁₀ H ₂₁ C ₃ H ₂ NS, C ₁₁ H ₂₃ C ₃ H ₂ NS, C ₁₂ H ₂₅ C ₃ H ₂ NS, C ₁₃ H ₂₇ C ₃ H ₂ NS, C ₁₄ H ₂₉ C ₃ H ₂ NS, C ₁₅ H ₃₁ C ₃ H ₂ NS, C ₁₆ H ₃₃ C ₃ H ₂ NS, C ₁₇ H ₃₅ C ₃ H ₂ NS, C ₁₈ H ₃₇ C ₃ H ₂ NS, etc. Can be mentioned. C ₄ H ₄ S represents thiophene, C ₄ H ₃ S represents a thiophene ring, C ₃ H ₃ NS represents a thiazole, and C ₃ H ₂ NS represents a thiazole ring.

Examples of the compound represented by the general formula [12] include CH ₃ COOCOCH ₃ , C ₂ H ₅ COOCOC ₂ H ₅ , C ₃ H ₇ COOCOC ₃ H ₇ , C ₄ H ₉ COOCOC ₄ H ₉ and C _{5. H 11 COOCOC 5 H 11, C} 6 H 13 COOCOC 6 H 13, C 7 H 15 COOCOC 7 H 15, C 8 H 17 COOCOC 8 H 17, C 9 H 19 COOCOC 9 H 19, C 10 H 21 COOCOC 10 H _{21, C 11 H 23 COOCOC 11} H 23, C 12 H 25 COOCOC 12 H 25, C 13 H 27 COOCOC 13 H 27, C 14 H 29 COOCOC 14 H 29, C 15 H 31 COOCOC 15 H 31, C 16 H ₃₃ COOCOC ₁₆ H ₃₃ , C ₁₇ H _{3 5 COOCOC 17 H 35, C 18} H 37 COOCOC 18 H 37, C 6 H 5 COOCOC 6 H 5, CF 3 COOCOCF 3, C 2 F 5 COOCOC 2 F 5, C 3 F 7 COOCOC 3 F 7, C 4 F ₉ COOCOC ₄ F ₉ , C ₅ F ₁₁ COOCOC ₅ F ₁₁ , C ₆ F ₁₃ COOCOC ₆ F ₁₃ , C ₇ F ₁₅ COOCOC ₇ F ₁₅ , C ₈ F ₁₇ COOCOC ₈ F _{17 and the} like.

  Further, the compound selected from the compounds represented by the general formulas [6] to [12] and the salt compounds thereof has a HLB value of 0.001 to 10 according to the Griffin method, depending on the surface of the metal wafer. It is preferable because high water repellency can be imparted.

Further, the compound selected from the compounds represented by the general formulas [6] to [12] and a salt compound thereof is a compound represented by the following general formula [19] and a salt compound thereof, and a metal-based wafer surface It is preferable because higher water repellency can be imparted.
R ²⁴ -X ¹¹ [19]
[In Formula [19], X ¹¹ is selected from the group consisting of —P (O) (OH) ₂ , —NH ₂ group, —N═C═O group, —SH group, —CONHOH group, and imidazoline ring. At least one, and R ²⁴ is a hydrocarbon group having 4 to 18 carbon atoms or a C _t F _{2t + 1} — (CH ₂ ) _u — group (t = 4 to 8, u = 0 to 2). . ]

  Specifically, the solvent used in the second method of the present invention is the hydrocarbon, ester, ether, ketone, halogen-containing solvent, sulfoxide solvent, lactone solvent, carbonate described in the first method. Solvent, polyhydric alcohol derivative not having OH group, solvent similar to nitrogen element-containing solvent not having NH group, and water, methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol , Ethylene glycol, diethylene glycol, 1,3-propanediol, 1,2-propanediol, dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, triethylene glycol, triethylene glycol Propylene glycol, tetraethylene glycol, tetrapropylene Alcohols such as ethylene glycol, glycerin, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, tri Ethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monopropyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, tetraethylene glycol monopropyl ether, Raethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene Polyhydric alcohols with OH groups such as glycol monobutyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, tetrapropylene glycol monomethyl ether, butylene glycol monomethyl ether Invitation Nitrogen element-containing solvents having an N—H group such as a conductor and formamide are exemplified.

  Further, it is preferable to use a non-flammable solvent for a part or all of the solvent because the water-repellent chemical solution becomes non-flammable or the flash point becomes high and the risk of the chemical solution decreases. Many halogen-containing solvents are non-flammable, and non-flammable halogen-containing solvents can be suitably used as non-flammable solvents. Water can also be used as a non-flammable solvent.

  In addition, it is preferable to use a solvent having a flash point exceeding 70 ° C. as the solvent from the viewpoint of safety in the fire service law.

  According to “International Harmonized System for Classification and Labeling of Chemicals; GHS”, a solvent having a flash point of 93 ° C. or lower is defined as “flammable liquid”. Therefore, even if it is not a nonflammable solvent, if a solvent having a flash point exceeding 93 ° C. is used as the solvent, the flash point of the water repellent chemical solution tends to exceed 93 ° C., and the chemical solution corresponds to “flammable liquid”. Since it becomes difficult, it is more preferable from the viewpoint of safety.

  In addition, lactone solvents, carbonate solvents, and polyhydric alcohol derivatives are preferred because many of them have a high flash point, so that the risk of the water-repellent chemical solution can be reduced. From the viewpoint of safety, specifically, a solvent having a flash point exceeding 70 ° C. described in the first method, or ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, Dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, triethylene glycol, tripropylene glycol, tetraethylene glycol, tetrapropylene glycol, glycerin, diethylene glycol monomethyl ether, diethylene glycol monoethyl Ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol Monopropyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, tetraethylene glycol monopropyl ether, tetraethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, di Flash point of 70 ° C for propylene glycol monopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, tetrapropylene glycol monomethyl ether, etc. Over melting In addition, a solvent having a flash point exceeding 93 ° C. described in the first method, or ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, 1,2 -Butanediol, 1,3-butanediol, 1,4-butanediol, triethylene glycol, tripropylene glycol, tetraethylene glycol, tetrapropylene glycol, glycerin, diethylene glycol monomethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, tri Ethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monopropyl ether, triethylene glycol monobuty Ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, tetraethylene glycol monopropyl ether, tetraethylene glycol monobutyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tripropylene glycol A solvent having a flash point of more than 93 ° C., such as monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, tetrapropylene glycol monomethyl ether, is more preferable.

  Further, the concentration of at least one compound selected from the group consisting of the compounds represented by the general formulas [6] to [12] and a salt compound thereof in the water-repellent chemical solution for metal wafers is the metal wafer. It is preferable that it is 0.0005-2 mass% with respect to 100 mass% of total amounts of a chemical | medical solution. If it is less than 0.0005% by mass, the effect of imparting water repellency tends to be insufficient, and if it exceeds 2% by mass, it tends to be difficult to dissolve in a solvent. More preferably, it is 0.001-1 mass%, Most preferably, it is 0.0015-0.8 mass%. The water-repellent chemical solution for metal-based wafers may contain an organic solvent having a low boiling point. Among the components contained in the water-repellent chemical solution for metal-based wafers, the component having the largest amount by mass ratio. It is important that the boiling point is above 40 ° C. The boiling point is more preferably more than 60 ° C., and further preferably more than 80 ° C.

  In addition, as a solvent of the water-repellent chemical solution for metal-based wafers, an OH group is included among hydrocarbons, esters, ethers, ketones, and polyhydric alcohol derivatives, because it can provide more excellent water repellency. Those having no water, water, or a mixture thereof are preferred. Furthermore, in consideration of the displaceability with a cleaning liquid, particularly a cleaning liquid composed of an aqueous liquid, a derivative of a polyhydric alcohol having no OH group, water, or a mixture thereof is preferable.

  In the cleaning method of the present invention, the water-repellent chemical solution, that is, the water-repellent chemical solution for silicon-based wafers or the water-repellent chemical solution for metal-based wafers is set to 40 ° C. or higher. Is preferably 40 ° C. or higher. Although a solvent having a boiling point of less than 40 ° C. may be used, the other solvent having a boiling point of more than 40 ° C. is the component having the largest amount by mass ratio among the components contained in the water-repellent chemical liquid (hereinafter referred to as main component). It may be described as a solvent component). The main solvent component preferably has a boiling point of 50 ° C. or higher, more preferably 70 ° C. or higher.

  Moreover, the said water-repellent chemical | medical solution for silicon wafers may contain an additive etc. other than the silicon compound A represented by the said General formula [1], an acid or a base, and a solvent. Similarly, the water-repellent chemical solution for a metal-based wafer includes at least one compound selected from the group consisting of the compounds represented by the general formulas [6] to [12] and a salt compound thereof, and a solvent. , May contain additives and the like. Examples of the additive include oxidizing agents such as hydrogen peroxide and ozone, and surfactants. In addition, when a part of the concave / convex pattern of the wafer includes a material that does not form a water-repellent coating with the silicon compound A or the compounds represented by the general formulas [6] to [12], the material is repellent. You may add what can form an aqueous film. Further, in the water-repellent chemical solution for silicon-based wafer, other acid may be added for the purpose other than obtaining the silicon compound B.

  In the present invention, the cleaning method of the wafer is not particularly limited as long as the water-repellent chemical liquid or the cleaning liquid can be held in at least the concave portion of the concave / convex pattern of the wafer. As a wafer cleaning method, a wafer cleaning method represented by spin cleaning in which a wafer is cleaned one by one by supplying liquid to the vicinity of the rotation center while rotating the wafer while holding the wafer substantially horizontal, or a plurality of cleaning methods in the cleaning tank. One example is a batch system in which a single wafer is immersed and washed. The form of the water-repellent chemical liquid or cleaning liquid when supplying the water-repellent chemical liquid or cleaning liquid to at least the concave portion of the concave / convex pattern of the wafer is not particularly limited as long as it becomes a liquid when held in the concave portion. For example, there are liquid, vapor and the like.

  In the present invention, the wafer is not particularly limited as long as it has a concavo-convex pattern, for example, a wafer containing silicon element on the surface of the concave portion of the concavo-convex pattern, titanium, tungsten, aluminum, copper, tin, tantalum, and A wafer having at least one element of ruthenium is used.

  The wafer containing silicon element on the concave surface of the concave / convex pattern is formed, for example, by forming at least one component selected from silicon, silicon oxide, and silicon nitride on at least the concave surface of the wafer, or forming the concave / convex pattern. Sometimes, at least the surface of the recess is at least one component selected from silicon, silicon oxide, and silicon nitride. In addition, at least one component selected from silicon, silicon oxide, and silicon nitride is formed on at least a part of the concave surface of the wafer, or when the concave / convex pattern is formed, at least a part of the concave surface is silicon. , Silicon oxide, and silicon nitride may be used as at least one component. In this case, a water-repellent film is formed on at least one surface selected from silicon, silicon oxide, and silicon nitride present on at least a part of the concave surface by the water-repellent chemical solution for silicon-based wafers. Accordingly, the water repellent coating may be formed on at least a part of the concave surface of the wafer.

A wafer having at least one element of titanium, tungsten, aluminum, copper, tin, tantalum, and ruthenium on the surface of the concave portion of the concave / convex pattern is a silicon wafer, silicon and / or silicon oxide (SiO ₂ ). The surface of wafers, silicon carbide wafers, sapphire wafers, various compound semiconductor wafers, plastic wafers, and the like composed of a plurality of components containing tantalum, materials containing titanium elements such as titanium, titanium nitride, and titanium oxide, or tungsten A substance containing a tungsten element such as tungsten oxide, a substance containing an aluminum element such as aluminum or aluminum oxide, a substance containing a copper element such as copper or copper oxide, a substance containing a tin element such as tin or tin oxide, tantalum nitride, Substances containing tantalum element such as tantalum oxide Alternatively, a material coated with a layer containing a ruthenium element such as ruthenium or ruthenium oxide, or a multilayer film formed on a wafer, at least one of which is a layer containing a material containing the metal-based element, etc. For example, the concavo-convex pattern forming step is performed in a layer including a layer of a substance including the metal element. In addition, when the concavo-convex pattern is formed, at least a part of the surface of the concavo-convex pattern includes a material having at least one element among the metal-based elements.

  In addition, even on a wafer composed of a plurality of components including a substance having at least one element among the metal-based elements, the metal is formed on the surface of the substance having at least one element among the metal-based elements. A water-repellent coating can be formed with a water-repellent chemical solution for a wafer. The wafer composed of the plurality of components is a wafer in which a substance having at least one element among metal elements is formed on at least a part of the concave surface, or at least the concave surface when a concave / convex pattern is formed. A part of which becomes a substance having at least one element among metal-based elements is also included. In addition, it is the surface of the substance part which has at least 1 sort (s) of element in the said uneven | corrugated pattern that can form a water-repellent film with the water-repellent chemical solution for metal-based wafers of the present invention. Therefore, the water-repellent coating may be formed on at least a part of the concave surface of the metal wafer with the water-repellent chemical solution for metal wafer.

The cleaning method of the present invention is particularly preferably
(Step 1) A step of providing an aqueous liquid to the surface after making the wafer surface a surface having an uneven pattern, and holding the aqueous liquid in at least a recess of the uneven pattern;
(Step 2) A step of replacing the liquid held in at least the concave portion of the concave-convex pattern with a cleaning liquid containing 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C.,
(Step 3) A step of replacing the cleaning liquid with a water-repellent chemical solution and holding the chemical solution in at least the concave portion of the concave-convex pattern,
(Step 4) A step of removing liquid from the surface of the concavo-convex pattern by drying,
(Step 5) A step of removing the water-repellent film is included.

  First, as described in the above (Step 1), the aqueous liquid is held in at least the concave portion of the concave-convex pattern. Examples of acids that can be mixed with the aqueous liquid include inorganic acids and organic acids. Examples of inorganic acids include hydrofluoric acid, buffered hydrofluoric acid, sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid, etc. Examples of organic acids include methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid , Acetic acid, trifluoroacetic acid, pentafluoropropionic acid and the like. Examples of the alkali that may be mixed in the cleaning liquid include ammonia and choline. Examples of the oxidizing agent that may be mixed with the cleaning liquid include ozone and hydrogen peroxide.

  Next, as described in the above (Step 2), the liquid held in the concave portion is replaced with a cleaning liquid containing 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C. Note that the liquid held in the concave portion before the replacement may be the aqueous liquid or a rinsing liquid A described later.

  The cleaning liquid is preferably at least one liquid selected from the group consisting of an organic solvent, water, and an aqueous solution in which at least one of an organic solvent, an acid, an alkali, and an oxidizing agent is mixed in water.

  In addition, when preparing the said washing | cleaning liquid containing the organic solvent whose boiling point is less than 55 degreeC, the organic solvent whose boiling point is less than 55 degreeC, and the organic solvent whose boiling point is 55-200 degreeC are mixed, and the obtained mixture The cleaning liquid is prepared such that the liquid contains 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C. Moreover, when preparing the said washing | cleaning liquid containing the organic solvent whose boiling point exceeds 200 degreeC, the organic solvent whose boiling point exceeds 200 degreeC, and the organic solvent whose boiling point is 55-200 degreeC are mixed, and the mixture obtained The cleaning liquid is prepared such that the liquid contains 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C.

  The cleaning liquid is preferably an organic solvent, water, or a mixture of water and an organic solvent from the viewpoint of cleanliness. Furthermore, it is preferable that the cleaning liquid is an organic solvent because the water-repellent chemical liquid can be provided to the recess without being brought into contact with water. In particular, it is preferable that the organic solvent contains a water-soluble organic solvent (solubility with respect to 100 parts by mass of water is 5 parts by mass or more) because it can be easily replaced from an aqueous liquid.

  In addition, after the step (step 1) of holding the aqueous liquid in the concave portion, the aqueous liquid held in at least the concave portion of the concave / convex pattern may be referred to as a liquid different from the liquid (hereinafter referred to as rinse liquid A). ), The process may be shifted to the step of replacing with the cleaning liquid (step 2).

  A plurality of liquids may be substituted for the rinse liquid A. For example, the rinsing liquid A can be used after being substituted with water and further substituted with an organic solvent (preferably containing a water-soluble organic solvent).

  Next, as described in the above (Step 3), the water-repellent chemical solution is held in at least the concave portion of the concavo-convex pattern, and the water-repellent coating film is formed on the concave surface of the concave-convex pattern of the wafer by the water-repellent chemical solution. The temperature of the water-repellent chemical solution provided in the replacing step is 40 ° C. or higher and lower than the boiling point of the water-repellent chemical solution.

When the water-repellent coating is formed on the concave surface of the concave / convex pattern of the wafer with a water-repellent chemical solution, pattern collapse occurs when the contact angle is 50 to 130 ° when water is assumed to be retained on the surface. It is preferable because it is difficult. Further, the closer the contact angle is to 90 °, the smaller the capillary force acting on the recess and the more difficult the pattern collapse occurs, so 60-120 ° is particularly preferable, and 70-110 ° is more preferable. The capillary force is preferably 2.1 MN / m ² or less. It is preferable that the capillary force is 2.1 MN / m ² or less because pattern collapse hardly occurs. Also, when the capillary force is small, the collapse is further difficult to occur pattern, capillary force is particularly preferably 1.5Mn / ^{m 2} or less, more preferably 1.0 MN / ^{m 2} or less. Furthermore, it is ideal to adjust the contact angle with the liquid to around 90 ° so that the capillary force is as close as possible to 0.0 MN / m ² .

  Next, as described in the above (Step 4), a step of removing the liquid from the surface of the concavo-convex pattern by drying is performed. In this step, the liquid held on the uneven pattern surface is removed by drying. The drying is preferably performed by a known drying method such as a spin drying method, IPA (2-propanol) vapor drying, Marangoni drying, heat drying, air blowing drying, hot air drying, or vacuum drying.

  In addition, after the step (Step 3) of holding the water-repellent chemical liquid in at least the concave portion of the concavo-convex pattern, the water-repellent chemical liquid held in at least the concave portion of the concavo-convex pattern is a liquid different from the chemical liquid (hereinafter referred to as the rinse liquid B). After substituting (which may be described), the process may be transferred to a step of removing the liquid from the surface of the concavo-convex pattern by drying (step 4).

  Further, as the rinsing liquid B, a plurality of cleaning liquids may be substituted and used. For example, the rinsing liquid B can be used after being replaced with an organic solvent (preferably containing a water-soluble organic solvent) and then with an aqueous liquid.

  Examples of the rinsing liquid A and the rinsing liquid B include water, an organic solvent, a mixture of water and an organic solvent, a mixture of at least one of an acid, an alkali, and a surfactant, or a combination thereof. From the group consisting of the silicon compound A, the silicon compound A and an acid or base, and the compounds represented by the general formulas [6] to [12] and salts thereof, which may be used in the water-repellent chemical liquid. Examples include those in which at least one selected compound is added so as to have a concentration lower than that of the water-repellent chemical solution.

  Examples of the organic solvent that is one of the preferred examples of the cleaning liquid, the rinsing liquid A, and the rinsing liquid B include hydrocarbons, esters, ethers, ketones, halogen-containing solvents, sulfoxide solvents, Examples include alcohols, polyhydric alcohol derivatives, nitrogen element-containing solvents, and the like.

  Specific examples of the organic solvent include organic solvents that may be used for dilution in the water-repellent chemical solution for silicon-based wafers, and organic solvents that are used in the water-repellent chemical solution for metal-based wafers.

  When the liquid is removed from the surface of the concavo-convex pattern, the liquid held on the surface may be the water repellent chemical liquid, the rinse liquid B, and a mixture thereof. The liquid mixture containing the water-repellent chemical liquid may be a liquid in the middle of replacing the water-repellent chemical liquid with the rinse liquid B, or the water-repellent chemical liquid is mixed in advance with the rinse liquid B different from the water-repellent chemical liquid. A mixed solution obtained in this manner may be used. Further, after the liquid is once removed from the surface of the concave / convex pattern, the rinse liquid B or the mixed liquid may be held on the surface of the concave / convex pattern and then dried. When the liquid is removed from the surface of the concavo-convex pattern, the water-repellent coating is present on the surface of the concave portion, so that the capillary force applied to the concave portion is reduced and the pattern collapse hardly occurs.

  In addition, in the process (process 4) of removing a liquid from the uneven | corrugated pattern surface by drying, the liquid removed from the uneven | corrugated pattern surface is water, the said organic solvent, or those mixtures among the said rinse liquid B. It is preferable because the surface of the wafer hardly remains after drying. Further, an aqueous liquid, particularly water, is preferable because the contact angle θ with the liquid on the concave surface of the concave-convex pattern made water-repellent by the water-repellent chemical liquid is increased, and the capillary force P acting on the concave is reduced. .

  Note that the cleaning liquid, the rinsing liquid A, and the rinsing liquid B may also be held at a temperature of 10 ° C. or higher and lower than the boiling point of the liquid. For example, as the rinsing liquid A, a solution containing an acidic aqueous solution, particularly preferably an acidic aqueous solution and an organic solvent having a boiling point of 100 ° C. or higher is used, and when the temperature of the rinsing liquid A is increased near the boiling point of the rinsing liquid A, The water repellent coating is preferable because it can be easily formed in a short time.

  Next, as described in the above (Step 5), a step of removing the water-repellent coating is performed. When removing the water-repellent coating, it is effective to cut the C—C bond and C—F bond in the water-repellent coating. The method is not particularly limited as long as it can cut the bond, for example, irradiating the wafer surface with light, heating the wafer, exposing the wafer to ozone, irradiating the wafer surface with plasma, For example, corona discharge on the wafer surface may be mentioned.

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

  Further, when the water-repellent coating is removed by light irradiation, ozone is generated at the same time as the components of the water-repellent coating are decomposed by ultraviolet rays, and the components of the water-repellent coating are oxidized and volatilized by the ozone. Is particularly preferable. As this light source, a low-pressure mercury lamp or an excimer lamp is used. Further, the wafer may be heated while irradiating light.

  When the wafer is heated, the wafer is heated at 400 to 700 ° C, preferably 500 to 700 ° C. This heating time is preferably 0.5 to 60 minutes, preferably 1 to 30 minutes. In this process, ozone exposure, plasma irradiation, corona discharge, etc. may be used in combination. Further, light irradiation may be performed while heating the wafer.

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

  In the step of removing the water-repellent film on the wafer surface, the water-repellent film on the wafer surface can be efficiently removed by combining the light irradiation, heating, ozone exposure, plasma irradiation, corona discharge, and the like. .

Making the surface of the wafer a surface having a concavo-convex pattern is a technique that has been variously studied in other literatures and has already been established. Therefore, in the present invention, surface treatment of a wafer using the water-repellent chemical solution The evaluation was conducted mainly. Also, the following formula
P = 2 × γ × cos θ / S
(Where γ is the surface tension of the liquid held in the recess, θ is the contact angle between the surface of the recess and the liquid held in the recess, and S is the width of the recess). Greatly depends on the contact angle of the liquid held on the wafer surface, that is, the contact angle of the liquid droplet and the surface tension of the liquid. In the case of a liquid held in the concave portion 4 of the concave / convex pattern 2, the contact angle of the liquid droplet and the capillary force acting on the concave portion, which can be considered as equivalent to pattern collapse, have a correlation. The capillary force may be derived from the evaluation of the contact angle of the droplet of the water repellent coating 12. In the examples, water, which is a typical aqueous liquid, was used as the liquid.

  However, in the case of a wafer having a concavo-convex pattern on the surface, the contact angle of the water-repellent coating 12 itself formed on the concavo-convex pattern surface cannot be accurately evaluated.

  The contact angle of water droplets is evaluated by dropping several μl of water droplets on the sample (base material) surface as in JIS R 3257 “Test method for wettability of substrate glass surface”, and the angle between the water droplet and the substrate surface. It is made by measuring. However, in the case of a wafer having a pattern, the contact angle becomes very large. This is because a Wenzel effect and a Cassie effect occur, and the contact angle is affected by the surface shape (roughness) of the substrate, and the apparent contact angle of water droplets increases.

  Therefore, in this embodiment, the water-repellent chemical solution is applied to a wafer having a smooth surface, a water-repellent film is formed on the wafer surface, and the water-repellent film is formed on the surface of the wafer 1 on which the uneven pattern 2 is formed. Various evaluations were made considering the formed water-repellent coating 12. In this example, as a silicon wafer having a smooth surface, a “wafer with a thermal oxide film” having a smooth thermal oxide film layer on a smooth silicon wafer, a smooth wafer on a silicon wafer having a smooth surface. A “wafer with a silicon nitride film” having a silicon nitride layer was used. In addition, as a metal wafer with a smooth surface, a “wafer with a titanium nitride film” having a titanium nitride layer on a silicon wafer with a smooth surface, and a “wafer with a tungsten film” having a tungsten layer on a silicon wafer with a smooth surface. In addition, a “wafer with a ruthenium film” having a ruthenium layer on a silicon wafer having a smooth surface was used.

  In the cleaning method in which the liquid is supplied to the wafer while rotating the wafer, it is extremely difficult to strictly reproduce the replacement state from the cleaning liquid to the water-repellent chemical liquid.In this embodiment, the wafer immersed in the cleaning liquid is The substitution state was accurately reproduced by immersing in a water repellent chemical solution while the cleaning solution was held on the wafer surface. Moreover, the water-repellent state (water-repellent coating state) of the wafer when the degree of progress of substitution was changed was evaluated by changing the immersion time in the water-repellent chemical solution.

  Details are described below. In the following, a method for evaluating a wafer provided with a water-repellent chemical solution, preparation of the water-repellent chemical solution, and an evaluation result after providing the water-repellent chemical solution to a wafer will be described.

[Evaluation method of wafer provided with water repellent chemical]
The following evaluations (1) to (2) were performed as methods for evaluating a wafer provided with a water-repellent chemical solution.

(1) Contact angle evaluation of the water-repellent coating formed on the wafer surface About 2 μl of pure water is placed on the wafer surface on which the water-repellent coating is formed, and the angle between the water droplet and the wafer surface (contact angle) is measured as a contact angle meter. (Measured by Kyowa Interface Science: CA-X type). This measurement was performed at five locations on the wafer surface, and the average value was calculated.

(2) Evaluation of capillary force P was calculated using the following equation, and the capillary force (absolute value of P) was determined.
P = 2 × γ × cos θ / S
(Wherein γ is the surface tension of the liquid held in the recess, θ is the contact angle between the recess surface and the liquid held in the recess, and S is the width of the recess.)

In the present embodiment, as an example of the pattern shape, a line-and-space pattern wafer having a line width (recessed portion width) of 45 nm is assumed. In a pattern with a recess width of 45 nm, the pattern tends to collapse when the cleaning liquid is water when the gas-liquid interface passes through the irregular pattern, and the pattern tends not to collapse when 2-propanol is used. When the width of the recess is 45 nm and the wafer surface is silicon oxide, the capillary force is 0.98 MN / m ² when the cleaning liquid is 2-propanol (surface tension: 22 mN / m, contact angle with respect to the silicon oxide surface: 1 °). . On the other hand, the capillary force is 3.2 MN / m ^{2 in} water (surface tension: 72 mN / m, contact angle with silicon oxide: 2.5 °) having the largest surface tension among liquids excluding mercury. When the wafer surface is, for example, titanium nitride, tungsten, or ruthenium, the contact angle of 2-propanol with respect to the surface is 0.5 °, and the contact angle of water is also 2 °. The same is true for substances containing other titanium elements, tungsten elements, and ruthenium elements (eg, titanium, titanium oxide, tungsten oxide, ruthenium oxide, etc.). In the case of a wafer with a titanium nitride film, a wafer with a tungsten film, or a wafer with a ruthenium film having a recess width of 45 nm, the capillary force is 0.98 MN / m ² when the cleaning liquid is 2-propanol (surface tension: 22 mN / m). It becomes. On the other hand, the capillary force is 3.2 MN / m ^{2 in} water (surface tension: 72 mN / m) having the largest surface tension among liquids excluding mercury.

[Example 1-1]
(1) Cleaning a wafer with a cleaning solution A wafer with a smooth thermal oxide film (a silicon-based wafer having a 1 μm thick thermal oxide film layer on the surface) is immersed in a 1% by mass hydrofluoric acid aqueous solution at room temperature for 2 minutes, It was immersed in pure water for 1 minute and in 2-propanol (iPA; boiling point 82 ° C.) for 1 minute. Therefore, the cleaning liquid retained on the wafer surface after cleaning is iPA.

(2) Preparation of water-repellent chemical solution In this example, hexamethyldisilazane [(H ₃ C) ₃ Si—NH—Si (CH ₃ ) ₃ ] as silicon compound A; 5 g, trimethylsilyl trifluoroacetate as silicon compound B [(CH ₃ ) ₃ Si—OC (O) CF ₃ ]; 0.1 g and propylene glycol monomethyl ether acetate (PGMEA); 94.9 g as an organic solvent were mixed to obtain a water-repellent chemical solution. Of the components contained in the water-repellent chemical solution, the component having the largest amount by mass ratio is PGMEA, and its boiling point is 146 ° C.

(3) Replacing wafer surface cleaning liquid with water-repellent chemical liquid The water-repellent chemical liquid prepared in “(2) Preparation of water-repellent chemical liquid” was heated to 40 ° C. and prepared in “(1) Cleaning of wafer” above. The wafer with the thermal oxide film was immersed in the chemical solution for various times (5, 10, 20, 30, 40, 50, 60 sec), and the cleaning solution was replaced to form a water repellent coating. Thereafter, the wafer with the thermal oxide film was pulled up from the chemical solution and immersed in iPA for 60 seconds as a rinse solution, and then immersed in pure water for 60 seconds.
(4) Drying of wafer Finally, the wafer with the thermal oxide film was taken out from the pure water, air was blown and blown and dried to remove the pure water on the surface.

The obtained wafer with a thermal oxide film was evaluated in the manner described in the above-mentioned “Evaluation method of wafer provided with water-repellent chemical solution”, and the contact angle of the wafer with the thermal oxide film after the surface treatment was 75 ° or more and 80 °. The surface treatment time required for the above and 85 ° or more (that is, the capillary force is 0.8 MN / m ² or less, 0.6 MN / m ² or less, and 0.3 MN / m ² or less, respectively) (Replacement time) was examined. The results are shown in Table 1.

[Examples 1-2 to 1-10, Comparative Examples 1-1 to 1-5]
The temperature of the water repellent chemical solution used in Example 1-1, the cleaning solution before the water repellent treatment, and the solvent of the water repellent chemical solution were appropriately changed, and the surface treatment of the wafer with the thermal oxide film was performed and further evaluated. The results are shown in Table 1. DEGEA means diethylene glycol monoethyl ether acetate, and among the components contained in the water-repellent chemical solution using the solvent, the component having the largest amount by mass ratio is DEGEA, and its boiling point is 218 ° C. . PGDA means propylene glycol diacetate. Among the components contained in the water-repellent chemical solution using the solvent, the component having the largest amount by mass ratio is PGDA, and its boiling point is 190 ° C. PGMEA / DEE means a solvent in which PGMEA and diethyl ether (DEE; boiling point 35 ° C.) are mixed at a mass ratio of 90:10, and among the components contained in the water-repellent chemical solution using the mixed solvent, The component with the highest amount in ratio is PGMEA, which has a boiling point of 146 ° C. Similarly, PGMEA / DEGEEA means a solvent in which PGMEA and DEGEA are mixed at a mass ratio of 90:10. Among the components contained in the water-repellent chemical solution using the mixed solvent, the component having the largest amount by mass ratio. Is PGMEA and has a boiling point of 146 ° C. Similarly, DEGEA / PGMEA means a solvent in which DEGEA and PGMEA are mixed at a mass ratio of 90:10, and among the components contained in the cleaning liquid using the mixed solvent, the component having the largest amount by mass ratio is: DEGEA, whose boiling point is 218 ° C.

[Example 2-1]
As the silicon compound D, hexamethyldisilazane [(H ₃ C) ₃ Si—NH—Si (CH ₃ ) ₃ ]; 5 g, as the acid D, trifluoroacetic anhydride [{CF ₃ C (O)} ₂ O]; By mixing and reacting 0.1 g of PGMEA; 94.9 g as an organic solvent, a water repellent chemical solution containing trimethylsilyl trifluoroacetate as silicon compound B, hexamethyldisilazane as silicon compound A, and PGMEA as organic solvent is obtained. The same as Example 1-1, except for the above. Of the components contained in the water-repellent chemical solution, the component having the largest amount by mass ratio is PGMEA, and its boiling point is 146 ° C. Hexamethyldisilazane contained in the water-repellent chemical solution of this example is silicon compound D that was not consumed in the reaction for obtaining silicon compound B, and the component functions as silicon compound A. The results are shown in Table 2.

[Examples 2-2 to 2-6, Comparative Examples 2-1 to 2-4]
The temperature of the water repellent chemical solution used in Example 2-1, the cleaning solution before the water repellent treatment, and the solvent of the water repellent chemical solution were changed as appropriate, and the surface treatment of the wafer with the thermal oxide film was performed and further evaluated. The results are shown in Table 2.

[Example 3-1]
The procedure was the same as Example 2-1, except that the acid D was changed to trifluoroacetic acid [CF ₃ C (O) —OH]. In addition, among the components contained in the water-repellent chemical solution obtained in this example, the component having the largest amount by mass ratio is PGMEA, and its boiling point is 146 ° C. The results are shown in Table 3.

[Examples 3-2 to 3-6, Comparative Examples 3-1 to 3-4]
The temperature of the water-repellent chemical solution used in Example 3-1, the cleaning solution before the water-repellent treatment, and the solvent of the water-repellent chemical solution were appropriately changed, and the surface treatment of the wafer with the thermal oxide film was performed and further evaluated. The results are shown in Table 3.

[Example 4-1]
Example 3 was the same as Example 1-1 except that trimethylsilyldimethylamine [(CH ₃ ) ₃ Si—N (CH ₃ ) ₂ ] was used as silicon compound A, and silicon compound B was not used. In addition, among the components contained in the water-repellent chemical solution obtained in this example, the component having the largest amount by mass ratio is PGMEA, and its boiling point is 146 ° C. The results are shown in Table 4.

[Examples 4-2 to 4-4, Comparative examples 4-1 to 4-2]
The temperature of the water-repellent chemical solution used in Example 4-1 and the cleaning solution before the water-repellent treatment were appropriately changed, and the surface treatment of the wafer with the thermal oxide film was performed and further evaluated. The results are shown in Table 4.

[Example 5-1]
The same as Example 4-1 except that octyldimethyl (dimethylamino) silane [C ₈ H ₁₇ Si (CH ₃ ) ₂ —N (CH ₃ ) ₂ ] was used as the silicon compound A. In addition, among the components contained in the water-repellent chemical solution obtained in this example, the component having the largest amount by mass ratio is PGMEA, and its boiling point is 146 ° C. The results are shown in Table 5.

[Examples 5-2 to 5-8, Comparative examples 5-1 to 5-2]
The temperature of the water repellent chemical solution used in Example 5-1, the cleaning solution before the water repellent treatment, and the solvent of the water repellent chemical solution were appropriately changed, and the surface treatment of the wafer with the thermal oxide film was performed and further evaluated. The results are shown in Table 5. In addition, DPGMEA means dipropylene glycol monomethyl ether acetate (boiling point: 213 ° C.), and 13BGDA means 1,3-butylene glycol diacetate (boiling point: 232 ° C.).

[Example 6-1]
(1) Cleaning a wafer with a cleaning solution A wafer with a smooth silicon nitride film (a silicon-based wafer having a silicon nitride layer with a thickness of 50 nm on the surface) is immersed in a 1% by mass hydrofluoric acid aqueous solution at room temperature for 2 minutes, and then at room temperature. 1 minute in pure water, 28% by weight ammonia water: 30% by weight hydrogen peroxide water: water in a 1: 1: 5 (volume ratio) mixture at 70 ° C. for 1 minute, room temperature for 1 minute, iPA, Was immersed in PGMEA (boiling point: 146 ° C.) for 1 minute. Therefore, the cleaning liquid retained on the wafer surface after cleaning is PGMEA.

(2) Preparation of water-repellent chemical solution As silicon compound D, octyldimethyl (dimethylamino) silane [C ₈ H ₁₇ Si (CH ₃ ) ₂ —N (CH ₃ ) ₂ ]; 5 g, trifluoroacetic anhydride as acid D [ {CF ₃ C (O)} ₂ O]; 0.2 g and PGMEA as an organic solvent; 94.8 g are mixed and reacted to form octyldimethylsilyl trifluoroacetate as silicon compound B and octyldimethyl as silicon compound A. A water repellent chemical solution containing (dimethylamino) silane and PGMEA as an organic solvent was obtained. Of the components contained in the water-repellent chemical solution, the component having the largest amount by mass ratio is PGMEA, and its boiling point is 146 ° C.

  Evaluation was performed by treating the surface of the wafer with a silicon nitride film with a water-repellent chemical solution in the same manner as in Example 1-2. The results are shown in Table 6.

[Examples 6-2 to 6-6, Comparative Examples 6-1 to 6-2]
The surface treatment of the wafer with the silicon nitride film was performed by appropriately changing the temperature of the water-repellent chemical solution used in Example 6-1, the cleaning solution before the water-repellent treatment, and the solvent of the water-repellent chemical solution, and further evaluated. The results are shown in Table 6. PGMEA / GBL means a mixed solvent of PGMEA: γ-butyrolactone = 60: 40 (mass ratio). Moreover, among the components contained in the water-repellent chemical solution using the mixed solvent, the component having the largest amount by mass ratio is PGMEA, and the boiling point thereof is 146 ° C.

[Example 7-1]
(1) Cleaning a wafer with a cleaning solution A wafer with a smooth titanium nitride film (a silicon wafer having a titanium nitride layer with a thickness of 50 nm on the surface) is immersed in a 1% by mass hydrogen peroxide solution at room temperature for 1 minute, and then at room temperature. The sample was immersed in pure water for 1 minute and in PGMEA (boiling point: 146 ° C.) for 1 minute. Therefore, the cleaning liquid retained on the wafer surface after cleaning is PGMEA.
(2) Preparation of water repellent chemical perfluorohexylethyl acid _{[C 6 F 13 -C 2 H 4} -P (O) (OH) 2 ]; 0.01 g and, PGMEA as a solvent: iPA = 99.89: A mixed solvent of 0.1 (mass ratio); 99.99 g was mixed and stirred for 18 hours to obtain a water repellent chemical solution. Of the components contained in the water-repellent chemical solution, the component having the largest amount by mass ratio is PGMEA, and its boiling point is 146 ° C.

  Evaluation was performed by treating the surface of the wafer with the titanium nitride film with a water-repellent chemical solution in the same manner as in Example 1-2. The results are shown in Table 7.

[Examples 7-2 to 7-5, Comparative Examples 7-1 to 7-2]
The surface treatment of the wafer with the titanium nitride film was performed by appropriately changing the temperature of the water repellent chemical solution used in Example 7-1, the cleaning solution before the water repellent treatment, and the solvent of the water repellent chemical solution, and further evaluated. The results are shown in Table 7. “DEGEEA / iPA” means a mixed solvent of DEGEA: iPA = 99.89: 0.1 (mass ratio), and among the components contained in the water-repellent chemical liquid using the mixed solvent, the most amount by mass ratio. A component having a high content is DEGEA, and its boiling point is 218 ° C. Further, PGDA / iPA means a mixed solvent of PGDA: iPA = 99.89: 0.1 (mass ratio), and among the components contained in the water-repellent chemical solution using the mixed solvent, the most amount by mass ratio. A component having a large content is PGDA, and its boiling point is 190 ° C. Further, DPGMEA / iPA means a mixed solvent of DPGMEA: iPA = 99.89: 0.1 (mass ratio), and among the components contained in the water-repellent chemical solution using the mixed solvent, the most amount by mass ratio. A component having a large content is DPGMEA, and its boiling point is 213 ° C. Moreover, 13BGDA / iPA means a mixed solvent of 13BGDA: iPA = 99.89: 0.1 (mass ratio), and among the components contained in the water-repellent chemical solution using the mixed solvent, the most amount by mass ratio The component having a large content is 13BGDA, and its boiling point is 232 ° C.

[Example 8-1]
Octylphosphonic acid [C ₈ H ₁₇ -P (O) (OH) ₂ ]; 0.01 g and a mixed solvent of PGMEA: iPA = 99.89: 0.1 (mass ratio) as a solvent; 99.99 g mixed The mixture was the same as Example 7-1 except that the water-repellent chemical solution was obtained by stirring for 18 hours. In addition, among the components contained in the water-repellent chemical solution obtained in this example, the component having the largest amount by mass ratio is PGMEA, and its boiling point is 146 ° C. The results are shown in Table 8.

[Examples 8-2 to 8-4, Comparative Examples 8-1 to 8-2]
The temperature of the water repellent chemical solution used in Example 8-1, the cleaning solution before the water repellent treatment, and the solvent of the water repellent chemical solution were appropriately changed, and the surface treatment of the wafer with the titanium nitride film was performed and further evaluated. The results are shown in Table 8.

[Example 9-1]
Using a wafer with a smooth tungsten film (a silicon wafer having a 50 nm thick tungsten layer on the surface) on the wafer, immerse it in 5% by mass of ammonia water at room temperature for 1 minute, then at room temperature for 1 minute in pure water, PGMEA (Boiling point: 146 ° C.) After being immersed for 1 minute, it was the same as Example 7-1 except that the surface treatment was performed. Therefore, the cleaning liquid retained on the wafer surface after cleaning is PGMEA. The results are shown in Table 9.

[Examples 9-2 to 9-4, Comparative Examples 9-1 to 9-3]
The surface treatment of the wafer with the tungsten film was performed by appropriately changing the temperature of the water-repellent chemical liquid used in Example 9-1, the cleaning liquid before the water-repellent treatment, and the solvent of the water-repellent chemical liquid, and further evaluated. The results are shown in Table 9.

[Example 10-1]
A wafer with a smooth ruthenium film (a silicon wafer having a ruthenium layer with a thickness of 300 nm on the surface) is used for the wafer, soaked in 5% by mass of ammonia water at room temperature for 1 minute, and then at room temperature for 1 minute in pure water, PGMEA (Boiling point: 146 ° C.) After being immersed for 1 minute, it was the same as Example 7-1 except that the surface treatment was performed. Therefore, the cleaning liquid retained on the wafer surface after cleaning is PGMEA. The results are shown in Table 10.

[Examples 10-2 to 10-5, Comparative Examples 10-1 to 10-3]
The surface treatment of the ruthenium film-coated wafer was performed by appropriately changing the temperature of the water-repellent chemical solution used in Example 10-1, the cleaning solution before the water-repellent treatment, and the solvent of the water-repellent chemical solution, and further evaluated. The results are shown in Table 10.

  In the examples, the boiling point of the cleaning liquid before water repellent treatment is 55 to 200 ° C., and the temperature of the water repellent chemical liquid is 40 ° C. or higher and lower than the boiling point of the water repellent chemical liquid. It was confirmed that water repellency can be imparted over time. On the other hand, it was confirmed that the comparative example requires time for imparting water repellency. Therefore, in the comparative example, even when the replacement from the cleaning liquid to the chemical liquid is completed, annealing is performed to increase the chemical liquid temperature and promote the formation of the water-repellent film. Therefore, since additional time is required, water repellency cannot be imparted in a short time as in the embodiment. In addition, it was confirmed that water repellency could be imparted in a shorter time when the temperature of the water-repellent chemical solution was further increased among the examples.

DESCRIPTION OF SYMBOLS 1 Wafer 2 Uneven | corrugated pattern on wafer surface 3 Pattern convex part 4 Pattern concave part 5 Concave width 6 Convex height 7 Convex width 8 Cleaning liquid 9 Water-repellent chemical liquid 10 Mixing of cleaning liquid and water-repellent chemical liquid 11 Cleaning liquid Of water evaporation 12 Water repellent coating

Claims (10)

A method for cleaning a wafer having a concavo-convex pattern on a surface, at least,
Cleaning the wafer with a cleaning liquid;
A step of replacing the cleaning liquid held in the recesses of the wafer with a water repellent chemical after the cleaning,
A step of drying the wafer;
The cleaning liquid contains 80% by mass or more of a solvent having a boiling point of 55 to 200 ° C.,
A method for cleaning a wafer, wherein at least the surface of the concave portion is made water-repellent by setting the temperature of the water-repellent chemical solution provided in the replacing step to 40 ° C. or higher and lower than the boiling point of the water-repellent chemical solution. . The cleaning liquid is at least one liquid selected from the group consisting of an organic solvent, water, and an aqueous solution in which at least one of an organic solvent, an acid, an alkali, and an oxidizing agent is mixed in water. 2. The method for cleaning a wafer according to 1. The wafer is a wafer containing a silicon element on the surface of the recess, and the water repellent chemical solution contains a silicon compound A represented by the following general formula [1], or a silicon compound A and an acid or base. The wafer cleaning method according to claim 1, wherein the wafer cleaning method includes the wafer cleaning method.
(R ¹ ) _a Si (H) _b X ¹ _4-ab [1]
[In the formula [1], each R ¹ independently contains a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. Valent organic group. X ¹ is independently of each other a monovalent functional group in which the element bonded to the silicon element is nitrogen, a monovalent functional group in which the element bonded to the silicon element is oxygen, a halogen group, a nitrile group, And at least one group selected from the group consisting of —CO—NH—Si (CH ₃ ) ₃ . 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. ] The water-repellent chemical solution contains an acid, and the acid is represented by hydrogen chloride, sulfuric acid, perchloric acid, phosphoric acid, a sulfonic acid represented by the following general formula [2] and its anhydride, and a general formula [3] below. Carboxylic acids and anhydrides thereof, alkylborates, arylborates, tris (trifluoroacetoxy) borane, trialkoxyboroxine, trifluoroboron, a group consisting of silicon compound B represented by the following general formula [4] The wafer cleaning method according to claim 3, wherein at least one selected from the group consisting of:
R ² S (O) ₂ OH [2]
[In the formula [2], R ² is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. ]
R ³ COOH [3]
[In the formula [3], R ³ is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. ]
(R ⁴ ) _c Si (H) _d X ² _4-cd [4]
[In the formula [4], each R ⁴ independently represents a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. X ² is independently of each other a chloro group, —OCO—R ⁵ (R ⁵ is a C 1 -C 1, wherein some or all of the hydrogen elements may be replaced by fluorine elements. Valent hydrocarbon group) and —OS (O) ₂ —R ⁶ (R ⁶ is a monovalent hydrocarbon having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements) Represents at least one group selected from the group consisting of (hydrocarbon groups). 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 acid is trimethylsilyl trifluoroacetate, trimethylsilyl trifluoromethanesulfonate, dimethylsilyl trifluoroacetate, dimethylsilyl trifluoromethanesulfonate, butyldimethylsilyl trifluoroacetate, butyldimethylsilyl trifluoromethanesulfonate, hexyldimethylsilyl trifluoroacetate, hexyldimethylsilyl. Trifluoromethanesulfonate, octyldimethylsilyl trifluoroacetate, octyldimethylsilyl trifluoromethanesulfonate, decyldimethylsilyl trifluoroacetate, decyldimethylsilyl trifluoromethanesulfonate, dodecyldimethylsilyl trifluoroacetate, dodecyldimethylsilyl trifluoromethanesulfone Is at least one of, characterized in that, the method of cleaning a wafer according to claim 3 or claim 4 selected from the group consisting of chromatography and. The silicon compound A is hexamethyldisilazane, trimethylsilyldimethylamine, trimethylsilyldiethylamine, tetramethyldisilazane, dimethylsilyldimethylamine, dimethylsilyldiethylamine, 1,3-dibutyltetramethyldisilazane, butyldimethylsilyldimethylamine, butyldimethyl. Silyldiethylamine, 1,3-dihexyltetramethyldisilazane, hexyldimethylsilyldimethylamine, hexyldimethylsilyldiethylamine, 1,3-dioctyltetramethyldisilazane, octyldimethylsilyldimethylamine, octyldimethylsilyldiethylamine, 1,3-di Decyltetramethyldisilazane, decyldimethylsilyldimethylamine, decyldimethylsilyldiethylamine, 1,3-dide 6. The wafer cleaning method according to claim 3, wherein the wafer cleaning method is at least one selected from the group consisting of siltetramethyldisilazane, dodecyldimethylsilyldimethylamine, and dodecyldimethylsilyldiethylamine. . The water-repellent chemical solution contains a base, which is ammonia, N, N, N ′, N′-tetramethylethylenediamine, triethylenediamine, dimethylaniline, alkylamine, dialkylamine, trialkylamine, pyridine, piperazine, N 7. The wafer cleaning method according to claim 3, wherein the wafer is at least one selected from the group consisting of an alkylmorpholine and a silicon compound C represented by the following general formula [5]. .
(R ⁷ ) _e Si (H) _f X ³ _4-ef [5]
[In the formula [5], R ⁷ are each independently a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. In addition, X ³ is a monovalent functional group that is independent of each other, and the element bonded to the silicon element is nitrogen, and may contain a fluorine element or a silicon 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 1 to 3. ] The wafer is a wafer containing at least one element of titanium, tungsten, aluminum, copper, tin, tantalum, and ruthenium on the surface of the recess, and the water-repellent chemical liquid has the following general formula [6] The method for cleaning a wafer according to claim 1 or 2, comprising at least one selected from the group consisting of a compound represented by-[12] and a salt compound thereof and a solvent.
_{^{R 8 -P (= O) -}} (OH) g (R 9) 2-g [6]
[In Formula [6], R ⁸ is a monovalent hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced by fluorine elements. R ⁹ is each independently a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms in which some or all of the hydrogen elements may be replaced with fluorine elements. g is an integer of 0 to 2. ]
R ¹⁰ —C (═O) —X ⁴ [7]
[In the formula [7], R ¹⁰ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. . X ⁴ represents a group selected from the group consisting of a fluoro group, a chloro group, a bromo group, and an iodo group. ]
R ¹¹ R ¹² R ¹³ N [8]
[In the formula [8], R ¹¹ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. R ¹² is a hydrogen element, a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms, or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. R ¹³ is a hydrogen element, a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms, or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. ]
R ¹⁴ —C (═O) —X ⁵ —X ⁶ [9]
[In the formula [9], R ¹⁴ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. . X ⁵ represents an oxygen element or a sulfur element, and X ⁶ represents a hydrogen element, an alkyl group, an aromatic group, a pyridyl group, a quinolyl group, a succinimide group, a maleimide group, a benzoxazole group, a benzothiazole group, and a benzoic acid group. The group chosen from the group which consists of a triazole group is shown, The hydrogen element in these groups may be substituted by the organic group. ]
R ¹⁵ (X ⁷ ) _h [10]
[In Formula [10], X ⁷ is each independently at least one group selected from the group consisting of an isocyanate group, a mercapto group, an aldehyde group, a —CONHOH group, and a ring structure containing a nitrogen element. , H is an integer of 1 to 6, R ¹⁵ is an organic group containing a hydrocarbon group having 1 to 18 carbon atoms, or an organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms, In which the same number of hydrogen elements are substituted with at least one group selected from the group consisting of an isocyanate group, a mercapto group, an aldehyde group, a —CONHOH group, and a ring structure containing a nitrogen element. ]
R ¹⁶ -X ⁸ [11]
[In the formula [11], X ⁸ is a ring structure containing a sulfur element, R ¹⁶ is a hydrogen element, a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms, or 1 carbon atom. A monovalent organic group containing from 8 to 8 fluoroalkyl chains. ]
R ¹⁷ —C (═O) —X ⁹ —C (═O) —R ¹⁸ [12]
[In the formula [12], R ¹⁷ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. . R ¹⁸ is a monovalent organic group containing a hydrocarbon group having 1 to 18 carbon atoms or a monovalent organic group containing a fluoroalkyl chain having 1 to 8 carbon atoms. X ⁹ represents an oxygen element or a sulfur element. ] The temperature of the water-repellent chemical solution provided in the replacing step is set to 70 ° C. or higher and lower than (boiling point of the water-repellent chemical solution −10 ° C.). The method for cleaning a wafer as described. A water repellent chemical used in the wafer cleaning method according to claim 1.

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