Substrate processing method and substrate processing apparatus

Abstract

To provide a substrate processing method and a substrate processing apparatus, capable of efficiently forming a self-assembled monomolecular layer excellent in denseness and protection performance on a substrate surface in a short time by suppressing or reducing the occurrence of film defects.SOLUTION: The present invention relates to a substrate processing method for forming a SAM on a surface of a substrate. The substrate processing method includes: a dispersion liquid generation step S101 of generating a dispersion liquid which contains water, a neutralizing agent, and an organic solvent as a main solvent and in which water is dispersed; a processing liquid generation step S102 of generating a processing liquid by adding, to the dispersion liquid, a material having a functional group exhibiting hydrolysis reactivity and containing molecules capable of forming the SAM; and a film formation step S103 of forming the SAM by supplying the processing liquid to the surface of the substrate. The dispersion liquid generation step S101 is a step of generating a molecule in a state having a hydroxyl group by subjecting the water dispersed in the dispersion liquid and the functional group to a hydrolysis reaction, and neutralizing an acid or a base generated by the hydrolysis reaction with a neutralizing agent.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a substrate processing method and a substrate processing apparatus capable of efficiently forming a self-assembled monolayer excellent in airtightness and protective performance on a substrate in a short time.

Background Art

[0002] In the manufacture of semiconductor devices, photolithography technology is widely used as a technology for selectively forming a film on a specific surface region of a substrate. For example, after forming an insulating film after forming a lower layer wiring, a dual damascene structure having trenches and via holes is formed by photolithography and etching, and a conductive film such as Cu is embedded in the trenches and via holes to form a wiring.

[0003] However, recently, the miniaturization of semiconductor devices has been increasingly progressing, and there are cases where the alignment accuracy is not sufficient in photolithography technology. For this reason, a method for selectively forming a film with high precision on a specific region of the substrate surface is required instead of photolithography technology.

[0004] For example, in Patent Document 1, in a substrate provided with a silicon nitride (SiN) film and a silicon oxide (SiO2) film in a plane, in order to selectively etch the silicon nitride film, a heat-resistant phosphoric acid material is formed in advance on the surface of the silicon oxide film as a self-assembled monolayer (hereinafter, sometimes referred to as "SAM").

[0005] Here, in order to sufficiently protect the silicon oxide film from an etching solution, it is necessary to form a SAM excellent in airtightness. However, in the conventional method for forming a SAM, it is difficult to form such a SAM excellent in airtightness in a short time, and there is a problem of inferior production efficiency.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The present invention has been made in view of the above problems, and an object thereof is to efficiently form a self-assembled monolayer excellent in airtightness and protective performance on the surface of a substrate in a short time by suppressing or reducing the occurrence of film defects. It is to provide a substrate processing method and a substrate processing apparatus capable of doing so.

Means for Solving the Problems

[0008] The substrate processing method according to the present invention is a substrate processing method for forming a self-assembled monolayer on the surface of a substrate. In order to solve the above problems, the method includes a dispersion liquid generation step of generating a dispersion liquid containing water, a neutralizing agent, and an organic solvent as a main solvent, and in which the water is dispersed; a treatment liquid generation step of adding a material containing a functional group exhibiting hydrolysis reactivity and a molecule capable of forming the self-assembled monolayer to the dispersion liquid to generate a treatment liquid; and a film formation step of forming the self-assembled monolayer by supplying the treatment liquid to the surface of the substrate. The treatment liquid generation step is characterized in that the water dispersed in the dispersion liquid and the functional group are caused to undergo a hydrolysis reaction to generate the molecule in a state having a hydroxyl group, and the acid or base generated by the hydrolysis reaction is neutralized by the neutralizing agent.

[0009] According to the above configuration, in the dispersion liquid generation step, a dispersion liquid containing water, a neutralizing agent, and an organic solvent and in which water is dispersed is generated. Further, in the treatment liquid generation step, a material containing molecules capable of forming a self-assembled monolayer (hereinafter sometimes referred to as "SAM") (hereinafter sometimes referred to as "SAM molecules") is added to the dispersion liquid generated in the dispersion liquid generation step to generate a treatment liquid. Here, the SAM molecules have a functional group exhibiting hydrolysis reactivity, and water molecules are dispersed and present in the dispersion liquid. Therefore, when the SAM-forming material is added to the dispersion liquid, the functional group exhibiting hydrolysis reactivity in the SAM molecules undergoes a hydrolysis reaction with the water molecules in the dispersion liquid to become a hydroxyl group (OH group). Thus, in the above configuration, it is possible to introduce a hydroxyl group in advance at the treatment liquid generation stage for the SAM molecules to be chemisorbed on the substrate surface, and compared with the conventional substrate treatment method of forming a SAM using SAM molecules without a hydroxyl group introduced, the hydrolysis reaction of the SAM molecules, which is the rate-determining step in the SAM film formation process, can be omitted.

[0010] On the other hand, in the above-mentioned hydrolysis reaction, an acid or a base is also by-produced. Since these by-products increase over time as the hydrolysis reaction progresses, the hydrolysis reaction of the SAM molecules is gradually inhibited. However, since the treatment liquid having the above configuration also contains a neutralizing agent for neutralizing the acid or the base, the by-products that inhibit the progress of the hydrolysis reaction can be removed by neutralization. As a result, since the treatment liquid having the above configuration can contain more SAM molecules having a hydroxyl group, a dense SAM can be formed as compared with the conventional substrate treatment method. Further, in order to form a dense SAM, it is not necessary to keep the SAM molecules in contact with the substrate surface for a long time, and a SAM excellent in film defect suppression, density, and protective performance can be efficiently formed in a short time.

[0011] In the above configuration, as the neutralizing agent, it is preferable to use one that satisfies the following relational expressions (1) and (2) for the Hansen solubility parameters δp (MPa 1 / 2 ) and δh (MPa 1 / 2 ). δp1 < δp < δp2 (1) (wherein, δp1 (MPa 1 / 2 ) represents the polar term in the Hansen solubility parameter of the organic solvent, and δp2 (MPa 1 / 2 ) represents the polar term in the Hansen solubility parameter of a molecule having a functional group exhibiting the hydrolysis reactivity and capable of forming the self-assembled monolayer.) δh1 < δh < δh2 (2) (wherein, δh1 (MPa 1 / 2 ) represents the hydrogen bonding term in the Hansen solubility parameter of the organic solvent, and δh2 (MPa 1 / 2 ) represents the hydrogen bonding term in the Hansen solubility parameter of a molecule having a functional group exhibiting the hydrolysis reactivity and capable of forming the self-assembled monolayer.)

[0012] According to the above configuration, by using, as the neutralizing agent, one having smaller values of δp and δh of the Hansen solubility parameter than the SAM molecule, when the SAM molecule introduced with a hydroxyl group chemisorbs on the substrate surface, it is possible to prevent or reduce being inhibited by the neutralizing agent. Further, by using, as the neutralizing agent, one having larger values of δp and δh than the organic solvent, when the SAM molecule introduced with a hydroxyl group chemisorbs on the substrate surface, the neutralizing agent prevents or reduces being inhibited by the organic solvent. That is, according to the above configuration, the SAM molecule introduced with a hydroxyl group can be chemisorbed on the substrate surface without being inhibited by the neutralizing agent or the organic solvent, thereby enabling the formation of a SAM having further excellent denseness and protective performance.

[0013] In the above configuration, in the treatment liquid generation step, when the acid is generated by the hydrolysis reaction, it is preferable to use, as the neutralizing agent, an amine compound satisfying the relational expressions (1) and (2).

[0014] Furthermore, in the above configuration, it is preferable that the amine compound is at least one selected from the group consisting of trimethylamine, triethylamine, and diisopropylamine.

[0015] Also, in the above configuration, it is preferable that the dispersion liquid generation step is a step of dispersing the water in the organic solvent by mixing at least the water with the organic solvent while applying ultrasonic waves, or by applying ultrasonic waves after mixing at least the water with the organic solvent.

[0016] Thereby, a dispersion liquid in which water is uniformly dispersed in the dispersion liquid can be obtained. Also, when adding the SAM forming material to the dispersion liquid, it is possible to prevent or reduce the aggregation of SAM molecules into which hydroxyl groups have been introduced by the hydrolysis reaction, and a treatment liquid is generated. As a result, more SAM molecules can be chemisorbed on the substrate surface, and a SAM having more excellent denseness and protective performance can be formed in a short time.

[0017] The substrate processing apparatus of the present invention is a substrate processing apparatus for forming a self-assembled monolayer on the surface of a substrate in order to solve the above problems, and includes a treatment liquid generation unit for generating a treatment liquid containing a molecule capable of forming the self-assembled monolayer, and a treatment liquid supply unit for forming the self-assembled monolayer by supplying the treatment liquid generated by the treatment liquid generation unit to the surface of the substrate. The treatment liquid generation unit includes water, a neutralizing agent, and an organic solvent as a main solvent, and after generating a dispersion liquid in which the water is dispersed in the organic solvent, a material containing a molecule having a functional group exhibiting hydrolytic reactivity and capable of forming the self-assembled monolayer is added to the dispersion liquid to cause a hydrolysis reaction between the water and the functional group contained in the dispersion liquid to generate the molecule in a state having a hydroxyl group, and the acid or base generated by the hydrolysis reaction is neutralized with the neutralizing agent to generate the treatment liquid.

[0018] According to the above configuration, the treatment liquid generation unit generates a dispersion liquid containing water, a neutralizing agent, and an organic solvent, and in which water is dispersed. Further, the treatment liquid generation unit generates a treatment liquid by adding a SAM forming material to the obtained dispersion liquid. Here, the SAM molecule has a functional group exhibiting hydrolysis reactivity, and water molecules are dispersed in the dispersion liquid. Therefore, when the SAM forming material is added to the dispersion liquid, the functional group of the SAM molecule exhibiting hydrolysis reactivity undergoes a hydrolysis reaction with the water molecules in the dispersion liquid to become a hydroxyl group (OH group). Thus, in the above configuration, it is possible to cause a hydrolysis reaction in advance at the treatment liquid generation stage to introduce a hydroxyl group into the SAM molecule to be chemisorbed on the substrate surface, and compared with a conventional substrate treatment apparatus that forms a SAM using a SAM molecule without a hydroxyl group introduced, the hydrolysis reaction of the SAM molecule, which is the rate-determining step in the SAM film formation process, can be omitted.

[0019] On the other hand, in the above hydrolysis reaction, an acid or a base is also by-produced. Since these by-products increase over time as the hydrolysis reaction progresses, the hydrolysis reaction of the SAM molecule is gradually inhibited. However, since the treatment liquid generation unit of the above configuration generates a treatment liquid containing a neutralizing agent that neutralizes the acid or the base, the by-products that inhibit the progress of the hydrolysis reaction can be removed by neutralization. As a result, in the above configuration, it is possible to generate a treatment liquid containing more SAM molecules having a hydroxyl group, and compared with a conventional substrate treatment apparatus, a dense SAM can be formed. Further, even without bringing the SAM molecules into contact with the substrate surface for a long time for the formation of a dense SAM, the occurrence of film defects can be suppressed, and a SAM excellent in density and protective performance can be efficiently formed in a short time.

[0020] In the above configuration, as the neutralizing agent, it is preferable to use one that satisfies the following relational expressions (1) and (2) for the Hansen solubility parameters δp (MPa 1 / 2 ) and δh (MPa 1 / 2 ). δp1 < δp < δp2 (1) (In the formula, δp1 (MPa 1 / 2) represents the polar term in the Hansen solubility parameter of a molecule having a functional group exhibiting the hydrolysis reactivity and capable of forming the self-assembled monolayer, δp2 (MPa 1 / 2 ) represents the polar term in the Hansen solubility parameter of the organic solvent.) δh1 < δh < δh2 (2) (In the formula, δh1 (MPa 1 / 2 ) represents the hydrogen bonding term in the Hansen solubility parameter of a molecule having a functional group exhibiting the hydrolysis reactivity and capable of forming the self-assembled monolayer, δh2 (MPa 1 / 2 ) represents the hydrogen bonding term in the Hansen solubility parameter of the organic solvent.)

[0021] According to the above configuration, by using, as the neutralizing agent, one having smaller values of δp and δh in the Hansen solubility parameter than the SAM molecule, when the SAM molecule introduced with a hydroxyl group chemisorbs on the substrate surface, it is possible to prevent or reduce the inhibition by the neutralizing agent. Also, by using, as the neutralizing agent, one having larger values of δp and δh than the organic solvent, when the SAM molecule introduced with a hydroxyl group chemisorbs on the substrate surface, the neutralizing agent prevents or reduces the inhibition by the organic solvent. That is, according to the above configuration, the SAM molecule introduced with a hydroxyl group can be chemisorbed on the substrate surface without being inhibited by the neutralizing agent or the organic solvent, enabling the formation of a SAM with even better tightness and protective performance.

[0022] In the above configuration, when the acid is generated by the hydrolysis reaction in the treatment liquid generation unit, it is preferable to use, as the neutralizing agent, an amine compound that satisfies the relational expressions (1) and (2).

[0023] Furthermore, in the above configuration, it is preferable that the amine compound is at least one selected from the group consisting of trimethylamine, triethylamine, and diisopropylamine.

[0024] In the above configuration, in the treatment liquid generation unit, while applying ultrasonic waves, at least the water is mixed with the organic solvent, or after at least the water is mixed with the organic solvent, ultrasonic waves are applied to disperse the water in the organic solvent, and it is preferable to further include an ultrasonic application unit.

[0025] When at least water is mixed with the organic solvent in the treatment liquid generation unit, or after at least water is mixed with the organic solvent, the ultrasonic application unit applies ultrasonic waves, whereby a dispersion liquid in which water is uniformly dispersed in the organic solvent can be generated. And when adding the SAM forming material to the dispersion liquid, since the treatment liquid is generated by preventing or reducing the aggregation of SAM molecules into which hydroxyl groups have been introduced by the hydrolysis reaction, more SAM molecules can be chemisorbed on the substrate surface. As a result, a SAM having better density, protection performance and being formed in a shorter time can be formed.

Advantages of the Invention

[0026] According to the present invention, it is possible to provide a substrate processing method and a substrate processing apparatus capable of efficiently forming a self-assembled monolayer having a high film density, excellent denseness, good suppression or reduction of film defects, and excellent protection performance on the substrate surface in a shorter time than before.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0028] (Substrate Processing Method) First, the substrate processing method according to the present embodiment will be described below with reference to the drawings. The substrate processing method of the present embodiment provides a technique for forming a SAM on the surface of a substrate, which has excellent tightness and can exhibit good protective performance. The substrate processing method of the present embodiment can be applied, for example, to a part of the process of a manufacturing method of a semiconductor device that forms a three-dimensional structure such as a three-dimensional NAND structure on the surface of a substrate.

[0029] In this specification, the “substrate” refers to various substrates such as at least a semiconductor substrate whose surface is made of a metal oxide, a glass substrate for a photomask, a glass substrate for a liquid crystal display, a glass substrate for a plasma display, a substrate for a FED (Field Emission Display), a substrate for an optical disk, a substrate for a magnetic disk, and a substrate for a magneto-optical disk. The metal oxide is not particularly limited, and examples thereof include SiO2 and the like.

[0030] As shown in FIG. 1, the substrate processing method of the present embodiment includes at least a dispersion liquid generation step S101, a processing liquid generation step S102, a SAM formation step (film formation step) S103, a removal step S104, and a drying step S105. FIG. 1 is a flowchart showing an example of the overall flow of the substrate processing method according to the present embodiment.

[0031] <Dispersion Generation Step> The dispersion generation step S101 is a step of generating a dispersion containing water, a neutralizing agent, and an organic solvent as the main solvent. Water exists in a state of being uniformly dispersed in the dispersion. Here, the fact that water is uniformly dispersed in the dispersion means, for example, that water exists in the dispersion in the form of an emulsion. Also, the "main solvent" means the solvent with the largest volume ratio when using a mixed solvent composed of a plurality of solvents.

[0032] Examples of the organic solvent as the main solvent include ether solvents, aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, fluorine solvents, ketone solvents, etc. The ether solvent is not particularly limited, and examples include tetrahydrofuran (THF), etc. The aromatic hydrocarbon solvent is not particularly limited, and examples include toluene, etc. The aliphatic hydrocarbon solvent is not particularly limited, and examples include hexane, decane, etc. The fluorine solvent is not particularly limited, and examples include 1,3-bis(trifluoromethyl)benzene, etc. The ketone solvent is not particularly limited, and examples include methyl ethyl ketone, etc. These solvents can be used alone or in combination of two or more. Among the exemplified solvents, from the viewpoint of affinity with water, aromatic hydrocarbon solvents are preferred, and toluene is particularly preferred.

[0033] Also, as the organic solvent as the main solvent, those with low solubility of water are preferred. Thereby, water can be well dispersed in the dispersion. Examples of the organic solvent with low solubility of water include the aforementioned toluene, etc.

[0034] Examples of the neutralizing agent include compounds capable of neutralizing the acid or base generated when the SAM forming material is added to the dispersion in the treatment liquid generation step S102 (details of the neutralizing agent will be described later).

[0035] As methods for producing the dispersion liquid, there may be mentioned a method of mixing at least water into an organic solvent while applying ultrasonic waves, and a method of applying ultrasonic waves after mixing at least water into the organic solvent. By applying ultrasonic waves, it is possible to prevent the formation of a liquid mixture that has phase-separated into an organic solvent phase and an aqueous phase. That is, by applying ultrasonic waves, cavitation is generated in the organic solvent, and by disturbing the interface between the organic solvent and water, the water is granulated. As a result, compared with stirring and mixing by applying mechanical forces such as stirring and shaking, fine particle water can be uniformly dispersed in the organic solvent, and a dispersion liquid excellent in dispersion stability can be produced. In the present invention, when applying ultrasonic waves, it is possible to omit the addition of an emulsifier.

[0036] Here, the order of adding the neutralizing agent to the organic solvent is not particularly limited. For example, when the method for producing the dispersion liquid is the former, the neutralizing agent may be added to the organic solvent in advance, may be added to the organic solvent simultaneously with water, or may be added to the organic solvent after the addition of water. When the neutralizing agent is added after the addition of water, the application of ultrasonic waves may be continued as it is. Also, even when the method for producing the dispersion liquid is the latter, the neutralizing agent may be added to the organic solvent in advance, may be added to the organic solvent simultaneously with water, or may be added to the organic solvent after the addition of water. When adding the neutralizing agent to the organic solvent after the addition of water, the addition may be before the application of ultrasonic waves, during the application of ultrasonic waves, or after the application of ultrasonic waves.

[0037] The amount of water added to the dispersion is preferably in the range of 50 ppm or more and 200 ppm or less, and more preferably in the range of 50 ppm or more and 150 ppm or less. By setting the amount of water added to 50 ppm or more, it is possible to prevent the hydrolysis reaction of the functional group exhibiting hydrolysis reactivity in the SAM molecules added in the subsequent treatment liquid generation step S102 from becoming insufficient. That is, in the stage of generating the treatment liquid, a sufficient amount of SAM molecules having a hydroxyl group introduced therein can be present in the treatment liquid. As a result, it is possible to suppress the occurrence of film defects and form a SAM with excellent denseness without bringing the SAM molecules into contact with the substrate surface for a long time as in the conventional substrate treatment method. On the other hand, by setting the amount of water added to 200 ppm or less, it is possible to suppress the excessive aggregation of SAM molecules having a hydroxyl group by a dehydration condensation reaction. As a result, it is possible to suppress a decrease in the density of the SAM molecules chemisorbed on the substrate surface and form a SAM with excellent denseness.

[0038] The amount of the neutralizing agent added to the dispersion is not particularly limited, but in the treatment liquid generation step S102, it is preferably an amount capable of neutralizing the acid or base by-produced by adding the SAM forming material to the dispersion, and more specifically, it is preferably equal to or more than the equimolar amount of water in the dispersion.

[0039] Further, the dispersion liquid generation step S101 is preferably performed, for example, in an atmosphere of an inert gas such as nitrogen gas. If this step is performed in an environment where moisture is present in the atmosphere, moisture in the atmosphere dissolves in the dispersion liquid, and as a result, a dispersion liquid with a predetermined amount of moisture cannot be obtained, which is not preferable.

[0040] The conditions for applying ultrasonic waves in the dispersion liquid generation step S101, specifically, for example, the application time, frequency, sound wave intensity, etc. are not particularly limited as long as water is dispersed in the organic solvent, and can be set as appropriate according to need. Also, the method for applying ultrasonic waves is not particularly limited, and examples include a method in which an ultrasonic vibrator is immersed in an organic solvent containing at least water and the ultrasonic vibrator is vibrated to apply ultrasonic waves.

[0041] <Treatment liquid generation step> The treatment liquid generation step S102 is a step of generating a treatment liquid containing SAM molecules. Specifically, the generation of the treatment liquid is performed by adding a SAM forming material to the dispersion prepared in the dispersion generation step S101. In this step, when adding the SAM forming material to the dispersion and after adding the SAM forming material to the dispersion, it is preferably performed without applying ultrasonic waves. By not applying ultrasonic waves, a treatment liquid can be generated such that SAM molecules exist without aggregating with each other. Thereby, SAM can be favorably formed in the SAM formation step S103.

[0042] The SAM forming material is not particularly limited as long as it contains SAM molecules having a functional group exhibiting hydrolytic reactivity. Also, as the SAM forming material, those having high affinity (solubility) for the aforementioned organic solvent are preferable. Specifically, the SAM forming material is, for example, octadecyltrichlorosilane (C 18 H 37 SiCl3), decyltrichlorosilane (C 10 H 21 SiCl3), trichloropropylsilane (C3H7SiCl3), and trichloromethylsilane (CH3SiCl3) and other organosilane compounds; 1,1,1,3,3,3 - hexamethyldisilazane (C6H 19 NSi2) and other organic amine compounds. The exemplified organosilane compounds have a trichlorosilyl group as a functional group exhibiting hydrolytic reactivity, and the organic amine compounds have a trimethylsilyl group as a functional group exhibiting hydrolytic reactivity.

[0043] SAM molecules before being added to the treatment liquid have a functional group exhibiting hydrolytic reactivity. Therefore, when the SAM forming material is added to the dispersion, the functional group undergoes a hydrolysis reaction with water molecules uniformly dispersed in the dispersion. As a result, the functional group exhibiting hydrolytic reactivity in the SAM molecules becomes a hydroxyl group (OH group). Note that water molecules are uniformly dispersed in the dispersion. Therefore, it is possible to suppress or reduce the dehydration condensation reaction and aggregation between SAM molecules into which hydroxyl groups have been introduced.

[0044] Here, the treatment liquid of the present embodiment contains the above-described neutralizing agent. This neutralizing agent can cause a neutralization reaction with an acid or a base generated by the hydrolysis reaction of the SAM molecule. Therefore, in the hydrolysis reaction, when the reverse reaction has a smaller activation energy than the forward reaction and the hydrolysis reaction is difficult to proceed, as a result of the neutralizing agent neutralizing the acid or base by-products, the hydrolysis reaction can be promoted. Thereby, a treatment liquid containing a SAM molecule having a hydroxyl group can be generated, and the formation of SAM on the substrate surface can be facilitated as compared with the case of forming SAM using a SAM molecule into which a hydroxyl group has not been introduced.

[0045] For example, when the SAM molecule is octadecyltrichlorosilane, the hydrolysis reactions represented by the following reaction formulas (1) to (3) proceed sequentially, and finally, a SAM molecule in which all chlorosilyl groups are substituted with hydroxyl groups is obtained. Also, in each hydrolysis reaction, hydrochloric acid is generated as a by-product.

[0046]

Chemical formula

[0047] Here, in reaction formulas (1) to (3), Table 1 shows the activation energies of the forward reaction and the reverse reaction, respectively.

[0048]

Table 1

[0049] As can be seen from Table 1, when the SAM molecule is octadecyltrichlorosilane, in the hydrolysis reaction represented by Reaction Formula (1), since the value of (E1 - E2) (kJ / mol) is negative and the difference is large, the forward reaction proceeds more easily than the reverse reaction. On the other hand, in the hydrolysis reactions represented by Reaction Formulas (2) and (3), since the value of (E1 - E2) (kJ / mol) is positive, the reverse reaction proceeds more easily than the forward reaction. That is, in the hydrolysis reactions represented by Reaction Formulas (2) and (3), the forward reaction is less likely to occur in terms of activation energy than the hydrolysis reaction represented by Reaction Formula (1).

[0050] However, since the treatment liquid of the present embodiment contains a neutralizing agent, by causing a neutralization reaction between this neutralizing agent and the acid or base by-produced by the above-described hydrolysis reaction, these by-products can be removed. As a result, in the present embodiment, also in the hydrolysis reactions represented by Reaction Formulas (2) and (3), it is possible to promote the forward reaction to occur preferentially with respect to the reverse reaction.

[0051] Here, the neutralizing agent is not particularly limited as long as it causes a neutralization reaction with the acid or base by-produced by the hydrolysis reaction of the SAM molecule as described above. Further, it is preferable that the neutralizing agent does not inhibit the chemisorption of the SAM molecule having a hydroxyl group on the substrate surface after the hydrolysis reaction. Also, as the neutralizing agent, it is preferable that it can suppress the inhibition of the chemisorption by an organic solvent when the SAM molecule having a hydroxyl group chemisorbs on the substrate surface. Here, when the degree of adsorption of the SAM molecule having a hydroxyl group, the neutralizing agent, and the organic solvent on the substrate surface is considered from the viewpoint of solvation, such a preferable neutralizing agent has a polar term δp (MPa 1 / 2 ) and a hydrogen bond term δh (MPa 1 / 2 ) in the Hansen solubility parameter (HSP). That is, as the neutralizing agent, those in which δp and δh in the Hansen solubility parameter satisfy the following relational expressions (1) and (2) are preferable.

[0052] δp1 < δp < δp2 (1) (wherein, δp1 (MPa 1 / 2 ) represents the polar term in the Hansen solubility parameter of the organic solvent, and δp2 (MPa 1 / 2 ) represents the polar term in the Hansen solubility parameter of the SAM molecule having a functional group exhibiting hydrolytic reactivity.) δh1 < δh < δh2 (2) (wherein, δh1 (MPa 1 / 2 ) represents the hydrogen bonding term in the Hansen solubility parameter of the organic solvent, and δh2 (MPa 1 / 2 ) represents the hydrogen bonding term in the Hansen solubility parameter of the SAM molecule having a functional group exhibiting hydrolytic reactivity.)

[0053] As shown in the relational expressions (1) and (2), as the neutralizing agent, by selecting one whose δp and δh are smaller than δp2 and δh2 of the SAM molecule having a functional group exhibiting hydrolytic reactivity, it is possible to suppress the chemisorption of the neutralizing agent on the substrate surface more than the SAM molecule having a hydroxyl group. Further, as the neutralizing agent, by selecting one whose δp and δh are larger than δp1 and δh1 of the organic solvent, the neutralizing agent inhibits the chemisorption of the organic solvent on the substrate surface. As a result, it is possible to promote the chemisorption of the SAM molecule having a hydroxyl group on the substrate surface more effectively. Thereby, when using a neutralizing agent that satisfies the relational expressions (1) and (2), the SAM molecule having a hydroxyl group can chemisorb on the substrate surface without being inhibited by the neutralizing agent or the organic solvent, and a SAM with even better denseness can be formed.

[0054] More specifically, the neutralizing agent includes an amine compound that satisfies the relational expressions (1) and (2) when an acid is generated by a hydrolysis reaction. Further, examples of the amine compound include trimethylamine (δp = 3.4 MPa 1 / 2 , δh = 1.8 MPa 1 / 2 ), triethylamine (δp = 0.4 MPa 1 / 2 , δh = 1.0 MPa 1 / 2 ) and diisopropylamine (δp = 1.7 MPa 1 / 2 , δh = 3.5 MPa 1 / 2At least one selected from the group consisting of

[0055] When the SAM molecule is the aforementioned octadecyltrichlorosilane (δp2 = 4.7 MPa 1 / 2 , δh2 = 4.0 MPa 1 / 2 ), when toluene (δp1 = 1.4 MPa 1 / 2 , δh1 = 2.0 MPa 1 / 2 ) is used as the organic solvent, as the neutralizing agent, for example, diisopropylamine satisfying the relational expressions (1) and (2) is preferable. Further, when hexane (δp1 = 0 MPa 1 / 2 , δh1 = 0 MPa 1 / 2 ) is used as the organic solvent, as the neutralizing agent, for example, trimethylamine, triethylamine, and diisopropylamine satisfying the relational expressions (1) and (2) are preferable.

[0056] The addition amount of the SAM forming material is preferably in the range of 0.05% by mass or more and 5% by mass or less with respect to the total mass of the treatment liquid.

[0057] Further, the treatment liquid may contain known additives within a range that does not inhibit the effects of the present invention. The additives are not particularly limited, and examples thereof include stabilizers and surfactants.

[0058] The treatment liquid generation step S102 is preferably performed in a static state. More specifically, when adding the SAM forming material to the dispersion liquid, it is not preferable to apply mechanical forces such as stirring and shaking to the dispersion liquid. When adding the SAM forming material to the dispersion liquid while applying mechanical forces such as stirring and shaking to the dispersion liquid, the SAM molecules may aggregate with each other. However, by adding the SAM forming material to the dispersion liquid in a static state and adjusting the treatment liquid, the aggregation of the SAM molecules can be further suppressed to generate the treatment liquid.

[0059] Further, the treatment liquid generation step S102 can be performed, for example, at normal temperature and normal pressure. In this specification, "normal temperature" means a temperature range of 5°C to 35°C. Also, in this specification, "normal pressure" means the pressure near the standard state of the atmosphere (standard atmospheric pressure), and the standard state of the atmosphere means an atmospheric pressure condition with a temperature near about 25°C and an absolute pressure near 101 kPa. Further, "normal pressure" includes cases where the pressure is slightly positive or negative with respect to the standard atmospheric pressure.

[0060] <SAM formation step> The SAM formation step S103 is a step of bringing a treatment liquid containing a SAM formation material into contact with the surface Wf of the substrate W to form a SAM.

[0061] The method of bringing the treatment liquid into contact with the substrate W is not particularly limited, and examples thereof include a method of applying the treatment liquid to the surface Wf of the substrate W, a method of spraying the treatment liquid onto the surface Wf of the substrate W, and a method of immersing the substrate W in the treatment liquid.

[0062] As a method of applying the treatment liquid to the surface Wf of the substrate W, for example, a method of supplying the treatment liquid to the central portion of the surface Wf of the substrate W while rotating the substrate W at a constant speed around its central portion can be mentioned. Thereby, the treatment liquid supplied to the surface Wf of the substrate W flows from near the center of the surface Wf of the substrate W toward the peripheral portion of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and is diffused over the entire surface Wf of the substrate W. As a result, the entire surface Wf of the substrate W is covered with the treatment liquid, and a liquid film of the treatment liquid is formed.

[0063] The conditions for bringing the treatment liquid into contact with the substrate W are not particularly limited. However, in the SAM formation step S103 of the present embodiment, the contact time of the treatment liquid can be shortened compared to the case of forming a SAM by a conventional method. Specifically, depending on the type of the SAM formation material, its concentration, the type of the solvent, etc., the time required for the SAM formation step S103 (immersion time when the substrate W is immersed in the treatment liquid) can be appropriately set within the range of 1 minute to 1540 minutes, preferably 1 minute to 60 minutes, more preferably 1 minute to 30 minutes.

[0064] Next, the formation process of the SAM will be described in more detail using the case where the SAM-forming material is octadecyltrichlorosilane as an example.

[0065] As shown in Fig. 2(a), when the treatment liquid is supplied to the surface Wf of the substrate W, in the treatment liquid at the beginning of the supply, SAM molecules 2 in which hydroxyl groups are introduced into octadecyltrichlorosilane are dispersed. Fig. 2(a) is a schematic diagram showing the state where the treatment liquid is supplied to the surface of the SiO2 layer 1 formed on the substrate W.

[0066] Next, when hydroxyl groups (OH groups) 3 are present on the surface of the SiO2 layer 1, the SAM molecules 2 undergo a dehydration condensation reaction with the hydroxyl groups 3 as shown in Fig. 2(b). More specifically, the hydroxyl group of the SAM molecule 2 and the hydroxyl group 3 on the surface of the SiO2 layer 1 undergo a dehydration condensation reaction to form a siloxane bond, whereby the SAM molecule 2 is chemisorbed on the surface of the SiO2 layer 1. The SAM molecules 2 are present in a state where aggregation with each other in the treatment liquid is suppressed. Therefore, in the film formation process of the SAM, the dehydration condensation reaction between the hydroxyl group of the SAM molecule 2 and the hydroxyl group 3 on the surface of the SiO2 layer 1, which is the rate-determining step, can be promoted. In addition, the SAM molecules 2 can be chemisorbed on the surface of the SiO2 layer 1 at a high density. Note that Fig. 2(b) is a schematic diagram showing the state where the SAM molecules 2 are chemisorbed on the surface of the SiO2 layer 1.

[0067] Subsequently, when the SAM molecules 2 are chemisorbed on the surface of the SiO2 layer 1 at a high density, an island structure of the SAM molecules 2 appears on the surface. Further, in each island, the SAM molecules 2 self-organize and grow (expand) due to hydrophobic interactions and electrostatic interactions between the SAM molecules 2, and finally the SAM 4 is formed (see Fig. 3(a)). Fig. 3(a) is a schematic diagram showing the state where the SAM molecules 2 self-organize on the surface of the SiO2 layer 1 to form the SAM 4.

[0068] <Removal step> The removal step S104 is a step of removing the processing liquid remaining on the surface of the SiO2 layer 1 after the SAM formation step S103. Thereby, surplus SAM molecules 2 that do not contribute to the formation of SAM4, more specifically, SAM molecules 2 that are not chemisorbed on the surface of the SiO2 layer 1 can be removed. As a result, the formation of a film composed of non-adsorbed SAM molecules 2 on SAM4 is prevented, and the formation of a good monomolecular film becomes possible. Also, in this step, neutralizing agents and salts generated by the reaction between by-products composed of acids or bases and the neutralizing agent can be removed.

[0069] The method for removing the processing liquid from the surface of the SiO2 layer 1 is not particularly limited, and examples thereof include a method of applying a removal liquid to the surface Wf of the substrate W, a method of spraying a removal liquid onto the surface Wf of the substrate W, and a method of immersing the substrate W in the removal liquid.

[0070] As a method of applying a removal liquid to the surface Wf of the substrate W, for example, a method can be mentioned in which the removal liquid is supplied to the central portion of the surface Wf of the substrate W while the substrate W is rotated at a constant speed about its central portion. Thereby, the removal liquid supplied to the surface Wf of the substrate W flows from the vicinity of the center of the surface Wf of the substrate W toward the peripheral portion of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and is diffused over the entire surface of the surface Wf of the substrate W. As a result, the processing liquid on the surface Wf of the substrate W is replaced with the removal liquid, and the entire surface of the surface Wf of the substrate W is covered with the removal liquid, and a liquid film of the removal liquid is formed.

[0071] When the SAM forming material is octadecyltrichlorosilane, the surface of the SiO2 layer 1 in the removal step S104 is as shown in FIG. 3(b). As shown in the figure, from the surface of the SiO2 layer 1 of the substrate W, SAM molecules 2 and the like that do not contribute to the film formation of SAM4 are removed by the removal liquid. FIG. 3(b) is an explanatory diagram showing a state in which surplus SAM molecules 2 are removed from the surface of the SiO2 layer 1 in the removal step S104.

[0072] The removal liquid is not particularly limited, but an organic solvent that dissolves the SAM forming material and has low solubility in water is preferred. If it is a removal liquid capable of dissolving the SAM forming material, excess SAM molecules 2 that do not contribute to the formation of SAM can be satisfactorily removed from the surface. More specifically, examples of the removal liquid include toluene, decane, 1,3-bis(trifluoromethyl)benzene, and the like. These solvents can be used alone or in combination of two or more.

[0073] <Drying process> The purpose of the drying process S105 is to remove the removal liquid remaining on the surface Wf of the substrate W. The drying method is not particularly limited, and examples include a method of spraying an inert gas such as nitrogen gas onto the surface Wf of the substrate W. The drying conditions such as the drying time and drying temperature are not particularly limited as long as the removal liquid is removed, and can be set as appropriate according to need.

[0074] As described above, in the substrate processing method of the present embodiment, as shown in FIG. 3(b), a SAM4 having excellent denseness and protective performance can be formed on the surface of the SiO2 layer 1. In the present embodiment, a treatment liquid containing a SAM molecule into which a hydroxyl group has been introduced in advance is used to form SAM4 on the surface of the SiO2 layer 1. At this time, since the treatment liquid also contains a neutralizing agent for neutralizing the acid or base by-products generated as by-products when introducing a hydroxyl group into the SAM molecule, the progress of the hydrolysis reaction for introducing a hydroxyl group is suppressed from being inhibited. As a result, since the treatment liquid contains SAM molecules into which hydroxyl groups have been sufficiently introduced without aggregating, the dehydration condensation reaction with the hydroxyl groups 3 on the surface of the SiO2 layer 1 can also occur efficiently, and it is possible to prevent the rate-determining step in the formation of SAM4. As a result, for dense film formation, it is possible to suppress the occurrence of film defects and efficiently form a SAM4 having excellent denseness and protective performance in a short time without allowing the SAM molecules 2 to contact the surface of the SiO2 layer 1 for a long time.

[0075] Furthermore, in the present embodiment, a rinsing step and another drying step may be further performed immediately after the drying step S105. By performing the rinsing step, the removal liquid can be removed from the surface of the SiO2 layer 1. Also, by performing another drying step, the rinsing liquid used in the rinsing step can be removed.

[0076] The rinsing liquid in the rinsing step is not particularly limited, and examples thereof include DIW and the like. The method for supplying the rinsing liquid to the surface Wf of the substrate W is not particularly limited, and examples thereof include a method of applying the rinsing liquid to the surface Wf of the substrate W, a method of spraying the rinsing liquid onto the surface Wf of the substrate W, and a method of immersing the substrate W in the rinsing liquid.

[0077] As a method of applying the rinsing liquid to the surface Wf of the substrate W, for example, a method is adopted in which the rinsing liquid is supplied to the central portion of the surface Wf of the substrate W while the substrate W is rotated at a constant speed about its central portion. As a result, the rinsing liquid supplied to the surface Wf of the substrate W flows from the vicinity of the center of the surface Wf of the substrate W toward the peripheral edge of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and is diffused over the entire surface of the surface Wf of the substrate W. As a result, the removal liquid on the surface Wf of the substrate W is replaced with the rinsing liquid, and the entire surface of the surface Wf of the substrate W is covered with the rinsing liquid, forming a liquid film of the rinsing liquid.

[0078] Another drying step is intended to remove the rinsing liquid remaining on the surface Wf of the substrate W. The drying method is not particularly limited, and examples thereof include a method of spraying an inert gas such as nitrogen gas onto the surface Wf of the substrate W. The drying conditions such as the drying time and the drying temperature are not particularly limited as long as the rinsing liquid is removed, and can be set as appropriate according to the need.

[0079] (Substrate processing apparatus) Next, the substrate processing apparatus according to the present embodiment will be described below with reference to the drawings. The substrate processing apparatus of the present embodiment can be applied to, for example, a semiconductor manufacturing apparatus for forming a three-dimensional structure such as a three-dimensional NAND structure on the surface of a substrate.

[0080] As shown in FIG. 4, the substrate processing apparatus 100 of the present embodiment is a single-wafer substrate processing apparatus used to form a SAM on the surface Wf of the substrate W. The substrate processing apparatus 100 includes at least a substrate holding unit 10 that holds the substrate W, a processing liquid generation unit 20 for generating a processing liquid, an ultrasonic application unit 30, a processing liquid supply unit 40 that supplies the processing liquid to the surface Wf of the substrate W, a removal liquid supply unit 50 for supplying a removal liquid, an inert gas supply unit 60 for supplying an inert gas, a chamber 70 that is a container for accommodating the substrate W, a splash prevention cup 80 that collects the processing liquid, a turning drive unit 90 that independently turns and drives the arms (described later) of each part of the substrate processing apparatus 100, and a control unit 200 for controlling each part of the substrate processing apparatus 100. Further, the substrate processing apparatus 100 may also include loading / unloading means (not shown) for loading or unloading the substrate W. Note that FIG. 4 is an explanatory diagram showing the schematic configuration of the substrate processing apparatus 100 according to the present embodiment. In this figure, for the sake of clarity of the illustrated directional relationship, the XYZ orthogonal coordinate axes are appropriately displayed. Here, the XY plane represents a horizontal plane, and the +Z direction represents the vertically upward direction.

[0081] <Substrate holding unit> The substrate holding unit 10 is a means for holding the substrate W. As shown in FIG. 4, the substrate holding unit 10 holds and rotates the substrate W in a substantially horizontal posture with the surface Wf of the substrate W facing upward. The substrate holding unit 10 has a spin chuck 13 in which a spin base 11 and a rotation support shaft 12 are integrally coupled. The spin base 11 has a substantially circular shape in plan view, and a hollow rotation support shaft 12 extending in a substantially vertical direction is fixed to the central portion thereof. The rotation support shaft 12 is connected to the rotation shaft of a chuck rotation mechanism 14 including a motor. The chuck rotation mechanism 14 is housed in a cylindrical casing 15, and the rotation support shaft 12 is rotatably supported by the casing 15 around the vertical rotation axis J.

[0082] The chuck rotation mechanism 14 can rotate the rotation support shaft 12 around the rotation axis J by the drive from the chuck drive unit (not shown) of the control unit 200. Thereby, the spin base 11 attached to the upper end portion of the rotation support shaft 12 rotates around the rotation axis J at a constant speed. The control unit 200 can control the chuck rotation mechanism 14 via the chuck drive unit to adjust the rotation speed of the spin base 11.

[0083] In the vicinity of the peripheral edge of the spin base 11, a plurality of chuck pins 16 for gripping the peripheral edge of the substrate W are erected. The number of the chuck pins 16 is not particularly limited, but in order to securely hold the circular substrate W, it is preferably provided with at least three or more. In the present embodiment, three are arranged at equal intervals along the peripheral edge of the spin base 11. Each chuck pin 16 includes a substrate support pin that supports the peripheral edge of the substrate W from below, and a substrate holding pin that presses the outer peripheral end surface of the substrate W supported by the substrate support pin to hold the substrate W.

[0084] <Processing liquid generation unit> The processing liquid generation unit 20 according to the present embodiment is a means for generating a processing liquid to be supplied to the surface Wf of the substrate W. As shown in FIG. 5, the processing liquid generation unit 20 includes an organic solvent supply unit 21, a water supply unit 22, a neutralizing agent supply unit 23, a SAM forming material supply unit 24, a processing liquid tank 25, a temperature adjustment unit 26, and an inert gas supply unit 27. Note that FIG. 5 is an explanatory diagram showing a schematic configuration of the processing liquid generation unit 20 and the ultrasonic application unit 30.

[0085] The organic solvent supply unit 21 includes an organic solvent storage unit 21a for storing an organic solvent, an organic solvent supply pipe 21b for supplying the organic solvent to the treatment liquid tank 25, and a valve 21c provided in the middle of the path of the organic solvent supply pipe 21b. Further, the valve 21c is electrically connected to the control unit 200. Thereby, the opening and closing of the valve 21c can be controlled by the operation command of the control unit 200. When the valve 21c is opened by the operation command of the control unit 200, the organic solvent is supplied to the treatment liquid tank 25 through the organic solvent supply pipe 21b. Incidentally, the organic solvent in the organic solvent storage unit 21a is pressurized by a pressurizing means (not shown) and sent to the organic solvent supply pipe 21b. Further, the pressurizing means is not particularly limited, and a known one such as a pump can be used.

[0086] The water supply unit 22 includes a water storage unit 22a for storing water, a water supply pipe 22b for supplying water to the treatment liquid tank 25, and a valve 22c provided in the middle of the path of the water supply pipe 22b. Further, the valve 22c is electrically connected to the control unit 200. Thereby, the opening and closing of the valve 22c can be controlled by the operation command of the control unit 200. When the valve 22c is opened by the operation command of the control unit 200, water is supplied to the treatment liquid tank 25 through the water supply pipe 22b. Incidentally, the water in the water storage unit 22a is pressurized by a pressurizing means (not shown) and sent to the water supply pipe 22b. Further, the pressurizing means is not particularly limited, and a known one such as a pump can be used.

[0087] The neutralizing agent supply unit 23 includes a neutralizing agent storage unit 23a for storing a neutralizing agent, a neutralizing agent supply pipe 23b for supplying the neutralizing agent to the treatment liquid tank 25, and a valve 23c provided in the middle of the path of the neutralizing agent supply pipe 23b. Further, the valve 23c is electrically connected to the control unit 200. Thereby, the opening and closing of the valve 23c can be controlled by the operation command of the control unit 200. When the valve 23c is opened by the operation command of the control unit 200, the neutralizing agent is supplied to the treatment liquid tank 25 through the neutralizing agent supply pipe 23b. Incidentally, the neutralizing agent in the neutralizing agent storage unit 23a is pressurized by a pressurizing means (not shown) and sent to the neutralizing agent supply pipe 23b. Further, the pressurizing means is not particularly limited, and a known one such as a pump can be used.

[0088] The SAM forming material supply unit 24 includes a SAM forming material storage unit 24a for storing a SAM forming material, a SAM forming material supply pipe 24b for supplying the SAM forming material to the treatment liquid tank 25, and a valve 24c provided in the middle of the path of the SAM forming material supply pipe 24b. Further, the valve 24c is electrically connected to the control unit 200. Thereby, the opening and closing of the valve 24c can be controlled by the operation command of the control unit 200. When the valve 24c is opened by the operation command of the control unit 200, the SAM forming material is supplied to the treatment liquid tank 25 through the SAM forming material supply pipe 24b. Incidentally, the SAM forming material in the SAM forming material storage unit 24a is pressurized by a pressurizing means (not shown) and sent to the SAM forming material supply pipe 24b. Further, the pressurizing means is not particularly limited, and a known one such as a pump can be used.

[0089] The treatment liquid tank 25 mixes the organic solvent supplied from the organic solvent supply unit 21, the water supplied from the water supply unit 22, and the neutralizing agent supplied from the neutralizing agent supply unit 23 to generate a dispersion liquid. Further, an ultrasonic application unit 30 is provided in the treatment liquid tank 25, whereby water can be uniformly dispersed in the dispersion liquid. Furthermore, the treatment liquid tank 25 can generate a treatment liquid by supplying the SAM forming material from the SAM forming material supply unit 24 in a state where the generated dispersion liquid is stored.

[0090] The processing liquid tank 25 may be provided with a temperature adjustment unit 26 for adjusting the temperature of the dispersion liquid or the processing liquid stored therein. The temperature adjustment unit 26 is electrically connected to the control unit 200. By the control unit 200 giving an operation command to the temperature adjustment unit 26, the liquid temperature of the dispersion liquid when generating the dispersion liquid can be controlled. Thereby, it is possible to prevent the water in the dispersion liquid from vaporizing (evaporating) and causing a change in the composition of the dispersion liquid.

[0091] The inert gas supply unit 27 includes an inert gas supply source 27a which is a supply source for supplying an inert gas into the processing liquid tank 25, a pump (not shown) for pressurizing the inert gas, an inert gas supply pipe 27b, and a valve 27c provided in the middle of the path of the inert gas supply pipe 27b.

[0092] The inert gas supply pipe 27b is connected to the processing liquid tank 25 through a pipeline. The valve 27c is electrically connected to the control unit 200, and the opening and closing of the valve 27c can be controlled by an operation command of the control unit 200. When the valve 27c is opened by an operation command of the control unit 200, the inert gas can be supplied to the processing liquid tank 25. Thereby, the generation of the dispersion liquid and the processing liquid can be carried out in an inert gas atmosphere. Note that the inert gas is not particularly limited, and for example, nitrogen gas etc. can be mentioned.

[0093] Furthermore, a discharge pipe 25a for supplying the processing liquid to the processing liquid supply unit 40 is connected to the processing liquid tank 25 through a pipeline. A discharge valve 25b is provided in the middle path of this discharge pipe 25a. Also, the discharge valve 25b is electrically connected to the control unit 200. Thereby, the opening and closing of the discharge valve 25b can be controlled by an operation command of the control unit 200. When the discharge valve 25b and the valve 27c are opened by an operation command of the control unit 200 and the valves 21c, 22c, 23c, and 24c are closed, the processing liquid is pumped to the processing liquid supply unit 40 through the discharge pipe 25a.

[0094] <Ultrasonic application unit> As shown in FIG. 5, the ultrasonic application unit 30 is a means for applying ultrasonic waves when generating a dispersion liquid in the treatment liquid tank 25 of the treatment liquid generation unit 20. The ultrasonic application unit 30 is electrically connected to the control unit 200, and the application of ultrasonic waves can be controlled by the operation command of the control unit 200.

[0095] The ultrasonic application unit 30 includes, for example, at least an ultrasonic vibrator provided in the treatment liquid tank 25 and an oscillator that applies a driving voltage to the ultrasonic vibrator (neither is shown). Examples of the ultrasonic vibrator include those including a piezoelectric body such as piezoelectric ceramics and a pair of electrodes provided on the piezoelectric body. The pair of electrodes is in contact with the piezoelectric body and is also electrically connected to the oscillator. When the oscillator outputs, as a driving voltage, for example, a high-frequency voltage to the ultrasonic vibrator in response to the operation command of the control unit 200, a driving voltage is applied between the pair of electrodes, and the driving voltage is applied to the piezoelectric body. The piezoelectric body to which the driving voltage is applied vibrates by alternately repeating contraction and expansion in response to the driving voltage from the oscillator. Thereby, ultrasonic waves can be applied to at least the organic solvent added with water stored in the treatment liquid tank 25.

[0096] <Treatment liquid supply unit> The treatment liquid supply unit 40 according to the present embodiment is a means for supplying a treatment liquid to the surface Wf of the substrate W. As shown in FIG. 4, the treatment liquid supply unit 40 has a nozzle 41 and an arm 42.

[0097] The nozzle 41 is connected to the discharge pipe 25a through a pipeline and is attached to the tip of the horizontally extending arm 42. When discharging the treatment liquid supplied from the treatment liquid tank 25, the nozzle 41 is disposed above the spin base 11. The arm 42 is connected to the swing drive unit 90 via a swing shaft (not shown). The swing drive unit 90 is electrically connected to the control unit 200 and rotates the arm 42 according to the operation command from the control unit 200. As the arm 42 rotates, the nozzle 41 also moves.

[0098] <Removal liquid supply unit> The removal liquid supply unit 50 according to this embodiment is a means for supplying a removal liquid to the surface Wf of the substrate W. As shown in FIG. 4, this removal liquid supply unit 50 has a removal liquid storage unit 51, a nozzle 52, and an arm 53.

[0099] As shown in FIG. 6, the removal liquid storage unit 51 has a function of supplying the removal liquid to the nozzle 52, and includes a pressurizing unit 54 and a removal liquid tank 55. FIG. 6 is an explanatory diagram showing a schematic configuration of the removal liquid storage unit 51 in the removal liquid supply unit 50.

[0100] The pressurizing unit 54 includes a nitrogen gas supply source 54a which is a supply source of gas for pressurizing the inside of the removal liquid tank 55, a pump (not shown) for pressurizing the nitrogen gas, a nitrogen gas supply pipe 54b, and a valve 54c provided in the middle of the path of the nitrogen gas supply pipe 54b.

[0101] The nitrogen gas supply pipe 54b is connected to the removal liquid tank 55 through a pipeline. The valve 54c is electrically connected to the control unit 200, and the opening and closing of the valve 54c can be controlled by an operation command of the control unit 200. When the valve 54c is opened by an operation command of the control unit 200, nitrogen gas can be supplied to the removal liquid tank 55.

[0102] The removal liquid tank 55 may include a stirring unit for stirring the removal liquid in the removal liquid tank 55 and a temperature adjusting unit for adjusting the temperature of the removal liquid (both are not shown). Examples of the stirring unit include a rotating unit for stirring the removal liquid in the removal liquid tank 55 and a stirring control unit for controlling the rotation of the rotating unit. The stirring control unit is electrically connected to the control unit 200, and the rotating unit is provided with, for example, a propeller-shaped stirring blade at the lower end of the rotating shaft. When the control unit 200 issues an operation command to the stirring control unit, the rotating unit is rotated, and thereby the removal liquid can be stirred by the stirring blade. As a result, the concentration and temperature of the removal liquid can be made uniform in the removal liquid tank 55.

[0103] Further, a discharge pipe 55a for supplying the removal liquid to the nozzle 52 is connected to the removal liquid tank 55 through a pipeline. A discharge valve 55b is provided in the middle path of the discharge pipe 55a. The discharge valve 55b is electrically connected to the control unit 200. Thus, the opening and closing of the discharge valve 55b can be controlled by the operation command of the control unit 200. When the discharge valve 55b is opened by the operation command of the control unit 200, the removal liquid is pumped to the nozzle 52 through the discharge pipe 55a.

[0104] The nozzle 52 is attached to the tip of an arm 53 extending horizontally, and is disposed above the spin base 11 when discharging the removal liquid. The arm 53 is connected to a turning drive unit 90 via a turning axis (not shown). The turning drive unit 90 is electrically connected to the control unit 200, and rotates the arm 53 according to an operation command from the control unit 200. As the arm 53 rotates, the nozzle 52 also moves.

[0105] <Inert gas supply unit> The inert gas supply unit 60 is a means for supplying an inert gas to the surface Wf of the substrate W. As shown in FIG. 4, the inert gas supply unit 60 includes an inert gas storage unit 61, a nozzle 62, and an arm 63.

[0106] As shown in FIG. 7, the inert gas storage unit 61 has a function of supplying an inert gas to the nozzle 62, and includes an inert gas tank 64 for storing the inert gas, an inert gas temperature adjustment unit 65 for adjusting the temperature of the inert gas stored in the inert gas tank 64, a pipe 66, and a valve 67. Examples of the inert gas stored in the inert gas tank 64 include nitrogen gas. Note that FIG. 7 is a block diagram showing a schematic configuration of the inert gas storage unit 61 in the inert gas supply unit 60.

[0107] The inert gas temperature adjustment unit 65 is electrically connected to the control unit 200, and performs temperature adjustment by heating or cooling the inert gas stored in the inert gas tank 64 according to the operation command of the control unit 200. The inert gas temperature adjustment unit 65 is not particularly limited, and for example, a known temperature adjustment mechanism such as a Peltier element or a pipe through which temperature-adjusted water passes can be used.

[0108] The inert gas storage unit 61 is connected to the nozzle 62 through the pipe 66, and a valve 67 is inserted in the middle of the path of the pipe 66. The inert gas in the inert gas tank 64 is pressurized by a pressurizing means (not shown) and sent to the pipe 66. In addition, the pressurizing means can be realized not only by pressurizing with a pump or the like, but also by compressing and storing the inert gas in the inert gas tank 64.

[0109] The valve 67 is electrically connected to the control unit 200 and is normally closed. The opening and closing of the valve 67 are controlled by the operation command of the control unit 200. When the valve 67 is opened by the operation command of the control unit 200, the inert gas is supplied from the nozzle 62 to the surface Wf of the substrate W through the pipe 66.

[0110] The nozzle 62 is attached to the tip of the horizontally extending arm 63, and is disposed above the spin base 11 when discharging the inert gas. The arm 63 is connected to the swing drive unit 90 via a swing shaft (not shown). The swing drive unit 90 is electrically connected to the control unit 200 and rotates the arm 63 according to the operation command from the control unit 200. As the arm 63 rotates, the nozzle 62 also moves.

[0111] <Scattering prevention cup> The splash prevention cup 80 is provided so as to surround the spin base 11. The splash prevention cup 80 is connected to a lifting drive mechanism (not shown) and is capable of moving up and down in the vertical direction. When supplying a processing liquid or the like to the surface Wf of the substrate W, the splash prevention cup 80 is positioned at a predetermined position by the lifting drive mechanism and surrounds the substrate W held by the chuck pin 16 from the side position. Thereby, it is possible to collect the processing liquid or the like scattered from the substrate W and the spin base 11.

[0112] <Control unit> The control unit 200 is electrically connected to each part of the substrate processing apparatus 100 and controls the operation of each part. The control unit 200 is constituted by a computer having an arithmetic unit and a storage unit. As the arithmetic unit, a CPU that performs various arithmetic processes is used. Further, the storage unit includes a read-only memory ROM that stores a substrate processing program and an etching processing program, a random access memory RAM that stores various information and is readable and writable, and a magnetic disk that stores control software, data, and the like. The magnetic disk stores in advance processing conditions including the generation (mixing) conditions of the dispersion liquid and the processing liquid; the supply conditions of the processing liquid, the removal liquid, and the inert gas; the application conditions of ultrasonic waves; the rinsing conditions; the drying conditions; and the film formation conditions of SAM. The CPU reads the processing conditions into the RAM and controls each part of the substrate processing apparatus 100 according to the content.

[0113] (Other matters) In the above description, the most preferred embodiment of the present invention has been described. However, the present invention is not limited to the embodiment. Each configuration in the above-described embodiment and each modification can be changed, modified, replaced, added, deleted, and combined within a range that does not conflict with each other.

Description of reference numerals

[0114] 1 SiO2 layer 2 SAM (self-assembled monolayer) molecules 3 Hydroxyl group 4 SAM (self-assembled monolayer) 10 Substrate holding part 20 Processing liquid generation part 21 Organic solvent supply section 21a Organic solvent storage section 21b Organic solvent supply pipe 21c Valve 22 Water supply section 22a Water storage section 22b Water supply pipe 22c Valve 23 Neutralizing agent supply section 23a Neutralizing agent storage section 23b Neutralizing agent supply pipe 23c Valve 24 SAM (Self-assembled monolayer) forming material supply section 24a SAM (Self-assembled monolayer) forming material storage section 24b SAM (Self-assembled monolayer) forming material supply pipe 24c Valve 25 Treatment liquid tank 25a Drain pipe 25b Drain valve 26 Temperature adjustment section 27a Inert gas supply source 27b Inert gas supply pipe 27c Valve 27 Inert gas supply section 30 Ultrasonic application section 40 Treatment liquid supply section 41 Nozzle 42 Arm 50 Removing liquid supply section 60 Inert gas supply section 70 Chamber 80 Splash prevention cup 90 Rotary drive section 100 Substrate processing apparatus 200 Control section S101 Dispersion liquid generation process S102 Treatment liquid generation process S103 SAM (Self-assembled monolayer) formation process (film formation process) S104 Removal process S105 Drying process W Substrate Wf Surface of the substrate

Claims

1. A substrate processing method for forming a self-assembled monolayer on the surface of a substrate, comprising: a dispersion liquid generation step of generating a dispersion liquid containing water, a neutralizing agent, and an organic solvent as a main solvent, and in which the water is dispersed; a treatment liquid generation step of adding a material containing a molecule having a functional group exhibiting hydrolysis reactivity and capable of forming the self-assembled monolayer to the dispersion liquid to generate a treatment liquid; a film formation step of forming the self-assembled monolayer by supplying the treatment liquid to the surface of the substrate; wherein in the treatment liquid generation step, a hydrolysis reaction is caused between the water dispersed in the dispersion liquid and the functional group to generate the molecule in a state having a hydroxyl group, and the acid or base generated by the hydrolysis reaction is neutralized by the neutralizing agent. A substrate processing method.

2. As the neutralizing agent, those having δp (MPa １／２ ), and δh (MPa １／２ ) satisfying the following relational expressions (1) and (2) are used. The substrate processing method according to claim 1 δp １ <δp<δp ２ (1) (wherein, δp １ (MPa １／２ ) represents the polar term in the Hansen solubility parameter of the organic solvent, and δp ２ (MPa １／２ ) represents the polar term in the Hansen solubility parameter of a molecule having a functional group exhibiting the hydrolytic reactivity and capable of forming the self-assembled monolayer.) δh １ <δh<δh ２ (2) (wherein, δh １ (MPa １／２ ) represents the hydrogen bonding term in the Hansen solubility parameter of the organic solvent, and δh ２ (MPa １／２ ) represents the hydrogen bonding term in the Hansen solubility parameter of a molecule having a functional group exhibiting the hydrolytic reactivity and capable of forming the self-assembled monolayer.)

3. In the treatment liquid generation step, when the acid is generated by the hydrolysis reaction, an amine compound satisfying the relational expressions (1) and (2) is used as the neutralizing agent. The substrate processing method according to Claim 2.

4. The substrate processing method according to Claim 3, wherein the amine compound is at least one selected from the group consisting of trimethylamine, triethylamine, and diisopropylamine.

5. The dispersion liquid generation step is a step of dispersing the water in the organic solvent by mixing at least the water with the organic solvent while applying ultrasonic waves, or by applying ultrasonic waves after mixing at least the water with the organic solvent. The substrate processing method according to any one of Claims 1 to 4.

6. A substrate processing apparatus for forming a self-assembled monolayer on the surface of a substrate, comprising: a treatment liquid generation unit for generating a treatment liquid containing a molecule capable of forming the self-assembled monolayer; a treatment liquid supply unit for forming the self-assembled monolayer by supplying the treatment liquid generated by the treatment liquid generation unit to the surface of the substrate; wherein the treatment liquid generation unit generates a dispersion liquid containing water, a neutralizing agent, and an organic solvent as a main solvent, and in which the water is dispersed in the organic solvent, and then By adding a material containing a molecule having a functional group exhibiting hydrolysis reactivity and capable of forming the self-assembled monolayer to the dispersion liquid, the water contained in the dispersion liquid and the functional group are caused to undergo a hydrolysis reaction to generate the molecule in a state having a hydroxyl group, and an acid or base generated by the hydrolysis reaction is neutralized with the neutralizing agent to generate the treatment liquid. Substrate processing apparatus.

7. As the neutralizing agent, use one in which δp (MPa １／２ ), and δh (MPa １／２ ) satisfy the following relational expressions (1) and (2). The substrate processing apparatus according to claim 6 δp １ <δp<δp ２ (1) (wherein, δp １ (MPa １／２ ) represents the polar term in the Hansen solubility parameter of a molecule having a functional group exhibiting the hydrolysis reactivity and capable of forming the self-assembled monolayer, and δp ２ (MPa １／２ ) represents the polar term in the Hansen solubility parameter of the organic solvent.) δh １ <δh<δh ２ (2) (wherein δh １ (MPa １／２ ) represents the hydrogen bonding term in the Hansen solubility parameter of a molecule having a functional group exhibiting the hydrolysis reactivity and capable of forming the self-assembled monolayer, and δh ２ (MPa １／２ ) represents the hydrogen bonding term in the Hansen solubility parameter of the organic solvent.)

8. The substrate processing apparatus according to claim 7, wherein when the acid is generated by the hydrolysis reaction, the treatment liquid generation unit uses an amine compound satisfying the relational expressions (1) and (2) as the neutralizing agent.

9. The substrate processing apparatus according to claim 8, wherein the amine compound is at least one selected from the group consisting of trimethylamine, triethylamine, and diisopropylamine.

10. The substrate processing apparatus according to any one of claims 6 to 9, further comprising an ultrasonic application unit that disperses the water in the organic solvent by mixing at least the water with the organic solvent while applying ultrasonic waves, or by applying ultrasonic waves after mixing at least the water with the organic solvent.

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