Patterned substrate prewetting composition, resist pattern manufacturing method, processed substrate manufacturing method, and device manufacturing method

Abstract

To form an underlayer film on a pattern substrate with good coverage. [Solution] The pattern substrate prewet composition has a vapor pressure of 0.05 to 40 mmHg at 20°C and a surface tension of 15 to 60 dyn / cm at 20°C. The viscosity of the pattern substrate prewet composition may be 0.5 to 20.0 cP. The pattern substrate prewet composition contains an organic solvent (A), and optionally, the organic solvent (A) may be one type of organic solvent or a mixture of two or more types of organic solvents.

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a patterned substrate prewetting composition, a method for producing a resist pattern, a method for producing a processed substrate, and a method for producing a device. [Background technology]

[0002] In the manufacture of devices (electronic components) such as semiconductor devices and liquid crystal display devices, an underlayer film such as an anti-reflective film may be formed before forming a resist film in order to prevent poor resolution due to reflection from the substrate during the photolithography process (particularly the exposure process). Patent Document 1 discusses a technique in which the thermal curing of a coating film is promoted from the portion near the substrate by heating, and the heating is stopped before the entire film is cured, and the uncured portion is removed with a solvent. Patent Document 2 discusses a technique in which a solution of a resist composition is used as a prewetting agent. Patent Document 3 discusses a prewetting liquid for resist containing cyclohexanone and a compound with a specific structure in a certain mass ratio. Patent Document 4 discusses a prewetting liquid for resist that satisfies specified surface tension, viscosity, and vapor pressure as a prewetting liquid with excellent resist-saving properties. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-320807 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-39828 [Patent Document 3] International Publication No. 2020 / 170742 [Patent Document 4] International Publication No. 2021 / 059862 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Documents 2, 3, and 4 discuss a prewetting agent to be used immediately before applying the resist composition, but do not consider application to uneven substrates. Depending on the shape of the substrate (for example, in the case of a patterned substrate on which a pattern has been formed in advance), it may not be possible to form an underlayer film formed under the resist film with good coverage on the substrate surface.

[0005] In view of the above problems, the present invention has as its object at least one of the following: to form an underlayer film on a patterned substrate with good coverage; to form an underlayer film on a patterned substrate with good conformality; to suppress variations in the resist pattern between areas affected by standing waves and areas not affected; to suppress the yield of an element manufacturing method; to provide a patterned substrate prewet composition with sufficient storage stability; to prevent cracks from occurring in the underlayer film; to have volatility suitable for application of the underlayer film; and to have good wettability to the patterned substrate surface. [Means for solving the problem]

[0006] According to one embodiment of the present invention, there is provided a pattern substrate prewetting composition having a vapor pressure at 20°C of 0.05 to 40 mmHg and a surface tension at 20°C of 15 to 60 dyn / cm. According to one embodiment of the present invention, there is provided a use of a pre-wet composition for application directly onto a patterned substrate. According to one embodiment of the present invention, there is provided a method for producing a resist pattern, comprising: preparing a patterned substrate; applying a patterned substrate pre-wet composition directly onto the patterned substrate; applying an underlayer film composition onto the patterned substrate to form an underlayer film; optionally heating the underlayer film; forming a resist film directly onto the underlayer film; and processing the resist film to form a resist pattern. According to one embodiment of the present invention, there is provided a method for producing a processed substrate, comprising producing a resist pattern by the above-described method, and performing processing using the resist pattern as a mask. According to one embodiment of the present invention, there is provided a method for manufacturing a device, which includes the above-described method for manufacturing a processed substrate. [Effects of the Invention]

[0007] By using one embodiment of the present invention, an underlayer film can be formed on a patterned substrate with good coverage. By using one embodiment of the present invention, an underlayer film can be formed on a patterned substrate with good conformality. By using one embodiment of the present invention, the yield of the resist pattern can be improved. By using one embodiment of the present invention, the variation between areas of the resist pattern affected by standing waves and areas not affected can be suppressed. By using one embodiment of the present invention, the yield of the element manufacturing method can be suppressed. By using one embodiment of the present invention, a patterned substrate prewetting composition having sufficient storage stability can be provided. By using one embodiment of the present invention, the occurrence of cracks in the underlayer film can be prevented. By using one embodiment of the present invention, the composition can have volatility suitable for coating the underlayer film. By using one embodiment of the present invention, the composition can have good wettability to the patterned substrate surface. [Brief explanation of the drawings]

[0008] [Figure 1A] 1A to 1C are schematic cross-sectional views illustrating a method for producing a resist pattern according to one embodiment of the present invention. [Figure 1B] 1A to 1C are schematic cross-sectional views illustrating a method for producing a resist pattern according to one embodiment of the present invention. [Figure 1C] 1A to 1C are schematic cross-sectional views illustrating a method for producing a resist pattern according to one embodiment of the present invention. [Figure 1D] 1A to 1C are schematic cross-sectional views illustrating a method for producing a resist pattern according to one embodiment of the present invention. [Figure 1E] 1A to 1C are schematic cross-sectional views illustrating a method for producing a resist pattern according to one embodiment of the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view after forming an underlayer film according to one embodiment of the present invention. [Figure 3] FIG. 10 is a schematic cross-sectional view for evaluating conformality. [Figure 4] 1 is an SEM photograph of an example of a patterned substrate on which an underlayer film is formed, which is rated A in an example of the present invention. [Figure 5] 1 is a SEM photograph of an example of a patterned substrate on which an underlayer film is formed, which is rated C in an example of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, the patterned substrate prewet composition, the method for producing a resist pattern, the method for producing a processed substrate, and the method for producing a device according to each embodiment of the present invention will be described in detail with reference to the drawings. Note that each embodiment shown below is an example of an embodiment of the present invention, and the present invention should not be construed as being limited to these embodiments. In addition, in the drawings attached to this specification, the shape, scale, aspect ratio, etc. of each part may be changed from the actual product or may be exaggerated in order to make it easier to understand.

[0010] [Definition] In this specification, unless otherwise specified, the definitions and examples set forth in this paragraph shall be followed. The singular includes the plural, and "one" and "the" mean "at least one." An element of a concept can be expressed by a plurality of species, and when an amount thereof (e.g., mass % or mole %) is stated, the amount refers to the sum of the plurality of species. "And / or" includes all combinations of elements as well as any single element. When a numerical range is indicated using "~" or "-", it includes both endpoints and the units are the same. For example, 5 to 25 mol % means 5 mol % or more and 25 mol % or less. Designations such as "Cx-y," "Cx-Cy," and "Cx" refer to the number of carbons in a molecule or substituent. For example, C1-6 alkyl refers to an alkyl chain having from 1 to 6 carbons (e.g., methyl, ethyl, propyl, butyl, pentyl, hexyl, etc.). When a polymer has multiple types of repeating units, these repeating units are copolymerized. This copolymerization may be alternating copolymerization, random copolymerization, block copolymerization, graft copolymerization, or a mixture of these. When polymers or resins are represented by structural formulas, the n or m in parentheses indicates the repeating number. The temperature unit is Celsius. For example, 20°C means 20°C.

[0011] In this specification, the term "patterned substrate" refers to a substrate on which a pattern having a predetermined shape is formed in advance. Therefore, the term "pattern" in this specification refers to a pattern formed by processing the surface of a substrate, and preferably does not include a pattern formed from another film or layer on the substrate. For example, it is preferable that a resist pattern consisting only of an organic substance is formed on a bare wafer not be included in the term "pattern." However, a substrate in which a metal film, an oxide film, or a nitride film is deposited on a flat substrate and processed to the extent that the flat substrate is not exposed is also included in the term "patterned substrate." The surface of the substrate before processing may be treated by oxidizing or nitriding the metal.

[0012] In this specification, the term "pattern substrate prewet composition" refers to a composition that is applied to the top surface of a substrate pattern and into the gaps (also called spaces) between patterns, and it is more preferable to form an underlayer film thereafter.

[0013] In this specification, "conformality" means that when a substrate having a pattern with a pattern width of 500 nm / space width of 500 nm and a height of 100 nm is used, the ratio (X / Y) of the film thickness (X) of the underlayer film at the top of the substrate pattern wall to the film thickness (Y) of the underlayer film at the bottom of the groove between the pattern walls is 0.20 to 0.99.

[0014] In this specification, "coverability" means that when a substrate having a pattern with a pattern width of 500 nm / space width of 500 nm and a height of 100 nm is used, the distance from the corner (upper end) of the upper part of the pattern wall to the end of the underlying film at the upper part of the pattern wall is 0 to 70 nm.

[0015] [1. Patterned substrate pre-wetting composition] The patterned substrate prewet composition according to one embodiment of the present invention has a vapor pressure at 20°C of 0.05 to 40 mmHg, preferably 0.5 to 40 mmHg, more preferably 1 to 30 mmHg, even more preferably 1 to 20 mmHg, and even more preferably 1.3 to 8 mmHg. The patterned substrate prewet composition also has a surface tension at 20°C of 15 to 60 dyn / cm, preferably 22 to 47 dyn / cm, more preferably 22 to 30 dyn / cm, and even more preferably 23 to 28 dyn / cm. The patterned substrate prewet composition is preferably used immediately before the formation of an underlayer film. The underlayer film refers to a film formed on a substrate beneath a resist film. The underlayer film is preferably a bottom antireflective coating (BARC), a planarizing film, an adhesion-enhancing film, or a high-carbon film (SOC) (more preferably a BARC or SOC; even more preferably a BARC). Each component of the patterned substrate prewet composition is described below.

[0016] The patterned substrate prewet composition according to one embodiment of the present invention has a viscosity at 20°C of 0.5 to 20.0 cP, preferably 0.7 to 18 cP, more preferably 1.0 to 15 cP, and even more preferably 1.2 to 12 cP.

[0017] A patterned substrate prewetting composition according to one embodiment of the present invention contains an organic solvent (A). The organic solvent (A) is preferably one type of organic solvent or a mixture of two or more types of organic solvents. Specifically, the organic solvent (A) is preferably one selected from the group consisting of alcohol solvents, ether solvents, ester solvents, ketone solvents, and hydrocarbon solvents, or any combination thereof.

[0018] When an alcohol solvent is used as the organic solvent (A), the alcohol solvent is preferably n-propanol, i-propanol (IPA), n-butanol, i-butanol, sec-butanol, t-butanol, n-pentanol, i-pentanol, 2-methylbutanol, sec-pentanol, t-pentanol, 3-methoxybutanol, or n-hexanol.

[0019] When an ether solvent is used as the organic solvent (A), the ether solvent is preferably a propylene glycol monoalkyl ether such as propylene glycol monomethyl ether (PGME), ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, or propylene glycol monoethyl ether (PGEE), dibutyl ether, or dioxane.

[0020] When an ester solvent is used as the organic solvent (A), the ester solvent is preferably methyl lactate, ethyl lactate (EL), γ-butyrolactone, n-propyl acetate, n-butyl acetate, i-butyl acetate, sec-butyl acetate, n-pentyl acetate, or propylene glycol 1-monomethyl ether 2-acetate (PGMEA).

[0021] When a ketone solvent is used as the organic solvent (A), the ketone solvent is preferably 2-pentanone, 3-pentanone, methyl isobutyl ketone, 2-heptanone, 2-hexanone, 4-heptanone, diisobutyl ketone, cyclopentanone, or cyclohexanone.

[0022] When a hydrocarbon solvent is used as the organic solvent (A), the hydrocarbon solvent is preferably toluene, heptane, octane, methylcyclohexane, or ethylcyclohexane.

[0023] The organic solvent (A) of the present invention is preferably an ether solvent, an ester solvent, or a mixture thereof (more preferably an ether solvent or an ester solvent). The organic solvent (A) is preferably PGME, EL, n-butanol, butyl acetate, cyclopentanone, toluene, n-pentanol, n-hexanol, or a mixture of any of these, more preferably PGME, EL, n-pentanol, n-hexanol, or a mixture of any of these, even more preferably PGME, EL, or a mixture of any of these, and even more preferably PGME or EL. When the organic solvent (A) is a mixture of two compounds, the volume ratio is preferably 95:5 to 5:95, more preferably 90:10 to 10:90, even more preferably 80:20 to 20:80, and still more preferably 70:30 to 30:70. The content of the organic solvent (A) in the patterned substrate prewet composition is preferably 95 to 100 mass %, more preferably 97 to 100 mass %, and even more preferably 99 to 100 mass %, based on the total mass of the patterned substrate prewet composition. It is even more preferable that the patterned substrate prewet composition consists essentially of the organic solvent (A).

[0024] The pattern substrate prewet composition may further contain an additive (B). The additive (B) is a compound different from the component (A). The additive (B) is preferably highly volatile. Specifically, the additive (B) preferably evaporates when the organic solvent (A) evaporates, or around the time, but not limited to, the additive (B). The content of the additive (B) in the pattern substrate prewet composition is 0 to 5 mass %, preferably 0 to 3 mass %, and more preferably 0 to 1 mass %, based on the total weight of the pattern substrate prewet composition. In one embodiment of the present invention, the content of the additive (B) in the pattern substrate prewet composition may of course include an embodiment in which the additive (B) is not contained (0 mass %) based on the total weight of the pattern substrate prewet composition, and it is desirable that the pattern substrate prewet composition does not contain the additive (B).

[0025] The additive (B) may be selected from a surfactant, an acid, a base, a substrate adhesion promoter, an antifoaming agent, or any combination thereof. The additive (B) will be specifically described below.

[0026] (surfactant) The pattern substrate pre-wet composition contains a surfactant as additive (B), which improves the coating properties of the composition. The content of the surfactant in the pattern substrate pre-wet composition is 0 to 2 mass %, preferably 0 to 1 mass %, and more preferably 0 to 0.5 mass %, relative to the organic solvent (A).

[0027] Any surfactant can be used. For example, an anionic surfactant, a cationic surfactant, or a nonionic surfactant can be used. More specifically, alkyl sulfonates, alkyl benzene sulfonic acids, alkyl benzene sulfonates, lauryl pyridinium chloride, lauryl methyl ammonium chloride, polyoxyethylene octyl ether, polyoxyethylene lauryl ether, or polyoxyethylene acetylenic glycol ether is preferably used as the surfactant. Nonionic surfactants include nonionic alkyl ether surfactants manufactured by Nippon Nyukazai Co., Ltd., and the like, which are commercially available.

[0028] (acid or base) The inclusion of an acid or base as additive (B) can improve the properties of the patterned substrate prewet composition, such as by adjusting the pH of the patterned substrate prewet composition. The acid or base may be prepared according to the material of the substrate to which the patterned substrate prewet composition is to be applied, and added to the patterned substrate prewet composition. The content of the acid or base in the patterned substrate prewet composition is 0 to 1 mass %, preferably 0 to 0.5 mass %, and more preferably 0 to 0.2 mass %, relative to the organic solvent (A).

[0029] The acid or base can be selected arbitrarily as long as it does not impair the effects of the present invention. For example, carboxylic acids, amines, or ammonium salts can be used as the acid or base. The carboxylic acids, amines, or ammonium salts herein include fatty acids, aromatic carboxylic acids, primary amines, secondary amines, tertiary amines, or ammonium compounds, which may be substituted with any substituent. More specifically, the acid or base can be formic acid, acetic acid, propionic acid, benzoic acid, phthalic acid, salicylic acid, lactic acid, malic acid, citric acid, oxalic acid, malonic acid, succinic acid, fumaric acid, maleic acid, aconitic acid, glutaric acid, adipic acid, monoethanolamine, diethanolamine, triethanolamine, triisopropanolamine, or tetramethylammonium.

[0030] In a patterned substrate pre-wetting composition according to one embodiment of the present invention, the patterned substrate comprises two adjacent patterns and a space between the at least two patterns. In FIG. 1A, when the pattern width L is the length in the short direction of the top of the pattern 11a (the diameter in the case of circular dots) and the space width S is the distance between the pattern bottoms of adjacent patterns 11a, the ratio of the pattern width L to the space width S (L / S) is preferably 1 / 100 to 100, preferably 1 / 20 to 20, more preferably 1 / 10 to 10, and even more preferably 1 / 5 to 5.

[0031] Furthermore, L / S may be varied depending on the pattern shape. Specifically, when the pattern substrate 11 has a line-and-space pattern, it is preferable that the pattern width L≦space width S, and in one embodiment, L / S is 1 / 10 to 1, preferably 1 / 5 to 1. When the pattern substrate has a slit-shaped pattern, it is preferable that the pattern width L≧space width S, and in one embodiment, L / S is 1 to 10, preferably 15. When the pattern substrate has a dot-shaped pattern, it is preferable that the pattern width L≦space width S, and in one embodiment, L / S is 1 / 100 to 1, preferably 1 / 20 to 1.

[0032] The mechanism of the patterned substrate pre-wetting composition having the above-mentioned configuration is not limited to a particular theory, but is presumed to be as follows. It is believed that the pattern substrate prewet composition of the present invention has a surface tension of a certain level or higher, which prevents the underlayer film composition applied to the upper part of the pattern wall of the substrate pattern from being too attracted to the prewet composition and dropping between the pattern walls.Furthermore, it is believed that the surface tension of the pattern substrate prewet composition is a certain level or lower, which prevents the underlayer film composition applied to the upper part of the pattern wall of the substrate pattern from being repelled by the prewet composition and dropping from the upper part of the pattern. It is believed that the vapor pressure of the patterned substrate prewet composition of the present invention is within a certain range, which allows an appropriate amount of the prewet composition to remain on the substrate pattern when the underlayer film composition is applied. For the above reasons, it is believed that by using the patterned substrate composition of the present invention, good coverage and conformality of the underlayer film composition on the patterned substrate can be achieved.

[0033] 2. Use of Pre-Wet Composition In one embodiment of the present invention, in the use of a pre-wet composition for application directly onto a patterned substrate, the vapor pressure of the pre-wet composition at 20° C. may be the same as the vapor pressure of the above-described patterned substrate pre-wet composition at 20° C. Similarly, the surface tension may be the same as the surface tension of the above-described patterned substrate pre-wet composition at 20° C.

[0034] [3. Resist Pattern Manufacturing Method] 1A to 1E, the use of a patterned substrate pre-wetting composition according to one embodiment of the present invention will be described.

[0035] 1A, first, a patterned substrate 11 is prepared. The patterned substrate 11 includes a pattern 11a and a portion 11b that serves as a base for the pattern 11a, and the pattern 11a and the portion 11b that serves as a base are made of the same material and are integrated together. The method for forming the pattern 11a on the patterned substrate 11 can be arbitrarily selected from known methods such as photolithography and dry etching. In forming the pattern 11a, various pretreatments can be combined.

[0036] The shape of the patterned substrate 11 is not particularly limited, and the patterned substrate 11 may have a pattern of any shape, such as lines and spaces, slits, or dots. The dots refer to a columnar shape, and may be a quadrangular column or a cylindrical column. The height H of the pattern 11a (the vertical distance from the bottom to the top surface of the pattern) is desirably 0.01 to 300 μm, preferably 0.01 to 200 μm, and more preferably 0.01 to 150 μm. When the pattern width L is the length in the short direction of the upper part of the pattern (the diameter in the case of circular dots), the aspect ratio (L / H) of the pattern width L to the pattern height H is preferably 1 / 100 to 100, preferably 1 / 20 to 20, more preferably 1 / 10 to 10, even more preferably 1 / 5 to 5, and even more preferably 1 to 5. If the pattern width L is the short-side length of the top of the pattern 11a (the diameter in the case of a circular dot), and the space width S is the distance between the pattern bottoms of adjacent patterns 11a, the ratio (L / S) of the pattern width L to the space width S may be the L / S in the pattern substrate prewet composition described above, and as described above, the L / S may be changed depending on the pattern shape.

[0037] The patterned substrate 11 may be made of any of a semiconductor, an oxide, a nitride, a metal, or a combination thereof. Therefore, the material of the patterned substrate 11 is not particularly limited, but may be, for example, Ge, SiGe, SiO2, TiO2, Al2O3, SiON, HfO2, Ta2O5, HfSiO4, Y2O3, GaN, TiN, TaN, Si3N4, NbN, Cu, Ta, W, Hf, or Al. The patterned substrate 11 may have a structure in which multiple layers are stacked. In this example, the patterned substrate 11 may have an oxide layer formed on a semiconductor. In this case, the pattern may be formed on the oxide layer provided on the silicon substrate.

[0038] The patterned substrate 11 may be a glass substrate for a liquid crystal display device, a glass substrate for an organic EL display device, a glass substrate for a plasma display, a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, a glass substrate for a photomask, or a substrate for a solar cell, etc.

[0039] Next, as shown in FIG. 1B, a pre-wet composition 13 is applied directly onto the patterned substrate 11. The pre-wet composition is preferably formed by a spin coating method. In this embodiment, of the above-mentioned pre-wet compositions, it is more preferable to use PGME or EL. In this specification, unless otherwise specified, in the description of the method, "directly on" means without an intermediate layer, and "on" and "above" include both a state with an intermediate layer and a state without an intermediate layer. In this embodiment, the surface of the patterned substrate 11 may be subjected to a hydrophilization treatment before the application of the prewet composition. For example, the hydrophilization treatment may be performed by bringing the surface of the patterned substrate 11 into contact with a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH). This allows hydrophilic groups (OH groups) to be terminated on the surface of the patterned substrate 11, thereby increasing the wettability of the surface.

[0040] Next, as shown in FIG. 1C , an underlayer film composition is applied to the patterned substrate 11 to form an underlayer film 15. At this time, immediately before applying the underlayer film composition, the prewet composition 13 may remain on the entire surface of the patterned substrate 11, or may remain partially. Preferably, the prewet composition 13 does not form a layer or film. The underlayer film composition is preferably applied by dropping it onto the center of the substrate. At this time, it is preferable that the substrate is rotating. Without being bound by theory, it is believed that the prewet composition 13 present on the patterned substrate 11 helps the underlayer film composition to spread wetly with good coverage and / or conformality when applied. Preferably, the prewet composition 13 present on the patterned substrate 11 is removed from the substrate by being pushed out by the underlayer film composition when applying the underlayer film composition. The underlayer film composition includes an aminoplast and a polyfunctional alcohol. The aminoplast may be glycoluril, melamine, or benzoguanamine. [ka] [ka] [ka] The polyfunctional alcohol may be Polymer A or Polymer C. [ka] [ka]

[0041] In this embodiment, it is desirable to apply the underlayer film composition before volatilization of the prewet composition 13. Without being bound by theory, it is thought that the underlayer film composition applied to the substrate spreads while mixing and dissolving with the prewet composition 13, which makes it easier for the underlayer film composition to wet and spread over the substrate surface.

[0042] Next, the underlayer film 15 is heat-treated. The heating temperature is 80 to 280°C, preferably 100 to 240°C, and more preferably 120 to 200°C. The heating time may be 30 to 180 seconds. This hardens the underlayer film 15. The heat treatment may be a multi-stage heat treatment using a plurality of temperatures. The film thickness of the underlayer film 15 after heating is 1 nm to 500 nm, preferably 2 nm to 200 nm, more preferably 4 nm to 100 nm, and even more preferably 5 nm to 50 nm. In this example, the film thickness of the underlayer film 15 is 22 nm. The formed underlayer film 15 has an optical constant (n) value measured with light having a wavelength of 248 nm of 1.60 to 1.90, preferably 1.65 to 1.85, and more preferably 1.70 to 1.80. The (k) value is 0.05 to 0.40, preferably 0.10 to 0.35, and more preferably 0.15 to 0.30. This allows the underlayer film 15 to be used as a BARC. The BARC can improve the cross-sectional shape and exposure margin. When the underlayer film 15 is used as an etching mask, it is preferable that the underlayer film 15 has etching resistance.

[0043] In this embodiment, the underlayer film 15 is formed conformally on the patterned substrate 11. FIG. 2 is a schematic diagram of the underlayer film formed on the patterned substrate 11. As shown in FIG. 2, in this embodiment, the underlayer film 15 does not necessarily need to be present on a portion of the patterned substrate 11 extending from the upper end to the inner side and on the side (wall) portions of the pattern. FIG. 3 is a schematic diagram showing coverage and conformality. In FIG. 3, for example, the distance from the upper corner (upper end) 11ae of the patterned wall 11a to the end 15e of the underlayer film 15 at the top of the patterned wall 11a is 0 to 70 nm, preferably 0 to 50 nm, more preferably 0 to 40 nm, even more preferably 0 to 30 nm, and even more preferably 0 to 20 nm. The ratio (X / Y) of the film thickness (X) of the underlayer film 15 at the top of the pattern wall to the film thickness (Y) of the underlayer film at the bottom of the groove between the pattern walls is 0.20 to 0.99, preferably 0.25 to 0.99, more preferably 0.40 to 0.99, and even more preferably 0.50 to 0.99. In this specification, the coverage and conformality are preferably confirmed as described in the Examples, and more specifically, they are preferably confirmed using a substrate having a pattern with a pattern width of 500 nm / space width of 500 nm and a height of 100 nm.

[0044] 1D, a resist film 17 is formed by coating on the pattern substrate 11. The thickness of the resist film 17 is desirably 50 to 500 nm, preferably 80 to 400 nm, and more preferably 100 to 300 nm. The resist film 17 may be heat-treated.

[0045] 1E, the resist film 17 is processed to form a resist pattern 19. The resist pattern 19 can be formed by combining known methods (for example, photolithography).

[0046] When etching the patterned substrate 11, it is preferable to use the resist pattern 19 as a mask to etch the underlying film 15 and the patterned substrate 11 at once. Alternatively, the underlying film 15 may be etched using the resist pattern 19 as a mask, and then the patterned substrate 11 (more specifically, the upper portions of the pattern walls of the patterned substrate and / or the grooves between the patterned walls; a more specific and even more preferred example is the upper portions of the patterned walls) may be etched using the underlying film 15 as a mask. The etching may be wet etching or dry etching (more preferably, dry etching). This allows for the production of a processed substrate in which a new pattern is formed on the patterned substrate 11.

[0047] The processed substrate described above can be further processed to produce a device. Examples of the device include a semiconductor element, a liquid crystal display element, an organic EL display element, a plasma display element, and a solar cell element. The device is preferably a semiconductor. These can be processed using known methods. After the device is formed, the substrate can be cut into chips, connected to a lead frame, and packaged with resin, as needed. An example of this packaged product is a semiconductor.

[0048] As described above, by using the pre-wet composition according to one embodiment of this invention, the wettability of the patterned substrate 11 is improved, and therefore the coverage and conformality of the underlayer film 15 to the patterned substrate 11 can be improved.

[0049] (Variation) Within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications and alterations, and it is understood that these modifications and alterations also fall within the scope of the present invention. For example, to the above-described embodiments, a person skilled in the art may appropriately add or delete components, combine or change the design of the embodiments, or add or omit processing or change conditions, and these modifications and alterations are also included within the scope of the present invention as long as they maintain the gist of the present invention.

[0050] In one embodiment of the present invention, an example in which BARC is used as the underlayer film 15 has been described, but the present invention is not limited thereto. The underlayer film 15 may be a coated carbon film (also referred to as a coated C film, a spin-on carbon film, or an SOC film). The coated carbon film layer 12 may be formed by coating using a known method such as spin coating, followed by pre-baking. [Example]

[0051] The patterned substrate prewet composition according to one embodiment of the present invention will be described in more detail below with reference to examples. However, the patterned substrate prewet composition according to one embodiment of the present invention is not limited to the following examples.

[0052] [Preparation example of underlayer film composition 1] 3 g of poly(4-vinylphenol) (Polymer A, manufactured by Merck) and 1 g of tetramethoxymethylglycoluril (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter referred to as TCI) are dissolved in 66.95 g of PGMEA / 29 g of PGME solvent to obtain a solution. [ka] 0.05 g of dodecylbenzenesulfonic acid / triethylamine (molar ratio 1:1) is added to the polymer solution. The mixture is then filtered through a microfilter with a 0.2 μm pore size to obtain Solution 1. 40 parts by weight of PGMEA and 25 parts by weight of PGME are added to 35 parts by weight of Solution 1 and mixed. The mixture is filtered through a microfilter with a 0.2 μm pore size to obtain Underlayer Film Composition 1.

[0053] [Synthesis Example B of Polymer B] 600 grams of tetramethoxymethyl glycoluril (TCI) and 96 grams of styrene glycol (TCI) were added to 1200 grams of PGMEA and placed in a 2 L jacketed flask equipped with a thermometer, mechanical stirrer, and cold water condenser. The flask was heated to 85°C. The flask was removed, and a catalytic amount of para-toluenesulfonic acid monohydrate was added from the top of the flask. The reaction was then maintained at 85°C for 5 hours. The reaction solution was then returned to room temperature and filtered to obtain a filtrate. The filtrate was slowly poured into ion-exchanged water with stirring to precipitate a polymer. The polymer was filtered, thoroughly washed with water, and dried in a vacuum oven. 250 grams of Polymer B were obtained. The resulting Polymer B was confirmed to have a weight-average molecular weight of approximately 17,345 and a polydispersity of 2.7. [ka]

[0054] [Synthesis Example C of Polymer C] 20 g of butanetetracarboxylic dianhydride (Fujifilm Wako Pure Chemical Industries, Ltd.), 20 g of (+)-dimethyl L-tartrate (TCI), and 1.0 g of benzyltributylammonium chloride (TCI) were added to 70 g of PGMEA to obtain a solution. The solution was placed in a flask equipped with a condenser, temperature controller, and mechanical stirrer. The solution in the flask was stirred under a nitrogen atmosphere and heated to 110°C. After 1-2 hours, a clear solution was obtained. The temperature was raised to 110°C and maintained for 4 hours. The solution was cooled to 60°C. 40 g of PGMEA, 60 g of acetonitrile, 68 g of propylene oxide (TCI), and 30 g of tris(2,3-epoxypropyl)isocyanurate (Merck) were added to the above solution and mixed. The reaction was continued at 52°C for 40 hours. The reaction solution was then cooled to room temperature. The reaction solution is slowly poured into a large amount of water in a high-speed blender. The precipitated polymer is collected and washed thoroughly with water. The polymer is dried in a vacuum oven. 40 grams of Polymer C are obtained. Polymer C has a weight average molecular weight of about 32,000. [ka] [Preparation Example 2 of Underlayer Film Composition 2] 68.95 g of PGMEA and 27 g of PGME are mixed to obtain a mixed solution. 3 g of Polymer B and 1 g of Polymer C were added to the mixture to obtain a solution. 0.05 g of dodecylbenzenesulfonic acid (TCI) / triethylamine (molar ratio 1:1) (TCI) was added to the solution and dissolved. This was filtered through a microfilter with a 0.2 μm pore size to obtain Solution 2. 40 parts by weight of PGMEA and 25 parts by weight of PGME were added to 35 parts by weight of Solution 2 and mixed. This mixture was filtered through a microfilter with a 0.2 μm pore size to obtain Underlayer Film Composition 2.

[0055] [Examples of preparing wafers with underlayer films formed thereon. Examples 1 to 9] A 4-inch silicon wafer with a SiO2 pattern of 500 nm pattern width / 500 nm space width (1:1 line and space) and 100 nm height is prepared. The wafer is immersed in a 2.38% TMAH aqueous solution for 10 seconds, then washed with pure water and dried to make the pattern surface hydrophilic.

[0056] The hydrophilized wafer is placed on a spin coater (MS-B200, manufactured by Mikasa Co., Ltd.). The wafer is programmed to rotate at 500 rpm for 15 seconds, followed by 1500 rpm for 20 seconds. 2 mL of each pre-wet composition listed in Table 1 below is dispensed onto the center of the wafer, and the spin coater is started. Five seconds later, 2 mL of each underlayer film composition listed in the table is dispensed onto the center of the wafer (while rotating) in a state where the pre-wet composition has been sufficiently applied to the patterned wafer. The underlayer film composition is applied onto the wafer by rotating the wafer according to the programmed settings.

[0057] The wafer is heated on a hot plate at 110°C for 60 seconds, and then further heated on a hot plate at 200°C for 60 seconds, thereby obtaining a wafer on which a cured underlayer film has been formed.

[0058] [Example of preparation of wafer with underlayer film formed. Comparative Example 1] A wafer having a cured underlayer film formed thereon was obtained by a method similar to that of Examples 1 to 9, except that no pre-wet composition was used and the program setting conditions were changed as follows.

[0059] The hydrophilized wafer was placed on a spin coater (MS-B200). The wafer was programmed to spin at 500 rpm for 5 seconds, followed by 1500 rpm for 20 seconds. No pre-wet composition was added. 2 mL of the underlayer film composition listed in Table 1 was added, and the spin coater was started.

[0060] [SEM section formation and observation example] An SEM section of the wafer on which the underlayer film was formed was observed at a magnification of 200,000 times using an electron microscope SU8230 (manufactured by Hitachi High-Technologies Corporation).

[0061] [Conformality evaluation] Conformality is evaluated as follows based on the formation and observation of SEM sections. As shown in the schematic diagram in Figure 3, the thickness X (nm) of the underlayer film is measured at a point 250 nm from the top corner of the pattern wall. Also, the thickness Y (nm) of the BARC is measured at a point 250 nm from the bottom corner of the groove between the pattern walls. Based on (X / Y), conformality is evaluated using the following criteria. The evaluation results are listed in Table 1. [Table 1]

[0062] From Table 1, it can be seen that the larger the X / Y value, the thicker the underlying film formed on top of the pattern, meaning higher conformality (classified as "A"). The evaluation criteria are as follows: A: (X / Y)≧0.5 Sufficient conformality. B: 0.20≦(X / Y)<0.5 Has a certain degree of conformality. C: (X / Y)<0.20 Conformity is insufficient.

[0063] [Evaluation of coverage] Coverage was evaluated as follows based on the formation and observation of SEM slices. When the upper corner (top end) of the pattern wall was not covered with the underlayer film, the distance from the corner (top end) of the uncovered area to the end of the underlayer film was taken as Z (nm), and the length of Z was measured. The evaluation criteria were as follows. The evaluation results are shown in Table 2. Figure 4 is an SEM observation photograph of an example of a pattern substrate on which an underlayer film was formed, which received an A rating in the evaluation of coverage. Figure 5 is an SEM observation photograph of an example of a pattern substrate on which an underlayer film was formed, which received a C rating in the evaluation of coverage. [Table 2] For A: Z = 0 pattern, the corners at the upper part of the pattern wall are completely covered by the lower layer film. For B: 0 < Z ≤ 50 pattern, the corners at the upper part of the pattern wall are not completely covered by the lower layer film and are partially exposed. It has a certain degree of coverage. For C: Z > 50 pattern, the corners at the upper part of the pattern wall are not covered by the lower layer film and are largely exposed. The coverage is insufficient (Figure 5).

[0064] As can be seen from Table 2, in terms of coverage, it can be seen that Examples 1 to 9 are superior to Comparative Example 1 as the pattern substrate pre-wet composition.

Explanation of Signs

[0065] 11: Pattern substrate 13: Pre-wet composition 15: Lower layer film 17: Resist film 19: Resist pattern

Claims

1. The vapor pressure at 20°C is 0.05 to 40 mmHg, The surface tension at 20°C is 15 to 60 dyn / cm. Patterned substrate prewet composition.

2. The viscosity of the pattern substrate pre-wetting composition at 20°C is 0.5 to 20.0 cP; The patterned substrate prewet composition of claim 1 .

3. The patterned substrate pre-wetting composition contains an organic solvent (A), Optionally, the organic solvent (A) is one organic solvent or a mixture of two or more organic solvents. The patterned substrate prewet composition of claim 1 .

4. the organic solvent contained in the organic solvent (A) is an alcohol solvent, an ether solvent, an ester solvent, a ketone solvent, a hydrocarbon solvent, or any combination thereof; The patterned substrate prewet composition of claim 3 .

5. The organic solvent (A) contains at least one selected from the group consisting of propylene glycol monomethyl ether, ethyl lactate, n-pentanol, and n-hexanol. The patterned substrate prewet composition of claim 3 .

6. Further comprising an additive (B), Optionally, the additive (B) is selected from a surfactant, an acid, a base, a substrate adhesion promoter, an antifoaming agent, or any combination thereof; Optionally, the content of the additive (B) is 0 to 3 mass% compared to the entire pattern substrate pre-wet composition; The patterned substrate prewet composition of claim 1 .

7. the patterned substrate includes two adjacent patterns and a space between the at least two patterns; The ratio of the pattern width to the space width is 1 / 100 to 1 / 100. The patterned substrate prewet composition of claim 1 .

8. The vapor pressure at 20°C is 0.05 to 40 mmHg, A pre-wet composition having a surface tension of 15 to 60 dyn / cm at 20°C, For use in coating directly onto patterned substrates.

9. Prepare a patterned substrate, Applying a patterned substrate pre-wet composition directly onto the patterned substrate; applying an underlayer film composition onto the patterned substrate to form an underlayer film; Optionally, heating the underlayer film; forming a resist film directly on the underlayer film; forming a resist pattern by processing the resist film; A method for producing a resist pattern.

10. The underlayer film composition comprises an aminoplast and a polyfunctional alcohol. The method for producing a resist pattern according to claim 9 .

11. The aminoplast includes glycoluril, melamine, or benzoguanamine. The method for producing a resist pattern according to claim 10 . 【Chemistry 1】 【Chemistry 2】 【Transformation 3】

12. When preparing the patterned substrate, the surface of the patterned substrate is subjected to a hydrophilic treatment. The method for producing a resist pattern according to claim 9 .

13. Heating the underlayer film at 80 to 280°C for 30 to 180 seconds, Optionally, the underlayer film is heated at 120 to 200°C for 30 to 180 seconds; The method for producing a resist pattern according to claim 9 .

14. the pattern substrate includes two adjacent patterns and a space between the two patterns; The ratio of the pattern width to the space width is 1 / 100 to 1 / 100, a ratio (X / Y) of a film thickness (X) of the underlayer film on the pattern to a film thickness (Y) of the underlayer film on the space is 0.20 to 0.99; The method for producing a resist pattern according to claim 9 .

15. the distance from the top edge of the pattern to the edge of the underlayer film on the pattern is 0 to 70 nm; A method for producing a resist pattern according to claim 14.

16. the underlayer film has optical constants, as measured with light having a wavelength of 248 nm, of an (n) value of 1.60 to 1.90 and / or a (k) value of 0.05 to 0.40; A method for producing a resist pattern according to claim 9.

17. Producing a resist pattern by the method according to any one of claims 9 to 16; (6) Processing using the resist pattern as a mask, A method for manufacturing a processed substrate.

18. The target to be processed using the resist pattern as a mask is a patterned substrate or an underlying film, Optionally, when the target to be processed is a patterned substrate, the target portion is an upper portion of a patterned wall of the patterned substrate and / or a groove between the patterned walls; The method for manufacturing a processed substrate according to claim 17.

19. The method for manufacturing a processed substrate according to claim 18, How the device is manufactured.

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