Method for forming organic film and method for manufacturing substrate for semiconductor device

Abstract

This invention provides a method for forming an organic film, which, in the manufacturing process of semiconductor devices and the like, can fill in the uneven patterns on a substrate, thereby achieving a high degree of planarization of the substrate at low cost. The method for forming an organic film is characterized by comprising: a step of spin-coating an organic film forming composition onto the substrate to form a coating film; a step of spin-coating a coating solvent capable of dissolving the coating film with a standard boiling point of 160°C or higher and below 500°C onto the coating film; and a step of forming an organic film by subjecting the coating film to an insoluble treatment relative to the coating solvent.

Description

[Technical Field]

[0001] The present invention relates to a method for forming a flat organic film that can be used in the microfabrication process of semiconductor devices, and a method for manufacturing a substrate for semiconductor devices using the organic film forming method. [Previous Technology]

[0002] The miniaturization of pattern sizes resulting from the shortening of light source wavelengths in lithography technology has driven the improvement of processing performance in semiconductor devices. However, the rate of wavelength shortening after ArF light sources has slowed down, necessitating performance improvements to replace miniaturization. Therefore, methods have been developed to improve the performance of semiconductor devices by forming their structures in three dimensions and arranging transistors at higher densities. In the substrate of a semiconductor device with such a three-dimensional structure, the circuit pattern is formed in a deeper and finer structure compared to existing substrates. Therefore, existing lithography techniques, which are best suited for forming planar structures, do not offer practical process tolerance. Therefore, it is necessary to form a flat surface by applying a material capable of planarizing the substrate with the three-dimensional structure, and then patterning on that flat surface using lithography technology to ensure process tolerance.

[0003] As a method for forming such a flat surface, many methods for forming a planarization film using spin-coated organic films are known (Patent Documents 1-5). However, organic films formed using such materials cannot be adapted to all patterns on substrates used in semiconductor device manufacturing. Furthermore, solutions have been proposed that add liquid additives such as polyether polyols and polyacetals (Patent Documents 6-7). However, since such additives typically have poor dry etching resistance, if they remain in the coating film, the dry etching resistance during substrate processing may be insufficient. Therefore, the dry etching resistance of the organic film used for substrate processing may also be insufficient. In addition, as a planarization method, a method has been practically applied in which planarization is performed using chemical mechanical polishing (CMP) technology after the unevenness on the substrate is filled (Patent Document 8). However, CMP is a high-cost process. Under these circumstances, a method is sought to use organic films to achieve a high degree of planarization of substrates used in semiconductor device manufacturing at low cost. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2005-292528 [Patent Document 2] Japanese Patent Application Publication No. 2008-65081 [Patent Document 3] Japanese Patent Application Publication No. 2008-242492 [Patent Document 4] Japanese Patent Application Publication No. 2014-24831 [Patent Document 5] Japanese Patent Application Publication No. 2014-219559 [Patent Document 6] International Publication No. 2008 / 026468 [Patent Document 7] Japanese Patent Application Publication No. 2013-253227 [Patent Document 8] Japanese Patent Application Publication No. 2004-335873 [Summary of the Invention]

[0005] [Problem to be Solved by the Invention] The present invention has been made in view of the above-mentioned situation, and its object is to provide a method for forming an organic film that can fill in the uneven patterns on a substrate during the manufacturing process of semiconductor devices, etc., thereby achieving a high degree of planarization of the substrate at low cost. [Means for Solving the Problem]

[0006] To achieve the above objective, the present invention provides an organic film forming method, which is a method for forming an organic film on a substrate having a pattern of concavity and convexity, characterized by comprising the following steps: a step of spin-coating an organic film forming composition onto the aforementioned substrate to form a coating film; a step of spin-coating a coating solvent capable of dissolving the coating film with a standard boiling point of 160°C or higher and less than 500°C onto the coating film; and a step of forming an organic film by performing an insoluble treatment on the coating film relative to the coating solvent.

[0007] If this method is used, then in the manufacturing process of semiconductor devices, an organic film can be formed to fill the uneven pattern on the substrate and achieve a high degree of planarization of the substrate at low cost.

[0008] In addition, as the above-mentioned insoluble treatment, it is preferable to use any one or a combination of heat treatment at 100°C or above and 600°C, ultraviolet irradiation treatment with a wavelength of 400nm or below, electron beam irradiation treatment and plasma irradiation treatment.

[0009] By using such a method for insoluble treatment, an organic film that maintains a flat state can be formed.

[0010] In addition, alcohols, esters, ketones, carbonates, ethers or combinations thereof are preferred as the coating solvents described above.

[0011] By using such a coating solvent, an organic film that can highly planarize the substrate can be formed.

[0012] As the above-mentioned coating solvent, it is preferable to use an aromatic compound having benzyl or benzoyl groups.

[0013] If such an aromatic compound is used, the solubility and wettability of the organic membrane become suitable, and the organic membrane can be planarized to a greater extent.

[0014] Furthermore, as the aforementioned composition for forming organic films, it is preferable to use a composition containing a resin comprising one or more aromatic rings.

[0015] In the method for forming the organic film of the present invention, from the viewpoints of etching resistance, optical properties and heat resistance, an organic film forming composition comprising a resin containing an aromatic ring can be suitably used.

[0016] Furthermore, the present invention provides a method for manufacturing a substrate for a semiconductor device, which involves forming an organic film on a substrate having a raised or recessed pattern using the method described above; forming a silicon-containing resist intermediate film using a silicon-containing resist intermediate film forming composition on the organic film; forming a resist upper layer film using a photoresist composition on the silicon-containing resist intermediate film; forming a circuit pattern on the resist upper layer film; using the resist upper layer film with the pattern formed thereon as a mask; transferring the pattern to the silicon-containing resist intermediate film using dry etching; using the silicon-containing resist intermediate film with the transferred pattern as a mask; transferring the pattern to the organic film using dry etching; and then using the organic film with the transferred pattern as a mask; transferring the pattern to the substrate using dry etching.

[0017] In addition, the present invention provides a method for manufacturing a substrate for a semiconductor device, which involves forming an organic film on a substrate having a raised or recessed pattern using the above-described method, forming a silicon-containing resist intermediate film on the organic film using a silicon-containing resist intermediate film forming composition, forming an organic anti-reflective film on the silicon-containing resist intermediate film, forming a resist upper film on the organic anti-reflective film using a photoresist composition to form a resist upper film, thereby forming four resist films, forming a circuit pattern on the aforementioned resist upper film, using the resist upper film with the pattern formed thereon as a mask, transferring the pattern to the aforementioned organic anti-reflective film and the aforementioned silicon-containing resist intermediate film by dry etching, using the organic anti-reflective film and the silicon-containing resist intermediate film with the transferred pattern as a mask, transferring the pattern to the aforementioned organic film by dry etching, and then using the organic film with the transferred pattern as a mask, transferring the pattern to the aforementioned substrate by dry etching.

[0018] In addition, the present invention provides a method for manufacturing a substrate for a semiconductor device, which involves forming an organic film on a substrate having a raised or recessed pattern using the above method, forming an inorganic hard mask selected from silicon oxide film, silicon nitride film, silicon oxynitride film, amorphous silicon film, and titanium nitride film on the organic film, forming a photoresist upper layer film on the inorganic hard mask using a photoresist composition, forming a circuit pattern on the photoresist upper layer film, using the photoresist upper layer film with the pattern formed thereon as a mask, transferring the pattern to the inorganic hard mask by dry etching, using the inorganic hard mask with the transferred pattern as a mask, transferring the pattern to an organic film by dry etching, and then using the organic film with the transferred pattern as a mask, transferring the pattern to the substrate by dry etching.

[0019] Furthermore, the present invention provides a method for manufacturing a substrate for a semiconductor device, which involves forming an organic film on a substrate having a raised or recessed pattern using the above-described method, forming an inorganic hard mask selected from silicon oxide film, silicon nitride film, silicon oxynitride film, amorphous silicon film, and titanium nitride film on the organic film, forming a multilayer resist film or organic antireflective film composed of an organic film and a silicon-containing resist intermediate film on the inorganic hard mask, and using a photoresist to form a shape on the multilayer resist film or organic antireflective film. A resist upper layer film is formed, and a circuit pattern is formed on the resist upper layer film. The resist upper layer film with the pattern is used as a mask. The pattern is transferred to the aforementioned inorganic hard mask by dry etching through the pattern transfer of the aforementioned multilayer resist film or the aforementioned organic antireflective film. The inorganic hard mask with the transferred pattern is used as a mask, and the pattern is transferred to the organic film formed on the aforementioned substrate by dry etching. Then, the organic film with the transferred pattern is used as a mask, and the pattern is transferred to the aforementioned substrate by dry etching.

[0020] As described above, since the organic film formed using the method of the present invention has excellent flatness characteristics, by combining this organic film with various film materials in multilayer resist technologies such as two-layer resist technology, three-layer resist technology using a silicon-containing resist intermediate film, or four-layer resist technology using a silicon-containing resist intermediate film and an organic anti-reflective film, the pattern of the upper photoresist (resist upper film) can be transferred to the substrate with high precision, thereby forming a pattern on the substrate. That is, if it is the semiconductor device substrate manufacturing method of the present invention, a high-precision semiconductor device substrate can be manufactured.

[0021] In this case, it is preferable to use chemical vapor deposition (CVD) or atomic layer deposition (ALD) to form the above-mentioned inorganic hard mask.

[0022] In the method for manufacturing a substrate for a semiconductor device according to the present invention, an inorganic hard mask may be formed, for example, by such a method.

[0023] In addition, in the formation of the circuit pattern, it is preferred to form the circuit pattern by any one or a combination of high-energy rays with wavelengths of 10 nm or more and 300 nm or less, direct drawing based on electron beams, and nanoimprinting.

[0024] In addition, in the formation of the above-mentioned circuit pattern, it is preferable to develop the circuit pattern using alkaline development or organic solvent development.

[0025] In the method for manufacturing a semiconductor device substrate of the present invention, it is preferable to use means for forming and developing such a circuit pattern. [Effects of the Invention]

[0026] As explained above, according to the present invention, an organic film can be formed to fill the uneven pattern on the substrate, thereby enabling the substrate to be highly planarized. Furthermore, since the substrate can be highly planarized without using CMP, a high-cost technology, substrate planarization can be performed at a low cost. Moreover, the organic film formed using the method of the present invention has excellent planarization characteristics, making it extremely useful in semiconductor device manufacturing. By combining this organic film with various film materials in multilayer resist technologies, such as two-layer resist technology, three-layer resist technology using a silicon-containing resist interlayer film, or four-layer resist technology using a silicon-containing resist interlayer film and an organic antireflective film, the pattern of the upper photoresist (resist upper film) can be transferred to the substrate with high precision, thus forming a pattern on the substrate. In other words, if the semiconductor device substrate manufacturing method of the present invention is followed, a high-precision semiconductor device substrate can be manufactured.

Implementation Method

[0028] As described above, in the manufacturing process of semiconductor devices, there is a need to develop a method for forming an organic film that fills the uneven pattern on a substrate and can achieve a high degree of planarization of the substrate at low cost.

[0029] Conventionally, a method for planarizing a substrate with a raised or recessed pattern, such as a substrate on which a semiconductor circuit is formed, involves spin-coating an organic film forming composition onto the substrate, followed by baking, thereby filling the raised or recessed pattern on the substrate surface with the organic film to form a flat surface. However, while this method can fill in minute irregularities on the surface, it is difficult to uniformly form a flat surface across the entire substrate surface, between high-density and low-density areas of the pattern that must be filled. Typically, the coated composition forms a raised or recessed coating film that follows the raised or recessed pattern formed on the substrate. Typically, in the process of forming a semiconductor circuit, such a coating film is subjected to an insoluble treatment before proceeding to the step of forming the next film. The inventors conducted extensive research on substrate planarization and discovered that by spin-coating a coating solution with a standard boiling point of 160°C or higher and below 500°C onto the aforementioned coating film after coating the organic film formation composition and before the aforementioned insoluble treatment, and allowing the coating film to flow, an extremely flat organic film can be formed, thus completing the present invention. It should be noted that in the present invention, "standard boiling point" refers to the boiling point at 1 atmosphere (1013.25 hPa). Hereinafter, it will sometimes be simply referred to as "boiling point".

[0030] That is, the present invention is an organic film forming method, which is a method for forming an organic film on a substrate having a raised or recessed pattern, characterized by comprising the following steps: a step of spin-coating an organic film forming composition onto the aforementioned substrate to form a coating film; a step of spin-coating a coating solvent capable of dissolving the coating film with a standard boiling point of 160°C or higher and less than 500°C onto the coating film; and a step of forming an organic film by performing an insoluble treatment on the coating film relative to the coating solvent.

[0031] Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto.

[0032] The present invention relates to a method for forming an extremely flat organic film that can be used in microfabrication steps of semiconductor devices, and a method for manufacturing a semiconductor device substrate using the organic film forming method. The method for forming the organic film of the present invention and the method for manufacturing a semiconductor device substrate using the organic film forming method will be described below.

[0033] <Method for Forming an Organic Film> This invention relates to a method for forming an organic film on a substrate having an uneven pattern, characterized by comprising the following steps: a step of spin-coating an organic film forming composition onto the aforementioned substrate to form a coating film (coating film forming step); a step of spin-coating a coating solvent capable of dissolving the coating film with a standard boiling point of 160°C or higher and less than 500°C onto the coating film (coating solvent coating step); and a step of forming an organic film by subjecting the coating film to an insoluble treatment relative to the coating solvent (organic film forming step). In this invention, the coating solvent refers to an organic solution coated on the coating film formed on the substrate, which is an organic solution capable of dissolving the coating film and having a standard boiling point of 160°C or higher and less than 500°C. The coating solvent may be different from or the same as the organic solvent contained in the coating film (derived from the organic solvent contained in the organic film forming composition), preferably having a standard boiling point higher than that of the organic solvent contained in the coating film.

[0034] The standard boiling point can be determined from the boiling point under reduced pressure (below 1 atmosphere) using the values ​​recorded in Chemical Handbook (Basic Edition) (6th revised edition, edited by the Chemical Society of Japan, Maruzen Publishing, January 2021) and Solvent Handbook (edited by Teruzo Asahara, Kodansha, 1976), using the method described in the literature (Science of Petroleum, Vol. II, p1281, (1938)). Furthermore, in spin coating, there are static dispense methods where the solvent (fluid) is dripped onto the substrate while it is stationary, and the substrate is rotated after the solvent is dripped to coat it; and dynamic dispense methods where the solvent is dripped while the substrate is rotated to coat it. In this invention, either static dispense or dynamic dispense can be used.

[0035] Hereinafter, the present invention will be described with reference to the drawings. FIG1 is a flowchart of an example of forming an organic film on a substrate having a groove pattern using the organic film forming method of the present invention. In the method of FIG1, firstly, an organic film forming composition is spin-coated onto a substrate 1 to form a coating film 2. At this time, under the influence of the uneven pattern on the substrate 1, the coating film 2 with unevenness is formed in a form that follows the shape of the substrate (FIG. 1(A)). The coating film 2 is then treated with a coating solvent 3 having a standard boiling point of 160°C or higher and less than 500°C. When the above-mentioned coating solvent 3 is applied to the uncured coating film 2, the coating film 2 (mainly the resin in the coating film 2) flows (FIG. 1(B)). As a result, the unevenness is eliminated, and a flat coating film 2 is formed (FIG. 1(C)). Finally, the flat coating film 2 can be insoluble by heat, light, plasma, or any combination thereof to form a flat organic film 4 (FIG. 1(D)). Then, a coating film can be formed by spin-coating a coating film forming composition, such as a silicon-containing intermediate film forming composition described later, onto the insoluble organic film 4. It should be noted that, in the method of FIG1, after the coating film 2 is formed, the organic solvent contained in the coating film 2 can be removed by heat, light, plasma, or any combination thereof within the range where the coating film 2 is not completely hardened.

[0036] FIG2 is a flowchart of an example of forming an organic film over a wide area with fine patterns on a substrate having a line pattern (line and spacing pattern) using the organic film formation method of the present invention. First, in the method of FIG2, an organic film forming composition is first spin-coated onto a substrate 1 to form a coating film 2. At this time, when the pattern pitch is large, as shown in FIG1, due to the influence of the uneven pattern on the substrate, the coating film 2 with unevenness is formed in a form that follows the shape of the substrate. However, in fine patterns, such as patterns with a half pitch finer than 200 nm, it does not follow each pattern, but forms a coating film 2 with the center of the pattern being concave (the patterned part is generally a gently concave shape) (FIG. 2(A)). A coating solvent 3 with a standard boiling point of 160°C or higher and less than 500°C is spin-coated onto the coating film 2. When the above-mentioned coating solvent 3 is coated onto the uncured coating film 2, the coating film 2 (mainly the resin in the coating film 2) flows (FIG. 2(B)). As a result, the unevenness is eliminated, forming a flat coating film 2 (Fig. 2(C)). Finally, the flat coating film 2 is insoluble by treatment with heat, light, plasma, or any combination thereof, thereby forming a flat organic film 4 (Fig. 2(D)). Then, a coating film is formed on the insoluble organic film 4 by spin-coating, for example, a coating film forming composition such as a silicon-containing inhibitor intermediate film forming composition described later. It should be noted that in the method of FIG. 2, after the coating film 2 is formed, the organic solvent contained in the coating film 2 can be removed by treatment with heat, light, plasma, or any combination thereof within the range where the coating film 2 is not completely hardened.

[0037] Hereinafter, the steps of the method for forming the organic film of the present invention will be described in more detail.

[0038] [Coating Film Formation Step] In the organic film formation method of the present invention, an organic film forming composition is first spin-coated onto a substrate having a raised or recessed pattern to form a coating film. The substrate having the raised or recessed pattern is not particularly limited; for example, a substrate having a groove pattern, a spacing pattern, or a line pattern can be used. Furthermore, the organic film forming composition used in the present invention is not particularly limited, but it is preferable to use an organic film forming composition containing one or more aromatic rings. It should be noted that spin-coating is not particularly limited, and can be performed using a spin coater or other known methods.

[0039] In this invention, after the coating film is formed, the organic solvent contained in the coating film can be removed by heat, light, plasma or any combination thereof within the range where the coating film is not completely hardened.

[0040] The heat, light, or plasma irradiation method can use the same method as the insoluble treatment method described below. From the viewpoint of ease of treatment, heat treatment is preferred, more preferably heat treatment at 50°C or higher and 450°C or lower, further preferably heat treatment at 80°C or higher and 400°C or lower, and particularly preferably heat treatment at 100°C or higher and 350°C or lower.

[0041] The organic film-forming resin that can be used in the composition for forming organic films used in the present invention is not particularly limited as long as it satisfies the film-forming and curing properties of spin coating. From the viewpoints of etching resistance, optical properties, and heat resistance, it is more preferably a compound containing an aromatic skeleton.

[0042] Examples of aromatic skeletons include: benzene, naphthalene, anthracene, pyrene, indene, fumonisin, furan, pyrrole, thiophene, phosphole, pyrazole, phosphonazole, isophosphonazole, thiazole, pyridine, pyrazine, pyrimidine, pyridoxine, triazole, carbazole, etc. Among these, benzene, naphthalene, and fumonisin are particularly preferred.

[0043] As an organic film-forming resin suitable for the present invention, examples include resins containing the following structures as described in Japanese Patent Application Publication No. 2012-1687 and Japanese Patent Application Publication No. 2012-77295. [Chemical 1] In formula (1), the ring structures Ar1 and Ar2 represent benzene rings or naphthalene rings. X represents a single bond or an alkyl group having 1 to 20 carbon atoms. m represents 0 or 1. n represents any natural number that makes the molecular weight 100,000 or less. It should be noted that the symbols in the formula are only applicable to this formula.

[0044] [Chemical 2] In formula (2), the ring structures Ar1 and Ar2 represent benzene rings or naphthalene rings. n represents any natural number with a converted weight-average molecular weight of polystyrene (elution buffer: THF) of less than 100,000 based on gel permeation chromatography. It should be noted that the symbols in the formula are only applicable in this formula.

[0045] As an organic film-forming resin suitable for the present invention, examples may further include resins containing the following structure as described in Japanese Patent Application Publication Nos. 2004-264710, 2005-043471, 2005-250434, 2007-293294, and 2008-65303. [Chemical 3] In formulas (3) and (4), R1 and R2 represent hydrogen atoms or alkyl or aryl groups having 1 to 3 carbon atoms, R3 represents alkyl, vinyl, allyl, or substituted aryl groups having 1 to 3 carbon atoms, n represents 0 or 1, and m represents 0, 1, or 2. It should be noted that the symbols in the formulas are only applicable in this formula.

[0046] [Chemical Engineering 4] In formula (5), R1 is a monovalent atom or base other than hydrogen, and n is an integer from 0 to 4. When n is 2 to 4, multiple R1s can be the same or different. R2 and R3 are independently monovalent atoms or bases. X is a divalent base. It should be noted that the symbols in the formula are only applicable in this formula.

[0047] [Chemical 5] In formula (6), R1 is a hydrogen atom or a methyl group. R2 is any one of a single bond, a straight-chain, branched, cyclic alkyl group with 1 to 20 carbon atoms, or an aryl group with 6 to 10 carbon atoms, and may be any one of an ether, ester, lactone, or acetylamine. R3 and R4 are each a hydrogen atom or an epoxypropyl group. X represents any one of a hydrocarbon containing an indene skeleton, a cyclic olefin with 3 to 10 carbon atoms, or a maleimide, and may be any one of an ether, ester, lactone, or carboxylic anhydride. R5 and R6 are any one of a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R7 is any one of a hydrogen atom, a straight-chain, branched, cyclic alkyl group with 1 to 6 carbon atoms, a hydroxyl group, or an alkoxycarbonyl group. p and q are integers from 1 to 4. r is an integer from 0 to 4. a, b, and c represent the ranges of 0.5≤a+b+c≤1, 0≤a≤0.8, 0≤b≤0.8, 0.1≤a+b≤0.8, and 0.1≤c≤0.8, respectively. It should be noted that the symbols in the formula only apply to that specific formula.

[0048] [Chemical 6] In formula (7), R1 represents a hydrogen atom or a monovalent organic group, and R2 and R3 independently represent monovalent atoms or monovalent organic groups. It should be noted that the symbols in the formula are only applicable in this formula.

[0049] Specifically, examples of resins containing the following structures described in Japanese Patent Application Publication Nos. 2004-205685, 2007-171895, and 2009-14816 can be cited as suitable for the organic film forming resin of the present invention. [Chemical 7] In formulas (8) and (9), R1 to R8 are independently hydrogen atoms, hydroxyl groups, substituted alkyl groups having 1 to 6 carbon atoms, substituted alkoxy groups having 1 to 6 carbon atoms, substituted alkoxy carboxyl groups having 2 to 6 carbon atoms, substituted aryl groups having 6 to 10 carbon atoms, hydroxyalkyl groups having 1 to 6 carbon atoms, isocyanate groups, or glycidyl groups. m and n are positive integers. It should be noted that the symbols in the formulas are only applicable to the formulas in which they are used.

[0050] [Chemical 8] In formula (10), R1 and R6 are hydrogen atoms or methyl groups. R2, R3, and R4 are hydrogen atoms, alkyl groups with 1 to 4 carbon atoms, alkoxy groups, hydroxyl groups, acetoxy groups or alkoxy carbonyl groups, or aryl groups with 6 to 10 carbon atoms. R5 represents a condensed polycyclic hydrocarbon group with 13 to 30 carbon atoms, -O-R7-C(=O)-O-R7-OC(=O)-R7 or -C(=O)-NR8-R7, m is 1 or 2, n is an integer from 0 to 4, and p is an integer from 0 to 6. R7 is an organic group with 7 to 30 carbon atoms, and R8 is a hydrogen atom or a hydrocarbon group with 1 to 6 carbon atoms. Z is any one of methylene, -O-, -S-, and -NH-. a, b, c, d, and e represent the ranges of 0 < a < 1.0, 0 ≤ b ≤ 0.8, 0 ≤ c ≤ 0.8, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.8, and 0 < b + c + d + e < 1.0, respectively. It should be noted that the symbols in the formula only apply to that specific formula.

[0051] [Chemical 9] In formula (11), n ​​represents 0 or 1. R1 represents a substituted methylene, a substituted alkyl group having 2 to 20 carbon atoms, or a substituted aryl group having 6 to 20 carbon atoms. R2 represents a hydrogen atom, a substituted alkyl group having 1 to 20 carbon atoms, or a substituted aryl group having 6 to 20 carbon atoms. R3 to R7 represent a hydroxyl group, a substituted alkyl group having 1 to 6 carbon atoms, a substituted alkoxy group having 1 to 6 carbon atoms, a substituted alkoxycarbonyl group having 2 to 10 carbon atoms, a substituted aryl group having 6 to 14 carbon atoms, or a substituted glycidyl ether group having 2 to 6 carbon atoms. R9 represents a hydrogen atom, a straight-chain, branched, or cyclic alkyl group having 1 to 10 carbon atoms, a straight-chain, branched, or cyclic alkyl ether group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms. It should be noted that the symbols in the formula are only applicable in this formula.

[0052] For example, the following compounds can be exemplified. [Chemical 10]

[0053] As an organic film-forming resin suitable for the present invention, examples include resins containing the following structure as described in Japanese Patent Application Publication No. 2007-199653, Japanese Patent Application Publication No. 2008-274250, and Japanese Patent Application Publication No. 2010-122656. [Chemical 11] In formula (12), R1 and R2 are independently the same or different kinds of hydrogen atoms, straight-chain, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, aryl groups having 6 to 10 carbon atoms, or alkenyl groups having 2 to 10 carbon atoms; R3 is a single bond, or a straight-chain, branched, or cyclic alkyl group having 1 to 30 carbon atoms, and may have a bridged cyclic hydrocarbon group, a double bond, a heteroatom, or an aromatic group having 6 to 30 carbon atoms; R4 and R5 are each independently hydrogen atoms or glycidyl groups; and n is an integer from 1 to 4. It should be noted that the symbols in the formula are only applicable in this formula.

[0054] [Chemical 12] In formula (13), R1 and R2 are independently the same or different kinds of hydrogen atoms, straight-chain, branched, or cyclic alkyl groups with 1 to 10 carbon atoms, aryl groups with 6 to 10 carbon atoms, or alkenyl groups with 2 to 10 carbon atoms; R3 is a single bond, or a straight-chain, branched, or cyclic alkyl group with 1 to 30 carbon atoms, which may have a bridged cyclic hydrocarbon group, a double bond, a heteroatom, or an aromatic group with 6 to 30 carbon atoms; R4 and R5 are each independently hydrogen atoms or glycidyl groups; and R6 is a single bond, or a straight-chain or branched alkyl group with 1 to 10 carbon atoms. It should be noted that the symbols in the formula are only applicable in this formula.

[0055] [Chemical 13] In formula (14), ring Z1 and ring Z2 are condensed polycyclic aromatic rings, and R1a, R1b, R2a, and R2b represent the same or different substituents. k1 and k2 are the same or different, representing integers from 0 to 4, m1 and m2 represent integers greater than or equal to 1, and n1 and n2 represent integers greater than or equal to 1. Wherein, n1 + n2 ≥ 1. It should be noted that the symbols in the formula are only applicable in this formula.

[0056] [Chemical 14] In formula (15), R1 and R2 are the same or different types of hydrogen atoms, straight-chain, branched, or cyclic alkyl groups with 1 to 10 carbon atoms, aryl groups with 6 to 10 carbon atoms, and alkenyl groups with 2 to 10 carbon atoms. R3 and R4 are hydrogen atoms or glycidyl groups, respectively. R5 is a single bond, a straight-chain or branched alkyl group with 1 to 10 carbon atoms, and R6 and R7 are benzene rings and naphthalene rings. p and q are 1 or 2, respectively. n is 0 < n ≤ 1. It should be noted that the symbols in the formula are only applicable to this formula.

[0057] For example, the following compounds can be exemplified. [Chemical 15]

[0058] [Chemical 16]

[0059] [Chemical 17]

[0060] [Chemical 18]

[0061] As an organic film-forming resin suitable for the present invention, examples include the resin containing the following structure disclosed in Japanese Patent Application Publication No. 2012-214720. [Chemical 19] In formula (16), the ring structures Ar1 and Ar2 represent benzene rings or naphthalene rings. x and z each independently represent 0 or 1. It should be noted that the symbols in the formula are only applicable in this formula.

[0062] Resins suitable for forming organic films according to the present invention include those described in Japanese Patent Application Publication No. 2014-29435, International Publication No. WO2012 / 077640, and International Publication No. WO2010 / 147155. [Chemical 20] In formula (17), A represents a structure having a carbazole, B represents a structure having an aromatic ring, and C represents a hydrogen atom, an alkyl group, or a structure having an aromatic ring. B and C can form a ring with each other. The structure combining A, B, and C has 1 to 4 carboxyl groups or their salts, or carboxylic acid ester groups. It should be noted that the symbols in the formula are only applicable in this formula.

[0063] In addition, examples can be listed in International Publication WO2012 / 077640, which contain the unit structures shown in the following formula (18) and the following formula (19), wherein the ratio of the unit structure shown in formula (18) to the unit structure shown in formula (19) is 3 to 97 to 3 in molar ratio. [Chemical 21] In formula (18), R1 and R2 each independently represent a hydrogen atom, a halogen atom, a nitro group, an amino group, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, or a combination of these groups that may contain ether bonds, ketone bonds, or ester bonds. R3 represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, or a combination of these groups that may contain ether bonds, ketone bonds, or ester bonds. R4 represents a hydrogen atom, or an aryl or heterocyclic group with 6 to 40 carbon atoms that can be substituted with a halogen atom, nitro, amino, or hydroxyl group. R5 represents a hydrogen atom, or an alkyl, aryl, or heterocyclic group with 1 to 10 carbon atoms that can be substituted with a halogen atom, nitro, amino, or hydroxyl group. R4 and R5 can form a ring with each other. n1 and n2 represent integers from 1 to 3. It should be noted that the symbols in the formula are only applicable to this formula.

[0064] [Chemical 22] In formula (19), Ar represents an aromatic cyclic group with 6 to 20 carbon atoms, R6 represents a hydroxyl group, and R7 represents a hydrogen atom, a halogen atom, a nitro group, an amino group, an alkyl group with 1 to 10 carbon atoms, an alkenyl group with 2 to 10 carbon atoms, an aryl group with 6 to 40 carbon atoms, or a combination of these groups that may contain ether bonds, ketone bonds, or ester bonds. R8 represents a hydrogen atom, or an aryl group with 6 to 40 carbon atoms that may be substituted by a halogen atom, a nitro group, an amino group, or a hydroxyl group, or a heterocyclic group. R9 represents a hydrogen atom, or an alkyl group with 1 to 10 carbon atoms, an aryl group with 6 to 40 carbon atoms that may be substituted by a halogen atom, a nitro group, an amino group, or a hydroxyl group, and R8 and R9 may form a ring with each other. n6 represents an integer from 1 to p, and n7 represents an integer from p to n6. Here, p represents the largest number that can be substituted on the aromatic cyclic group Ar. It should be noted that the symbols in the formula are only applicable to this formula.

[0065] As the organic film-forming resin applicable to the present invention, a polymer containing the unit structure represented by the following formula (20) as described in International Publication No. WO2010 / 147155 may be used. [Chemical 23] In formula (20), R1 and R2 are respectively selected from the group consisting of hydrogen atoms, halogen groups, nitro groups, amino groups, hydroxyl groups, alkyl groups having 1 to 10 carbon atoms, alkenyl groups having 2 to 10 carbon atoms, aryl groups having 6 to 40 carbon atoms, and combinations thereof, and the alkyl group, alkenyl group, or aryl group represents a group that may contain ether bonds, ketone bonds, or ester bonds, and R3 represents a group consisting of hydrogen atoms, alkyl groups having 1 to 10 carbon atoms, alkenyl groups having 2 to 10 carbon atoms, aryl groups having 6 to 40 carbon atoms, and combinations thereof. The group is defined as follows: R4 represents an aryl or heterocyclic group with 6 to 40 carbon atoms that can be substituted with a halogen group, nitro group, amino group, or hydroxyl group; R5 represents a hydrogen atom, or an alkyl group with 1 to 10 carbon atoms, an aryl group with 6 to 40 carbon atoms that can be substituted with a halogen group, nitro group, amino group, or hydroxyl group; and R4 and R5 can form a ring together with the carbon atoms to which they are bonded. n1 and n2 are integers from 1 to 3. It should be noted that the symbols in the formula are only applicable in this formula.

[0066] As an organic film-forming resin suitable for the present invention, examples include phenolic varnish resins obtained by reacting one or more of phenols such as phenol, cresol, xylenol, catechol, resorcinol, hydroquinone, pyrogallol, hydroxyhydroquinone, and resorcinol with one or more of aldehyde sources such as formaldehyde, paraformaldehyde, and trimethylolpropane using an acidic catalyst; and resins containing repeating unit structures as shown in International Publication No. WO2012 / 176767, etc. [Chemical 24] In formula (21), A represents a hydroxylated extended phenyl group derived from polyhydroxybenzene, and B represents a monovalent condensed aromatic hydrocarbon cyclogroup formed by the condensation of 2 to 6 benzene rings. It should be noted that the symbols in the formula are only applicable in this formula.

[0067] Examples of phenolic varnish resins having a fusiform or tetrahydrospirodiinden structure, as described in Japanese Patent Application Publication Nos. 2005-128509, 2006-259249, 2006-259482, 2006-293298, and 2007-316282, may include resins containing repeating unit structures as shown in formula (22-1) or (22-2). [Chem. 25] In formulas (22-1) and (22-2), R1, R2, R6, and R7 are independently hydrogen atoms, straight-chain, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, aryl groups having 6 to 10 carbon atoms, allyl groups, or halogen atoms; R3, R4, R8, and R9 are independently hydrogen atoms, straight-chain, branched, or cyclic alkyl groups having 1 to 6 carbon atoms, straight-chain, branched, or cyclic alkenyl groups having 2 to 6 carbon atoms, aryl groups having 6 to 10 carbon atoms, or glyoxypropyl groups; R5 and R14 are independently hydrogen atoms, straight-chain, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, or aryl groups having 6 to 10 carbon atoms. n, m, p, and q are integers from 1 to 3. R10 to R13 are independently hydrogen atoms, halogen atoms, hydroxyl groups, straight-chain, branched, or cyclic alkyl groups having 1 to 6 carbon atoms, or straight-chain, branched, or cyclic alkoxy groups having 1 to 6 carbon atoms. It should be noted that the symbols in the formula are only applicable to this specific formula.

[0068] As an organic film-forming resin suitable for the present invention, the reaction product obtained by the method described in Japanese Patent Application Publication No. 2012-145897 can be exemplified. More specifically, a polymer obtained by condensing one or more compounds represented by the following general formula (23-1) and / or (23-2) with one or more compounds represented by the following general formula (24-1) and / or (24-2) and / or their equivalents can be exemplified. [Chemical 26] In formulas (23-1) and (23-2), R1 to R8 are independently hydrogen atoms, halogen atoms, hydroxyl groups, isocyanate groups, epoxypropoxy groups, carboxyl groups, amino groups, alkoxy groups with 1 to 30 carbon atoms, alkoxycarbonyl groups with 1 to 30 carbon atoms, alkoxy groups with 1 to 30 carbon atoms, and substituted saturated or unsaturated organic groups with 1 to 30 carbon atoms. Furthermore, within the molecule, any two substituents chosen from R1~R4 or R5~R8 can bond to further form a cyclic substituent. It should be noted that the symbols in the formula are only applicable to this specific formula. [Chem. 27] In formulas (24-1) and (24-2), Q is an organic group with 1~30 carbon atoms that can be substituted, and any two Qs chosen within the molecule can bond to form a cyclic substituent. n1~n6 are the number of each substituent, n1~n6=0, 1, 2, except for hydroxybenzaldehyde in formula (24-1). Additionally, in formula (24-2), the relationships 0≤n3+n5≤3, 0≤n4+n6≤4, and 1≤n3+n4≤4 are satisfied. It should be noted that the symbols in the formula are only applicable to this specific formula.

[0069] In addition, examples can be given of polymers obtained by condensing one or more compounds represented by the general formula (23-1) and / or general formula (23-2), one or more compounds represented by the general formula (24-1) and / or general formula (24-2) and / or their equivalents, with one or more compounds represented by the general formula (25) below and / or their equivalents. [Chemical 28] In formula (25), Y is a hydrogen atom or a monovalent organic group with 30 or fewer carbon atoms that may have substituents. Formula (25) is different from formulas (24-1) and (24-2). It should be noted that the symbols in the formula are only applicable in this formula.

[0070] As an organic film-forming resin suitable for the present invention, examples include resins containing the following structures as described in Japanese Patent Application Publication No. 2017-119671. [Chemical 29] In formula (26-1), R is a single bond or an organic group having 1 to 50 carbon atoms, X is a group shown in the following general formula (26-2), and m1 is an integer satisfying 2 ≤ m1 ≤ 10. It should be noted that the symbols in the formula are only applicable in this formula. [Chemical 30] In the formula, X2 is a divalent organic group having 1 to 10 carbon atoms, n1 is 0 or 1, n2 is 1 or 2, X3 is a group shown in the following general formula (26-3), and n5 is 0, 1, or 2. It should be noted that the symbols in the formula are only applicable in this formula. [Chemical 31] Wherein R10 is a hydrogen atom or a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms, and the hydrogen atom on the benzene ring in the formula can be replaced by a methyl or methoxy group. It should be noted that the symbols in the formula are only applicable in this formula.

[0071] For example, the following compounds can be exemplified. [Chemical 32]

[0072] As an organic film-forming resin suitable for the present invention, examples include polymers having repeating units as shown in the following general formula (27-1) as described in Japanese Patent Application Publication No. 2019-44022. [Chemical 33] In formula (27-1), AR1 and AR2 are benzene rings or naphthalene rings that may have substituents, and R1 and R2 are each independently hydrogen atoms or organic groups having 1 to 30 carbon atoms. When R1 and R2 are organic groups, R1 and R2 can form cyclic organic groups by intramolecular bonding. n is 0 or 1. When n=0, AR1 and AR2 do not form a bridging structure between the aromatic rings of AR1 and AR2 via Z. When n=1, AR1 and AR2 form a bridging structure between the aromatic rings of AR1 and AR2 via Z. Z is a single bond or any of the following formula (27-2). Y is a group shown in the following formula (27-3). It should be noted that the symbols in the formula are only applicable in this formula. [Chem. 34][Chem. 35] Where R3 is a single bond or a divalent organogroup with 1 to 20 carbon atoms, R4 is a hydrogen atom or a monovalent organogroup with 1 to 20 carbon atoms, and the dashed line represents the connecting bond. It should be noted that the symbols in the formula are only applicable in this formula.

[0073] For example, the following polymers can be exemplified. [Chemical 36]

[0074] [Chemical 37]

[0075] The resin for forming organic films can be synthesized using known methods or commercially available products can be used.

[0076] The amount of resin used for forming organic films is, for example, 0.2 to 50 parts by mass relative to 100 parts by mass of the composition for forming organic films, and more preferably 1 to 33.3 parts by mass.

[0077] The composition for forming organic films only needs to contain an organic film forming resin and a solvent, and may also contain additives such as crosslinking agents, acid generating agents, and surfactants.

[0078] As a solvent that can be used in the composition for forming organic films, there are no particular restrictions as long as it can dissolve the resin for forming organic films. It is preferable that it can also dissolve the acid generator, crosslinking agent, surfactant, etc. mentioned below. Specifically, examples include ketones such as 2-heptanone, cyclopentanone, and cyclohexanone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; and esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tributyl acetate, tributyl propionate, γ-butyrolactone, and propylene glycol monotert-butyl ether acetate. One or more of these can be used, but the use is not limited to these.

[0079] Preferably, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, 2-heptanone, cyclopentanone, cyclohexanone, γ-butyrolactone, and mixtures of two or more thereof are used.

[0080] As a usable solvent, a solvent with a standard boiling point of 80°C or higher and less than 160°C may be used.

[0081] The amount of solvent incorporated relative to 100 parts by weight of the resin for forming organic films is preferably 100 to 50,000 parts by weight, and more preferably 200 to 10,000 parts by weight.

[0082] [Other components] Furthermore, acid generating agents, crosslinking agents, etc., may be added to the organic film forming composition to further promote the crosslinking reaction.

[0083] As an acid generating agent, there are acid generating agents that generate acid by thermal decomposition and acid generating agents that generate acid by light irradiation, both of which can be added. Specifically, the acid generating agents described in paragraphs (0061) to (0085) of Japanese Patent Application Publication No. 2007-199653 can be cited as examples. The amount of acid generating agent added is not particularly limited, for example, it can be set to 0.05 to 50 parts by mass relative to 100 parts by mass of the resin for forming organic films.

[0084] Furthermore, as a crosslinking agent, specifically, the crosslinking agent described in paragraphs (0055) to (0060) of Japanese Patent Application Publication No. 2007-199653 can be cited. The amount of crosslinking agent is not particularly limited, for example, it can be set to 1 to 50 parts by mass relative to 100 parts by mass of the resin for forming organic films.

[0085] Furthermore, in order to improve the coatability of the organic film forming composition, a surfactant may also be added. Specifically, the surfactant described in paragraphs (0142) to (0147) of Japanese Patent Application Publication No. 2009-269953 can be cited as an example. The amount of surfactant added is not particularly limited, for example, it can be set to 0.001 to 20 parts by mass relative to 100 parts by mass of the organic film forming resin.

[0086] Furthermore, basic compounds may be added to the composition for forming organic films to enhance storage stability. These act as acid quenchers to prevent trace amounts of acid generated by the acid generator from promoting cross-linking. Specifically, the basic compounds described in paragraphs (0086) to (0090) of Japanese Patent Application Publication No. 2007-199653 can be cited as examples of such basic compounds.

[0087] [Coating Solvent Application Step] In the method for forming the organic film of the present invention, after forming the coated film and before the insoluble treatment, a coating solvent with a standard boiling point of 160°C or higher and less than 500°C is spin-coated onto the coated film. The method of applying the coating solvent is not particularly limited, and known methods such as using a spin coater can be used. It should be noted that, as a spin coating method, either static or dynamic distribution can be employed.

[0088] In the organic film formation method of the present invention, the coating film before the aforementioned insoluble treatment is dissolved in the aforementioned coating solvent, and the resin component in the uncured coating film can obtain sufficient thermal fluidity. Therefore, it is considered that a resist lower layer film with excellent filling / planarization characteristics can be formed. Therefore, it is necessary for the coating film before the aforementioned insoluble treatment to dissolve in the aforementioned coating solvent. Specifically, on a substrate without a pattern, when the film thickness of the coating film before the insoluble treatment formed by spin coating using the aforementioned organic film forming composition is defined as a, and the film thickness of the organic film formed by spin coating the aforementioned coating solvent onto the coating film and then performing a heat treatment at 100°C for 60 seconds is defined as b, the upper limit of the b / a ratio is preferably 99.5% or less, more preferably 99% or less, and even more preferably 98% or less. The lower limit of the b / a ratio is preferably 30% or more, more preferably 40% or more, and even more preferably 50% or more.

[0089] By dissolving the coating film before the insoluble treatment in the coating solvent within the above-mentioned range, the resin component contained in the coating film can obtain sufficient thermal fluidity. If the upper limit of the b / a ratio is 99.5% or less, the resin component contained in the coating film can obtain sufficient thermal fluidity; if the lower limit of the b / a ratio is 30% or more, excessive thinning can be suppressed, which is therefore preferable from the viewpoint of a resistance-saving agent.

[0090] The coating solvent is an organic solvent with a standard boiling point of 160°C or higher and less than 500°C. It is acceptable as long as it is liquid when used in the coating solvent application step, preferably liquid at room temperature (25°C). There are no particular restrictions on alcohols, esters, ketones, carbonates, ethers, amides, chlorinated solvents, etc. From the viewpoint of compatibility with the coating film, alcohols, esters, ketones, carbonates, ethers, or combinations thereof are preferred. As specific examples, examples of alcohols include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propanediol, 1,3-butanediol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, and glycerol; examples of ethers include monohexyl ether and ethylene glycol mono-2-ethylhexyl ether. Ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monon-butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol n-butyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monon-propyl ether, dipropylene glycol Monobutyl ether, tripropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol mono-n-propyl ether, tripropylene glycol mono-n-butyl ether; examples of esters include nonyl acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, glyceryl triacetate, propylene glycol diacetate, dipropylene glycol methyl propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1,3-butanediol diacetate, etc. Diacetyl alcohol, 1,6-hexanediol diacetate, triethylene glycol diacetate, γ-butyrolactone, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, dibutyl adipate; as ketones, examples include ethylpentyl ketone, dibutyl ketone, and dipentyl ketone; as carbonates, examples include ethyl carbonate and propyl carbonate. They can be used alone or in combination.

[0091] The standard boiling point of the aforementioned coating solvent must be above 160°C and below 500°C, preferably above 180°C and below 200°C and below 400°C. If it deviates from the above boiling point range, the resin component in the uncured coating film cannot obtain sufficient thermal fluidity, and it cannot form a resistive underlayer film with excellent filling / planarization characteristics. In addition, if it is such a boiling point, it will not remain in the film without volatilization after insolubilization treatment, and therefore will not adversely affect the film properties such as etching resistance.

[0092] The coating solvent may be different from or the same as the organic solvent contained in the coating film (derived from the organic solvent contained in the composition for forming the organic film), but it is preferable to have a standard boiling point that is higher than that of the organic solvent contained in the coating film. Such a coating solvent is less volatile than the organic solvent contained in the coating film, so that during the insoluble treatment, the resin component in the uncured coating film exhibits suitable thermal fluidity, and a film with better filling / planarization characteristics can be formed.

[0093] If the solubility and wettability of organic films are taken into consideration, it is preferable to use an aromatic compound having a benzyl or benzoyl group.

[0094] Particularly preferred are aromatic compounds such as: (i) polyethylene glycol dibenzoate; (ii) polyethylene glycol dibenzyl ether; (iii) polypropylene glycol dibenzyl ether; (iv) polybutylene glycol dibenzyl ether; (v) linear aliphatic dicarboxylic acid dibenzyl ester; (vi) polyethylene glycol monobenzyl ether; (vii) polyphenyl ether; (viii) alkyl benzyl phthalate.

[0095] [Chemical 38] It should be noted that n in the above formula is an integer in the range of 150 to 500 for molecular weight, and is only applicable in this formula.

[0096] When coating the coating solvent onto the coating film, there is no particular limitation on the amount of coating solvent, but it is preferably 0.5 ml or more and 20 ml or less, more preferably 1 ml or more and 15 ml or less, and even more preferably 1.5 ml or more and 10 ml or less.

[0097] [Organic Film Formation Step] The organic film formation step is a step that forms an organic film by performing an insoluble treatment on the coated film relative to the coating solvent after the above-described coating solvent application step. In the organic film formation method of the present invention, the coated film before the insoluble treatment is in an uncured or incompletely cured state. By dissolving the resin component in the coated film in the coating solvent, the resin component in the uncured or incompletely cured coated film can obtain sufficient thermal fluidity. Conversely, the coated film after the insoluble treatment is in a cured state, and the resin component in the coated film does not dissolve in the coating solvent, thus lacking thermal fluidity. This forms an organic film. It should be noted that, as described above, the coating solvent application method is not particularly limited, and both static and dynamic distribution methods can be used.

[0098] [Insolubility Treatment] In the method for forming the organic film of the present invention, after forming the coating film, the coating film is subjected to an insolubility treatment relative to the coating solvent. The insolubility treatment is not particularly limited, as long as the resin component in the coating film becomes insoluble in the coating solvent, and preferably is any one or a combination of heat treatment at 100°C or higher and 600°C or lower, UV irradiation treatment at 400 nm or lower (phototreatment), electron beam irradiation treatment (electron beam treatment), and plasma irradiation treatment (plasma treatment). By performing the insolubility treatment in this manner, an organic film that maintains a flat state can be formed.

[0099] [Heat Treatment] The heat treatment is performed within a temperature range of 100°C to 600°C, preferably 150°C to 550°C, and more preferably 180°C to 500°C, for 10 to 600 seconds, preferably 10 to 300 seconds. By appropriately adjusting the baking temperature and time within the above range, planarization / filling characteristics, as well as hardening properties such as dry etching resistance and heat resistance suitable for the application can be obtained. When the baking temperature is above 100°C, hardening is sufficient and mixing with the upper or intermediate resist film is not produced. If the baking temperature is below 600°C, thermal decomposition of the base resin can be suppressed, the film thickness will not decrease, and the film surface becomes uniform.

[0100] The baking environment can be selected from either a moderately oxygenated air environment (oxygen concentration 1%~21%) or a moderately oxygen-free nitrogen environment, depending on the needs. For example, when the substrate being processed is easily oxidized by air, heat treatment in an environment with an oxygen concentration of less than 1% can be used to form a hardened film, which can suppress substrate damage. It should be noted that the unit is volume%.

[0101] [Light Processing] The exposure light used for light processing is a chemical ray such as near-ultraviolet, far-ultraviolet, or extreme ultraviolet (e.g., EUV, 13.5 nm). For example, light wavelengths such as 248 nm (KrF laser), 193 nm (ArF laser), 172 nm (xenon excimer light), and 157 nm (F2 laser) can be used. Alternatively, exposure wavelengths below 400 nm can be used, especially ultraviolet light in the range of 10 nm to 380 nm, with wavelengths of 10 to 200 nm being preferred.

[0102] This exposure is used to crosslink the resin contained in the coated film. The exposure amount is in the range of 10 mJ / cm2 to 10,000 mJ / cm2. Under exposure amounts within this range, a photoreaction occurs, crosslinking is formed, and resistance to organic solvents is generated.

[0103] [Electron Beam Processing] Electron beam irradiation can be performed using known methods. For example, the method described in "Technology and Utilization of Electron Beam Irradiation Apparatus" (July 2012, SEI Technical Review, No. 181, pp. 50-57, Non-Patent Literature) can be cited. The accelerating voltage can be selected from 2 to 200 kV. The irradiation dose can be selected from 100 to 5,000 kGy. In this case, electron beam irradiation is preferably performed while heating. In this case, the temperature can be selected from 80°C to 800°C (preferably 200°C to 700°C, more preferably 300°C to 600°C). Ion irradiation can be performed using known methods. For example, the method described in "Raman spectroscopy and microhardness of ion-implanted aC:H-films" (Ceramics Int. 26(1), 2000, pp. 29-32, Non-Patent Literature). A preferred method of ion irradiation of the present invention is ion implantation. Examples of elements that can be used for irradiation include hydrogen, boron, carbon, nitrogen, and noble gases; preferred elements include boron, carbon, nitrogen, neon, and argon; further preferred elements include carbon and nitrogen. Two or more of these gases can be mixed. The accelerating voltage can be selected from 3 to 1000 kV. A preferred accelerating voltage is 5 to 750 kV, more preferably 10 to 500 kV. The irradiation dose can be selected from 10¹³ to 10¹⁸ ions / cm². A more preferred irradiation dose is 5 × 10¹³ to 5 × 10¹⁷ ions / cm², and further preferably 10¹⁴ to 10¹⁷ ions / cm². Ion irradiation can also be performed while the chamber of the apparatus is heated. In this case, the temperature can be selected to be below 500°C. When heating occurs after plasma or electron beam irradiation, the heating conditions are appropriately selected from a range of 80–800°C (preferably 200–700°C, more preferably 300–600°C) and a heating time of 30–180 seconds (preferably 30–120 seconds). Without being bound by theory, it is believed that high-temperature heating after plasma or electron beam irradiation can facilitate dangling bond formation, contributing to the high density of the hardened film.

[0104] As an irradiation device, Tactras Vigus, EB-ENGINE (Hamamatsu Photonics), and EXCEED2300AH (Nisshin Ionizer) can be used. The device and setting conditions can be selected in a way that achieves the effects of the present invention.

[0105] [Plasma Treatment] Plasma irradiation can be performed using known methods. For example, the method described in Japanese Patent No. 5746670, "Improvement of the wiggling profile of spin-on carbon hard mask by H2plasma treatment" (J. Vac. Sci. Technol. B26(1), Jan / Feb 2008, pp. 67-71).

[0106] The preferred RF discharge power is 100~10,000W, and the more preferred power is 500~5,000W.

[0107] Examples of suitable gaseous environments include rare gases such as N2, NF3, H2, and He, as well as fluorinated hydrocarbons; more preferably, they include He, Ar, N2, Ne, NF3, H2, CF4, CHF3, CH2F2, CH3F, C4F6, and C4F8. Two or more of these gases can also be mixed. An O2 gaseous environment is also expected to provide the benefits of this invention, which is an advantage of this invention.

[0108] The plasma irradiation time can be selected from, for example, 10 to 240 seconds. The pressure can be selected appropriately.

[0109] The plasma irradiation is preferably carried out in an environment containing rare gases such as N2, NF3, H2, fluorides, He, or any mixture thereof.

[0110] From a productivity point of view, He, Ar, N2, H2, etc. are particularly good gas environments.

[0111] Heat treatment can be performed before or after plasma irradiation. When heating is performed before plasma irradiation, the heating temperature can be appropriately selected from the range of 80~400℃ (preferably 100~350℃, more preferably 150~300℃) and the heating time from 30~180 seconds (preferably 30~120 seconds). When heating is performed after plasma irradiation, the heating temperature can be appropriately selected from the range of 80~800℃ (preferably 100~700℃, more preferably 200~600℃) and the heating time from 30~180 seconds (preferably 30~120 seconds). Without being bound by theory, it is believed that high-temperature heating after plasma irradiation can facilitate the bonding of dangling bonds, contributing to the high density of the hardened film (resistor underlayer film).

[0112] As the environment for heating after plasma irradiation, either a moderately oxygenated environment in air (oxygen concentration of 1% to 21% by volume) or a moderately oxygen-free environment in nitrogen (oxygen concentration of less than 1% by volume) can be selected as needed. For example, when the substrate being processed is easily oxidized by air, heat treatment in an environment with an oxygen concentration of less than 1% by volume can be used to form a hardened film, thereby suppressing substrate damage.

[0113] As for the irradiation device, there are no particular limitations as long as it is capable of plasma irradiation. For example, the Telius SP and Tactus Vigus manufactured by Tokyo Power Technology Co., Ltd. can be used. The device and setting conditions can be selected in a way that can more significantly exert the effects of the present invention.

[0114] Through the steps described above, an insoluble organic film can be formed on a substrate with an uneven pattern. Here, the thickness of the organic film is appropriately selected according to the depth of the pattern, preferably 10 to 20,000 nm, and particularly preferably 20 to 15,000 nm.

[0115] When the organic film formed in this way is applied to the multilayer resist treatment, inorganic hard masks such as a resist intermediate film containing a silicon film, a resist upper layer film without a silicon film (single-layer resist film), a silicon oxide film, a silicon oxynitride film, amorphous silicon film, or titanium oxynitride film can be formed on it. In addition, since the substrate can be planarized to a high degree even without using the high-cost CMP process, substrate planarization can be performed at a low cost.

[0116] <Method for Manufacturing a Substrate for a Semiconductor Device> The present invention provides a method for manufacturing a substrate for a semiconductor device, wherein an organic film is formed on a substrate having an uneven pattern using the above-described method for forming an organic film; a silicon-containing resist intermediate film is formed on the organic film using a silicon-containing resist intermediate film forming composition; a resist upper layer film is formed on the silicon-containing resist intermediate film using a photoresist composition; a circuit pattern is formed on the resist upper layer film; the resist upper layer film with the pattern is used as a mask; the pattern is transferred to the silicon-containing resist intermediate film by dry etching; the silicon-containing resist intermediate film with the transferred pattern is used as a mask; the pattern is transferred to the organic film by dry etching; and the organic film with the transferred pattern is used as a mask; the pattern is transferred to the substrate by dry etching.

[0117] The substrate used in the manufacturing method of the semiconductor device substrate of the present invention preferably comprises a metal film, a metal carbide film, a metal oxide film, a metal nitride film or a metal oxynitride film.

[0118] In addition, the metal constituting the substrate is preferably silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, molybdenum or alloys thereof.

[0119] In the above-mentioned method for manufacturing a substrate for a semiconductor device, the organic film can also be used as a sacrificial film.

[0120] Preferably, the substrate with the above-mentioned uneven pattern has an open area (non-patterned area) and patterned areas with densities (DENSE) and sparse areas (ISO), and the aspect ratio of the pattern is 0.1 to 10. In addition, the bias (coating height difference) between the open area and the patterned area is preferably 1 to 100 nm.

[0121] As a composition for forming organic films, it is preferable to use compositions containing aromatic rings as described above. In 193nm exposure applications, if a material containing more aromatic groups and with high substrate etching resistance is used, the k-value becomes higher, resulting in higher substrate reflectance. However, by using a silicon resist-containing interlayer to suppress reflection, the substrate reflectance can be set to 0.5% or less. Furthermore, in extreme ultraviolet (EUV) exposure, if an organic film material containing more aromatic groups and with high substrate etching resistance is used, fine patterns can be formed.

[0122] As a silicon-containing resist interlayer, a polysiloxane-based coating film is preferred. By giving the silicon-containing resist interlayer the effect of acting as an anti-reflective film, reflection can be suppressed. Specifically, examples include silicon-containing resist interlayers obtained from compositions shown in Japanese Patent Application Publication Nos. 2004-310019, 2007-302873, and 2009-126940.

[0123] Furthermore, the photoresist composition used to form the upper resist film can be either positive or negative, and the same photoresist composition as commonly used photoresist compositions can be used. When forming the upper resist film using the above-described photoresist composition, spin coating is preferred, similar to the method used when forming the above-described organic film. After spin coating the photoresist composition, pre-baking is performed, preferably at 60-180°C for 10-300 seconds. Then, exposure is performed according to conventional methods, followed by post-exposure baking (PEB) and development to obtain a resist pattern (circuit pattern). Furthermore, the thickness of the upper resist film is not particularly limited, but is preferably 30-500 nm, and particularly preferably 50-400 nm.

[0124] Furthermore, in the formation of the circuit pattern, it is preferable to use any one or a combination of high-energy rays with wavelengths of 10 nm or more and 300 nm or less, direct drawing based on electron beams, and nanoimprinting to form the circuit pattern.

[0125] As exposure light, high-energy rays with wavelengths below 300nm can be cited, specifically excimer lasers of 248nm, 193nm, and 157nm, soft X-rays of 3~20nm, so-called EUV light, electron beams, X-rays, etc.

[0126] In addition, in the formation of the circuit pattern, it is preferable to develop the circuit pattern using alkaline development or organic solvent development.

[0127] Next, the obtained resist pattern is used as a mask for etching. The dry etching process of the silicon resist intermediate film can be performed, for example, using a Freon-based gas and the resist pattern as a mask. Next, the silicon resist intermediate film pattern (the silicon resist intermediate film with the transferred pattern) is used as a mask, and the organic film is dry etched using, for example, oxygen or hydrogen.

[0128] The subsequent etching of the substrate can also be carried out using conventional methods. For example, if the substrate is a SiO2, SiN, or silicon dioxide-based low dielectric constant insulating film, etching with Freon-based gas is used. If the substrate is p-Si, Al, or W, etching with chlorine-based or bromine-based gas is used, which can transfer the pattern to the substrate.

[0129] Alternatively, an organic antireflective film (BARC) can be formed on the above-mentioned silicon-containing intermediate film, and then an upper layer of the resistive film can be formed on it. That is, the present invention provides a method for manufacturing a substrate for a semiconductor device, which involves forming an organic film on a substrate having a raised or recessed pattern using the organic film formation method of the present invention described above; forming a silicon-containing resist intermediate film using a silicon-containing resist intermediate film formation composition on the organic film; forming an organic anti-reflective film on the silicon-containing resist intermediate film; forming a resist upper film using a photoresist composition on the organic anti-reflective film to form a resist upper film, thereby forming four resist films; forming a circuit pattern on the aforementioned resist upper film; using the resist upper film with the pattern formed thereon as a mask; transferring the pattern to the aforementioned organic anti-reflective film and the aforementioned silicon-containing resist intermediate film using dry etching; using the organic anti-reflective film and the silicon-containing resist intermediate film with the transferred pattern as a mask; transferring the pattern to the aforementioned organic film using dry etching; and then using the organic film with the transferred pattern as a mask; transferring the pattern to the aforementioned substrate using dry etching.

[0130] Furthermore, except for forming an organic antireflective film on the silicon resist-containing intermediate film, this method can be performed in the same manner as the manufacturing method of a semiconductor device substrate using the aforementioned silicon resist-containing intermediate film. There are no particular limitations on the organic antireflective film; a known organic antireflective film can be used, and it can be formed using known methods such as spin coating.

[0131] Alternatively, inorganic hard masks such as silicon oxide films, silicon nitride films, silicon oxynitride films, amorphous silicon films, or titanium nitride films can also be formed on the above-mentioned organic films. That is, the present invention provides a method for manufacturing a substrate for a semiconductor device, which involves forming an organic film on a substrate having an uneven pattern using the organic film formation method of the present invention described above, forming an inorganic hard mask selected from silicon oxide film, silicon nitride film, silicon oxynitride film, amorphous silicon film, and titanium nitride film on the organic film, forming a photoresist upper layer film on the inorganic hard mask using a photoresist composition, forming a circuit pattern on the photoresist upper layer film, using the photoresist upper layer film with the pattern formed thereon as a mask and transferring the pattern to the inorganic hard mask using dry etching, using the inorganic hard mask with the transferred pattern as a mask and transferring the pattern to the organic film using dry etching, and then using the organic film with the transferred pattern as a mask and transferring the pattern to the substrate using dry etching.

[0132] In addition, the inorganic hard mask is preferably formed by CVD or ALD.

[0133] The etching of the inorganic hard mask can be performed, for example, using a Freon-based gas to mask the resist pattern. Then, the inorganic hard mask pattern can be used as a mask to perform dry etching of the organic film using oxygen or hydrogen. Except for forming an inorganic hard mask on the organic film to replace the silicon-containing resist intermediate film, the process can be performed in the same manner as the aforementioned manufacturing method for a semiconductor device substrate using a silicon-containing resist intermediate film.

[0134] Alternatively, a multilayer resist film or organic antireflective film composed of an organic film and a silicon-containing resist intermediate film can also be formed on the inorganic hard mask. That is, the present invention provides a method for manufacturing a substrate for a semiconductor device, which involves forming an organic film on a substrate having a raised or recessed pattern using the above-described method for forming an organic film; forming an inorganic hard mask selected from silicon oxide film, silicon nitride film, silicon oxynitride film, amorphous silicon film, and titanium nitride film on the organic film; forming a multilayer resist film or organic antireflective film composed of an organic film and a silicon-containing resist intermediate film on the inorganic hard mask; and using a photoresist on the multilayer resist film or organic antireflective film. A resist upper layer film is formed, and a circuit pattern is formed on the resist upper layer film. The resist upper layer film with the pattern is used as a mask. The pattern is transferred to the aforementioned inorganic hard mask by dry etching through the pattern transfer of the aforementioned multilayer resist film or the aforementioned organic antireflective film. The inorganic hard mask with the transferred pattern is used as a mask, and the pattern is transferred to the organic film formed on the aforementioned substrate by dry etching. Then, the organic film with the transferred pattern is used as a mask, and the pattern is transferred to the aforementioned substrate by dry etching.

[0135] When using inorganic hard masks such as silicon oxide film, silicon oxynitride film, silicon oxynitride film, amorphous silicon film, or titanium oxynitride film, the combination of inorganic hard mask and BARC can suppress reflection even in immersion exposure with high NA exceeding 1.0. Another advantage of forming BARC is that it can achieve a wider process tolerance directly above the inorganic hard mask.

[0136] It should be noted that, apart from forming a multilayer resist film or organic antireflective film composed of an organic film and a silicon-containing resist intermediate film on an inorganic hard mask, this method can be carried out in the same way as the manufacturing method of a semiconductor device substrate using the above-mentioned inorganic hard mask.

[0137] As described above, since the organic film formed using the method of the present invention has excellent flatness characteristics, by combining this organic film with various film materials in multilayer resist technologies such as two-layer resist technology, three-layer resist technology using a silicon-containing resist intermediate film, or four-layer resist technology using a silicon-containing resist intermediate film and an organic anti-reflective film, the pattern of the upper photoresist (resist upper film) can be transferred to the substrate with high precision, thereby forming a pattern on the substrate. That is, if it is the semiconductor device substrate manufacturing method of the present invention, a high-precision semiconductor device substrate can be manufactured. [Example]

[0138] Hereinafter, synthetic examples, comparative synthetic examples, embodiments and comparative examples will be shown to describe the present invention in more detail, but the present invention is not limited thereto.

[0139] [Preparation of Organic Film Forming Compositions (UDL-1~6)] The organic film forming resins (B1)~(B6) and solvents (C-1) used in the preparation of the organic film forming compositions are as follows.

[0140] [Resin for forming organic films] B1: Resin shown in formula (B-1) below B2: Resin shown in formula (B-2) below B3: Resin shown in formula (B-3) below B4: Resin shown in formula (B-4) below B5: Resin shown in formula (B-5) below B6: Resin shown in formula (B-6) below

[0141] [Chemistry 39]

[0142] [Solvent] C-1: Propylene glycol monomethyl ether acetate (boiling point: 146℃)

[0143] Organic membrane forming resins (B1) to (B6) were dissolved in solvent (C-1) containing 0.5% by mass of FC-4430 (manufactured by Sumitomo 3M Co., Ltd.) in the proportions shown in Table 1, and filtered through a 0.1 μm fluorinated resin filter to prepare organic membrane materials (organic membrane forming compositions: UDL-1 to 6). It should be noted that the numbers in the table are parts by mass.

[0144] [Table 1] Organic film formation organic polymers solvent Composition (parts by weight) (parts by weight) UDL-1 B-1 10 C-1(100) UDL-2 B-2 10 C-1(100) UDL-3 B-3 10 C-1(100) UDL-4 B-4 10 C-1(100) UDL-5 B-5 10 C-1(100) UDL-6 B-6 10 C-1(100)

[0145] The following shows (A) coating solvents (A-1) to (A-5) and the organic solvent used in the comparative example (R-1). [Table 2] (A) Coating solvent Standard boiling point (°C) Compound Structure A-1 188 A-2 260 A-3 242 A-4 364 A-5 311 R-1 146

[0146] [Evaluation of solubility in organic solvents: Examples 1-1 to 1-9, Comparative Examples 1-1 to 1-2] The above-described organic film forming compositions (UDL-1 to 6) were coated onto a silicon substrate without a raised or recessed pattern. After firing under the baking conditions described in Table 3, the film thickness from the center to the outer periphery of the substrate was measured, and the average film thickness (a [nm]) was calculated. Next, the coating solvent (A) described in Table 3 was applied to the substrate, and the substrate was left to dry by rotation for 30 seconds. The coating solvent was then evaporated by baking at 100°C for 60 seconds, and the film thickness (b [nm]) was measured. The difference in film thickness before and after the coating solvent treatment was calculated (residual film rate: (b / a) × 100). [Table 3] Example Organic film formation Film thickness a Steps before insoluble treatment Film thicknessb Residual film rate Organic film formation Composition Baking temperature nm (A) Coating solvent nm (b / a)×100 Example 1-1 UDL-1 250℃ 80.2 A-1 79.7 99.4% Examples 1-2 UDL-2 220℃ 79.6 A-2 68.7 86.3% Examples 1-3 UDL-3 250℃ 77.8 A-3 70.3 90.4% Examples 1-4 UDL-4 250℃ 78.5 A-4 68.9 87.8% Examples 1-5 UDL-5 250℃ 79.4 A-5 74.2 93.5% Examples 1-6 UDL-6 250℃ 79.8 A-5 73.4 92.0% Examples 1-7 UDL-1 250℃ 80.2 A-5 70.5 87.9% Examples 1-8 UDL-1 270℃ 79.4 A-5 72.4 91.2% Examples 1-9 UDL-1 300℃ 78.8 A-5 74.3 94.3% Comparative Example 1-1 UDL-1 250℃ 80.2 R-1 75.4 94.0% Comparative Examples 1-2 UDL-1 350℃ 80.2 A-5 80.5 100.4%

[0147] As shown in Table 3, in Examples 1-1 to 1-9, after forming the coated film, a coating solvent with a standard boiling point of 160°C or higher and less than 500°C was spin-coated onto the coated film before the above-mentioned insolubility treatment. It was observed that the film thickness decreased after the insolubility treatment, and a portion of the coated film dissolved in the respective coating solvents. On the other hand, in Comparative Examples 1-2, almost no change in film thickness was observed before and after applying the coating solvent. This indicates that the resin in the coated film (the organic polymer (B-1) in UDL-1) is insoluble in the coating solvent (A-5). In this comparative example, the film thickness after applying the coating solvent was slightly thicker than the film thickness before applying the coating solvent, presumably because baking was not performed at a temperature sufficiently high relative to the boiling point of the coating solvent, thus leaving the coating solvent in the coated film and causing it to thicken.

[0148] [Evaluation of Planarization Characteristics: Examples 2-1 to 2-10, Comparative Examples 2-1 to 2-8] [Pattern A] The above-mentioned organic film forming compositions (UDL-1 to 6) were coated onto a substrate 5 (SiO2 wafer substrate) with a large isolated trench pattern (Fig. 3(A), trench width 10 μm, trench depth 0.10 μm). After firing (baking) under the conditions described in Table 4, each coating liquid was coated onto the organic film using spin coating. After treatment using the insoluble treatment method described in Table 4, the height difference of the insoluble coating film (organic film) 6 in the trench portion and the non-trench portion was observed using an NX10 atomic force microscope (AFM) manufactured by Park Systems (delta7 in Fig. 3(B)). The results are shown in Table 4. In this evaluation (flatness A), the smaller the height difference, the better the flatness characteristics. Furthermore, in this evaluation, an organic film with a typical thickness of about 0.2 μm was formed using an organic film forming composition to planarize a groove pattern with a depth of 0.10 μm. In order to evaluate the quality of the planarization characteristics, this became a special and rigorous evaluation condition.

[0149] [Pattern B] The above-mentioned organic film forming compositions (UDL-1~6) were respectively coated onto a substrate 8 (SiO2 wafer substrate) having a dense line and spacing pattern (Fig. 4(A), line width 60nm, line depth 100nm, distance between the centers of two adjacent lines 120nm). After firing under the conditions described in Table 4, each coating liquid was coated onto the organic film using spin coating. After treatment using the insoluble treatment method described in Table 4, the cross-sectional shape of each wafer substrate was observed using a scanning electron microscope (SEM). The height difference Delta 10 of the insoluble coating film (filling film) 9 between the dense line pattern area and the non-line pattern area was observed using a microscope (S-4700) manufactured by Hitachi, Ltd. The results are shown in Table 4. In this evaluation (flatness B), it can be said that the smaller the height difference, the better the flattening characteristics.

[0150] <Additional Processing Conditions (Plasma Processing)> Plasma processing was performed under the following conditions using the Telius etching apparatus manufactured by Tokyo Powertech. Plasma Processing Conditions: Chamber Pressure: 100 mT; RF Power (Top): 100 W; RF Power (Bottom): 3500 W; H2 Gas Flow Rate: 200 sccm; Time: 20 sec

[0151] [Table 4] Example Organic film formation Steps before insoluble treatment Insoluble treatment Flatness A Flatness B Organic film formation Composition Baking temperature (A) Coating solvent Method (1) nm nm Example 2-1 UDL-1 250℃ A-1 350℃ 95 35 Example 2-2 UDL-2 220℃ A-2 350℃ 100 35 Example 2-3 UDL-3 250℃ A-3 350℃ 70 30 Examples 2-4 UDL-4 250℃ A-4 350℃ 75 32 Examples 2-5 UDL-5 250℃ A-5 350℃ 85 34 Examples 2-6 UDL-6 250℃ A-5 350℃ 85 35 Examples 2-7 UDL-1 250℃ A-5 350℃ 80 31 Examples 2-8 UDL-1 270℃ A-5 350℃ 75 29 Examples 2-9 UDL-1 300℃ A-5 350℃ 80 30 Example 2-10 UDL-1 270℃ A-5 Plasma treatment 80 31 Comparative Example 2-1 UDL-1 350℃ none - 110 40 Comparative Example 2-2 UDL-1 250℃ R-1 350℃ 105 39 Comparative Examples 2-3 UDL-1 350℃ A-5 350℃ 110 40 Comparative Examples 2-4 UDL-2 350℃ none - 120 39 Comparative Examples 2-5 UDL-3 350℃ none - 90 34 Comparative Examples 2-6 UDL-4 350℃ none - 95 36 Comparative Examples 2-7 UDL-5 350℃ none - 105 38 Comparative Examples 2-8 UDL-6 350℃ none - 105 39

[0152] As shown in Table 4, Examples 2-1 to 2-10 using the organic film formation method of the present invention exhibited superior planarization characteristics in both Pattern A and Pattern B compared to Comparative Examples 2-1 and 2-4 to 2-8, which use conventional organic film formation methods (excluding the step of spin-coating a coating solvent with a standard boiling point of 160°C or higher and less than 500°C onto the coating film before insolubilization treatment). Examples 2-4, 2-5, and 2-7 to 2-9, which use aromatic compounds (A-4) and (A-5) containing benzyl or benzoyl groups in the coating solvent, exhibited superior planarization characteristics. On the other hand, the organic film formation method (Comparative Example 2-2) that includes the step of spin-coating an organic solvent with a boiling point less than 160°C onto the coating film did not show ideal improvement in planarization compared to the previous organic film formation method. Furthermore, in the solvent resistance evaluation of Example 1, no change in film thickness was observed before and after solvent coating in the organic film formation method (Comparative Examples 2-3). Since the coating solvent could not dissolve the coating film, it could not impart sufficient thermal fluidity to the resin components in the uncured coating film. Therefore, no improvement in flatness was observed compared to the previous organic film formation method.

[0153] In the organic film formation method of the present invention, the coating film before the aforementioned insoluble treatment is dissolved relative to the aforementioned coating solvent, and the resin component in the uncured coating film can obtain sufficient thermal fluidity. Therefore, it is believed that an inhibitor lower layer film with excellent filling / planarization characteristics can be formed. Therefore, the coating film before the insoluble treatment is preferably dissolved relative to the aforementioned coating solvent. According to the results of Examples 1 and 2, when the film thickness of the coating film before the insoluble treatment formed by spin coating using the composition for forming organic films is set as a, and the film thickness of the organic film formed by spin coating the aforementioned coating solvent onto the coating film and then performing a heat treatment at 100°C for 60 seconds is set as b, the ratio of b / a is preferably 99.5% or less.

[0154] This specification includes the following methods. [1]: An organic film forming method, which is a method of forming an organic film on a substrate having a raised or recessed pattern, characterized by including the following steps: a step of spin-coating an organic film forming composition onto the substrate to form a coating film; a step of spin-coating a coating solvent capable of dissolving the coating film with a standard boiling point of 160°C or higher and less than 500°C onto the coating film; and a step of forming an organic film by performing an insoluble treatment on the coating film relative to the coating solvent. [2]: The organic film forming method of [1], wherein, as the insoluble treatment, any one or a combination thereof is used, such as heat treatment at 100°C or higher and 600°C or lower, ultraviolet irradiation treatment with a wavelength of 400 nm or lower, electron beam irradiation treatment, and plasma irradiation treatment. [3]: The organic film forming method of [1] or [2], wherein, as the coating solvent, an alcohol, an ester, a ketone, a carbonate, an ether, or a combination thereof is used. [4]: An organic film forming method of any one of [1] to [3], wherein an aromatic compound having a benzyl or benzoyl group is used as the coating solvent. [5]: An organic film forming method of any one of [1] to [4], wherein a composition comprising a resin having one or more aromatic rings is used as the composition for forming the organic film. [6]: A method for manufacturing a substrate for a semiconductor device, characterized in that an organic film is formed on a substrate having a raised or recessed pattern using an organic film forming method as described in any one of [1] to [5], a silicon-containing resist intermediate film is formed on the organic film using a silicon-containing resist intermediate film forming composition, a resist upper layer film is formed on the silicon-containing resist intermediate film using a photoresist composition, a circuit pattern is formed on the resist upper layer film, the resist upper layer film with the pattern is used as a mask, the pattern is transferred to the silicon-containing resist intermediate film by dry etching, the silicon-containing resist intermediate film with the transferred pattern is used as a mask, the pattern is transferred to the organic film by dry etching, and then the organic film with the transferred pattern is used as a mask, the pattern is transferred to the substrate by dry etching. [7]: A method for manufacturing a substrate for a semiconductor device, characterized in that an organic film is formed on a substrate having a raised or recessed pattern using an organic film forming method as described in any one of [1] to [5], a silicon-containing resist intermediate film is formed on the organic film using a silicon-containing resist intermediate film forming composition, an organic anti-reflective film is formed on the silicon-containing resist intermediate film, a resist upper film is formed on the organic anti-reflective film using a photoresist composition to form a resist upper film, and four resist films are formed, a circuit pattern is formed on the resist upper film, the resist upper film with the pattern is used as a mask, the pattern is transferred to the organic anti-reflective film and the silicon-containing resist intermediate film by dry etching, the organic anti-reflective film with the transferred pattern and the silicon-containing resist intermediate film are used as a mask, the pattern is transferred to the organic film by dry etching, and then the organic film with the transferred pattern is used as a mask, the pattern is transferred to the substrate by dry etching.[8]: A method for manufacturing a substrate for a semiconductor device, characterized in that an organic film is formed on a substrate having a raised or recessed pattern using an organic film forming method as described in any one of [1] to [5], an inorganic hard mask selected from silicon oxide film, silicon nitride film, silicon oxynitride film, amorphous silicon film, and titanium nitride film is formed on the organic film, a photoresist composition is used to form a photoresist top layer film on the inorganic hard mask, a circuit pattern is formed on the photoresist top layer film, the photoresist top layer film with the pattern is used as a mask, the pattern is transferred to the inorganic hard mask by dry etching, the inorganic hard mask with the transferred pattern is used as a mask, the pattern is transferred to the organic film by dry etching, and then the organic film with the transferred pattern is used as a mask, the pattern is transferred to the substrate by dry etching. [9]: A method for manufacturing a substrate for a semiconductor device, characterized in that an organic film is formed on a substrate having a raised or recessed pattern using an organic film forming method as described in any one of [1] to [5], an inorganic hard mask selected from silicon oxide film, silicon nitride film, silicon oxynitride film, amorphous silicon film, and titanium nitride film is formed on the organic film, a multilayer resist film or organic antireflective film composed of an organic film and a silicon-containing resist intermediate film is formed on the inorganic hard mask, and an organic antireflective film is formed on the multilayer resist film or organic antireflective film. A photoresist composition is used to form a photoresist top film, and a circuit pattern is formed on the photoresist top film. The photoresist top film with the pattern is used as a mask. The pattern is transferred to the inorganic hard mask by dry etching through pattern transfer of the multilayer photoresist film or the organic antireflective film. The inorganic hard mask with the transferred pattern is used as a mask. The pattern is transferred to the organic film formed on the substrate by dry etching. Then the organic film with the transferred pattern is used as a mask. The pattern is transferred to the substrate by dry etching.

[10] : A method for manufacturing a semiconductor device substrate as in [8] or [9], wherein the inorganic hard mask is formed by CVD or ALD.

[11] : A method for manufacturing a substrate for a semiconductor device according to any one of [6] to

[10] , wherein, in forming the circuit pattern, the circuit pattern is formed by any one or a combination of lithography based on high-energy rays with wavelengths of 10 nm or more and 300 nm or less, direct drawing based on electron beams, and nanoimprinting.

[12] : A method for manufacturing a substrate for a semiconductor device according to any one of [6] to

[11] , wherein, in forming the circuit pattern, the circuit pattern is developed using alkaline development or development using an organic solvent.

[0155] It should be noted that the present invention is not limited to the above embodiments. The above embodiments are illustrative examples, and those having a structure that is substantially the same as the technical concept described in the claims of the present invention and performing the same effects are all included in the technical scope of the present invention. [Simplified Explanation of the Diagram]

[0027] Figures 1(A) to (D) are flowcharts illustrating an example of forming an organic film on a substrate having a trench pattern using the organic film formation method of the present invention. Figures 2(A) to (D) are flowcharts illustrating an example of forming an organic film on a substrate having a line pattern using the organic film formation method of the present invention. Figures 3(A) and (B) are explanatory diagrams illustrating the planarization characteristics method of the trench pattern (pattern A) of the present invention. Figures 4(A) and (B) are explanatory diagrams illustrating the planarization characteristics method of the line pattern (pattern B) of the present invention.

Claims

1. An organic film forming method, comprising the steps of: spin-coating an organic film forming composition onto the substrate to form a coating film; spin-coating a coating solvent having a standard boiling point of 160°C or higher and less than 500°C onto the coating film; and forming an organic film by subjecting the coating film to an insoluble treatment relative to the coating solvent; wherein the organic film forming method uses an aromatic compound having a benzyl or benzoyl group as the coating solvent.

2. The method for forming an organic film as described in claim 1, wherein, As the insoluble treatment, any one or a combination thereof is used, such as heat treatment at 100°C or 600°C, ultraviolet irradiation treatment with a wavelength of 400 nm or less, electron beam irradiation treatment, and plasma irradiation treatment.

3. The method for forming an organic film as described in claim 1, wherein, Alcohols, esters, ketones, carbonates, ethers, or combinations thereof can be used as the coating solvent.

4. The method for forming an organic film as described in claim 1, wherein, As a component for forming the organic film, a composition containing a resin having one or more aromatic rings is used.

5. A method for manufacturing a substrate for a semiconductor device, characterized in that an organic film is formed on a substrate having a raised or recessed pattern using an organic film forming method as described in claim 1; a silicon-containing resist intermediate film is formed on the organic film using a silicon-containing resist intermediate film forming composition; a resist upper layer film is formed on the silicon-containing resist intermediate film using a photoresist composition; a circuit pattern is formed on the resist upper layer film; the resist upper layer film with the pattern is used as a mask; the pattern is transferred to the silicon-containing resist intermediate film using dry etching; the silicon-containing resist intermediate film with the transferred pattern is used as a mask; the pattern is transferred to the organic film using dry etching; and the organic film with the transferred pattern is used as a mask; the pattern is transferred to the substrate using dry etching.

6. A method for manufacturing a substrate for a semiconductor device, characterized in that an organic film is formed on a substrate having a raised or recessed pattern using an organic film forming method as described in claim 1; a silicon-containing resist intermediate film is formed on the organic film using a silicon-containing resist intermediate film forming composition; an organic antireflective film is formed on the silicon-containing resist intermediate film; a resist upper film is formed on the organic antireflective film using a photoresist composition to form a resist upper film, thereby forming four resist films; a circuit pattern is formed on the resist upper film; the resist upper film with the pattern is used as a mask; the pattern is transferred to the organic antireflective film and the silicon-containing resist intermediate film using dry etching; the organic antireflective film with the transferred pattern and the silicon-containing resist intermediate film are used as masks; the pattern is transferred to the organic film using dry etching; and the organic film with the transferred pattern is used as a mask; the pattern is transferred to the substrate using dry etching.

7. A method for manufacturing a substrate for a semiconductor device, characterized in that an organic film is formed on a substrate having a raised or recessed pattern using an organic film forming method as described in claim 1; an inorganic hard mask selected from silicon oxide film, silicon nitride film, silicon oxynitride film, amorphous silicon film, and titanium nitride film is formed on the organic film; a photoresist composition is used to form a photoresist top layer film on the inorganic hard mask; a circuit pattern is formed on the photoresist top layer film; the photoresist top layer film with the pattern is used as a mask; the pattern is transferred to the inorganic hard mask by dry etching; the inorganic hard mask with the transferred pattern is used as a mask; the pattern is transferred to the organic film by dry etching; and the organic film with the transferred pattern is used as a mask; the pattern is transferred to the substrate by dry etching.

8. A method for manufacturing a substrate for a semiconductor device, characterized in that, An organic film is formed on a substrate with an embossed pattern using the organic film formation method of claim 1. An inorganic hard mask selected from silicon oxide film, silicon nitride film, silicon oxynitride film, amorphous silicon film, and titanium nitride film is formed on the organic film. A multilayer resist film or organic antireflective film composed of an organic film and a silicon resist intermediate film is formed on the inorganic hard mask. A resist top layer film is formed on the multilayer resist film or organic antireflective film using a photoresist composition. A circuit pattern is formed on the resist top layer film. The resist top layer film with the pattern is used as a mask. The pattern is transferred to the inorganic hard mask by dry etching after transferring the pattern to the multilayer resist film or organic antireflective film. The inorganic hard mask with the transferred pattern is used as a mask. The pattern is transferred to the organic film formed on the substrate by dry etching. The organic film with the transferred pattern is used as a mask. The pattern is transferred to the substrate by dry etching.

9. A method for manufacturing a substrate for a semiconductor device as described in claim 7 or 8, wherein, The inorganic hard mask is formed using CVD or ALD methods.

10. A method for manufacturing a substrate for a semiconductor device as described in any one of claims 5 to 8, wherein, In the formation of this circuit pattern, the circuit pattern is formed by any one or a combination of high-energy rays with wavelengths above 10 nm and below 300 nm, direct drawing based on electron beams, and nanoimprinting.

11. A method for manufacturing a substrate for a semiconductor device as described in any of claims 5 to 8, wherein, In the formation of this circuit pattern, the circuit pattern is developed using alkaline development or development using organic solvents.

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