Lower layer film formation composition of inhibitor

Abstract

The present invention relates to a resist underlayer film forming composition that improves the filling property of the pattern during firing by improving the thermal reflowability of the polymer, a resist underlayer film as a fired product of a coating film formed from the resist underlayer film forming composition, and a method for manufacturing a semiconductor device including the step of forming the resist underlayer film. The inhibitor lower film forming composition of the present invention contains a compound of formula (A) or formula (B) and a solvent.

Description

Technical Field

[0001] The present invention relates to a resist underlayer film forming composition for forming a planarization film on a substrate having a step difference, and a method for manufacturing a laminated substrate planarized using the resist underlayer film. Prior Technology

[0002] In the past, semiconductor device manufacturing relied on photolithography using photoresist compositions for microfabrication. This microfabrication involved forming a thin film of photoresist composition on a substrate such as a silicon wafer, irradiating it with an active light source such as ultraviolet light using a photomask pattern depicting a semiconductor device, developing the image, and then using the resulting photoresist pattern as a protective film to etch the substrate. However, in recent years, with the increasing integration of semiconductor devices, the active light source used has shortened from KrF excimer lasers (248nm) to ArF excimer lasers (193nm). Therefore, irregular reflections or standing waves from the substrate due to the active light source have become a significant problem, leading to the widespread use of anti-reflection films between the photoresist and the substrate. Furthermore, with the aim of further microfabrication, development is underway for photolithography techniques using extreme ultraviolet light (EUV, 13.5nm) or electron beam (EB) light. Although specific anti-reflection films are not necessary in EUV or EB lithography because they do not produce irregular reflections or standing waves that are common to substrates, the underlayer resist film has begun to be widely reviewed as an auxiliary film for improving the resolution or adhesion of resist patterns.

[0003] On the other hand, as exposure wavelengths shorten, the depth of focus decreases. Therefore, to achieve the desired resist pattern with higher precision, improving the planarity of the film formed on the substrate becomes more important. In other words, when manufacturing semiconductor devices with fine design rules, a resist underlayer film that can be flatly coated on the substrate without steps becomes an indispensable necessity.

[0004] For example, a resistive underlayer film forming composition containing a crosslinking compound having 2 to 10 carbon atoms of alkoxymethyl and 1 to 10 carbon atoms of alkyl has been disclosed (see Patent Document 1). By using this composition, good embedding properties are exhibited when coating a substrate with a hole pattern.

[0005] Furthermore, a resistive lower film formation composition containing phenolic varnish resin using phenylnaphthylamine has been disclosed. (See Patent Document 2)

[0006] Then, it has been disclosed that a lower film forming composition containing a polymer that reacts with a phenolic varnish resin using phenylnaphthylamine and t-butoxystyrene has been used as an inhibitor. (Refer to Patent Document 3) [Previous Technical Documents] [Patent Literature]

[0007] [Patent Document 1] International Publication No. WO2014 / 208542 [Patent Document 2] International Publication No. WO2013 / 047516 [Patent Document 3] International Publication No. WO2015 / 151803 Summary of the Invention

[0008] [The problem solved by the invention]

[0009] When the photoresist underlayer forming composition avoids mixing during the lamination of photoresist compositions or dissimilar photoresist underlayers, the coating film can be thermosetting by introducing the polymer resin, which is the main component, into its own crosslinking sites, or by adding appropriate crosslinking agents, crosslinking catalysts, etc., and then firing (baking) at high temperature. This allows lamination to be performed without mixing photoresist compositions or dissimilar photoresist underlayers. However, such thermosetting photoresist underlayer forming compositions contain polymers with thermocrosslinking functional groups such as hydroxyl groups, crosslinking agents, and acid catalysts (acid generators). When these compositions fill patterns (e.g., holes or trench structures) formed on a substrate, the viscosity increases due to the crosslinking reaction during firing, which deteriorates the pattern filling ability and makes the planarization of the film after deposition easier to reduce. The present invention aims to improve the filling of the pattern during firing and improve the planarization of the underlayer film of the thermosetting inhibitor by enhancing the thermal reflow properties of the composition. However, the present invention provides a resistive underlayer film forming composition for use in forming a resistive underlayer film that also has heat resistance. [Methods for solving the problem]

[0010] That is, as a first aspect of the present invention, it relates to a resistive lower film forming composition containing compounds and solvents as shown in formula (A) and / or formula (B). In formula (A), Ar1 and Ar2 each represent independently a group consisting of one or more aromatic rings with 6 to 30 carbon atoms that can be substituted via Z1; R1 represents a hydrogen atom, an alkyl group with 1 to 10 carbon atoms, an alkenyl group with 2 to 10 carbon atoms, or an alkynyl group with 2 to 10 carbon atoms; X represents a single bond or an oxygen atom; Ar7 represents the same group as Ar1 and Ar2 when X is a single bond, and represents a phenyl or naphthyl group when X is an oxygen atom. In equation (B), Ar3~Ar6 are defined the same as Ar1 and Ar2 as described above, R2 and R3 are defined the same as described above, Y represents a single bond or a divalent group that can be substituted by Z2, n1, n2, m1, and m2 represent 0 or 1, and all of n1, n2, m1, and m2 cannot be 0 at the same time. Z1 is selected from at least one group consisting of halogen atoms, hydroxyl groups, cyano groups, methylamino groups, methyl ether groups, cyclic alkyl groups, phenyl groups, pyridyl groups, alkyl groups with 1 to 10 carbon atoms, alkenyl groups with 2 to 10 carbon atoms, and alkynyl groups with 2 to 10 carbon atoms. Z2 is selected from at least one alkyl group having 1 to 10 carbon atoms and a fluoroalkyl group having 1 to 10 carbon atoms. As a second aspect of the present invention, the first aspect describes a resistive lower film forming composition in which Ar1 to Ar6 in the aforementioned formula (A) or formula (B) are each independently composed of a base consisting of one or more aromatic rings containing a benzene ring. As a third aspect of the present invention, it relates to the inhibitor lower film forming composition described in the first or second aspect of the aforementioned formula (A), where R1 represents a hydrogen atom or an alkynyl group having 2 to 10 carbon atoms. As a fourth aspect of the present invention, it refers to the resistive underlayer film forming composition described in any one of the first to third aspects of the present invention, where Ar3 to Ar6 in the aforementioned formula (B) are of the same base. As the fifth aspect of the present invention, the inhibitor lower film forming composition described in any one of the first to fourth aspects regarding the divalent group in the aforementioned formula (B) being selected from the group consisting of branches or straight chains of alkyl, phenyl, naphthyl, anthracene, sulfonyl, carbonyl, ether, and thioether groups having 1 to 15 carbon atoms, or groups formed by combinations thereof. As the sixth aspect of the present invention, the inhibitor underlayer film forming composition described in the fifth aspect, where the divalent group in the aforementioned formula (B) is any of the groups shown below. (* indicates the bond position of the aromatic ring) As the seventh aspect of the present invention, it relates to the inhibitor lower film forming composition described in any one of the first to sixth aspects of the aforementioned formula (B), wherein R2 and / or R3 are hydrogen atoms or alkynyl groups having 2 to 10 carbon atoms. As the eighth aspect of the present invention, it relates to the inhibitory underlayer film forming composition described in any one of the first to seventh aspects that further contain a crosslinking agent. As the ninth aspect of the present invention, it relates to the inhibitor lower film forming composition described in any one of the first to eighth aspects that further contain acid and / or acid generating agents. As the tenth aspect of the present invention, it refers to the inhibitor lower layer film forming composition described in any one of the first to ninth aspects regarding the solvent being a solvent with a boiling point of 160°C or higher. As the eleventh aspect of the present invention, it is characterized by a fired product of a coating film formed from a resistive underlayer film forming composition as described in any one of the first to tenth aspects. As the 12th aspect of the present invention, it relates to a method for manufacturing a semiconductor device comprising: forming a resist underlayer film on a semiconductor substrate by means of a resist underlayer film forming composition described in any one of the 1st to 10th aspects; forming a resist film on the substrate; forming a resist pattern by means of irradiation and development by light or electron beams; etching the resist underlayer film by means of the resist pattern; and processing a semiconductor substrate by means of the patterned resist underlayer film. [Effects of the Invention]

[0011] The resist underlayer film composition of the present invention not only has high etch resistance, good dry etch rate ratio and optical constant, but the resulting resist underlayer film also has good coverage for so-called stepped substrates, and the thickness difference of the film after embedding is reduced, forming a flat film, thus achieving finer substrate processing. In particular, the resist underlayer film of the present invention forms at least two layers of resist underlayer film with the aim of thinning the resist film thickness, which is effective for photolithography processing using the resist underlayer film as an etching mask. Simple Explanation of the Diagram

[0012] [Figure 1] Figure 1 shows a cross-sectional SEM image of the results of a coating test on a stepped substrate using a composition formed by a resist lower film modified in Comparative Example 1. The left image shows the densely patterned area, and the right image shows the open area. [Figure 2] Figure 2 shows a cross-sectional SEM image of the results of a coating test on a stepped substrate using the resist underlayer film composition prepared in Example 2. The left image shows the densely patterned area, and the right image shows the open area. Implementation

[0013] [Types of Invention Implementation] [Inhibitor Lower Layer Film Formation Composition]

[0014] The inhibitor lower film forming composition of the present invention contains a compound of formula (A) and / or formula (B) and a solvent. In formula (A), Ar1 and Ar2 each represent independently a group consisting of one or more aromatic rings with 6 to 30 carbon atoms that can be substituted via Z1; R1 represents a hydrogen atom, an alkyl group with 1 to 10 carbon atoms, an alkenyl group with 2 to 10 carbon atoms, or an alkynyl group with 2 to 10 carbon atoms; X represents a single bond or an oxygen atom; Ar7 represents the same group as Ar1 and Ar2 when X is a single bond, and represents a phenyl or naphthyl group when X is an oxygen atom. In equation (B), Ar3~Ar6 are defined the same as Ar1 and Ar2 as described above, R2 and R3 are defined the same as described above, Y represents a single bond or a divalent group that can be substituted by Z2, n1, n2, m1, and m2 represent 0 or 1, and all of n1, n2, m1, and m2 cannot be 0 at the same time. Z1 is selected from at least one group consisting of halogen atoms, hydroxyl groups, cyano groups, methylamino groups, methyl ether groups, cyclic alkyl groups, phenyl groups, pyridyl groups, alkyl groups with 1 to 10 carbon atoms, alkenyl groups with 2 to 10 carbon atoms, and alkynyl groups with 2 to 10 carbon atoms. Z2 is selected from at least one alkyl group having 1 to 10 carbon atoms and a fluoroalkyl group having 1 to 10 carbon atoms.

[0015] [The compound shown in formula (A)] In formula (A), Ar1 and Ar2 are each represented independently, and are composed of one or more aromatic rings with 6 to 30 carbon atoms that can be substituted by Z1.

[0016] Substituent Z1 is selected from at least one group consisting of a halogen atom, hydroxyl group, cyano group, methylamino group, methyl ether group, cyclic alkyl group, phenyl group, pyridyl group, alkyl group with 1 to 10 carbon atoms, alkenyl group with 2 to 10 carbon atoms, and alkynyl group with 2 to 10 carbon atoms.

[0017] Specific examples of cyclic alkyl groups include cyclopropyl, cyclobutyl, 1-methyl-cyclopropyl, 2-methyl-cyclopropyl, cyclopentyl, 1-methyl-cyclobutyl, 2-methyl-cyclobutyl, 3-methyl-cyclobutyl, 1,2-dimethyl-cyclopropyl, 2,3-dimethyl-cyclopropyl, 1-ethyl-cyclopropyl, 2-ethyl-cyclopropyl, cyclohexyl, 1-methyl-cyclopentyl, 2-methyl-cyclopentyl, 3-methyl-cyclopentyl, 1-ethyl-cyclobutyl, 2-ethyl-cyclobutyl, 3-ethyl-cyclobutyl, 1,2-dimethyl-cyclobutyl, 1,3-dimethyl-cyclobutyl, 2,2-dimethyl-cyclobutyl, 2,3-dimethyl-cyclobutyl. Cycloalkyl groups such as 2,4-dimethyl-cyclobutyl, 3,3-dimethyl-cyclobutyl, 1-n-propyl-cyclopropyl, 2-n-propyl-cyclopropyl, 1-i-propyl-cyclopropyl, 2-i-propyl-cyclopropyl, 1,2,2-trimethyl-cyclopropyl, 1,2,3-trimethyl-cyclopropyl, 2,2,3-trimethyl-cyclopropyl, 1-ethyl-2-methyl-cyclopropyl, 2-ethyl-1-methyl-cyclopropyl, 2-ethyl-2-methyl-cyclopropyl, 2-ethyl-3-methyl-cyclopropyl, as well as cycloalkyl groups such as bicyclobutyl, bicyclopentyl, bicyclohexyl, bicycloheptyl, bicyclooctyl, bicyclononyl, and bicyclodecyl, but not limited to these.

[0018] For the description of alkyl groups with 1 to 10 carbon atoms, alkenyl groups with 2 to 10 carbon atoms, and alkynyl groups with 2 to 10 carbon atoms, please refer to the description of R 1 below.

[0019] As a group composed of one or more aromatic rings with 6 to 30 carbon atoms that can be substituted by Z-1, the aromatic ring that can be substituted by Z-1 can be a single ring or a plurality of benzene rings, naphthalene rings, or quinoline rings bonded together with carbon atoms, with the presence of a benzene ring being preferred. When multiple aromatic rings exist, the aromatic rings can also be bonded together with single bonds. Examples of such combinations of aromatic rings are shown below, but are not limited to these.

[0020] (* indicates the bonding position with the benzene ring)

[0021] In formula (A), R1 represents a hydrogen atom, an alkyl group with 1 to 10 carbon atoms, an alkenyl group with 2 to 10 carbon atoms, or an alkynyl group with 2 to 10 carbon atoms. Examples of alkyl groups having 1 to 10 carbon atoms include methyl, ethyl, n-propyl, i-propyl, cyclopropyl, n-butyl, i-butyl, s-butyl, t-butyl, cyclobutyl, 1-methyl-cyclopropyl, 2-methyl-cyclopropyl, n-pentyl, 1-methyl-n-butyl, 2-methyl-n-butyl, 3-methyl-n-butyl, 1,1-dimethyl-n-propyl, 1,2-dimethyl-n-propyl, 2,2-dimethyl-n-propyl, 1-ethyl-n-propyl, cyclopentyl, 1-methyl-cyclobutyl, 2- Methyl-cyclobutyl, 3-methyl-cyclobutyl, 1,2-dimethyl-cyclopropyl, 2,3-dimethyl-cyclopropyl, 1-ethyl-cyclopropyl, 2-ethyl-cyclopropyl, n-hexyl, 1-methyl-n-pentyl, 2-methyl-n-pentyl, 3-methyl-n-pentyl, 4-methyl-n-pentyl, 1,1-dimethyl-n-butyl, 1,2-dimethyl-n-butyl, 1,3-dimethyl-n-butyl, 2,2-dimethyl-n-butyl, 2,3-dimethyl-n-butyl, 3,3-dimethyl-n- Butyl, 1-ethyl-n-butyl, 2-ethyl-n-butyl, 1,1,2-trimethyl-n-propyl, 1,2,2-trimethyl-n-propyl, 1-ethyl-1-methyl-n-propyl, 1-ethyl-2-methyl-n-propyl, cyclohexyl, 1-methyl-cyclopentyl, 2-methyl-cyclopentyl, 3-methyl-cyclopentyl, 1-ethyl-cyclobutyl, 2-ethyl-cyclobutyl, 3-ethyl-cyclobutyl, 1,2-dimethyl-cyclobutyl, 1,3-dimethyl-cyclobutyl, 2,2-dimethyl-cyclobutyl, 2 3-Dimethyl-cyclobutyl, 2,4-Dimethyl-cyclobutyl, 3,3-Dimethyl-cyclobutyl, 1-n-propyl-cyclopropyl, 2-n-propyl-cyclopropyl, 1-i-propyl-cyclopropyl, 2-i-propyl-cyclopropyl, 1,2,2-trimethyl-cyclopropyl, 1,2,3-trimethyl-cyclopropyl, 2,2,3-trimethyl-cyclopropyl, 1-ethyl-2-methyl-cyclopropyl, 2-ethyl-1-methyl-cyclopropyl, 2-ethyl-2-methyl-cyclopropyl, and 2-ethyl-3-methyl-cyclopropyl, etc. These alkyl groups can also be interrupted by an oxygen atom, a carbonyl group, or a carboxyl group. Among these, alkyl groups with 3 or fewer carbon atoms are preferred.

[0022] Examples of alkenyl groups with 2 to 10 carbon atoms include vinyl, 1-propenyl, 2-propenyl, 1-methyl-1-vinyl, 1-butenyl, 2-butenyl, 3-butenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl, 1-ethylvinyl, 1-methyl-1-propenyl, 1-methyl-2-propenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-n-propylvinyl, 1-methyl-1-butenyl, 1-methyl-2-butenyl, 1-methyl-3-butenyl, 2-ethyl-2-propenyl, 2-methyl-1-butenyl, 2-methyl-2-butenyl, and 2-methyl-3-butenyl. 3-Methyl-1-butenyl, 3-methyl-2-butenyl, 3-methyl-3-butenyl, 1,1-dimethyl-2-propenyl, 1-i-propylvinyl, 1,2-dimethyl-1-propenyl, 1,2-dimethyl-2-propenyl, 1-cyclopentenyl, 2-cyclopentenyl, 3-cyclopentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl, 1-methyl-1-pentenyl, 1-methyl-2-pentenyl, 1-methyl-3-pentenyl, 1-methyl-4-pentenyl, 1-n-butylvinyl, 2-methyl-1-pentenyl, 2-methyl-2-pentenyl, 2-methyl-3-pentenyl, 2 -Methyl-4-pentenyl, 2-n-propyl-2-propenyl, 3-methyl-1-pentenyl, 3-methyl-2-pentenyl, 3-methyl-3-pentenyl, 3-methyl-4-pentenyl, 3-ethyl-3-butenyl, 4-methyl-1-pentenyl, 4-methyl-2-pentenyl, 4-methyl-3-pentenyl, 4-methyl-4-pentenyl, 1,1-dimethyl-2-butenyl, 1,1-dimethyl-3-butenyl, 1,2-dimethyl-1-butenyl, 1,2-dimethyl-2-butenyl, 1,2-dimethyl-3-butenyl, 1-methyl-2-ethyl-2-propenyl, 1-s-butylvinyl, 1,3-dimethyl 1,3-Dimethyl-2-butenyl, 1,3-Dimethyl-3-butenyl, 1-i-Butylvinyl, 2,2-Dimethyl-3-butenyl, 2,3-Dimethyl-1-butenyl, 2,3-Dimethyl-2-butenyl, 2,3-Dimethyl-3-butenyl, 2-i-Propyl-2-propenyl, 3,3-Dimethyl-1-butenyl, 1-Ethyl-1-butenyl, 1-Ethyl-2-butenyl, 1-Ethyl-3-butenyl, 1-n-Propyl-1-propenyl, 1-n-Propyl-2-propenyl, 2-Ethyl-1-butenyl, 2-Ethyl-2-butenyl, 2-Ethyl-3-butenyl, 1,1,2-Trimethyl-2-propenyl, 1-t-Butylvinyl, 1-Methyl-1-ethyl-2-propenyl, 1-Ethyl-2-methyl-1-propenyl, 1-Ethyl-2-methyl-2-propenyl, 1-I-propyl-1-propenyl, 1-I-propyl-2-propenyl, 1-Methyl-2-cyclopentenyl, 1-Methyl-3-cyclopentenyl, 2-Methyl-1-cyclopentenyl, 2-Methyl-2-cyclopentenyl Alkenyl, 2-methyl-3-cyclopentenyl, 2-methyl-4-cyclopentenyl, 2-methyl-5-cyclopentenyl, 2-methylene-cyclopentyl, 3-methyl-1-cyclopentenyl, 3-methyl-2-cyclopentenyl, 3-methyl-3-cyclopentenyl, 3-methyl-4-cyclopentenyl, 3-methyl-5-cyclopentenyl, 3-methylene-cyclopentenyl, 1-cyclohexenyl, 2-cyclohexenyl, and 3-cyclohexenyl, etc. These alkenyl groups can also be interrupted by oxygen atoms, carbonyl groups, or carboxyl groups. Among these, alkenyl groups with 5 or fewer carbon atoms are preferred.

[0023] Examples of alkyne groups having 2 to 10 carbon atoms include ethynyl, 1-propynyl, 1-butynyl, 1-pentynyl, 1-hexynyl, 1-methyl-3-pentynyl, 1-methyl-3-hexynyl, 2-methyl-3-hexynyl, and the alkyne groups exemplified below.

[0024] (When the alkynyl group with 2 to 10 carbon atoms is R 1, * indicates the bonding position to the nitrogen atom. When the alkynyl group with 2 to 10 carbon atoms is Z 1, * indicates the bonding position to the aromatic ring combination.)

[0025] In formula (A), R1 is preferably an alkynyl group with 2 to 10 hydrogen atoms or carbon atoms.

[0026] In formula (A), X represents a single bond or an oxygen atom. In formula (A), Ar7 is the same group as Ar1 and Ar2 when X is a single bond, and represents phenyl or naphthyl when X is an oxygen atom.

[0027] As shown in formula (A), for example, as exemplified by the compounds described below.

[0028] [The compound shown in formula (B)] In formula (B), Ar3 to Ar6 are defined in the same way as Ar1 and Ar2 mentioned above, and each independently represents a group consisting of one or more aromatic rings with 6 to 30 carbon atoms that can be substituted by Z1. It is preferred that Ar3 to Ar6 are of the same type. Furthermore, each of Ar3 to Ar6 independently represents a group consisting of one or more aromatic rings with 6 to 30 carbon atoms containing a benzene ring that can be substituted by Z1. In formula (B), R2 and R3 are defined the same as R1 as described above. R2 and / or R3 are preferably alkynyl groups with 2 to 10 hydrogen atoms or carbon atoms. While R2 and R3 can be dissimilar groups, they are preferably the same group.

[0029] In formula (B), Y represents a single bond or a divalent group that can be substituted by Z 2. Such a divalent group is a group selected from the group consisting of alkyl, phenyl, naphthyl, anthracene, sulfonyl, carbonyl, oxygen atom (ether group) and sulfur atom (thioether group) with 1 to 15 carbon atoms, or a group consisting of such combinations. When substitution is performed by substituent Z2, there may be more than one substituent Z2. The substituent Z2 is selected from at least one group consisting of alkyl groups having 1 to 10 carbon atoms and fluoroalkyl groups having 1 to 10 carbon atoms. Examples of fluoroalkyl groups with 1 to 10 carbon atoms include perfluoromethyl, perfluoroethyl, perfluoropropyl, and perfluorobutyl. The aforementioned Z2 is preferably methyl or perfluoromethyl. In equation (B), n1, n2, m1, and m2 represent 0 or 1. All of n1, n2, m1, and m2 cannot be 0 at the same time. It is preferable that at least one of n1 and n2 is 1 and at least one of m1 and m2 is 1.

[0030] The aforementioned divalent base can be a single type, or it can be a combination of two or more types of bases. Examples of the aforementioned combinations include, for instance, bases as illustrated below, but are not limited to these.

[0031] (* indicates the bond position of the aromatic ring)

[0032] As a compound as shown in formula (B), for example, the following compounds can be exemplified.

[0033] [Synthesis of the compound shown in formula (A) or formula (B)] As a method for synthesizing the compound shown in formula (A) or formula (B), for example, a method can be given by reacting the amine compound or diamine compound shown in formula (C) to (E) with the compound shown in formula (G) to introduce a substituent R1, and then reacting the compound shown in formula (F) to introduce a substituent Ar1. The order in which substituent R1 and substituent Ar1 are introduced can be the reverse of that described above, and can be chosen appropriately.

[0034] X, Y, Ar1, and R1 are as described above. Ar8 is the same as Ar7 in the aforementioned equation (A). Z1 and Z2 are detachable groups such as hydroxyl, halogen, and sulfonic acid groups, with hydroxyl being preferred for Z1 and halogen being preferred for Z2.

[0035] The reaction products preferred for use in this invention are illustrated by way of examples.

[0036] [solvent] As a solvent for the resist underlayer film forming composition of the present invention, any solvent capable of dissolving the above-mentioned reaction products may be used without particular limitation. In particular, for the resist underlayer film forming composition of the present invention used in a uniform solution state, it is preferable to use a solvent commonly used in photolithography steps when considering the coating performance.

[0037] Examples of such solvents include methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, methyl isobutyl methanol (Carbinol), propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxylate, ethyl hydroxylate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, methyl 3-methyl... Ethyl oxypropionate, 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether, ethyl lactate, propyl lactate, isopropyl lactate, lact Butyl acetate, isobutyl lactate, methyl formate, ethyl formate, propyl formate, isopropyl formate, butyl formate, isobutyl formate, pentyl formate, isoamyl formate, methyl acetate, ethyl acetate, amyl acetate, isoamyl acetate, hexyl acetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, butyl propionate, isobutyl propionate, methyl butyrate, ethyl butyrate, propyl butyrate, isopropyl butyrate, butyl butyrate, isobutyl butyrate, ethyl hydroxyethyl acetate, ethyl 2-hydroxy-2-methylpropionate, methyl 3-methoxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutyrate, ethyl methoxyethyl acetate, ethyl ethoxyethyl acetate 3-Methoxypropionate, 3-ethoxypropionate, 3-methoxypropionate, 3-methoxybutylacetate, 3-methoxypropylacetate, 3-methyl-3-methoxybutylacetate, 3-methyl-3-methoxybutylpropionate, 3-methyl-3-methoxybutylbutyrate, methyl acetoacetate, toluene, xylene, methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, 2-heptanone, 3-heptanone, 4-heptanone, cyclohexanone, N,N-dimethylformamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, 4-methyl-2-pentanol, and γ-butyrolactone, etc. These solvents can be used alone or in combination of two or more.

[0038] Also, it can be used with the following compounds as described in WO2018 / 131562A1. (In formula (i), R4, R5 and R6 represent alkyl groups with 1 to 20 carbon atoms that can be interrupted by hydrogen or oxygen atoms, sulfur atoms or amide bonds. They can be the same or different from each other, and can also be bonded to each other to form a ring structure.)

[0039] Examples of alkyl groups having 1 to 20 carbon atoms include straight-chain or branched alkyl groups that may or may not have substituents, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, isohexyl, n-heptyl, n-octyl, cyclohexyl, 2-ethylhexyl, n-nonyl, isononyl, p-tert-butylcyclohexyl, n-decyl, n-dodecylnonyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, octadecyl, nonadecanyl, and eicosyl. Alkyl groups having 1 to 12 carbon atoms are preferred, alkyl groups having 1 to 8 carbon atoms are more preferred, and alkyl groups having 1 to 4 carbon atoms are even more preferred.

[0040] Alkyl groups having 1 to 20 carbon atoms interrupted by oxygen, sulfur, or amide bonds can be exemplified by those containing the structural units -CH₂-O-, -CH₂-S-, -CH₂-NHCO-, or -CH₂-CONH-. -O-, -S-, -NHCO-, or -CONH- may occupy one or more units in the aforementioned alkyl groups. Specific examples of alkyl groups with 1 to 20 carbon atoms interrupted by -O-, -S-, -NHCO-, or -CONH- units include methoxy, ethoxy, propoxy, butoxy, methyl thio, ethyl thio, propyl thio, butyl thio, methyl carbonylamino, ethyl carbonylamino, propyl carbonylamino, butyl carbonylamino, methyl amino carbonyl, ethyl amino carbonyl, propyl amino carbonyl, butyl amino carbonyl, etc., and further include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, or octadecyl, each of which is further substituted by methoxy, ethoxy, propoxy, butoxy, methyl thio, ethyl thio, propyl thio, butyl thio, methyl carbonylamino, ethyl carbonylamino, methyl amino carbonyl, ethyl amino carbonyl, etc. Preferably, the compounds are methoxy, ethoxy, methyl thio, or ethyl thio, and more preferably methoxy or ethoxy.

[0041] From the perspective that these solvents have relatively high boiling points, they are effective in imparting high intercalation or high planarization properties to the composition of the inhibitor lower film.

[0042] The following are specific examples of the preferred compounds represented by formula (i).

[0043] Of the above, 3-methoxy-N,N-dimethylpropionic acid, N,N-dimethylisobutylamide and The following formula: The compound shown is preferred, and 3-methoxy-N,N-dimethylpropionic acid and N,N-dimethylisobutylamide are particularly preferred as compounds of formula (i).

[0044] These solvents can be used alone or in combination of two or more. Solvents with a boiling point above 160°C are preferred, including propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, butyl lactate, cyclohexanone, 3-methoxy-N,N-dimethylpropionic acid, N,N-dimethylisobutylamide, 2,5-dimethylhexane-1,6-dimethyldiacetate (DAH; CAS, 89182-68-3), and 1,6-diethoxyhexane (CAS, 6222-17-9). Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and N,N-dimethylisobutylamide are particularly preferred.

[0045] [Cross-linking agent component] The inhibitor lower film forming composition of the present invention may contain a crosslinking agent. Examples of such crosslinking agents include melamine-based, substituted urea-based, or polymer-based agents. Preferably, the crosslinking agent has at least two substituents that form crosslinks, and examples include compounds such as methoxymethylated ethylene glycol urea, butoxymethylated ethylene glycol urea, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, or methoxymethylated thiourea. Furthermore, condensates of these compounds may also be used.

[0046] Furthermore, a crosslinking agent with high heat resistance can be used as the aforementioned crosslinking agent. Preferably, a compound containing a crosslinking-forming substituent with an aromatic ring (e.g., benzene ring, naphthalene ring) within the molecule can be used as the crosslinking agent with high heat resistance.

[0047] The compound is a compound having a partial structure of the following formula (4), or a polymer or oligomer having repeating units of the following formula (5). R11, R12, R13, and R14 are hydrogen atoms or alkyl groups having 1 to 10 carbon atoms, and the alkyl groups exemplified above can be used. n11 represents an integer from 1 to 4, n12 represents an integer from 1 to (5-n11), and (n11+n12) represents an integer from 2 to 5. n13 represents an integer from 1 to 4, n14 represents an integer from 0 to (4-n13), and (n13+n14) represents an integer from 1 to 4. The number of repeating unit structures in oligomers and polymers can be in the range of 2 to 100 or 2 to 50.

[0048] The compounds, polymers, and oligomers of formulas (4) and (5) are illustrated below.

[0049] The above-mentioned compounds can be obtained from products manufactured by Asahi Organic Materials Co., Ltd. and Honshu Chemical Co., Ltd. For example, among the above-mentioned crosslinking agents, the compound of formula (4-24) can be obtained from the trade name TM-BIP-A of Asahi Organic Materials Co., Ltd.

[0050] In addition to the compounds mentioned above, compounds with the following structures can also be used as crosslinking agents.

[0051]

[0052] The amount of crosslinking agent added varies depending on the coating solvent used, the underlying substrate used, the required solution viscosity, the required film shape, etc., but is preferably 0.001 to 80% by mass, and more preferably 0.01 to 50% by mass, relative to the total solids content. Although these crosslinking agents can cause crosslinking reactions through self-condensation, they will also undergo crosslinking reactions with crosslinking substituents when crosslinking substituents are present in the reaction products of the present invention.

[0053] [Acids and / or acid-generating agents] The resistive lower film forming composition of the present invention may contain acid and / or acid generating agent. Examples of acids include p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium p-toluenesulfonic acid, salicylic acid, 5-sulfosalicylic acid, 4-phenolsulfonic acid, camphorsulfonic acid, 4-chlorobenzenesulfonic acid, benzenedisulfonic acid, 1-naphthalenesulfonic acid, citric acid, benzoic acid, hydroxybenzoic acid, and naphtholic acid.

[0054] Acids may be used in single-class or in combination of two or more. The amount of the acid is generally 0.0001 to 20% by mass relative to the total solid content, preferably 0.0005 to 10% by mass, and even more preferably 0.01 to 5% by mass.

[0055] Examples of acid-generating agents include thermal acid-generating agents and photoacid-generating agents. Examples of thermal acid-generating agents include 2,4,4,6-tetrabromocyclohexadienone, benzoin toluenesulfonate, 2-nitrobenzyl toluenesulfonate, pyridinium-4-hydroxybenzenesulfonate, pyridinium-p-toluenesulfonate, pyridinium trifluoromethanesulfonate, N-(4-methoxybenzyl)-N,N-dimethylaniline trifluoromethanesulfonate, and other organic alkyl sulfonate esters.

[0056] The photoacid generator produces acid during resist exposure. Therefore, the acidity of the lower film can be adjusted. This is one method to match the acidity of the lower film with that of the upper resist. Furthermore, by adjusting the acidity of the lower film, the pattern shape of the resist formed on the upper layer can be adjusted.

[0057] Examples of photoacid generators included in the resist lower layer film forming composition of the present invention include onium salt compounds, sulfonium imine compounds, and disulfonyl azomethane compounds.

[0058] Examples of onion salt compounds include diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethane sulfonate, diphenyliodonium nonafluoron-butane sulfonate, diphenyliodonium perfluoron-octane sulfonate, diphenyliodonium camphor sulfonate, bis(4-tert-butylphenyl)iodonium camphor sulfonate, and bis(4-tert-butylphenyl)iodonium trifluoromethane sulfonate, as well as thiodonium salt compounds such as triphenylthionium hexafluoroantimonate, triphenylthionium nonafluoron-butane sulfonate, triphenylthionium camphor sulfonate, and triphenylthionium trifluoromethane sulfonate.

[0059] Examples of sulfonamide compounds include N-(trifluoromethanesulfonoxy)succinate imine, N-(nonafluoron-butanesulfonoxy)succinate imine, N-(camphorsulfonoxy)succinate imine, and N-(trifluoromethanesulfonoxy)naphthalenedimethylimine.

[0060] Examples of disulfonyl azomethane compounds include bis(trifluoromethylsulfonyl)azomethane, bis(cyclohexylsulfonyl)azomethane, bis(phenylsulfonyl)azomethane, bis(p-toluenesulfonyl)azomethane, bis(2,4-dimethylbenzenesulfonyl)azomethane, and methylsulfonyl-p-toluenesulfonylazomethane.

[0061] Acid-generating agents may be used in combination of one type or two or more types. When using an acid-generating agent, the proportion is 0.01 to 5 parts by mass, or 0.1 to 3 parts by mass, or 0.5 to 1 part by mass relative to 100 parts by mass of the solid component of the inhibitor lower film forming composition.

[0062] [Other ingredients] In the resistive film-forming composition of the present invention, if it is desired to avoid pinholes or streaks and to further improve the coatability of uneven surfaces, a surfactant may be added. Examples of nonionic surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene hexadecyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkyl allyl ethers such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether; polyoxyethylene-polyoxypropylene block copolymers; sorbitol monolaurate, sorbitol monopalmitate, sorbitol monostearate, sorbitol monooleate, sorbitol monooleate, sorbitol trioleate, and sorbitol tristearate; and polyoxyethylene sorbitol fatty acid esters such as polyoxyethylene sorbitol monolaurate, polyoxyethylene sorbitol monopalmitate, polyoxyethylene sorbitol monostearate, polyoxyethylene sorbitol trioleate, and polyoxyethylene sorbitol tristearate. Other examples include EFTOPEF301, EF303, and EF352 (Tochem). Fluorinated surfactants such as Megafac F171, F173, R-30N, R-40, R-40N, R-40LM (manufactured by DIC), FLUORAD FC430, FC431 (manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass), and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.) are used. The amount of these surfactants incorporating is generally 2.0% by mass or less, preferably 1.0% by mass or less, relative to the total solids content of the underlayer membrane material. These surfactants can be used alone or in combination of two or more. When using surfactants, the proportion is 0.0001 to 5 parts by mass, or 0.001 to 1 part by mass, or 0.01 to 0.5 parts by mass relative to 100 parts by mass of the solid component of the inhibitor underlayer film forming composition.

[0063] In the resist underfilm formation composition of the present invention, light absorbers, rheology modifiers, adhesion promoters, etc., may be added. Rheology modifiers are effective in improving the flowability of the underfilm formation composition. Adhesion promoters are effective in improving the adhesion between the semiconductor substrate or resist and the underfilm.

[0064] As light absorbers, examples include those listed in "Technology and Market of Industrial Pigments" (published by CMC) or "Dye Handbook" (edited by the Organic Synthetic Chemistry Society), such as CI Disperse Yellow 1, 3, 4, 5, 7, 8, 13, 23, 31, 49, 50, 51, 54, 60, 64, 66, 68, 79, 82, 88, 90, 93, 102, 114 and 124; CI Disperse Orange 1, 5, 13, 25, 29, 30, 31, 44, 57, 72 and 73; CI Disperse Red 1, 5, 7, 13, 17, 19, 43, 50, 54, 58, 65, 72, 73, 88, 117, 137, 143, 199 and 210; CI Disperse Violet 43; CI Disperse Blue 96; CI Fluorescent Brightening Agent 112, 135 and 163; CI Solvent Orange 2 and 45; CI Solvent Red 1, 3, 8, 23, 24, 25, 27 and 49; CIPigment Green 10; CIPigment Brown 2, etc. The above-mentioned absorbers are generally formulated at a ratio of 10% by mass or less, and more preferably 5% by mass or less, relative to the total solid content of the film-forming composition under the resist.

[0065] Rheology modifiers are primarily used to improve the flowability of the resist underlayer film formation composition, especially during the baking process, to improve the uniformity of the resist underlayer film thickness or to enhance the filling effect of the resist underlayer film formation composition within the pores. Specific examples include phthalic acid derivatives such as dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dihexyl phthalate, and butyl isodecanyl phthalate; adipic acid derivatives such as di-n-butyl adipic acid, diisobutyl adipic acid, diisooctyl adipic acid, and octyldecyl adipic acid; maleic acid derivatives such as di-n-butyl maleate, diethyl maleate, and dinonyl maleate; oleic acid derivatives such as methyl oleate, butyl oleate, and tetrahydrofurfuryl oleate; and stearic acid derivatives such as n-butyl stearate and glyceryl stearate. These rheology modifiers are generally added at a ratio of less than 30% by mass relative to the total solids content of the film-forming composition under the resist.

[0066] Next, the additives are mainly used to improve the adhesion between the substrate or the resist and the composition of the underlying resist film, especially when the resist is to be prevented from peeling off during development. Specific examples include chlorosilanes such as trimethylchlorosilane, dimethylhydroxymethylchlorosilane, methyldiphenylchlorosilane, and chloromethyldimethylchlorosilane; alkoxysilanes such as trimethylmethoxysilane, dimethyldiethoxysilane, methyldimethoxysilane, dimethylhydroxymethylethoxysilane, diphenyldimethoxysilane, and phenyltriethoxysilane; hexamethyldisilazane; N,N'-bis(trimethylsilyl)urea; dimethyltrimethylsilylamine; and trimethylsilyl... The additives include silanes such as imidazole, hydroxymethyltrichlorosilane, γ-chloropropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and γ-epoxypropoxypropyltrimethoxysilane; heterocyclic compounds such as benzotriazole, benzimidazole, indazole, imidazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, urazole, thiouracil, mercaptoimidazole, and mercaptopyrimidine; or urea such as 1,1-dimethylurea and 1,3-dimethylurea; or thiourea compounds. These adsorption aids are generally formulated at a ratio of less than 5% by mass, preferably less than 2% by mass, relative to the total solids content of the film-forming composition under the inhibitor.

[0067] The solid content of the inhibitor underlayer film-forming composition of the present invention is generally set at 0.1 to 70% by mass, preferably 0.1 to 60% by mass. The solid content refers to the total content of the inhibitor underlayer film-forming composition excluding the solvent. The preferred order of the proportions of the above-mentioned reaction products in the solid content is 1 to 100% by mass, 1 to 99.9% by mass, 50 to 99.9% by mass, 50 to 95% by mass, and 50 to 90% by mass.

[0068] One way to assess whether the resistive underlayer membrane forming composition is a homogeneous solution is to observe the permeability of a specific microfilter. However, the resistive underlayer membrane forming composition of the present invention presents a homogeneous solution state when passing through a microfilter with a pore size of 0.1 μm.

[0069] Examples of materials for the aforementioned microfilters include fluorinated resins such as PTFE (polytetrafluoroethylene ethyl ether) and PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), PE (polyethylene), UPE (ultra-high molecular weight polyethylene), PP (polypropylene), PSF (polyurethane), PES (polyether ether), and nylon, with PTFE (polytetrafluoroethylene ethyl ether) being the most preferred.

[0070] [Resistor underlayer film and semiconductor device manufacturing method] The following describes the manufacturing method of the resist underlayer film and the semiconductor device using the resist underlayer film formation composition of the present invention.

[0071] The resist underlayer film forming composition of the present invention is applied to a substrate used in the manufacture of semiconductor devices (e.g., silicon wafer substrate, silicon / silicon dioxide coated substrate, silicon nitride substrate, glass substrate, ITO substrate, polyimide substrate, and low-k material coated substrate, etc.) using a suitable coating method such as a spin coater or coater, and then formed by firing. Suitable firing conditions are selected from firing temperatures of 80°C to 500°C and firing times of 0.3 to 60 minutes. Preferably, the firing temperature is 150°C to 400°C and the firing time is 0.5 to 2 minutes. The thickness of the formed underlayer film is, for example, 10 to 1000 nm, or 20 to 500 nm, or 30 to 300 nm, or 50 to 200 nm. The firing environment can be either atmospheric or nitrogen-based.

[0072] Furthermore, an inorganic resist film (hard photomask) can also be formed on the organic resist film of the present invention. For example, in addition to the method of forming the silicon-containing resist film (inorganic resist film) composition as described in WO2009 / 104552A1 by spin coating, a Si-based inorganic material film can also be formed by CVD or the like.

[0073] Furthermore, by coating and firing the resist lower layer film forming composition of the present invention onto a semiconductor substrate (so-called a step substrate) containing a step portion and a non-step portion, a resist lower layer film with a step portion and a non-step portion having a step size in the range of 3 to 50 nm can be formed.

[0074] Next, a resist film, such as a photoresist layer, is formed on the lower resist film. The photoresist layer can be formed by a known method, that is, by coating and firing a photoresist composition solution onto the lower film. The thickness of the photoresist film is, for example, 50 to 10000 nm, or 100 to 2000 nm, or 200 to 1000 nm.

[0075] As the photoresist formed on the upper layer of the resist film, it is not particularly limited to any photoresist that is photosensitive to the light used for exposure. Either negative or positive photoresist can be used. Positive photoresists are made from phenolic varnish resin and 1,2-naphthoquinone diazide sulfonate; chemically broadening photoresists are made from binders having a group that increases the alkali dissolution rate through acid decomposition and photoacid generating agents; chemically broadening photoresists are made from low-molecular-weight compounds that increase the alkali dissolution rate of photoresist through acid decomposition, alkali-soluble binders, and photoacid generating agents; and chemically broadening photoresists are made from binders having a group that increases the alkali dissolution rate of photoresist through acid decomposition, low-molecular-weight compounds that increase the alkali dissolution rate of photoresist through acid decomposition, and photoacid generating agents, etc. Examples include APEX-E manufactured by Shipley Corporation, PAR710 manufactured by Sumitomo Chemical Industries, Ltd., and SEPR430 manufactured by Shin-Etsu Chemical Industries, Ltd. Furthermore, examples include fluorinated polymer photoresists described in Proc. SPIE, Vol. 3999, 330-334 (2000), Proc. SPIE, Vol. 3999, 357-364 (2000), or Proc. SPIE, Vol. 3999, 365-374 (2000).

[0076] Secondly, a resist pattern is formed by irradiation and development using light or electron beams. First, exposure is performed through a predetermined photomask. Exposure can be performed using near-ultraviolet, far-ultraviolet, or extreme ultraviolet light (e.g., EUV (wavelength 13.5 nm)). Specifically, KrF excimer lasers (wavelength 248 nm), ArF excimer lasers (wavelength 193 nm), and F2 excimer lasers (wavelength 157 nm) can be used. Among these, ArF excimer lasers (wavelength 193 nm) and EUV (wavelength 13.5 nm) are preferred. After exposure, post-exposure baking can be performed if necessary. Post-exposure baking can be performed at a suitable temperature of 70°C to 150°C for 0.3 to 10 minutes.

[0077] Furthermore, in this invention, an electron line lithography resist can be used instead of a photoresist. As an electron line resist, both negative and positive types can be used. The resist types include: chemically broadening resists formed by an acid-generating agent and a binder having a group that changes the alkali dissolution rate through acid decomposition; chemically broadening resists formed by an alkali-soluble binder, an acid-generating agent, and a low-molecular-weight compound that changes the alkali dissolution rate of the resist through acid decomposition; chemically broadening resists formed by an acid-generating agent, a binder having a group that changes the alkali dissolution rate through acid decomposition, and a low-molecular-weight compound that changes the alkali dissolution rate of the resist through acid decomposition; non-chemically broadening resists formed by a binder having a group that changes the alkali dissolution rate through electron line decomposition; and non-chemically broadening resists formed by a binder having a portion that changes the alkali dissolution rate through electron line cutting. The same resist pattern can be formed when using such electron beam resists as when using photoresist with the irradiation source as an electron beam.

[0078] Next, development is performed using a developer. In this way, for example, when using a positive photoresist, the exposed photoresist is removed to form a photoresist pattern.

[0079] Examples of developing solutions include aqueous solutions of alkali metal hydroxides such as potassium hydroxide and sodium hydroxide, aqueous solutions of tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline, and other quaternary ammonium hydroxides, as well as alkaline aqueous solutions of amines such as ethanolamine, propylamine, and ethylenediamine. Furthermore, surfactants may be added to these developing solutions. Suitable developing conditions include a temperature of 5 to 50°C and a development time of 10 to 600 seconds.

[0080] Then, the pattern of the photoresist (upper layer) formed in this way can be used as a protective film to remove the inorganic lower layer (intermediate layer). Next, the film formed by the patterned photoresist and the inorganic lower layer (intermediate layer) can be used as a protective film to remove the organic lower layer (lower layer). Finally, the patterned inorganic lower layer (intermediate layer) and organic lower layer (lower layer) can be used as protective films to process the semiconductor substrate.

[0081] First, the inorganic lower layer (intermediate layer), to which the photoresist has been removed, is dry-etched to expose the semiconductor substrate. Gases that can be used for dry etching of the inorganic lower layer include tetrafluoromethane (CF4), perfluorocyclobutane (C4F8), perfluoropropane (C3F8), trifluoromethane, carbon monoxide, argon, oxygen, nitrogen, sulfur hexafluoride, difluoromethane, nitrogen trifluoride, chlorine trifluoride, chlorine, trichloroborane, and dichloroborane. Halogen-based gases are preferred for dry etching of the inorganic lower layer, with fluorine-based gases being even more advantageous. Examples of fluorine-based gases include tetrafluoromethane (CF4), perfluorocyclobutane (C4F8), perfluoropropane (C3F8), trifluoromethane, and difluoromethane (CH2F2).

[0082] Subsequently, the organic underlayer is removed by using a film formed from the patterned photoresist and the inorganic underlayer as a protective film. Dry etching of the organic underlayer (underlayer) with an oxygen-based gas is preferred. Inorganic underlayers containing a large amount of silicon atoms are difficult to remove by dry etching with an oxygen-based gas.

[0083] Finally, the semiconductor substrate is processed. It is preferable to process the semiconductor substrate using dry etching with fluorine-based gases. Examples of fluorine-based gases include tetrafluoromethane (CF4), perfluorocyclobutane (C4F8), perfluoropropane (C3F8), trifluoromethane, and difluoromethane (CH2F2).

[0084] Furthermore, an organic anti-reflection film can be formed on the upper layer of the photoresist film before the photoresist is formed. There are no particular restrictions on the composition of the anti-reflection film used herein, and any composition conventionally used in photolithography can be used. Also, conventional methods, such as coating and firing, can be used to form the anti-reflection film.

[0085] In this invention, after an organic lower layer film is formed on a substrate, an inorganic lower layer film is formed on top of it, and a photoresist can be further coated on top of it. This narrows the pattern width of the photoresist, and to prevent pattern collapse, even with a thin layer of photoresist, substrate processing becomes possible by selecting an appropriate etching gas. For example, it is possible to process the photoresist lower layer film using a fluorine-based gas with a sufficiently fast etching rate for the photoresist, and it is also possible to process a substrate using a fluorine-based gas with a sufficiently fast etching rate for the inorganic lower layer film. Furthermore, it is possible to process a substrate using an oxygen-based gas with a sufficiently fast etching rate for the organic lower layer film.

[0086] The resist lower layer film formed by the resist lower layer film forming composition absorbs light of the wavelength used in photolithography. In this case, it functions as a reflective anti-reflection film that prevents light reflected from the substrate. Furthermore, the lower layer film formed by the resist lower layer film forming composition of the present invention can also function as a hard photomask. The lower layer film of the present invention can be used as the following layers: a layer to prevent interaction between the substrate and the photoresist; a layer to prevent adverse effects on the substrate, the material used in the photoresist, or the substance generated during exposure to the photoresist; a layer to prevent diffusion of the upper photoresist layer onto the substance generated from the substrate during heating and firing; and a barrier layer to reduce the poisoning effect of the photoresist layer through the dielectric layer of the semiconductor substrate.

[0087] Furthermore, the lower layer film formed by the resist lower layer film formation composition is suitable for forming substrates with through holes used in dual damascene processes, and can be used as an insert material to fill the holes without gaps. It can also be used as a planarization material to planarize the surface of semiconductor substrates with uneven surfaces. [Example]

[0088] The weight-average molecular weight and polydispersity shown in Synthesis Example 1 below were determined by gel permeation chromatography (hereinafter referred to as GPC). The determination was performed using a GPC apparatus manufactured by Tosoh Corporation, and the determination conditions are as follows. GPC tubing: TSKgel SuperMultipore [registered trademark] Hz-N (Tosoh Corporation) Column temperature: 40℃ Solvent: Tetrahydrofuran (THF) Flow rate: 0.35 mL / min Standard sample: Polystyrene (Tosoh Corporation)

[0089] (Synthesis example 1) Under nitrogen atmosphere, 2,2-bis[4-(4-aminophenoxy)phenyl]propane (50.00 g, 0.1219 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), 9-fluorenol (88.85 g, 0.4876 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and methanesulfonic acid (25.77 g, 0.2682 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a 1000 mL four-necked flask. Propylene glycol 1-monomethyl ether 2-acetate (268.89 g, manufactured by Kanto Chemical Co., Ltd.) and 1-methyl-2-pyrrolidone (115.24 g, manufactured by Tokyo Chemical Industry Co., Ltd.) were then added. The mixture was stirred and heated to 160 °C to dissolve the precipitate and initiate the reaction. After 24 hours, the mixture was cooled to room temperature and allowed to redefine in a mixture of methanol (3600 g, manufactured by Kanto Chemical Co., Ltd.) and ammonia (190 g, manufactured by Kanto Chemical Co., Ltd.). The precipitate obtained by filtration was dried in a vacuum dryer at 60°C for 10 hours to obtain 95.5 g of a compound having the structure shown in formula (a) below (hereinafter referred to as BAPP-4F in this specification). The weight average molecular weight Mw of BAPP-4F, converted to polystyrene by GPC, was 720, and the polydispersity Mw / Mn was 1.10.

[0090] (Synthesis example 2) Under nitrogen atmosphere, 1,3-bis(4-aminophenoxy)propane (40.00 g, 0.1549 mol, manufactured by Wako Pure Chemical Industries, Ltd.), 9-fluorenol (112.87 g, 0.6194 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and methanesulfonic acid (32.74 g, 0.3406 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a 1000 mL four-necked flask. Propylene glycol 1-monomethyl ether 2-acetate (303.17 g, manufactured by Kanto Chemical Co., Ltd.) and 1-methyl-2-pyrrolidone (129.93 g, manufactured by Tokyo Chemical Industry Co., Ltd.) were then added. The mixture was stirred and heated to 160 °C to dissolve the precipitate and initiate the reaction. After 24 hours, the mixture was cooled to room temperature and allowed to redefine in a mixture of methanol (3600 g, manufactured by Kanto Chemical Co., Ltd.) and ammonia (190 g, manufactured by Kanto Chemical Co., Ltd.). The precipitate obtained by filtration was dried at 60°C for 10 hours using a vacuum dryer to obtain 74.24 g of a compound having the structure shown in formula (b) below (hereinafter referred to as DA-3MG-4F in this specification). The weight average molecular weight Mw of DA-3MG-4F, converted to polystyrene by GPC, was 660, and the polydispersity Mw / Mn was 1.40.

[0091] (Synthesis example 3) Under nitrogen atmosphere, 1,5-bis(4-aminophenoxy)pentane (40.00 g, 0.1397 mol, manufactured by Wako Pure Chemical Industries, Ltd.), 9-fluorenol (101.80 g, 0.5587 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and methanesulfonic acid (29.53 g, 0.3073 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a 1000 mL four-necked flask. Propylene glycol 1-monomethyl ether 2-acetate (279.84 g, manufactured by Kanto Chemical Co., Ltd.) and 1-methyl-2-pyrrolidone (119.93 g, manufactured by Tokyo Chemical Industry Co., Ltd.) were then added. The mixture was stirred and heated to 160 °C to dissolve the precipitate and initiate the reaction. After 24 hours, the mixture was cooled to room temperature and allowed to redefine the precipitate in a mixture of methanol (3600 g, manufactured by Kanto Chemical Co., Ltd.) and ammonia (190 g, manufactured by Kanto Chemical Co., Ltd.). The precipitate obtained by filtration was dried in a vacuum dryer at 60°C for 10 hours to obtain 77.10 g of a compound having the structure shown in formula (c) below (hereinafter referred to as DA-5MG-4F in this specification). The weight average molecular weight Mw of DA-5MG-4F, converted to polystyrene by GPC, was 680, and the polydispersity Mw / Mn was 1.40.

[0092] (Synthesis Example 4) Under nitrogen atmosphere, 2,2-bis[4-(4-aminophenoxy)phenyl]propane (50.00 g, 0.1219 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), potassium carbonate (134.66 g, 0.974 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and hydroquinone (0.75 g, 0.007 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a 1000 mL four-necked flask. Dimethylformamide (500.00 g, manufactured by Kanto Chemical Co., Ltd.) was then added. After stirring, the mixture was heated to 40 °C, and propyne bromide (101.423 g, 0.853 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise through a titration funnel to initiate the reaction. After 24 hours, the mixture was cooled to room temperature. After removing the potassium carbonate residue, toluene (500.00 g, manufactured by Kanto Chemical Co., Ltd.) was added, and the mixture was washed with 500 g of pure water. The toluene solution was recovered and removed by vacuum distillation to obtain 55.3 g of the intermediate product (hereinafter referred to as BAPP-PG in this specification). Under nitrogen atmosphere, BAPP-PG (40.00 g, 0.070 mol), 9-fluorenol (25.92 g, 0.142 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and methanesulfonic acid (13.67 g, 0.1423 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a 1000 mL four-necked flask. Propylene glycol 1-monomethyl ether 2-acetate (145.7 g, manufactured by Kanto Chemical Co., Ltd.) was then added. The mixture was stirred and heated to 140 °C to dissolve the precipitate and initiate the reaction. After 24 hours, the mixture was cooled to room temperature and reprecipitated in a mixture of methanol (3600 g, manufactured by Kanto Chemical Co., Ltd.) and ammonia (190 g, manufactured by Kanto Chemical Co., Ltd.). The precipitate was filtered and dried at 40 °C for 10 hours using a vacuum dryer to obtain 38.3 g of a compound having the structure shown in formula (d) below (hereinafter referred to as BAPP-PG2F in this specification). The weight-average molecular weight (Mw) of BAPP-PG2F, converted to polystyrene by GPC, was 1270, and the polydispersity (Mw / Mn) was 1.30.

[0093] (Example 1) 1.00 g of the compound shown in formula (a) and 0.002 g of surfactant (manufactured by DIC, product name: Megafac R-30N, fluorinated surfactant) were dissolved in 4.92 g of propylene glycol monomethyl ether and 11.47 g of propylene glycol monomethyl ether acetate to prepare a composition for forming an inhibitor lower film.

[0094] (Example 2) 1.00 g of the compound shown in formula (a), 0.20 g of a polymeric crosslinking agent having the structure shown in formula (e) (hereinafter referred to as TMOM-BPp in this specification), and 0.002 g of a surfactant (manufactured by DIC Corporation, trade name: Megafac R-30N, fluorinated surfactant) were dissolved in 5.88 g of propylene glycol monomethyl ether and 13.72 g of propylene glycol monomethyl ether acetate to prepare a resistive lower film forming composition.

[0095] (Example 3) 1.00 g of the compound shown in formula (b) and 0.002 g of surfactant (product name: Megafac R-30N, fluorinated surfactant manufactured by DIC) were dissolved in 4.55 g of propylene glycol monomethyl ether and 10.63 g of propylene glycol monomethyl ether acetate to prepare a composition for forming the lower layer film of the inhibitor.

[0096] (Example 4) 1.00 g of the compound shown in formula (c) and 0.002 g of surfactant (product name: Megafac R-30N, fluorinated surfactant manufactured by DIC) were dissolved in 4.71 g of propylene glycol monomethyl ether and 10.99 g of propylene glycol monomethyl ether acetate to prepare a composition for forming the lower layer film of the inhibitor.

[0097] (Example 5) 1.00 g of the compound shown in formula (d) and 0.002 g of surfactant (product name: Megafac R-30N, fluorinated surfactant manufactured by DIC) were dissolved in 4.92 g of propylene glycol monomethyl ether and 11.47 g of propylene glycol monomethyl ether acetate to prepare a composition for forming the lower layer film of the inhibitor.

[0098] (Comparative Example 1) 1.00 g of the polymer shown in formula (f) below, 0.20 g of 4,4'-(1-methylethidium)bis[2,6-bis[(2-methoxy-1-methylethoxy)methyl]-phenol as a crosslinking agent, 0.033 g of pyridinium-p-phenol sulfonate as an acid catalyst, and 0.001 g of surfactant (manufactured by DIC Corporation, trade name: Megafac R-30N, fluorinated surfactant) were dissolved in 4.93 g of propylene glycol monomethyl ether and 11.52 g of propylene glycol monomethyl ether acetate to prepare an inhibitor lower film forming composition.

[0099] (Dissociation test of photoresist solvent) The resist underlayer films prepared in Examples 1-5 and Comparative Example 1 were formed into compositions and coated onto silicon wafers using a spin coater. The wafers were baked at 240°C for 1 minute on a hot plate, and then further baked at 400°C for 1 minute to form a resist underlayer film (film thickness 0.10 μm). This resist underlayer film was then immersed in propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate, solvents used as resists, and confirmed to be insoluble in these solvents.

[0100] (Covering test on stepped substrate) As an evaluation of step coverage, a SiO2 substrate with a trench pattern having a width of 50 nm, a spacing of 50 nm, and a depth of 200 nm was used. The coating film thickness of the densely patterned region (DENSE) with a trench width of 100 nm and a spacing of 175 nm was compared with that of the open region (OPEN) 1400 μm away without a pattern. The resist underlayer film forming composition of Examples 1-5 and Comparative Example 1 was coated on the above substrate to a film thickness of 100 nm, and then baked at 240°C for 60 seconds, and further baked at 400°C for 60 seconds. The step coverage of the substrate was observed using a scanning electron microscope (S-4800) manufactured by Hitachi High Technologies, and the planarization was evaluated by measuring the film thickness difference between the densely patterned region (patterned area) and the open region (unpatterned area) of the step substrate (the coating step difference between the densely patterned region and the open region is called Bias). The film thickness and coating step difference values ​​for each region are recorded in Table 1, and SEM images of Comparative Example 1 and Example 2 are shown in Figures 1 and 2. Flatness was assessed by a smaller Bias value, indicating higher flatness.

[0101]

[0102] When comparing the coverage of the stepped substrate, the results of Examples 1-5 show that the coating step difference between the patterned area and the open area is smaller than that of Comparative Example 1, indicating that the resist underlayer film obtained from the resist underlayer film formation composition of Examples 1-5 has good planarization properties. [Industry-level availability]

[0103] The present invention provides that mixing does not occur when laminating photoresist compositions or dissimilar photoresist underlayer films, and that a composition of photoresist underlayer film is formed to improve the pattern filling properties during firing by enhancing the thermal reflow properties of the polymer.

Claims

1. A lower layer film forming composition for an inhibitor, comprising a compound of formula (B) and a solvent; (in formula (B), Ar3 to Ar6 each independently represent a group consisting of one or more aromatic rings having 6 to 30 carbon atoms that can be substituted by Z1; R2 and R3 represent hydrogen atoms, alkyl groups having 1 to 10 carbon atoms, alkenyl groups having 2 to 10 carbon atoms, or alkynyl groups having 2 to 10 carbon atoms; Y represents a single bond or a divalent group that can be substituted by Z2; n1, n2, m1, and m2 represent 0 or 1, and none of n1, n2, m1, and m2 can simultaneously be 0; Z1 is selected from at least one group consisting of halogen atoms, hydroxyl groups, cyano groups, methylamino groups, methyl ether groups, cyclic alkyl groups, phenyl groups, pyridyl groups, alkyl groups having 1 to 10 carbon atoms, alkenyl groups having 2 to 10 carbon atoms, and alkynyl groups having 2 to 10 carbon atoms). Z2 is selected from at least one group consisting of alkyl groups having 1 to 10 carbon atoms and fluoroalkyl groups having 1 to 10 carbon atoms.

2. The inhibitor lower film forming composition as claimed in claim 1, wherein in the aforementioned formula (B), Ar3 to Ar6 are each independently a group composed of one or more aromatic rings containing a benzene ring.

3. The composition of the lower layer film forming of the inhibitor as claimed in claim 1 or 2, wherein Ar3 to Ar6 in the aforementioned formula (B) are the same base.

4. The inhibitor underlayer film forming composition as claimed in claim 1 or 2, wherein the divalent group in the aforementioned formula (B) is a group selected from the group consisting of alkyl, phenyl, naphthyl, anthracene, sulfonyl, carbonyl, ether, and thioether groups, or a combination thereof, having 1 to 15 carbon atoms in a branched or straight chain.

5. The inhibitor lower film forming composition as claimed in claim 4, wherein the divalent group in the aforementioned formula (B) is any of the groups shown below (* indicates the bonding position of the aromatic ring).

6. The inhibitor underlayer film forming composition as claimed in claim 1 or 2, wherein R2 and / or R3 in the aforementioned formula (B) are hydrogen atoms or alkynyl groups having 2 to 10 carbon atoms.

7. The resistive underlayer film forming composition as claimed in claim 1 or 2, further comprising a crosslinking agent.

8. The resistive lower film forming composition as claimed in claim 1 or 2, further comprising an acid and / or an acid generating agent.

9. The composition of the lower layer film forming of the inhibitor as claimed in claim 1 or 2, wherein the solvent is a solvent with a boiling point of 160°C or higher.

10. A resistive underlayer film, characterized in that it is a sintered product of a coated film formed from a resistive underlayer film composition as claimed in any one of claims 1 to 9.

11. A method for manufacturing a semiconductor device, comprising the steps of forming a resist underlayer film on a semiconductor substrate by means of a resist underlayer film forming composition as described in any one of claims 1 to 9, forming a resist film on the substrate, forming a resist pattern by means of irradiation and development by light or electron beams, etching the resist underlayer film by means of the resist pattern, and processing the semiconductor substrate by means of the patterned resist underlayer film.

Images