Resist underlayer composition and method of forming a pattern using the same

Abstract

Disclosed are a resist underlayer composition including: a polymer including a main chain, a side chain, or both, containing a heterocycle having two or more nitrogen atoms in a ring; a compound including a moiety represented by Chemical Formula 1; and a solvent; and a method of forming a pattern using the resist underlayer composition: the definition of Chemical Formula 1 is the same as described in the embodiments.[Chemical Formula 1]

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2021-0100893 filed in the Korean Intellectual Property Office on July 30, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a resist underlayer composition and a method of forming a pattern using the resist underlayer composition. Background Art

[0004] Recently, the semiconductor industry has developed ultra-fine technology with patterns ranging from a few nanometers to tens of nanometers in size. This ultra-fine technology mainly requires efficient photolithography technology.

[0005] Photolithography is a processing method including: coating a photoresist layer on a semiconductor substrate such as a silicon wafer to form a thin layer; irradiating a mask pattern on which a device pattern is drawn with activating radiation such as ultraviolet rays; and then developing the resultant to obtain a photoresist pattern; and etching the substrate using the photoresist pattern as a protective layer to form a fine pattern corresponding to the pattern on the surface of the substrate.

[0006] To achieve ultra-fine technology, suitable patterning materials are required, and research on these materials is actively underway. For fine patterning, the resist base layer must have good, close contact with the resist to prevent resist pattern collapse even during fine patterning. In the etching process, exposure time should be shortened by having an etch rate faster than the resist or by applying a coating as thin as possible. Furthermore, sensitivity to the exposure light source should be improved to enhance patterning performance, and the light source should be highly efficient. Summary of the Invention

[0007] One embodiment provides a resist underlayer composition in which pattern collapse of the resist is not caused even in a fine patterning process, the etching process time can be shortened because the resist underlayer composition is formed into an ultra-thin layer, and coating uniformity, gap-filling characteristics, and resist pattern forming ability can be improved by improving cross-linking properties.

[0008] Another embodiment provides a method of forming a pattern using a resist underlayer composition.

[0009] A resist underlayer composition according to an embodiment includes: a polymer including a main chain, a side chain, or a main chain and a side chain including a heterocycle including two or more nitrogen atoms in a ring; a compound including a moiety represented by Chemical Formula 1; and a solvent.

[0010] [Chemical Formula 1]

[0011]

[0012] In Chemical Formula 1,

[0013] Ar1 is a group containing a heterocyclic ring,

[0014] Ar2 is a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group,

[0015] B1 and B2 are each independently a single bond, a substituted or unsubstituted C1 to C10 aliphatic hydrocarbon group, a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, or a combination thereof,

[0016] X1 to X4 are each independently hydrogen, deuterium, a hydroxyl group, a thiol group, a cyano group, a substituted or unsubstituted amino group, a halogen atom, a substituted or unsubstituted C1 to C30 aliphatic hydrocarbon group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof,

[0017] l, m and n are each independently an integer from 0 to 5, and

[0018] o is an integer from 1 to 30.

[0019] The polymer may include any one or more of the structural units represented by Chemical Formula 2 to Chemical Formula 5.

[0020] [Chemical Formula 2]

[0021]

[0022] [Chemical Formula 3]

[0023]

[0024] [Chemical Formula 4]

[0025]

[0026] [Chemical Formula 5]

[0027]

[0028] In Chemical Formulas 2 to 5,

[0029] A is a heterocyclic ring containing two or more nitrogen atoms in the ring,

[0030] R a 、R b and R ceach independently represents hydroxy, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, substituted or unsubstituted C1 to C10 heteroalkyl, substituted or unsubstituted C1 to C10 heteroalkenyl, substituted or unsubstituted C1 to C10 heteroalkynyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 heterocycloalkyl, substituted or unsubstituted C6 to C20 aryl, substituted or unsubstituted C1 to C20 heteroaryl, or a combination thereof,

[0031] L 1 To L 5 are each independently a single bond, a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C1 to C10 heteroalkylene group, a substituted or unsubstituted C3 to C20 cycloalkylene group, a substituted or unsubstituted C2 to C20 heterocycloalkylene group, a substituted or unsubstituted C6 to C20 arylene group, a substituted or unsubstituted C1 to C20 heteroarylene group, or a combination thereof,

[0032] M 1 to M 5 are each independently a single bond, -O-, -S-, -S(=O)-, -S(=O)2-, -C(=O)-, -(CO)O-, -O(CO)O-, -NR""- (wherein R"" is hydrogen, deuterium or C1 to C10 alkyl), or a combination thereof, and

[0033] * indicates the connection point.

[0034] A in Chemical Formula 2 to Chemical Formula 5 may be represented by at least one of the structures represented by Chemical Formula A-1 to Chemical Formula A-4:

[0035] [Chemical Formula A-1]

[0036]

[0037] [Chemical Formula A-2]

[0038]

[0039] [Chemical Formula A-3]

[0040]

[0041] [Chemical Formula A-4]

[0042]

[0043] In Chemical Formulas A-1 to A-4,

[0044] Rx may independently be hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, substituted or unsubstituted C1 to C10 heteroalkyl, substituted or unsubstituted C1 to C10 heteroalkenyl, substituted or unsubstituted C1 to C10 heteroalkynyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 heterocycloalkyl, substituted or unsubstituted C6 to C20 aryl, substituted or unsubstituted C1 to C20 heteroaryl, or a combination thereof, and

[0045] * indicates the connection point.

[0046] Ar1 of Chemical Formula 1 may be a group including a substituted or unsubstituted heterocyclic ring selected from Group 1.

[0047] [Clan 1]

[0048]

[0049]

[0050] In group 1,

[0051] Z, Z' and Z" are each independently N, O, S or P, and

[0052] “Substituted” may be replaced by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof.

[0053] Ar2 of Chemical Formula 1 may be a substituted or unsubstituted aromatic hydrocarbon group selected from Group 2.

[0054] [Clan 2]

[0055]

[0056] In group 2,

[0057] “Substituted” may be replaced by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof.

[0058] Ar1 of Chemical Formula 1 may be a group including a substituted or unsubstituted heterocyclic ring selected from Group 1-1.

[0059] [Clan 1-1]

[0060]

[0061] In group 1-1,

[0062] “Substituted” may be replaced by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof.

[0063] Ar2 of Chemical Formula 1 may be a substituted or unsubstituted aromatic hydrocarbon group selected from Group 2-1.

[0064] [Clan 2-1]

[0065]

[0066] In Group 2-1,

[0067] “Substituted” may be replaced by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof.

[0068] B1 and B2 of Chemical Formula 1 may each independently include a substituted or unsubstituted one selected from Group 3.

[0069] [Clan 3]

[0070]

[0071] In group 3,

[0072] “Substituted” may be replaced by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof.

[0073] The weight ratio of the polymer to the compound included in the resist underlayer composition according to an embodiment may be about 9:1 to about 1:9.

[0074] The weight average molecular weight (Mw) of the polymer may be from about 2,000 g / mole to about 300,000 g / mole.

[0075] The molecular weight of the compound can be from about 300 g / mole to about 5,000 g / mole.

[0076] The molecular weight of the compound can be from about 1,000 g / mole to about 50,000 g / mole.

[0077] The resist underlayer composition may further comprise one or more polymers selected from the group consisting of acrylic resins, epoxy resins, novolac resins, glycoluril-based resins, and melamine-based resins.

[0078] The resist underlayer composition may further include additives including a crosslinking agent, a thermal acid generator, a surfactant, a plasticizer, or a combination thereof.

[0079] According to another embodiment, a method for forming a pattern includes: forming an etching target layer on a substrate; applying an anti-etching base layer composition according to an embodiment to the etching target layer to form an anti-etching base layer; forming a photoresist pattern on the anti-etching base layer; and using the photoresist pattern as an etching mask to sequentially etch the anti-etching base layer and the etching target layer.

[0080] The forming of the resist underlayer may further include heat-treating the resist underlayer composition at a temperature of about 100° C. to about 500° C. after coating the resist underlayer composition.

[0081] The formation of the photoresist pattern may include forming a photoresist layer on the resist base layer, exposing the photoresist layer, and developing the photoresist layer.

[0082] The resist underlayer composition according to the embodiment does not cause a resist pattern to collapse even in a fine patterning process, is formed as a thin layer to shorten an etching process time, and improves patterning performance and efficiency by improving sensitivity to an exposure light source.

[0083] The resist underlayer composition according to the embodiment can provide a uniform resist underlayer without phase separation even when different materials are mixed.

[0084] Therefore, the resist underlayer composition according to the embodiment or the resist underlayer prepared therefrom may be advantageously used to form a fine pattern of a photoresist using a high energy light source such as EUV. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] Figures 1-6is a cross-sectional view for explaining a method of forming a pattern using the resist underlayer composition according to an embodiment.

[0086] Explanation of Figure Numbers

[0087] 100: substrate;

[0088] 102: thin layer;

[0089] 104: resist bottom layer;

[0090] 106: photoresist layer;

[0091] 106a: exposure area;

[0092] 106b: non-exposed area;

[0093] 108: photoresist pattern;

[0094] 110: mask;

[0095] 112: organic layer pattern;

[0096] 114: Thin layer pattern. DETAILED DESCRIPTION

[0097] Hereinafter, the embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the embodiments of the present invention. However, the present disclosure can be implemented in many different forms and should not be construed as being limited to the example embodiments set forth herein.

[0098] In the drawings, the thickness of layers, films, panels, regions, etc. may be exaggerated for clarity, and the same reference numerals denote the same elements throughout the specification. It should be understood that when an element, such as a layer, film, region, or substrate, is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present.

[0099] As used herein, "substituted" means that a hydrogen atom of a compound is replaced by a substituent selected from a halogen atom (F, Br, CI, or I), a hydroxyl group, an alkoxy group, a nitro group, a cyano group, an amino group, an azido group, a guanidino group, a hydrazine group, a hydrazono group, a carbonyl group, a carboxamide group, a thiol group, an ester group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a vinyl group, a Ci to C20 alkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C30 aryl group, a C7 to C30 aralkyl group, a Ci to C30 alkoxy group, a Ci to C20 heteroalkyl group, a C3 to C20 heteroarylalkyl group, a C3 to C30 cycloalkyl group, a C3 to C15 cycloalkenyl group, a C6 to C15 cycloalkynyl group, a C3 to C30 heterocycloalkyl group, and combinations thereof, when not otherwise provided.

[0100] Additionally, two adjacent substituents of a substituted halogen atom (F, Br, CI, or I), a hydroxyl group, a nitro group, a cyano group, an amino group, an azido group, a guanidino group, a hydrazine group, a hydrazono group, a carbonyl group, a carboxamide group, a thiol group, an ester group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a Ci to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C6 to C30 aryl group, a C7 to C30 aralkyl group, a Ci to C30 alkoxy group, a Ci to C20 heteroalkyl group, a C3 to C20 heteroarylalkyl group, a C3 to C30 cycloalkyl group, a C3 to C15 cycloalkenyl group, a C6 to C15 cycloalkynyl group, or a C2 to C30 heterocyclyl group can be fused to form a ring. For example, a substituted C6 to C30 aryl group can be fused with another adjacent substituted C6 to C30 aryl group to form a substituted or unsubstituted fluorene ring.

[0101] In this specification, when not otherwise provided, "aliphatic hydrocarbon group" includes "saturated aliphatic hydrocarbon group" and "unsaturated aliphatic hydrocarbon group".

[0102] "Saturated aliphatic hydrocarbon group" includes a functional group in which all bonds between carbons are single bonds, such as an alkyl group or an alkylene group. Additionally, "unsaturated aliphatic hydrocarbon group" refers to a functional group in which the bonds between carbons include one or more unsaturated bonds, and can include, for example, a double bond or a triple bond, such as an alkenyl group, an alkynyl group, an alkenylene group, or an alkynylene group.

[0103] As used herein, "aromatic hydrocarbon group" refers to a group having one or more hydrocarbon aromatic moieties, where the hydrocarbon aromatic moieties are connected by single bonds, and the hydrocarbon aromatic moieties are directly or indirectly fused with a non-aromatic fused ring, when not otherwise provided.

[0104] As used herein, "heterocyclyl" is a concept including heteroaryl, and can include at least one heteroatom selected from N, O, S, P, and Si, instead of carbon (C) in a cyclic compound such as aryl, cycloalkyl, a fused ring thereof, or a combination thereof. When the heterocyclyl is a fused ring, the entire ring or each ring of the heterocyclyl can include one or more heteroatoms.

[0105] More specifically, the substituted or unsubstituted aryl and / or the substituted or unsubstituted heterocyclyl can be a substituted or unsubstituted phenyl, a substituted or unsubstituted naphthyl, a substituted or unsubstituted anthryl, a substituted or unsubstituted phenanthryl, a substituted or unsubstituted tetracenyl, a substituted or unsubstituted pyrenyl, a substituted or unsubstituted biphenyl, a substituted or unsubstituted terphenyl, a substituted or unsubstituted quaterphenyl, a substituted or unsubstituted perylenyl, a substituted or unsubstituted indenyl, a substituted or unsubstituted furanyl, a substituted or unsubstituted thiophenyl, a substituted or unsubstituted pyrrolyl, a substituted or unsubstituted pyrazolyl, a substituted or unsubstituted imidazolyl, a substituted or unsubstituted triazolyl, a substituted or unsubstituted oxazolyl, a substituted or unsubstituted thiazolyl, a substituted or unsubstituted oxadiazolyl, a substituted or unsubstituted thiadiazolyl, a substituted or unsubstituted pyridyl, a substituted or unsubstituted pyrimidinyl, a substituted or unsubstituted pyrazinyl, a substituted or unsubstituted triazinyl, a substituted or unsubstituted benzofuranyl, a substituted or unsubstituted benzothiophenyl, a substituted or unsubstituted benzimidazolyl, a substituted or unsubstituted indolyl, a substituted or unsubstituted quinolyl, a substituted or unsubstituted isoquinolyl, a substituted or unsubstituted quinazolyl, a substituted or unsubstituted quinoxalyl, a substituted or unsubstituted naphthylidinyl, a substituted or unsubstituted benzoxazinyl, a substituted or unsubstituted benzothiazinyl, a substituted or unsubstituted acridinyl, a substituted or unsubstituted phenoxazinyl, a substituted or unsubstituted phenothiazinyl, a substituted or unsubstituted phenoxathiinyl, a substituted or unsubstituted fluorenyl, a substituted or unsubstituted dibenzofuranyl, a substituted or unsubstituted dibenzothiophenyl, a substituted or unsubstituted carbazolyl, pyridoindolyl, benzopyridinoxazinyl, benzopyridinonthiazinyl, 9,9-dimethyl-9,10-dihydroacridinyl, a combination thereof, or a combination of the aforementioned groups, but is not limited thereto. In one example of the present application, the heterocyclyl or heteroaryl can be a pyridyl, an indolyl, a carbazolyl, or a pyridoindolyl.

[0106] As used herein, the term "combination" refers to mixing or copolymerization, when a specific definition is not otherwise provided.

[0107] As used herein, polymer means to include oligomers and polymers.

[0108] Unless otherwise specified in the specification, the weight average molecular weight is measured by dissolving a powder sample in tetrahydrofuran (THF), and then using Agilent Technologies' 1200 series Gel Permeation Chromatography (GPC) (column: Shodex Company LF-804, standard sample: Shodex polystyrene).

[0109] In addition, unless otherwise defined in the specification, "*" indicates a point of attachment of a structural unit of a compound or a portion of a compound.

[0110] Lithography technology includes processes of forming a layer with a resist material on a substrate, selectively exposing it to a specific light source for forming a predetermined pattern thereon by using a mask, and developing it to form a pattern on the resist layer. On the other hand, the demand for reducing chip size is in an unceasing trend in the semiconductor industry. In response to this trend, the resist patterned in the lithography technology should have a line width reduced to tens of nanometers so that the formed pattern can be transferred to the underlying material in the lower substrate by an etching process. However, since the resist has a smaller pattern size, the height (aspect ratio) of the resist capable of withstanding the line width is limited, and thus can not have sufficient resistance during etching. In this regard, when the resist material needs a thinner, thicker substrate for etching or a deeper pattern, a resist underlayer has been used to compensate for these.

[0111] This resist underlayer serves as a second mask between the resist layer and the substrate for patterning, and thus should withstand the etching process required during pattern transfer. At the same time, the resist underlayer should be formed with a thinner thickness to shorten the exposure time in the etching process. Because the resist underlayer is thin, the resist underlayer is important for uniform coating, in which when two or more components having different properties from each other are included in the resist underlayer composition, there can be adverse phenomena such as phase separation, coating non-uniformity, etc. when forming an ultra-thin film.

[0112] The present inventors of the present application provide a uniform resist underlayer composition including two or more components having different properties from each other to maintain the advantageous effects of each component and solve the above problems such as phase separation, coating non-uniformity, etc. that occur due to the combination of different components, so that this composition exhibits all the excellent effects of each component, and it has been confirmed that the ultra-thin layer formed therefrom has excellent film density as well as high etching performance and sensitivity, thereby completing the present application.

[0113] Specifically, the resist underlayer composition according to the embodiment includes: a polymer including a main chain, a side chain, or a main chain and a side chain including a heterocyclic ring including two or more nitrogen atoms in the ring; a compound including a moiety represented by Chemical Formula 1; and a solvent.

[0114] The polymer included in the resist underlayer composition according to an embodiment may include any one or more of the structural units represented by Chemical Formulas 2 to 5.

[0115] [Chemical Formula 2]

[0116]

[0117] [Chemical Formula 3]

[0118]

[0119] [Chemical Formula 4]

[0120]

[0121] [Chemical Formula 5]

[0122]

[0123] In Chemical Formulas 2 to 5,

[0124] A is a heterocyclic ring containing two or more nitrogen atoms in the ring,

[0125] R a 、R b and R c each independently represents hydroxy, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, substituted or unsubstituted C1 to C10 heteroalkyl, substituted or unsubstituted C1 to C10 heteroalkenyl, substituted or unsubstituted C1 to C10 heteroalkynyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 heterocycloalkyl, substituted or unsubstituted C6 to C20 aryl, substituted or unsubstituted C1 to C20 heteroaryl, or a combination thereof,

[0126] L 1 To L 5 are each independently a single bond, a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C1 to C10 heteroalkylene group, a substituted or unsubstituted C3 to C20 cycloalkylene group, a substituted or unsubstituted C2 to C20 heterocycloalkylene group, a substituted or unsubstituted C6 to C20 arylene group, a substituted or unsubstituted C1 to C20 heteroarylene group, or a combination thereof,

[0127] M 1 to M 5 are each independently a single bond, -O-, -S-, -S(=O)-, -S(=O)2-, -C(=O)-, -(CO)O-, -O(CO)O-, -NR""- (wherein R"" is hydrogen, deuterium or C1 to C10 alkyl), or a combination thereof, and

[0128] * indicates the connection point.

[0129] In embodiments, “A” in Chemical Formula 2 and Chemical Formula 3 may be represented by at least one of the structures represented by Chemical Formula A-1 to Chemical Formula A-4.

[0130] [Chemical Formula A-1]

[0131]

[0132] [Chemical Formula A-2]

[0133]

[0134] [Chemical Formula A-3]

[0135]

[0136] [Chemical Formula A-4]

[0137]

[0138] In Chemical Formulas A-1 to A-4,

[0139] R x are independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, substituted or unsubstituted C1 to C10 heteroalkyl, substituted or unsubstituted C1 to C10 heteroalkenyl, substituted or unsubstituted C1 to C10 heteroalkynyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 heterocycloalkyl, substituted or unsubstituted C6 to C20 aryl, substituted or unsubstituted C1 to C20 heteroaryl, or a combination thereof, and

[0140] * indicates the connection point.

[0141] As described above, since A in the structural units represented by Chemical Formula 2 and Chemical Formula 3 of the polymer includes a heterocyclic ring containing two or more nitrogen atoms in the ring, the resist underlayer derived from the resist underlayer composition including the polymer can improve density.

[0142] In addition, Formulae A-1 to A-4 contain functional groups containing a triazine or isocyanurate backbone and a double bond to the triazine or isocyanurate backbone. Functional groups containing double bonds have high electron density because they are likely to be sp 2 -sp 2 The bond is bonded to the triazine or isocyanurate main chain, and thus it is possible to improve the density of the thin layer to implement a layer having a dense structure in the form of an ultra-thin layer, and improve light absorption efficiency during exposure of the resist underlying composition.

[0143] In addition, when the resist underlayer composition according to the embodiment is used to form a resist underlayer, secondary electrons can be additionally generated during the photoprocess, and the additionally generated secondary electrons can be transferred to the photoresist during the photoprocess to maximize the acid generation efficiency. Therefore, the sensitivity of the photoresist can be improved by increasing the photoprocessing speed of the photoresist.

[0144] In addition, etching selectivity is improved due to the triazine backbone, and energy efficiency can be improved when a pattern is formed after exposure to high-energy rays such as extreme ultraviolet (EUV; wavelength 13.5 nm) and electron beam (E-beam).

[0145] Meanwhile, the compound included in the resist underlayer composition according to the embodiment includes a moiety represented by Chemical Formula 1.

[0146] [Chemical Formula 1]

[0147]

[0148] In Chemical Formula 1,

[0149] Ar1 is a group containing a heterocyclic ring,

[0150] Ar2 is a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group,

[0151] B1 and B2 are each independently a single bond, a substituted or unsubstituted C1 to C10 aliphatic hydrocarbon group, a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, or a combination thereof,

[0152] X1 to X4 are each independently hydrogen, deuterium, a hydroxyl group, a thiol group, a cyano group, a substituted or unsubstituted amino group, a halogen atom, a substituted or unsubstituted C1 to C30 aliphatic hydrocarbon group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof, l, m, and n are each independently an integer from 0 to 5, and

[0153] o is an integer from 1 to 30.

[0154] In an embodiment, Ar1 of Chemical Formula 1 may include a substituted or unsubstituted heterocycle selected from Group 1.

[0155] [Clan 1]

[0156]

[0157]

[0158] In group 1,

[0159] Z, Z' and Z" are each independently N, O, S or P, and

[0160] The heterocycle selected from Group 1 may be substituted by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof.

[0161] In another embodiment, Ar1 in Chemical Formula 1 may include a substituted or unsubstituted heterocycle selected from Group 1-1.

[0162] [Clan 1-1]

[0163]

[0164] The group containing a heterocycle selected from Group 1-1 may be substituted with a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof. For example, it may be substituted with a hydroxyl group, a C1 to C30 alkyl group, or a C2 to C30 alkenyl group.

[0165] In one embodiment, Ar2 of Chemical Formula 1 may be a substituted or unsubstituted aromatic hydrocarbon group selected from Group 2.

[0166] [Clan 2]

[0167]

[0168] The aromatic hydrocarbon group selected from Group 2 may be substituted by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof. For example, it may be substituted by a hydroxyl group or a C1 to C10 alkoxy group.

[0169] In an embodiment, Ar2 of Chemical Formula 1 may be a substituted or unsubstituted aromatic hydrocarbon group selected from Group 2-1 among the substituted or unsubstituted aromatic hydrocarbon groups selected from Group 2.

[0170] [Clan 2-1]

[0171]

[0172] The aromatic hydrocarbon group selected from Group 2-1, such as Group 2, may be substituted by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof. For example, it may be substituted by a hydroxyl group or a C1 to C10 alkoxy group.

[0173] In one embodiment, B1 and B2 in Chemical Formula 1 may each independently include a substituted or unsubstituted one selected from Group 3.

[0174] [Clan 3]

[0175]

[0176] The cyclic compound selected from Group 3 may be substituted by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof.

[0177] In an embodiment, B1 and B2 of Chemical Formula 1 may be substituted or unsubstituted one selected from Group 3-1 among the substituted or unsubstituted aromatic hydrocarbon groups selected from Group 3.

[0178] [Clan 3-1]

[0179]

[0180] The cyclic compound selected from Group 3-1 in Group 3 may be substituted by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R" (wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof), a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof.

[0181] The weight ratio of the polymer to the compound included in the resist underlayer composition according to an embodiment may be about 9:1 to about 1:9. For example, the weight ratio may be about 8:2 to about 2:8, such as about 7:3 to about 3:7, such as about 6:4 to about 4:6, but is not limited thereto. In an embodiment, the weight ratio of the polymer to the compound may be about 9:1 to about 1:1, such as about 8:1 to about 1:1, such as about 7:1 to about 1:1, such as about 6:1 to about 1:1, such as about 5:1 to about 1:1, such as about 4:1 to about 1:1, or such as about 3:1 to about 1:1, but is not limited thereto.

[0182] By including the polymer and the compound in the composition within the above range, the thickness, surface roughness, and planarization degree of the resist underlayer can be controlled.

[0183] The polymer can have a weight average molecular weight of about 1,000 g / mole to about 300,000 g / mole. More specifically, the polymer can have a weight average molecular weight in the range of about 2,000 g / mole to about 300,000 g / mole, such as 2,000 g / mole to about 200,000 g / mole, such as about 2,000 g / mole to about 100,000 g / mole, such as about 2,000 g / mole to about 90,000 g / mole, such as about 2,000 g / mole to about 70,000 g / mole, such as about 2,000 g / mole to about 50,000 g / mole, such as about 2,000 g / mole to about 30,000 g / mole, such as about 2,000 g / mole to about 20,000 g / mole, or such as about 2,000 g / mole to about 10,000 g / mole, but is not limited thereto. By having a weight average molecular weight in the above range, the carbon content and solubility in a solvent of a resist underlayer composition containing the polymer can be adjusted and optimized.

[0184] The compound may be a monomolecular compound or an oligomer, and the molecular weight of the compound may be from about 300 g / mole to about 5,000 g / mole.

[0185] The compound can be a polymer, and the compound can have a molecular weight (weight average molecular weight) of about 1,000 g / mole to about 50,000 g / mole.

[0186] When the compound is a single molecule or an oligomer, the molecular weight of the compound may more specifically be about 300 g / mol to about 5,000 g / mol, for example, about 300 g / mol to about 3,000 g / mol, for example, about 500 g / mol to about 3,000 g / mol, for example, about 500 g / mol to about 2,000 g / mol, for example, about 500 g / mol to about 1,500 g / mol, and when the compound is a polymer, the weight average molecular weight of the compound may more specifically be about 1,000 g / mol to about 50,000 g / mol, for example, about 1,000 g / mol to about 30,000 g / mol, for example, about 1,000 g / mol to about 20,000 g / mol, or for example, about 1,000 g / mol to about 10,000 g / mol, but is not limited thereto. When the compound including the moiety represented by Chemical Formula 1 has a molecular weight or a weight average molecular weight within the above range, the prepared resist underlying film density may be improved, and thus damage or collapse of a photoresist pattern may be prevented during a patterning process.

[0187] The resist bottom layer composition according to an embodiment may include a solvent. The solvent is not particularly limited as long as it has enough solubility and / or dispersibility for the polymer and compound according to an embodiment. The solvent may include, for example, propylene glycol, propylene glycol diacetate, methoxypropylene glycol, diethylene glycol, diethylene glycol butyl ether, tri(ethylene glycol) monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, ethyl lactate, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, methylpyrrolidone (methylpyrrolidone), methylpyrrolidone (methylpyrrolidinone), 2-hydroxyisobutyric acid methyl ester, acetylacetone, 3-ethoxyethyl propionate or a combination thereof, but is not limited thereto.

[0188] The resist underlayer composition according to an embodiment may further include, in addition to the polymer, the compound, and the solvent, one or more polymers selected from the group consisting of acrylic resin, epoxy novolac resin, glycoluril-based resin, and melamine-based resin, but is not limited thereto.

[0189] The resist underlayer composition according to another embodiment may further include an additive. The additive includes a cross-linking agent, a thermal acid generator, a surfactant, a plasticizer, or a combination thereof, but is not limited thereto.

[0190] The crosslinking agent can be used to further harden the base layer by inducing a crosslinking reaction, and may include, for example, melamine-based, substituted urea-based, or polymer-based crosslinking agents. Preferably, the crosslinking agent may have at least two crosslinking substituents and may be, for example, a compound such as methoxymethylated glycoluril, butoxymethylated glycoluril, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, methoxymethylated thiourea, or butoxymethylated thiourea, but the present disclosure is not limited thereto.

[0191] As the crosslinking agent, a crosslinking agent having high heat resistance can be used, and for example, a compound containing a crosslinking substituent having an aromatic ring (eg, a benzene ring or a naphthalene ring) in the molecule can be used. The crosslinking agent can have, for example, two or more crosslinking sites.

[0192] The thermal acid generator may be, for example, an acidic compound, such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium p-toluenesulfonate, salicylic acid, sulfosalicylic acid, citric acid, benzoic acid, hydroxybenzoic acid, naphthalenecarbonic acid, etc. or / and 2-nitrobenzyl toluenesulfonate, other organic alkyl sulfonates, etc., but is not limited thereto.

[0193] When forming the resist underlayer, the surfactant may be used to improve coating defects caused by an increase in solid content, and may be, for example, alkylbenzenesulfonate, alkylpyridinium salt, polyethylene glycol, quaternary ammonium salt, but the present disclosure is not limited thereto.

[0194] The plasticizer is not particularly limited, and various known plasticizers can be used. Examples of the plasticizer may include low molecular weight compounds such as phthalates, adipates, phosphates, trimellitates, citrates, etc., polyether compounds, polyester-based compounds, polyacetal compounds, etc.

[0195] The additive may be included in an amount of about 0.001 parts by weight to 40 parts by weight based on 100 parts by weight of the resist underlayer composition. Within the above range, solubility may be improved without changing optical properties of the resist underlayer composition.

[0196] According to another embodiment, a resist underlayer manufactured using the resist underlayer composition is provided. The resist underlayer may be in a form obtained by coating the resist underlayer composition on a substrate and then curing the composition through a heat treatment process.

[0197] In the following, reference Figures 1-6 A method for forming a pattern using the aforementioned resist underlayer composition is described.

[0198] Figures 1-6 A cross-sectional view for explaining a method of forming a pattern using the resist underlayer composition according to an embodiment.

[0199] First, referring to Figure 1 , a subject to be etched is prepared. An example of the subject to be etched can be a thin layer 102 formed on a semiconductor substrate 100. Hereinafter, a case where the subject to be etched is the thin layer 102 will be described. The surface of the thin layer 102 is washed to remove impurities and the like remaining thereon. The thin layer 102 can be, for example, a silicon nitride layer, a polysilicon layer, or a silicon oxide layer.

[0200] Subsequently, on the surface of the washed thin layer 102, the aforementioned resist underlayer composition can be applied by a spin coating method.

[0201] Next, the applied composition is dried and baking is performed to form a resist underlayer 104 on the thin layer. The baking can be performed at about 100°C to about 500°C, for example, about 100°C to about 300°C. In particular, the resist underlayer composition is described in detail above and thus will be omitted.

[0202] Referring to Figure 2 , a photoresist layer 106 is formed by applying a photoresist on the resist underlayer 104.

[0203] An example of the photoresist can be a positive photoresist containing a diazorezoquinone compound and a novolak resin; a chemically amplified positive photoresist including an acid generator capable of dissociating an acid after exposure, a compound having an increased solubility in an aqueous alkali solution by decomposition in the presence of the acid, and an alkali-soluble resin; or a chemically amplified positive photoresist including an acid generator and an alkali-soluble resin having a group capable of imparting a resin having an increased solubility in an aqueous alkali solution by decomposition in the presence of the acid.

[0204] Next, the substrate 100 having the photoresist layer 106 is subjected to a primary baking. The primary baking can be performed at about 90°C to about 120°C.

[0205] Referring to Figure 3 , the photoresist layer 106 can be selectively exposed.

[0206] The exposure of the photoresist layer 106 can be performed, for example, by placing an exposure mask having a predetermined pattern on a mask stage of an exposure apparatus and aligning the exposure mask 110 on the photoresist layer 106. Then, by irradiating light into the exposure mask 110, predetermined regions of the photoresist layer 106 formed on the substrate 100 are selectively reacted with the light passing through the exposure mask.

[0207] Examples of the light used during the exposure can include i-line active radiation having a wavelength of 365 nm, a KrF excimer laser having a wavelength of 248 nm, and a short wavelength light such as an ArF excimer laser having a wavelength of 193 nm, and in addition, an extreme ultraviolet (EUV) light having a wavelength of 13.5 nm corresponding to an extreme ultraviolet light can be used, for example.

[0208] The exposed portion of the photoresist layer 106a is relatively hydrophilic compared to the unexposed portion of the photoresist layer 106b. Therefore, the exposed region 106a and the unexposed region 106b of the photoresist layer 106 may have different solubilities.

[0209] Next, the substrate 100 is secondarily baked. The second baking may be performed at about 90° C. to about 150° C. Due to the second baking, the exposed region of the photoresist layer becomes easily soluble with respect to a specific solvent.

[0210] refer to Figure 4 Specifically, the photoresist layer corresponding to the exposure area 106 a is dissolved and removed by using tetramethyl ammonium hydroxide (TMAH) or the like, and the photoresist layer 106 b remaining after development forms a photoresist pattern 108 .

[0211] Next, the photoresist pattern 108 is used as an etching mask to etch the resist bottom layer 104. Figure 5 The organic layer pattern 112 shown in FIG. 1 is formed by the etching process described above. The etching process may be, for example, dry etching using an etching gas such as CHF3, CF4, Cl2, O2, or a mixture thereof. As described above, since the resist underlayer formed using the resist underlayer composition according to the embodiment has a fast etching rate, a smooth etching process can be performed in a short time.

[0212] refer to Figure 6 , the exposed thin layer 102 is etched by applying the photoresist pattern 108 as an etching mask. As a result, the thin layer forms a thin layer pattern 114. In the exposure process performed above, the width of the thin layer pattern 114 formed by the exposure process using a short-wavelength light source such as activating radiation i-line (wavelength 365 nanometers), KrF excimer laser (wavelength 248 nanometers), or ArF excimer laser (wavelength 193 nanometers) can be several tens of nanometers to several hundreds of nanometers, and the width of the thin layer pattern 114 formed by the exposure process using an EUV light source can be less than or equal to about 20 nanometers.

[0213] Hereinafter, the present invention will be described in more detail with reference to examples of polymer synthesis and preparation of a resist underlayer composition containing the same. However, the present invention is not limited to the following examples.

[0214] Synthesis Example

[0215] Synthesis Example A1

[0216] 20 grams of 1,3-diallyl-5-(2-hydroxyethyl) isocyanurate, 6.7 grams of 1,2-ethanedithiol, 1.3 grams of azobisisobutyronitrile (AIBN) and 40 grams of N,N-dimethylformamide (DMF) were placed in a 500 ml 2-neck round bottle, and a condenser was connected thereto. After reacting at 60 ° C for 16 hours, the reaction solution was cooled to room temperature (23 ° C). The reaction solution was added dropwise to a 1-liter wide-mouth bottle containing 800 grams of water while stirring to form a colloid, and the colloid was dissolved in 80 grams of tetrahydrofuran (THF). The dissolved resin solution was treated with toluene to form a precipitate, and unimolecular compounds and small molecules were removed. Finally, 15 grams of a polymer represented by chemical formula 3a (weight average molecular weight (Mw) = 7,500 grams / mole) were obtained.

[0217] [Chemical Formula 3a]

[0218]

[0219] Synthesis Example A2

[0220] 24.9 grams of 1,3,5-triallyl-1,3,5-triazine-2,4,6-trione, 7.4 grams of 3-mercaptopropanol, 0.7 grams of azobisisobutyronitrile (AIBN) and 48 grams of N,N-dimethylformamide (DMF) were placed in a 500 ml 3-neck round bottle, and a condenser was connected to it. After reacting at 80 ° C for 16 hours, the reaction solution was cooled to room temperature. The reaction solution was added dropwise to a 1-liter wide-mouth bottle containing 800 grams of water while stirring to produce a jelly, and the jelly was dissolved in 80 grams of tetrahydrofuran (THF). The dissolved resin solution was treated with toluene to form a precipitate, and unimolecular compounds and small molecules were removed. Finally, 10 grams of a polymer represented by Chemical Formula 4a (weight average molecular weight (Mw) = 10,500 grams / mole) were obtained.

[0221] [Chemical Formula 4a]

[0222]

[0223] Synthesis Example A3

[0224] 148.6 g (0.5 mol) of 1,3,5-isocyanuric acid triglycidyl ester, 60.0 g (0.4 mol) of 2,2'-thiodiacetic acid, 9.1 g of benzyltriethylammonium chloride, and 350 g of N,N-dimethylformamide were placed in a 1-liter 2-necked round flask, and a condenser was attached thereto. After increasing the temperature to 100°C, the mixture was reacted for 8 hours and cooled to room temperature (23°C). Subsequently, the reaction solution was transferred to a 1-liter wide-mouthed flask, and then washed three times with hexane, and then washed with purified water. The obtained jelly-like resin was completely dissolved in 80 g of THF, and then slowly added dropwise to 700 g of toluene. Then, the solvent was removed therefrom to obtain a polymer (Mw = 9,100 g / mol) containing the structural unit represented by Chemical Formula 5a.

[0225] [Chemical Formula 5a]

[0226]

[0227] Synthesis Example B1

[0228] 24 grams of 1,4-phthaloyl chloride, 50 grams of 9-vinyl-9H-carbazole and 200 grams of 1,2-dichloroethane are placed in a flask. 34 grams of aluminum chloride are slowly added to this solution and then stirred at room temperature for 6 hours. When the reaction is complete, the precipitate formed by adding methanol thereto is filtered and dried to obtain an intermediate compound. Subsequently, 50 grams of the intermediate compound and 200 grams of tetrahydrofuran are added to the flask, and 25 grams of sodium borohydride aqueous solution are slowly added thereto, and then stirred at room temperature for 24 hours. When the reaction is complete, the compound therefrom is neutralized to a pH of about 7 by using a 2% aqueous hydrochloric acid solution, and then extracted and dried with ethyl acetate to obtain a compound represented by Chemical Formula 1a.

[0229] [Chemical Formula 1a]

[0230]

[0231] Synthesis Example B2

[0232] In a 500 ml 2-neck flask equipped with a mechanical stirrer and a cooling tube, 20 grams of 1,1,2-trimethyl-1H-benzindole, 10.6 grams of 10-hydroxyphenanthrene-9-carboxaldehyde, 8.6 grams of 9-fluorenone and 4.9 grams of p-toluenesulfonic acid were added to 51 grams of 1,4-dioxane, and then fully stirred, heated to 110 ° C, and stirred again for 14 hours. When the reaction was complete, the internal temperature of the flask was reduced to 65 ° C and 200 grams of THF were added thereto. The pH of the resultant was adjusted to about 5 by using a 7% sodium bicarbonate aqueous solution. Subsequently, 1000 milliliters of ethyl acetate was poured therein, and then kept stirring and filtered with a separatory funnel to extract the organic layer separately. Then, 500 milliliters of water were added to the separatory funnel, and then shaken to remove the remaining acid and sodium salt, repeated three times and more times, and the organic layer was finally extracted. Subsequently, the organic solution was concentrated using an evaporator, and 700 g of THF was added to the obtained compound to obtain a compound in a solution state. The solution was slowly added dropwise to a beaker containing 3000 ml of hexane to form a precipitate, and the solvent was removed therefrom to obtain a compound (Mw = 1,540 g / mol) containing each of the structural units represented by Chemical Formula 1b and Chemical Formula 1c.

[0233] [Chemical Formula 1b]

[0234]

[0235] [Chemical Formula 1c]

[0236]

[0237] Synthesis Example B3

[0238] 10 g of benzothiophene, 10.7 g of 2-naphthol, 40 g of (E)-1,2-bis(4-(methoxymethyl)phenyl)ethylene, 18 g of diethyl sulfate, and 15 g of propylene glycol monomethyletheracetate (PGMEA) were placed in a flask and then stirred at 110° C. for 8 hours. When the reaction was completed, the resultant was added to 200 g of hexane for precipitation, and the precipitate was filtered by adding methanol and water thereto and then treated with methanol to remove the remaining monomers, thereby obtaining a compound containing each of the structural units represented by Chemical Formula 1d and Chemical Formula 1e (Mw=3,520 g / mol).

[0239] [Chemical Formula 1d]

[0240]

[0241] [Chemical Formula 1e]

[0242]

[0243] Synthesis Example B4

[0244] 20 g of thianthrene, 13.3 g of 2-naphthol, 5.6 g of p-formaldehyde, 1.9 g of p-toluenesulfonic acid, and 50 g of PGMEA were placed in a flask and then stirred at 70° C. for 8 hours. When the reaction was completed, the resultant was added to 200 g of hexane for precipitation, and the precipitate was filtered by adding methanol and water thereto, and then treated with methanol to remove the remaining monomers, thereby obtaining a compound containing the structural unit represented by Chemical Formula 1f (Mw = 4,050 g / mol).

[0245] [Chemical Formula 1f]

[0246]

[0247] Preparation of resist base composition

[0248] Examples 1 to 7 and Comparative Examples 1 to 2

[0249] 0.5 g of each polymer (or compound) according to Synthesis Examples 1 to 7, 0.125 g of PD1174 (hardener; Tokyo Chemical Industry (TCI)), and 0.01 g of pyridinium para-toluenesulfonate (PPTS) were completely dissolved in a mixed solvent of propylene glycol monomethyl ether and ethyl lactate (mixing volume ratio = 7:3) at the ratios shown in Table 1 to prepare resist underlayer compositions according to Examples 1 to 7 and Comparative Examples 1 to 2, respectively.

[0250] [Table 1]

[0251] Polymer Compound Ratio Example 1 Synthesis Example Al Synthesis Example Bl 6:4 Example 2 Synthesis Example Al Synthesis Example B2 7:3 Example 3 Synthesis Example Al Synthesis Example B4 8:2 Example 4 Synthesis Example A2 Synthesis Example Bl 7:3 Example 5 Synthesis Example A2 Synthesis Example B2 6:4 Example 6 Synthesis Example A2 Synthesis Example B3 7:3 Example 7 Synthesis Example A3 Synthesis Example B4 7:3 Comparative Example 1 Synthesis Example Al - - Comparative Example 2 - Synthesis Example B2 -

[0252] Etching resistance evaluation

[0253] 2 ml of each of the compositions according to Example 1 and Example 5 and Comparative Examples 1 and 2 were cast on an 8-inch wafer, spin-coated at a main speed of 1,500 rpm for 20 seconds using an automatic track (ACT-8, Tokyo Electron Limited; TEL), and cured at 210°C for 90 seconds to form a thin layer with a thickness of 50 angstroms.

[0254] Subsequently, the formed thin layer was dry-etched under CF4, CHF3 and O2 gas for 20 seconds, and then the etching rate was measured relative to the etched thickness to show the relative etching rate. Table 2 shows the results obtained by calculating the relative etching rate of the examples or comparative examples when the etching rate of comparative example 1 is 1.

[0255] [Table 2]

[0256] Etch Rate (Angstroms / second) Example 1 0.8 Example 5 0.8 Comparative Example 1 1 Comparative Example 2 0.6

[0257] Referring to Table 2, the underlayer formed of the resist underlayer composition according to Example 1 or Example 5, respectively, becomes sufficiently etch-resistant to the etching gas.

[0258] Coating uniformity evaluation

[0259] 2 ml of each of the compositions according to Examples 1 to 7 and Comparative Examples 1 to 2 was applied on an 8-inch wafer, spin-coated at a main speed of 1,500 rpm for 20 seconds using an automatic track (ACT-8, Tokyo Electron Co., Ltd. (TEL)), and cured at 210° C. for 90 seconds to form a thin layer having a thickness of 50 angstroms.

[0260] Each thickness at 51 points along the horizontal axis was measured to evaluate coating uniformity, and the results are shown in Table 3.

[0261] [Table 3]

[0262] Coating Uniformity (Min / Max Range) Example 1 1.8 Angstroms Example 2 1.3 Angstroms Example 3 1.2 Angstroms Example 4 2.0 Angstroms Example 5 1.4 Angstroms Example 6 1.0 Angstroms Example 7 2.8 Angstroms Comparative Example 1 7.3 Angstroms Comparative Example 2 5.7 Angstroms

[0263] Referring to Table 3, the resist underlayer compositions according to Examples 1 to 7 exhibited excellent coating uniformity, compared with the resist underlayer composition according to the comparative example.

[0264] Film density evaluation

[0265] The resist underlayer compositions according to Examples 1 to 7 and Comparative Examples 1 to 2 were respectively applied on a silicon substrate by spin coating and heat-treated on a hot plate at 210° C. for 90 seconds to form a resist underlayer having a thickness of 100 nm.

[0266] Then, the resist underlayer was measured with respect to density, and the results are shown in Table 4. The density of the resist underlayer was measured by using an X-ray diffractometer (model: X'Pert PRO MPD, Malvern Panalytical Ltd. (Netherlands)).

[0267] [Table 4]

[0268] Film Density (g / cc) Example 1 1.42 Example 2 1.38 Example 3 1.40 Example 4 1.39 Example 5 1.38 Example 6 1.40 Example 7 1.36 Comparative Example 1 1.31 Comparative Example 2 1.35

[0269] Referring to Table 4, the films formed from the resist underlayer compositions according to Examples 1 to 7 exhibited higher density than the film formed from the resist underlayer composition according to the comparative example. It is estimated that the film density is increased by including a polymer including a heterocyclic ring containing two or more nitrogen atoms in the ring and a compound including a heterocyclic group and an aromatic hydrocarbon group.

[0270] Referring to the results of Table 4, the resist underlayer compositions according to Examples 1 to 7 were formed into films having a denser structure as compared with the film according to the comparative example.

[0271] In the above, certain embodiments of the present invention have been described and illustrated. However, it will be apparent to those skilled in the art that the present invention is not limited to the embodiments as described, and that various modifications and conversions may be made without departing from the spirit and scope of the present invention. Therefore, the modified or converted embodiments may not be understood solely from the technical concepts and aspects of the present invention, and the modified embodiments are within the scope of the claims of the present invention.

Claims

1. A resist base composition comprising: A polymer comprising a main chain, a side chain, or a main chain and a side chain comprising a heterocyclic ring containing two or more nitrogen atoms in the ring, wherein the polymer comprises any one or more of the structural units represented by Chemical Formula 2 to Chemical Formula 5; A compound comprising a moiety represented by Chemical Formula 1; as well as solvents, wherein the molecular weight of the compound is from 1,000 g / mol to 50,000 g / mol, The weight ratio of the polymer to the compound is 9:1 to 1:9: [Chemical Formula 1] Wherein, in Chemical Formula 1, Ar1 is a group containing a heterocyclic ring, Ar2 is a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, B1 and B2 are each independently a single bond, a substituted or unsubstituted C1 to C10 aliphatic hydrocarbon group, a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, or a combination thereof, X1 to X4 are each independently hydrogen, deuterium, a hydroxyl group, a thiol group, a cyano group, a substituted or unsubstituted amino group, a halogen atom, a substituted or unsubstituted C1 to C30 aliphatic hydrocarbon group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof, l, m and n are each independently an integer from 0 to 5, and o is an integer from 1 to 30, [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] Among them, in Chemical Formula 2 to Chemical Formula 5, A is a heterocyclic ring containing two or more nitrogen atoms in the ring, R a 、R b and R c each independently represents hydroxy, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, substituted or unsubstituted C1 to C10 heteroalkyl, substituted or unsubstituted C1 to C10 heteroalkenyl, substituted or unsubstituted C1 to C10 heteroalkynyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 heterocycloalkyl, substituted or unsubstituted C6 to C20 aryl, substituted or unsubstituted C1 to C20 heteroaryl, or a combination thereof, L 1 to L 5 are each independently a single bond, a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C1 to C10 heteroalkylene group, a substituted or unsubstituted C3 to C20 cycloalkylene group, a substituted or unsubstituted C2 to C20 heterocycloalkylene group, a substituted or unsubstituted C6 to C20 arylene group, a substituted or unsubstituted C1 to C20 heteroarylene group, or a combination thereof, L 6 is an unsubstituted C1 alkylene group, M 1 to M 5 are each independently a single bond, -O-, -S-, -S(=O)-, -S(=O)2-, -C(=O)-, -(CO)O-, -O(CO)O-, -NR""-, or a combination thereof, wherein R"" is hydrogen, deuterium, or C1 to C10 alkyl, and * indicates the connection point.

2. The resist underlayer composition according to claim 1, wherein A of Chemical Formula 2 to Chemical Formula 5 is represented by at least one of the structures represented by Chemical Formula A-1 to Chemical Formula A-4: [Chemical Formula A-1] [Chemical Formula A-2] [Chemical Formula A-3] [Chemical Formula A-4] in, In Chemical Formulas A-1 to A-4, R x are each independently hydrogen, substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, substituted or unsubstituted C1 to C10 heteroalkyl, substituted or unsubstituted C1 to C10 heteroalkenyl, substituted or unsubstituted C1 to C10 heteroalkynyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 heterocycloalkyl, substituted or unsubstituted C6 to C20 aryl, substituted or unsubstituted C1 to C20 heteroaryl, or a combination thereof, and * indicates the connection point.

3. The resist underlayer composition according to claim 1, wherein Ar1 of Chemical Formula 1 is a group comprising a substituted or unsubstituted heterocyclic ring selected from Group 1: [Clan 1] in, In group 1, Z, Z' and Z" are each independently N, O, S or P, and The “substituted” refers to replacement by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C3 to C30 cycloalkenyl group, NR'R", a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof, wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof.

4. The resist underlayer composition according to claim 1, wherein Ar2 in Chemical Formula 1 is a substituted or unsubstituted aromatic hydrocarbon group selected from Group 2: [Clan 2] in, In group 2, The “substituted” refers to replacement by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R", a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group, or a combination thereof, wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group, or a combination thereof.

5. The resist underlayer composition according to claim 1, wherein Ar1 of Chemical Formula 1 is a group comprising a substituted or unsubstituted heterocyclic ring selected from Group 1-1: [Clan 1-1] 6. The resist underlayer composition according to claim 5, wherein The substitution is replacement by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C3 to C30 cycloalkenyl group, NR'R", a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group or a combination thereof, wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group or a combination thereof.

7. The resist underlayer composition according to claim 1, wherein Ar2 of Chemical Formula 1 is a substituted or unsubstituted aromatic hydrocarbon group selected from Group 2-1: [Clan 2-1] 8. The resist underlayer composition according to claim 7, wherein The substitution is replacement by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R", a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group or a combination thereof, wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group or a combination thereof.

9. The resist underlayer composition according to claim 1, wherein B1 and B2 in Chemical Formula 1 each independently comprise a substituted or unsubstituted one selected from Group 3: [Clan 3] 10. The resist underlayer composition according to claim 9, wherein The substitution is replacement by a hydroxyl group, a C1 to C10 alkoxy group, a cyano group, a halogen atom, a C3 to C30 cycloalkenyl group, NR'R", a C1 to C20 heteroalkyl group, a C2 to C30 heterocycloalkyl group, a C2 to C30 heteroaryl group or a combination thereof, wherein R' and R" are each independently hydrogen, a C1 to C10 alkyl group, a C6 to C20 aryl group or a combination thereof.

11. The resist underlayer composition according to claim 1, wherein The weight average molecular weight of the polymer is 2,000 g / mol to 300,000 g / mol.

12. The resist underlayer composition according to claim 1, wherein The molecular weight of the compound is 300 g / mol to 5,000 g / mol.

13. The resist underlayer composition according to claim 1, wherein The resist underlayer composition further includes one or more polymers selected from the group consisting of acrylic resin, epoxy resin, novolac resin, glycoluril-based resin, and melamine-based resin.

14. The resist underlayer composition according to claim 1, wherein The resist underlayer composition further includes additives including a crosslinking agent, a thermal acid generator, a surfactant, a plasticizer, or a combination thereof.

15. A method for forming a pattern, comprising: forming an etching target layer on the substrate, applying the resist underlayer composition according to any one of claims 1 to 14 onto the etching target layer to form a resist underlayer, forming a photoresist pattern on the resist bottom layer, and The resist bottom layer and the etching target layer are sequentially etched using the photoresist pattern as an etching mask.

16. The method according to claim 15, wherein The forming of the resist underlayer further includes heat-treating the resist underlayer composition at a temperature of 100° C. to 500° C. after coating the resist underlayer composition.

17. The method according to claim 15, wherein The forming of the photoresist pattern includes: forming a photoresist layer on the resist bottom layer, exposing the photoresist layer, and The photoresist layer is developed.

Images