JP4627536B2 - Compound, negative resist composition and pattern forming method - Google Patents

Description

  The present invention relates to a compound suitable for a negative resist composition, an intermediate compound thereof, a negative resist composition, and a resist pattern forming method.

  In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization has been rapidly progressing due to advances in lithography technology.

As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, conventionally, ultraviolet rays typified by g-line and i-line have been used, but at present, mass production of semiconductor elements using a KrF excimer laser or an ArF excimer laser has started. In addition, studies have been made on F ₂ excimer lasers, electron beams, EUV (extreme ultraviolet rays), X-rays, and the like having shorter wavelengths than these excimer lasers.

  Further, as one of pattern forming materials capable of forming a pattern with fine dimensions, a chemically amplified resist containing a base material component having a film forming ability and an acid generator component that generates an acid upon exposure is known. ing. Chemically amplified resists include a negative type in which alkali solubility is reduced by exposure and a positive type in which alkali solubility is increased by exposure.

  Conventionally, a polymer has been used as a base material component of such a chemically amplified resist. For example, a PHS system such as polyhydroxystyrene (PHS) or a resin in which a part of its hydroxyl group is protected with an acid dissociable, dissolution inhibiting group. Resins, copolymers derived from (meth) acrylic acid esters, resins in which a part of the carboxy group is protected with an acid dissociable, dissolution inhibiting group, and the like are used.

  However, when a pattern is formed using such a pattern forming material, there is a problem that roughness is generated on the upper surface of the pattern or the surface of the side wall. For example, the roughness of the resist pattern side wall surface, that is, the line edge roughness (LER) causes distortion around the hole in the hole pattern, variation in the line width in the line and space pattern, and the like. May cause adverse effects.

  Such a problem becomes more serious as the pattern size is smaller. Therefore, for example, lithography using electron beams or EUV aims to form a fine pattern of several tens of nanometers, and therefore extremely low roughness exceeding the current pattern roughness is required.

  However, a polymer generally used as a substrate has a large molecular size (average square radius per molecule) of around several nm. In the development process of pattern formation, the dissolution behavior of the resist with respect to the developing solution is usually performed in units of one molecular component of the base material. Therefore, as long as a polymer is used as the base material component, further reduction in roughness is extremely difficult.

  In order to solve such a problem, a resist using a low molecular material as a base material component has been proposed as a material aiming for extremely low roughness. For example, Non-Patent Documents 1 and 2 propose low molecular weight materials having an alkali-soluble group such as a hydroxyl group or a carboxy group, part or all of which are protected with an acid dissociable, dissolution inhibiting group. Patent Document 1 proposes a negative pattern forming method using a compound containing a γ-hydroxycarboxylic acid structure or a δ-hydroxycarboxylic acid structure.

Japanese Patent Laid-Open No. 11-109627 T.A. Hirayama, D.H. Shiono, H .; Hada and J.H. Onodera: J.M. Photopolym. Sci. Technol. 17 (2004), p. 435 Jim-Baek Kim, Hyo-Jin Yun, Young-Gil Kwon: Chemistry Letters (2002), p. 1064-1065

  The low molecular weight material as the resist base component as described above is expected to be able to reduce roughness due to its low molecular weight and thus small molecular size. Therefore, there is an increasing demand for new low molecular weight materials that can be used for resist compositions.

  However, the conventional negative polarity conversion has a problem that the resist sensitivity is insufficient in the low molecular resist material.

  The present invention has been made in view of the above circumstances, and provides a negative resist composition capable of simultaneously achieving high sensitivity, high resolution, and low LER, and a resist pattern forming method using the negative resist composition The purpose is to do.

The negative resist composition of the present invention is composed of two groups of components: a base component (A) and an acid generator component (B) that generates an acid upon irradiation with radiation.
The first aspect of the present invention includes a compound represented by the following general formula (S-1) having a functional group that is chemically converted by the action of an acid and has reduced solubility in an alkaline developer, and a general formula (I- A negative resist composition comprising a base material component (A) composed of an additive compound represented by 1) and an acid generator component (B) that generates an acid upon irradiation with radiation. is there.

[In Formula (S-1), Z ¹ , Z ² , Z ³ , Z ⁴ , Z ⁵ and Z ⁶ each independently have a hydrogen atom or a hydroxycarboxylic acid which is opened by hydrolyzing a lactone ring. Wherein R ^{11 to} R ¹⁷ are each independently an alkyl group, an alkenyl group or an aromatic hydrocarbon group having 1 to 10 carbon atoms, and the structure thereof May contain a hetero atom; ga, gb, gc, gd, j are each independently an integer of 1 or more, k, q are 0 or an integer of 1 or more, and (ga + j + k + q), (gb + j + k + q) , (Gc + j + k + q), and (gd + j + k + q) are 5 or less; h is an integer of 1 or more, l and m are each independently 0 or an integer of 1 or more, and h + l + m is 4 or less; i An integer of 1 or more, n, o are each independently 0 or an integer of 1 or more, and i + n + o is 4 or less; X is an alkylene group, an aliphatic cyclic group or an aromatic cyclic group. ]

[In Formula (I-1), Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ are each independently a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group or an aromatic hydrocarbon group, a group having the lactone ring, alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group are present 0 to 4 per molecule,; R ²¹ ~ R ²⁷ is each independently an alkyl group, alkenyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms and may contain a hetero atom in the structure thereof; ge, gf, gg, gh and j2 are each independently And k2 and q2 are 0 or an integer of 1 or more, and (ge + j2 + k2 + q2), (gf + j2 + k2 + q2), (gg + j2 + k2 + q2), and (gh + j2 + k) + Q2) is 5 or less; h2 is an integer of 1 or more, l2, m2 are each independently 0 or an integer of 1 or more, and h2 + l2 + m2 is 4 or less; i2 is an integer of 1 or more; n2 and o2 are each independently 0 or an integer of 1 or more, and i2 + n2 + o2 is 4 or less; X is an alkylene group, an aliphatic cyclic group, or an aromatic cyclic group. ]
In the second aspect of the present invention, the compound having a functional group that is chemically converted by the action of an acid in the substrate component (A) and has reduced solubility in an alkali developer is represented by the general formula (S-2). A negative resist composition, characterized by comprising:

[In Formula (S-2), Z ¹ , Z ² , Z ³ , Z ⁴ , Z ⁵ and Z ⁶ each independently have a hydrogen atom or a hydroxycarboxylic acid which is opened by hydrolyzing a lactone ring. And at least one hydroxycarboxylic acid is present per molecule; R ³¹ and R ³² are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, X may be an alkylene group, an aliphatic cyclic group or an aromatic cyclic group. ]
In the third aspect of the present invention, a compound having a functional group that is chemically converted by the action of an acid in the substrate component (A) and has reduced solubility in an alkaline developer is represented by the general formula (S-3). A negative resist composition, characterized by comprising:

[In the formula (S-3), Z is a group having a hydroxycarboxylic acid that is opened by hydrolysis of a lactone ring; R ^{51 to} R ⁵⁷ are each independently an alkyl group having 1 to 10 carbon atoms, alkenyl A group or an aromatic hydrocarbon group which may contain a hetero atom in the structure; ga, gb, gc, gd and j are each independently an integer of 1 or more, and k and q are 0 or 1 (Ga + j + k + q), (gb + j + k + q), (gc + j + k + q), and (gd + j + k + q) are 5 or less; h is an integer of 1 or more, and l and m are each independently 0 or 1 or more Is an integer, and h + 1 + m is 4 or less; i is an integer of 1 or more, n and o are each independently 0 or an integer of 1 or more, and i + n + o is 4 or less; X is Alkylene group, an aliphatic cyclic group or an aromatic cyclic group. ]
In the fourth aspect of the present invention, a compound having a functional group which is chemically converted by the action of an acid and has reduced solubility in an alkaline developer in the substrate component (A) is represented by the general formula (S-4). A negative resist composition, characterized by comprising:

[In Formula (S-4), Z is a group having a hydroxycarboxylic acid that is opened by hydrolysis of a lactone ring; R ⁷¹ and R ⁷² are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic group; A hydrocarbon group which may contain heteroatoms in its structure; X is an alkylene group, an aliphatic cyclic group or an aromatic cyclic group; ]
A fifth aspect of the present invention is a negative resist composition, wherein the additive compound in the substrate component (A) is a compound represented by the general formula (I-2).

[In formula (I-2), Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ are each independently a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, or an alkenyl group. Or an aromatic hydrocarbon group, the group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group is present in an amount of 0 to 4 per molecule; R ⁴¹ , R ⁴² Each independently represents an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure; X represents an alkylene group, an aliphatic cyclic group or an aromatic cyclic group; is there. ]
A sixth aspect of the present invention is a negative resist composition, wherein the additive compound in the substrate component (A) is a compound represented by the general formula (I-3).

[In Formula (I-3), Y represents a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group; R ^{61 to} R ⁶⁷ are each independently An alkyl group, an alkenyl group or an aromatic hydrocarbon group having 1 to 10 carbon atoms, which may contain a hetero atom in the structure thereof; ge, gf, gg, gh and j2 are each independently an integer of 1 or more K2, q2 is 0 or an integer of 1 or more, and (ge + j2 + k2 + q2), (gf + j2 + k2 + q2), (gg + j2 + k2 + q2), and (gh + j2 + k2 + q2) are 5 or less; h2 is an integer of 1 or more, l2, m2 Are each independently an integer of 0 or 1 and h2 + l2 + m2 is 4 or less; i2 is an integer of 1 or more, and n2 and o2 are Independently 0 or an integer of 1 or more is, and i2 + n2 + o2 is 4 or less; X is an alkylene group, an aliphatic cyclic group or an aromatic cyclic group. ]
A seventh aspect of the present invention is a negative resist composition, wherein the additive compound in the substrate component (A) is a compound represented by the general formula (I-4).

[In Formula (I-4), Y is a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group or an aromatic hydrocarbon group; R ⁸¹ and R ⁸² are each independently An alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group which may contain a hetero atom in the structure; X is an alkylene group, an aliphatic cyclic group or an aromatic cyclic group; ]
According to an eighth aspect of the present invention, there is provided a step of forming a resist film on a substrate using the negative resist composition of the first to seventh aspects, a step of exposing the resist film, and developing the resist film And a resist pattern forming method including a step of forming a resist pattern.

  Here, the “alkyl group” in the claims and the specification includes linear, branched and cyclic monovalent saturated hydrocarbon groups unless otherwise specified.

  Unless otherwise specified, the “alkenyl group” includes linear, branched and cyclic monovalent unsaturated hydrocarbon groups having one double bond.

  The “alkylene group” includes a divalent saturated hydrocarbon group having 1 or 2 carbon atoms unless otherwise specified.

  “Aliphatic” is a relative concept with respect to aromatics, and is defined to mean groups, compounds, etc. that do not have aromaticity. The “aliphatic cyclic group” means a monocyclic group or polycyclic group having no aromaticity.

  The “aromatic cyclic group” means a cyclic group having aromaticity. The “aromatic cyclic group” indicates a monocyclic group or polycyclic group having aromaticity.

  “Exposure” is a concept that includes general irradiation of radiation.

  INDUSTRIAL APPLICABILITY According to the present invention, a negative resist composition and a resist pattern forming method using the negative resist composition that can simultaneously achieve high sensitivity, high resolution, and low LER are provided.

The negative resist composition of the present invention comprises a substrate component (A) and an acid generator component (B) that generates an acid upon irradiation with radiation.
≪Base material component (A) ≫
The compound having a functional group which is chemically converted by the action of an acid and has reduced solubility in an alkaline developer according to the first aspect of the present invention is represented by the above general formula (S-1).

  The compounds having a functional group which is chemically converted by the action of an acid and has reduced solubility in an alkaline developer according to the second to fourth aspects of the present invention are represented by the general formulas (S-2) and (S-3), respectively. ) And (S-4).

  In the above formulas (S-1), (S-2), (S-3), and (S-4), Z is a group having a hydroxycarboxylic acid opened by hydrolysis of a lactone ring. Examples of the group having a hydroxycarboxylic acid include a group having a hydroxycarboxylic acid which is opened by hydrolyzing the lactone ring from the same group having a lactone ring as described above. That is, it may be a group having a hydroxycarboxylic acid that is opened by hydrolysis of a lactone ring from a lactone-containing monocyclic group, or a hydroxycarboxylic acid that is opened by hydrolysis of a lactone ring from a lactone-containing polycyclic group. It may be a group having an acid.

  As the group having a hydroxycarboxylic acid that has been opened by hydrolysis of a lactone ring from a lactone-containing monocyclic group, a group represented by the following formula (Z-1-10) is preferable.

[In the formula (Z-1-10), p is an integer of 1 or more. ]
The group having a hydroxycarboxylic acid that has been opened by hydrolysis of the lactone ring is preferably a group having a γ-hydroxycarboxylic acid or a group having a δ-hydroxycarboxylic acid. These hydroxycarboxylic acids can easily form a 5-membered ring or a 6-membered ring by intramolecular esterification by acid-catalyzed reaction. Specifically, examples of the group having a hydroxycarboxylic acid opened by hydrolysis of a lactone ring from a lactone-containing monocyclic group include the following formula (Z-1-11) in the above formula (Z-1-10). The group having a hydroxycarboxylic acid represented by (p = 2) or the group having a hydroxycarboxylic acid represented by the following formula (Z-1-12) (p = 3) is preferable.

The number of hydroxycarboxylic acids that have been opened by hydrolysis of the lactone ring, per molecule of the compounds (S-1) and (S-2), is preferably 1 to 6, more preferably 1 to 4, One to two is particularly preferred.
In the above formulas (S-1) and (S-3), it is particularly preferable that ga = gb = gc = gd = h = i = 1.

R ^{11 to} R ¹⁷ , R ^{31 to} R ³² , R ^{51 to} R ⁵⁷ , and R ^{71 to} R ⁷² are each independently a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, 1 carbon atom 10 to 10 linear, branched or cyclic alkenyl groups, or an aromatic hydrocarbon group having 1 to 10 carbon atoms.
As the alkyl group, a linear or branched lower alkyl group having 1 to 5 or a cyclic alkyl group having 5 to 6 carbon atoms is preferable. Examples of the lower alkyl group include linear or branched alkyl such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl. Group, and among these, a methyl group is preferable. Examples of the cyclic alkyl group include a cyclohexyl group and a cyclopentyl group.

  The alkenyl group is preferably a linear, branched or cyclic alkenyl group having 2 to 6 carbon atoms, such as vinyl, 1-propenyl, allyl, isopropenyl, 1-butenyl, 2-butenyl, 2-pentenyl and cyclohexenyl. Etc. are more preferable, and vinyl and isopropenyl are particularly preferable.

The aromatic hydrocarbon group preferably has 6 to 15 carbon atoms, and examples thereof include a phenyl group, a tolyl group, a xylyl group, a mesityl group, a phenethyl group, and a naphthyl group.
These alkyl groups, alkenyl groups, and aromatic hydrocarbon groups may contain heteroatoms such as oxygen atoms, nitrogen atoms, and sulfur atoms in the structure.

ga, gb, gc, gd, j are each independently an integer of 1 or more, preferably 1-2, k and q are each independently 0 or 1 or more, preferably an integer not exceeding 2, and ( (ga + j + k + q), (gb + j + k + q), (gc + j + k + q), and (gd + j + k + q) are 5 or less.
h is an integer of 1 or more, preferably 1 to 2, l and m are each independently 0 or 1 or more, preferably an integer not exceeding 2, and h + 1 + m is 4 or less.
i is an integer of 1 or more, preferably 1 to 2, n and o are each independently 0 or 1 or more, preferably an integer not exceeding 2, and i + n + o is 4 or less.
X is an alkylene group, a divalent aliphatic cyclic group or a divalent aromatic cyclic group.
The alkylene group for X is preferably an alkylene group having 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, still more preferably a methylene group, an ethylene group, or a propylene group, and a methylene group Most preferably.

  The divalent aliphatic cyclic group for X may or may not have a substituent. Examples of the substituent include a lower alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated lower alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, an oxygen atom (= O), and the like.

The basic ring structure of the aliphatic cyclic group excluding substituents is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated.
A polycyclic group is preferred.

Specific examples of such aliphatic cyclic groups include groups in which two or more hydrogen atoms have been removed from a monocycloalkane; two or more hydrogens from a polycycloalkane such as a bicycloalkane, tricycloalkane, or tetracycloalkane. Examples include groups other than atoms. Specifically, a group obtained by removing two or more hydrogen atoms from a monocycloalkane such as cyclopentane or cyclohexane, or two or more polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom.
In these groups, some or all of the hydrogen atoms may be substituted with a substituent (for example, a lower alkyl group, a fluorine atom or a fluorinated alkyl group).
Among these, an aliphatic cyclic group having 4 to 15 carbon atoms is preferable, a group obtained by removing two hydrogen atoms from adamantane is more preferable, and in particular, a group obtained by removing the 1st and 3rd hydrogen atoms of adamantane. Is preferred.

  Examples of the divalent aromatic cyclic group for X include groups in which two hydrogen atoms have been removed from an aromatic compound such as benzene, naphthalene, anthracene, phenanthrene, and pyrene.

  As the compound (S-1), a compound represented by the following general formula (S-2) is particularly preferable because of excellent effects of the present invention.

[In Formula (S-2), Z ¹ , Z ² , Z ³ , Z ⁴ , Z ⁵ and Z ⁶ each independently have a hydrogen atom or a hydroxycarboxylic acid which is opened by hydrolyzing a lactone ring. And at least one hydroxycarboxylic acid is present per molecule; R ³¹ and R ³² are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, X may be an alkylene group, an aliphatic cyclic group or an aromatic cyclic group. ]
The bonding position of ^R 31, R3 ² in the formula (S-2), the following formula (S-2-1), the formula (S-2-2) is preferable.

As the bonding positions of R ⁷¹ , R ⁷² and OZ in formula (S-4), the following formula (S-4-2) and formula (S-4-3) are preferable.

  The compound used as an additive component of the negative resist composition of the present invention is represented by the above general formula (I-1).

[In Formula (I-1), Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ are each independently a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group or an aromatic hydrocarbon group, a group having the lactone ring, alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group are present 0 to 4 per molecule,; R ²¹ ~ R ²⁷ is each independently an alkyl group, alkenyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms, and may contain a hetero atom in the structure thereof; ge, gf, gg and gh are each independently Is an integer greater than or equal to 1, k2, q2 is 0 or an integer greater than or equal to 1, and (ge + j2 + k2 + q2), (gf + j2 + k2 + q2), (gg + j2 + k2 + q2), and (gh + j2 + k2 +) 2) is 5 or less; h2 is an integer of 1 or more, l2 and m2 are each independently 0 or an integer of 1 or more, and h2 + l2 + m2 is 4 or less; i2 is an integer of 1 or more; n2 and o2 are each independently 0 or an integer of 1 or more, and i2 + n2 + o2 is 4 or less; X is an alkylene group, an aliphatic cyclic group, or an aromatic cyclic group. ]
Moreover, an additive component is represented by the said general formula (I-2), (I-3), and (I-4).

[In formula (I-2), Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ are each independently a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, or an alkenyl group. Or an aromatic hydrocarbon group, the group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group is present in an amount of 0 to 4 per molecule; R ⁴¹ , R ⁴² Each independently represents an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure; X represents an alkylene group, an aliphatic cyclic group or an aromatic cyclic group; is there. ]

[In Formula (I-3), Y represents a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group; R ^{61 to} R ⁶⁷ are each independently An alkyl group, an alkenyl group or an aromatic hydrocarbon group having 1 to 10 carbon atoms, which may contain a hetero atom in the structure thereof; ge, gf, gg, gh and j2 are each independently an integer of 1 or more K2, q2 is 0 or an integer of 1 or more, and (ge + j2 + k2 + q2), (gf + j2 + k2 + q2), (gg + j2 + k2 + q2), and (gh + j2 + k2 + q2) are 5 or less; h2 is an integer of 1 or more, l2, m2 Are each independently an integer of 0 or 1 and h2 + l2 + m2 is 4 or less; i2 is an integer of 1 or more, and n2 and o2 are Independently 0 or an integer of 1 or more is, and i2 + n2 + o2 is 4 or less; X is an alkylene group, an aliphatic cyclic group or an aromatic cyclic group. ]

[In Formula (I-4), Y is a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group or an aromatic hydrocarbon group; R ⁸¹ and R ⁸² are each independently An alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group which may contain a hetero atom in the structure; X is an alkylene group, an aliphatic cyclic group or an aromatic cyclic group; ]
As the lactone-containing monocyclic group, a group represented by the following formula (Y-1-10) is preferable.

[In formula (Y-1-10), p is an integer of 1-3. ]
Specifically, the lactone-containing monocyclic group is preferably a group obtained by removing one hydrogen atom from γ-butyrolactone, or a group obtained by removing one hydrogen atom from δ-valerolactone, which is easy to synthesize. From the above points, each is represented by the following formula (Y-1-11) or the following formula (Y-1-12) except for one hydrogen atom bonded to the α-position carbon of γ-butyrolactone or δ-valerolactone. More preferred are the groups

R ^{21 to} R ²⁷ , R ^{41 to} R ⁴² , R ^{61 to} R ⁶⁷ , R ^{81 to} R ⁸² of the compounds (I-1), (I-2), (I-3), and (I-4) are Each independently a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, a linear, branched or cyclic alkenyl group having 1 to 10 carbon atoms, or an aromatic group having 1 to 10 carbon atoms. It is a hydrocarbon group.

  As the alkyl group, a linear or branched lower alkyl group having 1 to 5 or a cyclic alkyl group having 5 to 6 carbon atoms is preferable. Examples of the lower alkyl group include linear or branched alkyl such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, and neopentyl. Group, and among these, a methyl group is preferable. Examples of the cyclic alkyl group include a cyclohexyl group and a cyclopentyl group.

  The alkenyl group is preferably a linear, branched or cyclic alkenyl group having 2 to 6 carbon atoms, such as vinyl, 1-propenyl, allyl, isopropenyl, 1-butenyl, 2-butenyl, 2-pentenyl and cyclohexenyl. Etc. are more preferable, and vinyl and isopropenyl are particularly preferable.

  The aromatic hydrocarbon group preferably has 6 to 15 carbon atoms, and examples thereof include a phenyl group, a tolyl group, a xylyl group, a mesityl group, a phenethyl group, and a naphthyl group.

  These alkyl groups, alkenyl groups, and aromatic hydrocarbon groups may contain heteroatoms such as oxygen atoms, nitrogen atoms, and sulfur atoms in the structure.

  ge, gf, gg, and gh are each independently an integer of 1 or more, preferably an integer of 1 to 2, k2, q2 are each independently 0 or 1 or more, preferably an integer not exceeding 2, and (Ge + j2 + k2 + q2), (gf + j2 + k2 + q2), (gg + j2 + k2 + q2), and (gh + j2 + k2 + q2) are 5 or less.

h is an integer of 1 or more, preferably 1 to 2, l and m are each independently 0 or 1 or more, preferably an integer not exceeding 2, and h + 1 + m is 4 or less.
i is an integer of 1 or more, preferably 1 to 2, n and o are each independently 0 or 1 or more, preferably an integer not exceeding 2, and i + n + o is 4 or less.

  Compound (I-1) has (h + i) Y (a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group) per molecule. Regarding Y, the proportion of hydrogen atoms and groups other than hydrogen atoms in one molecule is preferably 2 or more, more preferably 4 or more.

Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ in compound (I-2), Y of (I-3), and (I-4) (a group having a hydrogen atom or a lactone ring, carbon As for the number 1-20 alkyl group, alkenyl group or aromatic hydrocarbon group), the ratio of hydrogen atoms to groups other than hydrogen atoms in one molecule is preferably 2 or more hydrogen atoms. Preferably, it is 4 or more.
X is an alkylene group, a divalent aliphatic cyclic group or a divalent aromatic cyclic group.
The alkylene group for X is preferably an alkylene group having 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, still more preferably a methylene group, an ethylene group, or a propylene group, and a methylene group Most preferably.

The divalent aliphatic cyclic group for X may or may not have a substituent. Examples of the substituent include a lower alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated lower alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, an oxygen atom (= O), and the like.
The basic ring structure of the aliphatic cyclic group excluding substituents is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated.
A polycyclic group is preferred.

  Specific examples of such aliphatic cyclic groups include groups in which two or more hydrogen atoms have been removed from a monocycloalkane; two or more hydrogens from a polycycloalkane such as a bicycloalkane, tricycloalkane, or tetracycloalkane. Examples include groups other than atoms. Specifically, a group obtained by removing two or more hydrogen atoms from a monocycloalkane such as cyclopentane or cyclohexane, or two or more polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom.

In these groups, some or all of the hydrogen atoms may be substituted with a substituent (for example, a lower alkyl group, a fluorine atom or a fluorinated alkyl group).
Among these, an aliphatic cyclic group having 4 to 15 carbon atoms is preferable, a group obtained by removing two hydrogen atoms from adamantane is more preferable, and in particular, a group obtained by removing the 1st and 3rd hydrogen atoms of adamantane. Is preferred.

Examples of the divalent aromatic cyclic group for X include groups in which two hydrogen atoms have been removed from an aromatic compound such as benzene, naphthalene, anthracene, phenanthrene, and pyrene.
As the bonding positions of R ⁴¹ and R ⁴² in formula (I-2), the following formulas (I-2-1) and (I-2-2) are preferable.

As the bonding positions of R ⁸¹ , R ⁸² and OY in the formula (I-4), the following formulas (I-4-1) and (I-4-2) are preferable.

<Method for Producing Compound (I-1) (I-2)>
Compound (I-1) (I-2) is, for example, an etherification reaction of a compound represented by the following general formula (I-1-A) with a halide such as an alkyl halide or a halogenated lactone. It can manufacture by performing reaction of these. When all Y are hydrogen atoms, the compound (I-1-A) can be used.

<Production Method of Compound (I-3) (I-4)>
Compound (I-3) (I-4) includes, for example, a compound represented by the following general formula (J-3) (hereinafter referred to as compound (J-3)) and a phenol compound having a substituent (described below). Formula (J-3-2)) can be obtained by dehydration condensation under acidic conditions. Four molecules of a phenol compound (hereinafter referred to as compound (J-3-2)) represented by the following formula (J-3-2) are dehydrated and condensed with respect to two formyl groups of compound (J-3). To do.

  Specifically, the compound (J-3) is dissolved in an organic solvent (for example, a mixed solvent of methanol-THF (tetrahydrofuran)), and the phenol compound represented by the above formula (J-3-2) (hereinafter, compound) (J-3-2)) and an acid such as hydrochloric acid can be added to the solution.

  Compound (J-3) is, for example, a bissalicylaldehyde derivative formed by bonding two salicylaldehydes (which may have a substituent) via the X (following formula (J-3-3) ) Is reacted with a halide such as alkyl halide or halogenated lactone, and the hydroxyl group is substituted with Y. In the following formula (J-3-1), R13 to R16, h2, 12, m2, i2, n2, o2, and X are R13 to R16, h2, 12, and m2 in the above formula (I-3). , I2, n2, o2, and X.

  Examples of the halogenated lactone compound include brominated lactone compounds and chlorinated lactone compounds. A brominated lactone compound is preferred because of excellent reactivity. A compound represented by the following formula (J-3-10) can be exemplified.

[In the formula (J-1-10), p is an integer of 1 or more. ]
As the halogenated lactone compound represented by the above formula (J-3-10), a compound when p = 2, that is, α-bromo-γ-butyrolactone, or a compound when p = 3, that is, α-Bromo-δ-valerolactone is preferred.
<Production Method of Compound (S-1) (S-2)>
The manufacturing method of compound (S-1) (S-2) is based on manufacture of the said compound (I-1) (I-2). That is, for example, the compound represented by the general formula (I-1-A) is subjected to an alkali hydrolysis reaction after an etherification reaction using a halogenated lactone represented by the above (J-3-10). By doing so, it can be produced by converting the lactone ring to the corresponding hydroxycarboxylic acid.
<Method for Producing Compound (S-3) (S-4)>
The manufacturing method of compound (S-3) (S-4) is based on manufacture of the said compound (I-3) (I-4). That is, after dehydrating and condensing the compound (J-3) and a phenol compound having a substituent having a lactone ring (the following formula (J-3-2)) under acidic conditions, the lactone ring is hydrolyzed. Can be obtained by conversion to the corresponding carboxylic acid. Four molecules of the compound (J-3-2) undergo dehydration condensation on the two formyl groups of the compound (J-3).

  Specifically, the compound (J-3) is dissolved in an organic solvent (for example, a mixed solvent of methanol-THF (tetrahydrofuran)), and the phenol compound represented by the above formula (J-3-2) (hereinafter, compound) (J-3-2)) and an acid such as hydrochloric acid can be added to the solution.

Compound (J-3) is, for example, a bissalicylaldehyde derivative formed by bonding two salicylaldehydes (which may have a substituent) via the X (following formula (J-3-3) ) Is reacted with a halide such as alkyl halide or halogenated lactone, and the hydroxyl group is substituted with Y. Note that R ^{63 to} R ⁶⁶ , h2, l2, m2, i2, n2, o2, and X in the following formula (J-3-1) are R ^{13 to} R1 ⁶ and h2 in the formula (I-3). , L2, m2, i2, n2, o2, and X.

  Examples of the halogenated lactone compound include brominated lactone compounds and chlorinated lactone compounds. A brominated lactone compound is preferred because of excellent reactivity. A compound represented by the following formula (J-3-10) can be exemplified.

[In the formula (J-1-10), p is an integer of 1 or more. ]
As the halogenated lactone compound represented by the above formula (J-3-10), a compound when p = 2, that is, α-bromo-γ-butyrolactone, or a compound when p = 3, that is, α-Bromo-δ-valerolactone is preferred.

  The hydrolysis reaction of the lactone ring can be carried out using a hydroxide of a quaternary ammonium salt such as sodium hydroxide, potassium hydroxide, sodium carbonate, tetramethylammonium hydroxide.

  In the compounds (S-1), (S-2), (S-3), and (S-4), among the additive components ((I-1), (I-2), (I-3), and (I-4) When the acid generated from the acid generator component (B) is acted upon by exposure to the acid generator component (B) that generates an acid upon exposure to the resist composition, Hydroxycarboxylic acid changes to a lactone ring, and the entire compound (A-1) changes from alkali-soluble to alkali-insoluble.

  Therefore, the compounds (S-1), (S-2), (S-3), and (S-4) have additive components ((I-1) (I-2) ( I-3) Compound selected from (I-4)) Base component (A) that changes from alkali-soluble to alkali-insoluble by the action of acid, and acid generator component (B) that generates acid upon exposure In the negative resist composition containing, it can be suitably used as the substrate component (A).

By using a negative resist composition containing the compounds (S-1), (S-2), (S-3), and (S-4), a high-resolution resist pattern, for example, an ultrafine pattern having a pattern size of 100 nm or less A resist pattern can be formed.
This is presumed to be due to the uniformity of the molecular size of the compounds (S-1), (S-2), (S-3), and (S-4).

However, the compounds (S-1), (S-2), (S-3), and (S-4) are low molecular weight compounds having a carboxyl group that is excellent in solubility promotion in an alkaline aqueous solution such as an alkaline developer. In the production of semiconductor devices, when development is performed using a standard developer such as an aqueous 0.26N tetramethylammonium hydroxide solution, the development speed may be too high. Further, depending on the combination of the molecular skeleton structure and the carboxyl group, the development speed in a standard developer may be too slow.
Furthermore, since the carboxyl group is very polar, the roughness of the resist pattern may increase due to the interaction between the carboxyl groups depending on the combination of the molecular skeleton structure and the carboxyl group.
The roles of the additive components (I-1), (I-2), (I-3), and (I-4) are the compounds (S-1) (S-2) (S-3) (S- When used together with 4), the development speed of the resist is adjusted and the roughness of the resist pattern is reduced.

  This is because additive components (I-1), (I-2), (I-3) and (I-4) do not have a carboxyl group in the molecule, and compound (S-1) (S- 2) Since it has a molecular skeleton highly similar to (S-3) and (S-4), it is possible to form a resist coating film having substantially the same molecular size and uniformly mixed with each other. The relative difference in molecular diameter is within 25% between Group I compounds and Group S compounds.

That is, the first action of the compounds (I-1), (I-2), (I-3), and (I-4) is to moderate excessive dissolution promotion properties with respect to the alkaline developer having a carboxyl group, It leads to the development speed. Here, the appropriate development rate is such that the dissolution rate of the resist film in the developer is desirably 2 nm / s to 100 nm / s, and more desirably 5 nm / s to 50 nm / s.
The second effect is to alleviate excessive interaction between carboxyl groups such as hydrogen bonds, and to reduce the roughness of the resist pattern. Regarding the second action, the addition of a basic organic compound that is easily coordinated to an acidic carboxyl group is also effective, and a higher effect can be obtained by using the composition of the present invention in combination with the basic compound.
≪Negative resist composition≫
The negative resist composition of the present invention comprises the base material component (A) (hereinafter sometimes referred to as (A) component) and an acid generator component (B) that generates acid upon irradiation with radiation (hereinafter referred to as ( B) component)).
<(A) component>
In the component (A), when an acid generated from the component (B) acts upon exposure, the hydroxycarboxylic acid changes to a lactone ring, whereby the entire component (A) changes from alkali-soluble to alkali-insoluble. Therefore, in the formation of a resist pattern, when a resist film made of the resist composition is selectively exposed or heated after exposure in addition to exposure, the exposed portion turns into alkali-insoluble while the unexposed portion remains alkali-soluble. Since it does not change, a negative resist pattern can be formed by alkali development.

In the negative resist composition of the present invention, the component (A) needs to contain the compound (S-1) of the present invention.
A compound (S-1) may be used individually by 1 type, and may use 2 or more types together.
In the component (A), the ratio of the compound (S-1) is preferably more than 40% by mass, and more preferably more than 50% by mass.
The proportion of the compound (S-1) in the component (A) can be measured by means such as reverse phase chromatography.

Moreover, in the negative resist composition of this invention, (A) component needs to contain the said compound (I-1) of this invention.
Compound (I-1) may be used alone or in combination of two or more.
In the component (A), the ratio of the compound (I-1) is preferably less than 50% by mass.
The proportion of compound (I-1) in component (A) can be measured by means such as reverse phase chromatography.
The component (A) may further contain any resin component that has been proposed as a base material component of the chemically amplified resist layer so far as the effects of the present invention are not impaired.

  Examples of such resin components include those proposed as base resins such as conventional chemically amplified negative resist compositions for KrF and negative resist compositions for ArF. It can be appropriately selected according to the type.

In the negative resist composition of the present invention, the content of the component (A) may be adjusted according to the resist film thickness to be formed.
<(B) component>
The component (B) is not particularly limited, and those that have been proposed as acid generators for chemically amplified resists can be used. Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, poly (bissulfonyl) diazomethanes, and the like. There are various known diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like.

  Examples of the onium salt acid generator include an acid generator represented by the following general formula (b-0).

[Wherein R ¹⁵¹ represents a linear, branched or cyclic alkyl group, or a linear, branched or cyclic fluorinated alkyl group; R ¹⁵² represents a hydrogen atom, a hydroxyl group, a halogen atom, linear or A branched alkyl group, a linear or branched alkyl halide group, or a linear or branched alkoxy group; R ¹⁵³ is an optionally substituted aryl group; u "Is an integer from 1 to 3.]
In General Formula (b-0), R ¹⁵¹ represents a linear, branched, or cyclic alkyl group, or a linear, branched, or cyclic fluorinated alkyl group.

The linear or branched alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.
The cyclic alkyl group preferably has 4 to 12 carbon atoms, more preferably 5 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms.
The fluorinated alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.

  Further, the fluorination rate of the fluorinated alkyl group (ratio of the number of substituted fluorine atoms to the total number of hydrogen atoms in the alkyl group) is preferably 10 to 100%, more preferably 50 to 100%. Those in which all hydrogen atoms are substituted with fluorine atoms are preferred because the strength of the acid is increased.

R ¹⁵¹ is most preferably a linear alkyl group or a fluorinated alkyl group.

R ¹⁵² is a hydrogen atom, a hydroxyl group, a halogen atom, a linear or branched alkyl group, a linear or branched alkyl halide group, or a linear or branched alkoxy group.

In R ¹⁵² , examples of the halogen atom include a fluorine atom, a bromine atom, a chlorine atom, and an iodine atom, and a fluorine atom is preferable.

In R ¹⁵² , the alkyl group is linear or branched, and the carbon number thereof is preferably 1 to 5, particularly 1 to 4, and more preferably 1 to 3.

In R ¹⁵² , the halogenated alkyl group is a group in which part or all of the hydrogen atoms in the alkyl group are substituted with halogen atoms. Examples of the alkyl group here are the same as the “alkyl group” in R ¹⁵² . Examples of the halogen atom to be substituted include the same as those described above for the “halogen atom”. In the halogenated alkyl group, it is desirable that 50 to 100% of the total number of hydrogen atoms are substituted with halogen atoms, and it is more preferable that all are substituted.

In R ¹⁵² , the alkoxy group is linear or branched, and the carbon number thereof is preferably 1 to 5, particularly 1 to 4, and more preferably 1 to 3.

Among these, R ¹⁵² is preferably a hydrogen atom.

R ¹⁵³ is an aryl group which may have a substituent, and examples of the structure of the basic ring (matrix ring) excluding the substituent include a naphthyl group, a phenyl group, an anthracenyl group, and the like. From the viewpoint of absorption of exposure light such as ArF excimer laser, a phenyl group is desirable.

  Examples of the substituent include a hydroxyl group and a lower alkyl group (straight or branched chain, preferably having 5 or less carbon atoms, particularly preferably a methyl group).

As the aryl group for R ^153, an aryl group having no substituent is more preferable.

  u ″ is an integer of 1 to 3, preferably 2 or 3, and particularly preferably 3.

  Preferable examples of the acid generator represented by the general formula (b-0) include the following.

  Moreover, as an onium salt type acid generator other than the acid generator represented by general formula (b-0), the compound represented by the following general formula (b-1) or (b-2) is mentioned, for example. .

[Wherein, R ^{1 ″ to} R ^{3 ″} and R ^{5 ″ to} R ^{6 ″} each independently represents an aryl group or an alkyl group; R ^{4 ″} represents a linear, branched or cyclic alkyl group or fluorinated group. Represents an alkyl group; at least one of R ^{1 ″ to} R ^{3 ″} represents an aryl group, and at least one of R ^{5 ″ to} R ^{6 ″} represents an aryl group.]
In formula (b-1), R ^{1 ″ to} R ^{3 ″} each independently represents an aryl group or an alkyl group. At least one of R ^{1 ″ to} R ^{3 ″} represents an aryl group. Of R ^{1 ″ to} R ^{3 ″} , two or more are preferably aryl groups, and most preferably R ^{1 ″ to} R ^{3 ″} are all aryl groups.

The aryl group for R ^{1 ″ to} R ^{3 ″} is not particularly limited, and is, for example, an aryl group having 6 to 20 carbon atoms, in which part or all of the hydrogen atoms are alkyl groups, alkoxy groups It may or may not be substituted with a group, a halogen atom or the like. The aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenyl group and a naphthyl group.

The alkyl group that may be substituted for the hydrogen atom of the aryl group is preferably an alkyl group having 1 to 5 carbon atoms, and is a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group. Is most preferred.
The alkoxy group that may be substituted with a hydrogen atom of the aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and most preferably a methoxy group or an ethoxy group.
The halogen atom that may be substituted for the hydrogen atom of the aryl group is preferably a fluorine atom.

There is no restriction | limiting in particular as an alkyl group of R1 ^" -R3 ^" , For example, a C1-C10 linear, branched or cyclic alkyl group etc. are mentioned. It is preferable that it is C1-C5 from the point which is excellent in resolution. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decanyl group. A methyl group is preferable because it is excellent in resolution and can be synthesized at low cost.

Among these, R ^{1 ″ to} R ^{3 ″} are most preferably a phenyl group or a naphthyl group, respectively.

R ^{4 ″} represents a linear, branched or cyclic alkyl group or a fluorinated alkyl group.

The linear or branched alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.
The cyclic alkyl group is a cyclic group as indicated by R ^{1 ″} and preferably has 4 to 15 carbon atoms, more preferably 4 to 10 carbon atoms, and more preferably 6 carbon atoms. Most preferably, it is -10.

The fluorinated alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms. The fluorination rate of the fluorinated alkyl group (ratio of fluorine atoms in the alkyl group) is preferably 10 to 100%, more preferably 50 to 100%. Particularly, all the hydrogen atoms are substituted with fluorine atoms. It is preferable because the strength of the acid is increased.
R4 ″ is most preferably a linear or cyclic alkyl group or a fluorinated alkyl group.
In formula (b-2), R ^{5 ″ to} R ^{6 ″} each independently represents an aryl group or an alkyl group. At least one of R ^{5 ″ to} R ^{6 ″} represents an aryl group. All of R ^{5 ″ to} R ^{6 ″} are preferably aryl groups.
As the aryl group for R ^{5 ″ to} R ^{6 ″, the same as} the aryl groups for R ^{1 ″ to} R ^{3 ″} can be used.
As the alkyl group for R ^{5 ″ to} R ^{6 ″, the same as} the alkyl group for R ^{1 ″ to} R ^{3 ″} can be used.

Among these, it is most preferable that all of R ^{5 ″ to} R ^{6 ″} are phenyl groups.

^{"As R 4} in the formula ^{(b-1)" R 4} in the In the formula (b-2) include the same as.

  Specific examples of the onium salt acid generators represented by formulas (b-1) and (b-2) include diphenyliodonium trifluoromethanesulfonate or nonafluorobutanesulfonate, bis (4-tert-butylphenyl) iodonium. Trifluoromethanesulfonate or nonafluorobutanesulfonate, triphenylsulfonium trifluoromethanesulfonate, heptafluoropropanesulfonate or nonafluorobutanesulfonate, tri (4-methylphenyl) sulfonium trifluoromethanesulfonate, heptafluoropropanesulfonate or the same Nonafluorobutanesulfonate, dimethyl (4-hydroxynaphthyl) sulfonium trifluoromethanesulfonate, its heptaful Lopropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of monophenyldimethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of diphenylmonomethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate (4-methylphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate , Trifluoromethanesulfonate of tri (4-tert-butyl) phenylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of diphenyl (1- (4-methoxy) naphthyl) sulfonium, its heptafluoropropane Sulfonate or its nonafluorobutane sulfonate, di (1-naphthyl) phenylsulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate. In addition, onium salts in which the anion portion of these onium salts is replaced with methanesulfonate, n-propanesulfonate, n-butanesulfonate, or n-octanesulfonate can also be used.

  In addition, in the general formula (b-1) or (b-2), an onium salt-based acid generator in which the anion moiety is replaced with an anion moiety represented by the following general formula (b-3) or (b-4). Can also be used (the cation moiety is the same as (b-1) or (b-2)).

[Wherein X ″ represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom; Y ″ and Z ″ each independently represent at least one hydrogen atom as a fluorine atom; Represents an alkyl group having 1 to 10 carbon atoms and substituted with
X ″ is a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group has 2 to 6 carbon atoms, preferably 3 to 5 carbon atoms, Preferably it is C3.
Y ″ and Z ″ are each independently a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkyl group has 1 to 10 carbon atoms, preferably It is C1-C7, More preferably, it is C1-C3.
The carbon number of the alkylene group of X ″ or the carbon number of the alkyl group of Y ″ and Z ″ is preferably as small as possible because the solubility in the resist solvent is good within the above carbon number range.

  In addition, in the alkylene group of X ″ or the alkyl group of Y ″ and Z ″, as the number of hydrogen atoms substituted with fluorine atoms increases, the strength of the acid increases, and high-energy light or electron beam of 200 nm or less The ratio of fluorine atoms in the alkylene group or alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all. Are a perfluoroalkylene group or a perfluoroalkyl group in which a hydrogen atom is substituted with a fluorine atom.

  In this specification, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), and has a property of generating an acid upon irradiation with radiation. is there. Such oxime sulfonate-based acid generators are frequently used for chemically amplified resist compositions, and can be arbitrarily selected and used.

(In formula (B-1), R31 and R32 each independently represents an organic group.)
The organic group of R31 and R32 is a group containing a carbon atom and has an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (a fluorine atom, a chlorine atom, etc.)). It may be.

  The organic group for R31 is preferably a linear, branched or cyclic alkyl group or aryl group. These alkyl groups and aryl groups may have a substituent. There is no restriction | limiting in particular as this substituent, For example, a fluorine atom, a C1-C6 linear, branched or cyclic alkyl group etc. are mentioned. Here, “having a substituent” means that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent.

  As an alkyl group, C1-C20 is preferable, C1-C10 is more preferable, C1-C8 is more preferable, C1-C6 is especially preferable, and C1-C4 is the most preferable. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all of the hydrogen atoms are halogen atoms. Means an alkyl group substituted with Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.

The aryl group preferably has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. The partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated aryl group means that all of the hydrogen atoms are halogen atoms. Means an aryl group substituted with.
R31 is particularly preferably a C1-C4 alkyl group having no substituent or a C1-C4 fluorinated alkyl group.
The organic group for R32 is preferably a linear, branched or cyclic alkyl group, aryl group or cyano group. As the alkyl group and aryl group for R32, the same alkyl groups and aryl groups as those described above for R31 can be used.

  R32 is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

  More preferable examples of the oxime sulfonate-based acid generator include compounds represented by the following general formula (B-2) or (B-3).

[In Formula (B-2), R33 represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R34 is an aryl group. R35 is an alkyl group having no substituent or a halogenated alkyl group. ]

[In formula (B-3), R36 represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R37 is a divalent or trivalent aromatic hydrocarbon group. R38 is an alkyl group having no substituent or a halogenated alkyl group. p ″ is 2 or 3.]
In the general formula (B-2), the alkyl group or halogenated alkyl group having no substituent of R33 preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and more preferably 1 to 6 is most preferable.

  R33 is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.

  The fluorinated alkyl group for R33 preferably has 50% or more of the hydrogen atoms of the alkyl group, more preferably 70% or more, and even more preferably 90% or more.

  As an aryl group of R34, one hydrogen atom is removed from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthracyl group, or a phenanthryl group. Groups, and heteroaryl groups in which a part of the carbon atoms constituting the ring of these groups are substituted with a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Among these, a fluorenyl group is preferable.

  The aryl group of R34 may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, or an alkoxy group. The alkyl group or halogenated alkyl group in the substituent preferably has 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.

  The alkyl group or halogenated alkyl group having no substituent of R35 preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 6 carbon atoms.

  R35 is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group, and most preferably a partially fluorinated alkyl group.

  The fluorinated alkyl group in R35 preferably has 50% or more of the hydrogen atoms of the alkyl group, more preferably 70% or more, and even more preferably 90% or more fluorinated. Since the intensity | strength of increases, it is preferable. Most preferably, it is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted.

  In the general formula (B-3), examples of the alkyl group or halogenated alkyl group having no substituent for R36 include those similar to the alkyl group or halogenated alkyl group having no substituent for R33. It is done.

Examples of the divalent or trivalent aromatic hydrocarbon group for R37 include groups obtained by further removing one or two hydrogen atoms from the aryl group for R34.
Examples of the alkyl group or halogenated alkyl group having no substituent of R38 include the same alkyl groups or halogenated alkyl groups as those having no substituent of R35.
p ″ is preferably 2.

  Specific examples of the oxime sulfonate acid generator include α- (p-toluenesulfonyloxyimino) -benzyl cyanide, α- (p-chlorobenzenesulfonyloxyimino) -benzyl cyanide, α- (4-nitrobenzenesulfonyloxy). Imino) -benzylcyanide, α- (4-nitro-2-trifluoromethylbenzenesulfonyloxyimino) -benzylcyanide, α- (benzenesulfonyloxyimino) -4-chlorobenzylcyanide, α- (benzenesulfonyl) Oxyimino) -2,4-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -2,6-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -4-methoxybenzyl cyanide, α- ( 2-Chlorobenzenesulfonyloxyimino) 4-methoxybenzylcyanide, α- (benzenesulfonyloxyimino) -thien-2-ylacetonitrile, α- (4-dodecylbenzenesulfonyloxyimino) -benzylcyanide, α-[(p-toluenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α-[(dodecylbenzenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α- (tosyloxyimino) -4-thienyl cyanide, α- (methylsulfonyloxyimino) -1-cyclo Pentenyl acetonitrile, α- (methylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -1-cycloheptenylacetonitrile, α- (methylsulfonyloxyimino) -1-cyclooctene Acetonitrile, α- (trifluoromethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -cyclohexylacetonitrile, α- (ethylsulfonyloxyimino) -ethylacetonitrile, α- (propyl Sulfonyloxyimino) -propylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclopentylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclohexylacetonitrile, α- (cyclohexylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- ( Ethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclope N-tenyl acetonitrile, α- (n-butylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (ethylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclohexenylacetonitrile , Α- (n-butylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -phenylacetonitrile, α- (methylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (trifluoro Methylsulfonyloxyimino) -phenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -p- Butoxy phenylacetonitrile, alpha-(propylsulfonyl oxyimino)-p-methylphenyl acetonitrile, alpha-like (methylsulfonyloxyimino)-p-bromophenyl acetonitrile.

  Further, an oxime sulfonate-based acid generator disclosed in JP-A-9-208554 (paragraphs [0012] to [0014] [chemical formula 18] to [chemical formula 19]), WO2004 / 074242A2 (pages 65 to 85). The oxime sulfonate acid generators disclosed in Examples 1 to 40) of No. 1 can also be suitably used.

  Moreover, the following can be illustrated as a suitable thing.

  Of the above exemplified compounds, the following four compounds are preferred.

  Among diazomethane acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis (isopropylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, Bis (cyclohexylsulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane and the like can be mentioned.

  Further, diazomethane acid generators disclosed in JP-A-11-035551, JP-A-11-035552, and JP-A-11-035573 can also be suitably used.

  Examples of poly (bissulfonyl) diazomethanes include 1,3-bis (phenylsulfonyldiazomethylsulfonyl) propane and 1,4-bis (phenylsulfonyldiazo) disclosed in JP-A-11-322707. Methylsulfonyl) butane, 1,6-bis (phenylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (phenylsulfonyldiazomethylsulfonyl) decane, 1,2-bis (cyclohexylsulfonyldiazomethylsulfonyl) ethane, 1,3 -Bis (cyclohexylsulfonyldiazomethylsulfonyl) propane, 1,6-bis (cyclohexylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (cyclohexylsulfonyldiazomethylsulfonyl) decane, etc. Door can be.

(B) As a component, these acid generators may be used individually by 1 type, and may be used in combination of 2 or more type.
In the present invention, as the component (B), among the above, it is preferable to use an onium salt having a fluorinated alkyl sulfonate ion as an anion.
(B) Content of a component is 0.5-30 mass parts with respect to 100 mass parts of (A) component, Preferably it is 1-10 mass parts. By setting it within the above range, pattern formation is sufficiently performed. Moreover, since a uniform solution is obtained and storage stability becomes favorable, it is preferable.
<(C) component>
In the negative resist composition of the present invention, a crosslinking agent component (hereinafter referred to as “component (D)”) can be blended as an optional component.

  The component (C) is not particularly limited, and can be arbitrarily selected from cross-linking agents used in chemically amplified negative resist compositions known so far.

  Specifically, for example, 2,3-dihydroxy-5-hydroxymethylnorbornane, 2-hydroxy-5,6-bis (hydroxymethyl) norbornane, cyclohexanedimethanol, 3, 4, 8 (or 9) -trihydroxytri Aliphatic cyclic carbonization having a hydroxyl group or a hydroxyalkyl group or both such as cyclodecane, 2-methyl-2-adamantanol, 1,4-dioxane-2,3-diol, 1,3,5-trihydroxycyclohexane Examples thereof include hydrogen and oxygen-containing derivatives thereof.

  In addition, amino group-containing compounds such as melamine, acetoguanamine, benzoguanamine, urea, ethylene urea, propylene urea, glycoluril are reacted with formaldehyde or formaldehyde and a lower alcohol, and the hydrogen atom of the amino group is converted into a hydroxymethyl group or a lower alkoxymethyl. And a compound substituted with a group.

  Of these, those using melamine are melamine-based crosslinking agents, those using urea are urea-based crosslinking agents, those using alkylene ureas such as ethylene urea and propylene urea are alkylene urea-based crosslinking agents, and glycoluril is used. This was called a glycoluril-based crosslinking agent.

  The crosslinking agent component is preferably at least one selected from the group consisting of melamine-based crosslinking agents, urea-based crosslinking agents, alkylene urea-based crosslinking agents, and glycoluril-based crosslinking agents, and glycoluril-based crosslinking agents are particularly preferable. .

  Melamine-based crosslinking agents include compounds in which melamine and formaldehyde are reacted to replace the amino group hydrogen atom with a hydroxymethyl group, and melamine, formaldehyde and lower alcohol are reacted to convert the amino group hydrogen atom into a lower alkoxy group. Examples include compounds substituted with a methyl group. Specific examples include hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, hexabutoxybutyl melamine, and the like, among which hexamethoxymethyl melamine is preferable.

  Urea-based crosslinking agents include compounds in which urea and formaldehyde are reacted to replace amino group hydrogen atoms with hydroxymethyl groups, and urea, formaldehyde and lower alcohols are reacted to convert amino group hydrogen atoms into lower alkoxy groups. Examples include compounds substituted with a methyl group. Specific examples include bismethoxymethylurea, bisethoxymethylurea, bispropoxymethylurea, bisbutoxymethylurea, etc. Among them, bismethoxymethylurea is preferable.

  The compound represented by the general formula (C-1) can be obtained by a condensation reaction of alkylene urea and formalin and by reacting this product with a lower alcohol.

  Specific examples of the alkylene urea crosslinking agent include, for example, mono and / or dihydroxymethylated ethylene urea, mono and / or dimethoxymethylated ethylene urea, mono and / or diethoxymethylated ethylene urea, mono and / or dipropoxy Ethylene urea-based crosslinking agents such as methylated ethylene urea, mono and / or dibutoxymethylated ethylene urea; mono and / or dihydroxymethylated propylene urea, mono and / or dimethoxymethylated propylene urea, mono and / or diethoxymethyl Propylene urea-based crosslinkers such as propylene urea, mono and / or dipropoxymethylated propylene urea, mono and / or dibutoxymethylated propylene urea; 1,3-di (methoxymethyl) 4,5-dihydroxy-2- Imidazolidinone, 1,3-di (Metoki Like, etc.) -4,5-dimethoxy-2-imidazolidinone.

  Examples of the glycoluril-based crosslinking agent include glycoluril derivatives in which the N position is substituted with one or both of a hydroxyalkyl group and an alkoxyalkyl group having 1 to 4 carbon atoms. Such a glycoluril derivative can be obtained by a condensation reaction between glycoluril and formalin and by reacting this product with a lower alcohol.

Specific examples of the glycoluril-based crosslinking agent include, for example, mono, di, tri and / or tetrahydroxymethylated glycoluril, mono, di, tri and / or tetramethoxymethylated glycoluril, mono, di, tri and / or Examples include tetraethoxymethylated glycoluril, mono, di, tri and / or tetrapropoxymethylated glycoluril, mono, di, tri and / or tetrabutoxymethylated glycoluril.
As a crosslinking agent component, 1 type may be used independently and 2 or more types may be used in combination.

3-30 mass parts is preferable with respect to 100 mass parts of (A) component, as for content of a crosslinking agent component, 3-15 mass parts is more preferable, and 5-10 mass parts is the most preferable. When the content of the crosslinking agent component is at least the lower limit value, the crosslinking formation proceeds sufficiently and a good resist pattern can be obtained.
Moreover, when it is below this upper limit, the storage stability of the resist coating solution is good, and the deterioration of sensitivity with time is suppressed.
<(D) component>
The negative resist composition of the present invention may further contain a nitrogen-containing organic compound (D) (hereinafter referred to as “component (D)”) in order to improve the resist pattern shape, the stability over time, and the like. it can.

Since a wide variety of components (D) have already been proposed, any known one may be used. For example, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, monoalkylamines such as n-decylamine; dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, Tri-n-butylamine, tri-n-hexylamine, tri-n-pentylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decanylamine, tri-n- Trialkylamines such as dodecylamine; diethanolamine, trieta Ruamin, diisopropanolamine, triisopropanolamine, di -n- octanol amines, alkyl alcohol amines tri -n- octanol amine. Among these, a secondary aliphatic amine and a tertiary aliphatic amine are particularly preferable, a trialkylamine having 5 to 10 carbon atoms is more preferable, and tri-n-octylamine is most preferable.
These may be used alone or in combination of two or more.

(D) component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.
<(E) component>
In the negative resist composition of the present invention, an organic carboxylic acid or an organic carboxylic acid is further added as an optional component for the purpose of preventing sensitivity deterioration due to the blending of the component (D) and improving the resist pattern shape, retention stability and the like. Phosphorus oxoacid or derivative thereof (E) (hereinafter referred to as component (E)) can be contained. In addition, (D) component and (E) component can also be used together, and any 1 type can also be used.

  As the organic carboxylic acid, for example, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.

Phosphorus oxoacids or derivatives thereof include phosphoric acid, phosphoric acid di-n-butyl ester, phosphoric acid diphenyl ester and other phosphoric acid or derivatives thereof such as phosphonic acid, phosphonic acid dimethyl ester, phosphonic acid- Like phosphonic acids such as di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, phosphonic acid dibenzyl ester and derivatives thereof, phosphinic acids such as phosphinic acid, phenylphosphinic acid and their esters Among these, phosphonic acid is particularly preferable.
(E) A component is used in the ratio of 0.01-5.0 mass parts per 100 mass parts of (A) component.

The negative resist composition of the present invention may further contain miscible additives as desired, for example, additional resins for improving the performance of the resist film, surfactants for improving applicability, dissolution inhibitors, Plasticizers, stabilizers, colorants, antihalation agents, dyes, and the like can be added and contained as appropriate.
<(F) component>
The negative resist composition of the present invention can be produced by dissolving the components (A) and (B) and various optional components in an organic solvent (hereinafter sometimes referred to as component (F)). .

  As the component (F), any component can be used as long as it can dissolve each component to be used to form a uniform solution, and any one of conventionally known solvents for chemically amplified resists can be used. Two or more types can be appropriately selected and used.

For example, lactones such as γ-butyrolactone, ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-amyl ketone, methyl isoamyl ketone, 2-heptanone; multivalents such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol Alcohols: compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl ether of the polyhydric alcohols or compound having the ester bond , Ether bond such as monoalkyl ether such as monopropyl ether, monobutyl ether or monophenyl ether Polyhydric alcohols derivatives, such as compounds having [Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) are preferable];
Cyclic ethers such as dioxane and esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; Aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, amylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene, etc. be able to.

  These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.

  Moreover, the mixed solvent which mixed PGMEA and the polar solvent is preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.

  More specifically, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, Most preferably, it is 5: 5 8: 2.

The amount of the component (F) used is not particularly limited, but is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. -20% by mass, preferably 2-15% by mass.
≪Pattern formation method≫
The pattern forming method of the present invention includes a step of forming a resist film on a substrate using the negative resist composition of the present invention, a step of exposing the resist film, and developing the resist film to form a resist pattern. Including a process.

  More specifically, for example, a resist pattern can be formed by the following resist pattern forming method. That is, first, the negative resist composition is applied onto a substrate such as a silicon wafer with a spinner or the like, and optionally pre-baked (PAB) to form a resist film. The formed resist film is selectively exposed by, for example, exposure through a mask pattern or drawing by direct irradiation of an electron beam without using a mask pattern, using an exposure apparatus such as an electron beam lithography apparatus or an EUV exposure apparatus. After that, PEB (post-exposure heating) is performed.

Subsequently, after developing with an alkali developer, rinsing is performed, and the developer on the substrate and the resist composition dissolved by the developer are washed away and dried to obtain a resist pattern.
These steps can be performed using a known method. The operating conditions and the like are preferably set as appropriate according to the composition and characteristics of the negative resist composition to be used.

  The exposure light source is not particularly limited and is performed using radiation such as ArF excimer laser, KrF excimer laser, F2 excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), electron beam, X-ray, soft X-ray. Can do. In particular, the negative resist composition according to the present invention is effective for electron beams or EUV, particularly electron beams.

  In some cases, the post-baking step after alkali development may be included, and an organic or inorganic antireflection film may be provided between the substrate and the resist film.

  As described above, according to the resist pattern forming method using the negative resist composition of the present invention, a resist pattern with reduced roughness and excellent resolution can be formed.

Examples of the present invention will be described below, but the scope of the present invention is not limited to these examples.
<Example 1>

  This example relates to the synthesis of an additive compound (hereinafter also referred to as (Group I)) used in the negative resist composition of the present invention. Table 1 shows polynuclear phenols, halogen compounds, and produced additive components used as raw materials. In Table 1, each compound name is indicated by an abbreviation, but the structure of each compound is represented by the following chemical formula.

  Polynuclear phenol 25X-MBSA (15 g) and potassium carbonate (7 g) were added to acetone (300 ml) and stirred well. A solution of α-bromo-γ-butyrolactone (6.0 g) in acetone (50 ml) was added thereto at room temperature, and the mixed solution was stirred for 2 hours. After the reaction, water (50 ml) was added and acetone was distilled off under reduced pressure. THF (300 ml) was added and 2.38% TMAH aqueous solution was added with stirring until the pH was about 11. After stirring at room temperature for 2 hours, THF was distilled off under reduced pressure, ethyl acetate (200 ml) was added, and 1% aqueous hydrochloric acid was added until the pH reached about 5 with vigorous stirring. The organic layer was washed with water and saturated brine, dried over sodium sulfate, and concentrated to obtain an additive compound (25X-MBSA-1) (16 g). The average number of γ-hydroxycarboxylic acids introduced from 1H-NMR was 2.0 per molecule. As a result of high-performance liquid chromatography analysis, 25X-MBSA-1 was found to be free from α-bromo-γ-butyrolactone as a synthetic raw material and its decomposition by-product. As a result of FT-IR spectrum measurement, an absorption peak derived from the carbonyl group of the lactone ring was confirmed at 1780 cm-1, and a group containing a lactone ring was introduced into polynuclear phenol 25X-MBSA via an ether bond. Became clear.

  By the same synthesis method, additive compounds were synthesized using the compounds shown in Table 1. All compounds were subjected to structure and composition determination by high performance liquid chromatography, FT-IR and 1H-NMR measurement.

In Table 1, the composition represents the average number of functional groups containing a lactone ring, methyl group, phenacyl group, or benzyl group introduced per molecule.

  Table 1 also shows the dissolution rate of the produced compound in an alkaline developer (2.38% tetramethylammonium hydroxide aqueous solution) of the amorphous film obtained from the cyclohexanone solution.

The structural formula shown here is a case where the introduced functional group is butyrolactone (BL).
<Example 2>

  This example relates to the synthesis of additive components (Group I) used in the negative resist composition of the present invention. 3M6C-MBSA-BL3 was synthesized by performing a two-step reaction.

Bis (3-formyl-4-hydroxyphenyl) methane (compound (1)) (5.13 g, 20 mmol) and α-bromo-γ-butyrolactone (13.2 g, 40 mmol) were dissolved in acetone (100 ml) to obtain potassium carbonate. (11.1 g, 40 mmol) was added and allowed to react for 4 hours under reflux conditions. After completion of the reaction, the precipitated solid content was filtered off, and the solution was concentrated (water and ethyl acetate were added in the middle, and acetone was removed). Further, this was washed with water (three times), the organic layer was concentrated, and purified with a silica gel column (SiO ₂ 150 g, hexane-ethyl acetate) to obtain 8 g of the desired lactone compound (compound (2)).

This compound (2) was analyzed by 1H-NMR and IR. The results are shown below.
1H-NMR data (solvent: DMSO-d6, internal standard: TMS):
δ (ppm) = 10.33 s 2H Ha, 7.55-7.66 m 4H Hb, c, 7.32 s 2H Hd, 5.49 t 2H He, 4.25-4.54 m 4H Hf, 3.38 s 2H Hg, 2.32-2.88 m 4H Hh.
IR data: 2920 cm-1, 1782 cm-1, 1680 cm-1, 1245 cm-1.

The above compound (2) (4 g, 9.4 mmol) was dissolved in methanol-THF (100 ml, 1: 1), 2-cyclohexyl-5-methylphenol (14.3 g, 75.3 mmol) and concentrated hydrochloric acid (8 g) were added, The reaction was performed at 60 ° C. for 10 hours. After completion of the reaction, the mixture was neutralized with sodium hydroxide, methanol and THF were concentrated and removed under reduced pressure, and the product was extracted with ethyl acetate (100 ml) and washed with water (3 times). The residue obtained by concentrating the organic layer was purified by a silica gel column (SiO ₂ 100 g, hexane-ethyl acetate) to obtain 6 g of the target product, γ-butyrolactone derivative 3M6C-MBSA-BL3 (compound (3)). It was.

This compound (3) was analyzed by 1H-NMR and IR. The results are shown below.
1H-NMR data (solvent: DMSO-d6, internal standard: TMS): δ (ppm) = 7.80-7.91 m 4H Ha, 6.55-7.14 m 14H Hb, 5.83-5 .90 m 2H Hc, 4.83-4.94 m 2H Hd, 3.92-4.22 m 4H He, 3.63 s 2H Hf, 0.99-2.19 m 60H Hh, g, i.
IR data: 3450 cm-1, 2920 cm-1, 2860 cm-1, 1781 cm-1.

  The names (abbreviations) and chemical formulas of additive components obtained by the same synthesis method are shown below.

<Example 3>

  This example relates to the synthesis of a compound having a functional group that is chemically converted by the action of an acid and has reduced solubility in an alkaline developer, which is used in the negative resist composition of the present invention.

  The γ-butyrolactone derivative 3M6C-MBSA-BL3 (compound (3)) (6 g) was dissolved in THF (100 ml), and 2% aqueous sodium hydroxide solution (100 ml) was added. The alkali hydrolysis reaction was performed at room temperature for 60 minutes. After the reaction, the reaction solution was concentrated, neutralized with hydrochloric acid, ethyl acetate (100 ml) and distilled water (100 ml) were added, and the organic layer was washed three times with distilled water (100 ml). The organic layer was concentrated and vacuum-dried to obtain 5.8 g of the target γ-hydroxycarboxylic acid derivative (compound (4)).

  The butyrolactone and valerolactone product of the (nuclear group I) polynuclear phenol compound obtained in Examples 1 and 2 were subjected to the same hydrolysis reaction, and the compounds shown in Table 2 (hereinafter referred to as (Group S)). Got.

<Example 4>

  In this example, from a solution in which a compound (S group) having a functional group which is chemically converted by the action of an acid and has reduced solubility in an alkaline developer is used in the negative resist composition of the present invention in a resist solvent. The result of having measured the dissolution rate with respect to the alkaline developing solution of the obtained coating film is shown.

  A solution of compound 25X-MBSA-BL1-S (300 mg) and acid generator triphenylsulfonium triflate (TPS-TF) (30 mg) in propylene glycol monomethyl ether acetate (PGMEA) (10 g) After spin-coating on top, it was heated at 100 ° C. for 2 minutes to obtain an amorphous coating film having a thickness of 200 nm. The dissolution rate of this coating film in an alkaline developer (tetrahydroammonium hydroxide aqueous solution) was measured. The concentration of the alkali developer was measured at 3.38%, 1.19%, and 0.79%.

  Similarly for the hydrolysis products shown in Table 2 other than 25X-MBSA-BL1-S, an amorphous film was prepared from a mixed solution with the acid generator TPS-TF, and the dissolution rate was measured. The results are shown in Table 3.

In Table 3, the dissolution rate “> 100” represents that the amorphous film was instantaneously dissolved.
<Example 5>

This example relates to the negative resist composition of the present invention. Each component shown in Table 4 was mixed and dissolved to obtain a negative resist composition (solution). As the solvent, 2-methoxy-1-propanol (propylene glycol monomethyl ether, PGME) was used.
A resist thin film having a film thickness of 100 to 120 nm was formed on a silicon wafer by spin coating, and prebaked at 100 ° C. for 2 minutes. Thereafter, a fine line & space pattern was drawn with an electron beam (EB) at an acceleration voltage of 70 kV, and post-exposure baking was performed at 100 ° C. for 2 minutes. Development was performed with a 2.38% TMAH (tetramethylammonium hydroxide) aqueous solution or a TMAH aqueous solution having a concentration such that the dissolution rate of the unexposed portion of the resist thin film was 2 to 50 nm / s.

Table 4 shows the composition of the resist composition and the EB lithography evaluation results. Hitachi HL-800D was used for EB drawing. LER was calculated from a 100 nm line & space pattern using a length measurement SEM.
In Table 4, the value in parentheses represents the composition ratio (% by weight) in the resist composition (solution). Each resist contains 0.005% of the basic compound trioctylamine.

  FIG. 1 is a sensitivity curve of 1 resist. FIG. It is a SEM photograph which shows the result of the resolution evaluation of a 60 nm line & space pattern obtained by 1 resist.

Table per 4 nine resist performs the same evaluation, except that perform EUV exposure instead of EB drawing, any resist the sensitivity 10 mJ / cm ² from 30 mJ / cm ² at 40nm or less lines and spaces solutions I imaged it.
<Comparative example 1>

This comparative example relates to a negative resist composition containing no additive component.
A negative resist composition solution was prepared by mixing and dissolving each component with the composition shown in Table 5. A resist thin film having a film thickness of 100 to 120 nm was formed on a silicon wafer by spin coating, and prebaked at 100 ° C. for 2 minutes. Thereafter, a fine line & space pattern was drawn with an electron beam (EB) at an acceleration voltage of 70 kV, and post-exposure baking was performed at 100 ° C. for 2 minutes. Development was performed with an appropriate developer.
Table 5 shows the composition of the resist composition and the EB lithography evaluation results. Hitachi HL-800D was used for EB drawing. LER was calculated from a 100 nm line & space pattern using a length measurement SEM.
In Table 5, the value in parentheses represents the composition ratio (% by weight) in the resist composition (solution). Each resist contains 0.005% of the basic compound trioctylamine.

<Example 6>

Selected from the six polynuclear phenols (25X-MBSA, 26X-MBSA, 3M6C-MBSA, 25X-D, 26X-D, 3M6C-D) shown in Chemical Formula 35 and the compounds of (Group I) in Table 2 A resist composition of PGMEA solution containing 1% by weight of at least one compound and 2% by weight of at least one compound selected from the compounds of (S group) in Table 2 was prepared. In this resist composition, the type and combination of compounds are selected so that the dissolution rate of the resist film after coating and pre-baking in 2.38% TMAH (tetramethylammonium hydroxide aqueous solution) is 2 to 50 nm / s. It is. Using this resist, a resist thin film having a film thickness of 100 to 120 nm was formed on a silicon wafer by spin coating, and prebaked at 100 ° C. for 2 minutes. Thereafter, a fine line & space pattern was drawn with an electron beam (EB) at an acceleration voltage of 70 kV, and post-exposure baking was performed at 100 ° C. for 2 minutes. Development was performed with an appropriate developer.
When the developed pattern was observed with a cross-sectional SEM, a line and space pattern of 50 to 60 nm was formed at an irradiation dose of 10 to 50 μC / cm ² .
<Example 7>

In this embodiment, a method for manufacturing a transistor using the pattern formation method of the present invention will be described.
FIG. 3 shows a cross-sectional view of a known MOS (metal-oxide-semiconductor) transistor. The transistor has a structure in which a drain current flowing between the source electrode 36 and the drain electrode 37 is controlled by a voltage applied to the gate electrode 38. Here, the process of making such a structure is composed of more than a dozen processes. However, if these are roughly divided, they can be divided into three groups: a process up to field oxide film formation, a process up to gate formation, and a final process. it can. Here, the first process up to the formation of the field oxide film (FIG. 4) includes a process of forming a resist pattern on the silicon nitride film. The field oxide film was formed as in the following examples.

  As shown in FIG. 4A, a 20 nm oxide film 42 is formed on a p-type silicon wafer 41 by a known method, and a 70 nm silicon nitride film is formed thereon by plasma CVD to form a substrate. To this substrate, the materials shown in Example 1, No. 5 in Example 5, were used. A resist pattern 44 of 50 nm line is formed by the pattern forming method using the resist composition 1 (FIG. 4B). After etching the silicon nitride film by a known method using this resist pattern as a mask (FIG. 4C), boron ion implantation for a channel stopper is performed using this resist as a mask again.

  After removing the resist (FIG. 4D), a field oxide film of 0.5 μm is formed in the element isolation region by selective oxidation using the silicon nitride film as a mask (FIG. 4E). Thereafter, a gate forming step and a final step were performed according to a known method. After etching the silicon nitride film, the gate is oxidized to grow polycrystalline silicon (FIG. 4F). A 50 nm line resist pattern is formed on this substrate using the pattern forming method shown in Example 1 (FIG. 4G). Using this resist pattern as a mask, the polycrystalline silicon is etched by a known method to form a gate (FIG. 4H). A thin oxide film of the source and drain is etched, and then arsenic is diffused into the polycrystalline silicon gate, the source and the drain, and an oxide film is formed in the polycrystalline silicon gate and the source and drain regions. Contacts for aluminum wiring to the gate, source, and drain are opened, aluminum deposition and patterning are performed, a protective film is further formed, and pads for bonding are opened. In this way, a MOS transistor as shown in FIG. 3 is formed.

Although a method for forming a field oxide film has been particularly described here for a MOS transistor, the present invention is not limited to this and can be applied to other methods and processes for manufacturing semiconductor devices.
<Example 8>

In this example, No. 5 in Example 5 was used. A method for manufacturing a semiconductor memory element using the resist composition 2 will be described with reference to FIGS. FIG. 5 is a cross-sectional view showing the main steps of manufacturing the device. As shown in FIG. 5A, a P-type Si semiconductor 50 is used as a substrate, and an element isolation region 51 is formed on the surface using a known element isolation technique. Next, for example, a word line 52 having a structure in which polycrystalline Si having a thickness of 150 nm and SiO ₂ having a thickness of 200 nm is stacked is formed, and further, for example, SiO ₂ having a thickness of 150 nm is deposited by chemical vapor deposition. The SiO ₂ side spacers 53 are formed on the side walls of the word lines by processing in a lateral direction. Next, the n diffusion layer 54 is formed by a normal method. Next, as shown in FIG. 5B, a data line 55 made of polycrystalline Si, refractory metal silicide, or a laminated film thereof is formed through a normal process. Next, as shown in FIG. 5C, a storage electrode 56 made of polycrystalline Si is formed through a normal process. Thereafter, Ta ₂ O ₅ , Si ₃ N ₄ , SiO ₂ , BST, PZT, a ferroelectric, or a composite film thereof is deposited to form a capacitor insulating film 57. Subsequently, a polycrystalline silicon, a refractory metal, a refractory metal silicide, or a low-resistance conductor such as Al or Cu is deposited to form a plate electrode 58. Next, as shown in FIG. 5D, a wiring 59 is formed through a normal process. Next, a memory element was manufactured through a normal wiring formation process and a passivation process. In addition, although only the typical manufacturing process was demonstrated here, the normal manufacturing process was used except this.

  In this example, the pattern formation of the various element structures was performed using the resist according to the present invention and EUV / EB exposure. Note that the resist material according to the present invention was not applied to a process having a relatively large pattern size, such as a conductive hole forming process in a passivation process and a pattern forming process in an ion implantation mask forming process.

  Next, a pattern formed by lithography will be described. FIG. 6 shows a pattern arrangement of a memory portion of a typical pattern constituting the manufactured memory element. 60 is a word line, 61 is a data line, 62 is an active region, 63 is a storage electrode, and 64 is a pattern of electrode extraction holes. Also in this example, the pattern formation of the embodiment of the present invention was used for all except the 64 electrode extraction hole formation shown here. The present invention is used in a process using the minimum design rule other than the pattern formation shown here.

  The device manufactured using the present invention can reduce the dimension between patterns as compared with the device manufactured using the conventional method. For this reason, elements having the same structure can be made smaller, and the number of wafers that can be manufactured from a single wafer when manufacturing semiconductor elements has increased, thereby improving the yield.

It is a figure which shows the sensitivity curve by electron beam exposure of the negative resist composition of this invention. It is a SEM photograph which shows the result of the resolution evaluation of the negative resist composition of this invention. It is sectional drawing of a MOS (metal-oxide-semiconductor) type | mold transistor. (A)-(h) is sectional drawing which shows typically the preparation process of the device using the pattern formation method of this invention. (A)-(d) is sectional drawing which shows typically the preparation process of the device using the pattern formation method of this invention. It is a schematic diagram which shows the planar structure of the device using the pattern formation method of this invention.

Explanation of symbols

  32, 45 ... Field oxide film, 33 ... Source contact, 34 ... Drain contact, 35 ... Polycrystalline silicon, 36 ... Source electrode, 37 ... Drain electrode, 38 ... Gate electrode, 39 ... Protective film, 42 ... Oxide film, 44 ... Resist pattern, 46 ... polycrystalline silicon film, 47 ... resist pattern, 48 ... polycrystalline silicon gate, 50 ... P-type Si semiconductor, 51 ... element isolation region, 52 ... word line, 53 ... side spacer, 54 ... n Diffusion layer, 55 ... data line, 56 ... storage electrode, 57 ... capacitor insulating film, 58 ... plate electrode, 59 ... wiring, 60 ... word line, 61 ... data line, 62 ... active region, 63 ... storage electrode, 64 ... electrode extraction hole.

Claims (19)

Consists of a compound having a functional group represented by the following general formula (S-1), having a functional group that is chemically converted by the action of an acid and whose solubility in an alkaline developer decreases, and an additive compound represented by the general formula (I-1) A base component (A) to be produced;
A negative resist composition comprising an acid generator component (B) that generates an acid upon irradiation with radiation.

[In Formula (S-1), Z ¹ , Z ² , Z ³ , Z ⁴ , Z ⁵ and Z ⁶ each independently have a hydrogen atom or a hydroxycarboxylic acid which is opened by hydrolyzing a lactone ring. Wherein R ^{11 to} R ¹⁷ are each independently an alkyl group, an alkenyl group or an aromatic hydrocarbon group having 1 to 10 carbon atoms, and the structure thereof May contain a heteroatom; ga, gb, gc, gd, j are each independently an integer of 1 or more, k, q are 0 or an integer of 1 or more, and ga + j + k + q, gb + j + k + q, gc + j + k + q, and gd + j + k + q is 5 or less; h is an integer of 1 or more, l and m are each independently 0 or an integer of 1 or more, and h + l + m is 4 or less; i is 1 or less N and o are each independently an integer of 0 or 1 and i + n + o is 4 or less; X is an aliphatic cyclic group or an aromatic cyclic group. ]

[In Formula (I-1), Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ are each independently a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group or an aromatic hydrocarbon group, a group having the lactone ring, alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group are present 0 to 4 per molecule,; ^{R. 21 to} R ²⁷ is each independently an alkyl group, alkenyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms and may contain a hetero atom in the structure thereof; ge, gf, gg, gh and j2 are each independently And k2 and q2 are 0 or an integer of 1 or more and (ge + j2 + k2 + q2), (gf + j2 + k2 + q2), (gg + j2 + k2 + q2), and (gh + j2 +) k2 + q2) is 5 or less; h2 is an integer of 1 or more, l2, m2 are each independently 0 or an integer of 1 or more, and h2 + l2 + m2 is 4 or less; i2 is an integer of 1 or more; n2, o2 are each independently 0 or an integer of 1 or more, and i2 + n2 + o2 is 4 or less; X is an alkylene group, cycloaliphatic aliphatic cyclic group or an aromatic cyclic group. ]   The negative resist composition of Claim 1 containing a nitrogen-containing organic compound (D). 2. The negative according to claim 1, wherein the compound having a functional group that is chemically converted by the action of an acid and has reduced solubility in an alkali developer is a compound represented by the general formula (S-2). Type resist composition.

[In Formula (S-2), Z ¹ , Z ² , Z ³ , Z ⁴ , Z ⁵ and Z ⁶ each independently have a hydrogen atom or a hydroxycarboxylic acid which is opened by hydrolyzing a lactone ring. And at least one hydroxycarboxylic acid is present per molecule; R ³¹ and R ³² are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, X may be an aliphatic cyclic group or an aromatic cyclic group. ]   The negative resist composition of Claim 3 containing a nitrogen-containing organic compound (D). 2. The negative according to claim 1, wherein the compound having a functional group that is chemically converted by the action of an acid and has reduced solubility in an alkaline developer is a compound represented by the general formula (S-3). Type resist composition.

[In the formula (S-3), Z is a group having a hydroxycarboxylic acid that is opened by hydrolysis of a lactone ring; R ^{51 to} R ⁵⁷ are each independently an alkyl group having 1 to 10 carbon atoms, alkenyl A group or an aromatic hydrocarbon group which may contain a hetero atom in the structure; ga, gb, gc, gd and j are each independently an integer of 1 or more, and k and q are 0 or 1 (Ga + j + k + q), (gb + j + k + q), (gc + j + k + q), and (gd + j + k + q) are 5 or less; h is an integer of 1 or more, and l and m are each independently 0 or 1 or more is an integer, and h + l + m is 4 or less; i represents an integer of 1 or greater, n, o are each independently 0 or an integer of 1 or more, and i + n + o is 4 or less; X is An aliphatic cyclic group or an aromatic cyclic group. ]   The negative resist composition of Claim 5 containing a nitrogen-containing organic compound (D). 2. The negative according to claim 1, wherein the compound having a functional group which is chemically converted by the action of an acid and has reduced solubility in an alkaline developer is a compound represented by the general formula (S-4). Type resist composition.

[In Formula (S-4), Z is a group having a hydroxycarboxylic acid that is opened by hydrolysis of a lactone ring; R ⁷¹ and R ⁷² are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic group; A hydrocarbon group which may contain heteroatoms in its structure; X is an aliphatic cyclic group or an aromatic cyclic group. ]   The negative resist composition of Claim 7 containing a nitrogen-containing organic compound (D). The negative resist composition according to claim 1, wherein the additive compound is a compound represented by the general formula (I-2).

[In formula (I-2), Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ are each independently a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, or an alkenyl group. Or an aromatic hydrocarbon group, the group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group or an aromatic hydrocarbon group is present in an amount of 0 to 4 per molecule; R ⁴¹ , R ⁴² Each independently represents an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure; X represents an alkylene group, an aliphatic cyclic group or an aromatic cyclic group; is there. ]   The negative resist composition of Claim 9 containing a nitrogen-containing organic compound (D). The negative resist composition according to claim 1, wherein the additive compound is a compound represented by the general formula (I-3).

[In Formula (I-3), Y represents a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, or an aromatic hydrocarbon group; R ^{61 to} R ⁶⁷ are each independently An alkyl group, an alkenyl group or an aromatic hydrocarbon group having 1 to 10 carbon atoms, which may contain a hetero atom in the structure thereof; ge, gf, gg, gh and j2 are each independently an integer of 1 or more K2, q2 is 0 or an integer of 1 or more, and (ge + j2 + k2 + q2), (gf + j2 + k2 + q2), (gg + j2 + k2 + q2), and (gh + j2 + k2 + q2) are 5 or less; h2 is an integer of 1 or more, l2, m2 Are each independently an integer of 0 or 1 and h2 + l2 + m2 is 4 or less; i2 is an integer of 1 or more, and n2 and o2 are Independently 0 or an integer of 1 or more is, and i2 + n2 + o2 is 4 or less; X is an alkylene group, an aliphatic cyclic group or an aromatic cyclic group. ]   The negative resist composition of Claim 11 containing a nitrogen-containing organic compound (D). The negative resist composition according to claim 1, wherein the additive compound is a compound represented by the general formula (I-4).

[In Formula (I-4), Y is a hydrogen atom, a group having a lactone ring, an alkyl group having 1 to 20 carbon atoms, an alkenyl group or an aromatic hydrocarbon group; R ⁸¹ and R ⁸² are each independently An alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group which may contain a hetero atom in the structure; X is an alkylene group, an aliphatic cyclic group or an aromatic cyclic group; ]   The negative resist composition of Claim 13 containing a nitrogen-containing organic compound (D).   The base component (A) according to claim 1, wherein the content of the compound having a functional group that is chemically converted by the action of an acid and decreases in solubility in an alkali developer is 40% by weight or more. Negative resist composition.   The negative resist composition according to claim 15, comprising a nitrogen-containing organic compound (D).   Negative type containing at least one compound having a functional group that is chemically converted by the action of the acid and has reduced solubility in an alkaline developer, and at least one additive compound represented by (I-1). 2. The negative resist composition according to claim 1, wherein the resist film obtained from the resist composition has a dissolution rate in a developing solution of 2 nm / s or more and 50 nm / s or less. object.   The negative resist composition according to claim 1, wherein the hydroxycarboxylic acid is γ-hydroxycarboxylic acid or δ-hydroxycarboxylic acid. Forming a resist film on a substrate using the negative resist composition according to claim 1;
Exposing the resist film;
Developing the resist film to form a resist pattern.

Images