WO2008026422A1 - Compound, positive-type resist composition, and method for formation of resist pattern - Google Patents

Abstract

Disclosed are: a compound which can be used in a resist composition; a positive-type resist composition comprising the compound; and a method for the formation of a resist pattern. Specifically disclosed is a compound represented by the general formula (A-1) [wherein R' represents a hydrogen atom or an acid-labile-dissolution-inhibiting group, provided that at least one or some of multiple R's are acid-labile-dissolution-inhibiting groups; R'' represents an alkyl group having 1 to 10 carbon atoms; R11 to R17 independently represents an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group which may contain a heteroatom in its structure; g and j independently represent an integer of 1 or greater; k and q independently represent an integer of 0 or greater; a represents an integer ranging from 1 to 3; b represents an integer of 1 or greater; l and m independently represent an integer of 0 or greater; c represents an integer of 1 or greater; n and o independently represent an integer of 0 or greater; and A represents a group represented by the general formula (Ia), a group represented by the general formula (Ib) or an aliphatic cyclic group].

Description

 Specification

 Compound, positive resist composition, and method for forming resist pattern

 The present invention relates to a compound that can be used as a resist composition, a positive resist composition containing the compound, and a resist pattern forming method using the positive resist composition.

 This application (May 2006, August 30, 2006, Japanese Patent Application No. 2006-234558 filed) This application claims priority and is incorporated herein by reference.

 Background art

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

 As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, the power used in the past, typically ultraviolet rays such as g-line and i-line, is now in the process of mass production of semiconductor devices using KrF excimer laser and ArF excimer laser. Also, these excimer lasers have shorter wavelength than F excimer laser, electron beam, EU

 2

 V (extreme ultraviolet rays) and X-rays!

 Also, as one of the pattern forming materials that can form a pattern with fine dimensions, a chemically amplified resist containing a base material component capable of forming a film and an acid generator component that generates an acid upon exposure is known. It has been. Chemically amplified resists are classified into a negative type in which alkali solubility is reduced by exposure and a positive type in which alkali solubility is increased by exposure.

[0003] Conventionally, polymers have been used as the base component of such chemically amplified resists, such as polyhydroxystyrene (PHS) and resins in which a part of the hydroxyl groups are protected with acid dissociable, dissolution inhibiting groups, etc. PHS resins, copolymers derived from (meth) acrylic acid esters, and resins in which a part of the carboxy group is protected with an acid dissociable, dissolution inhibiting group 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 and the surface of the side wall. For example, resist pattern The roughness of the sidewall surface, that is, the line edge roughness (LER), causes distortion around the hole in the hole pattern and variations in the line width in the line and space pattern, which adversely affects the formation of fine semiconductor elements. There is a risk of giving. Such a problem becomes more serious as the pattern size is smaller. For this reason, for example, in lithography using an electron beam or EUV, the ability to form a fine pattern of several tens of nanometers and the extremely low roughness exceeding the current pattern roughness are required.

 However, polymers generally used as base materials have a large molecular size (average square radius per molecule) of around several nm. In the patterning development process, the dissolution behavior of the resist in the developing solution is usually carried out 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.

[0004] To solve such problems, a resist using a low molecular weight 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 a low molecular weight material having an alkali-soluble group such as a hydroxyl group or a carboxy group, part or all of which is protected with an acid dissociable, dissolution inhibiting group. .

 Non-Patent Document 1: T. Hirayama, D. Shiono, H. Hada and J. Onodera: J. Phot opolym. Sci. Technol. 17 (2004), p435

 Non-Patent Document 2: Jim—Baek Kim, Hyo—Jin Yun, Young—Gil Kwon: Chemis try Letters (2002), pl064 ~ 1065

 Disclosure of the invention

 Problems to be solved by the invention

[0005] Such a low molecular weight material is expected to be able to reduce roughness due to a small molecular size because of its low molecular weight. Therefore, there is an increasing demand for new low molecular weight materials that can be used for resist compositions!

 The present invention has been made in view of the above circumstances, and uses a compound that can be used as a resist composition, a positive resist composition containing the compound, and the positive resist composition. An object of the present invention is to provide a resist pattern forming method.

 Means for solving the problem

[0006] A first aspect of the present invention that solves the above problems is represented by the following general formula (A-1). It is a compound.

[Chemical 1]

[In the formula (A-1), R ′ is a hydrogen atom or an acid dissociable, dissolution inhibiting group, and a plurality of R ′ may be the same or different from each other. At least some of them are acid-dissolvable dissolution inhibiting groups; R ″ is an alkyl group having 1 to 10 carbon atoms; R ^{U to} R ¹⁷ are each independently an alkyl group having 1 to 10 carbon atoms; A group or an aromatic hydrocarbon group which may contain a hetero atom in the structure; g and j are each independently an integer of 1 or more, k and q are integers of 0 or more, and g + j + k + q is 5 or less; a is an integer of 1 to 3; b is an integer of 1 or more, 1 and m are each independently an integer of 0 or more, and b + 1 + m Is an integer greater than or equal to 1, n and o are each independently an integer greater than or equal to 0, and c + n + o is less than or equal to 4; A is the following general formula (la) Represented by the following general formula (lb) Or an aliphatic cyclic group.]

[Chemical 2]

 I a) (I b)

[In the formula (la), R ¹⁸ and R ¹⁹ are each independently an alkyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms, and may contain a hetero atom in the structure thereof; r, y , Z are each independently an integer of 0 or more, and r + y + z is 4 or less. ]

 The second aspect (aspect) of the present invention is a substrate type containing a base component (A) whose alkali solubility is increased by the action of an acid and an acid generator component (B) which generates an acid upon irradiation with radiation. A resist composition comprising:

 The substrate component (A) contains a compound (A1) represented by the following general formula (A-1).

[Chemical 3]

[In the formula (A-1), R ′ is a hydrogen atom or an acid dissociable, dissolution inhibiting group, and a plurality of R ′ may be the same or different from each other. At least some of them are acid-dissolving dissolution inhibiting groups; R ″ is an alkyl group having 1 to 10 carbon atoms; and R ^{U to} R ¹⁷ are respectively Each independently an alkyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms, which may contain a heteroatom in the structure; g and j are each independently an integer of 1 or more, k, q Is an integer greater than or equal to 0 and g + j + k + q is less than or equal to 5; a is an integer from 1 to 3; b is an integer greater than or equal to 1, and m is independently greater than or equal to 0 And b + 1 + m is 4 or less; c is an integer of 1 or more, n and o are each independently an integer of 0 or more, and c + n + o is 4 or less Yes; A is a group represented by the following general formula (la), a group represented by the following general formula (lb), or an aliphatic cyclic group. ]

[In the formula (la), R ¹⁸ and R ¹⁹ are each independently an alkyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms, and may contain a hetero atom in the structure thereof; r, y , Z are each independently an integer of 0 or more, and r + y + z is 4 or less. ]

[0008] Further, a third aspect (aspect) of the present invention is a pattern forming method, wherein a resist film is formed on a substrate using the positive resist composition of the second aspect (aspect). A step, exposing the resist film, and developing the resist film to form a resist pattern.

 [0009] Here, the "alkyl group" in the claims and the specification includes linear, branched and cyclic monovalent saturated hydrocarbon groups unless otherwise specified.

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

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

 The invention's effect

[0010] According to the present invention, a compound that can be used as a resist composition, containing the compound A positive resist composition and a resist pattern forming method using the positive resist composition are provided.

 Brief Description of Drawings

 FIG. 1 is a view showing a sensitivity curve of a resist composition of one example of the present invention by electron beam exposure.

 BEST MODE FOR CARRYING OUT THE INVENTION

 [0012] << Compound >>

 The compound of the present invention (hereinafter referred to as compound (A1) and) is represented by the above general formula (A-1). In the general formula (A-1), the acid dissociable, dissolution inhibiting group for R ′ has an alkali dissolution inhibiting property that makes the compound (A1) insoluble before dissociation, and after dissociation, the compound (A1) It is a group that changes to alkali-soluble. Therefore, in the compound (A1), when it is mixed with the acid generator component (B) in the positive resist composition as described later, when the acid generated from the acid generator component (B) by exposure acts, The acid dissociable, dissolution inhibiting group dissociates, and the compound (A1) changes from alkali-insoluble to alkali-soluble.

[0013] The acid dissociable, dissolution inhibiting group is not particularly limited, and has been proposed for hydroxystyrene-based resins, (meth) acrylic acid-based resins, and the like used in chemically amplified resist compositions for KrF and ArF. It can be used by appropriately selecting from unreasonable forces. Specific examples include a tertiary alkyl group, a tertiary alkyloxycarbonyl group, an alkoxycarbonylalkyl group, an alkoxyalkyl group, and a cyclic ether group.

Specific examples of the tertiary alkyl group include chain-like tertiary alkyl groups such as tert-butyl group and tert-amyl group, 2-methyl-2-adamantyl group, and 2-ethyl-2-adamantyl group. And tertiary alkyl groups containing an aliphatic cyclic group. Specific examples of the aliphatic cyclic group include a group in which one or more hydrogen atoms have been removed from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. These may or may not be substituted with a lower alkyl group, a fluorine atom or a fluorinated alkyl group. Specifically, one or more hydrogen atoms are removed from monocycloalkanes such as cyclopentane and cyclohexane, and polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane! Etc. The tertiary alkyl group containing an aliphatic cyclic group includes, for example, a tertiary carbon on the ring skeleton of the aliphatic cyclic group such as the above-described 2-methyl-2-adamantyl group or 2-ethyl-2-adamantyl group. A group having an atom; a group in which a part of hydrogen atoms of a chain-like tertiary alkyl group is substituted with the above-mentioned aliphatic cyclic group.

 Examples of the tertiary alkyl group in the tertiary alkyloxycarbonyl group include the same strength S as described above. Specific examples of the tertiary alkyloxycarbonyl group include a tert-butyloxycarbonyl group and a tert-amyloxycarbonyl group. Specific examples of the cyclic ether group include a tetrahydrobiranyl group and a tetrahydrofuranyl group.

 [0014] In the present invention, in particular, the ability to form a high-resolution resist pattern and to reduce the roughness, the alkoxycarbonylalkyl group represented by the following general formula (pi) And at least one acid dissociable, dissolution inhibiting group selected from the group consisting of alkoxyalkyl groups represented by the following general formula (p2).

 [0015] [Chemical 5]

[Wherein R ¹ and R ² are each independently a linear, branched or cyclic alkyl group and may contain a hetero atom in the structure; R ³ is a hydrogen atom or a lower alkyl group; N ′ is an integer from !! to 3; ]

In the general formula (pi), n ′ is an integer of 1 to 3, and is preferably 1.

[0017] R ¹ is a linear, branched or cyclic alkyl group, and may contain a hetero atom in its structure. That is, in the alkyl group as R ¹ , some or all of the hydrogen atoms may be substituted with a group containing a hetero atom (including a hetero atom itself)! /, Or a carbon atom of the alkyl group Part of is replaced with a heteroatom! /, May! /

 Hetero atoms include oxygen atoms, sulfur atoms, nitrogen atoms, fluorine atoms, etc.

Yes The group containing a heteroatom may be a heteroatom itself or a group comprising a heteroatom and a carbon atom and / or a hydrogen atom, such as an alkoxy group.

 Examples of alkyl groups in which some or all of the hydrogen atoms are substituted with groups containing heteroatoms include, for example, carbon atoms in which some or all of the hydrogen atoms are substituted with fluorine atoms;! Lower alkyl group, a group in which two hydrogen atoms bonded to the same carbon atom are replaced with one oxygen atom (ie, a group having a carbonyl group (C = O)), two hydrogens bonded to the same carbon atom A group in which an atom is substituted with one sulfur atom (that is, a group having a thiocarbonyl group (C = S)), and the like.

 As a group in which a part of carbon atoms of the alkyl group is substituted with a group containing a hetero atom,

For example, an example in which a carbon atom is substituted with a nitrogen atom (for example, in the branched or cyclic alkyl group containing C H in the structure, CH— is substituted with NH

twenty two

 Substituted groups) or examples in which a carbon atom is substituted with an oxygen atom (for example, in a branched or cyclic alkyl group containing —CH 2 in its structure, the CH—

2 2 substituted groups).

[0018] The linear alkyl group as R ¹ preferably has 1 to 5 carbon atoms. Specifically, methyl, ethyl, n propyl, n butyl, isobutyl, n A pentynole group, preferably a methyl group or an ethyl group.

The branched alkyl group as R ¹ preferably has 4 to 10 carbon atoms, more preferably 4 to 8 carbon atoms. Specific examples include an isobutyl group, a tert butyl group, an isopentyl group, a neopentyl group, a tert pentyl group, and the like, preferably a tert butyl group.

[0019] The cyclic alkyl group as R ¹ preferably has 3 to 20 carbon atoms, more preferably 4 to 14 and more preferably force S, and most preferably 5 to 12.

The structure of the basic ring (basic ring excluding the substituent) in the cyclic alkyl group may be monocyclic or polycyclic. Particularly, the structure of the cyclic ring is preferable because it is excellent in the effects of the present invention. . The basic ring may be a hydrocarbon ring composed of carbon and hydrogen, or a heterocycle in which a part of carbon atoms constituting the hydrocarbon ring is substituted with a heteroatom. Yes. In the present invention, the basic ring is particularly preferably a hydrocarbon ring. Specific examples of the hydrocarbon ring include monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. Specific examples include monocycloalkanes such as cyclopentane and cyclohexane, and polycycloalkanes such as adamantane, norbornane, isobornane, tricyclic decane, and tetracyclododecane. Of these, adamantane, norbornane, tricyclodecane, and tetracyclododecane are preferred. Especially, adamantane is preferred! /.

 These basic rings may or may not have a substituent on the ring. Examples of the substituent include a lower alkyl group, a fluorine atom, a fluorinated lower alkyl group, an oxygen atom (= O) and the like. Examples of the lower alkyl group include straight-chain or branched alkyl groups having a carbon number of! To 5 such as a methyl group and an ethyl group. When the basic ring has a substituent, the number of substituents is preferably !!-3, more preferably 1. Here, “having a substituent” means that a hydrogen atom bonded to a carbon atom constituting the basic ring is substituted with a substituent.

Examples of the cyclic alkyl group for R ¹ include groups in which one hydrogen atom has been removed from these basic rings. R ¹ is preferably one of the carbon atoms constituting the basic ring as described above, to which the oxygen atom adjacent to R ¹ is bonded. In particular, the oxygen atom adjacent to R ¹ The carbon atom to be bonded is preferably a tertiary carbon atom to which a substituent such as a lower alkyl group is bonded, since the effect of the present invention is excellent.

Examples of the acid dissociable, dissolution inhibiting group having a cyclic alkyl group as R ¹ include groups represented by the following formulas (pi— ;!) to (pi-7). Among these, those represented by the general formula (pi-1) are preferable.

[Chemical 6]

[Wherein, R ⁴ is a lower alkyl group, and n is the same as described above. ]

[0021] The lower alkyl group of R ^{4 is} an alkyl group having 1 to 5 carbon atoms, and specifically includes a methylol group, an ethyl group, a propyl group, an isopropyl group, an nbutyl group, an isobutyl group, a tert- Examples thereof include a lower linear or branched alkyl group such as a butyl group, a pentyl group, an isopentyl group, and a neopentyl group. R ⁴ is more preferably a methyl group that is preferably a methyl group or an ethyl group in terms of industrial availability.

[0022] As R ^1, especially, preferred is the acid dissociable, dissolution inhibiting group having a cyclic alkyl group! /,.

In the formula (p2), examples of R ² include the same as R ¹ described above. Among them, R ² is preferably a linear alkyl group or a cyclic alkyl group.

R ³ is a hydrogen atom or a lower alkyl group. The lower alkyl group of R ^{3 is} an alkyl group having from 5 to 5 carbon atoms, specifically, methyl group, ethyl group, propyl group, isopropylene group, n butyl group, isobutyl group, tert butyl group, Examples include a lower linear or branched alkyl group such as a pentyl group, an isopentyl group, and a neopentyl group. As the hydrogen atom or the methyl group, a hydrogen atom that is preferable from the viewpoint of industrial availability is more preferable.

Examples of the group represented by the formula (p2) wherein R ² is a linear alkyl group include 1-ethoxyethyl group, 1 ethoxymethyl group, 1-methoxyethyl group, 1-methoxymethyl group, 1-methoxypropyl group. 1 ethoxypropyl group, 1 n butoxychetyl group, 1 pentafuryl group and the like. Examples of the group represented by the formula (p2) in which R ² is a cyclic alkyl group include a group represented by the following formula.

[0025] [Chemical 7]

'

^lo °

^l o °

[Wherein R ³ is the same as defined above. ]

Of these, a group represented by the following general formula (p2-1) or (p2-2) is preferable. [0027]

[式中、 は前記と同じであり、 n"および m"はそれぞれ独立に 0〜2の整数であり、 Wは 2原子の水素原子または酸素原子である。 ]

[In the formula, is the same as above, n ″ and m ″ are each independently an integer of 0 to 2, and W is a hydrogen atom or an oxygen atom of 2 atoms. ]

[0028] Most preferably, n "and m" are 0 or 1.

The bonding position between the adamantyl group and CHR ³ O 1 (CH) 1 is not particularly limited,

 2 n "

 Bonding to the 1-position or 2-position of the adamantyl group is preferred.

In the present invention, the acid dissociable, dissolution inhibiting group is a group represented by the above formulas (pi— ;!) to (pi-7), (p 2—;!) To (p2-2). As described above, a group having a cyclic group is also preferable because it can form a high-resolution resist pattern and can reduce roughness. When the acid dissociable, dissolution inhibiting group is a group having a cyclic group, the alkali solubility of the compound (A1) is lower than when the acid dissociable, dissolution inhibiting group is a chain group. Therefore, a resist film formed using a positive resist composition containing this compound (A1) has high resistance to an alkaline developer in an unexposed area.

 That is, the difference in alkali solubility (dissolution contrast) between the exposed area and the unexposed area is increased, and the resolution is improved.

 [0030] In addition, according to the present invention, by selecting the type of the acid dissociable, dissolution inhibiting group, the properties of the compound (A1), such as alkali solubility, can be adjusted. That is, in the compound (A1), when the acid dissociable, dissolution inhibiting group is introduced, the reactivity of the carboxy group is higher than that of the hydroxyl group, so that the acid dissociable, dissolution inhibiting group is introduced at the R ′ position. . For this reason, the structure of the portion other than R ′ is constant, and the variation in the structure between molecules is very small as compared with the polymer and the like conventionally used as the base component of the positive resist composition. Therefore, the properties of the compound (A1) as a whole can be adjusted by selecting the type of the acid dissociable, dissolution inhibiting group. For example, when a group having a polycyclic structure such as adamantane is selected as the acid dissociable, dissolution inhibiting group, when a group having a monocyclic structure such as cyclohexane is selected, or when a group having a chain structure is selected Then, the alkali solubility of the compound (A1) is a group having a chain structure having a monocyclic structure having a polycyclic structure.

In selecting the type of the acid dissociable, dissolution inhibiting group, it is particularly preferable to consider the structures of R ″ and R ^{U to} R ^17. This allows the alkali solubility of the compound (A1) to be determined according to the positive resist composition. For example, R "is a methyl group or the like. When it is a lower alkyl group having 1 to 5 carbon atoms and RU to R ¹⁷ is a chain alkyl group such as a methyl group, the compound (A1) tends to have a high alkali solubility S, acid dissociation By selecting a group having a polycyclic structure such as adamantane as the soluble dissolution inhibiting group, the alkali solubility of the compound (A1) can be lowered. Further, for example, when R ″ is an alkyl group having 6 to 10 carbon atoms and R ^{U to} R ¹⁷ are a cyclic alkyl group such as a cyclohexyl group or an aromatic hydrocarbon group, the compound (A1) Tends to be low in alkali solubility. At this time, by selecting and combining a group having a monocyclic structure such as cyclohexane as the acid dissociable, dissolution inhibiting group for R ′, the alkali of compound (A1) can be combined. Solubility can be increased.

[0031] R "is 1 to carbon atoms; 10, linear, branched or cyclic alkyl group, R ¹¹ - ^ 7 are each independently, carbon atoms;! A ~ 10 linear A branched or cyclic alkyl group or an aromatic hydrocarbon group.

 The alkyl group is preferably a linear or branched lower alkyl group having from 5 to 5 carbon atoms, or a cyclic alkyl group having 5 to 6 carbon atoms. 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, and a cyclohexyl group is preferable.

 Examples of the aromatic hydrocarbon group include a phenyl group, a tolyl group, a xylyl group, a mesityl group, a phenethyl group, and a naphthyl group.

The alkyl group or aromatic hydrocarbon group in R ^{U to} R ¹⁷ may contain a hetero atom such as an oxygen atom, a nitrogen atom, or a sulfur atom in its structure.

[0032] g and j are each independently an integer of 1 or more, k and q are each independently an integer of 0 or more, and g + j + k + q is 5 or less.

 g and j are preferably 1 or 2, most preferably 1.

k is preferably an integer of 0 to 2, and 0 or 1 is more preferable, and 1 is most preferable. q is preferably an integer of 0 to 2, and 0 or 1 is more preferable, and 0 is most preferable.

 [0033] a is an integer of 1 to 3, preferably 1 or 2, and most preferably 1.

 b is an integer of 1 or more, 1 and m are each independently an integer of 0 or more, and less than b + 1 + m force.

 b is preferably 1 or 2, most preferably 1.

 1 and m are preferably integers of 0 to 2, and 0 or 1 is more preferable, and 0 is most preferable.

 c is an integer of 1 or more, n and o are each independently an integer of 0 or more, and less than c + n + o force.

 c is preferably 1 or 2, most preferably 1.

 n and o are preferably integers of 0 to 2, and 0 or 1 is more preferable, and 0 is most preferable.

 [0034] The bonding position of the group [0— (CH) —CO—OR ′] with the subscript b or c is not particularly limited, but at least in the para position of A bonded to the benzene ring, O— (CH)

CO—OR ′ is preferably bonded. Such a compound has such advantages that a low molecular weight compound produced using this compound is suitable for a resist composition and that it is easy to synthesize.

 [0035] The bonding position of the hydroxyl group to which the subscript g is attached is not particularly limited! /, But a low molecular weight compound produced using the obtained compound is suitable for a resist composition. In view of ease, etc., it is preferably bonded to at least the para position (position 4) of the phenyl group.

The bonding positions of R ^u , R ^12, and R ¹⁷ are not particularly limited, but may be bonded to at least one of the carbon atoms adjacent to the carbon atom to which the hydroxyl group is bonded in terms of synthesis and the like. preferable.

 [0036] A is a group represented by the general formula (la), a group represented by the general formula (lb), or an aliphatic cyclic group.

In the formula (la), as the alkyl group or aromatic hydrocarbon group of R ¹⁸ and R ¹⁹ , the above ¹ to! ^ ^{1 The same as} the alkyl group or aromatic hydrocarbon group of ⁷ can be mentioned. Among these, as R ¹⁸ and R ¹⁹ , a methyl group is preferable from the viewpoint of reducing the roughness of the resist.

 r, y and z are each independently an integer of 0 or more, and r + y + z is 4 or less. Among them, it is preferable that r = l and y + z is 1.

[0037] The aliphatic cyclic group of A may have a substituent! /, May! /, And may / has! /.

 Examples of the substituent include a lower alkyl group having a carbon number of !! to 5, a fluorine atom, a fluorinated lower alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, an oxygen atom (= 0), 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.

 The “hydrocarbon group” is preferably a polycyclic group.

 Specific examples of such an aliphatic cyclic group include a group obtained by removing two or more hydrogen atoms from a monocycloalkane; two or more polycycloalkanes such as bicycloalkane, tricycloalkane, and tetracycloalkane. Examples include a group excluding a hydrogen atom. Specifically, a group in which two or more hydrogen atoms are removed from a monocycloalkane such as cyclopentane or cyclohexane, or two or more from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclodecane. And a group in which a hydrogen atom is removed.

 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, a group in which an aliphatic cyclic group having 4 to 15 carbon atoms is preferred and a hydrogen atom is removed from adamantane is more preferred. In particular, hydrogen atoms at the 1st and 3rd positions of adamantane are preferred. Groups other than are preferred.

[0038] As A, the group represented by the general formula (lb) is most preferable because it can be easily synthesized.

[0039] The compound (A1) of the present invention is particularly preferable because it is suitable for a resist composition produced using this compound, which is represented by the following general formula (A-2).

[0040] [Chemical 9]

OR 'OR'

ί ： —— i 'I i _e <

 (A-2)

During [0041] formula (A- 2), R ,, R ", R U ~R 12, a and A R ,, R in the formula ^{(A- 1)", R U} ~R 12, a and A It is the same. b 'is an integer of 1 to 4, 1 or 2 is preferred, and 1 is most preferred. c ′ is an integer of 1 to 4, 1 or 2 is preferred, and 1 is most preferred.

Among these, a compound in which b ′ and c ′ are 1 is particularly preferable, and a compound represented by the following general formula (A-2-1) is preferable. In the formula (A-2), R ′ is a hydrogen atom or an acid dissociable, dissolution inhibiting group, and the plurality of R ′ may be the same or different from each other, and at least of the plurality of R ′. Some are acid dissociable, dissolution inhibiting groups; R "is an alkyl group having 1 to 10 carbon atoms; R ^{U to} R ¹² are each independently 1 to 10 carbon atoms; an alkyl group having 10 or aromatic hydrocarbons A group which may contain heteroatoms in its structure; a is an integer from 1 to 3; b ′ is an integer from 1 to 4; c ′ is an integer from 1 to 4; A group represented by the general formula (la), a group represented by the general formula (lb), or an aliphatic cyclic group.

[0042] [Chemical 10]

 (A 2 1 1)

[Wherein, R ′, R ″, R ^{U to} R ¹² , a and A are the same as described above.]

[0043] The bonding position of R ¹² is not particularly limited, but is preferably bonded to the OR position or the meta position of the OR '' group in terms of synthesis, etc.! /, .

 That is, the compound represented by the formula (A-2) includes the following general formula (A-2-2) or (

A— 2— The compound represented by 3) is preferred!

[0044] [Chemical 11]

[Wherein R, R ", R to R a, b, c 'and A are the same as above.] [Chemical 12]

(A-2-3) [Wherein R, R ", R ^{U to} R ¹² , a, b, c 'and A are the same as described above.]

[0046] The compound (A1) is preferably a material capable of forming an amorphous film by spin coating. Here, an amorphous film means an optically transparent film that does not crystallize. The spin coating method is one of the commonly used thin film formation methods. Whether this compound is a material that can form an amorphous film by the spin coating method is determined by spin coating on an 8-inch silicon wafer. It can be determined by whether or not the coating film formed by the method is completely transparent. More specifically, for example, the determination can be made as follows. First, a solvent generally used as a resist solvent is mixed with this compound, for example, a mixed solvent of ethyl lactate / propylene glycol monomethyl ether acetate = 40/60 (mass ratio) (hereinafter abbreviated as EM). ) Is dissolved to a concentration of 14% by mass, subjected to ultrasonic treatment (dissolution treatment) using an ultrasonic cleaner, and this solution is spun on a wafer at 1500 rpm. Coat and dry bake (PAB, Post Applied Bake) at 110 ° C for 90 seconds. Under this condition, it is visually checked whether an amorphous film is formed depending on whether it is transparent or not. Check. Note that a cloudy film that is not transparent is not an amorphous film.

 In the present invention, it is preferred that the compound (A1) is stable in the amorphous film formed as described above. For example, after the PAB, the amorphous film is amorphous even after being left in a room temperature environment for 2 weeks. The state is maintained!

 [0047] The compound (A1) is a compound represented by the following general formula (Π), wherein a part or all of the hydrogen atoms at the phenolic hydroxyl terminal of the compound (Π) are substituted by a well-known method with 1 to 10 carbon atoms. It can be produced by substitution with an alkyl group (R ").

[0048] [Chemical 13]

 ■)

[In the formula (II), R, R ^{U to} R ¹⁷ , g, j, k, q, a, b, 1, m, c, n, o and A are respectively represented by the above formulas (A-1 ), R, R ^{U to} R ¹⁷ , g, j, k, q, a, b, 1, m, c, n, o and A are the same. ]

 [0049] In the compound (Π), a part or all of the hydrogen atoms at the carboxy group terminal of the compound (I) represented by the following general formula (I) are converted to acid dissociable, dissolution inhibiting groups by a known method. Manufacture by replacement.

[0050] [Chemical 14]

 (1)

[In the formula (I), R ^{U to} R ¹⁷ , g, j, k, q, a, b, 1, m, c, n, o and A are respectively R in the above formula (A-l). ^{U to} R ¹⁷ , g, j, k, q, a, b, 1, m, c, n, o and A are the same. Compound (I) can be produced by a conventionally known method. For example, two salicylaldehydes (having a substituent! /, May! /) Are bonded via A as described above. A tris (hydroxyphenyl) methane derivative is obtained by dehydrating and condensing a salicylaldehyde derivative and a substituted phenolic compound under acidic conditions, and the tris (hydroxyphenyl) methane derivative has a hydroxyl group. It can be produced by introducing a carboxyalkyloxy group by reacting a halogenated carboxylic acid such as a bromoacetate derivative. However, in such a conventionally known method, it is difficult to control the position and number of the hydroxyl group into which the carboxyalkyloxy group is introduced. A carboxyalkyloxy group is attached to each of the two benzene rings bonded via A. There is a problem that the yield of the bound compound (I) is low.

 Therefore, the compound (I) is obtained by reacting the compound (I 1) represented by the following general formula (I 1) with the compound (I 2) represented by the following general formula (I 2). A step of obtaining the compound (1 3) represented by I 3) (hereinafter referred to as the compound (1 3) formation step! /, U),

A step of obtaining compound (I) through a step of reacting compound (I 3) and compound (I 4) represented by the following general formula (I 4) under acidic conditions (hereinafter referred to as compound (I) formation step) And les) Preferably manufactured by a manufacturing method having:

[Chemical 15]

[Wherein X is a halogen atom; R is a protecting group; R 1 to R 4, g, j, k, q, a, b, 1, m, c, n, o and A are respectively R ^{U to} R ¹⁷ , g, j, k, q, a, b, 1, m, c, n, o and A in formula (I) are the same. ]

<Compound (I 3) formation process>

In general formula (I 1 ;!) to (1-3), R ^{13 to} R ¹⁶ , a, b, 1, m, c, n, o and A are the same as R ¹³ to R ¹³ in general formula (I) above. Same as R ¹⁶ , a, b, 1, m, c, n, o and A.

 In general formula (I2), examples of the halogen atom for X include a bromine atom, a chlorine atom, and a fluorine atom. A bromine atom is preferable because of excellent reactivity.

The protecting group for R does not react when reacting compound (I 1) with compound (I 2), and reacts with compound (I 3) in the next compound (I) formation step. Solution under acidic conditions The group is not particularly limited as long as it is an acid-dissociable group that can be released, and can be arbitrarily selected from those generally proposed as a protecting group.

 Examples of the protecting group include those similar to those exemplified as the acid dissociable, dissolution inhibiting group for R ′ in the above formula (A-1).

As the protective group for R, a tertiary alkyl group or an alkoxyalkyl group is preferred because it is easily dissociated by an acid and is easily available. Alkyl group; in the formula (p2), R ² — may be a linear or branched alkyl group, and the structure may contain a heteroatom. R ³ may be a hydrogen atom or a linear or branched group. A chain tertiary alkyl group is preferred, and a tert butyl group is most preferred.

[0054] Compound (I 1) and compound (I 2) can be reacted by a known method. For example, compound (I 1) is dissolved in an organic solvent such as acetone, and carbonic acid is dissolved in the solution. The reaction can be carried out by adding a base such as potassium and adding about 2 equivalents of compound (12) to the compound (1-1) to be used in the solution while stirring.

 As the organic solvent to be used at this time, any organic solvent can be selected as long as it dissolves the compounds (I 1) and (I 2) and the compound (I 3) to be formed. That's fine. Common organic solvents include, for example, ketones such as acetone, methyl ethyl ketone, methinoleamino ketone, and cyclohexanone; ethers such as THF, dioxane, gram, and propylene glycol monomethyl ether; Examples include estenoles such as chinole; etherolesters such as propyleneglycolole methinoreethenoreacetate; and 7 latatones such as butyrolatataton, which can be used alone or in admixture.

 The reaction temperature is preferably 10 to 60 ° C, and more preferably 20 to 60 ° C. Usually, the reaction temperature may be about room temperature (20 to 25 ° C).

 The reaction time is preferably;! To 24 hours, preferably 4 to 15 hours.

[0055] After completion of the reaction, the reaction solution may be used in the next step as it is, but water / ethyl acetate and the like are added, and the organic phase (ethyl acetate phase, etc.) is concentrated under reduced pressure to obtain compound (13). May be.

[0056] <Compound (I) formation step> In general formula (I-4), ¹ , R ¹ R ", g, j, k and q are R ¹¹ , R ¹² , R ¹⁷ , g, j, k and q in the above formula (I), respectively. It is the same.

 In this step, first, the step of reacting the compound (I 3) and the compound (I 4) under acidic conditions is performed. As a result, the formyl group (one CHO) of the compound (13) reacts with the compound (14), and the protecting group R of the compound (I3) dissociates to form a carboxy group. Specifically, for example, about 4 equivalents of the compound (I 4) is dissolved in an organic solvent such as methanol, and an acid such as hydrochloric acid is added to the solution. The reaction can be carried out by adding compound (I3) to this mixed solution.

 The acid used at this time is not particularly limited as long as compound (I 3) and compound (I 4) react with each other and protecting group R dissociates. Preferred examples include hydrochloric acid, sulfuric acid, sulfuric anhydride, p-toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, oxalic acid, formic acid, phosphoric acid, trichloroacetic acid, trifluoroacetic acid and the like. wear. In particular, hydrochloric acid is preferably used. These acids may be used alone or in combination of two or more.

 For example, in the case of 35% by mass hydrochloric acid, the acid is added in an amount of 1 to 700 parts by mass, preferably 100 to 600 parts by mass with respect to 100 parts by mass of the compound (I3).

 The reaction temperature is preferably 20 to 80 ° C, more preferably 30 to 65 ° C.

 The reaction time is preferably 2 to 96 hours, more preferably 5 to 72 hours.

 After completion of the reaction, a base such as sodium hydroxide is added to the reaction solution to neutralize the acid in the reaction solution. At this time, for example, when an alcohol such as methanol is used as the organic solvent used in the reaction solution, the resulting carboxy group may be slightly esterified with the alcohol. Therefore, it is preferable to add an excess base in order to hydrolyze the ester.

In the reaction solution thus obtained, compound (I) is dissolved as a salt. Therefore, for example, the reaction solution is transferred to a separatory funnel and washed with water / jetyl ether or the like to remove raw materials (compounds used in the reaction, etc.), and then the aqueous layer is extracted and neutralized with an aqueous hydrochloric acid solution. Precipitation occurs. By collecting this precipitate by filtration or the like, compound (I) can be obtained. This unpurified compound (I) may be further subjected to a purification treatment such as reprecipitation.

[0058] As described later, the compound (A1) contains a base component (A) whose alkali solubility is increased by the action of an acid, and an acid generator component (B) that generates an acid upon irradiation with radiation. The positive resist composition can be suitably used as the substrate component (A).

 By using a positive resist composition containing the compound (A1), a resist pattern with high resolution, for example, an ultrafine resist pattern having a pattern dimension of 200 nm or less can be formed, and the strength and roughness can be reduced.

 This is presumed to be due to the uniformity of the compound (A1). That is, it is difficult to control molecular weight dispersion and alkali-soluble dispersion in conventional resists using a high molecular weight polymer (resin) as a base material component of the resist material. For this reason, there is a limit to the reduction of LER caused by these dispersions and the molecular size itself.

 In addition, low molecular weight compounds considered as a solution to the above problem also protect alkali-soluble groups with acid-dissociable, dissolution-inhibiting groups as described in Non-Patent Documents 1 and 2 above. However, there is a variation in the position of the alkali-soluble group to be protected and the protection ratio thereof for each molecule. As a result, the properties also vary, resulting in the same problem as described above. On the other hand, compound (A1) has a low It is a non-polymer of molecular weight. In addition, as described above, the compound (I) used for the production has a phenolic hydroxyl group and a carboxyl group as alkali-soluble groups, and the alkali-soluble group is protected by an acid dissociable, dissolution inhibiting group. The more reactive carboxy group is selectively protected. Therefore, the resulting compound (A1) has less variation in its structure and molecular weight than when, for example, an equivalent amount of only a hydroxyl group as an alkali-soluble group is present. Therefore, compound (A1) has little variation in properties such as alkali solubility and hydrophilicity / hydrophobicity for each molecule, and can form a resist film with uniform properties. Therefore, it is presumed that by using the compound (A1), a resist film having a uniform property can be formed, whereby a high-resolution resist pattern can be formed and roughness can be reduced.

[0059] Further, as described above, since the property of compound (A1) is uniform and it is considered that a resist film having uniform properties (alkali solubility, hydrophilicity, hydrophobicity, etc.) can be formed, compound (A1 ) By using, the diffet can be reduced. Here, the differential is, for example, a general defect detected when a developed resist pattern is observed from directly above with a surface defect observation device (trade name “KLA”) manufactured by KLA Tencor. Examples of this defect include scum after development, bubbles, dust, bridges between resist patterns, uneven color, precipitates, etc. Also, the properties of compound (A1) are uniform and the solubility in organic solvents is uniform. Therefore, the storage stability of the positive resist composition containing the compound (A1) is also improved.

 <Positive resist composition>

 The positive resist composition of the present invention comprises a base material component (A) (hereinafter referred to as the (A) component) that increases the solubility of an alcohol by the action of an acid, and an acid generator that generates an acid upon irradiation with radiation. Component (B) (hereinafter referred to as component (B)) is contained, and compound (A1) is contained as component (A).

 In a positive resist composition containing the component (A) and the component (B), when the acid generated from the component (B) by exposure acts on the component (A), the entire component (A) is reduced in strength. It changes from insoluble to alkali-soluble. Therefore, in the formation of the resist pattern, when the resist film made of the positive resist composition is selectively exposed or heated after exposure in addition to the exposure, the exposed portion becomes alkali-soluble, while the unexposed portion Since it remains insoluble in alkali and does not change, positive resist pattern can be formed by alkali development.

[0061] [(A) component]

 The component (A) contains the compound (A1).

 As the compound (A1), one type may be used alone, or two or more types may be used in combination.

 In the component (A), the proportion of the compound (A1) is preferably more than 40% by mass, more preferably more than 50% by mass, and more preferably more than 80% by mass, most preferably 100% by mass. %.

The proportion of compound (A1) in component (A) can be measured by means such as reverse phase chromatography. [0062] The component (A) is further proposed as a base component of a chemically amplified resist so far as it does not impair the effect of using the compound (A1)! In the following, (A2) and ingredients may be included! /!

 Examples of the component (A2) include those proposed as base resins such as conventional chemically amplified positive resist compositions for KrF and positive resist compositions for Ar F! / It can be suitably selected according to the type of exposure light source used at the time of formation.

 [0063] The content of the component (A) in the positive resist composition may be adjusted according to the resist film thickness to be formed.

 [0064] [(B) component]

 The component (B) is not particularly limited, and it is possible to use what has been proposed as an acid generator for chemically amplified resists.

 Examples of such acid generators include onium salt acid generators such as odonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, There are various known diazomethane acid generators such as poly (bissulfonino) diazomethanes, nitrobenzyl sulfonate acid generators, iminosulfonate acid generators, and disulfone acid generators.

 [0065] Examples of the onium salt-based acid generator include an acid generator represented by the following general formula (b-0).

 [0066] [Chemical 16]

[Wherein R ⁵¹ represents a linear, branched or cyclic alkyl group, or a linear, branched or cyclic fluorinated alkyl group; R ⁵² represents a hydrogen atom, a hydroxyl group, a halogen atom, a straight Chain or branched alkyl group, linear or branched alkyl halide group

Or a linear or branched alkoxy group; R ⁵³ is an aryl group which may have a substituent; u ″ is an integer of 1 to _3. ] In the general formula (b-0), R ⁵¹ 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 still more preferably 1 to 4 carbon atoms. . The cyclic alkyl group preferably has 4 to 12 carbon atoms, preferably 5 to 10 carbon atoms, more preferably 6 to 10 carbon atoms, and most preferably 10 to 10 carbon atoms.

 The fluorinated alkyl group preferably has 1 to 10 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 4 carbon atoms. Also. The fluorination rate of the alkyl fluoride 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%. Particularly, all hydrogen atoms are substituted with fluorine atoms. This is preferable because the strength of the acid is increased.

R ⁵¹ is most preferably a linear alkyl group or a fluorinated alkyl group.

[0068] ^R52 represents a hydrogen atom, a hydroxyl group, a halogen atom, a linear, branched or cyclic alkyl group, a linear or branched alkyl halide group, or a linear or branched ananoloxy group. is there.

In R ⁵² , 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 ⁵² , when the alkyl group is linear or branched, the carbon number thereof is preferably 1 to 5, particularly preferably !! to 4, and more preferably 1 to 3. When R ⁵² is a cyclic alkyl group, it is preferably a carbon number power of ~; 12 is preferably 5 to 10; more preferably 10 to 10 is most preferable.

In R ⁵² , 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 include the same forces S as the linear or branched “alkyl group” in R ⁵² . Examples of the halogen atom to be substituted include the same “halogen atom” as described above. In the halogenated alkyl group, 50 to 100% of the total number of hydrogen atoms must be substituted with halogen atoms. More preferably, all desired substitutions are made.

In R ⁵² , the alkoxy group is linear or branched, and the carbon number thereof is preferably 1 to 5, particularly preferably !! to 4, and more preferably 1 to 3.

Among these, R ⁵² is preferably a hydrogen atom.

[0069] R ⁵³ has a substituent! /, May! /, An aryl group, and the structure of the basic ring (matrix ring) is a naphthyl group, a phenyl group, or a basic ring (base ring). And anthracenyl group. From the viewpoint of the effect of the present invention and the 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 chain or branched chain, preferably having 5 or less carbon atoms, particularly preferably a methyl group).

The aryl group of R ⁵³ has no substituent! /, More preferably! / ,.

 u "is an integer of 1 to 3, 2 or 3 is preferred and 3 is particularly desirable.

 [0070] Preferable examples of the acid generator represented by the general formula (b-O) include those represented by the following chemical formulas.

[0071] [Chemical 17]

[0072] The acid generator represented by the general formula (b-0) can be used alone or in combination of two or more.

[0073] Other onium salt acid generators of the acid generator represented by the general formula (b-0) include, for example, compounds represented by the following general formula (b-1) or (b-2) Can be mentioned. [Chemical 18]

ル基を表し、 R' 〜R⁶"のうち少なくとも 1つは ァリール基を表す。 ] [Wherein, ,, to “, 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 a fluorinated alkyl group; Representation;

And at least one of R ′ to R ⁶ ″ represents an aryl group.]

In formula (b— 1), ¹ “˜! ^” Each independently represents an aryl group or an alkyl group. R ~ ³ "represents at least one aryl group. Of ¹ " ~! ^ ³ ", two or more are preferably aryl groups. All" ~ "are aryl groups. Is most preferred

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

 Examples of the alkyl group on which the hydrogen atom of the aryl group may be substituted are a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group, which are preferably alkyl groups having 1 to 5 carbon atoms. It is most preferred! /

 As the alkoxy group, a methoxy group and an ethoxy group are preferred, and an alkoxy group having! To 5 carbon atoms is preferred.

 When the hydrogen atom of the aryl group is substituted! /, The halogen atom is preferably a fluorine atom.

R1 as alkyl group "to R ^3", Nag particularly limited for example, the number of carbon atoms;! A ~ 10 linear

And a branched or cyclic alkyl group. From the viewpoint of excellent resolution, the number of carbon atoms is preferably 1 to 5. Specifically, methyl group, ethyl group, n-propyl group, isop Examples include pill group, n-butyl group, isobutyl group, n-pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, nonyl group, decanyl group, etc. It is preferable because it is possible, and it is possible to list methyl groups as things.

Of these, ¹ "~! ^" Is most preferably a phenyl group.

[0076] R ⁴ "represents a linear, branched or cyclic alkyl group or fluorinated alkyl group.

 The linear alkyl group is most preferably 1 to 4 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 4 carbon atoms.

The cyclic alkyl group is a cyclic group as indicated by R ¹ ″ and preferably has 4 to 10 carbon atoms, more preferably 4 to 10 carbon atoms. Most preferably, it has 6 to 10 carbon atoms.

 The fluorinated alkyl group preferably has 1 to 10 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 4 carbon atoms. Also. The fluorination rate of the alkyl fluoride group (the ratio of fluorine atoms in the alkyl group) is preferably 10 to 100%, more preferably 50 to 100%, and in particular, all hydrogen atoms are placed as fluorine atoms. The one converted is preferable because the strength of the acid is increased.

R ⁴ ″ is most preferably a linear or cyclic alkyl group or a fluorinated alkyl group.

In the 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. Most preferably, all of R ⁵ "to R ⁶ " are aryl groups.

Examples of R ⁵ "~ R ⁶ " arele groups are the same as those for ¹ "~! ^"

Yes

Examples of the alkyl group for R ⁵ ″ to R ⁶ ″ include the same as the alkyl group for Rl ″ to R ³ ″.

Among these, it is most preferable that all of R ⁵ ″ to R ⁶ ″ are phenyl groups. "The R ⁴ in the formula (b-1)" Formula (b-2) R ⁴ in the same groups as those described above for.

[0078] Specific examples of the onium salt-based acid generators represented by the formulas (b-1) and (b-2) include diphenols. Bis (4 tert butylphenyl) odonitrium trifluoromethanesulfonate or

Norefonate, tri (4 methylphenyl) sulfurium trifluoromethanesulfonate,

Triphenylmethanesulfonate of monophenyldimethylsulfone, its heptafunole sulfonate, or its nonafluorobutane sulfonate, (4 methylphenol) diphenylate or its nonafluorobutane sulfonate, (4-methoxyphenyl) diphenyl Or its nonafnorenobutanesulfonate, tri (4 tert butynole) phenenolesnore or its nonafrobutanesulfonate, diphenyl (1 (4-methoxy) naphthyl) ate or its nonafrobutanesulfonate Is mentioned. Further, 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.

 [0079] Further, in the general formula (b-1) or (b-2), an anion salt system in which the anion part is replaced with an anion part represented by the following general formula (b-3) or (b-4) An acid generator can also be used (the cation moiety is the same as (b-1) or (b-2)).

 [0080] [Chemical 19]

… (

[式中、 X"は、少なくとも 1つの水素原子がフッ素原子で置換された炭素数 2〜6のァ ノレキレン基を表し; Υ"、 Ζ"は、それぞれ独立に、少なくとも 1つの水素原子がフッ素 原子で置換された炭素数;!〜 10のアルキル基を表す。 ]

[In the formula, X "represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom; Υ" and Ζ "are each independently at least one hydrogen atom is fluorine. The number of carbon atoms substituted with an atom; represents an alkyl group having! -10.

[0081] 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 3 carbon atoms. 5, most preferably 3 carbon atoms.

 Υ "and Ζ" 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 Has 1 to 7 carbon atoms, more preferably 1 to 3 carbon atoms.

 The carbon number of the alkylene group of X ″ or the carbon number of the alkyl group of “ア ル キ ル” and “Ζ” is preferably as small as possible within the range of the above-mentioned carbon number for reasons such as good solubility in a resist solvent.

 In addition, in the alkylene group of X "or the alkyl group of Υ" and Ζ ", the greater the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength and the higher the energy 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%. Most preferably, it is a perfluoroalkylene group or a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms.

In the present specification, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), which generates an acid upon irradiation with radiation. It is what has. Such oxime sulfonate acid generators are widely used for chemically amplified resist compositions, and can be arbitrarily selected and used.

Yes

 [0083] [Chemical 20]

—— C— N— 0— SOg "-" -R ³¹

R ^j2 , ', CB-1)

(In the formula (B-1), R ³¹ and R ³² each independently represents an organic group.) The organic group of [0084] 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 (fluorine atom, chlorine atom, etc.)). You may do it.

As the organic group for R ³¹ , a linear, branched or cyclic alkyl group or aryl group is preferable. These alkyl groups and aryl groups may have a substituent. The substituent is not particularly limited, and examples thereof include a fluorine atom, a linear, branched or cyclic alkyl group having 6 to 6 carbon atoms. 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.

Yes

 As the alkyl group, carbon number 1 to 20 is preferable 1 to 10; carbon number 10 is more preferable 1 to 8 is more preferable;! To 6 is particularly preferable carbon number 1 to 4 is most preferred. 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 the hydrogen atoms are halogen atoms. It means an alkyl group substituted by. Examples of the halogen atom include a fluorine atom, a chlorine atom, an fluorine 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 is most preferably 4 to 20 carbon atoms, preferably 4 to 20 carbon atoms; and more preferably 6 to 10 carbon atoms, more preferably 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. A partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is substituted with a halogen atom, and a fully halogenated aryl group means that all hydrogen atoms are halogenated. An aryl group substituted with an atom.

R ³¹ is particularly preferably an alkyl group having 1 to 4 carbon atoms having no substituent or a fluorinated alkyl group having 1 to 4 carbon atoms! /.

As the organic group for R ³² , a linear, branched or cyclic alkyl group, aryl group or cyan group is preferable. Examples of the alkyl group and aryl group for R ³² include the same alkyl groups and aryl groups as those described above for R ³¹ . R 1 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.

[0086] As the oxime sulfonate-based acid generator, more preferred are those represented by the following general formula (

Examples thereof include compounds represented by B-2) or (B-3).

[0087] [Chemical 21]

[In the formula (Β-2), R ³³ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁴ is an aryl group. R ³⁵ represents an alkyl group having no substituent or a halogenated alkyl group. ]

[0088] [Chemical 22]

[In the formula (B-3), R ³⁶ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁷ is a divalent or trivalent aromatic hydrocarbon group. R ³⁸ is an alkyl group having no substituent or a halogenated alkyl group. p "is 2 or 3.]

[0089] In the general formula (B-2), the alkyl group or halogenated alkyl group having no substituent for R ³³ preferably has 1 to 10 carbon atoms, and preferably has 1 to 8 carbon atoms. Is more preferred. Carbon number 1 to 6 is most preferred.

R ³³ is more preferably a fluorinated alkyl group, preferably a halogenated alkyl group.

Yes

The fluorinated alkyl group for R ³³ preferably has 50% or more of the hydrogen atom of the alkyl group, more preferably 70% or more, and even more preferably 90% or more. .

[0090] The aryl group of R ^{34 includes} an aromatic group such as a phenyl group, a biphenyl group, a fluorenyl group (f 1 uorenyl) group, a naphthyl group, an anthracyl group, and a phenanthryl group. A group obtained by removing one hydrogen atom from a ring of a group hydrocarbon and a hetero atom in which a part of the carbon atoms constituting the ring of these groups is substituted with a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom. And a roaryl group. Among these, a fluorenyl group is preferable.

The aryl group of R ³⁴ 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 is preferably 1 to 4 carbon atoms, more preferably 1 to 8 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.

[0091] The alkyl group or halogenated alkyl group having no substituent of R ³⁵ has carbon number;

 A carbon number of 1 to 6 which is preferably 10 is most preferable, and a carbon number of 1 to 6 is more preferable.

R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group, and more preferably a partially fluorinated alkyl group.

The fluorinated alkyl group in R ³⁵ preferably has a hydrogen atom of the alkyl group of 50% or more fluorinated, more preferably 70% or more, and still more preferably 90% or more. This is preferable because the strength of the generated acid is increased. Most preferably, it is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted.

[0092] In the general formula (B-3), the alkyl group or halogenated alkyl group having no substituent of R ³⁶ does not have the substituent of R ³³ ! /, An alkyl group or a halogenated group Examples are the same as the alkyl group.

Examples of the divalent or trivalent aromatic hydrocarbon group for R ³⁷ include groups obtained by further removing 1 or 2 hydrogen atoms from the aryl group for R ³⁴ .

Examples of the alkyl group or halogenated alkyl group having no substituent of R ³⁸ include those similar to the alkyl group or halogenated alkyl group having no substituent of the above ⁵ .

 P "is preferably 2.

[0093] Specific examples of the oxime sulfonate acid generator include α (p-toluenesulfonyloxyimino) benzylcyanide, α (ρ chlorobenzenesulfonyloxyimino) benzylcyanide, α- (4 Benzenesulfonyloxymino) Benzyl cyanide, α (4 12 tallow 2 trifluoromethylbenzenesulfonyloxymino) Benzylcyanide, α (Benzenesulfonyloxyimino) -4 Chronobenzoylcyanide, α- (Benzenesulfonyloxyimino) -2, 4-Dichlorocylbenzylocyanide, α (Benzenesulfonyloxyimino) )-2, 6-Dichlorodiphenylcyanide, α (Benzenesulfonyloxyximino) -4-methoxybenzylcyanide, α (2 Dichlorodiphenylsulfonylcyanide) 4-methoxybenzylcyanide , Α (Benzenesulfonoxyximino) Chen-2-ylacetonitrile, α (4-dodecylbenzenesulfonoxyximino) benzyl cyanide, α [(ρ Toluenesulfonyloxymino) 4-methoxyphenoxy] acetonitrile, α [(dodecyl Benzenesulfonyloxyimino) 4-methoxyphenyl] acetonitrile, a (Tosyl Simino) -4 cenyl cyanide, α (methylsulfonyloxyimino) 1-cyclopentenylacetonitrile, α (methylsulfonyloxyimino) 1-cyclohexenylacetonitrile, a (methylsulfonyloxyimino) 1 over cycloheptenylidenephenyl Saturation Rua Seto nitrile, alpha (Mechirusuruho Niruokishiimino) -1-cyclopropyl OTA Saturation Rua Seto nitrile, alpha (triflate Ruo b methylsulfanyl Honi Ruo key Consequences amino) 1 Shikuropente two Ruasetonitoriru, _alpha (triflate Ruo b methyl scan Ruhoniru Oxyimino) -cyclohexylhexonitrile, α (ethylsulfonyloxyimino) -ethylacetonitrile, a (propylsulfonyloxyimino) propylacetontrinore, α (cyclohexylsulfonyloxyximino) ) -Cyclopentylacetoni Linole, α (Cyclohexylsulfonyloximino) -Cyclohexylacetonitrile, a (Cyclohexylsulfonyloximino) 1-Cyclopentenylrucetonitrile, a (Ethylsulfonyloxyximino) 1-Cyclopentenylrucetonitrile , Α- (isopropylpropyloxymino) 1-cyclopentenylacetonitrile, α- (η-butylsulfonyloxymino) 1-cyclopentenylacetonitrile, α (ethylsulfonyloxymino) 1-cyclohexenyl Cetonitrile, α (isopropylsulfonyloxymino) 1-cyclohexenylacetonitrile, α- (η butylsulfonyloxyimino) 1-cyclohexenylacetonitrile, α (methylsulfonyloxyimino) phenylenoreacetonitriole, α (methylsulfonyloxyimino) ρ methoxyphenylacetonitrile, a (trifluoromethylsulfonyloxyimino) phenylacetonitrile, _a (trifluoromethylsulfonyloxyimino) p methoxyphenyl Acetonitrile, α (ethylsulfonyloxyimino) ρ methoxyphenylacetonitrile, α- (propylsulfonyloxyimino) ρ methylphenylacetonitrile, α (methylsulfonyloxyimino) ρ bromophenylnitrile, etc. Further, an oxime sulfonate acid generator disclosed in JP-A-9 208554 (paragraphs [0012] to [0014] [Chemical 18] to [Chemical 19]), WO2004 / 074242A2 (pages 65 to 85) An oxime sulfonate-based acid generator disclosed in Example of the eyes;!-40) can also be suitably used.

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

[Chemical 23]

上記例示化合物の中でも、下記の 4つの化合物が好ましい 24]

Of the above exemplified compounds, the following four compounds are preferred 24]

[0097] Among diazomethane acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis (isopropylsulfonyl) diazomethane, bis (p-toluenenorenonino) diazomethane, bis (1, 1 -Dimethinoleethinoresnorehoninore) diazomethane, bis (cyclohexenolesnorehoninore) diazomethane, bis (2,4 dimethinolefuinorenorehoninore) diazomethane, and the like.

 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) pronone, 1,4-bis (disclosed in JP-A-11 322707. Fenenolesno rehonino regiozome chinore les nore hononole) butane, 1, 6-bis (fuenino les reno zoino linole reno inno re) hexane, 1, 10-bis Phonyldiazomethylsulfoninole) decane, 1,2-bis (cyclohexylsulfonyldiazomethylsulfoninole) ethane, 1,3-bis (cyclohexylsulfonyldiazomethylsulphoninole) propane, 1, 6-bis (cyclohexylenoresnorenoinoresinazomethinolesnorehoninole) hexane, 1,10-bis (cyclohexylsulfonyldiazomethylsulfo) Norre) decane, and so on can be force S mentioned.

 [0098] As the component (B), one type of these acid generators may be used alone, or two or more types may be used in combination.

The content of the component (B) in the positive resist composition is preferably 0.5 to 30 parts by mass with respect to 100 parts by mass of the component (A); more preferably 15 to 15 parts by mass. Pattern formation is sufficiently performed when the amount falls within the above range. Further, it is preferable because a uniform solution can be obtained and the storage stability becomes good. [0099] [Optional components]

 The positive resist composition further contains optional components to improve the resist pattern shape, post expo sure stability of the latent image formed by tne pattern-wise exposure of the resist 1 ayer, etc. As a nitrogen-containing organic compound (D) (hereinafter referred to as component (D)) can be added.

 A wide variety of components (D) have already been proposed, and any known one can be used. For example, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, etc. Dialkylamines such as jetylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, dicyclohexyl-lamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, trie n-hexylamine, tri-n-pentylamine, tri-n-heptinoleamine, tri-n-year-old cutinoleamine, tri-n non-no-leamine, tri-n-demethylamine, tri-n-dodecylamine, etc .; diethanolamine, triethanolamine, diisopro Noruamin, triisopropanolamine § Min, di n OTA Tanoruamin, alkyl alcohols § Min and triethylene n O click pentanol § Min like et be. Among these, in particular, secondary aliphatic amines are preferred, and tertiary aliphatic amines are preferred, and tri-octylamine is most preferred, with trialkylamines having 5 to 10 carbon atoms being more preferred.

 These can be used alone or in combination of two or more.

 Component (D) is usually used in the range of 0.01 to 5.0 parts by mass per 100 parts by mass of component (A).

 [0100] In the positive resist composition, for the purpose of preventing sensitivity deterioration due to the blending of the component (D), and improving the resist pattern shape, stability with time, etc., an organic carboxyl group is further added as an optional component. An acid or phosphorus oxoacid or a derivative thereof (E) (hereinafter referred to as component (E)) can be included. In addition, the component (D) and the component (E) can be used in combination, or any one of them can be used.

As the organic carboxylic acid, for example, malonic acid, citrate, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable. Phosphorus acid or its derivatives include phosphoric acid Phosphoric acid, phosphonic acid dimethyl ester, phosphonic acid mono-butynoreestenole, phenylenophosphonic acid, phosphone Derivatives such as phosphonic acid and their esters such as diphenenolesthenolic acid and phosphonic acid dibenzyl ester, phosphinic acids such as phosphinic acid and phenylphosphinic acid, and derivatives thereof Of these, phosphonic acid is particularly preferred.

 Component (E) is used at a ratio of 0.01 to 5.0 parts by mass per 100 parts by mass of component (A).

[0101] In the positive resist composition, if desired, there are further miscible additives such as an additional resin for improving the performance of the resist film, a surfactant for improving the coating property, and a dissolution inhibitor. , Plasticizers, stabilizers, colorants, antihalation agents, dyes, etc. are added as appropriate.

 [0102] The positive resist composition may be made of an organic solvent (hereinafter referred to as "(S) component").

 ) And can be produced.

 As the component (S), it is sufficient if each component to be used can be dissolved into a uniform solution. Any one of conventionally known solvents for chemically amplified resists can be used. Two or more kinds can be appropriately selected and used.

For example, latatones such as γ-butyrolatatane; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-η-amyl ketone, methyl isoamyl ketone, 2-heptanone; ethylene glycolol, diethylene glycolol, propylene glycolol Polyhydric alcohols such as dipropylene glycol and derivatives thereof; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate; Monoesters such as monomethyl ether, monoethylenoatenore, monopropinoreatenore, monobutinoleetenole, etc. Derivatives of polyhydric alcohols such as compounds having an ether bond such as nophenyl ether; cyclic ethers such as dioxane; methyl lactate, ethyl lactate (EU, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, Esters such as ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; anisole, Ethinolevenoreatenore, crezinoremethinoleatenore, diphenenoleatenore, dibenzenoleatenore, phenetenoreno, butinorefuenoreatenore, ethinorebenzene, jetinolebenzen, amylbenzene, isopropylene benzene Examples thereof include aromatic organic solvents such as cymene and mesitylene.

 These organic solvents may be used alone or as a mixed solvent of two or more. Of these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and ethyl lactate (EU are preferred.

 A mixed solvent in which PGMEA and a polar solvent are mixed is preferable. The mixing 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. Preferably within 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. When PGM E is blended as a polar solvent, the mass ratio of PGMEA: PGME is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2, more preferably 3: 7 to 7: Three.

 In addition, as the component (S), a mixed solvent of at least one selected from the medium strengths of PGMEA and EL and a γ-bubble outlet is also preferable. In this case, the mixing ratio of the former and the latter is preferably 70: 30-95: 5.

 The amount of component (S) used is not particularly limited, but it is a concentration that can be applied to a substrate and the like, and is appropriately set according to the coating film thickness. In general, the solid content concentration of the resist composition is 2 -20% by mass, preferably 5 to 15% by mass.

<Resist pattern formation method>

 The positive resist composition includes a step of forming a resist film on a substrate using the positive resist composition, a step of exposing the resist film, and a step of developing the resist film to form a resist pattern. It can be used for the resist pattern formation method containing.

The resist pattern forming method can be performed, for example, as follows. That is, first, the positive resist composition is applied onto a substrate such as a silicon wafer by using a spinner or the like, and optionally a pre-beta is applied to form a resist film. The formed resist film is exposed to an exposure apparatus such as an ArF exposure apparatus, an electron beam drawing apparatus, or an EUV exposure apparatus. Is selectively exposed by exposure through a mask pattern or drawing by direct irradiation of an electron beam not through a mask pattern, and then 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 positive resist composition to be used.

 The exposure light source is not particularly limited. ArF excimer laser, KrF excimer laser, F

 2 Can be performed using radiation such as excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), electron beam, X-ray, soft X-ray. In particular, the positive resist composition is effective for ArF excimer laser, electron beam or EUV, particularly ArF excimer laser or electron beam.

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

[0104] <Dissolution inhibitor>

 The compound (A1) can also be suitably used as a dissolution inhibitor for positive resist compositions. By using the dissolution inhibitor composed of the compound (A1), the alkali solubility of the resist film (before exposure) obtained using the positive resist composition containing the dissolution inhibitor is suppressed. Therefore, when the resist film is selectively exposed, a difference in alkali solubility (dissolution contrast) between the exposed portion and the unexposed portion is increased, and a resist pattern with good resolution and shape can be formed. .

 The dissolution inhibitor can be used by being added to a two-component chemically amplified resist composition containing a resin component having an acid dissociable dissolution inhibiting group and an acid generator component. It can also be used as a chemically amplified resist composition of V, or a three-component system, using a resin component, an acid generator component, and a dissolution inhibitor.

 Example 1

[0105] Examples of the present invention will be described below, but the scope of the present invention is not limited to these examples. Synthesis Example 1 (Synthesis of Compound (1))

 500 g of acetone was added to 30 g of methylenebissalicylaldehyde (1,) (Honshu Chemical Co., Ltd.) and dissolved. 48.6 g of potassium carbonate (K 2 CO 3) was added thereto and stirred for 10 minutes at room temperature.

 twenty three

 Stir. Thereafter, 45.72 g of tert butyl bromoacetate (2 ′) was added, and the mixture was reacted at room temperature for 12 hours.

 After completion of the reaction, the mixture was extracted with water / ethyl acetate (mass ratio 1: 1), and the ethyl acetate phase was concentrated under reduced pressure to obtain 53.5 g of the desired compound (3 ′).

 [Chemical 25]

[0107] Next, 2, 5 Dimethino Leunore 15.14 g (4,), Methanol (CH OH) 50 g, 35 quality

 Three

 12 g of compound (3 ′) was added to 10 g of a mixed solution of 10% by weight aqueous hydrochloric acid (HClaq.) And reacted at 60 ° C. for 3 days.

 After completion of the reaction, the temperature was returned to room temperature, and then an aqueous sodium hydroxide solution was added and stirred for 10 hours. Then, the reaction solution is transferred to a separatory funnel, washed with water / jetyl ether to remove the raw material, then the aqueous layer is extracted, neutralized with an aqueous hydrochloric acid solution (confirm neutrality with pH test paper), and precipitated. I got a thing. The precipitate was filtered to obtain crude crystals. The crude crystals were dissolved in tetrahydrofuran (THF) and reprecipitated with heptane. This was then filtered to obtain crude crystals. This crude crystal was dissolved in THF, and concentrated and dried to obtain 15.3 g of the desired compound (1).

[0108] [Chemical 26]

[0109] The compound (1) was analyzed by ifi—NMI ^ IR. The results are shown below.

¹ H—NMR data (deuterated dimethyl sulfoxide (DMSO—d6), 400 MHz, internal standard: tetramethylenosilane): δ (ppm) = 12.68 brs 2H H ^a , 8.94 brs 4H H ^b , 6. 82-6.27 m 14H ^{H c, 5.85 s 2H H d} , 4.47 s 4H H e, 3.32 s 2H H f, 2.09-1.76

brs 24H H ^g .

IR data: 3382cm ¹ , 2925cm ¹ , 1728cm ¹ , 1495cm ¹ , 1463cm ¹ , 141 lcm ¹ , 1285cm ¹ , 1227cm ¹ , 1195cm ¹ , 1119cm ¹ , 1075cm

 From this result, it was confirmed that the compound (1) had the structure shown below.

[0110] [Chemical 27]

[0111] Synthesis Example 2 (Synthesis of Compound (5))

 4 g of compound (1) is dissolved in 20 g of tetrahydrofuran (THF) and 1.52 g of Et N is added.

Stir for 10 minutes and add 2.79 g bromoacetic acid-2 methyl-2 adamantyl to it, Stir at room temperature for 10 hours. After completion of the reaction, the mixture was filtered, water / ethyl acetate (mass ratio 1: 1) was added to the obtained filtrate, extraction was performed, and the separated ethyl acetate phase was concentrated under reduced pressure to obtain the target compound (5). 3. 2g was obtained.

 [Chemical 28]

[0113] Compound (5) was analyzed by 1 H-NMR and IR.

¹ H—NMR (deuterated dimethyl sulfoxide (DMSO—d6), 400 MHz, internal standard: tetramethylenosilane): δ (ppm) = 8. 80 brs 4H H ^a , 6. 23— 6. 94 m 14H H ^b , 5. ^{84 s 2H H c, 4. 68} s 4H H d, 4. 68 s 4H H e, 3. 58 s 2H H f, 2. 19 s 4H H g, 1. 39- 2. 15 m 54H H h

IR: 3417cm— ¹ , 2920cm— ¹ , 2863cm— ¹ , 1750cm— ¹ , 1728cm— ¹ , 1495cm— ¹ , 1,292cm— ¹ , 1,278cm

 From the results shown above, it was confirmed that the compound (5) had a structure shown below. In the following structure, g represents a hydrogen atom (2 X 2) bonded to a carbon atom adjacent to the carbon atom to which the oxygen atom is directly bonded in the 2-methyl-2-adamantyl group, and h is This represents a hydrogen atom other than g in the 2-methyl-2-adamantyl group and a hydrogen atom in the methyl group bonded to the benzene ring.

[0114] [Chemical 29]

[0115] Example 1 (Synthesis of Compound (6))

 5 g of the low molecular compound (5) was dissolved in 40 g of tetrahydrofuran (THF), 0.78 g of sodium hydride was added and stirred for 10 minutes, 2.52 g of odomethane was added thereto, and the mixture was stirred at room temperature for 10 hours. After completion of the reaction, extraction with water / ethyl acetate was performed, and the separated ethyl acetate phase was concentrated under reduced pressure to obtain 4. lg of the desired compound (6).

 [0116] [Chemical 30]

 (S) (6)

[0117] Compound (6) was analyzed by 1 H-NMR and IR.

¹ H—NMR (Heavy Dimethyl Sulfoxide (DMSO—d6), 400 MHz, Internal Standard: Tetramethylolesilane): δ (ppm) = 6.34-6.86 m 14H H ^a , 5.85— 5.96 m 2H H ^b , 4.68 s 4H H ^c , 4.65 s 4H H ^d , 3.70 s 12H H ^e , 3.51— 3.59 m 2H H ^F , 1. 41-2. 27 m H ^G , H ^H , H ' ₀

IR: 2922 cm ¹ , 2861 cm ¹ , 1776 cm ¹ , 1748 cm ¹ , 1505 cm ¹ , 1199 cm From the above results, it was confirmed that the compound (6) had a structure shown below.

[0118] [Chemical 31]

Example 2 (Electron beam exposure)

 Each component was mixed and dissolved in the composition and blending amount shown in Table 1 to prepare a positive type and composition solution.

 Here, the unit of the amount shown in [] in Table 1 is part by mass.

 The abbreviations in Table 1 have the following meanings.

 • TPS—PFBS: Triphenyl-amine 1: Tri-n-octylamine.

 .PGMEA: Propylene glycol monomethyl ether acetate

 • EL: Lactic acid ethyl.

[0120] [Table 1]

[0121] The following evaluation was performed using the obtained positive resist composition solution. Figure 1 shows the results.

 A positive resist composition solution is uniformly applied on an 8-inch silicon substrate that has been subjected to hexamethyldisilazane treatment (90 ° C, 36s) using a spinner, and is baked at 110 ° C for 90 seconds. (PAB) was performed to form a resist film (film thickness 150 nm).

Using the electron beam lithography machine HL-800D (VSB) (manufactured by Hitachi), the resist film is drawn at an accelerating voltage of 70 kV (large area exposure (1 m square)), and 90 ° C at 90 ° C. The second And then developed for 60 seconds using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) (23 ° C.).

At that time, changes in resist film thickness (A) due to changes in electron beam (EB) exposure (electron beam exposure, C / cm ² ) were measured using a dissolution rate analyzer RDA-808RB (manufactured by LithoTech Japan). A sensitivity curve was created (Fig. 1).

 From the sensitivity curve of electron beam exposure in Fig. 1, it was confirmed that the film had a good contrast.

Industrial applicability

 The present invention provides a compound that can be used as a resist composition, a positive resist composition containing the compound, and a resist pattern forming method using the positive resist composition. Therefore, the present invention is extremely useful industrially.

Claims

Claims A compound represented by the following general formula (A-1). [In the formula (A-1), R ′ is a hydrogen atom or an acid dissociable, dissolution inhibiting group, and a plurality of R ′ may be the same or different from each other, Some are acid-releasing dissolution inhibiting groups; R ″ is an alkyl group having 1 to 10 carbon atoms; R ^{U to} R ¹⁷ are each independently an alkyl group having 1 to 10 carbon atoms; A hydrocarbon group which may contain a hetero atom in the structure; g and j are each independently an integer of 1 or more, k and q are integers of 0 or more, and g + j + k + q is 5 or less; a is an integer of 1 to 3; b is an integer of 1 or more, 1 and m are each independently an integer of 0 or more, and b + 1 + m is 4 or less C is an integer of 1 or more, n and o are each independently an integer of 0 or more, and c + n + o is 4 or less; A is represented by the following general formula (la) Represented by the following general formula (lb) Or an aliphatic cyclic group.] [Chemical 2]

 ί I a) (, ϊ b) [In the formula (la), R ¹⁸ and R ¹⁹ are each independently an alkyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms, and may contain a hetero atom in the structure thereof; r, y , Z are each independently an integer of 0 or more, and r + y + z is 4 or less. ] [2] The compound according to claim 1, which is represented by the following general formula (A-2).  [Chemical 3]

 (A ~ 2} [In the formula (A-2), R ′ is a hydrogen atom or an acid dissociable, dissolution inhibiting group, and a plurality of R ′ may be the same or different from each other. At least some of them are acid-dissolving dissolution inhibiting groups; R ″ is an alkyl group having 1 to 10 carbon atoms; R ^{U to} R ¹² are each independently an alkyl group having 1 to 10 carbon atoms; A group or an aromatic hydrocarbon group that may contain heteroatoms in its structure; a is an integer from 1 to 3; b ′ is an integer from 1 to 4; c ′ is ; Is an integer of 4 to 4; A is a group represented by the general formula (la), a group represented by the general formula (lb), or an aliphatic cyclic group. ]  A positive resist composition comprising a base component (A) whose alkali solubility is increased by the action of an acid, and an acid generator component (B) that generates an acid upon irradiation with radiation, the base component ( A positive resist composition in which A) contains a compound (A1) represented by the following general formula (A-1). [Chemical 4]

 (A-I) [In the formula (A-1), R ′ is a hydrogen atom or an acid dissociable, dissolution inhibiting group, and a plurality of R ′ may be the same or different from each other. At least some of them are acid-dissolvable dissolution inhibiting groups; R ″ is an alkyl group having 1 to 10 carbon atoms; R ^{U to} R ¹⁷ are each independently an alkyl group having 1 to 10 carbon atoms; A group or an aromatic hydrocarbon group which may contain a hetero atom in the structure; g and j are each independently an integer of 1 or more, k and q are integers of 0 or more, and g + j + k + q is 5 or less; a is an integer of 1 to 3; b is an integer of 1 or more, 1 and m are each independently an integer of 0 or more, and b + 1 + m is 4 or less; c is an integer of 1 or more, n and o are each independently an integer of 0 or more, and c + n + o is 4 or less; A is a group represented by the following general formula (la), a group represented by the following general formula (lb), or an aliphatic cyclic group. ] [Chemical 5]

[In the formula (la), R ^1Q and R ¹⁹ are each independently an alkyl group or an aromatic hydrocarbon group having 1 to 10 carbon atoms, and may contain a hetero atom in the structure thereof; r, y , Z are each independently an integer of 0 or more, and r + y + z is 4 or less. ]  4. The positive resist composition according to claim 3, wherein the compound (A1) is a compound represented by the following general formula (A-2). [Chemical 6]

[In the formula (A-2), R ′ is a hydrogen atom or an acid dissociable, dissolution inhibiting group, and a plurality of R ′ may be the same or different from each other. At least some of them are acid-dissolving dissolution inhibiting groups; R ″ is an alkyl group having 1 to 10 carbon atoms; R ^{U to} R ¹² are each independently an alkyl group having 1 to 10 carbon atoms; A group or an aromatic hydrocarbon group that may contain heteroatoms in its structure; a is an integer of 1 to 3; b ′ is an integer of !! to 4; c ′ is; An integer of 4; A is a group represented by the general formula (la), a group represented by the general formula (lb), or an aliphatic cyclic group. 5. The positive resist composition according to claim 3, further comprising a nitrogen-containing organic compound (D). [6] A step of forming a resist film on a substrate using the positive resist composition according to claim 3, a step of exposing the resist film, and a step of developing the resist film to form a resist pattern A resist pattern forming method.