JP5564883B2 - Dissolution inhibitor, negative radiation sensitive composition, and resist pattern forming method - Google Patents

Description

  The present invention relates to a dissolution inhibitor represented by a specific chemical structural formula useful as an acid-amplified non-polymer resist material, a negative radiation-sensitive composition containing the same, and a resist pattern forming method using the composition About.

Conventional general resist materials are polymer materials capable of forming an amorphous thin film. For example, a resist thin film prepared by applying a solution of a polymer resist material such as polymethyl methacrylate, polyhydroxystyrene having an acid dissociable reactive group or polyalkyl methacrylate on a substrate, ultraviolet rays, far ultraviolet rays, electron beams, A line pattern of about 45 to 100 nm is formed by irradiating extreme ultraviolet rays (EUV), X-rays or the like.
However, since the polymer resist has a large molecular weight of about 10,000 to 100,000 and a wide molecular weight distribution, the lithography using the polymer resist causes roughness on the surface of the fine pattern, making it difficult to control the pattern dimensions. , Yield decreases. Therefore, there is a limit to miniaturization in conventional lithography using a polymer resist material. In order to produce a finer pattern, there are disclosed alkali-developing negative radiation-sensitive compositions (see Patent Documents 1 to 3 and Non-Patent Document 1) using various low molecular weight resist materials as main components. .
However, the negative radiation-sensitive composition currently disclosed has low sensitivity, and improvement has been desired.

JP 2005-326838 A JP 2008-145539 A JP 2009-173623 A

T.A. Nakayama, M .; Nomura, K .; Haga, M .; Ueda: Bull. Chem. Soc. Jpn. 71, 2979 (1998)

  An object of the present invention is to provide a dissolution inhibitor represented by a specific chemical structural formula that improves the sensitivity of a negative radiation-sensitive composition, a negative radiation-sensitive composition containing the same, and resist pattern formation using the composition Is to provide a method.

（１）
（式（１）中、Ｒ^１は、独立して、炭素数３〜１２の直鎖状もしくは分岐状のアルキル基、炭素数３〜１２のシクロアルキル基であり、ｐは１〜５の整数である。）
２． 前記式（１）で示される溶解抑止剤、レジスト基材（Ｒ）および溶媒を含み、固形成分１〜８０重量％および溶媒２０〜９９重量％からなる感放射線性組成物であって、前記溶解抑止剤が固形成分全重量の１０〜５０重量％である感放射線性組成物。
３． さらに、可視光線、紫外線、エキシマレーザー、電子線、極端紫外線（ＥＵＶ）、Ｘ線、およびイオンビームからなる群から選ばれるいずれかの放射線の照射により直接的又は間接的に酸を発生する酸発生剤（Ｃ）を含む第２項記載の感放射線性組成物。
４． さらに、酸架橋剤（Ｇ）を含む第２項記載の感放射線性組成物。
５． さらに、酸拡散制御剤（Ｅ）を含む第２項記載の感放射線性組成物。
６． 第２項〜第５項のいずれかに記載の感放射線性組成物を用いて、基板上にレジスト膜を形成する工程、該レジスト膜を露光する工程、および該レジスト膜を現像してレジストパターンを形成する工程を含むレジストパターン形成方法。 As a result of intensive studies to solve the above problems, the present inventors have found that a dissolution inhibitor having a specific structure improves the sensitivity of a negative radiation-sensitive composition and gives a good resist pattern shape. The present invention has been reached.
That is, the present invention is as follows.
1. A dissolution inhibitor represented by the following formula (1).

(1)
(In formula (1), R ¹ is independently a linear or branched alkyl group having 3 to 12 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms, and p is an integer of 1 to 5) .)
2. A radiation-sensitive composition comprising a dissolution inhibitor represented by the formula (1), a resist base material (R) and a solvent, comprising 1 to 80% by weight of a solid component and 20 to 99% by weight of a solvent, wherein the dissolution A radiation-sensitive composition in which the inhibitor is 10 to 50% by weight based on the total weight of the solid components.
3. Furthermore, acid generation that directly or indirectly generates an acid upon irradiation with radiation selected from the group consisting of visible light, ultraviolet light, excimer laser, electron beam, extreme ultraviolet light (EUV), X-ray, and ion beam. The radiation sensitive composition of Claim 2 containing an agent (C).
4). The radiation-sensitive composition according to item 2, further comprising an acid crosslinking agent (G).
5. The radiation-sensitive composition according to item 2, further comprising an acid diffusion controller (E).
6). A step of forming a resist film on a substrate, a step of exposing the resist film using the radiation-sensitive composition according to any one of Items 2 to 5, and developing the resist film to develop a resist pattern A resist pattern forming method including a step of forming a film.

  According to the present invention, there are provided a dissolution inhibitor represented by a specific chemical structural formula for improving the sensitivity of a negative radiation sensitive composition, a negative radiation sensitive composition containing the dissolution inhibitor, and a resist pattern forming method using the composition. Can be provided.

Hereinafter, the present invention will be described in detail.
[Dissolution inhibitor]
The present invention relates to a dissolution inhibitor useful for improving the sensitivity of a negative radiation-sensitive composition. The dissolution inhibitor is a component having an effect of appropriately reducing the dissolution rate during development by controlling the solubility when the resist substrate is too soluble in a developer such as alkali. As such a dissolution inhibitor, those which do not chemically change in steps such as baking of resist film, irradiation with radiation, and development are preferable. Moreover, the higher the amorphousness of the dissolution inhibitor itself, the smaller the line edge roughness of the resist pattern.
The dissolution inhibitor of the present invention is a dissolution inhibitor represented by the following formula (1).

（１）

(1)

(In formula (1), R ¹ is independently a linear or branched alkyl group having 3 to 12 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms, and p is an integer of 1 to 5) .)

（２）
（式（２）中、Ｒ^１は前記と同様である。） The dissolution inhibitor represented by the above formula (1) is preferably the following dissolution inhibitor.

(2)
(In formula (2), R ¹ is the same as described above.)

The dissolution inhibitor of the present invention is a low molecular weight compound that has high heat resistance and is amorphous so that it has excellent film-forming properties, does not have sublimation properties, is excellent in alkaline developer dissolution inhibition, etching resistance, etc. In particular, it is suitably used as a dissolution inhibitor for resist materials.
Also, in terms of production, it can be produced in high yield by dehydrating condensation reaction with non-metallic catalysts such as hydrochloric acid using aromatic aldehydes having a specific structure and industrially produced resorcinol as raw materials. It is also extremely superior.

  In the present invention, among the dissolution inhibitors, a dissolution inhibitor represented by the following formula (3) is more preferable.

（３）
（式（３）中、Ｒ^１は前記と同様である。）

(3)
(In Formula (3), R ¹ is the same as described above.)

  In the present invention, among the dissolution inhibitors, a dissolution inhibitor selected from the compound group represented by the following formula (4) and the following formula (5) is particularly preferable.

  The molecular weight of the dissolution inhibitor represented by the above formula (1) is 1288 to 1736, preferably 1288 to 1550, more preferably 1288 to 1400. Within the above range, dissolution inhibiting performance can be imparted while maintaining the film forming properties required for the resist material.

  The dissolution inhibitor in the present invention can take a cis form and a trans form, but may have any structure or mixture. When used as a dissolution inhibitor for a negative radiation-sensitive composition, it is preferable to have only a cis- or trans-structure because the uniformity of the components in the resist film is high. A method for obtaining a dissolution inhibitor having only a cis- or trans-structure is performed by a known method such as separation by column chromatography or preparative liquid chromatography or optimization of reaction solvent and reaction temperature during production. be able to.

  The dissolution inhibitor represented by the above formula (1) is obtained by a condensation reaction with at least one selected from the group consisting of the aromatic carbonyl compound (A1) and resorcinol.

  The aromatic carbonyl compound (A1) is a cyclohexylbenzaldehyde having a linear or branched alkyl group having 3 to 12 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms, such as propylcyclohexylbenzaldehyde and butylcyclohexylbenzaldehyde. , Pentyl cyclohexyl benzaldehyde, hexyl cyclohexyl benzaldehyde, heptyl cyclohexyl benzaldehyde, octyl cyclohexyl benzaldehyde, decyl cyclohexyl benzaldehyde, dodecyl cyclohexyl benzaldehyde, dipropyl cyclohexyl benzaldehyde, dibutyl cyclohexyl benzaldehyde, dipentyl cyclohexyl benzaldehyde, propentyl cyclohexyl benzaldehyde Examples thereof include cyclohexyl benzaldehyde, cyclobutyl cyclohexyl benzaldehyde, cyclopentyl cyclohexyl benzaldehyde, cyclohexyl cyclohexyl benzaldehyde, cycloheptyl cyclohexyl benzaldehyde, cyclooctyl cyclohexyl benzaldehyde, cyclodecyl cyclohexyl benzaldehyde and cyclododecyl cyclohexyl benzaldehyde, and propyl cyclohexyl aldehyde. Cyclohexylbenzaldehyde and hexylcyclohexylbenzaldehyde are preferred, and propylcyclohexylbenzaldehyde, butylcyclohexylbenzaldehyde and pentylcyclohexylbenzaldehyde are preferred. Ri Preferably, propylcyclohexyl benzaldehyde is particularly preferable. The aromatic carbonyl compound (A1) may be used alone or in combination of two or more.

  The dissolution inhibitor represented by the above formula (1) can be produced by a known method. For example, in an organic solvent such as methanol and ethanol, 0.1 to 10 mol of resorcinol is used per 1 mol of the aromatic carbonyl compound (A1), and an acid catalyst (hydrochloric acid, sulfuric acid, paratoluenesulfonic acid, etc.) is used. It is obtained by reacting at 60 to 150 ° C. for about 0.5 to 20 hours, filtering, washing with an alcohol such as methanol, washing with water, filtering and separating, and drying. Instead of the acid catalyst, a basic catalyst (such as sodium hydroxide, barium hydroxide or 1,8-diazabicyclo [5.4.0] undecene-7) may be used and reacted in the same manner. Furthermore, the cyclic compound represented by the above formula (1) can also be produced by converting the aromatic carbonyl compound (A1) into a dihalide with hydrogen halide or halogen gas, and reacting the isolated dihalide with resorcinol. .

  More preferably, two or more aromatic carbonyl compounds (A1) are used. By using two or more aromatic carbonyl compounds (A1), the solubility of the resulting cyclic compound in a semiconductor safety solvent is improved.

  In order to reduce the residual metal amount of the dissolution inhibitor of the present invention, purification may be performed as necessary. In addition, when the acid catalyst remains, generally, the storage stability of the negative radiation sensitive composition is decreased, or when the basic catalyst remains, generally the sensitivity of the negative radiation sensitive composition is decreased. Purification for the purpose may be performed. Purification can be performed by a known method as long as the cyclic compound is not denatured, and is not particularly limited. For example, a method of washing with water, a method of washing with an acidic aqueous solution, a method of washing with a basic aqueous solution, or an ion exchange resin. The method of processing, the method of processing by silica gel column chromatography, etc. are mentioned. These purification methods are more preferably performed in combination of two or more. Acidic aqueous solution, basic aqueous solution, ion exchange resin, and silica gel column chromatography are optimal depending on the metal to be removed, the amount and type of acidic compound and / or basic compound, the type of dissolution inhibitor to be purified, etc. Can be selected as appropriate. For example, as acidic aqueous solution, hydrochloric acid, nitric acid, acetic acid aqueous solution having a concentration of 0.01 to 10 mol / L, aqueous ammonia solution having a concentration of 0.01 to 10 mol / L as basic aqueous solution, cation exchange resin as ion exchange resin, For example, Amberlyst 15J-HG Dry made by Organo can be mentioned. You may dry after refinement | purification. Drying can be performed by a known method, and is not particularly limited, and examples thereof include a vacuum drying method and a hot air drying method under conditions where the dissolution inhibitor is not denatured.

  The dissolution inhibitor represented by the above formula (1) can form an amorphous film by spin coating. Further, it can be applied to a general semiconductor manufacturing process.

  The dissolution inhibitor represented by the above formula (1) improves the sensitivity of a negative radiation sensitive composition that is hardly soluble in an alkali developer by irradiation with KrF excimer laser, extreme ultraviolet light, electron beam or X-ray. Therefore, it is useful as a dissolution inhibitor. The resist pattern thus obtained has a very low LER. The dissolution inhibitor is a cyclic compound that forms an amorphous film with a low molecular weight, and the condensation reaction between the dissolution inhibitors is induced by irradiation with KrF excimer laser, extreme ultraviolet light, electron beam, or X-ray. This is considered to be further insoluble.

  The dissolution rate of the amorphous film of the dissolution inhibitor of the present invention in a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution at 23 ° C is preferably 5 Å / sec or less, more preferably 0.05 to 5 Å / sec, More preferably, it is 0.0005-5 g / sec. If it is 5 kg / sec or less, it is insoluble in an alkali developer and can be applied as a dissolution inhibitor. In addition, when the dissolution rate is 0.0005 kg / sec or more, the resolution may be improved. This is presumed to be because the micro surface portion of the cyclic compound is dissolved and LER is reduced. There is also an effect of reducing defects.

The glass transition temperature of the dissolution inhibitor of the present invention is preferably 100 ° C. or higher, more preferably 120 ° C. or higher, still more preferably 140 ° C. or higher, and particularly preferably 150 ° C. or higher. When the glass transition temperature is within the above range, the semiconductor lithography process has heat resistance capable of maintaining the pattern shape and can provide performance such as high resolution.
The calorific value of crystallization determined by differential scanning calorimetry of the glass transition temperature of the dissolution inhibitor of the present invention is preferably less than 20 J / g. Further, (crystallization temperature) − (glass transition temperature) is preferably 70 ° C. or higher, more preferably 80 ° C. or higher, further preferably 100 ° C. or higher, and particularly preferably 130 ° C. or higher. When the crystallization heat generation amount is less than 20 J / g, or (crystallization temperature) − (glass transition temperature) is within the above range, an amorphous film can be easily formed by spin-coating the radiation-sensitive composition, and The film formability required for the resist can be maintained for a long time, and the resolution can be improved.

  In the present invention, the crystallization calorific value, crystallization temperature and glass transition temperature can be determined by measurement and differential scanning calorimetry as follows using DSC / TA-50WS manufactured by Shimadzu Corporation. About 10 mg of a sample is put in an aluminum non-sealed container and heated to a melting point or higher at a temperature rising rate of 20 ° C./min in a nitrogen gas stream (50 ml / min). After the rapid cooling, the temperature is again raised to the melting point or higher at a temperature rising rate of 20 ° C./min in a nitrogen gas stream (30 ml / min). Further, after rapid cooling, the temperature is increased again to 400 ° C. at a rate of temperature increase of 20 ° C./min in a nitrogen gas stream (30 ml / min). The temperature at the midpoint where the discontinuity appears in the baseline (where the specific heat has changed to half) is the glass transition temperature (Tg), and the temperature of the exothermic peak that appears thereafter is the crystallization temperature. The calorific value is obtained from the area of the region surrounded by the exothermic peak and the baseline, and is defined as the crystallization calorific value.

  The dissolution inhibitor of the present invention preferably has a low sublimation property under normal pressure at 100 ° C or lower, preferably 120 ° C or lower, more preferably 130 ° C or lower, further preferably 140 ° C or lower, particularly preferably 150 ° C or lower. . The low sublimation property means that, in thermogravimetric analysis, the weight loss when held at a predetermined temperature for 10 minutes is 10%, preferably 5%, more preferably 3%, still more preferably 1%, particularly preferably 0.1. % Or less is preferable. Since the sublimation property is low, it is possible to prevent exposure apparatus from being contaminated by outgas during exposure. Moreover, a favorable pattern shape can be given with low LER.

  The dissolution inhibitor of the present invention preferably satisfies F <3.0 (F represents the total number of atoms / (total number of carbon atoms−total number of oxygen atoms)), and more preferably satisfies F <2.5. By satisfying the above conditions, the dry etching resistance is excellent.

  The dissolution inhibitor of the present invention includes propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone (CHN), cyclopentanone (CPN), 2-heptanone, anisole, butyl acetate, ethyl propionate, And a solvent selected from ethyl lactate and having the highest solubility for the cyclic compound at 23 ° C., preferably 1% by weight or more, more preferably 5% by weight or more, and further preferably 10% by weight or more, Particularly preferably, it is dissolved in a solvent selected from PGMEA, PGME, and CHN and having the highest solubility for the cyclic compound at 23 ° C. by 20% by weight or more. By satisfying the above conditions, the semiconductor manufacturing process can be used in actual production.

  A non-acid dissociable functional group may be introduced into at least one phenolic hydroxyl group of the dissolution inhibitor as long as the effects of the present invention are not impaired. The non-acid-dissociable functional group refers to a characteristic group that does not cleave in the presence of an acid and does not generate an alkali-soluble group. For example, C1-20 alkyl group, C3-20 cycloalkyl group, C6-20 aryl group, C1-20 alkoxyl group, cyano group, nitro group, hydroxyl group, Examples thereof include a cyclic group, a halogen, a carboxyl group, a C1-20 alkylsilane, and a functional group selected from the group consisting of these derivatives.

[Negative type radiation sensitive composition]
The present invention is a radiation-sensitive composition comprising a dissolution inhibitor represented by the above formula (1), a resist base material (R) and a solvent, and comprising 1 to 80% by weight of a solid component and 20 to 99% by weight of a solvent. In addition, the dissolution inhibitor is preferably 10 to 50% by weight of the total weight of the solid component.

  The radiation-sensitive composition of the present invention can form an amorphous film by spin coating. The dissolution rate of the amorphous film formed by spin-coating the radiation-sensitive composition of the present invention in a 2.38 mass% TMAH aqueous solution at 23 ° C is preferably 10 Å / sec or more, more preferably 10 to 10,000 Å / sec, 100 More preferably, it is -1000 kg / sec. It can melt | dissolve in an alkali developing solution as it is 10 tons / sec or more, and can be set as a resist. In addition, when the dissolution rate is 10000 kg / sec or less, the resolution may be improved. This is presumed to be due to the increase in the contrast of the interface between the unexposed portion dissolved in the alkali developer and the exposed portion not dissolved in the alkali developer due to the change in solubility of the cyclic compound before and after exposure. Further, there is an effect of reducing LER and reducing defects.

  Dissolution of a portion exposed to radiation such as KrF excimer laser, extreme ultraviolet light, electron beam or X-ray of an amorphous film formed by spin-coating the radiation-sensitive composition of the present invention in a 2.38 mass% TMAH aqueous solution at 23 ° C. The speed is preferably 5 K / sec or less, more preferably 0.05 to 5 K / sec, and still more preferably 0.0005 to 5 K / sec. If it is 5 Å / sec or less, it is insoluble in an alkali developer and can be used as a resist. In addition, when the dissolution rate is 0.0005 kg / sec or more, the resolution may be improved. This is presumed to be because the micro surface portion of the cyclic compound is dissolved and LER is reduced. There is also an effect of reducing defects.

The radiation-sensitive composition of the present invention is preferably 1 to 80% by weight of a solid component and 20 to 99% by weight of a solvent, more preferably 1 to 50% by weight of a solid component and 50 to 99% by weight of a solvent, still more preferably. The solid component is 2 to 40% by weight and the solvent is 60 to 98% by weight, and particularly preferably the solid component is 2 to 10% by weight and the solvent is 90 to 98% by weight.
The amount of the dissolution inhibitor represented by the formula (1) is the total weight of the solid components (dissolution inhibitor, resist base material (R), acid generator (C), acid crosslinking agent (G), acid diffusion controller (E ) And the total of solid components optionally used such as other components (F), the same applies hereinafter), preferably 10 to 50% by weight, more preferably 12.5 to 17. 5% by weight. When the blending ratio is above, high sensitivity is obtained and the line edge roughness is reduced.

  The negative radiation-sensitive composition of the present invention preferably contains one or more resist base materials (R). The amount of the resist base material (R) used is appropriately determined depending on the dissolution rate of the solid component in a 2.38% by mass TMAH aqueous solution at 23 ° C., and is preferably 50 to 90% by weight of the total weight of the solid component, more preferably. It is 65 to 80% by weight, more preferably 60 to 70% by weight. When the blending ratio is as described above, high resolution is obtained and the line edge roughness is reduced.

  As the resist base material (R), either a polymer resist base material (R1) or a non-polymer resist base material (R2) can be applied, but the non-polymer resist base material (R2) ( Hereinafter, the low molecular resist base material (also referred to as R2) is preferable because the line edge roughness of the resulting resist pattern is reduced.

  Examples of the polymer resist base material (R1) include phenol novolac resins, cresol novolac resins, hydroxystyrene resins, (meth) used in chemically amplified radiation-sensitive compositions for g-line, i-line, KrF, and ArF. It can be appropriately selected from those proposed for acrylic acid resins and the like.

  Examples of the low molecular resist base material (R2) include polynuclear polyphenols, cyclic polyphenols, polynuclears used in chemically amplified radiation-sensitive compositions for ArF, electron beams, extreme ultraviolet light (EUV), X-rays, and ion beams. It can be appropriately selected from those proposed for polycarboxylic acids, cyclic polycarboxylic acids and the like.

  As the low molecular weight resist base material (R2), cyclic polyphenol and cyclic polycarboxylic acid are preferable because they have high heat resistance sufficient for forming a resist pattern, and cyclic polyphenol is more preferable because of easy production.

  The low molecular resist base material (R2) is preferably at least one selected from the group consisting of compounds represented by the following formula (6-1).

（６−１）
（式（６−１）において、Ｒ^４は、は炭素数１〜２０のアルキル基、炭素数３〜２０のシクロアルキル基、炭素数６〜２０のアリール基、炭素数１〜２０のアルコキシ基、シアノ基、ニトロ基、複素環基、ハロゲン、カルボキシル基、炭素数１〜２０のアルキルシリル基、およびこれらの誘導体からなる群から選択される官能基であり、Ｘ_２は、ｍは１〜４の整数であり、水素又はハロゲン原子であり、ｍ_５は０〜３の整数であり、ｍ＋ｍ_５＝４であり、ｐ_２は０〜５の整数である。）

(6-1)
(In Formula (6-1), R ⁴ is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an alkoxy group having 1 to 20 carbon atoms. , a cyano group, a nitro group, a heterocyclic group, a halogen, a carboxyl group, functional group selected alkylsilyl group having 1 to 20 carbon atoms, and from the group consisting of derivatives, X _2, m is 1 4 is an integer of 4, hydrogen or a halogen atom, m ₅ is an integer of 0 to 3, m + m ₅ = 4, and p ₂ is an integer of 0 to _5. )

  The low molecular weight resist base material (R2) is more preferably at least one selected from the group consisting of compounds represented by the following formula (6-2).

（６−２）
（式（６−２）中、ｍ_３は２であり、ｍ_４は１であり、Ｒ^４、Ｘ_２、ｐ_２は前記と同様である。）

(6-2)
(In Formula (6-2), m ₃ is 2, m ₄ is 1, and R ⁴ , X ₂ , and p ₂ are the same as described above.)

  The low molecular resist base material (R2) is more preferably at least one selected from the group consisting of compounds represented by the following formula (6-3).

（６−３）
（式（６−３）中、Ｒ^４、ｐ_２は前記と同様である。）

(6-3)
(In formula (6-3), R ⁴ and p ₂ are the same as above.)

  The low molecular weight resist substrate (R2) is particularly preferably at least one selected from the group consisting of compounds represented by the following formula (6-4).

  The radiation-sensitive composition of the present invention can be directly or indirectly oxidized by irradiation with any radiation selected from visible light, ultraviolet light, excimer laser, electron beam, extreme ultraviolet light (EUV), X-ray, and ion beam. It is preferable to include one or more acid generators (C) that generate water. The amount of the acid generator used is preferably 0.001 to 50% by weight, more preferably 1 to 40% by weight, still more preferably 3 to 30% by weight, and particularly preferably 10 to 25% by weight based on the total weight of the solid components. By using within the above range, a pattern profile with high sensitivity and low edge roughness can be obtained. In the present invention, the acid generation method is not limited as long as an acid is generated in the system. If excimer laser is used instead of ultraviolet rays such as g-line and i-line, finer processing is possible, and if high-energy rays are used, electron beam, extreme ultraviolet rays, X-rays, ion beam, further fine processing Is possible.

（７−１）
（式（７−１）中、Ｒ^１３は、同一でも異なっていても良く、それぞれ独立に、水素原子、直鎖状、分枝状もしくは環状アルキル基、直鎖状、分枝状もしくは環状アルコキシ基、ヒドロキシル基またはハロゲン原子であり；Ｘ^-は、アルキル基、アリール基、ハロゲン置換アルキル基もしくはハロゲン置換アリール基を有するスルホン酸イオンまたはハロゲン化物イオンである。） The acid generator (C) is preferably at least one selected from the group consisting of compounds represented by the following formulas (7-1) to (7-8).

(7-1)
(In formula (7-1), R ¹³ may be the same or different and each independently represents a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group. group, a hydroxyl group or a halogen atom; X ^- is an alkyl group, an aryl group, a sulfonic acid ion or halide ion having a halogen-substituted alkyl group or halogen-substituted aryl group).

  The compound represented by the formula (7-1) includes triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, diphenyltolylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-. Octanesulfonate, diphenyl-4-methylphenylsulfonium trifluoromethanesulfonate, di-2,4,6-trimethylphenylsulfonium trifluoromethanesulfonate, diphenyl-4-t-butoxyphenylsulfonium trifluoromethanesulfonate, diphenyl-4-t-butoxyphenyl Sulfonium nonafluoro-n-butanesulfonate, diphenyl-4-hydroxyphenylsulfonium trifluoromethanes Phonate, bis (4-fluorophenyl) -4-hydroxyphenylsulfonium trifluoromethanesulfonate, diphenyl-4-hydroxyphenylsulfonium nonafluoro-n-butanesulfonate, bis (4-hydroxyphenyl) -phenylsulfonium trifluoromethanesulfonate, tri ( 4-methoxyphenyl) sulfonium trifluoromethanesulfonate, tri (4-fluorophenyl) sulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate, triphenylsulfoniumbenzenesulfonate, diphenyl-2,4,6-trimethylphenyl-p-toluene Sulfonate, diphenyl-2,4,6-trimethylphenylsulfonium-2-trifluoromethylben Zensulfonate, diphenyl-2,4,6-trimethylphenylsulfonium-4-trifluoromethylbenzenesulfonate, diphenyl-2,4,6-trimethylphenylsulfonium-2,4-difluorobenzenesulfonate, diphenyl-2,4,6 -Trimethylphenylsulfonium hexafluorobenzenesulfonate, diphenylnaphthylsulfonium trifluoromethanesulfonate, diphenyl-4-hydroxyphenylsulfonium-p-toluenesulfonate, triphenylsulfonium 10-camphorsulfonate, diphenyl-4-hydroxyphenylsulfonium 10-camphorsulfonate and cyclo (1,3-perfluoropropanedisulfone) at least selected from the group consisting of imidates It is preferable that the type.

（７−２）
（式（７−２）中、Ｒ^１４は、同一でも異なっていても良く、それぞれ独立に、水素原子、直鎖状、分枝状もしくは環状アルキル基、直鎖状、分枝状もしくは環状アルコキシ基、ヒドロキシル基またはハロゲン原子を表す。Ｘ^-は前記と同様である。）

(7-2)
(In formula (7-2), R ¹⁴ may be the same or different and each independently represents a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group. A group, a hydroxyl group or a halogen atom, X ⁻ is the same as defined above.)

  The compound represented by the formula (7-2) includes bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t -Butylphenyl) iodonium perfluoro-n-octanesulfonate, bis (4-t-butylphenyl) iodonium p-toluenesulfonate, bis (4-t-butylphenyl) iodoniumbenzenesulfonate, bis (4-t-butylphenyl) Iodonium-2-trifluoromethylbenzenesulfonate, bis (4-t-butylphenyl) iodonium-4-trifluoromethylbenzenesulfonate, bis (4-t-butylphenyl) iodonium-2,4-difluorobenzenesulfonate, bis ( 4-t Butylphenyl) iodonium hexafluorobenzenesulfonate, bis (4-t-butylphenyl) iodonium 10-camphorsulfonate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, Diphenyliodonium p-toluenesulfonate, diphenyliodoniumbenzenesulfonate, diphenyliodonium10-camphorsulfonate, diphenyliodonium-2-trifluoromethylbenzenesulfonate, diphenyliodonium-4-trifluoromethylbenzenesulfonate, diphenyliodonium-2,4-difluorobenzene Sulfonate, diphenyl Iodonium hexafluorobenzenesulfonate, di (4-trifluoromethylphenyl) iodonium trifluoromethanesulfonate, di (4-trifluoromethylphenyl) iodonium nonafluoro-n-butanesulfonate, di (4-trifluoromethylphenyl) iodonium per From fluoro-n-octanesulfonate, di (4-trifluoromethylphenyl) iodonium p-toluenesulfonate, di (4-trifluoromethylphenyl) iodoniumbenzenesulfonate and di (4-trifluoromethylphenyl) iodonium 10-camphorsulfonate Preferably, at least one selected from the group consisting of:

（７−３）
（式（７−３）Ｑはアルキレン基、アリーレン基またはアルコキシレン基であり、Ｒ^１５はアルキル基、アリール基、ハロゲン置換アルキル基またはハロゲン置換アリール基である。）

(7-3)
(Formula (7-3) Q is an alkylene group, an arylene group or an alkoxylene group, and R ¹⁵ is an alkyl group, an aryl group, a halogen-substituted alkyl group or a halogen-substituted aryl group.)

  The compound represented by the formula (7-3) includes N- (trifluoromethylsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) diphenylmaleimide, N- ( Trifluoromethylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy) naphthylimide, N- (10-camphorsulfonyloxy) Succinimide, N- (10-camphorsulfonyloxy) phthalimide, N- (10-camphorsulfonyloxy) diphenylmaleimide, N- (10-camphorsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2 , 3-Dicarboximide, N- 10-camphorsulfonyloxy) naphthylimide, N- (n-octanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (n-octanesulfonyloxy) Naphthylimide, N- (p-toluenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (p-toluenesulfonyloxy) naphthylimide, N- (2 -Trifluoromethylbenzenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (2-trifluoromethylbenzenesulfonyloxy) naphthylimide, N- (4 -Trifluoromethylbenzenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxy Imido, N- (4-trifluoromethylbenzenesulfonyloxy) naphthylimide, N- (perfluorobenzenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (Perfluorobenzenesulfonyloxy) naphthylimide, N- (1-naphthalenesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (1-naphthalenesulfonyloxy) Naphthylimide, N- (nonafluoro-n-butanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (nonafluoro-n-butanesulfonyloxy) naphthylimide, N- (perfluoro-n-octanesulfonyloxy) bicyclo [2.2.1] hept It is preferably at least one selected from 5-En 2,3-dicarboximide, and N- (perfluoro--n- C1-12alkyl oxy) group consisting naphthylimide.

（７−４）
（式（７−４）中、Ｒ^１６は、同一でも異なっていても良く、それぞれ独立に、任意に置換された直鎖、分枝もしくは環状アルキル基、任意に置換されたアリール基、任意に置換されたヘテロアリール基または任意に置換されたアラルキル基である。）

(7-4)
(In Formula (7-4), R ¹⁶ may be the same or different, and each independently represents an optionally substituted linear, branched or cyclic alkyl group, an optionally substituted aryl group, optionally A substituted heteroaryl group or an optionally substituted aralkyl group.)

  The compound represented by the formula (7-4) is diphenyl disulfone, di (4-methylphenyl) disulfone, dinaphthyl disulfone, di (4-tert-butylphenyl) disulfone, di (4-hydroxyphenyl) disulfone. , Di (3-hydroxynaphthyl) disulfone, di (4-fluorophenyl) disulfone, di (2-fluorophenyl) disulfone, and di (4-trifluoromethylphenyl) disulfone It is preferable.

（７−５）
（式（７−５）中、Ｒ^１７は、同一でも異なっていても良く、それぞれ独立に、任意に置換された直鎖、分枝もしくは環状アルキル基、任意に置換されたアリール基、任意に置換されたヘテロアリール基または任意に置換されたアラルキル基である。）

(7-5)
(In formula (7-5), R ¹⁷ may be the same or different, and each independently represents an optionally substituted linear, branched or cyclic alkyl group, an optionally substituted aryl group, optionally A substituted heteroaryl group or an optionally substituted aralkyl group.)

  The compound represented by the formula (7-5) is α- (methylsulfonyloxyimino) -phenylacetonitrile, α- (methylsulfonyloxyimino) -4-methoxyphenylacetonitrile, α- (trifluoromethylsulfonyloxyimino). -Phenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -4-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -4-methoxyphenylacetonitrile, α- (propylsulfonyloxyimino) -4-methylphenylacetonitrile And at least one selected from the group consisting of α- (methylsulfonyloxyimino) -4-bromophenylacetonitrile.

（７−６）
（式（７−６）中、Ｒ^１８は、同一でも異なっていても良く、それぞれ独立に、１以上の塩素原子および１以上の臭素原子を有するハロゲン化アルキル基である。ハロゲン化アルキル基の炭素原子数は１〜５が好ましい。）

(7-6)
(In the formula (7-6), R ^{18 s} may be the same or different, and are each independently a halogenated alkyl group having one or more chlorine atoms and one or more bromine atoms. The number of carbon atoms is preferably 1 to 5.)

（７−７）

(7-7)

（７−８）

(7-8)

In the formulas (7-7) and (7-8), R ¹⁹ and R ²⁰ are each independently an alkyl group having 1 to 3 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or cyclopentyl. Group, cycloalkyl group such as cyclohexyl group, alkoxyl group having 1 to 3 carbon atoms such as methoxy group, ethoxy group and propoxy group, or aryl group such as phenyl group, toluyl group and naphthyl group, preferably 6 carbon atoms -10 aryl groups. L ¹⁹ and L ²⁰ are each independently an organic group having a 1,2-naphthoquinonediazide group. Specific examples of the organic group having a 1,2-naphthoquinonediazide group include a 1,2-naphthoquinonediazide-4-sulfonyl group, a 1,2-naphthoquinonediazide-5-sulfonyl group, and a 1,2-naphthoquinonediazide- A 1,2-quinonediazidosulfonyl group such as a 6-sulfonyl group can be mentioned as a preferable one. In particular, 1,2-naphthoquinonediazido-4-sulfonyl group and 1,2-naphthoquinonediazide-5-sulfonyl group are preferable. p is an integer of 1 to 3, q is an integer of 0 to 4, and 1 ≦ p + q ≦ 5. J ¹⁹ is a single bond, a polymethylene group having 1 to 4 carbon atoms, a cycloalkylene group, a phenylene group, a group represented by the following formula (7-7-1), a carbonyl group, an ester group, an amide group or an ether group. , Y ¹⁹ is a hydrogen atom, an alkyl group or an aryl group, and X ²⁰ is independently a group represented by the following formula (7-8-1).

（７−７−１）

(7-7-1)

（７−８−１）
（式（７−８−１）中、Ｚ^２２はそれぞれ独立に、アルキル基、シクロアルキル基またはアリール基であり、Ｒ^２２はアルキル基、シクロアルキル基またはアルコキシル基であり、ｒは０〜３の整数である。）

(7-8-1)
(In formula (7-8-1), Z ²² each independently represents an alkyl group, a cycloalkyl group, or an aryl group, R ²² represents an alkyl group, a cycloalkyl group, or an alkoxyl group, and r is 0 to 3). Is an integer.)

  Other acid generators include bis (p-toluenesulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane, bis (tert-butylsulfonyl) diazomethane, bis (n-butylsulfonyl) diazomethane, bis (isobutylsulfonyl) ) Diazomethane, bis (isopropylsulfonyl) diazomethane, bis (n-propylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (isopropylsulfonyl) diazomethane, 1,3-bis (cyclohexylsulfonylazomethylsulfonyl) propane, 1, 4 -Bis (phenylsulfonylazomethylsulfonyl) butane, 1,6-bis (phenylsulfonylazomethylsulfonyl) hexane, 1,10-bis (cyclohexylsulfonyla) Bissulfonyldiazomethanes such as methylsulfonyl) decane, 2- (4-methoxyphenyl) -4,6- (bistrichloromethyl) -1,3,5-triazine, 2- (4-methoxynaphthyl) -4,6 Halogen-containing triazine derivatives such as-(bistrichloromethyl) -1,3,5-triazine, tris (2,3-dibromopropyl) -1,3,5-triazine, tris (2,3-dibromopropyl) isocyanurate Etc.

Among the acid generators, acid generators having an aromatic ring are preferable, and an acid generator represented by formula (7-1) or (7-2) is more preferable. An acid generator having a sulfonate ion having an aryl group or a halogen-substituted aryl group as X ^{− in the} formula (7-1) or (7-2) is more preferable, and an acid generator having a sulfonate ion having an aryl group Are particularly preferable, and diphenyltrimethylphenylsulfonium p-toluenesulfonate, triphenylsulfonium p-toluenesulfonate, triphenylsulfonium trifluoromethanesulfonate, and triphenylsulfonium nonafluoromethanesulfonate are particularly preferable. LER can be reduced by using the acid generator.
The acid generator (C) can be used alone or in combination of two or more.

  The negative radiation-sensitive composition of the present invention preferably contains one or more acid crosslinking agents (G). The acid crosslinking agent (G) is a compound that can crosslink the cyclic compound (A) in the molecule or between molecules in the presence of an acid generated from the acid generator (C). Examples of such an acid crosslinking agent (G) include compounds having one or more substituents (hereinafter referred to as “crosslinkable substituents”) having crosslinking reactivity with the cyclic compound (A). it can.

  Specific examples of such crosslinkable substituents include (i) hydroxyalkyl such as hydroxy (C1-C6 alkyl group), C1-C6 alkoxy (C1-C6 alkyl group), acetoxy (C1-C6 alkyl group) and the like. A group or a substituent derived therefrom; (ii) a carbonyl group such as formyl group, carboxy (C1-C6 alkyl group) or a substituent derived therefrom; (iii) a dimethylaminomethyl group, a diethylaminomethyl group, a di Nitrogen-containing substituents such as methylolaminomethyl group, diethylolaminomethyl group, morpholinomethyl group; (iv) glycidyl group-containing substituents such as glycidyl ether group, glycidyl ester group, glycidylamino group; (v) benzyloxy C1-C6 allyloxy (C1-C) such as methyl group, benzoyloxymethyl group 6 alkyl groups), substituents derived from aromatic groups such as C1-C6 aralkyloxy (C1-C6 alkyl groups); (vi) substituents containing polymerizable multiple bonds such as vinyl groups and isopropenyl groups. be able to. As the crosslinkable substituent of the acid crosslinking agent (G) of the present invention, a hydroxyalkyl group, an alkoxyalkyl group, and the like are preferable, and an alkoxymethyl group is particularly preferable.

  Examples of the acid crosslinking agent (G) having a crosslinkable substituent include (i) a methylol group-containing melamine compound, a methylol group-containing benzoguanamine compound, a methylol group-containing urea compound, a methylol group-containing glycoluril compound, and a methylol group-containing phenol compound. (Ii) alkoxyalkyl group-containing melamine compounds, alkoxyalkyl group-containing benzoguanamine compounds, alkoxyalkyl group-containing urea compounds, alkoxyalkyl group-containing glycoluril compounds, alkoxyalkyl group-containing phenol compounds, etc. Containing compound; (iii) carboxymethyl group-containing melamine compound, carboxymethyl group-containing benzoguanamine compound, carboxymethyl group-containing urea compound, carboxymethyl group-containing Carboxymethyl group-containing compounds such as recall uril compounds and carboxymethyl group-containing phenol compounds; (iv) bisphenol A epoxy compounds, bisphenol F epoxy compounds, bisphenol S epoxy compounds, novolak resin epoxy compounds, resole resin epoxy compounds And epoxy compounds such as poly (hydroxystyrene) -based epoxy compounds.

As the acid crosslinking agent (G), it is further possible to use a compound having a phenolic hydroxyl group and a compound and a resin imparted with a crosslinking property by introducing the crosslinking substituent into an acidic functional group in the alkali-soluble resin. it can. The introduction rate of the crosslinkable substituent in that case is usually 5 to 100 mol%, preferably 10 to 60 mol%, more preferably 10 to 60 mol%, based on the total acidic functional groups in the compound having a phenolic hydroxyl group and the alkali-soluble resin. Preferably, it is adjusted to 15 to 40 mol%. Within the above range, the cross-linking reaction occurs sufficiently, and a decrease in the remaining film ratio, a pattern swelling phenomenon, meandering, and the like can be avoided.
In the negative radiation-sensitive composition of the present invention, the acid crosslinking agent (G) is preferably an alkoxyalkylated urea compound or a resin thereof, or an alkoxyalkylated glycoluril compound or a resin thereof. Particularly preferred acid crosslinking agents (G) include compounds represented by the following formula (8) and alkoxymethylated melamine compounds (acid crosslinking agents (G1)).

（上記式（８）中、Ｒ^７はそれぞれ独立して、水素原子、アルキル基、またはアシル基を表し；Ｒ^８〜Ｒ^１１はそれぞれ独立して、水素原子、水酸基、アルキル基、またはアルコキシル基を示し；Ｘ^２は、単結合、メチレン基、または酸素原子を示す。）

(In the formula (8), R ⁷ each independently represents a hydrogen atom, an alkyl group, or an acyl group; R ^{8 to} R ¹¹ each independently represent a hydrogen atom, a hydroxyl group, an alkyl group, or an alkoxyl group. X ² represents a single bond, a methylene group, or an oxygen atom.)

In Formula (8), R ⁷ is preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an acyl group having 2 to 6 carbon atoms. The alkyl group having 1 to 6 carbon atoms is more preferably an alkyl group having 1 to 3 carbon atoms, and examples thereof include a methyl group, an ethyl group, and a propyl group. The acyl group having 2 to 6 carbon atoms is more preferably an acyl group having 2 to 4 carbon atoms, and examples thereof include an acetyl group and a propionyl group. R ^{8 to} R ¹¹ in Formula (8) are preferably a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, or an alkoxyl group having 1 to 6 carbon atoms. The alkyl group having 1 to 6 carbon atoms is preferably an alkyl group having 1 to 3 carbon atoms, and examples thereof include a methyl group, an ethyl group, and a propyl group. The alkoxy group having 1 to 6 carbon atoms is preferably an alkoxy group having 1 to 3 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, and a propoxy group. X ² represents a single bond, a methylene group, or an oxygen atom, and preferably a single bond or a methylene group. R ^{7 to} R ¹¹ and X ² each have a substituent such as an alkyl group such as a methyl group or an ethyl group, an alkoxy group such as a methoxy group or an ethoxy group, a hydroxyl group or a halogen atom in addition to the groups exemplified above. You may do it. The plurality of R ⁷ and R ^{8 to} R ¹¹ may be the same or different.

Specific examples of the compound represented by the formula (8-1) include the compounds shown below.

  Specific examples of the compound represented by the formula (8-2) include, for example, N, N, N, N-tetra (methoxymethyl) glycoluril, N, N, N, N-tetra (ethoxymethyl) glycoluril. N, N, N, N-tetra (n-propoxymethyl) glycoluril, N, N, N, N-tetra (isopropoxymethyl) glycoluril, N, N, N, N-tetra (n-butoxymethyl) ) Glycoluril, N, N, N, N-tetra (t-butoxymethyl) glycoluril, and the like. Among these, N, N, N, N-tetra (methoxymethyl) glycoluril is particularly preferable.

Specific examples of the compound represented by the formula (8-3) include the compounds shown below.

Specific examples of the alkoxymethylated melamine compound include N, N, N, N, N, N-hexa (methoxymethyl) melamine, N, N, N, N, N, N-hexa (ethoxymethyl) melamine N, N, N, N, N, N-hexa (n-propoxymethyl) melamine, N, N, N, N, N, N-hexa (isopropoxymethyl) melamine, N, N, N, N, Examples thereof include N, N-hexa (n-butoxymethyl) melamine, N, N, N, N, N, N-hexa (t-butoxymethyl) melamine and the like. Among these, N, N, N, N, N, N-hexa (methoxymethyl) melamine is particularly preferable.
The acid crosslinking agent (G1) is obtained by, for example, condensing a urea compound or a glycoluril compound, and formalin to introduce a methylol group, and then ether with lower alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, and butyl alcohol. Then, the reaction solution is cooled and the precipitated compound or its resin is recovered. The acid cross-linking agent (G1) can also be obtained as a commercial product such as CYMEL (trade name, manufactured by Mitsui Cyanamid) or Nicalac (manufactured by Sanwa Chemical Co., Ltd.).

  Further, as other particularly preferable acid crosslinking agent (G), the molecule has 1 to 6 benzene rings, and has at least two hydroxyalkyl groups and / or alkoxyalkyl groups in the molecule. And / or a phenol derivative in which an alkoxyalkyl group is bonded to any one of the benzene rings (acid crosslinking agent (G2)). Preferably, the molecular weight is 1500 or less, the molecule has 1 to 6 benzene rings, and the hydroxyalkyl group and / or alkoxyalkyl group has 2 or more in total, and the hydroxyalkyl group and / or alkoxyalkyl group is the benzene. A phenol derivative formed by bonding to any one or a plurality of benzene rings can be given.

  As a hydroxyalkyl group couple | bonded with a benzene ring, C1-C6 things, such as a hydroxymethyl group, 2-hydroxyethyl group, and 2-hydroxy-1-propyl group, are preferable. As an alkoxyalkyl group couple | bonded with a benzene ring, a C2-C6 thing is preferable. Specifically, methoxymethyl group, ethoxymethyl group, n-propoxymethyl group, isopropoxymethyl group, n-butoxymethyl group, isobutoxymethyl group, sec-butoxymethyl group, t-butoxymethyl group, 2-methoxyethyl And a 2-methoxy-1-propyl group are preferred.

Among these phenol derivatives, particularly preferable ones are listed below.

In the above formula, L ^{1 to} L ⁸ may be the same or different and each independently represents a hydroxymethyl group, a methoxymethyl group or an ethoxymethyl group. A phenol derivative having a hydroxymethyl group can be obtained by reacting a phenol compound not having a corresponding hydroxymethyl group (a compound in which L ^{1 to} L ⁸ are hydrogen atoms in the above formula) with formaldehyde in the presence of a base catalyst. it can. At this time, in order to prevent resinification or gelation, the reaction temperature is preferably 60 ° C. or lower. Specifically, they can be synthesized by the methods described in JP-A-6-282067, JP-A-7-64285 and the like.
A phenol derivative having an alkoxymethyl group can be obtained by reacting a corresponding phenol derivative having a hydroxymethyl group with an alcohol in the presence of an acid catalyst. At this time, in order to prevent resinification and gelation, the reaction temperature is preferably 100 ° C. or lower. Specifically, it can be synthesized by the method described in EP632003A1 and the like.

  A phenol derivative having a hydroxymethyl group and / or an alkoxymethyl group synthesized in this manner is preferable in terms of stability during storage, but a phenol derivative having an alkoxymethyl group is particularly preferable from the viewpoint of stability during storage. preferable. The acid crosslinking agent (G2) may be used alone or in combination of two or more.

Another particularly preferable acid crosslinking agent (G) is a compound having at least one α-hydroxyisopropyl group (acid crosslinking agent (G3)). The structure is not particularly limited as long as it has an α-hydroxyisopropyl group. In addition, the hydrogen atom of the hydroxyl group in the α-hydroxyisopropyl group is one or more acid dissociable groups (R—COO— group, R—SO ₂ — group, etc., R is a straight chain having 1 to 12 carbon atoms) A hydrocarbon group, a cyclic hydrocarbon group having 3 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, a 1-branched alkyl group having 3 to 12 carbon atoms, and an aromatic hydrocarbon group having 6 to 12 carbon atoms Which represents a substituent selected from the group consisting of: Examples of the compound having the α-hydroxyisopropyl group include one or two kinds such as a substituted or unsubstituted aromatic compound, diphenyl compound, naphthalene compound, and furan compound containing at least one α-hydroxyisopropyl group. The above is mentioned. Specifically, for example, a compound represented by the following general formula (9-1) (hereinafter referred to as “benzene compound (1)”), a compound represented by the following general formula (9-2) (hereinafter referred to as “benzene compound (1)”). , “Diphenyl compound (2)”), a compound represented by the following general formula (9-3) (hereinafter referred to as “naphthalene compound (3”)), and the following general formula (9-4). And the like (hereinafter referred to as “furan compound (4)”).

In the general formulas (9-1) to (9-4), each A ² independently represents an α-hydroxyisopropyl group or a hydrogen atom, and at least one A ² is an α-hydroxyisopropyl group. In general formula (9-1), R ⁵¹ represents a hydrogen atom, a hydroxyl group, a linear or branched alkylcarbonyl group having 2 to 6 carbon atoms, or a linear or branched structure having 2 to 6 carbon atoms. The alkoxycarbonyl group of is shown. Furthermore, in general formula (9-2), R ⁵² represents a single bond, a linear or branched alkylene group having 1 to 5 carbon atoms, —O—, —CO—, or —COO—. Moreover, in general formula (9-4), ^R53 and ^R54 show a hydrogen atom or a C1-C6 linear or branched alkyl group mutually independently.

  Specific examples of the benzene compound (1) include α-hydroxyisopropylbenzene, 1,3-bis (α-hydroxyisopropyl) benzene, 1,4-bis (α-hydroxyisopropyl) benzene, and 1,2. , 4-Tris (α-hydroxyisopropyl) benzene, α-hydroxyisopropylbenzenes such as 1,3,5-tris (α-hydroxyisopropyl) benzene; 3-α-hydroxyisopropylphenol, 4-α-hydroxyisopropylphenol , 3,5-bis (α-hydroxyisopropyl) phenol, α-hydroxyisopropylphenols such as 2,4,6-tris (α-hydroxyisopropyl) phenol; 3-α-hydroxyisopropylphenyl methyl ketone, 4-α -Hydroxyisopropyl Nyl methyl ketone, 4-α-hydroxyisopropylphenyl ethyl ketone, 4-α-hydroxyisopropylphenyl n-propyl ketone, 4-α-hydroxyisopropylphenyl isopropyl ketone, 4-α-hydroxyisopropylphenyl n-butyl ketone, 4-α-hydroxyisopropylphenyl · t-butylketone, 4-α-hydroxyisopropylphenyl · n-pentylketone, 3,5-bis (α-hydroxyisopropyl) phenyl · methylketone, 3,5-bis (α-hydroxyisopropyl) ) Α-hydroxyisopropylphenyl alkyl ketones such as phenyl ethyl ketone, 2,4,6-tris (α-hydroxyisopropyl) phenyl methylketone; methyl 3-α-hydroxyisopropylbenzoate , Methyl 4-α-hydroxyisopropyl benzoate, ethyl 4-α-hydroxyisopropyl benzoate, n-propyl 4-α-hydroxyisopropyl benzoate, isopropyl 4-α-hydroxyisopropyl benzoate, 4-α-hydroxyisopropyl benzoate N-butyl acid, t-butyl 4-α-hydroxyisopropylbenzoate, n-pentyl 4-α-hydroxyisopropylbenzoate, methyl 3,5-bis (α-hydroxyisopropyl) benzoate, 3,5-bis ( Alkyl 4-α-hydroxyisopropylbenzoate such as ethyl α-hydroxyisopropyl) benzoate and methyl 2,4,6-tris (α-hydroxyisopropyl) benzoate.

  Specific examples of the diphenyl compound (2) include 3-α-hydroxyisopropylbiphenyl, 4-α-hydroxyisopropylbiphenyl, 3,5-bis (α-hydroxyisopropyl) biphenyl, 3,3 ′. -Bis (α-hydroxyisopropyl) biphenyl, 3,4'-bis (α-hydroxyisopropyl) biphenyl, 4,4'-bis (α-hydroxyisopropyl) biphenyl, 2,4,6-tris (α-hydroxyisopropyl ) Biphenyl, 3,3 ′, 5-tris (α-hydroxyisopropyl) biphenyl, 3,4 ′, 5-tris (α-hydroxyisopropyl) biphenyl, 2,3 ′, 4,6, -tetrakis (α-hydroxy) Isopropyl) biphenyl, 2,4,4 ′, 6, -tetrakis (α-hydroxyisopropyl) (Lopyl) biphenyl, 3,3 ′, 5,5′-tetrakis (α-hydroxyisopropyl) biphenyl, 2,3 ′, 4,5 ′, 6-pentakis (α-hydroxyisopropyl) biphenyl, 2,2 ′, 4 , 4 ′, 6,6′-hexakis (α-hydroxyisopropyl) biphenyl and the like α-hydroxyisopropylbiphenyls; 3-α-hydroxyisopropyldiphenylmethane, 4-α-hydroxyisopropyldiphenylmethane, 1- (4-α-hydroxy) Isopropylphenyl) -2-phenylethane, 1- (4-α-hydroxyisopropylphenyl) -2-phenylpropane, 2- (4-α-hydroxyisopropylphenyl) -2-phenylpropane, 1- (4-α- Hydroxyisopropylphenyl) -3-phenylpropane, 1- ( -Α-hydroxyisopropylphenyl) -4-phenylbutane, 1- (4-α-hydroxyisopropylphenyl) -5-phenylpentane, 3,5-bis (α-hydroxyisopropyldiphenylmethane, 3,3'-bis (α -Hydroxyisopropyl) diphenylmethane, 3,4'-bis (α-hydroxyisopropyl) diphenylmethane, 4,4'-bis (α-hydroxyisopropyl) diphenylmethane, 1,2-bis (4-α-hydroxyisopropylphenyl) ethane, 1,2-bis (4-α-hydroxypropylphenyl) propane, 2,2-bis (4-α-hydroxypropylphenyl) propane, 1,3-bis (4-α-hydroxypropylphenyl) propane, 2, 4,6-Tris (α-hydroxyisopropyl) dipheny Methane, 3,3 ′, 5-tris (α-hydroxyisopropyl) diphenylmethane, 3,4 ′, 5-tris (α-hydroxyisopropyl) diphenylmethane, 2,3 ′, 4,6-tetrakis (α-hydroxyisopropyl) Diphenylmethane, 2,4,4 ′, 6-tetrakis (α-hydroxyisopropyl) diphenylmethane, 3,3 ′, 5,5′-tetrakis (α-hydroxyisopropyl) diphenylmethane, 2,3 ′, 4,5 ′, 6 Α-hydroxyisopropyldiphenylalkanes such as pentakis (α-hydroxyisopropyl) diphenylmethane, 2,2 ′, 4,4 ′, 6,6′-hexakis (α-hydroxyisopropyl) diphenylmethane; 3-α-hydroxyisopropyldiphenyl ether 4-alpha-hydroxyisopropyl Diphenyl ether, 3,5-bis (α-hydroxyisopropyl) diphenyl ether, 3,3′-bis (α-hydroxyisopropyl) diphenyl ether, 3,4′-bis (α-hydroxyisopropyl) diphenyl ether, 4,4′-bis ( α-hydroxyisopropyl) diphenyl ether, 2,4,6-tris (α-hydroxyisopropyl) diphenyl ether, 3,3 ′, 5-tris (α-hydroxyisopropyl) diphenyl ether, 3,4 ′, 5-tris (α-hydroxy) Isopropyl) diphenyl ether, 2,3 ′, 4,6-tetrakis (α-hydroxyisopropyl) diphenyl ether, 2,4,4 ′, 6-tetrakis (α-hydroxyisopropyl) diphenyl ether, 3,3 ′, 5,5′- Tetrakis ( -Hydroxyisopropyl) diphenyl ether, 2,3 ′, 4,5 ′, 6-pentakis (α-hydroxyisopropyl) diphenyl ether, 2,2 ′, 4,4 ′, 6,6′-hexakis (α-hydroxyisopropyl) diphenyl ether Α-hydroxyisopropyl diphenyl ethers such as 3-α-hydroxyisopropyl diphenyl ketone, 4-α-hydroxyisopropyl diphenyl ketone, 3,5-bis (α-hydroxyisopropyl) diphenyl ketone, 3,3′-bis (α- Hydroxyisopropyl) diphenyl ketone, 3,4'-bis (α-hydroxyisopropyl) diphenyl ketone, 4,4′-bis (α-hydroxyisopropyl) diphenyl ketone, 2,4,6-tris (α-hydroxyisopropyl) diphenyl ketone 3,3 ′, 5-tris (α-hydroxyisopropyl) diphenyl ketone, 3,4 ′, 5-tris (α-hydroxyisopropyl) diphenyl ketone, 2,3 ′, 4,6-tetrakis (α-hydroxy) Isopropyl) diphenyl ketone, 2,4,4 ′, 6-tetrakis (α-hydroxyisopropyl) diphenyl ketone, 3,3 ′, 5,5′-tetrakis (α-hydroxyisopropyl) diphenyl ketone, 2,3 ′, 4 , 5 ′, 6-pentakis (α-hydroxyisopropyl) diphenyl ketone, α-hydroxyisopropyl diphenyl ketones such as 2,2 ′, 4,4 ′, 6,6′-hexakis (α-hydroxyisopropyl) diphenyl ketone; 3-α-hydroxyisopropylbenzoate phenyl, 4-α-hydroxyisopropylbenzoate Acid phenyl, benzoic acid 3-α-hydroxyisopropylphenyl, benzoic acid 4-α-hydroxyisopropylphenyl, 3,5-bis (α-hydroxyisopropyl) benzoic acid phenyl, 3-α-hydroxyisopropylbenzoic acid 3-α- Hydroxyisopropylphenyl, 3-α-hydroxyisopropylbenzoate 4-α-hydroxyisopropylphenyl, 4-α-hydroxyisopropylbenzoate 3-α-hydroxyisopropylphenyl, 4-α-hydroxyisopropylbenzoate 4-α-hydroxyisopropyl Phenyl, 3,5-bis (α-hydroxyisopropyl) phenyl benzoate, phenyl 2,4,6-tris (α-hydroxyisopropyl) benzoate, 3,5-bis (α-hydroxyisopropyl) benzoic acid 3-α -Hydroxy Propylphenyl, 3,5-bis (α-hydroxyisopropyl) benzoate 4-α-hydroxyisopropylphenyl, 3-α-hydroxyisopropylbenzoate 3,5-bis (α-hydroxyisopropyl) phenyl, 4-α-hydroxy Isopropyl benzoate 3,5-bis (α-hydroxyisopropyl) phenyl, benzoate 2,4,6-tris (α-hydroxyisopropyl) phenyl, 2,4,6-tris (α-hydroxyisopropyl) benzoate 3- α-hydroxyisopropylphenyl, 2,4,6-tris (α-hydroxyisopropyl) benzoate 4-α-hydroxyisopropylphenyl, 3,5-bis (α-hydroxyisopropyl) benzoate 3,5-bis (α- Hydroxyisopropyl) phenyl, 3-α-hydroxyisopro 2,4,6-Tris (α-hydroxyisopropyl) phenyl 4-benzoate, 2,4,6-tris (α-hydroxyisopropyl) phenyl 4-benzoate, 2,4,6-tris (α -Hydroxyisopropyl) benzoic acid 3,5-bis (α-hydroxyisopropyl) phenyl, 3,5-bis (α-hydroxyisopropyl) benzoic acid 2,4,6-tris (α-hydroxyisopropyl) phenyl, 2,4 , 6-tris (α-hydroxyisopropyl) benzoic acid 2,4,6-tris (α-hydroxyisopropyl) phenyl and the like α-hydroxyisopropylbenzoic acid phenyls and the like.

  Further, specific examples of the naphthalene compound (3) include 1- (α-hydroxyisopropyl) naphthalene, 2- (α-hydroxyisopropyl) naphthalene, 1,3-bis (α-hydroxyisopropyl) naphthalene, 1,4-bis (α-hydroxyisopropyl) naphthalene, 1,5-bis (α-hydroxyisopropyl) naphthalene, 1,6-bis (α-hydroxyisopropyl) naphthalene, 1,7-bis (α-hydroxyisopropyl) Naphthalene, 2,6-bis (α-hydroxyisopropyl) naphthalene, 2,7-bis (α-hydroxyisopropyl) naphthalene, 1,3,5-tris (α-hydroxyisopropyl) naphthalene, 1,3,6-tris (Α-hydroxyisopropyl) naphthalene, 1,3,7-tris (α- Droxyisopropyl) naphthalene, 1,4,6-tris (α-hydroxyisopropyl) naphthalene, 1,4,7-tris (α-hydroxyisopropyl) naphthalene, 1,3,5,7-tetrakis (α-hydroxyisopropyl) ) Naphthalene and the like.

  Specific examples of the furan compound (4) include 3- (α-hydroxyisopropyl) furan, 2-methyl-3- (α-hydroxyisopropyl) furan, 2-methyl-4- (α- Hydroxyisopropyl) furan, 2-ethyl-4- (α-hydroxyisopropyl) furan, 2-n-propyl-4- (α-hydroxyisopropyl) furan, 2-isopropyl-4- (α-hydroxyisopropyl) furan, 2 -N-butyl-4- (α-hydroxyisopropyl) furan, 2-t-butyl-4- (α-hydroxyisopropyl) furan, 2-n-pentyl-4- (α-hydroxyisopropyl) furan, 2,5 -Dimethyl-3- (α-hydroxyisopropyl) furan, 2,5-diethyl-3- (α-hydroxyisopropyl) furan 3,4-bis (α-hydroxyisopropyl) furan, 2,5-dimethyl-3,4-bis (α-hydroxyisopropyl) furan, 2,5-diethyl-3,4-bis (α-hydroxyisopropyl) Examples include francs.

The acid crosslinking agent (G3) is preferably a compound having two or more free α-hydroxyisopropyl groups, the benzene compound (1) having two or more α-hydroxyisopropyl groups, and two or more α-hydroxyisopropyl groups. The diphenyl compound (2) having, and the naphthalene compound (3) having two or more α-hydroxyisopropyl groups are more preferable, α-hydroxyisopropylbiphenyls having two or more α-hydroxyisopropyl groups, α-hydroxy A naphthalene compound (3) having two or more isopropyl groups is particularly preferred.
The acid cross-linking agent (G3) is usually obtained by a method in which an acetyl group-containing compound such as 1,3-diacetylbenzene is reacted with a Grignard reagent such as CH ₃ MgBr to be methylated, and then hydrolyzed. It can be obtained by a method in which an isopropyl group-containing compound such as diisopropylbenzene is oxidized with oxygen or the like to generate a peroxide and then reduced.

  In the present invention, the blending ratio of the acid crosslinking agent (G) is 1 to 100 parts by weight, preferably 1 to 80 parts by weight, more preferably 2 to 60 parts by weight, particularly preferably 100 parts by weight of the resist base material (R). 4 to 40 parts by weight. When the blending ratio of the acid cross-linking agent (G) is 0.5 parts by weight or more, the effect of suppressing the solubility of the resist film in an alkaline developer is improved, the remaining film ratio is decreased, pattern swelling and meandering are caused. Since generation | occurrence | production can be suppressed, it is preferable, and on the other hand, when it is 50 weight part or less, since the fall of the heat resistance as a resist can be suppressed, it is preferable.

Further, the blending ratio of at least one compound selected from the acid crosslinking agent (G1), the acid crosslinking agent (G2), and the acid crosslinking agent (G3) in the acid crosslinking agent (G) is not particularly limited. Various ranges can be used depending on the type of substrate used when forming the pattern.
In the total acid crosslinking agent component, the alkoxymethylated melamine compound and / or the compound represented by (9-1) to (9-3) is 50 to 99% by weight, preferably 60 to 99% by weight, more preferably 70%. It is preferable that it is -98 weight%, More preferably, it is 80-97 weight%. Since the resolution can be improved by setting the alkoxymethylated melamine compound and / or the compounds represented by (9-1) to (9-3) to 50% by weight or more of the total acid crosslinking agent component, 99 It is preferable to set the weight% or less because the cross-sectional shape of the pattern is easily a rectangular cross-sectional shape.

In the present invention, an acid diffusion control agent (E) having an action of controlling undesired chemical reaction in an unexposed region by controlling diffusion of an acid generated from an acid generator by irradiation in a resist film. You may mix | blend with a radiation sensitive composition. By using such an acid diffusion controller (E), the storage stability of the radiation-sensitive composition is improved. Further, the resolution is improved, and a change in the line width of the resist pattern due to fluctuations in the holding time before electron beam irradiation and the holding time after electron beam irradiation can be suppressed, and the process stability is extremely excellent. Examples of such an acid diffusion controller (E) include electron beam radiation decomposable basic compounds such as a nitrogen atom-containing basic compound, a basic sulfonium compound, and a basic iodonium compound. The acid diffusion controller can be used alone or in combination of two or more.
Examples of the acid diffusion controller include nitrogen-containing organic compounds and basic compounds that decompose upon exposure. Examples of the nitrogen-containing organic compound include the following general formula (10):

（１０）
で表される化合物（以下、「含窒素化合物（Ｉ）」という。）、同一分子内に窒素原子を２個有するジアミノ化合物（以下、「含窒素化合物（ＩＩ）」という。）、窒素原子を３個以上有するポリアミノ化合物や重合体（以下、「含窒素化合物（ＩＩＩ）」という。）、アミド基含有化合物、ウレア化合物、及び含窒素複素環式化合物等を挙げることができる。尚、上記酸拡散制御剤は、１種単独で用いてもよく、２種以上を併用してもよい。

(10)
(Hereinafter referred to as “nitrogen-containing compound (I)”), a diamino compound having two nitrogen atoms in the same molecule (hereinafter referred to as “nitrogen-containing compound (II)”), and a nitrogen atom. Examples thereof include polyamino compounds and polymers having three or more compounds (hereinafter referred to as “nitrogen-containing compound (III)”), amide group-containing compounds, urea compounds, and nitrogen-containing heterocyclic compounds. In addition, the said acid diffusion control agent may be used individually by 1 type, and may use 2 or more types together.

In the general formula (10), R ⁶¹ , R ⁶² and R ⁶³ each independently represent a hydrogen atom, a linear, branched or cyclic alkyl group, an aryl group, or an aralkyl group. The alkyl group, aryl group, or aralkyl group may be unsubstituted or substituted with another functional group such as a hydroxyl group. Here, examples of the linear, branched or cyclic alkyl group include those having 1 to 15 carbon atoms, preferably 1 to 10 carbon atoms, specifically, methyl group, ethyl group, n- Propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, n-pentyl group, neopentyl group, n-hexyl group, texyl group, n-heptyl group, n-octyl group , N-ethylhexyl group, n-nonyl group, n-decyl group and the like. Moreover, as said aryl group, a C6-C12 thing is mentioned, Specifically, a phenyl group, a tolyl group, a xylyl group, a cumenyl group, 1-naphthyl group, etc. are mentioned. Furthermore, examples of the aralkyl group include those having 7 to 19 carbon atoms, preferably 7 to 13 carbon atoms, and specific examples include a benzyl group, an α-methylbenzyl group, a phenethyl group, and a naphthylmethyl group.

  Specific examples of the nitrogen-containing compound (I) include mono-cyclohexane such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-dodecylamine and cyclohexylamine. ) Alkylamines; di-n-butylamine, di-n-pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine , Methyl-n-dodecylamine, di-n-dodecylmethyl, cyclohexylmethylamine, dicyclohexylamine and the like di (cyclo) alkylamines; triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n- Pentylamine, tri-n-hexylamine, tri-n-heptylamine, -Tri (cyclo) alkylamines such as n-octylamine, tri-n-nonylamine, tri-n-decylamine, dimethyl-n-dodecylamine, di-n-dodecylmethylamine, dicyclohexylmethylamine, tricyclohexylamine; Alkanolamines such as monoethanolamine, diethanolamine, triethanolamine; aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine , Aromatic amines such as triphenylamine and 1-naphthylamine.

  Specific examples of the nitrogen-containing compound (II) include ethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, Tetramethylenediamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenylamine, 2,2-bis (4-aminophenyl) ) Propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 2- (4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl)- 2- (4-Hydroxyphenyl) propane, 1,4-bis [1- (4-aminophenyl) -1-methylethyl] benzene, and 1,3-bis [1- (4-aminophenyl) -1-methylethyl] benzene, and the like.

Specific examples of the nitrogen-containing compound (III) include polyethyleneimine, polyallylamine, N- (2-dimethylaminoethyl) acrylamide polymer, and the like.
Specific examples of the amide group-containing compound include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N- And methylpyrrolidone.

  Specific examples of the urea compound include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tri- Examples thereof include n-butylthiourea.

  Specific examples of the nitrogen-containing heterocyclic compound include imidazoles such as imidazole, benzimidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, 2-phenylbenzimidazole; pyridine, 2-methylpyridine. 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, 2-methyl-4-phenylpyridine, nicotine, nicotinic acid, nicotinamide, quinoline, 8-oxyquinoline And pyridines such as acridine; and pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, morpholine, 4-methylmorpholine, piperazine, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2.2.2. ] Octane etc. It can gel.

（１１−１）
で表されるスルホニウム化合物、及び下記一般式（１１−２）： Moreover, as a basic compound decomposed | disassembled by the said exposure, the following general formula (11-1):

(11-1)
And the following general formula (11-2):

（１１−２）
で表されるヨードニウム化合物等を挙げることができる。

(11-2)
The iodonium compound etc. which are represented by these can be mentioned.

In the general formulas (11-1) and (11-2), R ⁷¹ , R ⁷² , R ⁷³ , R ⁷⁴ and R ⁷⁵ are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or 1 carbon atom. -6 alkoxy groups, hydroxyl groups or halogen atoms. Z ⁻ represents HO ⁻ , R—COO ⁻ (wherein R represents an alkyl group having 1 to 6 carbon atoms, an aryl group having 1 to 6 carbon atoms, or an alkaryl group having 1 to 6 carbon atoms) or the following general formula. (11-3):

（１１−３）
で表されるアニオンを示す。

(11-3)
An anion represented by

  Specific examples of the basic compound that decomposes upon exposure include triphenylsulfonium hydroxide, triphenylsulfonium acetate, triphenylsulfonium salicylate, diphenyl-4-hydroxyphenylsulfonium hydroxide, and diphenyl-4-hydroxyphenyl. Sulfonium acetate, diphenyl-4-hydroxyphenylsulfonium salicylate, bis (4-t-butylphenyl) iodonium hydroxide, bis (4-t-butylphenyl) iodonium acetate, bis (4-t-butylphenyl) iodonium hydro Oxide, bis (4-t-butylphenyl) iodonium acetate, bis (4-t-butylphenyl) iodonium salicylate, 4-t-butylphenyl 4- hydroxyphenyl iodonium hydroxide, 4-t-butylphenyl-4-hydroxyphenyl iodonium acetate, include 4-t-butylphenyl-4-hydroxyphenyl iodonium salicylate and the like.

  The blending amount of the acid diffusion controller (E) is preferably 0.001 to 50% by weight, more preferably 0.001 to 10% by weight, still more preferably 0.001 to 5% by weight, based on the total weight of the solid component. 0.001 to 3% by weight is particularly preferred. Within the above range, it is possible to prevent degradation in resolution, pattern shape, dimensional fidelity, and the like. Furthermore, even if the holding time from electron beam irradiation to heating after radiation irradiation becomes longer, the shape of the pattern upper layer portion does not deteriorate. Further, when the blending amount is 10% by weight or less, it is possible to prevent a decrease in sensitivity, developability of an unexposed portion, and the like. Further, by using such an acid diffusion control agent, the storage stability of the radiation-sensitive composition is improved, the resolution is improved, and the holding time before irradiation and the holding time after irradiation are reduced. Changes in the line width of the resist pattern due to fluctuations can be suppressed, and the process stability is extremely excellent.

  In the negative radiation-sensitive composition of the present invention, as long as the purpose of the present invention is not hindered, as other components (F), a dissolution accelerator, a dissolution control agent other than the present invention, One or more additives such as a sensitizer, a surfactant, and an organic carboxylic acid or an oxo acid of phosphorus or a derivative thereof can be added.

[1] Dissolution Accelerator A low molecular weight dissolution accelerator increases the solubility of a cyclic compound during development when the solubility of a resist base material in an alkali or other developer is too low, and moderately increases the dissolution rate of a cyclic compound during development. It is a component which has the effect | action to make it use in the range which does not impair the effect of this invention. Examples of the dissolution accelerator include low molecular weight phenolic compounds such as bisphenols and tris (hydroxyphenyl) methane. These dissolution promoters can be used alone or in admixture of two or more. The blending amount of the dissolution accelerator is appropriately adjusted according to the type of the resist base used, but is preferably 0 to 100 parts by weight, preferably 0 to 30 parts by weight per 100 parts by weight of the resist base. More preferably, it is 0-10 weight part, More preferably, it is 0-2 weight part.

[2] Dissolution inhibitor other than the present invention The dissolution inhibitor other than the present invention controls the solubility when the resist base material is too soluble in a developing solution such as an alkali, and dissolves during development. It is a component that has the effect of moderately reducing the speed. As such a dissolution inhibitor, those which do not chemically change in steps such as baking of resist film, irradiation with radiation, and development are preferable.
Examples of the dissolution inhibitor other than the present invention include aromatic hydrocarbons such as naphthalene, phenanthrene, anthracene, and acenaphthene; ketones such as acetophenone, benzophenone, phenylnaphthyl ketone, and benzoin; methylphenylsulfone, diphenylsulfone, and diphenylsulfone Examples include sulfones such as naphthyl sulfone. Further, for example, a low-molecular compound having a molecular weight of 1000 or less in which an acid-dissociable functional group is introduced into a low-molecular compound having two or more phenolic hydroxyl groups or one or more carboxy groups can be used. The acid-dissociable functional group is eliminated by the acid generated from the agent, so that the solubility in an alkali developer is improved, and the sensitivity of the resist may be lowered. These dissolution control agents can be used alone or in combination of two or more.
The blending amount of the dissolution inhibitor other than the present invention is appropriately adjusted according to the type of the resist base (R) to be used, and preferably 0 to 100 parts by weight per 100 parts by weight of the resist base (R). The amount is preferably 0 to 30 parts by weight, more preferably 0 to 10 parts by weight, and still more preferably 0 to 2 parts by weight.

[3] Sensitizer The sensitizer absorbs the energy of the irradiated radiation and transmits the energy to the acid generator (C), thereby increasing the amount of acid generated. It is a component that improves the apparent sensitivity. Examples of such sensitizers include, but are not limited to, benzophenones, biacetyls, pyrenes, phenothiazines, and fluorenes.
These sensitizers can be used alone or in combination of two or more. Although the compounding quantity of a sensitizer is adjusted suitably according to the kind of resist base material (R) to be used, it is 0-100 weight part per 100 weight part of resist base material (R) shown by Formula (1). Is preferably 0 to 30 parts by weight, more preferably 0 to 10 parts by weight, still more preferably 0 to 2 parts by weight.

[4] Surfactant The surfactant is a component having an effect of improving the coating property and striation of the negative radiation-sensitive composition of the present invention, the developability of the resist, and the like. Such a surfactant may be anionic, cationic, nonionic or amphoteric. A preferred surfactant is a nonionic surfactant. Nonionic surfactants have better affinity with the solvent used in the production of the radiation-sensitive composition and are more effective. Examples of nonionic surfactants include polyoxyethylene higher alkyl ethers, polyoxyethylene higher alkyl phenyl ethers and higher fatty acid diesters of polyethylene glycol, but are not particularly limited. Commercially available products include the following product names: F-top (manufactured by Gemco), Mega-Fac (manufactured by Dainippon Ink and Chemicals), Florard (manufactured by Sumitomo 3M), Asahi Guard, Surflon (manufactured by Asahi Glass Co., Ltd.), Examples include Pepol (manufactured by Toho Chemical Industry Co., Ltd.), KP (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow (manufactured by Kyoeisha Yushi Chemical Co., Ltd.)
The compounding amount of the surfactant is appropriately adjusted according to the type of the resist base material (R) to be used, but is preferably 0 to 100 parts by weight, preferably 0 to 100 parts by weight per 100 parts by weight of the resist base material (R). 30 parts by weight, more preferably 0 to 10 parts by weight, still more preferably 0 to 2 parts by weight.

[5] Organic carboxylic acid or phosphorous oxo acid or derivative thereof For the purpose of preventing sensitivity deterioration or improving resist pattern shape, retention stability, etc., organic carboxylic acid or phosphorous oxo acid or derivative thereof as an optional component Can be contained. In addition, it can be used in combination with an acid diffusion controller, or may be used alone. 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 such as diphenyl ester phosphoric acid or derivatives thereof such as phosphonic acid, phosphonic acid dimethyl ester, phosphonic acid di- Derivatives such as n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, phosphonic acid dibenzyl ester, etc., phosphonic acid or their esters, phosphinic acid, phosphinic acid such as phenylphosphinic acid, and derivatives thereof Of these, phosphonic acid is particularly preferred.
The organic carboxylic acid or phosphorus oxo acid or derivative thereof may be used alone or in combination of two or more. The amount of the organic carboxylic acid or phosphorus oxo acid or derivative thereof is appropriately adjusted according to the type of the resist base (R) to be used, but is 0 to 100 weights per 100 parts by weight of the resist base (R). Parts, preferably 0 to 30 parts by weight, more preferably 0 to 10 parts by weight, still more preferably 0 to 2 parts by weight.

[6] The dissolution inhibitor, sensitizer, surfactant, and other additives other than organic carboxylic acid or phosphorus oxo acid or derivatives thereof. One or more additives other than the above-described dissolution inhibitor, sensitizer, and surfactant can be blended as necessary within a range that does not impair the purpose. Examples of such additives include dyes, pigments, and adhesion aids. For example, it is preferable to add a dye or a pigment because the latent image in the exposed area can be visualized and the influence of halation during exposure can be reduced. In addition, it is preferable to add an adhesion assistant because the adhesion to the substrate can be improved. Furthermore, examples of other additives include an antihalation agent, a storage stabilizer, an antifoaming agent, a shape improving agent, and the like, specifically 4-hydroxy-4′-methylchalcone.

Formulation of negative radiation sensitive composition of the present invention (dissolution inhibitor / resist substrate (R) / acid generator (C) / acid crosslinking agent (G) / acid diffusion controller (E) / optional component (F )) Is weight percent based on solids, preferably 10-50 / 50-90 / 0.001-50 / 0.5-50 / 0.01-50 / 0-50,
More preferably
10-50 / 50-90 / 0.001-50 / 0.5-40 / 0.01-5 / 0-15,
More preferably, 12 to 35/60 to 70/10 to 25/1 to 30 / 0.01 to 3/0 to 1.
Particularly preferably, it is 12.5 to 17.5 / 60 to 70/10 to 25/2 to 20 / 0.01 to 3/0. When the above composition is used, the performance such as sensitivity, resolution and alkali developability is excellent.

  The negative radiation-sensitive composition of the present invention is usually prepared by dissolving each component in a solvent to form a uniform solution at the time of use, and then filtering with a filter having a pore size of about 0.2 μm as necessary. Prepared.

  Examples of the solvent used in the preparation of the negative radiation-sensitive composition of the present invention include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, ethylene glycol mono- ethylene glycol monoalkyl ether acetates such as n-butyl ether acetate; ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono- n-propyl ether acetate, propylene glycol mono-n-butyl ether acetate Propylene glycol monoalkyl ether acetates such as; propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether; methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, n-amyl lactate, etc. Lactate esters; aliphatic carboxylic acid esters such as methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, n-amyl acetate, n-hexyl acetate, methyl propionate, ethyl propionate; Methyl propionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl 3-methoxy-2-methylpropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxy Other esters such as butyl acetate, butyl 3-methoxy-3-methylpropionate, butyl 3-methoxy-3-methylbutyrate, methyl acetoacetate, methyl pyruvate and ethyl pyruvate; aromatic carbonization such as toluene and xylene Hydrogen; ketones such as 2-heptanone, 3-heptanone, 4-heptanone, cyclopentanone, cyclohexanone; N, N-dimethylformamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, etc. Amides; lactones such as γ-lactone can be exemplified, but are not particularly limited. These solvents can be used alone or in combination of two or more.

  The negative radiation sensitive composition of the present invention can contain a resin that is soluble in an alkaline aqueous solution as long as the object of the present invention is not impaired. Resins that are soluble in an alkaline aqueous solution include novolak resins, polyvinylphenols, polyacrylic acid, polyvinyl alcohol, styrene-maleic anhydride resins, and heavy polymers containing acrylic acid, vinyl alcohol, or vinyl phenol as monomer units. A combination, or a derivative thereof may be used. The blending amount of the resin soluble in the alkaline aqueous solution is appropriately adjusted according to the kind of the cyclic compound to be used, but is preferably 0 to 30 parts by weight, more preferably 0 to 10 parts per 100 parts by weight of the cyclic compound. Parts by weight, more preferably 0 to 5 parts by weight, particularly preferably 0 parts by weight.

[Method of forming resist pattern]
The present invention uses the negative radiation-sensitive composition of the present invention to form a resist film on a substrate, to expose the resist film, and to develop the resist film to form a resist pattern The present invention relates to a resist pattern forming method including a process. The resist pattern of the present invention can also be formed as an upper layer resist in a multilayer resist process.
In order to form a resist pattern, a resist film is formed by applying the radiation-sensitive composition of the present invention on a conventionally known substrate by coating means such as spin coating, cast coating, roll coating or the like. The conventionally known substrate is not particularly limited, and examples thereof include a substrate for electronic parts and a substrate on which a predetermined wiring pattern is formed. More specifically, a silicon wafer, a metal substrate such as copper, chromium, iron, and aluminum, a glass substrate, and the like can be given. Examples of the wiring pattern material include copper, aluminum, nickel, and gold. If necessary, an inorganic and / or organic film may be provided on the substrate. An inorganic antireflection film (inorganic BARC) is an example of the inorganic film. Examples of the organic film include an organic antireflection film (organic BARC). Surface treatment with hexamethylene disilazane or the like may be performed.
Next, the coated substrate is heated as necessary. Although heating conditions change with the compounding composition etc. of a radiation sensitive composition, 20-250 degreeC is preferable, More preferably, it is 20-150 degreeC. Heating may improve the adhesion of the resist to the substrate, which is preferable. Next, the resist film is exposed to a desired pattern with any radiation selected from the group consisting of visible light, ultraviolet light, excimer laser, electron beam, extreme ultraviolet light (EUV), X-ray, and ion beam. The exposure conditions and the like are appropriately selected according to the composition of the radiation sensitive composition. In the present invention, in order to stably form a high-precision fine pattern in exposure, heating is preferably performed after irradiation with radiation. Although heating conditions change with the compounding composition etc. of a radiation sensitive composition, 20-250 degreeC is preferable, More preferably, it is 20-150 degreeC.

Next, the exposed resist film is developed with an alkaline developer to form a predetermined resist pattern. Examples of the alkaline developer include alkaline such as mono-, di- or trialkylamines, mono-, di- or trialkanolamines, heterocyclic amines, tetramethylammonium hydroxide (TMAH), choline and the like. An alkaline aqueous solution in which one or more compounds are dissolved so as to have a concentration of preferably 1 to 10% by mass, more preferably 1 to 5% by mass is used. When the concentration of the alkaline aqueous solution is 10% by mass or less, it is preferable because the exposed portion can be prevented from being dissolved in the developer.
In addition, an appropriate amount of alcohols such as methanol, ethanol, isopropyl alcohol, and the surfactant can be added to the alkaline developer. Of these, it is particularly preferable to add 10 to 30% by mass of isopropyl alcohol. This is preferable since the wettability of the developer with respect to the resist can be improved. In addition, when using the developing solution which consists of such alkaline aqueous solution, generally it wash | cleans with water after image development.

After forming the resist pattern, the pattern wiring board is obtained by etching. The etching can be performed by a known method such as dry etching using plasma gas and wet etching using an alkali solution, a cupric chloride solution, a ferric chloride solution, or the like.
Plating can be performed after forming the resist pattern. Examples of the plating method include copper plating, solder plating, nickel plating, and gold plating.
The residual resist pattern after etching can be peeled off with an organic solvent or a stronger alkaline aqueous solution than the alkaline aqueous solution used for development. Examples of the organic solvent include PGMEA (propylene glycol monomethyl ether acetate), PGME (propylene glycol monomethyl ether), EL (ethyl lactate) and the like. As the strong alkaline aqueous solution, for example, 1 to 20% by mass of sodium hydroxide aqueous solution or 1-20 mass% potassium hydroxide aqueous solution is mentioned. Examples of the peeling method include a dipping method and a spray method. In addition, the wiring board on which the resist pattern is formed may be a multilayer wiring board or may have a small diameter through hole.
The wiring board obtained by the present invention can also be formed by a method of depositing a metal in vacuum after forming a resist pattern and then dissolving the resist pattern with a solution, that is, a lift-off method.

Hereinafter, the embodiment of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. In the following synthesis examples, the structure of the compound was confirmed by ¹ H-NMR measurement.

<Synthesis example> Synthesis synthesis example 1 of cyclic compound (A)
Synthesis of CR-1 A well-dried, nitrogen-substituted dropping funnel, Jim Roth condenser, thermometer, and four-necked flask (1000 mL) equipped with a stirring blade were placed under a nitrogen stream under resorcinol (manufactured by Kanto Chemical Co., Ltd.) 22 g, 0.2 mol), 4-n-propylcyclohexylbenzaldehyde (46 g, 0.2 mol), and dehydrated ethanol (200 ml) were added to prepare an ethanol solution. This solution was heated to 85 ° C. with a mantle heater while stirring. Next, 75 ml of concentrated hydrochloric acid (35%) was added dropwise over 30 minutes using a dropping funnel, and then stirred at 85 ° C. for 3 hours. After the completion of the reaction, the mixture was allowed to cool and allowed to reach room temperature, and then cooled in an ice bath. After standing for 1 hour, pale yellow target crude crystals were produced, which were filtered off. The crude crystals were washed twice with 500 ml of methanol, filtered and dried in vacuo to obtain the desired product (hereinafter referred to as CR-1) (58 g, yield 91%).
As a result of analyzing the structure of this compound by LC-MS, the molecular weight of the target product was 1289. Moreover, the chemical shift value (δppm, TMS standard) of ¹ H-NMR in a heavy dimethyl sulfoxide solvent is 0.9 to 1.9 (m, 68H), 5.5 to 5.6 (d, 4H), 6 0.0 to 6.8 (m, 24H) and 8.4 to 8.5 (m, 8H).

（ＣＲ−１）

(CR-1)

Synthesis example 2
Synthesis of CR-2 Synthesis was performed in the same manner as CR-1 except that 4-n-propylcyclohexylbenzaldehyde in the synthesis example of CR-1 was replaced with 4-n-pentylcyclohexylbenzaldehyde. As a result, CR-2 (63.0 g, yield 90%) was obtained.
As a result of analyzing the structure of this compound by LC-MS, the molecular weight of the target product was 1401. The chemical shift value (δppm, TMS standard) of ¹ H-NMR in the heavy dimethyl sulfoxide solvent of the obtained product is 0.9 to 1.9 (m, 84H), 5.5 to 5.6 ( d, 4H), 6.0-6.8 (m, 24H), 8.4-8.5 (m, 8H).

（ＣＲ−２）

(CR-2)

Synthesis example 3
Synthesis of CR-3 Synthesis was performed in the same manner as CR-1 except that 4-isopropylbenzaldehyde in the synthesis example of CR-1 was replaced with 4-cyclohexylbenzaldehyde (46.0 g, 0.2 mol). As a result, CR-3 (50 g, yield 91%) was obtained.
As a result of analyzing the structure of this compound by LC-MS, the molecular weight of the target product was 1121. The chemical shift value (δppm, TMS standard) of ¹ H-NMR in deuterated dimethyl sulfoxide solvent is 0.8 to 1.9 (m, 44H), 5.5 to 5.6 (d, 4H), 6 0.0 to 6.8 (m, 24H) and 8.4 to 8.5 (m, 8H).

（ＣＲ−３）

(CR-3)

Examples 1-3 and Comparative Examples 1-5
Patterning test The ingredients listed in Table 1 were mixed to form a uniform solution, and then filtered through a Teflon (registered trademark) membrane filter with a pore size of 0.1 μm to prepare a radiation-sensitive composition. Went. The results are shown in Table 2.
(1) Evaluation of sensitivity After a resist composition was spin-coated on a clean silicon wafer, pre-exposure baking (PB) was performed in an oven to form a resist film having a thickness of 60 nm. The resist film was irradiated with an electron beam with a line-and-space setting of 1: 1 at 50 nm intervals using an electron beam drawing apparatus (ELS-7500, manufactured by Elionix Co., Ltd.). After irradiation, each was heated at a predetermined temperature for 90 seconds and developed in a 2.38 wt% TMAH aqueous solution for 60 seconds. Thereafter, it was washed with water for 30 seconds and dried to form a negative resist pattern. The obtained line and space was observed with a scanning electron microscope (S-4800, manufactured by Hitachi High-Technology Corporation). The dose amount (μC / cm ² ) at that time was defined as sensitivity.

(2) Evaluation of Line Edge Roughness (LER) Hitachi Semiconductor's SEM Terminal PC V5 offline length measurement software at (300 points in the length direction (0.75 μm) of 1: 1 line and space at 50 nm intervals (( Using Hitachi Science Systems Co., Ltd.), the distance between the edge and the reference line was measured. The standard deviation (3σ) was calculated from the measurement result.
A: LER (3σ) ≦ 3.5 nm (good LER)
C: 3.5 nm <LER (3σ) (not good LER)

Dissolution inhibitor D-1: Benzoin (Kanto Chemical Co., Inc.)
D-2: Anthracure UVS-1331 (9,10-dibutoxyanthracene) (Kawasaki Chemical Industry Co., Ltd.)
(C) Acid generator P-1: Triphenylbenzenesulfonium nonafluorobutanesulfonate (Midori Chemical Co., Ltd.)
P-2: Triphenylbenzenesulfonium trifluoromethanesulfonate (Midori Chemical Co., Ltd.)
(G) Acid crosslinking agent C-1 Nicalak MW-100LM (Sanwa Chemical Co., Ltd.)
C-2 Nicarak MX-270 (Sanwa Chemical Co., Ltd.)
(E) Acid diffusion control agent
Q-1 Trioctylamine (Tokyo Chemical Industry Co., Ltd.)

solvent
S-1 Propylene glycol monomethyl ether (Tokyo Chemical Industry Co., Ltd.)

ＰＥＢ：電子線照射後に加熱する際の温度

PEB: Temperature when heating after electron beam irradiation

  The present invention relates to a dissolution inhibitor represented by a specific chemical structural formula useful as an acid-amplified non-polymer resist material, a negative radiation-sensitive composition containing the same, and a resist pattern forming method using the composition Is preferably used.

Claims (5)

A radiation-sensitive composition comprising a dissolution inhibitor represented by the following formula (1), a resist base material (R) and a solvent, comprising 1 to 80% by weight of a solid component and 20 to 99% by weight of a solvent, wherein the dissolution A radiation-sensitive composition in which the inhibitor is 10 to 50% by weight based on the total weight of the solid components.

(In formula (1), R ¹ is independently a linear or branched alkyl group having 3 to 12 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms, and p is an integer of 1 to 5) .) Furthermore, acid generation that directly or indirectly generates an acid upon irradiation with radiation selected from the group consisting of visible light, ultraviolet light, excimer laser, electron beam, extreme ultraviolet light (EUV), X-ray, and ion beam. claim 1 the radiation-sensitive composition according comprising agent (C). Further, according to claim 1 radiation-sensitive composition further comprising an acid crosslinking agent (G). Furthermore, radiation-sensitive composition of claim 1 further comprising an acid diffusion controller (E). A step of forming a resist film on a substrate, a step of exposing the resist film, and a step of developing the resist film to form a resist pattern using the radiation-sensitive composition according to any one of claims 1 to 4. A resist pattern forming method including the step of: