JPH09143146A - Spiroindanephenolsufonic ester and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound useful as an acid producer for a positive type resist material for high energy rays excellent in sensitivity and resolution. SOLUTION: This spiroindanephenolsulfonic ester is represented by the formula R<1> is a (substituted)alkyl or a (substituted)aryl; R<2> is H, an alkyl, an alkoxy, nitro or a halogen; (m) is 1 or 2; (n) is an integer of 1-3; [(n)+(m)] is <=4}, e.g. 6,6'-dihydroxy-3,3,3',3'-tetramethyl-1,1'-spiroindane. The compound represented by the formula is obtained by carrying out the dehydrochlorinating reaction of, e.g. the spiroinadanephenols and sulfonyl chlorides. The reaction is preferably carried out in the presence of a base, especially organic bases such as triethylamine as a hydrochloric acid capturing agent. An alkali-soluble resin, a dissolution inhibitor and the compound represented by the formula as an acid producer are used as components to afford a positive type photoresist material.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel spirobiindanephenol sulfonate and a resist material containing the same. Particularly, in a positive photoresist material that generates an acidic substance during exposure to decompose the dissolution inhibitor of the photoresist and makes the exposed portion soluble in an alkali developing solution, spirobiindanephenol sulfonate as an acid generator. The present invention relates to a positive resist material suitable for fine processing using.

[0002]

2. Description of the Related Art Conventionally, with the high integration and high density of LSIs (high-density integrated circuits), miniaturization of pattern rules has been demanded, but light emitted from a light source used in a normal optical exposure technique. Has a long wavelength and is not a single wavelength, so there is a limit to the miniaturization of the pattern rule. Therefore, g-line (wavelength 436 nm) or i emitted from the ultra-high pressure mercury lamp
The use of a line (wavelength 365 nm) as a light source has also been considered. However, even in these cases, the resolution of the pattern rule is limited to about 0.5 μm, and the LSI that can be manufactured by this is only the integration degree of about 16 Mbit DRAM. Therefore, in recent years, far-ultraviolet lithography, which has a shorter wavelength than g-line and i-line, is regarded as promising. It is also possible to form a pattern rule of 0.1 to 0.3 μm by using deep-UV lithography, and when a resist material having low light absorption is used, a sidewall that is almost vertical to the substrate is formed. It is possible to form patterns that have. Furthermore, it is also possible to transfer patterns at one time, which is superior to lithography using electron beams in that the pattern formation processing efficiency (throughput) is higher. Further, since it becomes possible to use a KrF excimer laser having a high luminous intensity as a light source for far-ultraviolet rays, a resist material having a particularly small absorbance and a high sensitivity is used from the viewpoint of mass-producing an LSI using various light sources. Is required.

[0003] In response to such requirements, a chemically amplified resist material which has a sensitivity equal to or higher than that of a conventional high-sensitivity resist material and has high resolution and dry etching resistance and which is produced by using an acid as a catalyst has been developed. (For example, Liu et al., Journal of Vacuum Science and Technology (Liu, et. Al., J. Vac.S.
ci. Techno. B6 , 379 (1988))], Novolak resin, melamine compound and acid generator by Shipley Co.
Chemically amplified negative resist material consisting of components (trade name
SAL601ER7) has already been commercialized. However, LSI
When using a negative resist material in the manufacturing process of
Although it is easy to form a wiring and a gate portion, there is a drawback that it is difficult to form a contact hole that requires fine processing. Moreover, when the conventionally proposed chemically amplified positive type resist material is used as it is for pattern formation by deep ultraviolet rays, electron beams or X-rays, the solubility of the resist surface is lowered and the pattern after development is over. Since it tends to be hung, it becomes difficult to control the dimensions of the pattern, and not only impairs the dimensional controllability during substrate processing by dry etching, but also has the drawback that the pattern tends to collapse (for example, KG
Chiong, et. Al., J. Vac. Sci. Techno. B7, 1771 (1
989)].

At present, there is a strong demand for the development of a chemically amplified positive resist material that solves the above problems. In response to such a demand, a chemically amplified positive type resist material in which an onium salt is added to a poly (butoxycarbonyloxystyrene) resin in which a hydroxyl group of a poly (hydroxystyrene) derivative is protected with a tert-butoxycarbonyl group has been proposed. [For example, Ito, et. Al., Polymers in Electoro
nics, ACS Synposium Series, 242, 11 (1984)]. However, the above-mentioned onium salt contains antimony as a metal component, and when a resist material containing the onium salt is used, not only the substrate is contaminated, but also the resist material after the irradiation with far-ultraviolet rays, etc. There is a problem that the change is extremely large.

Further, a positive type resist material for deep ultraviolet rays, which comprises a poly (p-styreneoxytetrahydropyranyl) resin as a main component and an acid generator added thereto, has been proposed (Ueno et al., 36th session). Japan Society of Applied Physics
1989, 1p-k-7). However, the above-mentioned positive resist material has a drawback that it is easy to reverse from a positive type to a negative type with respect to deep ultraviolet rays, electron beams or X-rays. 2 consisting of a resin in which the above hydroxyl group is protected with a protecting group and an acid generator 2
Component type positive resist materials are required to decompose many protecting groups in order to be dissolved in a developing solution.
There are problems that the film thickness of the resist is changed in the manufacturing process, and stress and bubbles are easily generated in the film.

As a chemically amplified positive resist material that overcomes the problems of the above-described two-component positive resist material, a three-component positive resist material comprising an alkali-soluble resin, a dissolution inhibitor and an acid generator is used. Is being developed. As a three-component positive resist material, a resist material containing a novolak resin, an acetal compound as a dissolution inhibitor, and an acid generator (RAY / Hoechst)
Have been developed for X-ray lithography. However, since the resist material undergoes chemical amplification at room temperature, its resist sensitivity greatly depends on the time from X-ray exposure to development. Therefore, since it is necessary to control the time very strictly, it is difficult to stabilize the dimension of the pattern, and the absorption of the KrF excimer laser (wavelength 248 nm) is large, and the laser is used. It is unsuitable for lithographic use.

Most of the compounds having a tert-butoxycarbonyloxy group have the effect of inhibiting the solubility of the novolak resin, that is, the tert-butoxycarbonyloxy group has the effect of inhibiting the dissolution of the novolak resin. It has been known. From such a viewpoint, a three-component positive resist material composed of a novolak resin, a dissolution inhibitor in which a tert-butoxycarbonyl group is introduced into bisphenol A, and pyrogallol methanesulfonic acid ester has been proposed [Schlegel et al., 19
90th Spring, 37th Joint Lecture Meeting of Japan Society of Applied Physics, 2
8p-ZE-4]. However, it is difficult to put this system into practical use because the novolak resin absorbs a large amount of light.

Generally, when chemical amplification is performed, heat treatment is often required after exposure. In this case, although the number of steps is increased as compared with a resist material that is chemically amplified at room temperature, it is not necessary to strictly control the time from exposure to development, so that the resist characteristics are stable.
In addition, in a three-component chemically amplified positive resist composition comprising a resin, a dissolution inhibitor and an acid generator, the dissolution inhibitor controls the dissolution rate of the resist film in an alkali developer [(high energy ray (Dissolution rate of the part irradiated with) / (dissolution rate of non-irradiated part)
It is known that (increasing the dissolution rate ratio)] has a great influence on the performance as a resist material. For this purpose, the dissolution inhibitor in the resist film portion when irradiated with high energy rays such as ultraviolet rays is rapidly decomposed, and an acidic substance is generated to change it to a substance that dissolves in an alkaline developer. Therefore, it is important to develop acid generators.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a high-sensitivity and high-resolution positive photoresist material for high energy rays, and to develop an excellent acid generator for that purpose. That is.

[0010]

Means for Solving the Problems As a result of intensive studies on the above problems, the present inventors have found that a certain kind of spirobiindanephenolsulfonic acid ester has excellent performance, and have completed the present invention. I arrived. That is, the present invention relates to a spirobiindanephenolsulfonic acid ester represented by the following general formula (1) (Chemical Formula 2), which is a positive photoresist containing an alkali-soluble resin, a dissolution inhibitor and an acid generator. In the material, the present invention relates to a positive photoresist material containing spirobiindanephenol sulfonate represented by the general formula (1) as the acid generator.

[0011]

Embedded image (In the formula, R ¹ represents an optionally substituted alkyl group or an optionally substituted aryl group, R ² represents a hydrogen atom, an alkyl group, an alkoxy group, a nitro group or a halogen atom, and m is 1 Or 2 is represented, n is an integer of 1 to 3, and n + m is 4 or less)

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The spirobiindanephenol sulfonate represented by the general formula (1) of the present invention is a novel compound. In the spirobiindane phenol sulfonic acid ester represented by the general formula (1), R ¹ is an optionally substituted alkyl group or an optionally substituted aryl group. Alkanesulfonic acid esters such as acid ester and ethanesulfonic acid ester, perfluoroalkanesulfonic acid esters such as trifluoromethanesulfonic acid ester and pentafluoroethanesulfonic acid ester,
Examples thereof include aromatic sulfonic acid esters such as benzenesulfonic acid ester and p-toluenesulfonic acid ester.

In the spirobiindanephenol derivative represented by the general formula (1), R ² represents a hydrogen atom, an alkyl group, an alkoxy group, a nitro group or a halogen atom, preferably a hydrogen atom and a carbon number of 1 to 20. Represents an alkyl group, an alkoxy group having 1 to 20 carbon atoms, a nitro group or a halogen atom. More preferably, R ² is a hydrogen atom,
It is an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a chlorine atom, and more preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, isobutyl. Group, tert-butyl group, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, t
It is an ert-butoxy group or a chlorine atom. Particularly preferably, R ² is a hydrogen atom. Moreover, in the spirobiindane phenol sulfonate represented by the general formula (1), m is 1 or 2, n is an integer of 1 to 3, and n + m is an integer of 4 or less. In particular, m is preferably 1, and n is more preferably 1 or 2.

The spirobiindanephenolsulfonic acid ester represented by the general formula (1) of the present invention is a compound in which the hydroxyl group of the spirobiindanephenol skeleton is sulfonated and contains two or more esters. Is. Preferably, the number of esters is two, and specifically, spirobiindane containing two hydroxyl groups represented by the following general formulas (1-a) to (1-d) (Chemical Formula 3). It is a sulfonic acid ester derived from phenol. More preferably, it is a sulfonic acid ester of spirobiindanephenol represented by general formula (1-b) or general formula (1-c), and particularly spirobiindanephenol represented by general formula (1-c). The sulfonic acid ester of is particularly preferable.

[0015]

Embedded image (In the above formula, R ¹ , R ² and n are the same as above)

Specific preferred examples of the spirobiindanephenol sulfonic acid ester represented by the general formula (1) include sulfonic acid esterification products of spirobiindane phenols shown below. It is not limited to these. Exemplified Compound No. 1. 6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-1,1'-spirobiindane 2. 6,6'-dihydroxy-3,3,3 ', 3', 5,5'-hexamethyl-1,1'-spirobiindane 3. 3. 6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-5,5'-diethyl-1,1'-spirobiindane 4. 6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-7,7'-diisopropyl-1,1'-spirobiindane 5. 6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-5,5'-dimethoxy-1,1'-spirobiindane 6. 6.6'-Dihydroxy-3,3,3 ', 3'-tetramethyl-7,7'-dietoxy-1,1'-spirobiindane 7. 6.6'-Dihydroxy-3,3,3 ', 3'-tetramethyl-5,5'-dichloro-1,1'-spirobiindane 8. 6.6'-Dihydroxy-3,3,3 ', 3', 4,4'-hexamethyl-1,1'-spirobiindane 9. 6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-7,7'-di-n-propyl-1,1'-spirobiindane 10.6,6'-dihydroxy-3,3,3 3 ', 3'-tetramethyl-4,4'-di-tert-butyl-1,1'-spirobiindane

11.6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-4,4'-dimethoxy-1,1'-spirobiindane 12.6,6'-dihydroxy-3, 3,3 ', 3'-Tetramethyl-5,5'-dietoxy-1,1'-spirobiindane 13.6,6'-dihydroxy-3,3,3', 3'-tetramethyl-5,5 '-Di-n-propoxy-1,1'-spirobiindane 14.6,6'-dihydroxy-3,3,3', 3'-tetramethyl-4,4'-dichloro-1,1'-spirobiindane 15.6,6'-dihydroxy-3,3,3 ', 3', 7,7'-hexamethyl-1,1'-spirobiindane 16.6,6'-dihydroxy-3,3,3 ', 3' -Tetramethyl-7,7'-di-n-butoxy-1,1'-spirobiidan 17.6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl- 5,5'-di-n-propyl-1,1'-spirobiindane 18.6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-7,7'-di-n-butyl- 1,1'-spirobiindane 19.6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-5,5'-diisopropoxy-1,1'-spirobiindane 20.6,6'-dihydroxy -3,3,3 ', 3'-Tetramethyl-7,7'-diethyl-1,1'-spirobiindane

21.6,6′-Dihydroxy-3,3,3 ′, 3′-tetramethyl-5,5′-diisobutyl-1,1′-spirobiindane 22.6,6′-dihydroxy-3, 3,3 ', 3'-Tetramethyl-4,4'-dietoxy-1,1'-spirobiindane 23.6,6'-dihydroxy-3,3,3', 3'-tetramethyl-7,7 '-Di-n-butoxy-1,1'-spirobiindane 24.6,6'-dihydroxy-3,3,3', 3'-tetramethyl-1,1'-spirobiindane 25.6,6'- Dihydroxy-3,3,3 ', 3', 5,5'-hexamethyl-1,1'-spirobiindane 26.6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-5,5 '-Di-tert-butyl-1,1'-spirobiindane 27.6,6'-dihydroxy-3,3,3', 3'-tetramethyl-7,7'-dime Toxy-1,1'-spirobiindane 28.6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-7,7'-dichloro-1,1'-spirobiindane 29.6,6 '-Dihydroxy-3,3,3', 3'-tetramethyl-1,1'-spirobiindane 30.6,6'-dihydroxy-3,3,3 ', 3', 5,5'-hexamethyl- 1,1'-spirobiindane

31.6,6′-Dihydroxy-3,3,3 ′, 3′-tetramethyl-5,5′-diisopropyl-1,1′-spirobiindane 32.5,5 ′, 6,6 ′ -Tetrahydroxy-3,3,3 ', 3'-tetramethyl-1,1'-spirobiindane 33.4,4', 6,6'-tetrahydroxy-3,3,3 ', 3'-tetramethyl -1,1'-spirobiindane 34.6,6 ', 7,7'-tetrahydroxy-3,3,3', 3'-tetramethyl-1,1'-spirobiindane

The spirobiindane biphenol ester represented by the general formula (1) is synthesized according to a known method for producing a sulfonic acid ester. For example, it can be obtained by subjecting the spirobiindane phenols and the corresponding sulfonic acid chlorides to a dehydrochlorination reaction. At this time, as a hydrochloric acid scavenger, a base, particularly triethylamine,
It is preferably carried out in the presence of organic bases such as triethylamine and pyridine. The amount used may be equivalent to or more than the generated hydrochloric acid, but a small excess, specifically 1 to 2 equivalents, more preferably 1.1 to 1 due to volumetric efficiency during the reaction and complexity of post-treatment. Used in the range of 1.5 equivalents.

At this time, the reaction between the sulfonic acid chlorides and the spirobiindanephenols is generally an exothermic reaction, so it is desirable to proceed with the reaction while dropping any of them. It is generally preferable to add spirobiindane phenols dropwise, but it is not particularly specified. The amount of sulfonic acid chloride used in the reaction is 1 equivalent or less with respect to spirobiindanephenol,
Preferably 1.1 to 3 equivalents, more preferably 1.1 to
Used in the range of 1.5 equivalents. At this time, it is desirable to use a solvent that does not participate in the reaction in order to make the reaction system uniform and facilitate the dropping of the spirobiindane phenols or sulfonic acid chloride. Specific examples thereof include halogen solvents such as dichloromethane, dichloroethane and chloroform, aromatic solvents such as benzene, toluene and chlorobenzene, and ketone solvents such as acetone and methyl ethyl ketone. Of course, an organic base such as triethylamine or pyridine may be used as the solvent.

The reaction temperature is preferably -10 ° C to the boiling point of the reaction solvent, more preferably 0 ° C to the boiling point of the reaction solvent, and most preferably 5 ° C to 50 ° C. The reaction time depends on the reaction temperature, but it is substantially until the starting spirobiindanephenols are not detected, and the reaction is generally completed in about 10 minutes to 10 hours. After completion of the reaction, it is necessary to sufficiently wash the produced hydrochloride salt of the organic amine, a small excess amount of the organic base, sulfonic acid chloride and the like with dilute hydrochloric acid water and neutral water. By the above, spirobiindane phenols can be converted into corresponding sulfonic acid ester.

The spirobiindane phenolsulfonic acid ester produced by this reaction can be obtained in sufficiently high purity. However, purification to a higher degree of purity is preferable for using the spirobiindanephenol sulfonate as the resist material of the present invention. The spirobiindane phenol sulfonate can be further purified by a known method (eg, column chromatography, recrystallization, solvent sludge). It was revealed that the spirobiindanephenol sulfonate represented by the general formula (1) thus obtained has excellent performance as an acid generator for a positive photoresist material.

The positive photoresist material of the present invention contains an alkali-soluble resin, a dissolution inhibitor and an acid generator, and can be developed with an aqueous alkali solution after irradiation.
In positive resist materials sensitive to high energy,
A positive resist material containing spirobiindanephenol sulfonate represented by the general formula (1) as the acid generator, and various known formulations for producing known resist materials as described below It can be given further.

The alkali-soluble resin has a small absorption in the vicinity of the exposure wavelength, that is, in the vicinity of 248 nm of KrF excimer laser to 365 nm of the i-line, preferably even in a single wavelength region, and is not specified as long as it is alkali-soluble. , Preferably a poly (hydroxystyrene) derivative. Preferred poly (hydroxystyrene) derivatives are poly (hydroxystyrene) resins, hydrogenated (polyhydroxystyrene) resins, poly (hydroxystyrene) resins in which some of the hydrogen atoms of the hydroxyl groups are replaced with tert-butoxycarbonyl groups, Hydrogenated poly (hydroxystyrene) resin in which some hydrogen atoms of hydroxyl groups are replaced with tert-butoxycarbonyl groups, poly (hydroxystyrene) resin in which some hydrogen atoms of hydroxyl groups are replaced with tetrahydropyranyl groups, Hydrogenated poly (hydroxystyrene) resin in which some hydrogen atoms of the hydroxyl groups have been replaced with tetrahydropyranyl groups, a copolymer of hydroxystyrene and styrene, and some of the hydrogen atoms of the hydroxyl groups have been replaced with tert-butoxycarbonyl groups. A copolymer of hydroxystyrene and styrene Beauty hydrogen atoms of some hydroxyl groups can be exemplified a copolymer consisting of styrene and hydroxystyrene substituted tetrahydropyranyl group. These resins may be used alone or in combination of two or more.

Further, as the alkali-soluble resin for the resist material of the present invention, in addition to the above-mentioned poly (hydroxystyrene) derivative, a novolak type resin, a phenol aralkyl resin, a naphthol aralkyl resin, a phenol and a dicyclopentadiene It is also possible to use an alkali-soluble resin such as a polymer, polymethylmethacrylate and a copolymer of styrene and maleic anhydride together. The content of the alkali-soluble resin in the resist material of the present invention is preferably 45 to 90% by weight, more preferably 60 to 89% by weight. Particularly preferably, the content of the alkali-soluble resin in the present resist material is 72 to 87%.

Hereinafter, as preferred examples of the alkali-soluble resin, a poly (hydroxystyrene) derivative and a poly (hydroxystyrene) derivative in which hydrogen atoms of some hydroxyl groups are tert-butoxycarbonylated will be described in detail. Among the alkali-soluble resins according to the present invention, as a poly (hydroxystyrene) derivative in which hydrogen atoms of some hydroxyl groups are tert-butoxycarbonylated,
The ert-butoxycarbonylation rate is preferably in the range of 10 to 80%, more preferably 20 to 70%. t
If the ert-butoxycarbonylation rate is too high, the solubility in an alkaline aqueous solution decreases. On the other hand, if the tert-butoxycarbonylation rate is too low, the dissolution inhibiting effect is small. Particularly, the tert-butoxycarbonylation rate is 30 to 6
A range of 0% is preferred.

As a method for tert-butoxycarbonylating a hydrogen atom of a hydroxyl group in a poly (hydroxystyrene) derivative, a method generally used in peptide synthesis is generally used, that is, a poly (hydroxystyrene) derivative is prepared in a pyridine solution. It can be easily produced by reacting di-tert-butyl dicarbonate. The weight average molecular weight of the poly (hydroxystyrene) derivative is preferably 10,000 or more in order to produce a resist film having high heat resistance.

Further, in order to form a highly precise pattern, the molecular weight distribution of the resin is preferably monodisperse. For this reason, it is preferable to use a monodisperse poly (hydroxystyrene) derivative as obtained by living polymerization. Incidentally, the monodispersity means that the molecular weight distribution is Mw / Mn = 1.05 to 1.50. Here, Mw represents the weight average molecular weight of the resin, and Mn represents the number average molecular weight. In the case of living polymerization, the weight average molecular weight can be determined from the weight of the monomer and the number of moles of the initiator, or the light scattering method. on the other hand,
The number average molecular weight can be measured using a membrane osmometer. As a method for obtaining a monodisperse resin, (a) a method of fractionating a resin having a wide molecular weight distribution produced by a radical polymerization method, and (b) a method of obtaining a monodisperse resin from the beginning by a living polymerization method Is mentioned. Of these, it is preferable to use a living polymerization method that does not require a separation treatment. The production of a monodisperse poly (hydroxystyrene) derivative by the living polymerization method and the tert-butoxycarbonylation of the derivative are carried out by, for example,
It can be carried out according to the method described in JP-A-6-287163.

As the dissolution inhibitor in the present invention, publicly known general ones can be used, and examples thereof include those having a benzene ring substituted with a t-butoxycarbonyloxy group. To give a concrete example, the hydroxyl group is t-
Butylcarbonylated various phenol compounds, and as the phenol compounds, hydroquinone, pyrogallol, phloroglysin, 4,4'-dihydroxydiphenylmethane, 2,2'-dihydroxy-5,5'-diphenylmethane, 4,4'- Dihydroxydiphenylpropane, 4,4'-dihydroxydiphenylhexafluoropropane, 4,4'-dihydroxy-3,3'-dimethyl-diphenylpropane, 4,4'-dihydroxydiphenylpropane, and sulfonate esterification raw material in the present invention Examples include spirobiindanephenol and the like. The content of the dissolution inhibitor in the resist material of the present invention is preferably 7 to 40% by weight, more preferably 10% by weight.
３０30% by weight. If the content of the dissolution inhibitor in the resist material is too large, the mechanical strength and heat resistance of the resist film are reduced. Further, if the content is too small, the dissolution inhibiting effect is small. Particularly preferably, the content of the dissolution inhibitor in the resist material is 10 to 20% by weight.

The acid generator contained in the resist material of the present invention is spirobiindanephenol sulfonate represented by the general formula (1) of the present invention. The content of the acid generator is preferably 0.5 to 15% by weight,
More preferably, it is 0.3 to 10% by weight. If the content is too small, the sensitivity of the resist material cannot be improved, and if the content is too large, the mechanical strength of the resist film decreases and the cost of the resist material increases. Particularly preferably, the content of the acid generator is 0.3 to 8
% By weight.

In the resist composition of the present invention, it is preferable to include a sensitizer in a range that does not impair the effects of the present invention, if desired. Examples of the sensitizer include 1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxyphenyl).
Mention may be made of ethyl] benzene, mercaptooxazole, mercaptobenzoxazole, mercaptobenzothiazole, benzoxazolinone, benzothiazolone, mercaptobenzimidazole, urazole, thiouracil, mercaptopyrimidine, imidazolone and their derivatives. At this time, the content of the sensitizer is preferably 40% by weight or less, and more preferably 20% by weight or less with respect to the acid generator. The resist material of the present invention may further contain compatible additives, for example, an additional resin, a plasticizer, a stabilizer or a developed image for improving the performance of the resist film to make the developed image more visible. A commonly used compound such as a coloring agent can be added.

The formation of a positive pattern on a substrate using the resist material of the present invention can be easily carried out by a known method (for example, JP-A-6-287163).
That is, (1) after applying a resist material solution on a substrate, pre-baking is performed to obtain a coated substrate, (2) the obtained coated substrate is irradiated with high energy rays through a photomask, The acid generated by decomposing the acid generator of (3) is subjected to heat treatment, and the acid generated by decomposing the spirobiindanephenolsulfonic acid ester of the formula (1) of the present invention by exposure and heating is dissolved. A substrate having a latent image formed by decomposing the protective group of the inhibitor and eliminating the dissolution inhibiting effect of the resist is obtained (4)
In this method, the substrate having the latent image is developed with an alkaline aqueous solution and washed with water to form a positive pattern.

The resist material solution is the positive photoresist material of the present invention dissolved in an organic solvent, and is usually 1 to 50% by weight, preferably 5 to 35% by weight.
Used as the concentration of. As the organic solvent used, acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl isoamyl ketone, ketones such as cyclohexanone, ethylene glycol, diethylene glycol,
Ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol, dipropylene glycol, propylene glycol monoacetate, dipropylene glycol monoacetate, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monopropyl ether , Polyhydric alcohols such as dipropylene glycol monobutyl ether and derivatives thereof, cyclic ethers such as tetrahydrofuran and dioxane, methyl lactate, ethyl lactate,
Methyl acetate, ethyl acetate, ethoxyethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, esters such as ethyl ethoxypropionate, and mixtures thereof, and the like,
It is not limited to these.

[0035]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Example 1 38.9 g of benzenesulfonyl chloride was placed in a reactor equipped with a stirrer, a thermometer, a dropping funnel, and a condenser.
(0.22 mol) and 250 g of toluene were charged and stirred to obtain a uniform solution. At 25 ° C with continuous stirring,
3,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-1,1'-spirobiindane 30.4 g (0.1 mo
l), pyridine 20 g (0.25 mol), toluene 3
A homogeneous solution consisting of 0 g was added to the stirred solution in 2
It was dropped over time. The internal temperature during dropping was such that the temperature did not exceed 30 ° C. After completion of the dropping, stirring was continued for another 3 hours to allow the reaction to proceed sufficiently, and the raw material 6,6'-dihydroxy-3,3,3 ', 3'-tetramethyl-1,1'-spiro was analyzed by high performance liquid chromatography. It was confirmed that the biindane biphenol disappeared. During the reaction, crystals of pyridine hydrochloride were precipitated, but with the remaining traces of pyridine and benzenesulfonyl chloride, 200 ml of dilute hydrochloric acid was added twice after the reaction, and washing with neutral water was repeated until the drainage became neutral, Completely removed from the organic layer. Then, the solvent was distilled off by a rotary evaporator to obtain 40.7 g (purity 99.3%, yield 99%) of a target sulfonic acid ester as white crystals.

Example 2 A reactor equipped with a stirrer, a thermometer, a dropping funnel and a condenser was charged with p-toluenesulfonyl chloride 41.
9 g (0.22 mol), 6,6'-dihydroxy-3,
3,3 ', 3'-tetramethyl-1,1'-spirobiindane 30.4 g (0.1 mol), pyridine 20 g (0.2
5 mol) and 250 g of toluene are charged, and the internal temperature is 30 ° C.
The reaction was carried out by stirring so as not to exceed the limit. After stirring for 3 hours to allow the reaction to proceed sufficiently, high-performance liquid chromatography was used to determine the starting material 6,6'-dihydroxy-3,3,3 ',
It was confirmed that 3'-tetramethyl-1,1'-spirobiindane had disappeared. During the reaction, crystals of pyridine hydrochloride were deposited, but with the remaining trace amount of pyridine and benzenesulfonyl chloride, after the reaction was completed, the washing was repeated twice with 200 ml of dilute hydrochloric acid and then with neutral water until the drainage became neutral. , Completely removed from the organic layer. After that, the solvent was distilled off with a rotary evaporator, and 42.1 g (purity 9
9.4%, yield 99%) was obtained.

Example 3 A corresponding sulfonate ester was obtained in the same manner as in Example 1, except that benzenesulfonyl chloride was replaced with methanesulfonyl chloride. Example 4 A corresponding sulfonate ester was obtained in the same manner as in Example 1, except that benzenesulfonyl chloride was replaced with trifluoromethanesulfonyl chloride. Example 5 Instead of 6,6′-dihydroxy-3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindambiphenol of Example 1, 6,6′-dihydroxy-3,3 was used. , 3 ', 3', 5,
A corresponding sulfonate ester was obtained in the same manner except that 5'-hexamethyl-1,1'-spirobiindane was used.

Example 6 In place of 6,6′-dihydroxy-3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindane of Example 1, 6,6′-dihydroxy-3,3,3′-tetramethyl-1,1′-spirobiindane was used.
6'-dihydroxy-3,3,3 ', 3'-tetramethyl-
A corresponding sulfonate ester was obtained in the same manner except that 7,7'-diisopropyl-1,1'-spirobiindane biphenol was used. Example 7 6,6′-dihydroxy-3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindane in Example 1 was replaced by 6,
6'-dihydroxy-3,3,3 ', 3',-tetramethyl-
A corresponding sulfonate ester was obtained in the same manner except that 5,5′-dimethoxy-1,1′-spirobiindane was used and 4-phenoxybenzenesulfonyl chloride was used instead of benzenesulfonyl chloride.

Example 8 6,6′-dihydroxy-3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindane of Example 1 was replaced with 6,
6'-dihydroxy-3,3,3 ', 3'-tetomethyl-4,
A corresponding sulfonate ester was obtained in the same manner except that 4′-dichloro-1,1′-spirobiindane was used and isopropylsulfonyl chloride was used instead of benzenesulfonyl chloride. Example 9 Instead of the benzenesulfonyl chloride of Example 1, 1
The corresponding sulphonic acid ester was obtained in a similar manner except that naphthyl sulfonyl chloride was used.

Example 10 A corresponding sulfonate ester was obtained in the same manner except that biphenylsulfonyl chloride was used instead of benzenesulfonyl chloride of Example 1. Example 11 In place of 6,6′-dihydroxy-3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindane of Example 1, 5,
Other than using 5 ', 6,6'-tetrahydroxy-3,3,3', 3'-tetramethyl-1,1'-spirobiindane,
Similarly, the corresponding sulfonate ester was obtained. Example 12 In place of 6,6′-dihydroxy-3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindane of Example 1, 5,
5 ′, 6,6′-tetrahydroxy-3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindane was used, and ethoxymethylsulfonyl chloride was used instead of benzenesulfonyl chloride. Similarly, the corresponding sulfonate ester was obtained. Example 13 In place of 6,6′-dihydroxy-3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindane of Example 1, 4,
4 ', 6,6'-Tetrahydroxy-3,3,3', 3'-tetramethyl-1,1'-spirobiindane was used, and toluyloxymethylsulfonyl chloride was used instead of benzenesulfonyl chloride. The corresponding sulfonic acid ester was obtained in the same manner. Example 14 A corresponding sulfonic acid ester was obtained in the same manner except that cyclohexyloxybenzenesulfonyl chloride was used in place of the benzenesulfonyl chloride of Example 1.

Examples 15 to 22 Using the base resins, dissolution inhibitors and acid generators shown in Table 1 (Table 1), resist coated substrates were manufactured by the following methods and evaluated by the following methods. , The results are shown in Table 2 (Table 2)
It was shown to. In addition, Mw in Table 1 represents the molecular weight of the base resin. [Manufacturing Method of Resist Coated Substrate] A resist solution prepared by mixing the following compositions was 2,000 rpm on a silicone substrate.
Spin coating for 1 minute and prebaking on a hot plate at 85 ° C. for 1 minute to manufacture a resist coated substrate having a resist film thickness of 0.7 μm. Base resin 81 parts by weight Dissolution inhibitor 14 parts by weight Acid generator (compound of Example 1 or 2) 5 parts by weight Coating solvent (ethoxyethyl acetate) 400 parts by weight Total 500 parts by weight

[Evaluation Method of Resist Coated Substrate] The characteristics of the resist material of the present invention were measured by the following methods using the resist coated substrate manufactured by the above-mentioned method. (1) Sensitivity: reduction exposure projection device N on each resist coated substrate
After exposure using SR-1505EX (manufactured by Nikon Corporation) at an excess interval of 10 mJ from 10 mJ, 100
After heating for 90 seconds at 90 ° C., then immersion development with a 2.4% by weight tetramethylammonium hydroxide aqueous solution for 65 seconds, washing for 30 seconds with water, and drying, the sensitivity is determined as appropriate exposure time (minimum exposure time required for patterning. ) Was measured. The results are expressed as values in units of 10 mJ, and the smaller the value, the shorter the exposure time and the better the sensitivity. (2) Cross-sectional shape (a) Immediately after exposure development processing: A silicon wafer obtained by exposing each resist-coated substrate with a reduction exposure projection device NSR-1505EX (manufactured by Nikon Corporation) for an optimum exposure time was heated to 100 ° C. After heating for 90 seconds, dipping and developing with a 2.4 wt% tetramethylammonium hydroxide aqueous solution for 65 seconds, washing with water for 30 seconds, and drying, the cross-sectional shape of the resist pattern is observed under a microscope, and the side surface is vertical. "○" means that the side surface is not vertical, and "x" means that the side surface is overhanging or strongly tapered. (B) 1-hour post-exposure development treatment: A silicon wafer obtained by exposing each resist-coated substrate to the optimum exposure time using a reduction exposure projection device NSR-1505EX (manufactured by Nikon Corporation) at 100 ° C. for 90 seconds. After heating, it was allowed to stand at room temperature for 1 hour, then immersion developed with a 2.4 wt% tetramethylammonium hydroxide aqueous solution for 65 seconds, washed with water for 30 seconds, and dried to obtain a cross-sectional shape of a resist pattern with a microscope. Observed, the one with vertical side faces was marked with "O", and the one with non-vertical side faces and overhang or strong taper was marked with "X".

Comparative Example 1 A resist was prepared in the same manner as in Example 15 except that tri-tert-butoxycarbonylpyrogallol was used as the acid generator in Example 15 instead of the compound in Example 1. A coated substrate was obtained, evaluated by the above method, and shown in Table 2. Comparative Example 2 Resist coating was performed in the same manner as in Example 15 except that di-tert-butoxycarbonylbisphenol A was used as the acid generator in Example 15 instead of the compound in Example 1. Substrates were obtained, evaluated by the methods described above, and shown in Table 2.

[0044]

[Table 1] tBC-HS: tert-butoxycarbonylated poly (p-hydroxystyrene) THP-HS: tetrahydropyranylated poly (p-hydroxystyrene) XL: phenol aralkyl resin HS: polyhydroxystyrene T-tBC-PG: tri-t -Butoxycarbonylpyrogallol D-tBC-BA: Di-t-butoxycarbonylbisphenol A D-tBC-HFBA: Di-t-butoxycarbonylhexafluorobisphenol A

[0045]

[Table 2] As is clear from Table 2, the resist material using the spirobiindanephenolsulfonic acid ester represented by the general formula (1) of the present invention as an acid generator is prepared by using a conventionally used acid generator. Compared with the produced resist material, it has excellent sensitivity and resolution and high stability over time.

[0046]

According to the present invention, it is possible to provide a positive resist material for high energy rays which is excellent in sensitivity and resolution.

Claims (4)

[Claims] 1. A spirobiindanephenol sulfonate represented by the following general formula (1) (formula 1). Embedded image (In the formula, R ¹ represents an optionally substituted alkyl group or an optionally substituted aryl group, R ² represents a hydrogen atom, an alkyl group, an alkoxy group, a nitro group or a halogen atom, and m is 1 Or 2 is represented, n is an integer of 1 to 3, and n + m is 4 or less) 2. A positive photoresist material comprising an alkali-soluble resin, a dissolution inhibitor and an acid generator,
A positive photoresist material comprising the spirobiindanephenol sulfonate according to claim 1 as an acid generator. 3. The positive photoresist material according to claim 2, wherein the alkali-soluble resin contains polyhydroxystyrene or a derivative thereof. 4. The positive photoresist material according to claim 3, wherein the alkali-soluble resin contains a phenol aralkyl resin or a derivative thereof.