JP2016018168A - Photosensitive resin composition and use of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition having high resolution, no development residue and good sensitivity while maintaining a high ratio of a developed residual film.SOLUTION: The photosensitive resin composition comprises: a novolac resin as a component (A); an esterified product having a quinonediazide group as a component (B); and as a component (C), an indene copolymer having a specific structure containing a structural unit derived from indene, a structural unit derived from an acid anhydride monomer, and a structural unit derived by esterifying an acid anhydride monomer with alcohol.SELECTED DRAWING: None

Description

  The present invention relates to a positive photosensitive resin composition having photosensitivity and its use. Specifically, the present invention relates to a photosensitive resin composition capable of forming a pattern film by using a photolithography technique, and further to a flat panel display (FPD) or a semiconductor device manufactured using the same.

  Conventionally, photolithography technology has been used to form or process microelements in a wide range of fields including semiconductor integrated circuits such as LSIs, FPD display surfaces, thermal heads and other circuit boards. It's being used. In the photolithography technique, a photosensitive resin composition is used to form a resist pattern. In recent years, in the manufacture of semiconductor elements typified by TFTs and the like, high definition has progressed, and the width of wirings and the width between wirings have become narrower. For this reason, a photosensitive resin composition with higher resolution is strongly desired.

  As a high-resolution material, a composition in which a novolac resin and a naphthoquinonediazide group-containing photosensitive agent are combined is widely known. In order to increase the resolution with this composition, it is necessary to suppress pattern sagging during the firing step, and as a countermeasure to this, heat resistance is usually improved by adjusting the molecular weight of the novolak resin to be high. However, when the molecular weight of the novolak resin is increased, the sensitivity is lowered, and this method has a limit in terms of both resolution and sensitivity. Many studies have been made on photosensitive resin compositions used for such applications.

  For example, Patent Document 1 discloses a photosensitive resin composition in which a cyclic olefin resin is added in addition to a novolak resin and a naphthoquinonediazide group-containing photosensitive agent in order to improve heat resistance. However, although the addition of the cyclic olefin resin can achieve an improvement in resolution due to an increase in heat resistance, it takes 90 seconds for development to achieve the sensitivity required in the manufacturing process. This is a problem.

  In order to solve such problems, the photosensitive resin composition used in the manufacture of FPDs and semiconductor devices has high resolution, maintains a high residual film rate, has no development residue, and has good sensitivity. Photosensitive resin is required.

International Publication No. 2012/026465

The present invention has been made in view of the above circumstances, and the object thereof is to provide a high resolution and high residual film by using an indene copolymer having a specific structure in addition to a novolak resin and an esterified product having a quinonediazide group. An object of the present invention is to provide a photosensitive resin composition having no development residue and good sensitivity while maintaining the rate.
The second object of the present invention is to provide an FPD or a semiconductor device produced by using the excellent photosensitive resin composition.

  As a result of intensive research under these backgrounds, the present inventors have found that a novolak resin as component (A), an esterified product having a quinonediazide group as component (B), and an indene having a specific structure as component (C). By using the copolymer at a compounding ratio of 5 to 50 parts by mass of the component (B) and 5 to 50 parts by mass of the component (C) with respect to 100 parts by mass of the component (A), the above-mentioned problem is achieved. The inventors have found that this can be solved, and have completed the present invention.

（式中、Ｒ^１は水素原子又はメチル基）

（式中、Ｒ^１は水素原子又はメチル基、Ｒ^２、Ｒ^３はそれぞれ独立して水素原子又は炭素数１〜４のアルキル基、ベンジル基、シクロアルキル基であり、少なくともいずれか一方は水素原子） That is, this invention contains a component (A), a component (B), and a component (C), and the component ratio of each component is 5-50 mass parts of components (B) with respect to 100 mass parts of components (A), A photosensitive resin composition that is 5 to 50 parts by mass of component (C),
Component (A) is a novolak resin, Component (B) is an esterified product having a quinonediazide group obtained by esterifying a polyfunctional phenolic compound and a quinonediazide compound, and component (C) is represented by the following formula ( (C1) a structural unit derived from indene represented by 1) to (3), (c2) a structural unit derived from an acid anhydride monomer, and (c3) an acid anhydride monomer (c2) As a percentage of the molar ratio (c3) / (c2) between the number of moles of the structural unit (c3) and the number of moles of the structural unit (c2) before esterification. It is related with the photosensitive resin composition characterized by being an indene copolymer whose certain esterification rate is 40% or more.

(Wherein R ¹ is a hydrogen atom or a methyl group)

(In the formula, R ¹ is a hydrogen atom or a methyl group, R ² and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a benzyl group or a cycloalkyl group, at least one of which is hydrogen. atom)

  Furthermore, the present invention provides the photosensitive resin, wherein the cresol skeleton of the novolak resin of the component (A) is composed of m-cresol and p-cresol, and the molar ratio thereof is 80:20 to 20:80. Relates to the composition.

  Further, in the present invention, the novolak resin of the component (A) includes a cresol skeleton and a xylenol skeleton, and the cresol skeleton is selected from at least one of m-cresol and p-cresol, and the xylenol skeleton is 2,3-xylenol. , 2,5-xylenol, 3,4 xylenol, and 3,5 xylenol, the molar ratio of which is cresol: xylenol = 99: 1 to 50:50 About.

  Furthermore, this invention relates to the flat panel display produced using this photosensitive resin composition, and a semiconductor device.

  The photosensitive resin composition of the present invention has a high resolution and maintains a high residual film ratio in a development process for forming a pattern film using a photolithography technique. Can be formed. And the FPD and semiconductor device which have the outstanding characteristic can be provided by using this photosensitive resin composition.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments embodying the present invention will be described in detail.
The photosensitive resin composition of this invention contains the component (A), the component (B), and the component (C) shown below, and the component ratio of each component is a component (with respect to 100 parts by mass of the component (A) ( B) 5 to 50 parts by mass and component (C) 5 to 50 parts by mass are set.
Component (A): Novolak resin Component (B): Esterified product having quinonediazide group Component (C): Indene copolymer having specific structure

  Hereinafter, each component will be described in order.

<Component (A): Novolak resin>
The novolak resin of component (A) is not particularly limited, and a novolak resin used in a known positive photosensitive resin composition, for example, an aromatic hydroxy compound such as phenol, cresol or xylenol and an aldehyde such as formaldehyde with hydrochloric acid. , Oxalic acid, formic acid, paratoluenesulfonic acid and the like condensed in the presence of an acidic catalyst can be used.
From the viewpoint of sensitivity, it is preferable to synthesize from m-cresol and p-cresol, and the molar ratio of m-cresol and p-cresol is preferably in the range of 20:80 to 80:20. When the molar ratio of m-cresol in this novolak resin is less than 20, the sensitivity is lowered, and when it exceeds 80, the remaining film ratio is lowered.
To further increase the sensitivity, at least one selected from m-cresol and p-cresol and at least one selected from 2,3-xylenol, 2,5-xylenol, 3,4 xylenol, and 3,5 xylenol is selected. The molar ratio is preferably cresol: xylenol = 99: 1 to 50:50. When the molar ratio of xylenol in the novolak resin exceeds 50, the remaining film ratio decreases.
These novolak resins have a mass average molecular weight of 2,000 to 20,000, preferably 3,000 to 15,000 in terms of sensitivity and resolution.

<Component (B): Esterified product having a quinonediazide group>
When the ester compound having a quinonediazide group as component (B) is exposed through a photomask in an exposure process by photolithography, a photoisomerization reaction of an esterified product having a quinonediazide group occurs in the exposed portion to generate a carboxyl group. In the subsequent development step, it can be dissolved in the developer. On the other hand, since the unexposed part has a dissolution inhibiting ability with respect to the developer, a film can be formed. That is, since the component (B) can be exposed through a photomask to exhibit a difference in solubility in a developer in the subsequent development process, a pattern film can be obtained.
The esterified product having a quinonediazide group as component (B) can be obtained by esterifying a quinonediazide compound and a phenolic compound. Examples of the quinonediazide compound include 1,2-naphthoquinonediazide-5-sulfonyl chloride, benzoquinonediazide represented by naphthoquinonediazidesulfonic acid halide represented by 1,2-naphthoquinonediazide-4-sulfonylchloride, and benzoquinonediazidesulfonic acid chloride. Sulfonic acid halides are used. As the phenolic compound, compounds represented by the following formulas (4), (5) and (6) are preferable.

The esterification rate of the esterified product having a quinonediazide group as component (B) is 20 to 100%, and preferably 50 to 95% from the viewpoint of sensitivity. However, the esterification rate is represented by the following formula (I).
Esterification rate (%) = (Z / number of OH in phenolic compound) × 100 (I)
(Z represents 4 × (area ratio of 4 mol isomer) + 3 × (area ratio of 3 mol isomer) + 2 × (area ratio of 2 mol isomer) + 1 × (area ratio of 1 mol isomer), and the area ratio is high performance liquid chromatography. Can be evaluated from the results of
When the esterification rate is less than 20 mol%, the sensitivity is lowered.
The composition ratio of the esterified product of component (B) in the photosensitive resin composition is 5 to 50 parts by mass with respect to 100 parts by mass of novolak resin of component (A), and preferably 15 to 35 from the aspects of sensitivity and developability. Part by mass. When this proportion is less than 5 parts by mass, the sensitivity is lowered, and when it exceeds 50 parts by mass, the developability is lowered.

<Component (C): Indene copolymer having specific structure>
The indene copolymer having a specific structure as the component (C) is added to form a high-resolution pattern by improving heat resistance and suppressing pattern sagging during post-baking.
Component (C) is an indene copolymer containing structural units (c1), (c2) and (c3), which is a structural unit derived from indene, and (c1), an acid anhydride monomer (C2) which is a structural unit derived from is obtained as an indene copolymerization intermediate, and then the site derived from the acid anhydride monomer (c2) in the indene copolymerization intermediate is obtained with alcohol. The indene copolymer (C) can be obtained by inducing the structural unit (c3) by esterification.

An indene monomer can be used as the structural unit (c1) derived from indene in the indene copolymer (C) having a specific structure. Since the indene copolymer (C) containing the structural unit (c1) derived from indene has a rigid main chain structure, it has a high glass transition point, suppresses sagging during high-temperature baking, and has a high resolution pattern. Can be formed. Further, the structural unit (c2) derived from the acid anhydride monomer can be easily copolymerized with the structural unit (c1) derived from indene, and is derived from the acid anhydride monomer (c2). The structural unit (c3) can be derived by esterifying the above site with an alcohol to impart alkali developability. As the structural unit (c2) derived from an acid anhydride monomer, R ¹ in the above formula (2) is a hydrogen atom or a methyl group, specifically a maleic anhydride or a citraconic anhydride monomer Can be used.

  When synthesizing the indene copolymerization intermediate obtained by copolymerizing the structural unit (c1) and the structural unit (c2), the synthesis method is not particularly limited, but a known radical polymerization method is used. Can be applied. In that case, the monomer which forms the structural units (c1) and (c2), which are copolymerization components, can be charged all at once into the polymerization kettle, or can be divided and dropped into the reaction system.

  As a polymerization solvent used for obtaining an indene copolymerization intermediate, a solvent generally used for radical polymerization can be used. Specific examples of such solvents include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate. Diethylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether and diethylene glycol methyl ethyl ether, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol mono Propylene glycol monoalkyl ether acetates such as tilether acetate, lactic acid esters such as methyl lactate and ethyl lactate, aromatic hydrocarbons such as toluene and xylene, ketones such as methyl ethyl ketone, methyl isobutyl ketone, 2-heptanone and cyclohexanone Amides such as N, N-dimethylacetamide and N-methylpyrrolidone, and lactones such as γ-butyrolactone. These polymerization solvents can be used alone or in admixture of two or more. Among the solvents for polymerization, methyl ethyl ketone, methyl isobutyl ketone, and propylene glycol monomethyl ether acetate are preferable.

  As a polymerization initiator used for obtaining an indene copolymerization intermediate, a radical polymerization initiator generally used in a radical polymerization method can be used. Specific examples thereof include an azo polymerization initiator, an azo polymerization initiator having no cyano group, an organic peroxide, and hydrogen peroxide. When a peroxide is used as the radical polymerization initiator, it may be used as a redox polymerization initiator in combination with a reducing agent.

  In order to adjust the weight average molecular weight in obtaining the indene copolymerization intermediate, a molecular weight modifier can be used. Examples of the molecular weight regulator include mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan, thioglycolic acid and mercaptopropionic acid, and xanthogens such as dimethylxanthogen disulfide and diisopropylxanthogen disulfide. , Terpinolene, α-methylstyrene dimer, and the like.

The structural unit (c3) derived by esterifying the site derived from the acid anhydride monomer (c2) in the indene copolymer intermediate with an alcohol is a component that contributes to developability in the development step. In Formula (3), R ¹ is a hydrogen atom or a methyl group, R ² and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a benzyl group, or a cycloalkyl group, and at least one of them. Is a hydrogen atom.
As the alcohol for deriving the structural unit (c3), an aliphatic alcohol having 1 to 4 carbon atoms, cyclohexanol as an alicyclic alcohol, and benzyl alcohol as an aromatic alcohol can be used. These alcohols can be used alone or in admixture of two or more. In the esterification reaction with alcohol, the ratio of the number of moles of the structural unit (c3) after the esterification reaction is divided by the number of moles of the acid anhydride structural unit (c2) before the esterification reaction and expressed as a percentage of esterification. Can do. The esterification rate of the esterification reaction with alcohol is 40% or more. When the esterification rate is less than 40%, developability is lowered.
In the esterification reaction with alcohol, an excessive amount of alcohol can be added to the number of moles of the acid anhydride structural unit (a2) for the purpose of improving the reaction rate. Although there is no restriction | limiting in particular as an excess amount of alcohol, About 1.1-10 times mole is preferable with respect to the number-of-moles of an acid anhydride structural unit (c2).
In the esterification reaction with alcohol, an esterification reaction catalyst can be used for the same purpose. As the esterification reaction catalyst, amine catalysts such as triethylamine, pyridine and dimethylaminopyridine, and acid catalysts such as methanesulfonic acid, p-toluenesulfonic acid, hydrochloric acid and sulfuric acid can be used.

Regarding the composition of the structural units (c1), (c2) and (c3) which are copolymerization components of the indene copolymer (C), from the viewpoint of resolution, (c1) is 40 to 60 mol%, preferably 45 to 45 mol%. From the viewpoint of developability and residual film ratio, the structural unit (c2) is 2 to 36 mol%, preferably 2 to 30 mol% and the structural unit (c3) is 16 to 58 mol%, preferably 20 ~ 53 mol%.
The indene copolymer is preferably 5 to 50 parts by mass with respect to 100 parts by mass of the novolak resin of the component (A), and preferably 10 to 35 parts by mass in terms of resolution and developability.
When this component ratio is less than 5 parts by mass, the resolution is lowered, and when it exceeds 50 parts by mass, the developability is lowered.
The weight average molecular weight of the indene copolymer (C) is preferably 5,000 to 60,000, more preferably 8,000 to 30,000. When the weight average molecular weight is less than 5,000, the heat resistance may be deteriorated. When the weight average molecular weight is more than 60,000, the solubility in the developer is poor and the developability is lowered.

<Other additive components>
In the photosensitive resin composition of the present invention, additives such as a solvent, an adhesion improving aid, and a surfactant can be blended without departing from the object of the present invention.

(solvent)
As the solvent, a known solvent that can be used in the photosensitive resin composition can be used. Specific examples of the solvent include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate, and diethylene glycol dimethyl ether. , Diethylene glycol dialkyl ethers such as diethylene glycol diethyl ether and diethylene glycol methyl ethyl ether, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether Propylene glycol monoalkyl ether acetates such as acetate, lactic esters such as methyl lactate and ethyl lactate, aromatic hydrocarbons such as toluene and xylene, ketones such as methyl ethyl ketone, 2-heptanone and cyclohexanone, N, N-dimethyl Examples include amides such as acetamide and N-methylpyrrolidone, and lactones such as γ-butyrolactone. These solvents can be used alone or in admixture of two or more.

(Adhesion improvement aid and surfactant)
If necessary, the photosensitive resin composition of the present invention may further contain an adhesion improving aid, a surfactant and the like. Examples of the adhesion improving aid include alkyl imidazoline, polyhydroxystyrene, polyvinyl methyl ether, t-butyl novolac, epoxy silane, silane coupling agent and the like. Examples of surfactants include, for example, TSF-431, TSF-433, TSF-437 manufactured by Momentive Performance Materials Japan, <Novec> HFE manufactured by Sumitomo 3M Co., Ltd., Dainippon Ink & Chemicals, Inc. ) Manufactured by MegaFuck F-477, F-483, F-554, TF-1434, TEGO-made Glide-410, Glide-440, Glide-450, Glide-B1484, and the like.

(Contrast improver)
In the photosensitive resin composition of the present invention, a phenolic compound represented by the above formula (6) or the following formulas (7) to (10) can be blended for the purpose of improving contrast. The phenol group of these phenolic compounds causes an azo coupling reaction with the diazo group of the photosensitive agent of component (B) in the unexposed area where no light is irradiated, thereby enhancing the dissolution inhibiting effect of component (B). As a result, compared to the case where these phenolic compounds are not used, the difference in solubility in the alkaline developer between the exposed area and the unexposed area can be increased (contrast increased), so the remaining film ratio and resolution are improved. Can be expected. It is used in an amount of 1 to 20 parts by mass with respect to 100 parts by mass of the component (A) novolac resin.

<Method for preparing photosensitive resin composition>
In preparing the photosensitive resin composition, each component including the component (A), the component (B) and the component (C) may be blended together, or after each component is dissolved in a solvent, You may mix | blend. In addition, there are no particular restrictions on the charging order and working conditions when blending.
For example, the resin composition may be prepared by dissolving all the components in a solvent at the same time, and if necessary, each component is appropriately made into two or more solutions, and these solutions are used at the time of use (at the time of application). You may mix and prepare as a photosensitive resin composition.

<Flat panel display and semiconductor device>
The flat panel display and the semiconductor device of the present invention are produced using the photosensitive resin composition of the present invention. Usually, the photosensitive resin composition is coated on a substrate and prebaked to form the photosensitive resin composition. The coating film is formed. At this time, the substrate to which the photosensitive resin composition is applied may be any known substrate such as a conventional FPD substrate or a semiconductor device forming substrate such as glass or silicon. The substrate may be a bare substrate, may be formed with an oxide film, a nitride film, a metal film, or the like, or may be a substrate on which a circuit pattern or a semiconductor device is formed. Moreover, the temperature of prebaking is 40-140 degreeC normally, and time is about 0-15 minutes. Next, pattern exposure is performed on the coating film through a predetermined mask, and then PEB (post-exposure bake) treatment is performed as necessary, followed by development processing using an alkaline developer, rinsing processing, and photosensitivity. A film of the conductive resin composition is formed. The PEB treatment is usually performed at 100 to 130 ° C. and for 1 to 10 minutes. The film thus formed is post-baked to form a pattern film. Moreover, post-baking temperature is 100-150 degreeC normally, and time is 3 to 15 minutes.
In the formation of the pattern film, as a coating method of the photosensitive resin composition, any method such as a spin coating method, a roll coating method, a land coating method, a spray method, a casting coating method, a dip coating method, and a slit coating method can be used. That's fine. Examples of radiation used for exposure include ultraviolet rays such as g-rays, h-rays, and i-rays, far ultraviolet rays such as KrF excimer laser light or ArF excimer laser light, X-rays, and electron beams.
As a developing method, a method conventionally used for developing a photoresist, such as a paddle developing method, an immersion developing method, a swinging immersion developing method, or a shower type developing method may be used. Developers include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate and sodium silicate, organic amines such as ammonia, ethylamine, propylamine, diethylamine, diethylaminoethanol and triethylamine, and tetramethylammonium hydroxide. An aqueous solution in which a quaternary amine or the like is adjusted to a predetermined concentration can be used.

  Hereinafter, embodiments of the present invention will be described more specifically with reference to examples and comparative examples. “Part” and “%” are all based on mass unless otherwise specified. The measurement methods and evaluation methods used in the examples and comparative examples are shown below.

<Mass average molecular weight>
The mass average molecular weight (Mw) was measured with a RI detector using a gel permeation chromatography apparatus HLC-8220GPC manufactured by Tosoh Corporation, Tskel HZM-M manufactured by Tosoh Corporation as a column, and THF as an eluent. Thus, it was determined by conversion using a calibration curve obtained from a polystyrene standard having a known molecular weight.

1. Synthesis of novolak resin [Synthesis Example 1-1, synthesis of novolak resin A-1]
In a 300 mL four-necked flask equipped with a thermometer, stirrer, heat exchanger, and condenser, 97.3 g of m-cresol, 10.8 g of p-cresol, 56.8 g of 37% formalin, and 0. 6 oxalic acid were added. 54 g was charged and maintained under reflux conditions for 4 hours. Thereafter, dehydration was performed under normal pressure to an internal temperature of 170 ° C., and dehydration / demonomerization was performed up to 200 ° C. under a reduced pressure of 9.5 × 10 ³ Pa to obtain Novolak Resin A-1.

[Synthesis Examples 1-2 to 1-6, synthesis of novolak resins A-2 to A-6]
A novolak resin was synthesized in the same manner as in Synthesis Example 1-1 except that the charged species and amounts described in Table 1 were changed.

[Synthesis Example 2-1, Synthesis of Novolak Resin B-1]
In a 300 mL four-necked flask equipped with a thermometer, stirrer, heat exchanger, and condenser, p-cresol 107.1 g, 2,3 xylenol 1.2 g, 37% formalin 56.8 g, oxalic acid 0 .54 g was charged and maintained under reflux conditions for 4 hours. Thereafter, dehydration was performed under normal pressure to an internal temperature of 170 ° C., and dehydration / demonomerization was performed to 200 ° C. under a reduced pressure of 9.5 × 10 ³ Pa to obtain a novolak resin B-1.

[Synthesis Examples 2-2 to 2-7, synthesis of novolak resins B-2 to B-7]
A novolac resin was synthesized in the same manner as in Synthesis Example 2-1, except that the preparation types and amounts described in Table 2 were changed.

2. Synthesis of indene copolymerization intermediate [Synthesis Example 3-1, synthesis of indene copolymerization intermediate C′-1]
A 500 mL four-necked flask equipped with a thermometer, a stirrer, and a condenser tube was charged with 87.0 g of methyl isobutyl ketone (MIBK), purged with nitrogen, and then heated up to 110 ° C. with an oil bath.
On the other hand, 44.1 g of indene, 55.9 g of maleic anhydride, 5.0 g of peroxide-based polymerization initiator Perbutyl O [manufactured by NOF Corporation] and 58.0 g of MIBK were prepared in advance to prepare a dropping component. And after dripping this dripping component to the said MIBK at a constant speed with a dropping funnel over 1 hour, it maintained at the same temperature for 2 hours, and obtained copolymerization intermediate C'-1.

[Synthesis Examples 3-2 to 3-6, Synthesis of Copolymer Intermediates C′-2 to C′-6]
An indene copolymerization intermediate was synthesized in the same manner as in Synthesis Example 1-1 except that the preparation species and amount shown in Table 3 were changed to the polymerization temperature.

The meanings of the abbreviations in Table 3 are as follows.
AIBN: 2,2′-azobisisobutyronitrile [azo polymerization initiator, manufactured by Wako Pure Chemical Industries, Ltd.]
Perbutyl O: t-butyl peroxy-2-ethylhexanoate (peroxide-based polymerization initiator, manufactured by NOF Corporation)
MEK: methyl ethyl ketone MIBK: methyl isobutyl ketone PGMEA: propylene glycol monomethyl ether acetate

3. Synthesis of indene copolymer [Synthesis Example 4-1, synthesis of indene copolymer C-1]
After 91.3 g of methanol was dropped at a constant rate using a dropping funnel over 250 minutes to 250 g of the indene copolymer intermediate C′-1 solution of Synthesis Example 1-1 adjusted to 80 ° C., the mixture was maintained at the same temperature for 20 hours. An esterified reaction solution was obtained. Thereafter, the reaction solution was reprecipitated with 10 times the amount of normal hexane to obtain an indene copolymer C-1.

[Synthesis Examples 4-2 to 4-12, synthesis of indene copolymers C-2 to C-12]
An indene copolymer was synthesized in the same manner as in Synthesis Example 2-1, except that the preparation type and amount described in Table 4 were changed to the reaction temperature.

<Calculation of composition ratio>
The composition ratio was determined according to ASTM D3644-06 “Standard Test Method for Acid Number of Styrene-Maleic Anhydride Resins”, and the acid ratio of acid anhydride and carboxyl group was determined and the composition ratio after polymerization was determined.

[Comparative Synthesis Examples 1 and 2, Synthesis of Indene Copolymers C-13 to C-14]
A copolymer was synthesized in the same manner as in Synthesis Example 4-1, except that the preparation type and amount described in Table 5 were changed to the reaction temperature.

[Comparative Synthesis Example 3, Synthesis of Copolymer C-15]
A 500 mL four-necked flask equipped with a thermometer, stirrer and condenser is charged with 100.0 g of powdery SMA-1000 and 150.0 g of methyl isobutyl ketone (MIBK), and the liquid temperature is 120 ° C. in an oil bath. The temperature was increased while stirring until SMA-1000 was dissolved, and then 0.2 g of triethylamine was added. Next, 99.1 g of cyclohexanol was dropped at a constant rate with a dropping funnel over 15 minutes, and then maintained at the same temperature for 20 hours to obtain an esterified reaction solution. Thereafter, the reaction solution was reprecipitated with 10 times the amount of normal hexane to obtain a copolymer C-15.

[Comparative Synthesis Example 4, Synthesis of Copolymer C-16]
A copolymer was synthesized in the same manner as in Comparative Synthesis Example 3 except that the preparation type and amount described in Table 5 were changed to the reaction temperature.

The meanings of the abbreviations in Table 5 are as follows.
SMA-1000: Styrene-maleic anhydride copolymer, constituent unit ratio = 50/50 (manufactured by Kawa Crude Co., Ltd.)

[Comparative Synthesis Example 5, Synthesis of Copolymer C-17]
[4- (2-Bicyclo [2.2.1] hept-5-ene) phenyl] acetate (11.4 g), toluene (17.6 g) and methyl ethyl ketone (27.4 g) equipped with a stirrer The inside was replaced with dry nitrogen gas. The contents were heated, and when the internal temperature reached 50 ° C., a solution in which (η ⁶ -toluene) Ni (C ₆ F ₅ ) ₂ (0.97 g,) was dissolved in 10 g of toluene was added. After reacting at 50 ° C. for 3 hours, the mixture was cooled to room temperature. THF (50 g) and 10% aqueous potassium hydroxide solution (80 g) were added, and the mixture was refluxed for 5 hours. Then, after adding and neutralizing acetic acid, the water washing operation | work with ion-exchange water was implemented 3 times. The organic layer was concentrated with an evaporator and then reprecipitated with hexane. The obtained solid was dried in a vacuum dryer at 60 ° C. overnight to obtain 8.2 g of a pale yellow powder. The molecular weight of the obtained polymer was Mw = 11,000 by GPC.

[Example 1-1]
105.0 g of the novolak resin A-1 listed in Table 1, 25.0 g of an esterified product of the compound represented by the formula (4) and 1,2-naphthoquinonediazide-5-sulfonyl chloride, Synthesis Example 4- 20.0 g of the indene copolymer C-5 obtained in No. 5, in order to prevent radial wrinkles formed on the resist film during spin coating, so-called striations, a silicon surfactant, G-B1484 [TEGO] was dissolved in 0.5 g of an appropriate amount of propylene glycol monomethyl ether acetate (PGMEA) and stirred, and then filtered through a 0.2 μm filter to prepare a photosensitive resin composition.

(Formation of thin film pattern)
The photosensitive resin composition was spin-coated on a 6-inch silicon wafer and baked on a hot plate at 100 ° C. for 90 seconds to obtain a thin film (A) having a thickness of about 1.6 μm. This thin film was exposed to various line widths and contact hole test patterns having a line and space width of 1: 1 at an optimum exposure amount using an i-line stepper (FPA-2500i2) manufactured by Canon Inc. Line and space pattern and contact hole pattern with a line and space width of 1: 1 are formed by developing for 60 seconds at 23 ° C with a 2.38 mass% tetramethylammonium hydroxide aqueous solution after PEB treatment on a hot plate for 90 seconds A thin film (B) was obtained. This thin film (B) was post-baked by heating at 150 ° C. for 3 minutes on a hot plate to obtain a patterned thin film (pattern film) having a thickness of about 1.5 μm.

(Evaluation of developability)
Among the patterns prepared above, a 1.5 μm hole pattern was observed with a SEM (scanning electron microscope). The developability was evaluated as x when a residue was found on the entire surface inside the hole, ◯ when a residue was found at the end of the hole, and ◎ when no residue was found on the entire surface inside the hole.
If the residue is on the front surface, the wiring will be defective due to the etching at the time of wiring formation.

(Evaluation of developed film ratio)
From the film thickness of the thin film (A) and the thin film (B) obtained by the above method, the development residual film ratio was calculated from the following formula.
Development residual film ratio (%) = (thickness of thin film (B) (μm) / thickness of thin film (A) (μm)) × 100
Since a reduction in the development residual film ratio causes a reduction in productivity, it is preferably 90% or more, more preferably 95% or more.

(Evaluation of sensitivity)
Line and space width in the above method is 1: exposure amount 1 line and space pattern is obtained (mJ / cm ²⁾ for the sensitivity, what sensitivity is ^{10~15mJ / cm 2 ◎, 15~20mJ /} cm ○ those ^two, things 20~25mJ / cm ² △, was evaluated as × 25mJ / cm ² or more.
From the viewpoint of productivity, Δ is preferable, ○ is more preferable, and ◎ is particularly preferable.

(Resolution evaluation)
Among the patterns prepared above, those that can be resolved up to 1.0 μm line & space after post-baking are ◎, those that can be resolved up to 1.5 μm line & space are ○, 1.5 μm Those that could not resolve the line and space were evaluated as x.
From the viewpoint of high definition, ○ is preferable, and ◎ is more preferable.

[Examples 1-2 to 1-27]
Except for using the novolak resin of component (A) shown in Table 6 to Table 8, the esterified product having a quinonediazide group of component (B), the indene copolymer having a specific structure of component (C), and other additives. A photosensitive resin composition was prepared by performing the same operation as in Example 1-1. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

<Examples 2-1 to 2-28>
Other than using the novolak resin of component (A) shown in Table 9 to Table 11, the esterified product having a quinonediazide group of component (B), the indene copolymer having a specific structure of component (C), and other additives. A photosensitive resin composition was prepared by performing the same operation as in Example 1-1. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

[Comparative Examples 1-1 to 1-10]
The same operation as in Example 1-1 is performed except that the novolak resin of component (A) shown in Table 12, the esterified product having a quinonediazide group, component (C), and other additives are used. Thus, a photosensitive resin composition was prepared. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

[Comparative Examples 2-1 to 2-10]
The same operation as in Example 1-1 is performed except that the novolak resin of component (A) shown in Table 13, the esterified product having a quinonediazide group, component (C), and other additives are used. Thus, a photosensitive resin composition was prepared. About this photosensitive resin composition, the physical property similar to Example 1-1 was evaluated.

From the results shown in Table 6 to Table 11, in Examples 1-1 to 1-27 and Examples 2-1 to 2-28, the resolution is high in the development process for forming the pattern film, and a high residual film ratio is obtained. It was confirmed that there was no development residue and the pattern could be formed with good sensitivity while maintaining the state.
In Comparative Example 1-1, since the component (C) was not added, the resolution was lowered. In Comparative Example 1-2, since the component (B) was excessively reduced, the sensitivity was lowered. In Comparative Example 1-3, since the component (B) was excessively contained, the developability was lowered. In Comparative Example 1-4, since the component (C) was excessively reduced, the resolution was lowered. In Comparative Example 1-5, since the component (C) was excessively contained, the developability was lowered. Since Comparative Examples 1-6 and 7 had a low esterification rate of component (C), the developability decreased. In Comparative Examples 1-8 and 9, since the component (C) did not contain indene, the resolution and the residual film ratio were lowered. In Comparative Example 1-10, since the component (C) was not an indene copolymer but a cyclic olefin resin, the sensitivity was lowered.
In Comparative Example 2-1, since the component (C) was not added, the resolution was lowered. In Comparative Example 2-2, since the component (B) was excessively reduced, the sensitivity was lowered. In Comparative Example 2-3, since the component (B) was excessively contained, the developability was lowered. In Comparative Example 2-4, since the component (C) was excessively reduced, the resolution was lowered. In Comparative Example 2-5, since the component (C) was excessively contained, the developability was lowered. Since Comparative Examples 2-6 and 7 had a low esterification rate of component (C), the developability decreased. In Comparative Examples 2-8 and 9, since the component (C) did not contain indene, the resolution and the residual film ratio were lowered. In Comparative Example 2-10, since the component (C) was not an indene copolymer but a cyclic olefin resin, the sensitivity was lowered.

Claims (5)

A component (A), a component (B), and a component (C) are contained, and the component ratio of each component is 5-50 mass parts of components (B) with respect to 100 mass parts of components (A), A photosensitive resin composition that is 50 parts by weight,
Component (A) is a novolak resin, Component (B) is an esterified product having a quinonediazide group obtained by esterifying a polyfunctional phenolic compound and a quinonediazide compound, and component (C) is represented by the following formula ( (C1) a structural unit derived from indene represented by 1) to (3), (c2) a structural unit derived from an acid anhydride monomer, and (c3) an acid anhydride monomer (c2) As a percentage of the molar ratio (c3) / (c2) between the number of moles of the structural unit (c3) and the number of moles of the structural unit (c2) before esterification. A photosensitive resin composition, which is an indene copolymer having a certain esterification rate of 40% or more.

(Wherein R ¹ is a hydrogen atom or a methyl group)

(In the formula, R ¹ is a hydrogen atom or a methyl group, R ² and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a benzyl group or a cycloalkyl group, at least one of which is hydrogen. atom)   The photosensitive resin composition according to claim 1, wherein the cresol skeleton of the novolak resin of the component (A) is composed of m-cresol and p-cresol, and the molar ratio thereof is 80:20 to 20:80.   The novolak resin of component (A) includes a cresol skeleton and a xylenol skeleton, and the cresol skeleton is selected from at least one of m-cresol and p-cresol, and the xylenol skeleton is 2,3-xylenol or 2,5-xylenol. The photosensitive resin composition according to claim 1, wherein at least one of 3,4, xylenol, and 3,5 xylenol is selected, and a molar ratio thereof is cresol: xylenol = 99: 1 to 50:50.   The flat panel display produced using the photosensitive resin composition of any one of Claims 1-3.   The semiconductor device produced using the photosensitive resin composition of any one of Claims 1-3.