JP4707987B2 - Chemically amplified positive photoresist composition - Google Patents

Description

  The present invention relates to a positive photoresist composition for manufacturing a substrate having an integrated circuit and a liquid crystal display portion formed on one substrate.

Conventionally, as a resist material in the field of liquid crystal display element production using a glass substrate, it is suitable for ghi-line exposure, is relatively inexpensive, has good sensitivity and resolution, and can form a resist pattern with excellent shape. A positive photoresist composition using a novolak resin as an alkali-soluble resin and a quinonediazide group-containing compound as a photosensitive component is often used and reported (Patent Documents 1 to 4 below).
JP 2000-131835 A JP 2001-75272 A JP 2000-181055 A JP 2000-112120 A

Currently, as a next-generation LCD, an integrated circuit portion such as a driver, a DAC (digital-analog converter), an image processor, a video controller, and a RAM is formed at the same time as a display portion on a single glass substrate. Technology development for high-performance LCDs called “LCDs” has been actively conducted (Semiconductor FPD World 2001. 9, pp. 50-67).
Hereinafter, in this specification, a substrate in which an integrated circuit and a liquid crystal display portion are formed on one substrate in this way is referred to as a system LCD for convenience.

For such a system LCD, low-temperature polysilicon formed by a low-temperature process of 600 ° C. or lower, in place of amorphous silicon, is preferable because it has lower electrical resistance and higher mobility than amorphous silicon. Has been.
Therefore, it is desired to develop a photoresist composition suitable for manufacturing a system LCD using low-temperature polysilicon. Various resist materials for system LCD have been reported so far (Patent Documents 5 to 13 below).
Japanese Patent Laid-Open No. 2004-233846 JP 2004-191394 A JP 2004-145207 A JP 2004-144905 A JP 2004-77999 A JP 2004-45707 A Japanese Patent Laid-Open No. 2004-45618 JP 2003-233174 A JP 2003-195596 A

In order to manufacture a TFT made of low-temperature polysilicon, after forming a polysilicon film on a glass substrate by a low-temperature process, P (phosphorus), B (boron), etc. are implanted into the low-temperature polysilicon film. In the “process”, it is necessary to implant a very high concentration of impurities.
This implantation process is performed under high vacuum conditions with a resist pattern formed on a low-temperature polysilicon glass substrate on which a low-temperature polysilicon film is formed on a glass substrate. When the resist pattern on the substrate is heated by the action, there is a problem that the resist pattern changes its shape or a certain component in the resist pattern is gasified to lower the degree of vacuum in the processing chamber.

As a means for solving this problem, it is effective to perform a heat treatment process called “post-baking” before the implantation process. This post-baking is performed under a temperature condition close to the temperature heated during the implantation, for example, Since it is performed at a high temperature of 200 ° C. or higher, it is essential to form a highly heat resistant resist pattern that does not change the pattern shape in the heat treatment.
Therefore, in order to realize the production of the system LCD, it is required that the photoresist composition used therefor has good heat resistance.

  In the system LCD, for example, the pattern size of the display portion is about 2 to 10 μm, whereas the integrated circuit portion is formed with a minute size of about 0.5 to 2.0 μm. Therefore, the photoresist composition for manufacturing the system LCD is required to have the ability to form a fine pattern and a rough pattern in good shape (linearity) at the same time, and has a higher resolution than conventional LCD manufacturing resist materials. The fine depth of focus (DOF) characteristic of a fine pattern is strictly required.

  However, in the field of manufacturing liquid crystal elements, a decrease in sensitivity in the resist material is not preferable because it causes a significant decrease in throughput, and it is desirable to improve the above characteristics without causing a decrease in sensitivity.

  The present invention satisfies the heat resistance, resolution, linearity, and DOF characteristics required for manufacturing a system LCD in which an integrated circuit and a liquid crystal display portion are formed on a single substrate, and has good sensitivity. It is an object of the present invention to provide a photoresist composition.

（式中、ｍ’は０又は１；Ｘは１又は２；Ｒ_１は、１又はそれ以上のＣ１−Ｃ１２アルキル基が置換していてもよいフェニル基、ヘテロアリール基、又は、ｍ’が０の場合はさらにＣ２−Ｃ６アルコキシカルボニル基、フェノキシカルボニル基、ＣＮ；Ｒ_１’はＣ２−Ｃ１２アルキレン基；Ｒ_２はＲ_１と同義；Ｒ_３はＣ１−Ｃ１８アルキル基；Ｒ_３’は、Ｘ＝１のときＲ_３と同義、Ｘ＝２のときＣ２−Ｃ１２アルキレン基、フェニレン基；Ｒ_４、Ｒ_５は独立に水素原子、ハロゲン、Ｃ１−Ｃ６アルキル基；ＡはＳ、Ｏ、ＮＲ_６；Ｒ_６は水素原子、フェニル基を示す。）

（式中、Ａｒは置換又は未置換のフェニル基、ナフチル基；ＲはＣ１〜Ｃ９のアルキル基
；ｎは２又は３の整数を示す。）
The chemically amplified positive photoresist composition of the present invention is a chemically amplified positive photoresist composition for manufacturing a substrate in which an integrated circuit and a liquid crystal display portion are formed on one substrate,
Novolak resin (A-1) in which 20 to 25% of all phenolic hydroxyl groups are protected with acid dissociable, dissolution inhibiting groups, polyhydroxystyrene in which at least part of all phenolic hydroxyl groups are protected with acid dissociable, dissolution inhibiting groups One or more selected from the group consisting of resin (A-2) and compounds represented by the following general formulas (V), (VI), and (X) that generate an acid upon irradiation with i-line (wavelength 365 nm) of the acid generator (B) Ri Na dissolved in an organic solvent, the content of said (a-1) wherein the component (a-2) component, a mass ratio (a-1) / (A- 2) = 0.5-2 .

Wherein m ′ is 0 or 1; X is 1 or 2; R ₁ is a phenyl group, heteroaryl group, or m ′ that may be substituted by one or more C1-C12 alkyl groups. In the case of 0, C2-C6 alkoxycarbonyl group, phenoxycarbonyl group, CN; R ₁ ′ is a C2-C12 alkylene group; R ₂ is synonymous with R ₁ ; R ₃ is a C1-C18 alkyl group; R ₃ ′ is Synonymous with R ₃ when X = 1, C2-C12 alkylene group and phenylene group when X = 2; R ₄ and R ₅ are independently hydrogen atom, halogen, C1-C6 alkyl group; A is S, O, NR ₆ ; R ₆ represents a hydrogen atom or a phenyl group.)

(In the formula, Ar represents a substituted or unsubstituted phenyl group or naphthyl group; R represents a C1-C9 alkyl group; n represents an integer of 2 or 3.)

  In this specification, “structural unit” refers to a monomer unit constituting a polymer.

The value measured using the following GPC (gel permeation chromatography) system is used as the mass average molecular weight (Mw) of the solid content of the photoresist composition in the present specification.
Device name: SYSTEM 11 (product name, Showa Denko)
Precolumn: KF-G (product name, manufactured by Shodex)
Column: KF-805, KF-803, KF-802 (product name, manufactured by Shodex)
Detector: UV41 (product name, manufactured by Shodex), measured at 280 nm.
Solvent etc .: Tetrahydrofuran was allowed to flow at a flow rate of 1.0 ml / min and measured at 35 ° C.
Measurement sample preparation method: The photoresist composition to be measured is adjusted so that the solid content concentration is 30% by mass, and this is diluted with tetrahydrofuran to prepare a measurement sample having a solid content concentration of 0.1% by mass. . Measurement is performed by driving 20 microliters of the measurement sample into the apparatus.

The chemical amplification type positive photoresist composition of the present invention has good sensitivity, excellent heat resistance and high resolution, and is suitable for production of system LCDs and can improve throughput.
Moreover, since it is excellent in linearity, a rough pattern and a fine pattern can be formed on one substrate under the same exposure conditions. Therefore, the resist pattern of the display portion of the system LCD and the finer integrated circuit portion can be obtained at a high resolution at the same time, which is suitable for manufacturing the system LCD.
In addition, in a positive photoresist composition for manufacturing a system LCD, it is important that the depth of focus (DOF) is large to some extent from the viewpoint of manufacturing efficiency, ease of control of manufacturing conditions, and the like. The chemically amplified positive photoresist composition can realize a depth of focus depth (for example, 15 μm or more) practical for a system LCD.

The chemically amplified positive photoresist composition of the present invention (hereinafter sometimes simply referred to as “photoresist composition”) is a chemically amplified positive photoresist for manufacturing a substrate in which an integrated circuit and a liquid crystal display portion are formed on one substrate. Type photoresist composition, wherein at least a part of the total phenolic hydroxyl group is protected with an acid dissociable, dissolution inhibiting group, a novolak resin (A-1), and at least a part of the total phenolic hydroxyl group is an acid dissociable, dissolution inhibiting group A polyhydroxystyrene resin (A-2) protected with, and an acid generator (B) that generates an acid upon irradiation are dissolved in an organic solvent.
Hereinafter, the component (A-1) and the component (A-2) may be collectively referred to as “resin component”.

A novolak resin (A-1) in which at least a part of the total phenolic hydroxyl groups is protected with an acid dissociable, dissolution inhibiting group
In the present invention, the novolak resin (before protection) is obtained by subjecting an aromatic hydroxy compound and an aldehyde or ketone to a condensation reaction under an acidic catalyst.
The component (A-1) can be obtained by reacting a novolak resin before protection with a compound corresponding to the acid dissociable, dissolution inhibiting group.

The novolak resin before protection can be obtained by a condensation reaction of an aromatic compound having a phenolic hydroxyl group (aromatic hydroxy compound) and an aldehyde or ketone.
Examples of the aromatic hydroxy compound include phenol; cresols such as m-cresol, p-cresol, o-cresol; 2,3-xylenol, 2,5-xylenol, 3,5-xylenol, 3,4-xylenol. Xylenols such as m-ethylphenol, p-ethylphenol, o-ethylphenol, 2,3,5-trimethylphenol, 2,3,5-triethylphenol, 4-tert-butylphenol, 3-tert-butylphenol, Alkylphenols such as 2-tert-butylphenol, 2-tert-butyl-4-methylphenol, 2-tert-butyl-5-methylphenol; p-methoxyphenol, m-methoxyphenol, p-ethoxyphenol, m-ethoxy Phenol, p- Alkoxyphenols such as lopoxyphenol and m-propoxyphenol; isopropenylphenols such as o-isopropenylphenol, p-isopropenylphenol, 2-methyl-4-isopropenylphenol and 2-ethyl-4-isopropenylphenol And arylphenols such as phenylphenol; polyhydroxyphenols such as 4,4′-dihydroxybiphenyl, bisphenol A, resorcinol, hydroquinone, pyrogallol, and the like. These may be used alone or in combination of two or more.

Examples of the aldehydes include formaldehyde, paraformaldehyde, trioxane, acetaldehyde, propionaldehyde, butyraldehyde, trimethylacetaldehyde, acrolein, crotonaldehyde, cyclohexanealdehyde, furfural, furylacrolein, benzaldehyde, terephthalaldehyde, phenylacetaldehyde, α-phenylpropyl. Aldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p- Chlorobenzaldehyde, cinnamic acid Examples include aldehydes. These may be used alone or in combination of two or more.
Among these aldehydes, formaldehyde is preferable because it is easily available. In particular, in order to improve heat resistance, it is preferable to use a combination of hydroxybenzaldehydes and formaldehyde.

  Examples of the ketones include acetone, methyl ethyl ketone, diethyl ketone, and diphenyl ketone. These may be used alone or in combination of two or more. Furthermore, aldehydes and ketones may be used in appropriate combination.

  A condensation reaction product of an aromatic hydroxy compound and an aldehyde or ketone can be produced by a known method in the presence of an acidic catalyst. In this case, hydrochloric acid, sulfuric acid, formic acid, oxalic acid, paratoluenesulfonic acid, etc. can be used as the acidic catalyst.

(A-1) At least a part of the total phenolic hydroxyl groups in the component is protected with so-called acid dissociable, dissolution inhibiting groups.
An acid dissociable, dissolution inhibiting group (hereinafter sometimes referred to as “acid dissociable inhibiting group”) is a resist pattern forming process using a photoresist composition. It has an alkali dissolution inhibiting property that makes it soluble or insoluble, dissociates after exposure by the action of an acid generated from the component (B) described later, and changes the entire component (A-1) to alkali-soluble. .
The novolak resin of component (A-1) is hardly soluble in alkali or insoluble in alkali by replacing the hydrogen atom of the phenolic hydroxyl group with such an acid dissociable inhibiting group in at least a part of the total phenolic hydroxyl group. And the acid dissociable inhibitory group causes alkali dissociation by causing dissociation.
Such an acid dissociable, dissolution inhibiting group may be any group that can be dissociated by an acid generated from the later-described component (B), such as 1-ethoxymethyl group, 1-ethoxyethyl group, 1-propoxymethyl group, 1 -Alkoxyalkyl groups such as propoxyethyl group, 1-n-butoxymethyl group, 1-iso-butoxymethyl group, 1-tert-butoxymethyl group; t-butoxycarbonyl group, t-butoxycarbonylmethyl group, t-butoxy Alkoxycarbonylalkyl group such as carbonylethyl group; tetrahydrofuranyl group; tetrahydropyranyl group; linear or branched acetal group; cyclic acetal group; trialkylsilyl group such as trimethylsilyl group, triethylsilyl group and triphenylsilyl group Is mentioned.
Among them, an ethyl vinyl group (ethoxyethyl group) represented by the following chemical formula (IV-1) and a t-butoxycarbonyl group represented by the following chemical formula (IV-2) are used to obtain a photoresist composition having excellent resolution. The ethyl vinyl group is particularly preferable.

  The preferred range of the weight average molecular weight (Mw) of the novolak resin before being protected with the acid dissociable, dissolution inhibiting group is 1000 to 200000, preferably 2000 to 50000, more preferably 3000 to 30000. When the Mw of the component (A-1) is equal to or higher than the lower limit, the tendency of the resolution to be lowered can be suppressed, and when it is equal to or lower than the upper limit, the coating property of the photoresist composition is prevented from being deteriorated. it can.

-Polyhydroxystyrene resin (A-2) in which at least a part of all phenolic hydroxyl groups is protected with acid dissociable, dissolution inhibiting groups
In the present invention, polyhydroxystyrene (before protection) is a concept including a polymer composed of hydroxystyrene (hydroxystyrene homopolymer) and derivatives thereof. Examples of such polyhydroxystyrene include a vinylphenol homopolymer, a copolymer of vinylphenol and a comonomer copolymerizable therewith, and the like. Here, examples of the comonomer include acrylic acid derivatives, acrylonitrile, methacrylic acid derivatives, methacrylonitrile, styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, p-methoxystyrene, p-chlorostyrene, and other styrene. Derivatives. Among polyhydroxystyrenes, hydroxystyrene homopolymers, hydroxystyrene-styrene copolymers and the like are preferable.
In the polyhydroxystyrene resin as the component (A-2), as in the component (A-1), the hydrogen atom of the phenolic hydroxyl group is substituted with an acid dissociable inhibiting group in at least a part of the total phenolic hydroxyl group. In other words, it may be any one that exhibits poor alkali solubility or alkali insolubility, and can be alkali-soluble by dissociation of the acid dissociability-inhibiting group from the phenolic hydroxyl group.
Such a component (A-2) reacts a polyhydroxystyrene resin having no acid dissociable, dissolution inhibiting group (polyhydroxystyrene resin before protection) with a compound corresponding to the acid dissociable, dissolution inhibiting group. Can be obtained.

  The hydroxystyrene includes derivatives thereof. Specifically, the hydroxystyrene structural unit is represented by the following general formula (II).

（式中、Ｒ_０は水素原子または低級アルキル基、ｍは１〜３の整数を表す。）

(In the formula, R ₀ represents a hydrogen atom or a lower alkyl group, and m represents an integer of 1 to 3.)

R ₀ is a hydrogen atom or a lower alkyl group (for example, having 1 to 5 carbon atoms (which may be linear or branched), preferably a methyl group), preferably a hydrogen atom. The position of the hydroxyl group may be any of the o-position, the m-position, and the p-position, but the p-position is preferred because it is readily available and inexpensive.
In the hydroxystyrene-styrene copolymer, styrene includes styrene in which the benzene ring is not substituted with an alkyl group and a compound in which the benzene ring is substituted with a lower alkyl group having 1 to 5 carbon atoms. The number of lower alkyl groups as substituents is 1 to 3.

  The acid dissociable, dissolution inhibiting group in the component (A-2) is dissociated by an acid generated from the component (B) described later, like the acid dissociable, dissolution inhibiting group in the component (A-1) described above. I just need it. Examples and preferred examples of the acid dissociable, dissolution inhibiting group are the same as those shown in the description of the component (A-1).

  The preferred range of the weight average molecular weight (Mw) of the polyhydroxystyrene resin before being protected with an acid dissociable, dissolution inhibiting group is 1000 to 200000, preferably 2000 to 50000, more preferably 3000 to 30000. is there. When the Mw of the polyhydroxystyrene resin is not less than the above lower limit value, the tendency of the resolution to be lowered can be suppressed, and when it is not more than the above upper limit value, it is possible to prevent the coating property of the photoresist composition from being deteriorated.

Since the positive photoresist composition of the present invention exhibits a chemical amplification type mechanism, the development contrast between the unexposed portion and the exposed portion is strong, and the above-mentioned components (A-1) and (A-2) are used as resin components. ) By including both components, good heat resistance, resolution, linearity and DOF characteristics can be expressed.
As for the resolution, the resolution under the low NA condition is particularly high compared to the prior art.
For example, under a low NA condition of NA = 0.14, the minimum dimension 1.1-1.0 μm has a line and space (L & S) resolution. With respect to heat resistance, for example, even when a resist pattern formed using this photoresist composition is heated at about 200 ° C., no change in bottom dimension is observed, and the pattern shape is maintained well.
When the component (A-1) is used alone as the resin component, it is particularly difficult to realize high resolution. On the other hand, when the component (A-2) is used alone, it is particularly difficult to realize high heat resistance.

The content ratio of the component (A-1) and the component (A-2) in the photoresist composition of the present invention is (A-1) / (A-2) = 0.1 / 1 to 10/1 in mass ratio. It is preferable that When the content ratio is within this range, a good resolution (for example, about 1.1 to 1.0 μm L & S at NA = 0.14) can be realized particularly stably under low NA conditions, and heat resistance, linearity and It becomes possible to form a resist pattern having very excellent DOF characteristics.
The content ratio of the component (A-1) and the component (A-2) is more preferably 1/1 to 5/1, and most preferably 4/1.
In the photoresist composition of the present invention, known resin components used in the resist composition other than the components (A-1) and (A-2) can be blended, but preferably ( It is desirable that the total amount of the component (A-1) and the component (A-2) is 70% by mass or more, further 80% by mass or more, and most preferably 100% by mass among all the resin components.

-Acid generator (B) that generates acid upon exposure
The component (B) is not particularly limited, and is a photoacid generator conventionally known as a material for a chemically amplified positive photoresist composition, such as a sulfonyldiazomethane acid generator, an onium salt acid generator, An oxime sulfonate acid generator or the like can be used.

  In particular, in the production of LCD, ultraviolet rays in which g-line, h-line, and i-line coexist may be used, and as the component (B), a compound having a high acid generation efficiency when irradiated with such ultraviolet rays is preferable. . Further, in order to improve the resolution, i-line having a short wavelength is preferably used. Furthermore, in the production of the system LCD, since i-line tends to be mainly used, as the component (B), A compound that generates an acid upon irradiation with i-line is preferable, and a compound with high acid generation efficiency for i-line exposure is particularly preferable.

As the component (B), for example, the following compounds are preferably used because of high acid generation efficiency for i-line exposure.
Those represented by the following general formulas (V) and (VI).

Wherein m ′ is 0 or 1; X is 1 or 2; R ₁ is a phenyl group, a heteroaryl group, or the like, optionally substituted by one or more C1-C12 alkyl groups, or m ′ When R is 0, C2-C6 alkoxycarbonyl group, phenoxycarbonyl group, CN and the like; R ₁ 'is a C2-C12 alkylene group and the like; R ₂ is synonymous with R ₁ ; R ₃ is a C1-C18 alkyl group and the like; R ₃ 'is synonymous with R ₃ when X = 1, C2-C12 alkylene group, phenylene group and the like when X = 2; R ₄ and R ₅ are independently a hydrogen atom, halogen, C1-C6 alkyl group and the like A represents S, O, NR _{6 and the} like; R ₆ represents a hydrogen atom, a phenyl group, etc.) (USP 6004724). Specific examples include thiolene-containing oxime sulfonates represented by the following formula (VII).

  Further, the following formula (VIII)

(In formula, R < ⁶ >, R < ⁷ > shows a C1-C3 alkyl group, respectively.)
A bis (trichloromethyl) triazine compound represented by the formula (IX) or the following formula (IX):

(In the formula, Z represents a 4-alkoxyphenyl group or the like.)
And a bis (trichloromethyl) triazine compound represented by the formula (JP-A-6-289614, JP-A-7-134411).

Specific examples of the triazine compound (VIII) include 2- [2- (3,4-dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-methoxy-4-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-methoxy-4-propoxyphenyl) ethenyl ] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-ethoxy-4-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1, 3,5-triazine, 2- [2- (3,4-diethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-ethoxy -4-Pro Xylphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy-4-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy-4-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-dipropoxyphenyl) ethenyl] -4,6-bis (trichloromethyl)-, 3,5-triazine and the like. These triazine compounds may be used alone or in combination of two or more.

  On the other hand, as the triazine compound (IX) used in combination with the triazine compound (VIII) as desired, for example, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3, 5-triazine, 2- (4-ethoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-propoxyphenyl) -4,6-bis (trichloromethyl)- 1,3,5-triazine, 2- (4-butoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxynaphthyl) -4,6-bis ( Trichloromethyl) -1,3,5-triazine, 2- (4-ethoxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-propoxy) Naphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-butoxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-Methoxy-6-carboxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxy-6-hydroxynaphthyl) -4,6-bis (trichloromethyl) ) -1,3,5-triazine, 2- [2- (2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (5-methyl) -2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (5-ethyl-2-furyl) ethenyl] -4,6-bis (trichloro Methyl) -1,3,5-tri Gin, 2- [2- (5-propyl-2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,5-dimethoxyphenyl) Ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-methoxy-5-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1 , 3,5-triazine, 2- [2- (3-methoxy-5-propoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3 -Ethoxy-5-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,5-diethoxyphenyl) ethenyl] -4,6- Bis (trichloromethyl)- 1,3,5-triazine, 2- [2- (3-ethoxy-5-propoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- ( 3-propoxy-5-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy-5-ethoxyphenyl) ethenyl] -4, 6-bis (trichloromethyl) -1,3,5-triazine, 2-2 (3,5-dipropoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (3,4-methylenedioxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-methylenedioxyphenyl) ethenyl] -4 , 6-bis ( Rikuroromechiru) -1,3,5-triazine. These triazine compounds may be used alone or in combination of two or more.

  Moreover, following formula (X)

(Wherein, Ar represents a substituted or unsubstituted phenyl group or naphthyl group; R represents a C1-C9 alkyl group; n represents an integer of 2 or 3). These compounds may be used alone or in combination of two or more. Among the compounds exemplified above, in particular, the compound represented by the above formula (VII) and the compound represented by the following formula (XI) are preferably used because of excellent acid generation efficiency with respect to i-line.

(B) A component can be used 1 type or in mixture of 2 or more types.
The blending amount of the component (B) is preferably 1 to 30 parts by mass, more preferably 1 to 10 parts by mass with respect to 100 parts by mass in total of the component (A-1) and the component (A-2). .

・ Basic compounds (C)
In the photoresist composition of the present invention, it is preferable to blend a basic compound (preferably amines) as the component (C) in order to enhance the stability of retention.
The compound is not particularly limited as long as it has compatibility with the photoresist composition, and examples thereof include compounds described in JP-A-9-6001.

  In particular, the effect of suppressing the amount of acid component by-produced in the resist composition over time by blending a relatively bulky specific basic compound (c1) represented by the following general formula (I) In addition, the long-term storage stability of the resist composition can be improved.

In the general formula (I), one or more (preferably 2 or more, most preferably 3) of X, Y and Z are the following (1) to (4):
(1) an alkyl group having 4 or more carbon atoms,
(2) a cycloalkyl group having 3 or more carbon atoms,
(3) phenyl group,
(4) A group selected from aralkyl groups.
Among the X, Y, and Z, those not (1) to (4) are
(1 ′) an alkyl group having 3 or less carbon atoms,
(2 ′) A group or atom selected from hydrogen atoms.
X, Y and Z may be the same or different from each other, but when two or more of X, Y and Z are groups selected from the above (1) to (4), The groups corresponding to these are preferably the same from the viewpoint of the stability of the effect.

(1) Alkyl group having 4 or more carbon atoms In the case of (1), if the carbon number is less than 4, it is difficult to improve the temporal stability. The number of carbon atoms is preferably 5 or more, particularly 8 or more. Although the upper limit is not particularly limited, it is preferably 20 or less, particularly preferably 15 or less from the viewpoint that a stable effect over time is recognized and it is commercially available. In addition, when it exceeds 20, basic strength will become weak and the effect of storage stability will fall.
The alkyl group may be linear or branched.
Specifically, for example, n-decyl group, n-octyl group, n-pentyl group and the like are preferable.

(2) Cycloalkyl group having 3 or more carbon atoms Among the cycloalkyl group, a cycloalkyl group having 4 to 8 carbon atoms is commercially available, and is excellent in the effect of improving the temporal stability. Particularly preferred is a cyclohexyl group having 6 carbon atoms.

(4) Aralkyl group An aralkyl group is represented by the general formula, -R'-P (R 'is an alkylene group, and P is an aromatic hydrocarbon group).
Examples of P include a phenyl group and a naphthyl group, and a phenyl group is preferable.
The carbon number of R ′ may be 1 or more, preferably 1 to 3.
As the aralkyl group, for example, a benzyl group, a phenylethyl group and the like are preferable.

  Of X, Y, and Z, those other than (1) to (4) are groups or atoms selected from the above (1 ') and (2').

(1 ′) may be either linear or branched. In particular, a methyl group and an ethyl group are preferable.
(C1) As a component, what comprises a tertiary amine is preferable. That is, among X, Y, and Z, those not (1) to (4) are preferably selected from (1 ′).
Specific examples of the component (c1) include tri-n-decylamine, methyl-di-n-octylamine, tri-n-pentylamine, N, N-dicyclohexylmethylamine, tribenzylamine and the like. It is done.
Among these, at least one selected from tri-n-decylamine, methyl-di-n-octylamine, and tri-n-pentylamine is preferable, and tri-n-decylamine is particularly preferable.

(C) component can be used 1 type or in mixture of 2 or more types.
(C) component is 0.01-5.0 mass parts with respect to a total of 100 mass parts of said (A-1) component and (A-2) component, especially 0.1-1.0 mass part. It is preferable from the point of an effect to mix | blend in the range.

Organic Solvent The organic solvent in the photoresist composition of the present invention can be used without particular limitation as long as it can be used for a chemically amplified positive photoresist composition.
Examples of the organic solvent include ester solvents and non-ester solvents.
Examples of the ester solvent include propylene glycol monoalkyl ether acetate (for example, propylene glycol monomethyl ether acetate (PGMEA)) and lactic acid ester (for example, ethyl lactate).
Non-ester solvents include ketones, polyhydric alcohols and derivatives thereof, and cyclic ethers.
Examples of ketones include acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, and 2-heptanone. Examples of the polyhydric alcohols and derivatives thereof include ethylene glycol, propylene glycol, diethylene glycol, or monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, or monophenyl ether thereof. Examples of cyclic ethers include dioxane.

Since the ester solvent is a reaction product of an organic carboxylic acid and an alcohol, it contains an organic carboxylic acid that is a free acid.
Therefore, in a resist composition not containing the component (c1) or a resist composition not containing a storage stabilizer described later, it is preferable to select a non-ester solvent that does not contain such a free acid. Ketones (ketone solvents) are preferred. Among these, 2-heptanone is preferable from the viewpoint of coating properties.

In addition, both ester solvents and non-ester solvents may decompose over time to produce an acid, but in the presence of the component (c1) or in the presence of a storage stabilizer described later, The decomposition reaction is suppressed. The effect is particularly remarkable in an ester solvent, and in the presence of the component (c1) and a storage stabilizer, an ester solvent is preferable, and propylene glycol monoalkyl ether acetate such as PGMEA is particularly preferable.
In addition, as an acid component by-produced by the decomposition, for example, in the case of 2-heptanone, it has been confirmed that formic acid, acetic acid, propionic acid and the like are generated.
The organic solvent can be used alone or in combination.
In the photoresist composition of the present invention, the organic solvent contains at least one selected from propylene glycol monoalkyl ether acetate and 2-heptanone in order to improve storage stability and to ensure stable coating properties. It is preferable to use it.

In addition to the above, the chemical amplification type positive photoresist composition of the present invention preferably contains the following storage stabilizer as required.
The storage stabilizer is not particularly limited as long as it has an action of suppressing the decomposition reaction of the solvent, and examples thereof include an antioxidant as described in JP-A No. 58-194634. it can. As the antioxidant, phenolic compounds and amine compounds are known, and phenolic compounds are particularly preferable. Among them, 2,6-di (tert-butyl) -p-cresol and derivatives thereof are ester solvents, It is effective in terms of deterioration of the ketone solvent, is commercially available, is inexpensive, and is preferable in view of excellent storage stability. In particular, the effect of preventing deterioration of propylene glycol monoalkyl ether acetate and 2-heptanone is extremely excellent.
The blending amount of the storage stabilizer is 0.01 to 3 parts by weight, particularly 0.1 to 1.0 parts by weight, based on 100 parts by weight of the total amount of the components (A-1) and (A-2). The range of parts is preferred.

  In addition, the photoresist composition of the present invention includes an additive resin and a plasticizer for improving the compatibility of the resist film as necessary, for example, as long as the object of the present invention is not impaired. , Stabilizers, surfactants, colorants to make the developed image more visible, sensitizers and antihalation dyes to improve the sensitization effect, adhesion additives, etc. Products can be included.

  The photoresist composition of the present invention preferably has a mass average molecular weight (Mw) of 3000 to 100,000, more preferably 5,000 to 50,000. When the Mw of the photoresist composition is 3000 to 100,000, the photoresist composition is further improved with respect to high heat resistance, high resolution, and depth of focus characteristics (DOF characteristics). The solid content of the positive photoresist composition is the total of the components (A-1), (A-2), (B) and other components used as desired.

The positive photoresist composition of the present invention is produced by dissolving the component (A-1), the component (A-2), the component (B), and other components as desired in an organic solvent. Can do.
The amount of the organic solvent used is preferably such that when the components (A-1), (A-2), (B) and other components used as desired are dissolved, a uniform positive photoresist composition is obtained. Is adjusted as appropriate. The solid content is preferably 10 to 50% by mass, more preferably 20 to 35% by mass.

As a method for carrying out the step of adjusting the solid content Mw of the photoresist composition so as to be within the above-mentioned preferred range, for example, (1) Before mixing, the Mw after mixing all the components is within the above range. A method of adjusting the Mw of the resin component to an appropriate range in advance by performing a fractionation operation on the component (A-1) and the component (A-2), (2) Different Mw (A-1 ) Component or a plurality of components (A-2) are prepared, and these are appropriately blended to adjust the solid content Mw to the above range.
Among these preparation methods, the preparation method according to the above (2) is more preferable in terms of easy adjustment of resist molecular weight and sensitivity adjustment.

(Method for forming resist pattern)
The following is a preferred example of a method for producing a system LCD using the photoresist composition of the present invention.
First, the photoresist composition of the present invention is applied to a substrate with a spinner or the like to form a coating film.
As the substrate, a glass substrate provided with a silicon film is preferable. In the formation of the silicon film, amorphous silica is usually used, but in the field of the system LCD, low temperature polysilicon or the like is preferable. In addition, a large substrate of 300 mm × 400 mm or more, in particular, 550 mm × 650 mm or more can be used.

Next, the substrate on which the coating film is formed is heat-treated (prebaked) at 90 to 140 ° C., for example, to remove the remaining solvent, and a resist film is formed. As a pre-baking method, it is preferable to perform proximity baking with a gap between the hot plate and the substrate.
Next, the resist film is selectively exposed using a mask on which both a mask pattern for an integrated circuit and a mask pattern for a liquid crystal display portion are drawn.
As the light source used here, it is preferable to use i-line (365 nm) in order to form a fine pattern. The exposure process employed in this exposure is preferably an exposure process under a low NA condition with an NA of 0.3 or less, preferably 0.2 or less, more preferably 0.15 or less. By employing an exposure process under a low NA condition, a single exposure area can be increased, and throughput can be improved.

Next, heat treatment (post-exposure baking: PEB) is applied to the resist film after selective exposure. Examples of PEB methods include proximity baking that provides a gap between the hot plate and the substrate, and direct baking that does not have a gap. In order to obtain a diffusion effect by PEB without causing warping of the substrate, A method of performing direct baking after proximity baking is preferable. The heating temperature is preferably 90 to 150 ° C, particularly 100 to 140 ° C.
When the resist film after PEB is subjected to development using a developer, for example, an alkaline aqueous solution such as an aqueous solution of 1 to 10% by mass of tetramethylammonium hydroxide (TMAH), the exposed portion is dissolved and removed, and the substrate A resist pattern for the integrated circuit and a resist pattern for the liquid crystal display portion are simultaneously formed thereon.
Next, the resist pattern can be formed by washing away the developer remaining on the resist pattern surface with a rinse solution such as pure water.

In the selective exposure step, it is preferable to use a mask on which a mask pattern for forming a resist pattern of 2.0 μm or less and a mask pattern for forming a resist pattern of more than 2.0 μm are drawn as the mask.
Since the chemically amplified positive photoresist composition of the present invention is excellent in linearity, a resist pattern faithfully reproducing both a rough pattern and a fine pattern of the mask pattern can be obtained. Therefore, a resist pattern for an integrated circuit having a pattern dimension of 2.0 μm or less and a resist pattern for a liquid crystal display part having a pattern size of more than 2.0 μm can be simultaneously formed on the substrate.

  EXAMPLES Next, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited to a following example.

[Evaluation Method of Positive Photoresist Composition]
The following evaluation methods for various physical properties (1) to (5) of the positive photoresist compositions of the following examples or comparative examples are shown below.
(1) Sensitivity evaluation: A positive photoresist composition is coated on a glass substrate (550 mm × 650 mm) on which a Ti film is formed using a resist coating apparatus for large substrates (device name: TR36000 manufactured by Tokyo Ohka Kogyo Co., Ltd.). After that, pre-baking was performed by proximity baking with an interval of about 1 mm under a heating condition of 90 ° C. for 90 seconds to form a resist film having a thickness of 1.5 μm.
Next, through a test chart mask (reticle) on which a mask pattern for reproducing a 1.5 μmL & S resist pattern and a 3.0 μmL & S resist pattern is drawn simultaneously, an i-line exposure apparatus (apparatus name: FX-702J, Nikon Corporation) (Manufactured; NA = 0.14), selective exposure was performed with an exposure amount (Eop exposure amount) capable of faithfully reproducing 1.5 μmL & S.
Next, PEB was applied by proximity bake with an interval of 0.5 mm under the condition of 110 ° C. for 90 seconds.
Next, after developing for 90 seconds using a 23.degree. C., 2.38 mass% TMAH aqueous solution, it was rinsed with pure water for 30 seconds and spin-dried.
As an index for sensitivity evaluation, an exposure amount (Eop, unit: mJ) capable of faithfully reproducing a 1.5 μmL & S resist pattern was used.

(2) DOF characteristic evaluation: In the above Eop exposure amount, the focus is appropriately shifted up and down, and the width of the depth of focus (DOF) obtained within the range of the dimensional change rate of 1.5 μmL & S is ± 10% is obtained in μm. It was.
(3) Evaluation of heat resistance: In the above Eop exposure amount, a substrate on which 1.5 μmL & S was drawn was left on a hot plate set at 200 ° C. for 30 minutes, and then the cross-sectional shape was observed. As a result, 1.5 μmL & S bottom dimension change rate was within ± 3%, ○, 3-5% or −5 to −3% within the range Δ, ± 5% exceeded Things were represented as x.
(4) Resolution evaluation: The limiting resolution at the Eop exposure amount was determined.
(5) Linearity evaluation: The cross-sectional shape of the 3.0 μmL & S resist pattern obtained with the above Eop exposure amount was observed with a SEM (scanning electron microscope) photograph, and the reproducibility of the 3.0 μmL & S resist pattern was evaluated. Those in which the dimensional change rate of 3.0 μmL & S was within ± 10% were indicated as “◯”, and those exceeding ± 10% were indicated as “×”.

Hereinafter, “mass average molecular weight” indicates a polystyrene-reduced mass average molecular weight by gel permeation chromatography.
In the following examples, the following were used as the component (A-1).
-Component (A-1) A novolak resin in which 20 to 25% of all phenolic hydroxyl groups are protected with 1-ethoxyethyl group.
In addition, the novolak resin before protecting with 1-ethoxyethyl group uses a mixture of m-cresol / p-cresol = 4/6 (molar ratio) as phenols, and formaldehyde / salicylaldehyde = 3/1 as a condensing agent. What refine | purified the alkali-soluble novolak resin of polystyrene conversion mass mean molecular weight (Mw) 5000 synthesize | combined by the conventional method using the mixture of (molar ratio) by the reprecipitation method and the washing process by an acid aqueous solution was used.
The reprecipitation method was performed by dissolving the resin in a 30% by mass aqueous methanol solution and adding pure water to the resin to precipitate the resin.
The washing treatment with the acid aqueous solution was performed by washing the deposited resin once with a hydrochloric acid aqueous solution and twice with pure water.

Moreover, the following were used as the component (A-2).
-(A-2) component Polyhydroxystyrene resin in which 30 to 40% of all phenolic hydroxyl groups are protected with 1-ethoxyethyl group.
The Mw of the polyhydroxystyrene resin before protecting with 1-ethoxyethyl group was 20000.

Example 1
Component (A-1) (Mw before being protected with an acid dissociable, dissolution inhibiting group: 5000): 33 parts by mass
Component (A-2) (Mw before being protected with an acid dissociable, dissolution inhibiting group: 20000): 17 parts by mass (B) component [compound of the above formula (XI)]: 3 parts by mass (C) component [ Tri-n-decylamine]: 0.2 part by mass The above-mentioned various components are dissolved in PGMEA, and further 500 ppm of XR-104 (trade name; manufactured by Dainippon Ink Co., Ltd.) is added as a surfactant. Then, this was filtered using a membrane filter having a pore size of 0.2 μm to prepare a photoresist composition.
The physical properties of (1) to (5) were evaluated for this photoresist composition. The results are shown in Table 1 below.

(Example 2)
In Example 1, the amount of the component (A-1) was changed from 33 parts by weight to 25 parts by weight, and the amount of the component (A-2) was changed from 17 parts by weight to 25 parts by weight. In the same manner as in No. 1, a photoresist composition was prepared. The physical properties of (1) to (5) were evaluated for this photoresist composition. The results are shown in Table 1 below.

(Example 3)
In Example 1, the amount of the component (A-1) was changed from 33 parts by weight to 17 parts by weight, and the amount of the component (A-2) was changed from 17 parts by weight to 33 parts by weight. In the same manner as in No. 1, a photoresist composition was prepared. The physical properties of (1) to (5) were evaluated for this photoresist composition. The results are shown in Table 1 below.

(Comparative Example 1)
In Example 1, the amount of the component (A-1) was changed from 33 parts by weight to 50 parts by weight, and the amount of the component (A-2) was changed from 17 parts by weight to 0 parts by weight. In the same manner as in No. 1, a photoresist composition was prepared. The physical properties of (1) to (5) were evaluated for this photoresist composition. The results are shown in Table 1 below.

(Comparative Example 2)
In Example 1, the amount of the component (A-1) was changed from 33 parts by weight to 0 parts by weight, and the amount of the component (A-2) was changed from 17 parts by weight to 50 parts by weight. In the same manner as in No. 1, a photoresist composition was prepared. The physical properties of (1) to (5) were evaluated for this photoresist composition. The results are shown in Table 1 below.

As is clear from Table 1, in the examples according to the present invention, the sensitivity, the DOF characteristics, the heat resistance, the resolution, and the linearity are all good, and it is shown that they are suitable for manufacturing a system LCD. . On the other hand, in Comparative Example 1 in which the polyhydroxystyrene resin was not used, sensitivity, DOF characteristics, heat resistance, resolution, and linearity were all. In Comparative Example 2 in which the novolac resin was not used, heat resistance and linearity were respectively. It was inferior to the examples and was insufficient for the production of the system LCD.

Claims (5)

A chemically amplified positive photoresist composition for manufacturing a substrate in which an integrated circuit and a liquid crystal display portion are formed on one substrate,
Novolak resin (A-1) in which 20 to 25% of all phenolic hydroxyl groups are protected with acid dissociable, dissolution inhibiting groups, polyhydroxystyrene in which at least part of all phenolic hydroxyl groups are protected with acid dissociable, dissolution inhibiting groups One or more selected from the group consisting of resin (A-2) and compounds represented by the following general formulas (V), (VI), and (X) that generate an acid upon irradiation with i-line (wavelength 365 nm) of the acid generator (B) Ri Na dissolved in an organic solvent, the content of said (a-1) wherein the component (a-2) component, a mass ratio (a-1) / (A- 2) A chemically amplified positive photoresist composition, wherein 0.5 to 2 .

Wherein m ′ is 0 or 1; X is 1 or 2; R ₁ is a phenyl group, heteroaryl group, or m ′ that may be substituted by one or more C1-C12 alkyl groups. In the case of 0, C2-C6 alkoxycarbonyl group, phenoxycarbonyl group, CN; R ₁ ′ is a C2-C12 alkylene group; R ₂ is synonymous with R ₁ ; R ₃ is a C1-C18 alkyl group; R ₃ ′ is Synonymous with R ₃ when X = 1, C2-C12 alkylene group and phenylene group when X = 2; R ₄ and R ₅ are independently hydrogen atom, halogen, C1-C6 alkyl group; A is S, O, NR ₆ ; R ₆ represents a hydrogen atom or a phenyl group.)

(In the formula, Ar represents a substituted or unsubstituted phenyl group or naphthyl group; R represents a C1-C9 alkyl group; n represents an integer of 2 or 3.) Chemical amplification type positive photoresist composition according to claim 1 containing basic compound (C) further. The chemical amplification type positive photoresist composition according to claim 2 , wherein the component (C) contains a compound (c1) represented by the following general formula (I).

[Wherein one or more of X, Y and Z are the following (1) to (4)
(1) an alkyl group having 4 or more carbon atoms,
(2) a cycloalkyl group having 3 or more carbon atoms,
(3) phenyl group,
(4) an aralkyl group,
A group selected from
Among the X, Y, and Z, those that are not (1) to (4) are as follows:
(1 ′) an alkyl group having 3 or less carbon atoms,
(2 ′) A group or atom selected from hydrogen atoms. ] The content of component (C), the component (A-1) and (A-2) relative to total 100 parts by weight of the component according to claim 2 or 3 which is 0.01 to 5.0 parts by weight Chemically amplified positive photoresist composition. The organic solvent, chemically amplified positive photoresist composition according to any one of claims 1 to 4, characterized in that it comprises at least one selected from propylene glycol monoalkyl ether acetate and 2-heptanone.