KR20060051216A - Chemical amplification type positive photoresist composition - Google Patents

Abstract

The photoresist composition is a chemically amplified positive type photoresist composition for manufacturing a substrate in which an integrated circuit and a liquid crystal display portion are formed on one substrate, wherein at least a part of the entire phenolic hydroxyl group is protected by an acid dissociable, dissolution inhibiting agent ( A-1), a polyhydroxystyrene resin (A-2) in which at least a part of the entire phenolic hydroxyl group is protected by an acid dissociable, dissolution inhibiting agent, and an acid generator (B) which generates an acid by irradiation to an organic solvent It is a chemically amplified positive photoresist composition characterized by melting.

Description

Chemically Amplified Positive Photoresist Composition {CHEMICAL AMPLIFICATION TYPE POSITIVE PHOTORESIST COMPOSITION}

[Patent Document 1] Japanese Unexamined Patent Publication No. 2000-131835

[Patent Document 2] Japanese Unexamined Patent Publication No. 2001-75272

[Patent Document 3] Japanese Unexamined Patent Publication No. 2000-181055

[Patent Document 4] Japanese Unexamined Patent Publication No. 2000-112120

[Patent Document 5] Japanese Unexamined Patent Publication No. 2004-233846

[Patent Document 6] Japanese Unexamined Patent Publication No. 2004-191394

[Patent Document 7] Japanese Unexamined Patent Publication No. 2004-145207

[Patent Document 8] Japanese Unexamined Patent Publication No. 2004-144905

[Patent Document 9] Japanese Unexamined Patent Publication No. 2004-77999

[Patent Document 10] Japanese Unexamined Patent Publication No. 2004-45707

[Patent Document 11] Japanese Unexamined Patent Publication No. 2004-45618

[Patent Document 12] Japanese Unexamined Patent Publication No. 2003-233174

[Patent Document 13] Japanese Unexamined Patent Publication No. 2003-195496

Technical Field

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

This application claims priority with respect to Japanese Patent Application No. 2004-269704 for which it applied on September 16, 2004, and uses the content here.

Background

As a resist material in the liquid crystal display element manufacturing field which used the glass substrate until now, since it is suitable for ghi line exposure, it is comparatively inexpensive, since it can form the resist pattern which is excellent in a sensitivity, the resolution, and is excellent in shape, it is alkali-soluble. Many positive type photoresist compositions using a novolak resin as the resin and a quinonediazide group-containing compound as the photosensitive component have been used and reported (Patent Documents 1 to 4).

Currently, as a next-generation LCD, an integrated circuit portion such as a driver, a digital-to-analog converter (DAC), an image processor, a video controller, and a RAM is formed simultaneously with the display portion on a single glass substrate, called a so-called “system LCD”. Technology development for high-performance LCDs is being 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 as described above is referred to as a system LCD for convenience.

Instead of amorphous silicon, such low temperature polysilicon formed in a low temperature process of 600 ° C. or less is known to be preferable in such a system LCD in view of its high electrical resistance and low mobility compared to amorphous silicon.

Accordingly, there is a demand for the development of photoresist compositions suitable for the production of system LCDs using low temperature polysilicon. So far, various reports have been made on resist materials for system LCDs (Patent Documents 5 to 13).

In order to manufacture a TFT made of low temperature polysilicon, a polysilicon film is formed on a glass substrate in a low temperature process, and then P (phosphorus), B (boron), etc. are injected into the low temperature polysilicon film, so-called "implantation process". It is known that it is necessary to inject a very high concentration of impurities.

This implantation step is performed under conditions of high vacuum degree in a state in which a resist pattern is formed on a low temperature polysilicon glass substrate on which a low temperature polysilicon film is formed on a glass substrate, but the resist pattern on the substrate is generated by an exothermic action by implantation of impurities. When heated, there is a problem that the resist pattern causes a shape change, or any component in the resist pattern is gasified to lower the vacuum degree in the processing chamber.

As a means to solve this problem, it is effective to perform a heat treatment step called a "post bake" before the implantation step, but the post bake is, for example, 200 ° C or more in a temperature condition close to the temperature heated at the time of implantation. Since it is performed at high temperature, formation of a highly heat resistant resist pattern in which the pattern shape does not change in the heat treatment is essential.

Therefore, in order to realize manufacture of system LCD, it is desired that the heat resistance as a photoresist composition used for it is favorable.

In addition, in the system LCD, for example, the pattern dimension of the display portion is about 2 to 10 µm, whereas the integrated circuit portion is formed to have a fine dimension of about 0.5 to 2.0 µm. Therefore, the photoresist composition for system LCD manufacture not only requires the ability (linearity) to form fine patterns and rough patterns at the same time with good shape, but also has a higher resolution than conventional LCD material resist materials and has a depth of focus of the fine pattern. Good width (DOF) characteristics and the like are strictly required.

However, in the manufacturing field of the liquid crystal element, since the decrease in the sensitivity of the resist material brings about a significant throughput decrease, it is preferable to improve the above characteristics without causing a decrease in the sensitivity.

The gist of the invention

The present invention provides a photoresist composition having satisfactory sensitivity while satisfying heat resistance, resolution, linearity, and DOF characteristics required for the manufacture of a system LCD in which an integrated circuit and a liquid crystal display portion are formed on one substrate. The purpose.

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.

Novolac resin (A-1) in which at least a part of the total phenolic hydroxyl groups is protected by an acid dissociable, dissolution inhibiting group, polyhydroxystyrene resin (A-2) in which at least a part of the total phenolic hydroxyl groups is protected by an acid dissociable, dissolution inhibiting group, And an acid generator (B) which generates an acid by irradiation with radiation in an organic solvent.

In this specification, a "structural unit" represents the monomeric unit which comprises a polymer.

As a value of the mass mean molecular weight (Mw) of solid content of the photoresist composition in this specification, the value measured using the following GPC (gel permeation chromatography) system is used.

Device name: SYSTEM 11 (product name, manufactured by 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), and measured at 280 nm.

Solvent and the like: Measured at 35 ° C by flowing tetrahydrofuran at a flow rate of 1.0 ml / min.

Measurement sample preparation method: The photoresist composition to be measured is adjusted so that solid content concentration will be 30 mass%, this is diluted with tetrahydrofuran, and the measurement sample whose solid content concentration is 0.1 mass% is manufactured. 20 microliters of the measurement sample is injected into the apparatus and measured.

Preferred Embodiment

The chemically amplified positive photoresist composition of the present invention (hereinafter may be simply referred to as a "photoresist composition") is a chemically amplified positive photoresist for producing a substrate in which an integrated circuit and a liquid crystal display portion are formed on one substrate. As a composition, 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, and a polyhydroxystyrene resin in which at least a part of the total phenolic hydroxyl groups is protected with an acid dissociable, dissolution inhibiting group (A- 2) and the acid generator (B) which generate | occur | produce an acid by radiation irradiation are melt | dissolved in the organic solvent.

Hereinafter, the component (A-1) and the component (A-2) may be referred to as a "resin component".

Novolac resin (A-1) in which at least a portion of the total phenolic hydroxyl groups are protected by acid dissociable, dissolution inhibiting groups

In the present invention, the novolak resin (before protection) is obtained by condensation reaction of an aromatic hydroxy compound with aldehydes or ketones 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 condensation reaction of an aromatic compound (aromatic hydroxy compound) having a phenolic hydroxyl group with aldehydes or ketones.

As said aromatic hydroxy compound, it is phenol; cresols such as m-cresol, p-cresol and o-cresol; Xylenols such as 2,3-xylenol, 2,5-xylenol, 3,5-xylenol and 3,4-xylenol; m-ethylphenol, p-ethylphenol, o-ethylphenol, 2,3,5-trimethylphenol, 2,3,5-triethylphenol, 4-tert-butylphenol, 3-tert-butylphenol, 2- alkyl phenols such as tert-butylphenol, 2-tert-butyl-4-methylphenol and 2-tert-butyl-5-methylphenol; alkoxyphenols such as p-methoxyphenol, m-methoxyphenol, p-ethoxyphenol, m-ethoxyphenol, p-propoxyphenol and m-propoxyphenol; isopropenylphenols such as o-isopropenylphenol, p-isopropenylphenol, 2-methyl-4-isopropenylphenol and 2-ethyl-4-isopropenylphenol; Arylphenols such as phenylphenol; And polyhydroxyphenols such as 4,4'-dihydroxybiphenyl, bisphenol A, resorcinol, hydroquinone and pyrogallol. These may be used independently and may be used in combination of 2 or more type.

As the aldehydes, for example, formaldehyde, paraformaldehyde, trioxane, acetaldehyde, propionaldehyde, butylaldehyde, trimethylacetaldehyde, acrolein, crotonaldehyde, cyclohexanealdehyde, furfural, furyl aldehyde, benzaldehyde, benzaldehyde Phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, o -Chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, cinnamic acid aldehyde and the like. These may be used independently and may be used in combination of 2 or more type.

Among these aldehydes, formaldehyde is preferable in view of easy availability. In particular, in order to improve heat resistance, it is preferable to use a combination of hydroxybenzaldehyde and formaldehyde.

As said ketones, acetone, methyl ethyl ketone, diethyl ketone, diphenyl ketone, etc. are mentioned, for example. These may be used independently and may be used in combination of 2 or more type. Furthermore, you may use combining an aldehyde and ketones suitably.

The condensation reaction product of an aromatic hydroxy compound with aldehydes or ketones can be produced by a known method in the presence of an acidic catalyst. At this time, hydrochloric acid, sulfuric acid, formic acid, oxalic acid, paratoluenesulfonic acid, and the like can be used.

At least a part of all the phenolic hydroxyl groups in the component (A-1) are protected with a so-called acid dissociable, dissolution inhibiting group.

An acid dissociable, dissolution inhibiting group (hereinafter sometimes referred to as an "acid dissociating inhibitor") is a process of forming a resist pattern using a photoresist composition, wherein all of the components (A-1) are alkali poorly soluble or alkali insoluble before exposure. It has an alkali dissolution inhibiting property to be set, and after exposure, it dissociates by the action of the acid which generate | occur | produced from the component (B) mentioned later, and changes the whole (A-1) component to alkali solubility.

The novolak resin of component (A-1) shows alkali poor solubility or alkali insolubility in at least a part of all phenolic hydroxyl groups, since the hydrogen atom of the phenolic hydroxyl group is substituted with such an acid dissociable inhibitor, and the acid dissociable inhibitor It exhibits alkali solubility by causing dissociation.

As such an acid dissociable, dissolution inhibiting group, what is necessary is just to dissociate with the acid generate | occur | produced from the component (B) mentioned later, For example, 1-ethoxymethyl group, 1-ethoxyethyl group, 1-propoxymethyl group, 1-prop Alkoxyalkyl groups such as a foxyethyl group, 1-n-butoxymethyl group, 1-iso-butoxymethyl group, and 1-tert-butoxymethyl group; alkoxycarbonylalkyl groups such as t-butoxycarbonyl group, t-butoxycarbonylmethyl group and t-butoxycarbonylethyl group; Tetrahydrofuranyl group; Tetrahydropyranyl group; Linear or branched acetal groups; Cyclic acetal groups; Trialkyl silyl groups, such as a trimethylsilyl group, a triethyl silyl group, and a triphenyl silyl group, are mentioned.

In particular, the ethyl vinyl group (ethoxyethyl group) represented by the following general formula (IV-1) and the t-butoxycarbonyl group represented by the following general formula (IV-2) are used to obtain a photoresist composition excellent in resolution. It is preferable and ethyl vinyl group is especially preferable.

[Formula IV-1]

[Formula IV-2]

The preferable range of the mass average molecular weight (Mw) of the novolak resin before being protected with an acid dissociable, dissolution inhibiting group is 1000 to 200000, preferably 2000 to 50000, and more preferably 3000 to 30000. If Mw of (A-1) component is more than the said lower limit, the tendency which a resolution may fall can be suppressed, and if it is below the said upper limit, the applicability | paintability of a photoresist composition can be prevented.

Polyhydroxystyrene resins (A-2) in which at least a portion of the total phenolic hydroxyl groups are protected by acid dissociable, dissolution inhibiting groups

In the present invention, polyhydroxy styrene (before protection) is a concept including a polymer (hydroxy styrene homopolymer) and derivatives thereof composed of hydroxy styrene. As such polyhydroxy styrene, the homopolymer of vinylphenol, the copolymer of vinylphenol, and the comonomer copolymerizable with this, etc. are mentioned, for example. Here as comonomer, for example, acrylic acid derivative, acrylonitrile, methacrylic acid derivative, methacrylonitrile, styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, p-methoxystyrene, p-chloro Styrene derivatives, such as styrene, are mentioned. Among the polyhydroxystyrenes, hydroxystyrene homopolymers, hydroxystyrene-styrene copolymers, and the like are preferable.

The polyhydroxy styrene resin of the component (A-2) is also alkali, because, in the same manner as the component (A-1), the hydrogen atom of the phenolic hydroxyl group is substituted with an acid dissociable inhibitor in at least a part of all the phenolic hydroxyl groups. What is necessary is just to show poor solubility or alkali insolubility, and to be alkali-soluble by dissociating the acid dissociation inhibitor from a phenolic hydroxyl group.

Such a component (A-2) is obtained by reacting the polyhydroxystyrene resin (polyhydroxystyrene resin before protection) which does not have an acid dissociable, dissolution inhibiting group, and the compound corresponded to an acid dissociable, dissolution inhibiting group.

In addition, the said hydroxy styrene shall also include the derivative (s). Specifically, the hydroxystyrene structural unit is represented by the following general formula (II).

[Formula II]

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

R <_0> is a hydrogen atom or a lower alkyl group (for example, C1-C5 (linear or branched may be sufficient), Preferably it is a methyl group), Preferably it is a hydrogen atom. The position of the hydroxyl group can be any of o-, m-, and p-positions, but the p-position is preferred in view of its readily available and low cost.

In the hydroxystyrene-styrene copolymer, styrene also 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 which are substituents is 1-3.

As an acid dissociable, dissolution inhibiting group in (A-2) component, it is good to dissociate with the acid generate | occur | produced from (B) component mentioned later similarly to the acid dissociable, dissolution inhibiting group in above-mentioned (A-1) component. . Examples, preferable examples, and the like of an acid dissociable, dissolution inhibiting group are the same as those described in the description of the component (A-1).

The preferable range of the mass mean 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, and more preferably 3000 to 30000. If Mw of polyhydroxy styrene resin is more than the said lower limit, the tendency which a resolution may fall can be suppressed, and if it is below the said upper limit, the applicability | paintability of a photoresist composition can be prevented from worsening.

Since the positive photoresist composition of the present invention exhibits a chemically amplified mechanism, the development contrast of the unexposed portion and the exposed portion is strong, and as the resin component, both of the component (A-1) and the component (A-2) By including these, good heat resistance, resolution, linearity and DOF characteristics can be expressed.

As for the resolution, the resolution in the low NA condition is particularly high.

For example, at a low NA condition of NA = 0.14, it has a resolution of the minimum dimension 1.1-1.0 μm line and space (L & S). In terms of heat resistance, for example, even if the resist pattern formed using the 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.

It is preferable that the content rate of (A-1) component and (A-2) component in the photoresist composition of this invention is (A-1) / (A-2) = 0.1 / 1-10/1 by mass ratio. Do. When the content ratio is within this range, a good resolution (for example, about 1.1 to 1.0 µm L & S at low NA) can be particularly stably realized at low NA conditions, and the resist having excellent heat resistance, linearity, and DOF characteristics is very stable. The pattern can be formed.

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 this invention, although the well-known resin component used in the resist composition other than (A-1) component and (A-2) component can also be mix | blended, Preferably it is a (A-1) component and 70 mass% or more is preferable in all the resin components, the total amount of (A-2) component is more preferable, 80 mass% or more is more preferable, and it is most preferable that it is 100 mass%.

Acid generator which generates acid by exposure (B)

The component (B) is not particularly limited, and a photoacid generator conventionally known as a material of a chemically amplified positive photoresist composition, for example, a sulfonyldiazomethane-based acid generator, an onium salt-based acid generator, and jade Simsulfonate type acid generator etc. can be used.

In particular, in the manufacture of LCDs, ultraviolet rays in which g-rays, h-rays, and i-rays coexist are sometimes used. As the component (B), a compound having a high acid generation efficiency when such ultraviolet rays are irradiated is preferable. In order to improve the resolution, i-line having a short wavelength is preferably used, and i-line tends to be used mainly in the manufacture of system LCDs, and thus, as the component (B), acid is generated by irradiation of i-line in particular. It is preferable that it is a compound, and the compound with high acid generation efficiency with respect to i line | wire exposure is especially preferable.

As the component (B), for example, the following compounds are preferably used in view of high acid generation efficiency with respect to i-ray exposure.

Represented by the following formulas (V) and (VI):

[Formula V]

[Formula VI]

(Wherein m 'is 0 or 1; X is 1 or 2; R ₁ is a phenyl group, heteroaryl group, etc., in which one or more C1-C12 alkyl groups may be substituted, or m' is 0) C2-C6 alkoxycarbonyl group, phenoxycarbonyl group, CN, etc .; R ₁ 'means C2-C12 alkylene group, R ₂ means the same as R ₁ , etc. R ₃ means C1-C18 alkyl group, etc .; R ₃ ' is X = 1 be of the same meaning as R ₃ as such, X = 2 days when C2-C12 alkylene group, phenylene group, etc.; R _4, R ₅ are independently a hydrogen atom, a halogen, such as C1-C6 alkyl group; a is S, O, NR ₆ and the like; R ₆ represents a hydrogen atom, a phenyl group or the like) (USP 6004724). Specifically, the thioene containing oxime sulfonate etc. which are represented by following formula (VII) are mentioned, for example:

[Formula VII]

Moreover, following formula (VIII)

[Formula VIII]

(In formula, R <^6> , R <^7> represents a C1-C3 alkyl group, respectively.) Or the bis (trichloromethyl) triazine compound represented by this, or its compound (VIII), and following formula (IX)

[Formula IX]

In which the bis (trichloromethyl) triazine compound represented by (wherein Z represents a 4-alkoxyphenyl group or the like) is combined (JP-A-6-289614, JP-A 7-134412) ).

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 (trichloro Methyl) -1,3,5-triazine, 2- [2- (3-ethoxy-4-propoxyphenyl) 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) -1,3,5-triazine and the like. These triazine compounds may be used independently and may be used in combination of 2 or more type.

In addition, as said triazine compound (IX) which can be used in combination with the said triazine compound (VIII) as needed, 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-propoxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-butoxynaph Tyl) -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) Nil] -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 (trichloromethyl) -1,3,5-triazine, 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-pro Foxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy-5-methoxyphenyl) ethenyl] -4, 6-bis (trickle) Rhomethyl) -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-methylene Dioxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-methylenedioxyphenyl) ethenyl] -4,6-bis ( Trichloromethyl) -1,3,5-triazine and the like. 1 type of these triazine compounds may be used, and may be used in combination of 2 or more type.

Moreover, following formula (X)

[Formula X]

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

Formula XI

(B) A component can be used 1 type or in mixture of 2 or more types.

The compounding quantity of (B) component becomes like this. Preferably it is 1-30 mass parts, More preferably, it is 1-10 mass parts with respect to a total of 100 mass parts of (A-1) component and (A-2) component.

Basic compound (C)

In the photoresist composition of this invention, in order to improve an inch stability, it is preferable to mix | blend a basic compound (preferably amines) as (C) component.

What is necessary is just to have compatibility with a photoresist composition as this compound, Although it does not restrict | limit especially, For example, the compound of Unexamined-Japanese-Patent No. 9-6001 is mentioned.

In particular, by blending a relatively bulky specific basic compound (c1) represented by the following general formula (I), there is also an effect of suppressing the amount of acid components generated in the resist composition over time, and the long-term storage stability of the resist composition Can improve.

[Formula I]

In the formula (I), at least one of X, Y, and Z (preferably at least 2, most preferably three) is the following (1) to (4): (1) an alkyl group having 4 or more carbon atoms, (2) carbon atoms It is group chosen from three or more cycloalkyl groups, (3) phenyl group, and (4) aralkyl group.

In addition, among said X, Y, Z, what is not said (1)-(4) is a group or atom chosen from the (1 ') C3 or less alkyl group and (2') hydrogen atom.

X, Y, and Z may be the same as or different from each other, but when two or more of X, Y, and Z are selected from (1) to (4), the groups corresponding to these are the same. It is preferable from a stability viewpoint.

(1) an alkyl group having 4 or more carbon atoms

In the case of said (1), when carbon number is less than 4, it is difficult to improve stability with time. Carbon number is more preferably 5 or more, particularly preferably 8 or more. Although an upper limit is not specifically limited, 20 or less are preferable and 15 or less are especially preferable at the point which a stabilization effect with time is observed, and it is easy to obtain commercially. Moreover, when it exceeds 20, basic strength will weaken and the effect of storage stability will fall.

The alkyl group may be either linear or branched.

Specifically, n-decyl group, n-octyl group, n-pentyl group, etc. are preferable, for example.

(2) A cycloalkyl group having 3 or more carbon atoms

In the cycloalkyl group, a cycloalkyl group having 4 to 8 carbon atoms is particularly commercially available and is preferable because of its excellent effect of improving stability over time. In particular, a cyclohexyl group having 6 carbon atoms is preferable.

(4) Aralkyl groups

The aralkyl group is represented by the formula: -R'-P (R 'is an alkylene group, P is an aromatic hydrocarbon group).

Although P, a naphthyl group, etc. are mentioned as P, A phenyl group is preferable.

Carbon number of R 'should just be 1 or more, Preferably it is 1-3.

As an aralkyl group, a benzyl group, a phenylethyl group, etc. are preferable, for example.

Moreover, among X, Y, and Z, what is not said (1)-(4) is group or atom chosen from said (1 ') and (2').

(1 ') may be either a straight chain or a branched chain. Especially methyl group and ethyl group are preferable.

As (c1) component, it is preferable to comprise a tertiary amine. That is, it is preferable that what is not said (1)-(4) among X, Y, Z is 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. Can be mentioned.

Especially, 1 or more types chosen from tri-n-decylamine, methyl-di-n-octylamine, and tri-n-pentylamine are preferable, and tri-n-decylamine is especially preferable.

(C) component can be used 1 type or in mixture of 2 or more types.

0.01-5.0 mass parts is preferable with respect to a total of 100 mass parts of said (A-1) component and (A-2) component, and (C) component is especially preferable to mix | blend in the range of 0.1-1.0 mass part from a viewpoint of an effect. Do.

Organic solvent

As an organic solvent in the photoresist composition of this invention, if it is used for the positive type photoresist composition of a chemical amplification type, it can be used, without particular limitation.

As an organic solvent, an ester solvent and a nonester solvent are mentioned, for example.

Examples of the ester solvents 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.

Acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, 2-heptanone etc. are mentioned as ketones. Examples of the polyhydric alcohols and derivatives thereof include ethylene glycol, propylene glycol, diethylene glycol, monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, monophenyl ether, and the like thereof. Dioxane etc. are illustrated as cyclic ethers.

Moreover, since an ester solvent is a reaction product of organic carboxylic acid and alcohol, it contains the organic carboxylic acid which is a free acid.

Therefore, in the resist composition which does not mix | blend the said (c1) component, or the resist composition which does not mix | blend the storage stabilizer mentioned later, it is preferable to select the non-ester solvent which does not contain such a free acid, and especially ketones (ketone system) Solvent) is preferred. Especially, 2-heptanone is preferable also from a coating-film viewpoint.

In addition, the ester solvent and the non-ester solvent may be decomposed over time to produce an acid, but the decomposition reaction is suppressed in the presence of the component (c1) or in the presence of a storage stabilizer described later. . Especially in ester solvent, the effect is remarkable, ester solvent is rather preferable in presence of the said (c1) component and a storage stabilizer, and propylene glycol monoalkyl ether acetates, such as PGMEA, are especially preferable.

Moreover, as an acid component by-product produced by the said decomposition, for example, in the case of 2-heptanone, it is confirmed to generate formic acid, acetic acid, propionic acid, etc.

The organic solvent can be used 1 type or in mixture of 2 or more types.

In the photoresist composition of the present invention, it is preferable that 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 secure coating properties. Do.

In addition, it is preferable to mix | blend the following storage stabilizers with the chemically amplified positive photoresist composition of this invention as needed.

The storage stabilizer is not particularly limited as long as it has an action of inhibiting the decomposition reaction of the solvent, and examples thereof include antioxidants as described in JP-A-58-194834. Phenolic compounds and amine compounds are known as antioxidants. Especially, phenolic compounds are preferable, and among these, 2,6-di (tert-butyl) -p-cresol and its derivatives are ester solvents and ketone solvents. It is preferable in terms of being effective against degradation, commercially available, inexpensive, and excellent in storage stability effect. In particular, the effect of preventing deterioration of propylene glycol monoalkyl ether acetate and 2-heptanone is very excellent.

As for the compounding quantity of the said storage stabilizer, 0.01-3 mass parts is preferable with respect to 100 mass parts of the sum total of (A-1) component and (A-2) component, and it is especially preferable that it is the range of 0.1-1.0 mass part.

In addition, the photoresist composition of the present invention may contain additives, plasticizers, stabilizers, and surfactants for improving the performance of a compatible additive, for example, the performance of a resist film, if necessary, within a range that does not impair the object of the present invention. And conventional additives such as a coloring agent for making the developed image more visible, a sensitizer for improving the sensitizing effect, a dye for preventing halation, and an adhesion improving agent.

It is preferable that the mass mean molecular weight (Mw) of the solid content of the photoresist composition of this invention is 3000-100000, and it is more preferable that it is 5000-50000. When Mw of a photoresist composition is 3000-100000, a photoresist composition becomes more excellent regarding high heat resistance, high resolution, and depth of focus characteristic (DOF characteristic). In addition, solid content of a positive photoresist composition is the sum total of (A-1), (A-2), (B) component and the other component used as desired.

The positive photoresist composition of the present invention can be produced by dissolving the component (A-1), the component (A-2), the component (B), and other components in an organic solvent as desired.

The amount of the organic solvent used is preferably adjusted so as to obtain a uniform positive photoresist composition when dissolving the (A-1), (A-2) and (B) components and other components used as desired. do. Preferably it is used so that solid content concentration may be 10-50 mass%, More preferably, it is 20-35 mass%.

As a method of adjusting the Mw of solid content of a photoresist composition so that it may become the said preferable range, for example, (1) component before mixing so that Mw after mixing all the components may become the said range, and A method of fractionating a component (A-2) to adjust the Mw of the resin component to an appropriate range in advance, and (2) a plurality of components (A-1) or (A-2) having different Mw are prepared. And it mix | blends this suitably and the method of adjusting Mw of the solid content to the said range, etc. are mentioned.

Among these preparation methods, especially the preparation method by said (2) is more preferable at the point which the adjustment of a resist molecular weight and the sensitivity adjustment are easy.

(Formation method of resist pattern)

Below, a preferable example of the method of manufacturing system LCD using the photoresist composition of this invention is shown.

First, the photoresist composition of this invention is apply | coated to a board | substrate with a spinner etc., and a coating film is formed.

As a board | substrate, the glass substrate in which the silicon film was formed is preferable. Amorphous silica is usually used in the formation of the silicon film, but low-temperature polysilicon and the like are known to be preferable in the field of system LCDs. In addition, a large substrate of 300 mm × 400 mm or more, particularly 550 mm × 650 mm or more can be used.

Subsequently, the board | substrate with which this coating film was formed is heat-processed (prebaked) at 90-140 degreeC, for example, a residual solvent is removed and a resist film is formed. As a prebaking method, it is preferable to perform a proximity baking which makes the clearance gap between a hotplate and a board | substrate.

Subsequently, selective exposure is performed to the said resist film using the mask in which both the mask pattern for integrated circuits and the mask pattern for liquid crystal display parts were drawn.

As a light source used here, in order to form a fine pattern, it is preferable to use i line | wire (365 nm). In addition, it is preferable that the exposure process employ | adopted by this exposure is an exposure process of low NA conditions of NA or less, Preferably it is 0.2 or less, More preferably, it is 0.15 or less. By employing an exposure process in a low NA condition, one exposure area can be widened, and throughput can be improved.

Next, heat treatment (post exposure bake: PEB) is performed on the resist film after selective exposure. Examples of the PEB method include a proximal bake having a gap between the hot plate and the substrate and a direct bake without a gap. The PEB method is performed by performing a proximal bake in order to prevent the substrate from bending and to obtain a diffusion effect by the PEB. Then, the method of performing direct baking is preferable. Moreover, 90-150 degreeC is preferable and 100-140 degreeC of heating temperature is especially preferable.

When the development process using the developing solution, for example, alkaline aqueous solution, such as 1-10 mass% tetramethylammonium hydroxide (TMAH) aqueous solution, is performed with respect to the resist film after the said PEB, an exposure part will melt | dissolve and remove it on a board | substrate. A resist pattern for the integrated circuit and a resist pattern for the liquid crystal display portion are formed at the same time.

Subsequently, the resist pattern can be formed by washing the developer remaining on the surface of the resist pattern with a rinse solution such as pure water.

In the step of performing the selective exposure, it is preferable to use a mask on which both a resist pattern forming mask pattern of 2.0 µm or less and a mask pattern for forming resist pattern of more than 2.0 µm are drawn.

Since the chemically amplified positive photoresist composition of the present invention is excellent in linearity, a resist pattern that faithfully reproduces both the rough pattern and the fine pattern of the mask pattern is obtained. Therefore, the resist pattern for integrated circuits with a pattern dimension of 2.0 micrometers or less, and the resist pattern for liquid crystal display parts larger than 2.0 micrometers can be simultaneously formed on a board | substrate.

Example

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

[Evaluation Method of Positive Photoresist Composition]

The evaluation method of the following general physical properties (1)-(5) is shown below about the positive photoresist composition of the following Example or a comparative example.

(1) Sensitivity evaluation: After apply | coating positive type photoresist composition on the glass substrate (550 mm x 650 mm) in which Ti film was formed using the resist coating apparatus for large substrates (apparatus name: TR36000 TOKYO OKA CO., LTD.) , Prebaking was carried out by proximal bake at intervals of about 1 mm under heating conditions of 90 ° C. and 90 seconds to form a resist film having a thickness of 1.5 μm.

Subsequently, the i-ray exposure apparatus (device name: FX-702J, manufactured by Nikon Corporation) was used through a test chart mask (reticle) on which a resist pattern of 1.5 μm L & S and a mask pattern for reproducing a resist pattern of 3.0 μm L & S were simultaneously drawn. ), Selective exposure was performed at an exposure amount (Eop exposure amount) that can faithfully reproduce 1.5 µm L & S.

Subsequently, PEB was performed by proximity breach with the space | interval of 0.5 mm on the conditions of 110 degreeC and 90 second.

Subsequently, after developing for 90 seconds using 23 degreeC and 2.38 mass% TMAH aqueous solution, it rinsed with pure water for 30 second and spin-dried.

As an index of sensitivity evaluation, the exposure amount (Eop, unit: mJ) which can faithfully reproduce the resist pattern of 1.5 micrometers L & S was used.

(2) DOF characteristic evaluation: In the said Eop exposure amount, the focal point was shifted up and down suitably, and the width | variety of the depth of focus (DOF) obtained in the range of the dimensional change rate whose 1.5 micrometer L & S is +/- 10% was calculated | required.

(3) Heat resistance evaluation: The cross-sectional shape was observed after leaving the board | substrate with 1.5 micrometers L & S in the said Eop exposure amount on the hotplate set to 200 degreeC for 30 minutes. As a result, the thing which exceeded (triangle | delta) and +/- 5% of what was in (circle), 3 to 5%, or -5 to -3% of thing that the bottom dimension change rate of 1.5 micrometers L & S was within ± 3% was represented by x.

(4) Resolution evaluation: The limit resolution in the said Eop exposure amount was calculated | required.

(5) Linearity evaluation: The cross-sectional shape of the resist pattern of 3.0 micrometers L & S obtained by the said Eop exposure amount was observed with the SEM (scanning electron microscope) photograph, and the reproducibility of the resist pattern of 3.0 micrometers L & S was evaluated. The dimensional change rate of 3.0 µm L & S was within ± 10%, and the one exceeding ± 10% was indicated by ×.

Hereinafter, all the "mass average molecular weight" show the polystyrene conversion mass average molecular weight by gel permeation chromatography.

In the following examples, the following were used as the component (A-1).

(A-1) component

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 / salicyaldehyde = 3/1 as a condensing agent. What refine | purified the alkali-soluble novolak resin of the 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 the acid aqueous solution.

The reprecipitation method was performed by dissolving the resin in a 30% by mass aqueous methanol solution, adding pure water thereto to precipitate the resin.

In addition, the washing process by the said acid aqueous solution was performed by wash | cleaning the said precipitated resin once with the hydrochloric acid aqueous solution and twice with pure water.

In addition, the following were used as a component (A-2).

(A-2) component

Polyhydroxystyrene resin in which 30 to 40% of all phenolic hydroxyl groups were protected with 1-ethoxyethyl group.

In addition, 20000 of Mw of polyhydroxy styrene resin before protecting with 1-ethoxyethyl group was used.

(Example 1)

Component (A-1) (Mw: 5000 before being protected with an acid dissociable, dissolution inhibiting group): 33 parts by mass

17 mass parts of said (A-2) component (Mw: 20000 before being protected by the acid dissociable, dissolution inhibiting group)

(B) component [compound of said Formula (XI)]: 3 mass parts

(C) component [tri-n-decylamine]: 0.2 mass part

The above various components were dissolved in PGMEA, and 500 ppm of XR-104 (trade name; manufactured by Dainippon Ink Industries Co., Ltd.) as a surfactant was adjusted to a solution having a concentration of 35% by mass, and this was a membrane filter having a pore diameter of 0.2 µm. Filtration was carried out to prepare a photoresist composition.

About this photoresist composition, the physical property of said (1)-(5) was evaluated. The results are shown in Table 1 below.

(Example 2)

In Example 1, except for changing the compounding quantity of the said (A-1) component from 33 mass parts to 25 mass parts, and changing the compounding quantity of (A-2) component from 17 mass parts to 25 mass parts, In the same manner, a photoresist composition was prepared. About this photoresist composition, the physical property of said (1)-(5) was evaluated. The results are shown in Table 1 below.

(Example 3)

In Example 1, except for changing the compounding quantity of the said (A-1) component from 33 mass parts to 17 mass parts, and changing the compounding quantity of (A-2) component from 17 mass parts to 33 mass parts, In the same manner, a photoresist composition was prepared. About this photoresist composition, the physical property of said (1)-(5) was evaluated. The results are shown in Table 1 below.

(Comparative Example 1)

In Example 1, except for changing the compounding quantity of the said (A-1) component from 33 mass parts to 50 mass parts, and changing the compounding quantity of (A-2) component from 17 mass parts to 0 mass part, In the same manner, a photoresist composition was prepared. About this photoresist composition, the physical property of said (1)-(5) was evaluated. The results are shown in Table 1 below.

(Comparative Example 2)

In Example 1, except for changing the compounding quantity of the said (A-1) component from 33 mass parts to 0 mass part, and changing the compounding quantity of (A-2) component from 17 mass parts to 50 mass parts, In the same manner, a photoresist composition was prepared. About this photoresist composition, the physical property of said (1)-(5) was evaluated. The results are shown in Table 1 below.

Sensitivity (mJ) DOF (μm) Heat resistance Resolution (μm) Linearity Example 1 26 ＞ 30 ○ 1.1 ○ Example 2 24 ＞ 30 ○ 1.1 ○ Example 3 22 ＞ 30 ○ 1.1 ○ Comparative Example 1 30 25 △ 1.2 × Comparative Example 2 20 ＞ 30 × 1.0 ×

From Table 1, in the Example concerning this invention, the sensitivity, DOF characteristic, heat resistance, resolution, and linearity were all favorable, and it turned out that it is preferable for system LCD manufacture. On the other hand, in Comparative Example 1, in which the polyhydroxystyrene resin was not used, all of the sensitivity, DOF characteristics, heat resistance, resolution, and linearity were all Examples, in Comparative Example 2, in which the novolak resin was not used, the heat resistance and linearity were each Example It was inferior and insufficient for producing system LCDs.

Since the chemically amplified positive photoresist composition of the present invention has good sensitivity, excellent heat resistance, and high resolution is obtained, it is preferable for system LCD manufacture, and throughput can be improved.

Moreover, since linearity is excellent, a rough pattern and a fine pattern can be formed on one board | substrate under the same exposure conditions. Therefore, the display portion of the system LCD and the resist pattern of the finer integrated circuit portion can also be obtained at a high resolution at the same time, which is preferable for system LCD manufacture.

In addition, in the positive type photoresist composition for system LCD manufacture, it is important that the width of the depth of focus is somewhat large from the viewpoint of manufacturing efficiency, controllability of manufacturing conditions, etc., but the chemically amplified positive type photoresist of the present invention. The composition can realize a width of depth of focus (eg, 15 μm or greater) that is practical for system LCDs.

As mentioned above, although preferable Example of this invention was described, this invention is not limited to these Examples. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the invention. The invention is not limited by the foregoing description, but only by the scope of the appended claims.

Claims (7)

A chemically amplified positive photoresist composition for manufacturing a substrate having an integrated circuit and a liquid crystal display portion formed on one substrate, Novolac resin (A-1) in which at least a part of the total phenolic hydroxyl groups is protected by an acid dissociable, dissolution inhibiting group, polyhydroxystyrene resin (A-2) in which at least a part of the total phenolic hydroxyl groups is protected by an acid dissociable, dissolution inhibiting group, And an acid generator (B) that generates an acid by irradiation with radiation in an organic solvent. A chemically amplified positive photoresist composition. The chemically amplified positive type according to claim 1, wherein the content ratio of the component (A-1) and the component (A-2) is (A-1) / (A-2) = 0.1 / 1 to 10/1 by mass ratio. Type photoresist composition. The chemically amplified positive photoresist composition according to claim 1 or 2, further comprising a basic compound (C). 4. The chemically amplified positive photoresist composition according to claim 3, wherein the component (C) contains a compound (c1) represented by the following general formula (I): [Formula I]

[In formula, one or more of X, Y, Z is group chosen from following (1)-(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, Among the said X, Y, Z, what is not said (1)-(4) is group or atom chosen from the following: (1 ') an alkyl group having 3 or less carbon atoms, (2 ') hydrogen atom]. The chemically amplified positive photoresist composition according to claim 3, wherein the content of the component (C) is 0.01 to 5.0 parts by mass based on 100 parts by mass of the total of the components (A-1) and (A-2). The chemically amplified positive photoresist composition according to claim 1 or 2, wherein the component (B) is a compound that generates an acid by irradiation with i-rays (365 nm wavelength). The chemically amplified positive photoresist composition according to claim 1 or 2, wherein the organic solvent contains at least one selected from propylene glycol monoalkyl ether acetate and 2-heptanone.