JP2008250062A - Chemically amplified positive photoresist composition for thick film and method for manufacturing thick film resist pattern - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chemically amplified positive photoresist composition for a thick film from which a favorable resist pattern having high resolution can be obtained even on a support having a part made of copper on its surface, and to provide a method for manufacturing a thick film resist pattern. <P>SOLUTION: The chemically amplified positive photoresist composition for a thick film is to be used to form a thick film photoresist layer having a film thickness of 0.1 to 100 μm on a support, and the composition contains an acid generator such as an onium salt having an anionic moiety in a specified structure and a resin having a specified structural unit in a specified compounding ratio. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a chemically amplified positive photoresist composition for thick film and a method for producing a thick film resist pattern. More specifically, the present invention relates to circuit board manufacture, CSP (chip size package) to be mounted on the circuit board, micro electro mechanical system (MEMS) element, small machine (MEMO machine) incorporating the MEMS element, and high-density mounting. Thick film chemically amplified positive photoresist composition and thick film resist pattern which are suitably used for forming connection terminals such as bumps and metal posts, coils and wiring patterns in the manufacture of electronic parts such as through electrodes It is related with the manufacturing method.

  Photofabrication, which is currently the mainstream of precision microfabrication technology, is the application of a photosensitive resin composition to the surface of a workpiece to form a coating film, which is then patterned using photolithography technology. A general term for technologies for manufacturing various precision parts such as semiconductor packages by performing chemical forming, electrolytic etching, and / or electroforming mainly composed of electroplating as a mask.

  In recent years, with the downsizing of electronic equipment, high-density packaging technology for semiconductor packages has progressed. Based on multi-pin thin film packaging of packages, miniaturization of package size, flip-chip two-dimensional packaging technology, and three-dimensional packaging technology. The packaging density is improved. In such a high-density mounting technology, as connection terminals, for example, protruding electrodes (mounting terminals) such as bumps protruding on the package, or metal posts that connect the rewirings extending from the peripheral terminals on the wafer and the mounting terminals. Are arranged with high accuracy on the substrate.

  There is a thick film photoresist as a material used for the above photofabrication. The thick film photoresist forms a thick film photoresist layer, and is used, for example, for forming bumps and metal posts by a plating process. For bumps and metal posts, for example, a thick photoresist layer with a film thickness of about 20 μm is formed on a support, exposed through a predetermined mask pattern, developed, and a portion where bumps and metal posts are formed is selective. The resist pattern removed (peeled) is formed, and a conductor such as copper is embedded in the removed portion (non-resist portion) by plating, and then the resist pattern around the resist pattern is removed. .

Examples of the thick film photoresist include a chemically amplified photoresist containing an acid generator, which is known as a photosensitive resin composition having higher sensitivity. The feature of chemically amplified photoresist is that acid is generated from the acid generator by radiation irradiation (exposure), and the diffusion of the acid is promoted by the heat treatment after the exposure, and the acid catalyst for the base resin in the resin composition. The reaction is caused to change the alkali solubility (see, for example, Patent Documents 1 to 3).
JP 2004-012554 A JP 2004-085657 A JP 2005-173464 A

  By the way, the thick photoresist layer may be formed on a support having a portion formed of copper on the upper surface, for example, a copper substrate. However, if a thick photoresist layer is formed on the copper substrate, the influence of copper is present. Therefore, there is a problem that a good resist pattern cannot be obtained.

  On the other hand, with the high integration and miniaturization of electronic equipment, there has been a demand for a chemically amplified positive photoresist composition for thick film having higher resolution. For example, with the increase in capacity and miniaturization of hard disks, there has been a demand for finer copper coils attached to the tip of the magnetic head of the hard disk. For this reason, there has been a demand for a method of manufacturing a thick film resist pattern capable of finely processing such copper coils, connection terminals, wiring patterns, and the like.

  The present invention has been made in view of the above problems, and has a high resolution on a support having a portion formed of copper on the upper surface, and a thick film capable of obtaining a good resist pattern. It is an object of the present invention to provide a chemically amplified positive photoresist composition and a method for producing a thick film resist pattern.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors include an acid generator such as an onium salt having an anion portion having a specific structure, and a resin having a specific structural unit at a specific blending ratio. The thick film chemically amplified positive photoresist composition has been found to solve the above problems, and has completed the present invention. Specifically, the present invention provides the following.

［化学式（ａ１）中、Ｘ、Ｙ、及びＺは、それぞれ独立に、少なくとも１つの水素原子がフッ素原子で置換された炭素数１〜１０のアルキル基を示す。］

［化学式（ｂ３）中、Ｒ^１は水素原子又はメチル基を表す。Ｒ^２は酸解離性溶解抑制基を表す。ｌは５０〜８０、ｍは３〜２０、ｎは２０〜３０である。］ A first aspect of the present invention is a thick film chemically amplified positive photoresist composition used for forming a thick film photoresist layer having a film thickness of 0.1 to 100 μm on a support, comprising (A) A compound that generates an acid upon irradiation with actinic rays or radiation, and (B) a resin whose solubility in alkali is increased by the action of the acid, wherein the component (A) is represented by the following chemical formula (a1) The component (B) is a structural unit represented by the following chemical formula (b1), a structural unit represented by the following chemical formula (b2), and a structural unit represented by the following chemical formula (b3) A chemically amplified positive photoresist composition for thick films, characterized in that it is a copolymer having

[In the chemical formula (a1), X, Y, and Z each independently represent an alkyl group having 1 to 10 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom. ]

[In the chemical formula (b3), R ¹ represents a hydrogen atom or a methyl group. R ² represents an acid dissociable, dissolution inhibiting group. l is 50 to 80, m is 3 to 20, and n is 20 to 30. ]

  In the second aspect of the present invention, a support and a thick photoresist layer having a film thickness of 0.1 to 100 μm made of the chemically amplified positive photoresist composition for thick film of the first aspect of the present invention are laminated. Laminating step of obtaining a thick film photoresist laminate, an exposure step of selectively irradiating the thick film photoresist laminate with actinic rays or radiation, a developing step of developing after the exposing step to obtain a thick film resist pattern, A method for producing a thick film resist pattern.

  According to the present invention, even on a support having a portion formed of copper on its upper surface, for example, a copper substrate, it has high resolution and a wide Focus margin can be obtained when irradiated with actinic rays or radiation. A good thick film resist pattern can be formed.

  Hereinafter, embodiments of the present invention will be described in detail.

  The chemically amplified positive photoresist composition for thick film of the present invention has increased solubility in alkali due to the action of (A) a compound that generates an acid upon irradiation with active light or radiation, and (B) the action of the acid as described later. Contains resin.

<(A) Compound that generates acid upon irradiation with active light or radiation>
The compound (A) that generates an acid upon irradiation with actinic rays or radiation (hereinafter referred to as component (A)) used in the chemically amplified positive photoresist composition for thick film of the present invention is an acid generator, Generates acid.

（化学式（ａ１）中、Ｘ、Ｙ、及びＺは、それぞれ独立に、少なくとも１つの水素原子がフッ素原子で置換された炭素数１〜１０のアルキル基を示す。） Specifically, the anion portion of the component (A) used in the chemically amplified positive photoresist composition for thick film of the present invention is represented by the following chemical formula (a1).

(In the chemical formula (a1), X, Y, and Z each independently represent an alkyl group having 1 to 10 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom.)

  In the anion moiety of the component (A) represented by the chemical formula (b1), X, Y, and Z each independently represent an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom. The alkyl group has 1 to 10 carbon atoms, preferably 1 to 7 carbon atoms, and more preferably 1 to 3 carbon atoms. Specific examples of the alkyl group include linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl and octyl; branched alkyl groups such as isopropyl, isobutyl, sec-butyl and tert-butyl; and cyclopropyl, cyclobutyl and cyclopentyl. The ratio of the hydrogen atom of the alkyl group substituted by a fluorine atom is preferably 50% or more, more preferably 80% or more, and most preferably 100%. When the substitution rate of fluorine atoms is less than 50%, the acid strength of the onium salt represented by the chemical formula (a1) decreases.

Particularly preferred X, Y, and Z are linear or branched perfluoroalkyl groups having 1 to 3 carbon atoms and a fluorine atom substitution rate of 100%. Specific examples include CF ₃ , CF _{3 CF 2, (CF 3)} 2 CF, include _CF 3 CF ₂ CF 2. Among them, it is most preferable that X, Y, and Z are all CF ₃ groups. By making all of X, Y, and Z a CF ₃ group having a strong electron-withdrawing property, the stability of the carbanion can be further increased.

（化学式（ａ２）中、Ａは原子価ｍの硫黄原子又はヨウ素原子を表し、ｍは１又は２である。ｎは括弧内の構造の繰り返し単位数を表し、０〜３の整数である。ＲはＡに結合している有機基であり、炭素数６〜３０のアリール基、炭素数４〜３０の複素環基、炭素数１〜３０のアルキル基、炭素数２〜３０のアルケニル基、又は炭素数２〜３０のアルキニル基を表し、Ｒはアルキル、ヒドロキシ、アルコシキ、アルキルカルボニル、アリールカルボニル、アルコシキカルボニル、アリールオキシカルボニル、アリールチオカルボニル、アシロキシ、アリールチオ、アルキルチオ、アリール、複素環、アリールオキシ、アルキルスルフィニル、アリールスルフィニル、アルキルスルホニル、アリールスルホニル、アルキレンオキシ、アミノ、シアノ、ニトロの各基、及びハロゲンからなる群より選ばれる少なくとも１種で置換されていてもよい。Ｒの個数はｍ＋ｎ（ｍ−１）＋１であり、Ｒはそれぞれ互いに同じであっても異なっていてもよい。また、２個以上のＲが互いに直接、又は−Ｏ−、−Ｓ−、−ＳＯ−、−ＳＯ_２−、−ＮＨ−、−ＮＲ’−、−ＣＯ−、−ＣＯＯ−、−ＣＯＮＨ−、炭素数１〜３のアルキレン基若しくはフェニレン基を介して結合し、Ａを含む環構造を形成してもよい。Ｒ’は炭素数１〜５のアルキル基又は炭素数６〜１０のアリール基である。
Ｄは下記化学式（ａ３）で表される構造であり、

化学式（ａ３）中、Ｅは炭素数１〜８のアルキレン基、炭素数６〜２０のアリーレン基、又は炭素数８〜２０の複素環化合物の２価の基を表し、Ｅは炭素数１〜８のアルキル、炭素数１〜８のアルコキシ、炭素数６〜１０のアリール、ヒドロキシ、シアノ、ニトロの各基、及びハロゲンからなる群より選ばれる少なくとも１種で置換されていてもよい。Ｇは−Ｏ−、−Ｓ−、−ＳＯ−、−ＳＯ_２−、−ＮＨ−、−ＮＲ’−、−ＣＯ−、−ＣＯＯ−、−ＣＯＮＨ−、炭素数１〜３のアルキレン基、又はフェニレン基を表す。ａは０〜５の整数である。ａ＋１個のＥ及びａ個のＧはそれぞれ同一であっても異なっていてもよい。Ｒ’は前記のものと同じである。）
で表されることが好ましい。 On the other hand, the cation moiety of the component (A) is not particularly limited, but the following general formula (a2):

(In the chemical formula (a2), A represents a sulfur atom or iodine atom having a valence of m, and m is 1 or 2. n represents the number of repeating units in the structure in parentheses and is an integer of 0 to 3. R is an organic group bonded to A, an aryl group having 6 to 30 carbon atoms, a heterocyclic group having 4 to 30 carbon atoms, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, Or an alkynyl group having 2 to 30 carbon atoms, wherein R is alkyl, hydroxy, alkoxy, alkylcarbonyl, arylcarbonyl, alkoxycarbonyl, aryloxycarbonyl, arylthiocarbonyl, acyloxy, arylthio, alkylthio, aryl, heterocycle, aryl Oxy, alkylsulfinyl, arylsulfinyl, alkylsulfonyl, arylsulfonyl, alkyleneoxy, amino, And may be substituted with at least one selected from the group consisting of halogen, nitro groups, and halogen, and the number of R is m + n (m-1) +1, and R may be the same or different. In addition, two or more R's may be directly selected from each other, or —O—, —S—, —SO—, —SO ₂ —, —NH—, —NR′—, —CO—, —COO—. , -CONH-, an alkylene group having 1 to 3 carbon atoms or a phenylene group to form a ring structure containing A. R 'is an alkyl group having 1 to 5 carbon atoms or 6 to 6 carbon atoms. 10 aryl groups.
D is a structure represented by the following chemical formula (a3),

In chemical formula (a3), E represents an alkylene group having 1 to 8 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a divalent group of a heterocyclic compound having 8 to 20 carbon atoms, and E represents 1 to 1 carbon atoms. It may be substituted with at least one selected from the group consisting of 8 alkyls, C 1-8 alkoxys, C 6-10 aryls, hydroxy, cyano, nitro groups, and halogens. G is -O -, - S -, - SO -, - SO 2 -, - NH -, - NR '-, - CO -, - COO -, - CONH-, alkylene group having 1 to 3 carbon atoms, or Represents a phenylene group. a is an integer of 0-5. a + 1 E and a G may be the same or different. R ′ is the same as described above. )
It is preferable to be represented by

  Of these, a sulfonium compound is particularly desirable. By using a sulfonium compound as the cation portion, the adhesion of the thick film photoresist layer to the support is improved, and the thick film resist layer is prevented from dissolving in the developer, thereby providing a thick film resist pattern having higher resolution. Can be formed.

In the chemical formula (a2) of the cation moiety of the component (A), at least one of R is preferably an aryl group, and among these, it is more preferable that all R are aryl groups. Among them, tris (tert-butylphenyl) sulfonium where R is all tert-butylphenyl groups as shown in the chemical formula (a4) is most preferable. A thick film photoresist layer using an onium salt containing tris (tert-butylphenyl) sulfonium has a high resolution because it has particularly high adhesion to a support and low solubility in a developer. The resist pattern can be formed with high accuracy.

  By using such a component (A), the acid strength of the anion portion is increased, and the acid-catalyzed reaction of the resin when irradiated with actinic rays or radiation is promoted. Therefore, a resist pattern having high resolution can be formed on the formed thick film photoresist layer, and the focus margin when irradiated with actinic rays or radiation can be widened.

  As the component (A), only one type of onium salt having an anion moiety represented by the above chemical formula (a1) may be used, or two or more types may be used in combination. Moreover, you may use together with another conventionally well-known photo-acid generator.

As a first aspect of a conventionally known photoacid generator, 2,4-bis (trichloromethyl) -6-piperonyl-1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [ 2- (2-furyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (5-methyl-2-furyl) ethenyl] -s-triazine, 2,4-bis (Trichloromethyl) -6- [2- (5-ethyl-2-furyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (5-propyl-2-furyl) Ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3,5-dimethoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [ 2- (3,5-diethoxyphene Nyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3,5-dipropoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl)- 6- [2- (3-Methoxy-5-ethoxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3-methoxy-5-propoxyphenyl) ethenyl]- s-triazine, 2,4-bis (trichloromethyl) -6- [2- (3,4-methylenedioxyphenyl) ethenyl] -s-triazine, 2,4-bis (trichloromethyl) -6- (3 , 4-methylenedioxyphenyl) -s-triazine, 2,4-bis-trichloromethyl-6- (3-bromo-4-methoxy) phenyl-s-triazine, 2,4-bis- Lichloromethyl-6- (2-bromo-4-methoxy) phenyl-s-triazine, 2,4-bis-trichloromethyl-6- (2-bromo-4-methoxy) styrylphenyl-s-triazine, 2,4- Bis-trichloromethyl-6- (3-bromo-4-methoxy) styrylphenyl-s-triazine, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-Methoxynaphthyl) -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- (3 , 5- Dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl)- 1,3,5-triazine, 2- (3,4-methylenedioxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, tris (1,3-dibromopropyl) -1 , 3,5-triazine, tris (2,3-dibromopropyl) -1,3,5-triazine and other halogen-containing triazine compounds, and tris (2,3-dibromopropyl) isocyanurate have the following chemical formulas (a5 And a halogen-containing triazine compound represented by

In the chemical formula (a5), R ^1a , R ^2a and R ^3a each independently represent a halogenated alkyl group.

In addition, as a second embodiment of the photoacid generator, α- (p-toluenesulfonyloxyimino) -phenylacetonitrile, α- (benzenesulfonyloxyimino) -2,4-dichlorophenylacetonitrile, α- (benzenesulfonyloxy) Imino) -2,6-dichlorophenylacetonitrile, α- (2-chlorobenzenesulfonyloxyimino) -4-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, and oxime sulfonate group. Examples thereof include compounds represented by the following chemical formula (a6).

In the chemical formula (a6), R ^7a represents a monovalent, divalent, or trivalent organic group, and R ^8a represents a substituted, unsubstituted saturated hydrocarbon group, unsaturated hydrocarbon group, or aromaticity. A compound group is represented, and n represents the number of repeating units having a structure in parentheses.

In the chemical formula (a6), the aromatic compound group refers to a group of a compound that exhibits physical and chemical properties peculiar to the aromatic compound, for example, an aromatic hydrocarbon group such as a phenyl group or a naphthyl group, Heterocyclic groups such as a furyl group and a thienyl group are exemplified. These may have one or more suitable substituents on the ring, for example, a halogen atom, an alkyl group, an alkoxy group, a nitro group and the like. R ^8a is particularly preferably an alkyl group having 1 to 6 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, and a butyl group. Particularly preferred are compounds wherein R ^7a is an aromatic compound group and R ^8a is a lower alkyl group.

As the photoacid generator represented by the chemical formula (a6), when n = 1, R ^7a is any one of a phenyl group, a methylphenyl group, and a methoxyphenyl group, and R ^8a is a methyl group, Specifically, α- (methylsulfonyloxyimino) -1-phenylacetonitrile, α- (methylsulfonyloxyimino) -1- (p-methylphenyl) acetonitrile, α- (methylsulfonyloxyimino) -1- (p -Methoxyphenyl) acetonitrile, [2- (propylsulfonyloxyimino) -2,3-dihydroxythiophene-3-ylidene] (o-tolyl) acetonitrile, and the like. When n = 2, the photoacid generator represented by the chemical formula (a6) specifically includes a photoacid generator represented by the following chemical formula.

  Furthermore, the photoacid generator of another embodiment includes bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl). Bissulfonyldiazomethanes such as diazomethane; 2-nitrobenzyl p-toluenesulfonate, 2,6-dinitrobenzyl p-toluenesulfonate, nitrobenzyl tosylate, dinitrobenzyl tosylate, nitrobenzyl sulfonate, nitrobenzyl carbo Nitrobenzyl derivatives such as narate and dinitrobenzyl carbonate; pyrogallol trimesylate, pyrogallol tritosylate, benzyl tosylate, benzyl sulfonate, N-methylsulfonyloxysuccinimide Sulfonic acid esters such as N-trichloromethylsulfonyloxysuccinimide, N-phenylsulfonyloxymaleimide and N-methylsulfonyloxyphthalimide; Trifluoromethanesulfonic acid esters such as N-hydroxyphthalimide and N-hydroxynaphthalimide; Diphenyliodonium hexafluoro Phosphate, (4-methoxyphenyl) phenyliodonium trifluoromethanesulfonate, bis (p-tert-butylphenyl) iodonium trifluoromethanesulfonate, triphenylsulfonium hexafluorophosphate, (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfone Nert, (p-tert-butylphenyl) diphenylsulfonium trifluorometa Onium salts such as sulfonate; benzoin tosylate, benzoin tosylate such as α- methyl benzoin tosylate; Other Jifeniruyo - Doniumu salts, triphenylsulfonium salts, phenyldiazonium salts, benzylcarboxy na - such DOO and the like.

The photoacid generator according to another embodiment is preferably a compound represented by the above chemical formula (a6), wherein a preferable value of n is 2, and preferable R ^7a is a divalent carbon number of 1 to 8. A substituted or unsubstituted alkylene group, or a substituted or unsubstituted aromatic group, and preferred R ^8a is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, or a substituted or unsubstituted aryl. Although it is a group, it is not limited to these.

  The use ratio in the case of using such a conventionally known photoacid generator in combination may be arbitrary, but usually other photoacids with respect to 100 parts by mass of the onium salt having an anion moiety represented by the chemical formula (a1). The generator is 10 to 900 parts by weight, preferably 25 to 400 parts by weight.

  Moreover, it is preferable that (A) component contains 0.01-30 mass parts with respect to 100 mass parts of resin (henceforth (B) component) which the solubility with respect to an alkali increases by the effect | action of an acid. If the content of the component (A) is within this range, a sufficient amount of acid is generated by irradiation with actinic rays or radiation, and the increase in solubility of the component (B) becomes more complete. A pattern can be obtained. On the other hand, when the content of the component (A) is larger than this range, the sensitivity to actinic rays and radiation irradiation is too high, and the contrast between the exposed portion and the non-exposed portion may be lowered.

<(B) Resin whose solubility in alkali is increased by the action of acid>
A resin (hereinafter referred to as “component (B)”) having increased solubility in alkali due to the action of an acid (B) used in the thick film chemically amplified positive photoresist composition of the present invention has the following chemical formula (b1): A copolymer having a structural unit represented by the following chemical formula (b2), and a structural unit represented by the following chemical formula (b3).

Here, in the chemical formula (b3), R ¹ represents a hydrogen atom or a methyl group, and R ² represents an acid dissociable, dissolution inhibiting group.

Further, the acid dissociable, dissolution inhibiting group represented by R ² is not particularly limited. Specifically, a tert-butyl group, a methoxyethyl group, an ethoxyethyl group, an n-propoxyethyl group, an isopropoxyethyl group, n-butoxyethyl group, isobutoxyethyl group, tert-butoxyethyl group, cyclohexyloxyethyl group, methoxypropyl group, ethoxypropyl group, 1-methoxy-1-methyl-ethyl group, 1-ethoxy-1-methylethyl group , Tert-butoxycarbonylmethyl group, trimethylsilyl group, tri-tert-butyldimethylsilyl group and the like. Among them, a tertiary alkyl group is preferable, and a tert-butyl group is particularly preferable.

  As the component (B), the ratio of the structural units shown in the above (b1) to (b3) is such that the molar ratio l of hydroxystyrene units is 50 to 80, the molar ratio m of styrene units is 3 to 20, and the moles of acrylic units. The ratio n is 20-30. By setting it as such a copolymerization ratio, the reactivity of the acid catalyst reaction of resin can be ensured, suppressing the solubility to the developing solution of copolymerized resin, and a favorable pattern shape is obtained.

  In addition, (B) component may mix 2 or more types of resin. For example, 1: m: n = 60: 15: 25 (molecular weight 20,000) as the first polymer and 1: m: n = 70: 5: 25 (molecular weight 20,000) as the second polymer are mixed. (The ratio of the first polymer to the second polymer is preferably 3: 7 to 4: 6).

<(C) Acid diffusion controller>
The thick film chemically amplified positive photoresist composition of the present invention preferably further contains (C) an acid diffusion controller (hereinafter referred to as component (C)). By including the component (C), it is possible to improve the resist pattern shape, the stability of standing, and the like. As the component (C), a nitrogen-containing compound (C1) is preferable, and (C2) an organic carboxylic acid, an oxo acid of phosphorus, or a derivative thereof can be further contained as necessary.

[(C1) Nitrogen-containing compound]
(C1) Nitrogen-containing compounds include trimethylamine, diethylamine, triethylamine, di-n-propylamine, tri-n-propylamine, tribenzylamine, diethanolamine, triethanolamine, n-hexylamine, n-heptylamine, n -Octylamine, n-nonylamine, ethylenediamine, N, N, N ', N'-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4, 4'-diaminobenzophenone, 4,4'-diaminodiphenylamine, formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propi Amide, benzamide, pyrrolidone, N-methylpyrrolidone, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, imidazole, benz Imidazole, 4-methylimidazole, 8-oxyquinoline, acridine, purine, pyrrolidine, piperidine, 2,4,6-tri (2-pyridyl) -S-triazine, morpholine, 4-methylmorpholine, piperazine, 1,4- Examples thereof include dimethylpiperazine and 1,4-diazabicyclo [2.2.2] octane. Of these, alkanolamines such as triethanolamine are particularly preferred. These may be used alone or in combination of two or more.

  Such a (C1) nitrogen-containing compound is usually used in the range of 0 to 5 parts by mass with respect to 100 parts by mass of the component (B), but in particular in the range of 0 to 3 parts by mass. Is preferred.

[(C2) Organic carboxylic acid or phosphorus oxo acid or derivative thereof]
(C2) Among organic carboxylic acids or phosphorous oxo acids or derivatives thereof, as the organic carboxylic acid, specifically, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are preferable. In particular, salicylic acid is preferred.

  Examples of phosphorous oxo acids or derivatives thereof include phosphoric acid, phosphoric acid di-n-butyl ester, phosphoric acid diphenyl ester and other phosphoric acid or derivatives such as esters thereof, phosphonic acid, phosphonic acid dimethyl ester, phosphonic acid Phosphonic acids such as acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, phosphonic acid dibenzyl ester and derivatives thereof, phosphinic acid such as phosphinic acid, phenylphosphinic acid and esters thereof Among them, phosphonic acid is particularly preferable. These may be used alone or in combination of two or more.

  Such (C2) organic carboxylic acid or phosphorus oxo acid or derivative thereof is usually used in the range of 0 to 5 parts by mass, particularly 0 to 3 parts per 100 parts by mass of the component (B). It is preferably used in the range of parts by mass.

  In order to stabilize the formation of a salt, it is preferable to use the same amount of (C2) the organic carboxylic acid or phosphorus oxo acid or derivative thereof as the (C1) nitrogen-containing compound.

  Moreover, the chemical amplification type positive photoresist composition for thick film of the present invention may further contain an adhesion assistant in order to improve the adhesion to the substrate. As the adhesion assistant used, a functional silane coupling agent is preferable. Specific functional silane coupling agents include silane coupling agents having reactive substituents such as carboxyl groups, methacryloyl groups, isocyanate groups, and epoxy groups. Specific examples include trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and the like can be mentioned. The content of the adhesion assistant is preferably 20 parts by mass or less with respect to 100 parts by mass of the component (B).

  The thick film chemically amplified positive photoresist composition of the present invention may further contain a surfactant in order to improve defoaming properties, leveling properties, stackability on a support, and the like. Examples of surfactants include BM-1000, BM-1100 (all trade names; manufactured by BM Chemie), MegaFuck F142D, MegaFuck F172, MegaFuck F173, MegaFuck F183 (all trade names; Dainippon Ink Chemical Industry Co., Ltd.), Florard FC-135, Florard FC-170C, Florard FC-430, Florard FC-431 (all trade names; manufactured by Sumitomo 3M), Surflon S-112, Surflon S-113, Surflon S -131, Surflon S-141, Surflon S-145 (all trade names; manufactured by Asahi Glass Co., Ltd.), SH-28PA, SH-190, SH-193, SZ-6032, SF-8428 (all trade names; Toray Silicone) There are commercially available fluorosurfactants such as, but not limited to Absent.

  In addition, the chemically amplified positive photoresist composition for thick film of the present invention may further contain an acid, an acid anhydride, or a high boiling point solvent in order to finely adjust the solubility in an alkali developer. . Examples of acids and acid anhydrides include monocarboxylic acids such as acetic acid, propionic acid, n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid, benzoic acid, cinnamic acid; lactic acid, 2-hydroxybutyric acid, 3 -Hydroxy monocarboxylic acids such as hydroxybutyric acid, salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 2-hydroxycinnamic acid, 3-hydroxycinnamic acid, 4-hydroxycinnamic acid, 5-hydroxyisophthalic acid, syringic acid Oxalic acid, succinic acid, glutaric acid, adipic acid, maleic acid, itaconic acid, hexahydrophthalic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid , Butanetetracarboxylic acid, trimellitic acid, pyromellitic acid, cyclopentanetetracarboxylic acid Polyvalent carboxylic acids such as butanetetracarboxylic acid and 1,2,5,8-naphthalenetetracarboxylic acid; itaconic anhydride, succinic anhydride, citraconic anhydride, dodecenyl succinic anhydride, tricarbanilic anhydride, maleic anhydride, hexa Hydrophthalic acid, methyltetrahydrophthalic anhydride, hymic anhydride, 1,2,3,4-butanetetracarboxylic anhydride, cyclopentanetetracarboxylic dianhydride, phthalic anhydride, pyromellitic anhydride, trimellitic anhydride And acid anhydrides such as acid, anhydrous benzophenone tetracarboxylic acid, ethylene glycol bistrimellitic anhydride, and glycerin tris anhydrous trimellitate. Examples of the high boiling point solvent include N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzylethyl Ether, dihexyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, Examples thereof include propylene carbonate and phenyl cellosolve acetate. The amount of the compound used for finely adjusting the solubility in the alkali developer as described above can be adjusted according to the use / lamination method, and is particularly limited as long as the composition can be mixed uniformly. Although not a thing, it is 60 mass% or less with respect to the composition total mass obtained, Preferably it is 40 mass% or less.

  In addition, an organic solvent can be appropriately blended in the thick film chemically amplified positive photoresist composition of the present invention for viscosity adjustment. Specific examples of the organic solvent include ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, and 2-heptanone; ethylene glycol, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoacetate, propylene glycol, propylene glycol monoacetate, diester Polyhydric alcohols such as propylene glycol and dipropylene glycol monoacetate monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, or monophenyl ether and derivatives thereof; cyclic ethers such as dioxane; ethyl formate; Methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, methyl acetoacetate, ethyl acetoacetate , Ethyl pyruvate, ethyl ethoxyacetate, methyl methoxypropionate, ethyl ethoxypropionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, 2-hydroxy-3- Mention may be made of esters such as methyl methylbutanoate, 3-methoxybutyl acetate and 3-methyl-3-methoxybutyl acetate; and aromatic hydrocarbons such as toluene and xylene. These may be used alone or in combination of two or more.

  The amount of these organic solvents used is such that the thickness of the thick photoresist layer obtained by using the chemically amplified positive photoresist composition for thick film of the present invention (for example, spin coating method) is 0.1 to 100 μm. Thus, a range in which the solid content concentration is 30% by mass or more is preferable.

  The chemical amplification type positive photoresist composition for thick film of the present invention can be prepared, for example, by mixing and stirring each of the above components by a usual method. If necessary, dispersion of a dissolver, a homogenizer, a three roll mill, etc. You may disperse and mix using a machine. Further, after mixing, it may be further filtered using a mesh, a membrane filter or the like.

  The thick film chemically amplified positive photoresist composition of the present invention is obtained by laminating a thick film photoresist layer having a thickness of 0.1 to 100 μm on a support. This thick film photoresist laminate is obtained by laminating a thick film photoresist layer made of a chemically amplified positive photoresist composition for thick film of the present invention on a support.

  The support is not particularly limited, and a conventionally known one can be used. Examples thereof include a substrate for electronic parts and a substrate on which a predetermined wiring pattern is formed. Examples of the substrate include a metal substrate such as silicon, silicon nitride, titanium, tantalum, palladium, titanium tungsten, copper, chromium, iron, and aluminum, a glass substrate, and the like. In particular, it is preferable to use copper as the support. By using a support made of copper, it is possible to satisfactorily form a resist pattern made of a chemically amplified positive photoresist composition for thick films. As a material for the wiring pattern, for example, copper, solder, chromium, aluminum, nickel, gold, or the like is used.

  The thick film photoresist laminate as described above can be manufactured, for example, as follows. That is, a laminating step of laminating a desired photoresist layer by laminating a solution of a chemically amplified positive photoresist composition for thick film prepared as described above on a support and removing the solvent by heating is performed. As a lamination method on the support, methods such as a spin coating method, a slit coating method, a roll coating method, a screen printing method, and an applicator method can be employed. The pre-baking conditions for the laminate of the present invention vary depending on the type of each component in the composition, the blending ratio, the film thickness of the photoresist layer, etc., but are usually 70 to 150 ° C., preferably 80 to 140 ° C., 2 to 60 About a minute.

  Then, to form a resist pattern using the thick film photoresist laminate thus obtained, an actinic ray or radiation, for example, a wavelength, is applied to the obtained thick film photoresist layer through a mask having a predetermined pattern. Performs an exposure step of selectively irradiating (exposing) ultraviolet rays or visible rays having a wavelength of 300 to 500 nm.

Here, an actinic ray means a ray that activates an acid generator to generate an acid. As a radiation source, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, an argon gas laser, or the like can be used. Radiation means ultraviolet rays, visible rays, far ultraviolet rays, X-rays, electron beams, ion rays, and the like. The amount of radiation irradiation varies depending on the type of each component in the composition, the blending amount, the film thickness of the coating film, etc., but is, for example, 100 to 10,000 mJ / cm ² when using an ultrahigh pressure mercury lamp.

  After the exposure, the diffusion of the acid is promoted by heating using a known method to change the alkali solubility of the thick film photoresist layer in the exposed portion. Next, for example, a predetermined alkaline aqueous solution is used as a developing solution, and an unnecessary portion, for example, a portion having changed alkali solubility, is dissolved and removed to obtain a predetermined thick film resist pattern.

  Examples of the developer include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, dimethyl. Ethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5,4,0] -7-undecene, 1,5-diazabicyclo [4,3,0 An aqueous solution of an alkali such as -5-nonane can be used. Further, an aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant to the alkaline aqueous solution can also be used as a developer.

  The development time varies depending on the type of each component of the composition, the blending ratio, and the dry film thickness of the composition, but it is usually 1 to 30 minutes, and the development method is a liquid piling method, dipping method, paddle method, spray development method. Any of these may be used. After the development, washing with running water is performed for 30 to 90 seconds and dried using an air gun or an oven.

  Then, a connection terminal such as a metal post or a bump is formed by embedding a conductor such as metal in the non-resist portion (the portion removed with the alkaline developer) of the resist pattern thus obtained, for example, by plating or the like. can do. The plating method is not particularly limited, and various conventionally known methods can be employed. As the plating solution, solder plating, copper plating, gold plating, or nickel plating solution is particularly preferably used. The remaining resist pattern is finally removed using a stripping solution or the like according to a conventional method.

  Examples of the present invention will be described below, but the scope of the present invention is not limited to these examples.

<Example 1>
1 part by weight of the compound represented by the following chemical formula (z1) as the component (A), 100 parts by weight of an acrylic copolymer represented by the following chemical formula (z2), hydroxystyrene and styrene as the component (B), acid diffusion 0.54 parts by mass of salicylic acid and 0.04 parts by weight of triethylamine as control agents and 0.01 part by weight of XR-104 as surfactants are uniformly dissolved in propylene glycol monomethyl ether acetate and passed through a membrane filter having a pore size of 1 μm. Filtration was performed to obtain a chemically amplified positive resist composition for thick film.

<Comparative Example 1>
A thick film chemically amplified positive resist composition was obtained in the same manner as in Example 1 except that 1 part by mass of the compound represented by the following chemical formula (z3) was used as the component (A).

<Comparative example 2>
A thick film chemically amplified positive resist composition was obtained in the same manner as in Example 1 except that 1 part by mass of the compound represented by the following chemical formula (z4) was used as the component (A).

<Comparative Example 3>
A thick film chemically amplified positive resist composition was obtained in the same manner as in Example 1 except that 1 part by mass of the compound represented by the following chemical formula (z5) was used as the component (A).

<Evaluation>
Resist pattern formation was performed using the chemically amplified positive resist composition for thick film prepared in Example 1 and Comparative Examples 1 and 2, and the resist pattern shape on the copper substrate using SEM (scanning electron microscope) Evaluation was performed.

  Specifically, the above resist composition was laminated on a 5-inch copper substrate by a spinner, dried, and prebaked at 100 ° C. for 90 seconds using a hot plate. After pre-baking, exposure was selectively performed through a mask pattern using a KrF excimer laser stepper (manufactured by Canon; NA (numerical aperture) = 0.55, σ = 0.55). Then, a post-exposure heating (PEB) for 90 seconds at 90 ° C. was performed with a hot plate to obtain a thick photoresist layer. Thereafter, a paddle development treatment is performed for 60 seconds by a dipping method using an aqueous solution of 2.38% by weight of tetramethylammonium hydroxide (NMD-W; manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23 ° C. and washed with running water for 60 seconds. The film was post-baked for 60 seconds at 100 ° C. to obtain a line and space pattern.

  From the SEM observation results for the obtained line and space pattern, the resist pattern obtained using the chemically amplified positive resist composition for thick film of Example 1 was L / S = 0.45 μm / 0.45 μm. Whereas the resist pattern was a resist pattern obtained by using the chemically amplified positive resist composition for thick film of Comparative Examples 1 to 3, L / S = 0.50 μm / 0.50 μm. The margin was also small compared to Example 1.

Claims (8)

A chemically amplified positive photoresist composition for thick film used for forming a thick photoresist layer having a thickness of 0.1 to 100 μm on a support,
(A) a compound that generates acid upon irradiation with actinic rays or radiation, and (B) a resin whose solubility in alkali is increased by the action of the acid,
The component (A) is an onium salt having an anion moiety represented by the following chemical formula (a1):
The component (B) is a copolymer having a structural unit represented by the following chemical formula (b1), a structural unit represented by the following chemical formula (b2), and a structural unit represented by the following chemical formula (b3). A chemically amplified positive photoresist composition for thick films.

[In the chemical formula (a1), X, Y, and Z each independently represent an alkyl group having 1 to 10 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom. ]

[In the chemical formula (b3), R ¹ represents a hydrogen atom or a methyl group. R ² represents an acid dissociable, dissolution inhibiting group. l is 50 to 80, m is 3 to 20, and n is 20 to 30. ] 2. The chemically amplified positive photoresist composition for thick film according to claim 1, wherein X, Y, and Z in the chemical formula (a1) are all CF ₃ groups.   The chemically amplified positive photoresist composition for thick film according to claim 1 or 2, wherein the cation portion of the component (A) is at least one selected from sulfonium compounds. The chemically amplified positive for thick film according to any one of claims 1 to 3, wherein the acid dissociable, dissolution inhibiting group (R ² ) of the component (B) is a tertiary alkyl group. Type photoresist composition.   5. The thick film chemistry according to claim 1, wherein the component (A) is contained in an amount of 0.01 to 30 parts by mass with respect to 100 parts by mass of the component (B). Amplified positive photoresist composition.   The thick film chemically amplified positive photoresist composition according to any one of claims 1 to 5, further comprising (C) an acid diffusion control agent.   The chemically amplified positive photoresist composition for thick film according to any one of claims 1 to 6, wherein the support is a copper substrate.   A thick film photoresist in which a support and a thick film photoresist layer having a film thickness of 0.1 to 100 µm made of the chemically amplified positive photoresist composition for thick film according to any one of claims 1 to 7 are laminated. A lamination process for obtaining a laminate, an exposure process for selectively irradiating the thick film photoresist laminate with actinic rays or radiation, and a development process for developing after the exposure process to obtain a thick film resist pattern. A method for producing a thick film resist pattern.