JP4483518B2 - Etching mask composition - Google Patents

Description

  The present invention relates to an etching mask composition for producing an optical circuit used in the electronic field, optical communication field, optical information processing field and the like.

In the multimedia era, transmission systems that use light as a transmission medium have become public communication networks, LANs (local area networks), and FAs (factory automation) in response to demands for large capacity and high speed information processing in optical communication systems and computers. ), Interconnects between computers, home wiring, etc.
When an optical circuit used in these transmission systems is formed on a base material such as a silicon substrate, the surface of the base material may be etched with a predetermined pattern.

In order to perform the above-described etching, an area other than the etching mask may be etched after an etching mask (patterned etching mask layer) is formed on the substrate.
However, it has been difficult to find a composition excellent in various physical properties such as shape accuracy as a composition for forming an etching mask (etching mask composition).
Therefore, the present invention can form an etching mask having excellent transparency and heat resistance, without causing peeling at the interface or generating cracks inside, and having excellent shape accuracy at low cost. An object is to provide an etching mask composition.

The inventor of the present invention has an etching mask composition that includes a siloxane oligomer having a non-hydrolyzable organic group containing a fluorine atom and a photoacid generator as constituent components, and has various physical properties. The present invention has been completed by finding that it can be used very suitably.
That is, the present invention provides the following [1] to [5].
[1] The following components (A) and (B):
(A) at least one or more selected from the group consisting of a hydrolyzate of a hydrolyzable silane compound represented by the following general formula (1) and a condensate of the hydrolyzate;
(R ¹ ) _p (R ² ) _q Si (X) _4-pq (1)
[In General Formula (1), R ¹ is a non-hydrolyzable organic group having 1 to 12 carbon atoms, and R ² is a non-hydrolyzable organic group having 1 to 12 carbon atoms. (However, the thing containing a fluorine atom is remove | excluded.), X is a hydrolysable group, p is an integer of 1 or 2, q is an integer of 0 or 1. And (B) an etching mask composition containing a photoacid generator,
The etching mask composition characterized by the content rate of the silanol (Si-OH) group which occupies for the bonding group on all the Si in this composition being 10 to 50%.

［一般式（２）及び（３）中、Ｒ^３はフッ素原子を含有する炭素数が１〜１２である非加水分解性の有機基、Ｒ^４はフッ素原子を含んでいてもよい炭素数が１〜１２である非加水分解性の有機基であって、Ｒ^３と同じでもよい。］
［３］ 前記式（１）中のＲ^１が、ＣＦ_３（ＣＦ_２）_ｎ（ＣＨ_２）_ｍ［ｍは０〜５の整数、ｎは１〜１１の整数であり、ｍ＋ｎは１〜１１である。］である前記［２］のエッチングマスク組成物。
［４］ 前記成分（Ａ）が、さらに下記一般式（４）及び（５）からなる群より選ばれる少なくとも一種以上の構造を有する前記［２］又は［３］のエッチングマスク組成物。

［一般式（４）及び（５）中、Ｒ^５はフェニル基又はフッ素化フェニル基、Ｒ^６はフッ素原子を含んでいてもよい炭素数が１〜１２である非加水分解性の有機基であって、Ｒ^５と同じでもよい。］
［５］ 前記成分（Ａ）１００重量部に対する前記（Ｂ）光酸発生剤の添加量が０．０１〜１５重量部である前記［１］〜［４］のいずれかのエッチングマスク組成物。 [2] The etching mask composition according to [1], wherein the component (A) has at least one structure selected from the group consisting of the following general formulas (2) and (3).

[In General Formulas (2) and (3), R ³ is a non-hydrolyzable organic group containing 1 to 12 carbon atoms containing fluorine atoms, and R ⁴ is a carbon atom that may contain fluorine atoms. a non-hydrolyzable organic group is 1-12, it may be the same as R ^3. ]
[3] R ¹ in the formula (1) is CF ₃ (CF ₂ ) _n (CH ₂ ) _m [m is an integer of 0 to 5, n is an integer of 1 to 11, and m + n is 1 to 11] It is. ] The etching mask composition of [2] above.
[4] The etching mask composition according to [2] or [3], wherein the component (A) further has at least one structure selected from the group consisting of the following general formulas (4) and (5).

[In General Formulas (4) and (5), R ⁵ is a phenyl group or a fluorinated phenyl group, and R ⁶ is a non-hydrolyzable organic group having 1 to 12 carbon atoms which may contain a fluorine atom. It may be the same as R ⁵ . ]
[5] The etching mask composition according to any one of [1] to [4], wherein an addition amount of the (B) photoacid generator is 0.01 to 15 parts by weight with respect to 100 parts by weight of the component (A).

  According to the etching mask composition of the present invention, an etching mask having excellent transparency and heat resistance, without causing peeling at the interface or generating cracks inside, and having excellent shape accuracy at low cost. Can be formed.

Hereinafter, the present invention will be described in detail.
[(A) component]
The component (A) of the present invention comprises at least one selected from the group consisting of a hydrolyzate of a hydrolyzable silane compound represented by the following general formula (1) and a condensate of the hydrolyzate. The silanol group content is preferably 1 to 10 mmol / g. Here, the hydrolyzate of the hydrolyzable silane compound means, for example, a product in which an alkoxy group is changed to a silanol group by a hydrolysis reaction, but also a part of silanol groups or silanol groups and alkoxy groups. It also means a partial condensate obtained by condensing.
(R ¹ ) _p (R ² ) _q Si (X) _4-pq (1)
[In General Formula (1), R ¹ is a non-hydrolyzable organic group having 1 to 12 carbon atoms, and R ² is a non-hydrolyzable organic group having 1 to 12 carbon atoms. , X is a hydrolyzable group, p is an integer of 1 or 2, and q is an integer of 0 or 1. ]
The component (A) is generally obtained by heating the hydrolyzable silane compound represented by the general formula (1) or a mixture of this with a hydrolyzable silane compound other than the general formula (1). it can. The hydrolyzable silane compound is hydrolyzed by heating to become a hydrolyzate, or the hydrolyzate undergoes a condensation reaction to produce component (A).

(1) Organic group R ¹
R ¹ in the general formula (1) is a non-hydrolyzable organic group having 1 to 12 carbon atoms and containing a fluorine atom. Here, the term “non-hydrolyzable” means that it is a property that exists stably as it is under the condition that the hydrolyzable group X is hydrolyzed. Examples of such non-hydrolyzable organic groups include fluorinated alkyl groups and fluorinated aryl groups. Specific examples of the fluorinated alkyl group include a trifluoromethyl group, a trifluoropropyl group, a heptadecafluorodecyl group, a tridecafluorooctyl group, and a nonafluorohexyl group. Specific examples of the fluorinated aryl group include a pentafluorophenyl group.
Of these, C _n F _{2n + 1} C _m H _2m [m is an integer of 0 to 5, n is an integer of 1 to 12, and m + n is 1 to 12. A fluorinated alkyl group represented by the formula (1), having a large fluorine content such as a heptadecafluorodecyl group, a tridecafluorooctyl group, a nonafluorohexyl group, etc., and having a long chain is particularly preferable.
The subscript p in the general formula (1) is an integer of 1 or 2, but is preferably 1.

(2) Organic group R ²
R ² in the general formula (1) is a non-hydrolyzable organic group having 1 to 12 carbon atoms (excluding those containing a fluorine atom). As R ² , a non-polymerizable organic group and a polymerizable organic group, or one of the organic groups can be selected.
Here, examples of the non-polymerizable organic group include an alkyl group, an aryl group, an aralkyl group, or a deuterated or halogenated group thereof. These may be linear, branched, cyclic, or combinations thereof.
Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, a cyclohexyl group, and an octyl group. Preferred halogen atoms include fluorine, chlorine, bromine, iodine and the like.

Specific examples of the aryl group in the non-polymerizable organic group include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, a biphenyl group, a deuterated aryl group, and a halogenated aryl group.
Specific examples of the aralkyl group include a benzyl group and a phenylethyl group.
Further, a group having a structural unit containing a hetero atom may be used as the non-polymerizable organic group. Examples of the structural unit include an ether bond, an ester bond, and a sulfide bond. Moreover, when it contains a hetero atom, it is preferable that it is non-basic.

On the other hand, the polymerizable organic group is preferably an organic group having one or both of a radical polymerizable functional group and a cationic polymerizable functional group in the molecule. By introducing such a functional group, radical polymerization or cationic polymerization can be caused to cure the composition more effectively.
Further, among the radical polymerizable functional group and the cationic polymerizable functional group in the polymerizable organic group, a more preferable one is a cationic polymerizable functional group. This is because the photoacid generator can cause not only a curing reaction in a silanol group but also a curing reaction in a cationic polymerizable functional group at the same time.
Here, the subscript q in the general formula (1) is an integer of 0 or 1, but is preferably 0.

(3) Hydrolyzable group X
X in the general formula (1) is a hydrolyzable group. Here, the hydrolyzable group is usually a silanol group that is hydrolyzed by heating in a temperature range of 0 to 150 ° C. for 1 to 10 hours in the presence of a catalyst and excess water at 1 atm. Or a group capable of forming a siloxane condensate.
Here, examples of the catalyst include an acid catalyst and an alkali catalyst. Examples of the acid catalyst include monovalent or polyvalent organic acids, inorganic acids, Lewis acids, and the like. Specific examples of the organic acid include formic acid, acetic acid, oxalic acid and the like. Specific examples of the Lewis acid include metal compounds, inorganic salts such as Ti, Zr, Al, and B, alkoxides, and carboxylates. Specific examples of the alkali catalyst include alkali metal or alkaline earth metal hydroxides, amines, acidic salts, basic salts, and the like. The addition amount of the catalyst necessary for the hydrolysis is preferably 0.001 to 5%, more preferably 0.002 to 1% with respect to the total silane compound.

Specific examples of the hydrolyzable group X include a hydrogen atom, an alkoxy group having 1 to 12 carbon atoms, a halogen atom, an amino group, and an acyloxy group.
Here, preferred specific examples of the alkoxy group having 1 to 12 carbon atoms include methoxy group, ethoxy group, propoxy group, butoxy group, phenoxybenzyloxy group, methoxyethoxy group, acetoxyethoxy group, and 2- (meth) acryloxy. In addition to ethoxy group, 3- (meth) acryloxypropoxy group, 4- (meth) acryloxybutoxy group, etc., epoxy group-containing alkoxy groups such as glycidyloxy group, 2- (3,4-epoxycyclohexyl) ethoxy group, Examples thereof include oxetanyl group-containing alkoxy groups such as methyl oxetanyl methoxy group and ethyl oxetanyl methoxy group, and alkoxy groups having a 6-membered ring ether group such as oxacyclohexyloxy.

Preferred halogen atoms include fluorine, chlorine, bromine and iodine.
However, when using a hydrolyzable silane compound containing a halogen atom as the hydrolyzable group in this way, care must be taken not to reduce the storage stability of the composition. That is, although depending on the amount of hydrogen halide produced by hydrolysis, such hydrogen halide should be removed by operations such as neutralization and distillation so as not to adversely affect the storage stability of the composition. Is preferred.

(4) Specific examples of hydrolyzable silane compounds represented by general formula (1) Specific examples of hydrolyzable silane compounds represented by general formula (1) include trifluoromethyltrimethoxysilane and trifluoromethyl. Triethoxysilane, 3,3,3-trifluoropropyltrichlorosilane, methyl-3,3,3, -trifluoropropyldichlorosilane, dimethoxymethyl-3,3,3, -trifluoropropylsilane, 3,3 3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropylmethyldichlorosilane, 3,3,4,4,5,5,6,6,6-nonafluorohexyltrichlorosilane, 3,3,4 4,4,5,5,6,6,6-nonafluorohexylmethyldichlorosilane, 3,3,4,4,5,5,6,6,7,7,8,8 9,9,10,10,10-heptadecafluorodecyltrichlorosilane, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10 -Heptadecafluorodecyltrimethoxysilane, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyltriethoxysilane 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecylmethyldichlorosilane, 3-heptafluoroisopropoxypropyl Examples include triethoxysilane, pentafluorophenylpropyltrimethoxysilane, pentafluorophenylpropyltrichlorosilane and the like. Among these, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyltriethoxysilane and 3,3 , 4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyltrimethoxysilane, 3,3,4,4,5,5 1,6,6,6-nonafluorohexyltrichlorosilane and the like are preferable.

(5) Other hydrolyzable silane compounds Other hydrolyzable silane compounds include tetrachlorosilane, tetraaminosilane, tetraacetoxysilane, tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, tetraphenoxysilane, and tetrabenzyloxysilane. Silane compounds having four hydrolyzable groups such as trimethoxysilane and triethoxysilane; methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriisopropoxy It has three hydrolyzable groups such as silane, ethyltributoxysilane, butyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, deuterated methyltrimethoxysilane, etc. Or a silane compound having two hydrolyzable groups such as dimethyldichlorosilane, dimethyldiaminosilane, dimethyldiacetoxysilane, dimethyldimethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, and dibutyldimethoxysilane. .

(6) Preparation of Component (A) The method for obtaining the component (A) by heating the hydrolyzable silane compound represented by the general formula (1) is as follows unless the silanol group content described below is excessive or excessive. Although it does not specifically limit, The method which consists of the process of 1) -3) shown below as an example can be mentioned. However, in the hydrolyzate of the hydrolyzable silane compound represented by the general formula (1), a partially unhydrolyzed hydrolyzable group may remain. In that case, the hydrolyzable silane compound and the hydrolyzate It becomes a mixture with things.

1) The hydrolyzable silane compound and acid catalyst represented by the general formula (1) are accommodated in a container equipped with a stirrer.
2) Next, an organic solvent is further accommodated in the container while adjusting the viscosity of the obtained solution to obtain a mixed solution.
3) After stirring the obtained mixed solution at a temperature not higher than the boiling point of the organic solvent or hydrolyzable silane compound in an air atmosphere, at 0 to 150 ° C. for 1 to 24 hours. Stir with heating. In addition, during heating and stirring, it is also preferable to concentrate the mixed solution by distillation or replace the organic solvent as necessary. Here, in order to adjust the refractive index of the final cured product, the curability of the composition, the viscosity, and the like, a hydrolyzable silane compound other than the hydrolyzable silane compound represented by the general formula (1) is mixed. Thus, a siloxane oligomer can also be prepared. In this case, after adding and mixing the hydrolyzable silane compound of general formula (1) and the other hydrolyzable silane compound in the step 1), the reaction can be carried out by heating.

  (A) Silanol groups are generated during the component preparation process, but depending on the preparation method, the amount of silanol groups may be outside the range defined in the present invention, which may adversely affect the patterning of an etching mask by photolithography. is there. For this reason, it is preferable that the preparation process of (A) component follows the said method.

［一般式（２）及び（３）中、Ｒ^３はフッ素原子を含有する炭素数が１〜１２である非加水分解性の有機基、Ｒ^４はフッ素原子を含んでいてもよい炭素数が１〜１２である非加水分解性の有機基であって、Ｒ^３と同じでもよい。］
（Ａ）成分が上記構造を有していると、本発明のエッチングマスク組成物からなるエッチングマスクの耐クラック性等の物性をより一層向上させることができる。
さらに、前記一般式（１）のＲ^１が、ＣＦ_３（ＣＦ_２）_ｎ（ＣＨ_２）_ｍ［ｍは０〜５の整数、ｎは１〜１１の整数であり、ｍ＋ｎは１〜１１である。］であることが好ましい。Ｒ^１がこのような構造であると、本発明のエッチングマスク組成物を用いてフォトリソグラフィー法によりエッチングマスクを形成する際のパターニング性や、エッチングマスクの耐クラック性をより一層向上させることができる。 (7) Preferred Embodiment of Component (A) The component (A) preferably has at least one structure selected from the group consisting of the following general formulas (2) and (3).

[In General Formulas (2) and (3), R ³ is a non-hydrolyzable organic group containing 1 to 12 carbon atoms containing fluorine atoms, and R ⁴ is a carbon atom that may contain fluorine atoms. a non-hydrolyzable organic group is 1-12, it may be the same as R ^3. ]
When (A) component has the said structure, physical properties, such as crack resistance of the etching mask which consists of an etching mask composition of this invention, can be improved further.
Further, the ^{R 1} of the general formula (1) _{is, CF 3 (CF 2) n} (CH 2) m [m is an integer of 0 to 5, n is an integer of 1 to 11, m + n is 1 to 11 is there. ] Is preferable. When R ¹ has such a structure, the patterning property when forming an etching mask by photolithography using the etching mask composition of the present invention and the crack resistance of the etching mask can be further improved. .

［一般式（４）又は（５）中、Ｒ^５はフェニル基、あるいはフッ素化フェニル基、Ｒ^６はフッ素原子を含んでいてもよい炭素数が１〜１２である非加水分解性の有機基であってＲ^５と同じでもよい。］
これらの一般式（４）または一般式（５）の構造を有する加水分解性化合物の具体例としては、上述の一般式（１）、または一般式（１）以外の加水分解性シラン化合物の具体例のうち、フェニル基またはフッ素化フェニル基を有する化合物が挙げられる。これらのうち、フェニルトリメトキシシラン、フェニルトリエトキシシラン、ペンタフルオロフェニルトリメトキシシラン等が特に好ましい。
（Ａ）成分が上記構造を有していると、本発明のエッチングマスク組成物を用いて形成されるエッチングマスクの耐熱性やパターニング性をより一層向上させることができる。 In the case where R ¹ has the above structure, the component (A) preferably further has at least one structure selected from the group consisting of the following general formulas (4) and (5).

[In General Formula (4) or (5), R ⁵ is a phenyl group or a fluorinated phenyl group, and R ⁶ is a non-hydrolyzable organic group having 1 to 12 carbon atoms which may contain a fluorine atom. And may be the same as R ⁵ . ]
Specific examples of the hydrolyzable compound having the structure of the general formula (4) or the general formula (5) include specific examples of the hydrolyzable silane compounds other than the above general formula (1) or the general formula (1). Among the examples, compounds having a phenyl group or a fluorinated phenyl group can be mentioned. Of these, phenyltrimethoxysilane, phenyltriethoxysilane, pentafluorophenyltrimethoxysilane and the like are particularly preferable.
When (A) component has the said structure, the heat resistance and patterning property of the etching mask formed using the etching mask composition of this invention can be improved further.

[Component (B)]
The component (B) is a photoacid generator. By irradiating with radiation, the component (B) is decomposed and an acidic active substance that photocures the component (A) can be released.
Here, examples of the radiation include visible light, ultraviolet rays, infrared rays, X-rays, electron beams, α rays, and γ rays. However, it is preferable to use ultraviolet rays from the viewpoint of having a constant energy level, a high curing rate, and a relatively inexpensive and compact irradiation apparatus.

  Examples of the component (B) include an onium salt having a structure represented by the following general formula (6), a sulfonic acid derivative having a structure represented by the following general formula (7), and the like.

_{^{[R 7 a R 8 b R}} 9 c R 10 d W] + m [MZ m + n] -m (6)
[In General Formula (6), the cation is an onium ion, W is S, Se, Te, P, As, Sb, Bi, O, I, Br, Cl, or —N≡N, and R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are the same or different organic groups, a, b, c and d are each an integer of 0 to 3, and (a + b + c + d) is equal to the valence of W. M is a metal or metalloid constituting the central atom of the halide complex [MZ _{m + n} ], for example, B, P, As, Sb, Fe, Sn, Bi, Al, Ca, In, Ti, Zn, Sc, V, Cr, Mn, and Co. Z is, for example, a halogen atom or an aryl group such as F, Cl, Br, etc., m is the net charge of the halide complex ion, and n is the valence of M. ]

Q _s- [S (= O) ₂ -R ¹¹ ] _t (7)
[In the general formula (7), Q is a monovalent or divalent organic group, R ¹¹ is a monovalent organic group having 1 to 12 carbon atoms, the subscript s is 0 or 1, and the subscript t is 1 or 2. is there. ]

(1) Onium salt Specific examples of the anion [MZ _{m + n} ] in the general formula (6) include tetrafluoroborate (BF ₄ ⁻ ), hexafluorophosphate (PF ₆ ⁻ ), hexafluoroantimonate (SbF ₆ ⁻ ), Examples include hexafluoroarsenate (AsF ₆ ⁻ ), hexachloroantimonate (SbCl ₆ ⁻ ), tetraphenyl borate, tetrakis (trifluoromethylphenyl) borate, tetrakis (pentafluoromethylphenyl) borate and the like.
Further, instead of the anion _{[MZ m + n]} in the general formula (6), the general formula ^- it is also preferable to use the anion represented by _[MZ n OH]. Furthermore, perchlorate ion (ClO ₄ ⁻ ), trifluoromethane sulfonate ion (CF ₃ SO ₄ ⁻ ), fluorosulfonate ion (FSO ₄ ⁻ ), toluene sulfonate ion, trinitrobenzene sulfonate anion, trinitrotoluene sulfonate Onium salts having other anions such as anions can also be used.

［一般式（８）中、Ｒ^１２およびＲ^１３は、それぞれ独立して水素又はアルキル基、Ｒ^１４は水酸基または−ＯＲ^１５（但し、Ｒ^１５は１価の有機基である。）を示し、ａは４〜７の整数、ｂは１〜７の整数である。ナフタレン環への各置換基の結合位置は特に限定されない。］
［Ｒ^１６−Ｐｈ^１−Ｉ^＋−Ｐｈ^２−Ｒ^１７］［Ｙ⁻］ （９）
［一般式（９）中、Ｒ^１６およびＲ^１７は、それぞれ１価の有機基であり、同一でも異なっていてもよく、Ｒ^１６およびＲ^１７の少なくとも一方は、炭素数が４以上のアルキル基を有しており、Ｐｈ^１およびＰｈ^２はそれぞれ芳香族基であり、同一でも異なっていてもよく、Ｙ⁻は１価の陰イオンであり、周期律表３族、５族のフッ化物陰イオンもしくは、ＣｌＯ_４ ⁻、ＣＦ_３ＳＯ_３ ⁻から選ばれる陰イオンである。］ The onium salt is preferably an aromatic onium salt, particularly preferably a triarylsulfonium salt, a compound represented by the following general formula (8), a diaryl iodonium salt represented by the following general formula (9) or a triaryl iodonium. Salt.

[In General Formula (8), R ¹² and R ¹³ each independently represent hydrogen or an alkyl group, R ¹⁴ represents a hydroxyl group or —OR ¹⁵ (where R ¹⁵ is a monovalent organic group), a is an integer of 4 to 7, and b is an integer of 1 to 7. The bonding position of each substituent to the naphthalene ring is not particularly limited. ]
^{[R 16 -Ph 1 -I + -Ph} 2 -R 17] [Y -] (9)
[In General Formula (9), R ¹⁶ and R ¹⁷ are each a monovalent organic group and may be the same or different, and at least one of R ¹⁶ and R ¹⁷ is an alkyl group having 4 or more carbon atoms. And Ph ¹ and Ph ² are each an aromatic group, which may be the same or different, Y ⁻ is a monovalent anion, and is a group 3 or group 5 fluoride anion in the periodic table. An ion or an anion selected from ClO ₄ ⁻ and CF ₃ SO ₃ ^— . ]

Examples of the compound represented by the general formula (8) include 4-hydroxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, 4,7-dihydroxy-1 -Naphtyltetrahydrothiophenium trifluoromethanesulfonate, 4,7-di-t-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, and the like.
Further, as the diaryl iodonium salt, specifically, (4-n-decyloxyphenyl) phenyl iodonium hexafluoroantimonate, [4- (2-hydroxy-n-tetradecyloxy) phenyl] phenyl iodonium hexafluoroantimonate [4- (2-hydroxy-n-tetradecyloxy) phenyl] phenyliodonium trifluorosulfonate, [4- (2-hydroxy-n-tetradecyloxy) phenyl] phenyliodonium hexafluorophosphate, [4- (2 -Hydroxy-n-tetradecyloxy) phenyl] phenyliodonium tetrakis (pentafluorophenyl) borate, bis (4-t-butylphenyl) iodonium hexafluoroantimonate, bis (4-t-butylphenyl) Iodonium hexafluorophosphate, bis (4-t-butylphenyl) iodonium trifluorosulfonate, bis (4-t-butylphenyl) iodonium tetrafluoroborate, bis (dodecylphenyl) iodonium hexafluoroantimonate, bis (dodecylphenyl) Examples thereof include one or a combination of two or more of iodonium tetrafluoroborate, bis (dodecylphenyl) iodonium hexafluorophosphate, bis (dodecylphenyl) iodonium trifluoromethylsulfonate, and the like.

(2) Sulfonic acid derivatives The sulfonic acid derivatives represented by the general formula (7) include disulfones, disulfonyldiazomethanes, disulfonylmethanes, sulfonylbenzoylmethanes, imidosulfonates, benzoinsulfonates, 1-oxy Examples include sulfonates of 2-hydroxy-3-propyl alcohol, pyrogallol trisulfonates, benzyl sulfonates, and the like.
Among these, imide sulfonates are preferable, and trifluoromethyl sulfonate derivatives are more preferable.

(B) Although the addition amount of a photo-acid generator is not restrict | limited in particular, It is 0.01-15 weight part normally with respect to 100 weight part of (A) component. When the addition amount of the photoacid generator is less than 0.1 parts by weight, the photocurability is lowered and a sufficient curing rate tends not to be obtained. On the other hand, when the addition amount of a photo-acid generator exceeds 15 weight part, there exists a tendency for the weather resistance and heat resistance of the hardened | cured material obtained to fall.
From the viewpoint of improving the balance between the photocurability and the weather resistance of the resulting cured product, the addition amount of the photoacid generator as the component (B) is 0 with respect to 100 parts by weight of the component (A). It is preferable to set the value within the range of 1 to 10 parts by weight.

[Component (C)]
The etching mask composition of the present invention can improve the storage stability of the composition by adding (C) an organic solvent, and can impart an appropriate viscosity, thereby forming an etching mask having a uniform thickness. can do.

Examples of the organic solvent (C) include ether organic solvents, ester organic solvents, ketone organic solvents, hydrocarbon organic solvents, alcohol organic solvents, and the like. Usually, it is preferable to use an organic solvent having a boiling point under atmospheric pressure in the range of 50 to 200 ° C. and capable of uniformly dissolving each component.
Examples of such organic solvents include aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, monoalcohol solvents, polyhydric alcohol solvents, ketone solvents, ether solvents, ester solvents, nitrogen-containing solvents. A sulfur-containing solvent or the like can be used. These organic solvents are used singly or in combination of two or more.

Among these (C) organic solvents, alcohols and ketones are preferable. This is because the storage stability of the composition can be further improved.
More preferable organic solvents include at least one compound selected from the group consisting of propylene glycol monomethyl ether, ethyl lactate, methyl isobutyl ketone, methyl amyl ketone, toluene, xylene, and methanol.

  In addition, the type of (C) organic solvent is preferably selected in consideration of the coating method of the composition. For example, since a thin film having a uniform thickness can be easily obtained, it is preferable to use a spin coating method. Examples of the organic solvent used in this case include glycols such as ethylene glycol monoethyl ether and propylene glycol monomethyl ether. Ethers; Ethylene glycol alkyl ether acetates such as ethyl cellosolve acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate; Esters such as ethyl lactate and ethyl 2-hydroxypropionate; Diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl Diethylene glycols such as methyl ether; methyl isobutyl ketone, 2-heptanone, cyclohexanone Preferred to use ketones such as methyl amyl ketone, particularly ethyl cellosolve acetate, propylene glycol methyl ether acetate, ethyl lactate, it is preferable to use methyl isobutyl ketone and methyl amyl ketone.

Component (C) is added in an amount of 1 to 300 parts by weight, preferably 2 to 200 parts by weight, per 100 parts by weight of component (A). If it is in the range of 1 to 300 parts by weight, the storage stability of the composition can be improved, an appropriate viscosity can be imparted, and an etching mask having a uniform thickness can be formed.
In addition, although the addition method in particular of (C) organic solvent is not restrict | limited, For example, you may add when manufacturing (A) component and mix | blend (A) component and (B) component You may add when you do.

[Silanol group content in the composition]
The content of silanol groups in the bonding groups on all Si in the etching mask composition of the present invention needs to be 10 to 50% (preferably 20 to 40%). If it is out of this range, patterning of the target shape may not be obtained during alkali development.

[Other ingredients]
Furthermore, within the range that does not impair the object and effect of the present invention, an acid diffusion controller, a reactive diluent, a radical generator (photopolymerization initiator), a photosensitizer, a metal alkoxide, inorganic fine particles, a dehydrating agent, and a leveling agent. , Polymerization inhibitors, polymerization initiation assistants, wettability improvers, surfactants, plasticizers, UV absorbers, antioxidants, antistatic agents, silane coupling agents, polymer additives, and the like are also preferably added. .

(D) Acid Diffusion Control Agent (D) The acid diffusion control agent of component (D) controls the diffusion of the acidic active substance generated from the photoacid generator by photoirradiation in the coating and suppresses the curing reaction in the non-irradiated region. It is defined as a compound having an action. However, in order to distinguish from a photoacid generator by definition, the acid diffusion control agent of component (D) is a compound that does not have an acid generation function.
By adding such an acid diffusion controller, the composition of the present invention can be effectively cured and the pattern accuracy can be improved.

As a kind of (D) component acid-diffusion controlling agent, the nitrogen-containing organic compound whose basicity does not change with the exposure in a formation process or heat processing is preferable.
Examples of such nitrogen-containing organic compounds include compounds represented by the following general formula (10).
NR ¹⁸ R ¹⁹ R ²⁰ (10)
[In General Formula (10), R ¹⁸ , R ¹⁹ and R ²⁰ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group. To express. ]

Other nitrogen-containing organic compounds include diamino compounds having two nitrogen atoms in the same molecule, diamino polymers having three or more nitrogen atoms, amide group-containing compounds, urea compounds, nitrogen-containing heterocycles. A compound etc. can be mentioned.
Specific examples of the nitrogen-containing organic compound include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; di-n-butylamine, di-n -Dialkylamines such as pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine; triethylamine, tri-n-propylamine , Tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, etc. Amines; aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, - methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, aromatic amines such as 1-naphthylamine; can be mentioned ethanolamine, diethanolamine, alkanolamines such as triethanolamine and the like.
In addition, an acid diffusion control agent can also be used individually by 1 type, or can also be used in mixture of 2 or more types.

(D) It is preferable that the addition amount of an acid diffusion controller is a value within the range of 0.001 to 15 parts by weight with respect to 100 parts by weight of component (A).
The reason for this is that when the amount of the acid diffusion control agent added is less than 0.001 part by weight, depending on the process conditions, the pattern shape and dimensional reproducibility of the etching mask may be lowered. It is because the photocurability of (A) component may fall when the addition amount of a control agent exceeds 15 weight part.
Therefore, the addition amount of the acid diffusion control agent is more preferably set to a value within the range of 0.001 to 10 parts by weight with respect to 100 parts by weight of the component (A), and the range of 0.005 to 5 parts by weight. More preferably, the value is within the range.

  Moreover, the etching mask composition of this invention can form easily the etching mask which has a different refractive index by selecting the kind of (A) component. Therefore, when the etching mask is used as a permanent film even after the etching process is completed, an optically necessary refractive index can be designed.

  The viscosity of the etching mask composition of the present invention is preferably 5 to 5,000 mPa · s, more preferably 10 to 1,000 mPa · s at 25 ° C. If the viscosity exceeds 5,000 mPa · s, it may be difficult to form a uniform coating film (etching mask layer). The viscosity of the composition of this invention can be suitably adjusted with the compounding quantity of a reactive diluent and an organic solvent.

Next, a method for forming an etching mask using the etching mask composition of the present invention will be described. FIG. 1 is a flow chart showing an example of a method for forming an etching mask using the etching mask composition of the present invention.
First, as shown in FIG. 1A, a substrate 1 having a flat surface is prepared. The type of the substrate 1 is not particularly limited. For example, a silicon substrate can be used.
Next, as shown in FIG. 1 (b), the etching mask composition of the present invention is applied to the surface of the silicon substrate 1 and dried or pre-baked (preferably heated at 50 to 200 ° C.) to form a thin film. (Etching mask layer 2) is formed.
Here, as a coating method of the etching mask composition, a spin coating method, a dipping method, a spray method, a bar coating method, a roll coating method, a curtain coating method, a gravure printing method, a silk screen method, an ink jet method or the like is used. Can be used. Among these, it is more preferable to employ the spin coat method because an etching mask layer having a particularly uniform thickness can be obtained.
Moreover, in order to make the rheological characteristics of the composition for etching mask appropriately correspond to the coating method, additives other than the surface tension reducing agent can be blended as necessary.

Thereafter, as shown in FIG. 1C, the upper surface of the etching mask layer 2 is irradiated with light (radiation) 4 through a photomask 3 having a predetermined line pattern, for example, according to a predetermined pattern. Do. Thereby, since only the portion irradiated with light is cured, the other uncured portion is developed and removed by the developer, and as shown in FIG. 1 (d), on the silicon substrate 1, An etching mask 5 made of a patterned cured film can be formed.
Here, the light used for forming the etching mask is not particularly limited, and visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays, γ-rays, and the like can be used. Light in the ultraviolet to visible region of 450 nm, more preferably light including ultraviolet light having a wavelength of 365 nm is used. Irradiation at wavelengths 200~450nm, the illuminance is 1~1000mW / cm ^2, irradiation amount 0.01~5000mJ / cm ^2, and preferably is carried out such that the 0.1~1000mJ / cm ^2, is exposed The
Examples of the light irradiation device include a lamp light source that simultaneously irradiates a wide area such as a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, and an excimer lamp, and a laser light source such as a pulse or continuous light source, or both of them. Accordingly, a mirror, a lens, or an optical fiber that generates convergent light can be used.
In the case of forming an etching mask using convergent light, exposure can be performed so as to have an etching mask shape by moving either the convergent light or the irradiated object. Among these light sources, a light source with high ultraviolet intensity of 365 nm is preferable. For example, a high pressure mercury lamp is preferable as a lamp light source, and an argon laser is preferable as a laser light source.

The method of irradiating light according to a predetermined pattern is not limited to a method using a photomask composed of a light transmitting portion and a non-transmitting portion, and examples thereof include the following methods a to c.
a. A method using electro-optical means for forming a mask image composed of a light transmission region and a non-transmission region according to a predetermined pattern, using the same principle as that of a liquid crystal display device.
b. A method of irradiating light through an optical fiber corresponding to a predetermined pattern in the light guide member using a light guide member formed by bundling a large number of optical fibers.
c. A method of irradiating a photocurable composition while scanning a laser beam or convergent light obtained by a condensing optical system such as a lens or a mirror.

After exposure, it is preferable to perform heat treatment (hereinafter referred to as “PEB”) in order to promote curing of the exposed portion. The heating conditions vary depending on the composition of the composition of the present invention, the type of additive, and the like, but are usually 30 to 200 ° C, preferably 50 to 150 ° C.
Developers include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, ethanolamine, N-methylethanolamine, N, N-dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, choline, pyrrole, piperidine, 1,8-diazabicyclo [5.4 .0] -7-undecene, 1,5-diazabicyclo [4.3.0] -5-nonane and water, methanol, ethanol, propyl alcohol, butanol, octano Le, propylene glycol monomethyl ether, propylene glycol monoethyl ether, N- methylpyrrolidone, formamide, N, N- dimethylformamide, N, N- dimethylacetamide can be used a solution diluted with a solvent such as.
The concentration of the basic substance in the developer is usually 0.05 to 25% by weight, preferably 0.1 to 3.0% by weight.

The development time is usually 30 to 600 seconds. As a developing method, a known method such as a liquid piling method, a dipping method, or a shower developing method can be employed.
When an organic solvent is used as the developer, it is directly air-dried. When an alkaline aqueous solution is used, it is washed with running water for 30 to 90 seconds and then air-dried with compressed air or compressed nitrogen. By removing moisture on the surface, a patterned film can be formed.
In order to further cure the patterned film, a cured etching mask 5 is formed by post-baking, for example, at a temperature of 30 to 400 ° C. for 5 minutes to 72 hours with a heating device such as a hot plate or an oven. become.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
[Preparation of component (A)]
[Synthesis Example 1]
In a flask equipped with a stirrer and a reflux tube, phenyltrimethoxysilane (30.79 g), 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10, Add 10,10-heptadecafluorodecyltriethoxysilane (22.64 g), tetraethoxysilane (4.62 g), 1-methoxy-2-propanol (29.93 g), and oxalic acid (0.04 g), After stirring, the temperature of the solution was heated to 60 ° C. Then, distilled water (11.98 g) was added dropwise, and after completion of the addition, the solution was stirred at 120 ° C. for 6 hours. And the 1-methoxy-2-propanol solution of (A) component which finally adjusted solid content to 65 weight% was obtained. This is designated as “siloxane oligomer solution 1”.

[Synthesis Example 2]
In a flask equipped with a stirrer and a reflux tube, phenyltrimethoxysilane (30.56 g), 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10, 10,10-heptadecafluorodecyltriethoxysilane (18.15 g), tetraethoxysilane (9.88 g), methyl-n-amyl ketone (27.72 g), and oxalic acid (0.04 g) were added and stirred. Later, the temperature of the solution was heated to 60 ° C. Then, distilled water (13.66 g) was added dropwise, and after completion of the addition, the solution was stirred at 120 ° C. for 6 hours. And the methyl- n-amyl ketone solution of (A) component which finally adjusted solid content to 70 weight% was obtained. This is designated as “siloxane oligomer solution 2”.

[Synthesis Example 3]
In a flask equipped with a stirrer and a reflux tube, methyltrimethoxysilane (2.97 g), phenyltrimethoxysilane (29.01 g), 3,3,4,4,5,5,6,6,7,7, Add 8,8,9,9,10,10,10-heptadecafluorodecyltriethoxysilane (25.64 g), 1-methoxy-2-propanol (31.00 g), and oxalic acid (0.04 g) After stirring, the temperature of the solution was heated to 60 ° C. Then, distilled water (11.35 g) was added dropwise, and after completion of the addition, the solution was stirred at 120 ° C. for 6 hours. And the 1-methoxy-2-propanol solution of (A) component which finally adjusted solid content to 70 weight% was obtained. This is designated as “siloxane oligomer solution 3”.

[Preparation of Etching Mask Composition 1]
As a photoacid generator, 0.32 g of 4,7-di-t-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, tri-n- is used as a photoacid generator for 92.56 g of siloxane oligomer solution 1 (solid content and organic solvent). 0.03 g of octylamine and 7.09 g of 1-methoxy-2-propanol were added and mixed uniformly to obtain “Composition 1” in which the solid content concentration was adjusted to 65% by weight.

[Preparation of Etching Mask Composition 2]
As a photoacid generator, 0.32 g of 4,7-di-t-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, tri-n- is used as a photoacid generator for 92.56 g of siloxane oligomer solution 2 (solid content and organic solvent). 0.03 g of octylamine and 7.09 g of 1-methoxy-2-propanol were added and mixed uniformly to obtain “Composition 2” in which the solid content concentration was adjusted to 65% by weight.

[Preparation of Etching Mask Composition 3]
As a photoacid generator, 0.32 g of 4,7-di-t-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate, tri-n- is used as the photoacid generator for 92.56 g of the siloxane oligomer solution 3 (solid content and organic solvent). 0.03 g of octylamine and 7.09 g of 1-methoxy-2-propanol were added and mixed uniformly to obtain “Composition 3” in which the solid content concentration was adjusted to 65% by weight.

[Example 1]
Composition 1 was applied onto the surface of a silicon substrate with a spin coater, dried at 80 ° C. for 2 minutes, and then a wavelength of 365 nm and an illuminance of 20 mW / cm using a photomask engraved with a linear pattern of line / space = 50/150 μm. The ultraviolet rays of No. ² were irradiated for 10 seconds with an exposure machine (Photo aligner manufactured by SUSS Microtec). Thereafter, this substrate was heated at 100 ° C. for 1 minute, and then immersed in a developer composed of a 5% tetramethylammonium hydroxide (TMAH) aqueous solution to dissolve unexposed portions, and further washed with water. Then, after irradiating with ultraviolet rays for 1 minute, an etching mask having a thickness of 10 μm was formed by heating at 300 ° C. for 1 hour.
Next, when this substrate was wet-etched by TMAH, it was found that there was no change in the thickness of the etching mask before and after the etching, and the etching mask was not damaged even under the etching conditions. In addition, the silicon substrate was etched.

[Example 2]
An etching mask was prepared and evaluated in the same manner as in Example 1 except that the composition 2 was used in place of the composition 1. As a result, the etching mask was not damaged and only the silicon substrate was etched.
[Example 3]
An etching mask was prepared and evaluated in the same manner as in Example 1 except that the composition 3 was used in place of the composition 1. As a result, the etching mask was not damaged and only the silicon substrate was etched.

[Silanol content measurement]
Each of Compositions 1 to 3 was diluted with deuterated chloroform as an NMR measurement solvent, and the silanol content was measured by Si-NMR. Specifically, a plurality of silane components having different substituents and bonding groups appearing at −120 ppm to −60 ppm were peak-separated by curve fitting, and the mol% of each component was calculated from the peak area ratio. By multiplying the number of silanol groups in each of the obtained components, the ratio (%) to the bonding groups on the total Si was calculated.
An example calculation is shown below.
Mole% Number of silanol groups Peak 1: R—Si (OH) ₃ a 3
Peak 2: R—Si (OH) ₂ (OSi) b 2
Peak 3: R—Si (OH) (OSi) ₂ c 1
Peak 4: R—Si (OSi) ₃ d 0

Silanol content in all Si bonding groups (%)
= (3a + 2b + c) × 100 / [4 × (a + b + c + d)]
As a result, the silanol contents of Composition 1, Composition 2 and Composition 3 were 29%, 28% and 30%, respectively.

It is a flowchart which shows an example of the formation method of the etching mask using the etching mask composition of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Silicon substrate 2 Etching mask layer 3 Photomask 4 Light 5 Etching mask

Claims (5)

The following components (A) and (B):
(A) at least one or more selected from the group consisting of a hydrolyzate of a hydrolyzable silane compound represented by the following general formula (1) and a condensate of the hydrolyzate;
(R ¹ ) _p (R ² ) _q Si (X) _4-pq (1)
[In General Formula (1), R ¹ is a non-hydrolyzable organic group having 1 to 12 carbon atoms, and R ² is a non-hydrolyzable organic group having 1 to 12 carbon atoms. (However, the thing containing a fluorine atom is remove | excluded.), X is a hydrolysable group, p is an integer of 1 or 2, q is an integer of 0 or 1. ]
And (B) an etching mask composition containing a photoacid generator,
The etching mask composition characterized by the content rate of the silanol (Si-OH) group which occupies for the bonding group on all the Si in this composition being 10 to 50%. The etching mask composition according to claim 1, wherein the component (A) has at least one structure selected from the group consisting of the following general formulas (2) and (3).

[In General Formulas (2) and (3), R ³ is a non-hydrolyzable organic group containing 1 to 12 carbon atoms containing fluorine atoms, and R ⁴ is a carbon atom that may contain fluorine atoms. a non-hydrolyzable organic group is 1-12, it may be the same as R ^3. ] R ¹ in the formula (1) is CF ₃ (CF ₂ ) _n (CH ₂ ) _m [m is an integer of 0 to 5, n is an integer of 1 to 11, and m + n is 1 to 11. The etching mask composition according to claim 2. The etching mask composition according to claim 2 or 3, wherein the component (A) further has at least one structure selected from the group consisting of the following general formulas (4) and (5).

[In General Formulas (4) and (5), R ⁵ is a phenyl group or a fluorinated phenyl group, and R ⁶ is a non-hydrolyzable organic group having 1 to 12 carbon atoms which may contain a fluorine atom. It may be the same as R ⁵ . ] The etching mask composition according to any one of claims 1 to 4, wherein an addition amount of the (B) photoacid generator is 0.01 to 15 parts by weight with respect to 100 parts by weight of the component (A).

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