阅读说明：本技术 感放射线性组合物、硬化膜及其制造方法、半导体元件、显示元件以及聚合物 (Radiation-sensitive composition, cured film and method for producing same, semiconductor element, display element, and polymer ) 是由 中西拓也 浅冈高英 成子朗人 于 2021-04-22 设计创作，主要内容包括：本发明的课题在于提供一种可获得显影密接性优异的膜的感放射线性组合物、硬化膜及其制造方法、半导体元件、显示元件以及聚合物。一种感放射线性组合物,含有：包含具有式(1)所表示的基的结构单元(I)的聚合物、光酸产生剂、及原酸酯化合物。式(1)中,R～(1)为氢原子、卤素原子、羟基或碳数1～6的烷氧基。R～(2)及R～(3)分别独立地为氢原子、卤素原子、羟基、碳数1～6的烷氧基、碳数1～10的烷基或苯基。“*”表示键结键。(The invention provides a radiation-sensitive composition capable of obtaining a film with excellent development adhesion, a hardened film and a manufacturing method thereof, a semiconductor element, a display element and a polymer. A radiation-sensitive composition comprising: a polymer comprising a structural unit (I) having a group represented by the formula (1), a photoacid generator, and an orthoester compound. In the formula (1), R 1 Is hydrogen atom, halogen atom, hydroxyl or C1-6 alkoxy. R 2 And R 3 Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 10 carbon atoms or a phenyl group. "+" indicates a bondAnd (6) binding.)

1. A radiation-sensitive composition comprising:

at least one selected from the group consisting of a polymer containing a structural unit (I) having a group represented by the following formula (1) and a siloxane polymer;

a photoacid generator; and

an orthoester compound of an acid or a salt thereof,

in the formula (1), R¹Hydrogen atom, halogen atom, hydroxyl or alkoxy with 1-6 carbon atoms; r²And R³Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 10 carbon atoms, or a phenyl group; "" indicates a bond.

2. The radiation-sensitive composition of claim 1, comprising:

a silicon-containing polymer which is at least one selected from the group consisting of a polymer containing a structural unit (I) having a group represented by the following formula (1) and a siloxane polymer;

a photoacid generator; and

an orthoester compound having a boiling point of 105 ℃ or higher,

in the formula (1), R¹Hydrogen atom, halogen atom, hydroxyl or alkoxy with 1-6 carbon atoms; r²And R³Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atomsAn alkyl group having 1 to 10 carbon atoms or a phenyl group; "" indicates a bond.

3. The radiation-sensitive composition according to claim 1, wherein the orthoester compound has a boiling point of 105 ℃ or higher.

4. The radiation-sensitive composition according to claim 1, wherein the orthoester compound is a compound represented by the following formula (2),

R³³-C-(OR³²)₃…(2)

in the formula (2), R³²Is alkyl or phenyl with 1-4 carbon atoms; r³³A monovalent chain hydrocarbon group having 1 to 4 carbon atoms or a monovalent aromatic ring group having 6 to 12 carbon atoms; three of R in the formula³²Are the same group as each other or different groups.

5. The radiation-sensitive composition of any one of claims 1 to 4, wherein the orthoester compound has an aromatic ring group.

6. The radiation-sensitive composition according to any one of claims 1 to 4, wherein the group represented by formula (1) is bonded to an aromatic ring group or a chain hydrocarbon group.

7. The radiation-sensitive composition according to any one of claims 1 to 4, wherein the structural unit (I) has at least one selected from the group consisting of a group represented by the following formula (3-1), a group represented by the following formula (3-2), and a group represented by the following formula (3-3),

in the formulae (3-1), (3-2) and (3-3), A¹And A²Independently represents a halogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms; n1 is an integer of 0-4; n2 is an integer of 0-6; wherein, inWhen n1 is 2 or more, A' s¹Are the same group or different groups from each other; when n2 is 2 or more, a plurality of A²Are the same group or different groups from each other; r⁶Is alkanediyl; r¹、R²And R³The same as the formula (1); "" indicates a bond.

8. The radiation-sensitive composition of any one of claims 1 to 4, wherein the photoacid generator comprises at least one selected from the group consisting of an oxime sulfonate compound and a sulfonimide compound.

9. The radiation-sensitive composition according to any one of claims 1 to 4, further comprising an acid diffusion controlling agent.

10. A method for manufacturing a hardened film, comprising:

a step of forming a coating film using the radiation-sensitive composition according to any one of claims 1 to 9;

irradiating at least a part of the coating film with radiation;

a step of developing the coating film irradiated with the radiation; and

and heating the developed coating film.

11. A hardened film formed using the radiation-sensitive composition according to any one of claims 1 to 9.

12. A semiconductor element comprising the cured film according to claim 11.

13. A display element comprising the semiconductor element according to claim 12.

14. A polymer comprising a structural unit (I) having a group represented by the following formula (1),

in the formula (1), R¹Hydrogen atom, halogen atom, hydroxyl or alkoxy with 1-6 carbon atoms; r²And R³Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 10 carbon atoms, or a phenyl group; "X" indicates a bond of a bond,

the content ratio of the structural unit (I) in the polymer is 5% by mass or more and 50% by mass or less with respect to the total structural units constituting the polymer.

15. The polymer of claim 14, further comprising: at least one member selected from the group consisting of a structural unit (II) having at least one member selected from the group consisting of an oxetanyl group and an oxetanyl group, and a structural unit (III) having an acid group.

Technical Field

The present invention relates to a radiation-sensitive composition, a cured film and a method for producing the same, a semiconductor device, a display device, and a polymer.

Background

A cured film such as an interlayer insulating film, a spacer, and a protective film of a display element is generally formed using a radiation-sensitive composition. As a material for forming these hardened films, a radiation-sensitive composition has been proposed, which contains: a polymer having a silicon-containing functional group such as an alkoxysilyl group, a silicon-containing polymer such as a siloxane polymer, and a photoacid generator (see, for example, patent documents 1 and 2).

When a coating film is formed using the radiation-sensitive composition of patent document 1, an acid is generated from the photoacid generator by exposure at the time of pattern formation, and the generated acid decomposes an alkoxy group to solubilize the exposed portion with respect to a developer. The unexposed portion is insoluble in alkali, and after development, is heated to be subjected to dehydration condensation and hardening, thereby forming a hardened film. In addition, in the radiation-sensitive composition of patent document 2, an acid generated from the photoacid generator by exposure serves as a catalyst to promote self-crosslinking of the siloxane polymer, thereby forming a cured film.

[ Prior art documents ]

[ patent document ]

[ patent document 1] Japanese patent laid-open publication No. 2017-107024

[ patent document 2] International publication No. 2011/065215

Disclosure of Invention

[ problems to be solved by the invention ]

When a cured film is formed using the radiation-sensitive composition of patent document 1 or patent document 2, there is a concern that the adhesion of unexposed portions to a substrate may be reduced.

The present invention has been made in view of the above problems, and a main object of the present invention is to provide a radiation-sensitive composition capable of forming a film having excellent development adhesion.

[ means for solving problems ]

The present inventors have found that the above problems can be solved by formulating a specific compound in a radiation-sensitive composition. That is, the present invention provides the following radiation-sensitive composition, cured film and method for producing the same, semiconductor device, and display device.

[1] A radiation-sensitive composition comprising: a polymer and/or siloxane polymer containing a structural unit (I) having a group represented by the following formula (1), a photoacid generator, and an orthoester (ortho ester) compound.

[ solution 1]

(in the formula (1), R¹Is hydrogen atom, halogen atom, hydroxyl or C1-6 alkoxy. R²And R³Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 10 carbon atoms or a phenyl group. "+" indicates a bond)

[2] A radiation-sensitive composition comprising: a silicon-containing polymer which is at least one selected from the group consisting of a polymer comprising a structural unit (I) having a group represented by the formula (1) and a siloxane polymer; a photoacid generator; and an orthoester compound having a boiling point of 105 ℃ or higher.

[3] A method for manufacturing a hardened film, comprising: a step of forming a coating film using the radiation-sensitive composition according to [1] or [2 ]; irradiating at least a part of the coating film with radiation; developing the coating film irradiated with the radiation; and heating the developed coating film.

[4] A cured film formed using the radiation-sensitive composition according to [1] or [2 ].

[5] A semiconductor element comprising the hardened film of [4 ].

[6] A display element comprising the semiconductor element of [5 ].

[7] A polymer comprising a structural unit (I) having a group represented by the formula (1), wherein the content of the structural unit (I) in the polymer is 5 to 50 mass% based on the total structural units constituting the polymer.

[ Effect of the invention ]

According to the radiation-sensitive composition of the present invention, a coating film having excellent development adhesion can be formed by including the silicon-containing polymer, the photoacid generator, and the orthoester compound.

Detailed Description

The following describes details of the embodiments. In the present specification, the numerical range described by "to" is used to mean that the numerical values described before and after "to" are included as the lower limit value and the upper limit value. The "structural unit" means a unit mainly constituting the main chain structure, and means that two or more units are contained in at least the main chain structure.

[ radiation-sensitive composition ]

The radiation-sensitive composition of the present disclosure is used, for example, for forming a hardened film of a display element. The radiation-sensitive composition is a positive resin composition containing [ A ] a polymer component, [ B ] an orthoester compound and [ C ] a photoacid generator. Hereinafter, each component contained in the radiation-sensitive composition of the present disclosure and other components blended as necessary will be described. In addition, as for each component, one kind may be used alone or two or more kinds may be used in combination unless otherwise specified.

Here, the term "hydrocarbon group" as used herein includes chain hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups. The "chain hydrocarbon group" refers to a straight-chain hydrocarbon group and a branched hydrocarbon group which do not contain a cyclic structure in the main chain and are composed of only a chain structure. The polymer may be saturated or unsaturated. The "alicyclic hydrocarbon group" refers to a hydrocarbon group that contains only an alicyclic hydrocarbon structure as a ring structure and does not contain an aromatic ring structure. The alicyclic hydrocarbon compound is not necessarily composed of only the structure of the alicyclic hydrocarbon, and includes a group having a chain structure in a part thereof. The "aromatic hydrocarbon group" refers to a hydrocarbon group containing an aromatic ring structure as a ring structure. In addition, the structure may not necessarily be composed of only an aromatic ring structure, and may include a chain structure or an alicyclic hydrocarbon structure in a part thereof. The ring structure of the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a substituent including a hydrocarbon structure. "Cyclic hydrocarbon group" is intended to include alicyclic hydrocarbon groups and aromatic hydrocarbon groups.

[ A ] Polymer component

[A] The polymer component contains a silicon-containing polymer, which is at least one selected from the group consisting of a polymer (hereinafter also referred to as "polymer (S)") containing a structural unit (I) having a group represented by the following formula (1) and a siloxane polymer.

[ solution 2]

(in the formula (1), R¹Is hydrogen atom, halogen atom, hydroxyl or C1-6 alkoxy. R²And R³Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 10 carbon atoms or a phenyl group. "+" indicates a bond)

(Polymer (S))

Structural Unit (I)

In the formula (1), as R¹～R³Examples of the alkoxy group having 1 to 6 carbon atoms include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, and tert-butoxy groups. In these, R¹～R³The alkoxy group of (a) is preferably a methoxy group or an ethoxy group.

R²、R³The alkyl group having 1 to 10 carbon atoms may be either straight or branched. As R²、R³Examples of the alkyl group in (b) include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. In these, R²、R³The alkyl group of (a) is preferably a methyl, ethyl or propyl group.

In view of obtaining a cured film having excellent heat resistance and chemical resistance by forming a crosslinked structure and in view of improving storage stability of the radiation-sensitive composition, R is¹～R³At least one of these is preferably an alkoxy group having 1 to 6 carbon atoms, more preferably two or more, and particularly preferably all.

In the above, R¹Preferably an alkoxy group having 1 to 6 carbon atoms, and more preferably an alkoxy group having 1 to 3 carbon atoms. In the case where the group represented by the formula (1) is bonded to an aromatic ring group, R¹Methoxy is preferred. When the group represented by the formula (1) is bonded to a chain hydrocarbon group, R¹Ethoxy is preferred. R²And R³Preferably a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, an alkyl group having 1 to 10 carbon atoms or a phenyl group, more preferably a hydroxyl group, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms.

In the structural unit (I), the group represented by the formula (1) is preferably bonded to an aromatic ring group or a chain hydrocarbon group. Here, the "aromatic ring group" in the present specification means a group obtained by removing n (n is an integer) hydrogen atoms from the ring portion of an aromatic ring. Examples of the aromatic ring include a benzene ring, a naphthalene ring, and an anthracene ring. The ring may have a substituent such as an alkyl group. Examples of the chain hydrocarbon group to which the group represented by the formula (1) is bonded include an alkanediyl group and an alkanediyl group.

In the above, the group represented by the formula (1) is preferably bonded to a benzene ring, a naphthalene ring or an alkyl chain. That is, the structural unit (I) preferably has at least one selected from the group consisting of a group represented by the following formula (3-1), a group represented by the following formula (3-2), and a group represented by the following formula (3-3).

[ solution 3]

(in the formulae (3-1), (3-2) and (3-3), A¹And A²Independently represents a halogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms. n1 is an integer of 0 to 4. n2 is an integer of 0 to 6. Wherein, when n1 is 2 or more, a plurality of A¹Are the same group as each other or different groups. When n2 is 2 or more, a plurality of A²Are the same group as each other or different groups. R⁶Is alkanediyl. R¹、R²And R³The same as the formula (1). "" indicates a bond).

In the formulae (3-1) and (3-2), with respect to A¹And A²Examples of the alkoxy group having 1 to 6 carbon atoms and the alkyl group having 1 to 6 carbon atoms in (b) are R in the formula (1)¹～R³And (4) description. radicals-SiR bound to aromatic rings¹R²R³"is located relative to the other components except A¹And A²Other groups than these may be in any position. For example, "-SiR in the case of said formula (3-1)¹R²R³The "position" may be any of ortho-, meta-, and para-positions, and is preferably the para-position. n1 is preferably 0 or 1, more preferably 0. n2 is preferably 0 to 2, more preferably 0.

In the formula (3-3), R⁶Preferably straight chain. From the viewpoint of improving the heat resistance of the resulting cured film, R⁶Preferably 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms.

In the formulae (3-1) to (3-3), the structural unit (I) preferably has at least one selected from the group consisting of the group represented by the formula (3-1) and the group represented by the formula (3-2), in terms of improving the heat resistance, chemical resistance and hardness of the cured film. In addition, in the radical-SiR¹R²R³"directly bonding to an aromatic ring stabilizes silanol groups generated in association with the presence of water. This is preferable in that the solubility of the exposed portion in an alkali developing solution can be improved, and a favorable pattern can be formed. Among these, the structural unit (I) is particularly preferably a structural unit having a group represented by the above formula (3-1).

The structural unit (1) is preferably a structural unit derived from a monomer having a polymerizable carbon-carbon unsaturated bond (hereinafter also referred to as an "unsaturated monomer"), and specifically, is preferably at least one selected from the group consisting of a structural unit represented by the following formula (4-1) and a structural unit represented by the following formula (4-2).

[ solution 4]

(formula (II)(4-1) and in the formula (4-2), R^AIs hydrogen atom, methyl, hydroxymethyl, cyano or trifluoromethyl. R⁷And R⁸Each independently is a divalent aromatic ring group or chain hydrocarbon group. R¹、R²And R³The same as the above formula (1)

In the formulae (4-1) and (4-2), R⁷、R⁸The divalent aromatic ring group of (b) is preferably a substituted or unsubstituted phenylene group or a substituted or unsubstituted naphthylene group. The divalent chain hydrocarbon group is preferably an alkanediyl group having 1 to 6 carbon atoms, and more preferably an alkanediyl group having 1 to 4 carbon atoms.

R is a group capable of improving the solubility of an exposed portion in an alkali developing solution, in terms of obtaining a cured film having higher heat resistance, chemical resistance and hardness⁷、R⁸Among them, a divalent aromatic cyclic group is preferable, and a substituted or unsubstituted phenylene group is particularly preferable.

Specific examples of the structural unit represented by the above formula (4-1) include structural units represented by the following formulae (4-1-1) and (4-1-2), respectively. Specific examples of the structural unit represented by the above formula (4-2) include structural units represented by the following formulae (4-2-1) and (4-2-2), respectively.

[ solution 5]

(formula (4-1-1), formula (4-1-2), formula (4-2-1) and formula (4-2-2) wherein R¹¹And R¹²Each independently is an alkyl group having 1 to 4 carbon atoms, R¹³Is alkyl group having 1 to 4 carbon atoms, alkoxy group having 1 to 4 carbon atoms or hydroxyl group. n3 is an integer of 1 to 4. A. the¹、A²N1 and n2 are as defined in the above formulae (3-1) and (3-2). R^AThe same as the above-mentioned formula (4-1) and formula (4-2)

Specific examples of the monomer constituting the structural unit (I) include compounds having a group represented by the formula (3-1), such as styryltrimethoxysilane, styryltriethoxysilane, styrylmethyldimethoxysilane, styrylethyldiethoxysilane, styryldimethoxyhydroxysilane, styryldiethoxyhydroxysilane, (meth) acryloyloxyphenyltrimethoxysilane, (meth) acryloyloxyphenyltriethoxysilane, (meth) acryloyloxyphenylmethoxydimethoxysilane, (meth) acryloyloxyphenylethyldiethoxysilane;

examples of the compound having a group represented by the formula (3-2) include trimethoxy (4-vinylnaphthyl) silane, triethoxy (4-vinylnaphthyl) silane, methyldimethoxy (4-vinylnaphthyl) silane, ethyldiethoxy (4-vinylnaphthyl) silane, (meth) acryloyloxynaphthyltrimethoxysilane, and the like;

examples of the compound having a group represented by the above formula (3-3) include 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 3- (meth) acryloyloxypropylmethyldimethoxysilane, 3- (meth) acryloyloxypropylmethyldiethoxysilane, 4- (meth) acryloyloxybutyltrimethoxysilane and the like. In the present specification, "(meth) acrylic acid" means a meaning including "acrylic acid" and "methacrylic acid".

The content ratio of the structural unit (I) in the polymer (S) is preferably 5% by mass or more, more preferably 7% by mass or more, and still more preferably 10% by mass or more, relative to the total structural units constituting the polymer (S). The content ratio of the structural unit (I) is preferably 50% by mass or less, more preferably 45% by mass or less, and still more preferably 40% by mass or less, relative to the total structural units constituting the polymer (S). When the content ratio of the structural unit (I) is in the above range, it is preferable that the heat resistance and chemical resistance of the obtained cured film are sufficiently improved, the low dielectric constant property is improved, and the coating film exhibits better resolution.

Other structural units

The polymer (S) may further contain a structural unit other than the structural unit (I) (hereinafter, also referred to as "other structural unit"). Examples of the other structural unit include a structural unit (II) having at least one of an oxetanyl group and an oxetanyl group, a structural unit (III) having an acid group, and the like. In the present specification, an oxetanyl group and an oxetanyl group are also included and referred to as an "epoxy group".

Structural Unit (II)

When the polymer (S) contains the structural unit (II), the film is preferably improved in resolution and adhesiveness. Further, the epoxy group functions as a crosslinkable group, and thus a cured film having high chemical resistance and suppressed deterioration for a long period of time can be preferably formed. The structural unit (II) is preferably a structural unit derived from an unsaturated monomer having an epoxy group, and more specifically, is preferably a structural unit represented by the following formula (5).

[ solution 6]

(in the formula (5), R²⁰Is a monovalent radical having an oxetanyl or oxetanyl group. R^AIs hydrogen atom, methyl, hydroxymethyl, cyano or trifluoromethyl. X¹Is a single bond or a divalent linking group)

In the formula (5), as R²⁰Examples thereof include an oxetanyl group, a 3, 4-epoxycyclohexyl group, and a 3, 4-epoxytricyclo [5.2.1.0 ]^2，6]Decyl, 3-ethyloxetanyl, and the like.

As X¹The divalent linking group of (3) is preferably an alkanediyl group such as a methylene group, an ethylene group, or a 1, 3-propanediyl group.

Specific examples of the monomer having an epoxy group include: glycidyl (meth) acrylate, 3, 4-epoxycyclohexyl (meth) acrylate, 3, 4-epoxycyclohexylmethyl (meth) acrylate, 2- (3, 4-epoxycyclohexyl) ethyl (meth) acrylate, 3, 4-epoxytricyclo [5.2.1.0 ] meth) acrylate^2，6]Decyl ester; (3-Methylooxetan-3-yl) methyl (meth) acrylate, (3-ethyloxetan-3-yl) meth (acrylate), (oxetan-3-yl (meth) acrylate) Methyl ester, (meth) acrylic acid (3-ethyl oxetan-3-yl) methyl ester, and the like.

The content ratio of the structural unit (II) in the polymer (S) is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 20% by mass or more, relative to the total structural units constituting the polymer (S). The content ratio of the structural unit (II) is preferably 65% by mass or less, more preferably 60% by mass or less, and further preferably 55% by mass or less, relative to the entire structural units constituting the polymer (S). When the content ratio of the structural unit (II) is in the above range, the coating film preferably exhibits better resolution and the heat resistance and chemical resistance of the obtained cured film are sufficiently improved.

Structural Unit (III)

The polymer (S) preferably further comprises a structural unit (III) having an acid group. The structural unit (III) can improve the solubility of the polymer (S) in an alkali developer (alkali-soluble) or the hardening reactivity. In the present specification, the term "alkali-soluble" means that the compound can be dissolved or swelled in an aqueous alkali solution such as a 2.38 mass% aqueous tetramethylammonium hydroxide solution.

The structural unit (III) is not particularly limited as long as it has an acid group, and is preferably at least one selected from the group consisting of a structural unit having a carboxyl group, a structural unit having a sulfonic acid group, a structural unit having a phenolic hydroxyl group, and a maleimide unit. In the present specification, the term "phenolic hydroxyl group" refers to a hydroxyl group directly bonded to an aromatic ring (e.g., benzene ring, naphthalene ring, anthracene ring, etc.).

The structural unit (III) is preferably a structural unit derived from an unsaturated monomer having an acid group. Specific examples of the unsaturated monomer having an acid group include unsaturated monocarboxylic acids such as (meth) acrylic acid, crotonic acid, and 4-vinylbenzoic acid; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid, and itaconic acid; examples of the monomer constituting the structural unit having a sulfonic acid group include vinylsulfonic acid, (meth) allylsulfonic acid, styrenesulfonic acid, (meth) acryloyloxyethylsulfonic acid, and the like; examples of the monomer constituting the structural unit having a phenolic hydroxyl group include 4-hydroxystyrene, o-isopropenylphenol, m-isopropenylphenol, p-isopropenylphenol, hydroxyphenyl (meth) acrylate, and the like. In addition, as a monomer constituting the structural unit (III), maleimide may also be used.

From the viewpoint of imparting good solubility in an alkaline developing solution, the content ratio of the structural unit (III) in the polymer (S) is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 5% by mass or more, relative to the total structural units constituting the polymer (S). On the other hand, if the content ratio of the structural unit (III) is too high, the difference in solubility in an alkali developing solution between the exposed portion and the unexposed portion may be small, and it may be difficult to obtain a good pattern shape. From this viewpoint, the content ratio of the structural unit (III) is preferably 40% by mass or less, more preferably 35% by mass or less, and still more preferably 30% by mass or less with respect to the entire structural units constituting the polymer (S).

The other structural units include structural units derived from at least one monomer selected from the group consisting of alkyl (meth) acrylates, (meth) acrylates having an alicyclic structure, (meth) acrylates having an aromatic ring structure, aromatic vinyl compounds, N-substituted maleimide compounds, vinyl compounds having a heterocyclic structure, conjugated diene compounds, nitrogen-containing vinyl compounds, and unsaturated dicarboxylic acid dialkyl ester compounds. By introducing these structural units into the polymer, the glass transition temperature of the polymer component can be adjusted, and the pattern shape and chemical resistance of the cured film obtained can be improved.

Specific examples of the monomer include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-lauryl (meth) acrylate, and n-stearyl (meth) acrylate;

as having an alicyclic ringExamples of the (meth) acrylic acid ester having a structure include cyclohexyl (meth) acrylate, 2-methylcyclohexyl (meth) acrylate, and tricyclo [5.2.1.0 ] meth (acrylic acid)^2，6]Decan-8-yl ester, tricyclo [5.2.1.0 ] meth (acrylic acid)^2，5]Decan-8-yloxyethyl ester, isobornyl (meth) acrylate, and the like;

examples of the (meth) acrylate having an aromatic ring structure include phenyl (meth) acrylate, benzyl (meth) acrylate, and the like;

examples of the aromatic vinyl compound include styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, α -methylstyrene, 2, 4-dimethylstyrene, 2, 4-diisopropylstyrene, 5-tert-butyl-2-methylstyrene, divinylbenzene, trivinylbenzene, tert-butoxystyrene, vinylbenzyldimethylamine, (4-vinylbenzyl) dimethylaminoethyl ether, N-dimethylaminoethylstyrene, N-dimethylaminomethylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2-tert-butylstyrene, 3-tert-butylstyrene, 4-tert-butylstyrene, diphenylethylene, and mixtures thereof, Vinylnaphthalene, vinylpyridine, and the like;

examples of the N-substituted maleimide compound include N-cyclohexylmaleimide, N-cyclopentylmaleimide, N- (2-methylcyclohexyl) maleimide, N- (4-ethylcyclohexyl) maleimide, N- (2, 6-dimethylcyclohexyl) maleimide, N-norbornylmaleimide, N-tricyclodecylmaleimide, N-adamantylmaleimide, N-phenylmaleimide, N- (2-methylphenyl) maleimide, N- (4-ethylphenyl) maleimide, N- (2, 6-dimethylphenyl) maleimide, N-cyclopentylmaleimide, N- (2-methylcyclohexyl) maleimide, N- (4-ethylcyclohexyl) maleimide, N-norbornylmaleimide, N-tricyclodecylmaleimide, N-adamantylmaleimide, N-phenylmaleimide, N- (2-methylphenyl) maleimide, N- (4-ethylphenyl) maleimide, N- (2, 6-dimethylphenyl) maleimide, N-cyclohexylmaleimide, N- (4-ethylcyclohexyl) maleimide, N- (2-ethylcyclohexyl) maleimide, N- (4-ethylcyclohexyl) maleimide, N- (2-cyclohexylmaleimide, N-phenylmaleimide, N- (4-cyclohexylmaleimide, N-phenylmaleimide, N- (2-phenylmaleimide, N, N-benzylmaleimide, N-naphthylmaleimide, etc.;

examples of the vinyl compound having a heterocyclic ring structure include tetrahydrofurfuryl (meth) acrylate, tetrahydropyranyl (meth) acrylate, 5-ethyl-1, 3-dioxan-5-ylmethyl (meth) acrylate, 5-methyl-1, 3-dioxan-5-ylmethyl (meth) acrylate, (2-methyl-2-ethyl-1, 3-dioxolan-4-yl) methyl (meth) acrylate, 2- (meth) acryloyloxymethyl-1, 4, 6-trioxaspiro [4, 6] undecane, (meth) acrylate (. gamma. -butyrolactone-2-yl) ester, (meth) acrylate glycerol carbonate, (meth) acrylate (. gamma. -lactam-2-yl) ester, and the like, N- (meth) acryloyloxyethylhexahydrophthalimide, etc.;

examples of the conjugated diene compound include 1, 3-butadiene, isoprene, and the like;

examples of the nitrogen-containing vinyl compound include (meth) acrylonitrile, (meth) acrylamide and the like;

examples of the unsaturated dicarboxylic acid dialkyl ester compound include diethyl itaconate. In addition to the above, examples of the monomer constituting the other structural unit include monomers such as vinyl chloride, vinylidene chloride, and vinyl acetate.

From the viewpoint of adjusting the glass transition temperature of the polymer component to suppress melt flow during thermal curing, the polymer (S) preferably contains, as a structural unit other than the structural unit (II) and the structural unit (III), a structural unit derived from at least one monomer selected from the group consisting of an alkyl (meth) acrylate, a (meth) acrylate having an alicyclic structure, and a (meth) acrylate having an aromatic ring structure.

From the viewpoint of appropriately increasing the glass transition temperature of the polymer (S), the content ratio of the structural unit other than the structural unit (II) and the structural unit (III) is preferably 5% by mass or more, and more preferably 10% by mass or more, relative to the total structural units constituting the polymer (S). The content ratio of the structural unit is preferably 50% by mass or less, more preferably 40% by mass or less, relative to the total structural units constituting the polymer (S).

The polymer (S) can be produced by a conventional method such as radical polymerization in an appropriate solvent in the presence of a polymerization initiator or the like, using an unsaturated monomer capable of introducing each of the above-mentioned structural units. Examples of the polymerization initiator include azo compounds such as 2, 2 ' -azobis (isobutyronitrile), 2 ' -azobis (2, 4-dimethylvaleronitrile), and dimethyl 2, 2 ' -azobis (isobutyrate). The proportion of the polymerization initiator used is preferably 0.01 to 30 parts by mass with respect to 100 parts by mass of the total amount of the monomers used in the reaction. Examples of the polymerization solvent include alcohols, ethers, ketones, esters, and hydrocarbons. The amount of the polymerization solvent used is preferably such that the total amount of the monomers used in the reaction is 0.1 to 60% by mass based on the total amount of the reaction solution.

In the polymerization, the reaction temperature is usually from 30 ℃ to 180 ℃. The reaction time varies depending on the kinds of the polymerization initiator and the monomer and the reaction temperature, and is usually 0.5 to 10 hours. The polymer obtained by the polymerization reaction can be used in the preparation of the radiation-sensitive composition in a state of being dissolved in the reaction solution, and can also be used in the preparation of the radiation-sensitive composition after being separated from the reaction solution. The polymer can be isolated by a conventional separation method such as a method of injecting the reaction solution into a large amount of a poor solvent and drying the precipitate obtained thereby under reduced pressure, a method of distilling off the reaction solution under reduced pressure using an evaporator, or the like.

When the [ a ] polymer component contains the polymer (S), the [ a ] polymer component may be composed of only the polymer (S) having the structural unit (I) or may contain a polymer having no structural unit (I) together with the polymer (S) as long as the [ a ] polymer component contains the structural unit (I). For example, when the polymer component [ a ] includes the structural unit (I), the structural unit (II), and the structural unit (III), the same polymer may have all of the structural unit (I), the structural unit (II), and the structural unit (III), or at least a part of the structural unit (II) and the structural unit (III) may be included in a polymer different from the polymer having the structural unit (I). In addition, when two or more different polymers have the structural unit (I), the structural unit (II), and the structural unit (III), it is preferable that the content ratio of each structural unit contained in the [ a ] polymer component satisfies the above range. In view of reducing the number of components constituting the radiation-sensitive composition and obtaining the effect of improving development adhesion and chemical resistance, the [ a ] polymer component is preferably a polymer containing a structural unit (I), a structural unit (II), and a structural unit (III). Each polymer constituting the polymer component is preferably an alkali-soluble resin.

The weight average molecular weight (Mw) of the polymer (S) in terms of polystyrene obtained by Gel Permeation Chromatography (GPC) is preferably 2000 or more. When Mw is 2000 or more, it is preferable that the heat resistance and chemical resistance are sufficiently high and a cured film having good developability can be obtained. Mw is more preferably 5000 or more, further preferably 6000 or more, and particularly preferably 7000 or more. In addition, Mw is preferably 50000 or less, more preferably 30000 or less, further preferably 20000 or less, and particularly preferably 15000 or less, from the viewpoint of improving film formability.

The molecular weight distribution (Mw/Mn) represented by the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is preferably 4.0 or less, more preferably 3.0 or less, and still more preferably 2.5 or less. When the [ a ] polymer component contains two or more polymers, the Mw and Mw/Mn of each polymer preferably satisfy the above ranges.

(siloxane Polymer)

The siloxane polymer is not particularly limited as long as it can form a cured film by hydrolytic condensation. The siloxane polymer is preferably a polymer obtained by hydrolyzing a hydrolyzable silane compound represented by the following formula (6).

[ solution 7]

(in the formula (6), R²¹Is a non-hydrolyzable monovalent radical. R²²Is an alkyl group having 1 to 4 carbon atoms. r is an integer of 0 to 3. Wherein, when R is 2 or 3, a plurality of R in the formula²¹Are the same group as each other or different groups. When R is 0 to 2, a plurality of R in the formula²²Being the same radical or different radicals from each other)

As R²¹Examples thereof include C1-20 alkyl, C2-20 alkenyl, C6-E20 aryl group, 7-20 aralkyl group, group having (meth) acryloyl group, and group having epoxy group.

As R²²Examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. Among these, R is highly hydrolyzable²²Preferably methyl or ethyl.

r is preferably 0 to 2, more preferably 0 or 1, and still more preferably 1.

Specific examples of the monomer constituting the siloxane polymer include silane compounds having four hydrolyzable groups, such as tetramethoxysilane, tetraethoxysilane, triethoxymethoxy silane, tetrabutoxy silane, tetraphenoxysilane, tetrabenzyloxy silane, tetra-n-propoxysilane, and the like;

examples of the silane compound having three hydrolyzable groups include methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltributoxysilane, phenyltrimethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltributoxysilane, butyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, and the like;

examples of the silane compound having two hydrolyzable groups include dimethyldimethoxysilane, diphenyldimethoxysilane, and the like;

examples of the silane compound having one hydrolyzable group include trimethylmethoxysilane and trimethylethoxysilane.

The siloxane polymer can be obtained by hydrolyzing and condensing one or more of the hydrolyzable silane compounds with water, preferably in the presence of an appropriate catalyst and an organic solvent. A hydrolyzable group (-OR) possessed by a hydrolyzable silane compound during hydrolysis and condensation reaction²²)1 mole of waterThe use ratio is preferably 0.1 to 3 moles, more preferably 0.2 to 2 moles, and still more preferably 0.5 to 1.5 moles. By using such an amount of water, the reaction rate of the hydrolytic condensation can be optimized.

Examples of the catalyst used in the hydrolysis and condensation reaction include acids, alkali metal compounds, organic bases, titanium compounds, zirconium compounds, and the like. The amount of the catalyst to be used varies depending on the kind of the catalyst, reaction conditions such as temperature, and the like, and is appropriately set, and is preferably 0.0001 to 0.2 mol, and more preferably 0.0005 to 0.1 mol, based on 1 mol of the hydrolyzable silane compound.

Examples of the organic solvent used in the hydrolysis and condensation reaction include hydrocarbons, ketones, esters, ethers, and alcohols. Of these, it is preferable to use a water-insoluble or hardly water-soluble organic solvent, and examples thereof include ethylene glycol monoalkyl ether acetate, diethylene glycol dialkyl ether, propylene glycol monoalkyl ether acetate, propionate compounds, and the like. The use ratio of the organic solvent is preferably 10 to 10,000 parts by mass, more preferably 50 to 1,000 parts by mass, based on 100 parts by mass of the total of the hydrolyzable silane compounds used in the reaction.

In the hydrolysis and condensation reaction, the reaction temperature is preferably 130 ℃ or lower, more preferably 40 to 100 ℃. The reaction time is preferably 0.5 to 24 hours, more preferably 1 to 12 hours. In the reaction, the mixture may be stirred or may be refluxed. After the hydrolytic condensation reaction, a dehydrating agent may be added to the reaction solution, followed by evaporation (evaporation) to remove water and the formed alcohol from the reaction system.

The silicone polymer preferably has a weight average molecular weight (Mw) of 500 or more in terms of polystyrene obtained by GPC. When Mw is 500 or more, a cured film having sufficiently high heat resistance and solvent resistance and exhibiting good developability is preferably obtained. More preferably, Mw is 1000 or more. Further, Mw is preferably 10000 or less, more preferably 5000 or less, from the viewpoint of improving film formability and from the viewpoint of suppressing a decrease in radiation sensitivity. The molecular weight distribution (Mw/Mn) is preferably 4.0 or less, more preferably 3.0 or less, and still more preferably 2.5 or less.

The content ratio of the [ a ] polymer component is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 50% by mass or more, relative to the total amount of solid components contained in the radiation-sensitive composition. The content ratio of the polymer component to the total amount of solid components contained in the radiation-sensitive composition is preferably 99 mass% or less, and more preferably 95 mass% or less. By setting the content ratio of the polymer component in the above range, a cured film having sufficiently high heat resistance and chemical resistance and exhibiting good developability and transparency can be obtained.

[ B ] ortho ester Compound

[B]The orthoester compound being an OR having three radicals³⁰"(wherein R is³⁰A monovalent hydrocarbon group) to the same carbon, by the general formula: r³¹-C(OR³⁰)₃As indicated. Here, R³¹Is a hydrogen atom or a monovalent organic group. [ B ]]The orthoester compound exhibits water absorption in the presence of an acid and becomes an ester after hydrolysis. By containing such an orthoester compound in a radiation-sensitive composition together with a silicon-containing polymer, self-C is utilized]The acid generated by the photoacid generator (in other words, irradiation of radiation) exhibits the water-absorbing action of the orthoester compound, and the water-absorbing action of the orthoester compound improves the development adhesion of the coating film. The orthoester compound is preferably stable to an alkali developing solution, is hydrophobic, and has little influence on an unexposed portion (for example, influence on sensitivity).

The group "-OR" possessed by the orthoester compound³⁰Examples of the "substituent" include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, n-pentoxy group, phenoxy group, and methylphenyl group. Among these, the group "-OR" possessed by the orthoester compound³⁰"is preferably an alkoxy group, and more preferably an alkoxy group having 1 to 4 carbon atoms. Further, the orthoester compound has three groups "R³⁰"are the same radicals as or different from each otherAnd (4) a base.

As R³¹Examples thereof include a hydrogen atom, a monovalent chain hydrocarbon group, a halogenated chain hydrocarbon group in which at least one hydrogen atom of the chain hydrocarbon group is substituted with a halogen atom, and a monovalent aromatic ring group. In these, R³¹Preferably a hydrogen atom, a monovalent chain hydrocarbon group or a monovalent aromatic ring group, and specifically includes a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms.

Specific examples of [ B ] orthoester compounds include: triethyl orthochloroacetate, trimethyl orthoformate, triethyl orthoformate, tripropyl orthoformate, triisopropyl orthoformate, tributyl orthoformate, diethylphenyl orthoformate, trimethyl orthoacetate, triethyl orthodichloroacetate, trimethyl orthobutyrate, triethyl orthobutyrate, trimethyl orthopropionate, triethyl orthopropionate, trimethyl pivalate, triethyl orthovalerate, trimethyl orthoisobutyrate, trimethyl orthobenzoate, triethyl orthobenzoate, and the like.

Among the [ B ] orthoester compounds, a compound represented by the following formula (2) can be preferably used.

R³³-C-(OR³²)₃...(2)

(in the formula (2), R³²Is C1-4 alkyl or phenyl. R³³Is a hydrogen atom, a C1-4 monovalent chain hydrocarbon group or a C6-12 monovalent aromatic ring group. Three of R in the formula³²Being the same radical or different radicals from each other)

In the formula (2), R³²The alkyl group (b) may be linear or branched. R is a group having a high effect of improving the development adhesion of a coating film and having a small influence on sensitivity³²Preferably methyl, ethyl or phenyl, more preferably methyl or ethyl.

R³³The chain hydrocarbon group(s) is preferably a C1-4 chain or branched alkyl group. As R³³Examples of the aromatic ring group in (b) include a phenyl group, a methylphenyl group, a dimethylphenyl group, an ethylphenyl group and a naphthyl group.

The effect of improving the development adhesion of the coating film is highIn the above, R³³Preferred is a monovalent aromatic ring group, and particularly preferred is a phenyl group.

In order to further improve the development adhesion of the coating film, [ B ] is]As the ortho ester compound, a compound having an aromatic ring group can be preferably used. Specific examples of the compound having an aromatic ring group include R in the above formula (2)³²And R³³At least one of which is an aromatic ring group. Furthermore, in [ B]When the orthoester compound has an aromatic ring, the orthoester compound is likely to remain in the film due to the increase in hydrophobicity of the orthoester compound, and it is considered that this is caused by sufficient dehydration of the end portion of the unexposed portion.

Specific examples of the orthoester compound having an aromatic ring group include trimethyl orthobenzoate, triethyl orthobenzoate, diethylphenyl orthoformate and the like. Among these, trimethyl orthobenzoate and triethyl orthobenzoate are particularly preferable in terms of high effect of improving the development adhesion of the coating film and maintaining the sensitivity more favorably.

[B] The orthoester compound preferably has a higher boiling point than the prebaking temperature. By using an orthoester compound having a sufficiently high boiling point with respect to the prebaking temperature, the development adhesion of the coating film can be further improved. Specifically, the boiling point of the [ B ] orthoester compound is preferably 105 ℃ or higher, more preferably 110 ℃ or higher, and still more preferably 115 ℃ or higher. In addition, in the case where the boiling point of the [ B ] orthoester compound is sufficiently high with respect to the prebaking temperature, volatilization of the [ B ] orthoester compound at the prebaking is suppressed, and the orthoester compound is likely to remain in the film even after the prebaking, and thus it is considered that this is caused by sufficient dehydration of the end portions of the unexposed portions.

Specific examples of [ B ] orthoester compounds having a boiling point of 105 ℃ or higher include: triethyl orthoformate, tripropyl orthoformate, tributyl orthoformate, trimethyl orthoacetate, triethyl orthodichloroacetate, trimethyl orthobutyrate, trimethyl orthopropionate, triethyl orthopropionate, trimethyl orthovalerate, trimethyl orthobenzoate, triethyl orthobenzoate, and the like. Further, in the present specification, the boiling point is a value at one atmospheric pressure.

In the radiation-sensitive composition, the content of the [ B ] orthoester compound is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, further preferably 1 part by mass or more, and particularly preferably 2 parts by mass or more, relative to 100 parts by mass of the [ a ] polymer component. The content of the [ B ] orthoester compound is preferably 30 parts by mass or less, more preferably 25 parts by mass or less, and still more preferably 20 parts by mass or less, relative to 100 parts by mass of the [ a ] polymer component. When the content of the [ B ] orthoester compound is 0.1 parts by mass or more, it is preferable that the effect of improving the development adhesion of the coating film by allowing the [ B ] orthoester compound to be present in the film is sufficiently obtained. When the content of the [ B ] orthoester compound is 30 parts by mass or less, it is preferable that the decrease in sensitivity due to the [ B ] orthoester compound is suppressed.

[ C ] photoacid generators

The photoacid generator is not particularly limited as long as it is a compound that generates an acid upon irradiation with radiation. Examples of the photoacid generator include: oxime sulfonate compounds, onium salts, sulfonimide compounds, halogen-containing compounds, diazomethane compounds, sulfone compounds, sulfonate compounds, carboxylate compounds, quinone diazide compounds.

Specific examples of the oxime sulfonate compound, onium salt, sulfonimide compound, halogen-containing compound, diazomethane compound, sulfone compound, sulfonate compound and carboxylate compound include compounds described in paragraphs 0078 to 0106 of Japanese patent laid-open No. 2014-157252, compounds described in International publication No. 2016/124493, and the like. As the photoacid generator, at least one selected from the group consisting of oxime sulfonate compounds and sulfonimide compounds is preferably used from the viewpoint of radiation sensitivity.

The oxime sulfonate compound is preferably a compound having a sulfonate group represented by the following formula (7).

[ solution 8]

(in the formula (7), R²³Is a monovalent hydrocarbon group, or a monovalent group in which a part or all of hydrogen atoms contained in the hydrocarbon group are substituted with a substituent. "+" indicates a bond)

In the formula (7), as R²³Examples of the monovalent hydrocarbon group include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 4 to 12 carbon atoms, and an aryl group having 6 to 20 carbon atoms. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a pendant oxy group, a halogen atom, and the like.

Examples of oxime sulfonate compounds include: (5-propylsulfonyloxyimino-5H-thiophen-2-ylidene) - (2-methylphenyl) acetonitrile, (5-octylsulfonyloxyimino-5H-thiophen-2-ylidene) - (2-methylphenyl) acetonitrile, (camphorsulfonyloxyimino-5H-thiophen-2-ylidene) - (2-methylphenyl) acetonitrile, (5-p-toluenesulfonyloxyimino-5H-thiophen-2-ylidene) - (2-methylphenyl) acetonitrile, [2- [2- (4-methylphenylsulfonyloxyimino) ] -2, 3-dihydrothiophen-3-ylidene ] -2- (2-methylphenyl) acetonitrile, and mixtures thereof, 2- (octylsulfonyloxyimino) -2- (4-methoxyphenyl) acetonitrile, a compound described in International publication No. 2016/124493, and the like. Examples of commercially available oxime sulfonate compounds include Irgacure (PAG 121) manufactured by BASF corporation.

Examples of the sulfonimide compound include: n- (trifluoromethylsulfonyloxy) succinimide, N- (camphorsulfonyloxy) succinimide, N- (4-methylphenylsulfonyloxy) succinimide, N- (2-trifluoromethylphenylsulfonyloxy) succinimide, N- (4-fluorophenylsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (camphorsulfonyloxy) phthalimide, N- (2-trifluoromethylphenylsulfonyloxy) phthalimide, N- (2-fluorophenylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) diphenylmaleimide, N- (camphorsulfonyloxy) diphenylmaleimide, N- (4-methylphenylsulfonyloxy) diphenylmaleimide, N- (N-methyl-sulfonyloxy) diphenylmaleimide, N- (N-methyl-phenylsulfonyloxy) diphenylmaleimide, N- (4-methyl-phenylsulfonyloxy) phthalimide, N- (4-phenylsulfonyloxy) phthalimide, and a, 1, 8-naphthalimide trifluoromethanesulfonate.

As the photoacid generator, one or more of an oxime sulfonate compound, an onium salt, a sulfonimide compound, a halogen-containing compound, a diazomethane compound, a sulfone compound, a sulfonate compound, and a carboxylate compound may be used in combination with a quinonediazide compound. In addition, a quinone diazide compound may be used alone.

The quinone diazide compound is a radiation-sensitive acid generator that generates a carboxylic acid by irradiation with radiation. Examples of the quinonediazide compound include a condensate of a phenolic compound or an alcoholic compound (hereinafter, also referred to as a "core") and an o-naphthoquinonediazide compound. Among these, the quinone diazide compound used is preferably a condensate of a compound having a phenolic hydroxyl group as a parent nucleus and an o-naphthoquinone diazide compound. Specific examples of the mother nucleus include compounds described in paragraphs 0065 to 0070 of Japanese patent laid-open No. 2014-186300.

Specific examples of the quinonediazide compound include compounds selected from the group consisting of 4, 4 '-dihydroxydiphenylmethane, 2, 3, 4, 2', 4 '-pentahydroxybenzophenone, tris (p-hydroxyphenyl) methane, 1, 1, 1-tris (p-hydroxyphenyl) ethane, 1, 1-bis (4-hydroxyphenyl) -1-phenylethane, 1, 3-bis [1- (4-hydroxyphenyl) -1-methylethyl ] benzene, 1, 4-bis [1- (4-hydroxyphenyl) -1-methylethyl ] benzene, 4, 6-bis [1- (4-hydroxyphenyl) -1-methylethyl ] -1, 3-dihydroxybenzene and 4, 4' - [1- [4- [1- [ 4-hydroxyphenyl ] -1-methylethyl ] phenyl ] ethylidene ] bisphenol The ester compound of (1) or (2) a compound containing a phenolic hydroxyl group and 1, 2-naphthoquinonediazide-4-sulfonyl chloride or 1, 2-naphthoquinonediazide-5-sulfonyl chloride.

In the radiation-sensitive composition, the content of the [ C ] photoacid generator is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, relative to 100 parts by mass of the [ A ] polymer component. The content of the [ C ] photoacid generator is preferably 20 parts by mass or less, and more preferably 15 parts by mass or less, based on 100 parts by mass of the [ A ] polymer component. When the content of the [ C ] photoacid generator is 0.05 parts by mass or more, acid is sufficiently generated by irradiation with radiation, and the difference in solubility in an alkaline solution between the irradiated portion and the non-irradiated portion of the radiation can be sufficiently increased. This enables favorable pattern formation. Further, the amount of the acid to be reacted with the [ A ] polymer component can be increased, and the heat resistance and the solvent resistance can be sufficiently ensured. On the other hand, it is preferable to set the content of the [ C ] photoacid generator to 20 parts by mass or less, because the amount of unreacted photoacid generator after exposure can be sufficiently reduced, and the deterioration of developability due to the residue of the [ C ] photoacid generator can be suppressed.

Here, in the case where water absorption occurs at the end of the unexposed portion during development, the group R in the formula (1) existing at the end of the unexposed portion¹The silanol group is changed, and thus hydrophilicity at the end of the unexposed portion is increased, and development adhesion of the coating film is lowered. In order to suppress such a decrease in development adhesion, it is conceivable to blend a hydrophobic additive in the radiation-sensitive composition or to introduce a structural unit derived from a hydrophobic monomer into the polymer component. However, when the hydrophobicity of the coating film is increased, the developing solubility at the exposed portion tends to be lowered, or the sensitivity tends to be lowered. In contrast, in the present disclosure, the composition is prepared by blending [ B ] in a radiation-sensitive composition using a silicon-containing polymer]The ortho-ester compound can improve the developing adhesion of the coating film. In addition, a Post-Coating Delay (PCD) margin, which is a margin of time from the pre-baking to the Exposure, and a Post-Exposure Delay (PED) margin, which is a margin of time from the Exposure to the development, can be sufficiently secured.

< other ingredients >

The radiation-sensitive composition of the present disclosure may further contain components other than the above (hereinafter, also referred to as "other components") in addition to the above-described [ a ] polymer component, [ B ] orthoester compound and [ C ] photoacid generator.

(solvent)

The radiation-sensitive composition of the present disclosure is a liquid composition in which the components [ A ] polymer component, [ B ] orthoester compound, [ C ] photoacid generator, and optionally blended are preferably dissolved or dispersed in a solvent. The solvent used is preferably an organic solvent that dissolves each component formulated in the radiation-sensitive composition and does not react with each component.

Specific examples of the solvent include: alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; esters such as ethyl acetate, butyl acetate, ethyl lactate, γ -butyrolactone, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, etc.; ethers such as ethylene glycol monobutyl ether, propylene glycol monomethyl ether, ethylene glycol ethyl methyl ether, dimethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, and the like; amides such as dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene. Among these, the solvent preferably contains at least one selected from the group consisting of ethers and esters, and more preferably at least one selected from the group consisting of ethylene glycol alkyl ether acetates, diethylene glycols, propylene glycol monoalkyl ethers, and propylene glycol monoalkyl ether acetates.

(Tight-lock auxiliary)

The adhesion promoter is a component for improving the adhesion between a cured film formed using the radiation-sensitive composition and a substrate. As the adhesion promoter, a functional silane coupling agent having a reactive functional group can be preferably used. Examples of the reactive functional group of the functional silane coupling agent include a carboxyl group, (meth) acryloyl group, epoxy group, vinyl group, and isocyanate group.

Specific examples of the functional coupling agent include: trimethoxysilylbenzoic acid, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, etc.

When the adhesion promoter is blended in the radiation-sensitive composition, the content thereof is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, based on 100 parts by mass of the [ a ] polymer component.

(acid diffusion controller)

The acid diffusion controller is a component that controls the diffusion length of the acid generated from the [ C ] photoacid generator by exposure. By blending an acid diffusion controller in the radiation-sensitive composition of the present disclosure, the diffusion length of the acid can be appropriately controlled, and the pattern developability can be improved. Further, it is preferable to add an acid diffusion controller in order to improve the development adhesion and to improve the chemical resistance.

The acid diffusion controller may be optionally selected from basic compounds used in chemically amplified resists. Examples of the basic compound include fatty acid amines, aromatic amines, heterocyclic amines, quaternary ammonium hydroxides, quaternary ammonium carboxylates, and the like. Specific examples of the basic compound include compounds described in paragraphs 0128 to 0147 of Japanese patent laid-open publication No. 2011-232632, and the like. As the acid diffusion controller, at least one selected from the group consisting of aromatic amines and heterocyclic amines can be preferably used.

Examples of the aromatic amine and heterocyclic amine include: aniline derivatives such as aniline, N-methylaniline, N-ethylaniline, N-propylaniline, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, ethylaniline, propylaniline, trimethylaniline, 2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2, 4-dinitroaniline, 2, 6-dinitroaniline, 3, 5-dinitroaniline, and N, N-dimethyltoluidine; imidazole derivatives such as imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, 2-phenylbenzimidazole and triphenylimidazole; pyrrole derivatives such as pyrrole, 2H-pyrrole, 1-methylpyrrole, 2, 4-dimethylpyrrole, 2, 5-dimethylpyrrole and N-methylpyrrole; pyridine derivatives such as pyridine, picoline, ethylpyridine, propylpyridine, butylpyridine, 4- (1-butylpentyl) pyridine, lutidine, collidine, triethylpyridine, phenylpyridine, 3-methyl-2-phenylpyridine, 3-methyl-4-phenylpyridine, 4-t-butylpyridine, diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine, dimethoxypyridine, 1-methyl-2-pyridone, 4-pyrrolidinylpyridine, 1-methyl-4-phenylpyridine, 2- (1-ethylpropyl) pyridine, aminopyridine, dimethylaminopyridine and nicotine, and the compounds described in Japanese patent application laid-open No. 2011-232632.

In the case where an acid diffusion controller is blended in a radiation-sensitive composition, the content ratio thereof is preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, per 100 parts by mass of the [ a ] polymer component, from the viewpoint of sufficiently obtaining the effect of improving chemical resistance by blending the acid diffusion controller. The content of the acid diffusion-controlling agent is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, per 100 parts by mass of the [ a ] polymer component.

As other components, in addition to the above, for example, there can be mentioned: a polyfunctional polymerizable compound (polyfunctional (meth) acrylate, etc.), a surfactant (fluorine-based surfactant, silicone-based surfactant, nonionic surfactant, etc.), a polymerization inhibitor, an antioxidant, a chain transfer agent, etc. The blending ratio of these components may be appropriately selected depending on each component within a range not impairing the effects of the present disclosure.

The concentration of the solid component of the radiation-sensitive composition of the present disclosure (the ratio of the total mass of the components excluding the solvent in the radiation-sensitive composition to the total mass of the radiation-sensitive composition) may be appropriately selected in consideration of viscosity, volatility, and the like. The solid content concentration of the radiation-sensitive composition is preferably in the range of 5 to 60% by mass. When the solid content concentration is 5% by mass or more, the film thickness of the coating film can be sufficiently ensured when the radiation-sensitive composition is applied to a substrate. When the solid content concentration is 60 mass% or less, the film thickness of the coating film is not excessively large, and the viscosity of the radiation-sensitive composition can be appropriately increased, so that good coatability can be ensured. The solid content concentration of the radiation-sensitive composition is more preferably 10 to 55% by mass, and still more preferably 12 to 50% by mass.

< cured film and method for producing the same >

The hardened film of the present disclosure is formed from the radiation-sensitive composition prepared in the manner described. The radiation-sensitive composition has high radiation sensitivity and excellent storage stability. Further, by using the radiation-sensitive composition, a pattern film which exhibits high adhesion to a substrate even after development and is excellent in chemical resistance can be formed. Therefore, the radiation-sensitive composition can be preferably used as a material for forming an interlayer insulating film, a planarizing film, a spacer, a protective film, a coloring pattern film for a color filter, a partition wall, a bank, or the like.

When a cured film is produced, a positive-type cured film can be formed depending on the type of the photosensitive agent by using the radiation-sensitive composition. The cured film can be produced using the radiation-sensitive composition, for example, by a method including the following steps 1 to 4.

(step 1) a step of forming a coating film using the radiation-sensitive composition.

(step 2) exposing at least a part of the coating film.

(step 3) a step of developing the exposed coating film.

(step 4) a step of heating the developed coating film.

Hereinafter, each step will be described in detail.

[ Process 1: coating Process)

In this step, the radiation-sensitive composition is applied to a film-forming surface (hereinafter also referred to as a "film-forming surface"), and preferably a solvent is removed by heat treatment (pre-baking) to form a coating film on the film-forming surface. The material of the film formation surface is not particularly limited. For example, in the case of forming an interlayer insulating film, the radiation-sensitive composition is applied to a substrate provided with a switching element such as a Thin Film Transistor (TFT) to form a coating film. Examples of the substrate include a glass substrate, a silicon substrate, and a resin substrate. A metal thin film may be formed on the surface of the substrate on which the coating film is formed according to the application, and various surface treatments such as Hexamethyldisilazane (HMDS) treatment may be performed.

Examples of the method for applying the radiation-sensitive composition include: spray method, roll coating method, spin coating method, slit die coating method, bar coating method, ink jet method, and the like. Among these coating methods, it is preferable to perform the coating by a spin coating method, a slit die coating method, or a bar coating method. The prebaking conditions vary depending on the kind and content ratio of each component of the radiation-sensitive composition, and are, for example, 0.5 to 10 minutes at 60 to 130 ℃. The film thickness of the formed coating film (i.e., the film thickness after the pre-baking) is preferably 0.1 to 12 μm. The radiation-sensitive composition applied to the film formation surface may be dried under reduced pressure (Vacuum Dry, VCD)) before prebaking.

[ step 2: exposure Process

In this step, at least a part of the coating film formed in the step 1 is irradiated with radiation. At this time, a cured film having a pattern can be formed by irradiating the coating film with radiation through a mask having a predetermined pattern. Examples of the radiation include charged particle beams such as ultraviolet rays, far ultraviolet rays, visible rays, X-rays, and electron beams. Of these, ultraviolet rays are preferable, and examples thereof include g rays (wavelength: 436nm) and i rays (wavelength: 365 nm). The exposure amount of the radiation is preferably 0.1J/m²～20,000J/m²。

[ step 3: development Process

In this step, the coating film irradiated with the radiation in the step 2 is developed. Specifically, the coating film irradiated with radiation in step 2 is subjected to positive development in which the irradiated portion of the radiation is removed by development with a developer. As the developer, for example, an aqueous solution of an alkali (alkaline compound) is cited. Examples of the base include sodium hydroxide, tetramethylammonium hydroxide, and the bases exemplified in paragraph [0127] of Japanese patent laid-open No. 2016-145913. The alkali concentration of the aqueous alkali solution is preferably 0.1 to 5% by mass from the viewpoint of obtaining appropriate developability. The developing method may be any suitable method such as a liquid coating method, a dipping method, a shaking dipping method, or a shower method. The development time also varies depending on the composition of the composition, and is, for example, 30 seconds to 120 seconds. Further, it is preferable that the patterned coating film is subjected to rinsing treatment by running water cleaning after the development step.

[ step 4: heating procedure

In this step, a treatment (post-baking) of heating the coating film developed in the step 3 is performed. The post baking can be performed using a heating device such as an oven or a hot plate. The post-baking conditions are, for example, heating temperatures of 120 to 250 ℃. For example, when the heat treatment is performed on a hot plate, the heating time is 5 to 40 minutes, and when the heat treatment is performed in an oven, the heating time is 10 to 80 minutes. In the manner described above, a hardened film having a target pattern can be formed on a substrate. The shape of the pattern of the cured film is not particularly limited, and examples thereof include a line and space pattern, a dot pattern, a hole pattern, and a lattice pattern.

< semiconductor device >

The semiconductor device of the present disclosure includes a cured film formed using the radiation-sensitive composition. The cured film is preferably an interlayer insulating film for insulating between wirings in the semiconductor element. The semiconductor element of the present disclosure can be manufactured using an existing method.

< display element >

The display element of the present disclosure includes a cured film formed using the radiation-sensitive composition. The display element includes the semiconductor element of the present disclosure, and thus has a cured film formed using the radiation-sensitive composition. The display element of the present disclosure may further include a planarization film formed on the TFT substrate as a cured film formed using the radiation-sensitive composition. Examples of the display element include a liquid crystal display element and an organic Electroluminescence (EL) display element.

[ examples ]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In the examples and comparative examples, "part(s)" and "%" are based on mass unless otherwise specified. In the present example, the weight average molecular weight (Mw) and the number average molecular weight of the polymer were measured by the following methods.

[ weight average molecular weight (Mw) and number average molecular weight (Mn) ]

The Mw and Mn of the polymer were measured by the following methods.

The measurement method: gel Permeation Chromatography (GPC) method

An apparatus: GPC-101 of Showa electrician

GPC column: GPC-KF-801, GPC-KF-802, GPC-KF-803, and GPC-KF-804 of Shimadzu GLC corporation were combined

The mobile phase: tetrahydrofuran (THF)

Column temperature: 40 deg.C

Flow rate: 1.0 mL/min

Sample concentration: 1.0% by mass

Sample injection amount: 100 μ L

The detector: differential refractometer

Standard substance: monodisperse polystyrene

[ monomer ]

The monomers used in the synthesis of the polymer are abbreviated as follows.

Monomer having group represented by the formula (1)

MPTMS: 3-methacryloxypropyltrimethoxysilane

MPTES: 3-methacryloxypropyltriethoxysilane

STMS: p-styryl trimethoxy silane

And (3) SDMS: p-styryl dimethoxy hydroxyl silane

STES: p-styryl triethoxy silane

Other monomers

AA: acrylic acid

MA: methacrylic acid

MI: maleimide

And (3) OXMA: OXE-30 (manufactured by Osaka organic chemical industries, Ltd.) methyl methacrylate (3-Ethyl oxetan-3-yl)

GMA: glycidyl methacrylate

ECHMA: 3, 4-epoxycyclohexylmethyl methacrylate

EDCPMA: methacrylic acid [3, 4-epoxy tricyclic (5.2.1.0)^2，6) Decan-9-yl]Esters

MMA: methacrylic acid methyl ester

ST: styrene (meth) acrylic acid ester

< Synthesis of Polymer (A) >

Synthesis example 1 Synthesis of Polymer (A-1)

A flask equipped with a cooling tube and a stirrer was charged with 24 parts of propylene glycol monomethyl ether, 39 parts of methyltrimethoxysilane and 18 parts of 3-methacryloxypropyltrimethoxysilane, and the mixture was heated to a solution temperature of 60 ℃. After the solution temperature reached 60 ℃, 0.1 part of formic acid and 19 parts of water were charged, and the temperature of the solution was raised to 75 ℃ while stirring slowly, and the temperature was maintained for 2 hours. After cooling to 45 ℃, 28 parts by mass of trimethyl orthoformate was added as a dehydrating agent, and stirred for 1 hour. Further, the solution temperature was adjusted to 40 ℃ and evaporation was carried out while keeping the temperature, whereby water and methanol produced in the hydrolytic condensation were removed, thereby obtaining a polymer solution containing the polymer (A-1). The polymer solution had a solid content concentration of 35% by mass, a weight average molecular weight (Mw) of the polymer (A-1) was 1,800, and a molecular weight distribution (Mw/Mn) was 2.2.

Synthesis example 2 Synthesis of Polymer (A-2)

Polymer (A-2) having the same solid content concentration, weight average molecular weight and molecular weight distribution as polymer (A-1) was obtained in the same manner as in Synthesis example 1, except that the monomers used were changed to phenyltrimethoxysilane 39 parts and 3-methacryloxypropyltrimethoxysilane 18 parts.

Synthesis example 3 Synthesis of Polymer (A-3)

A flask equipped with a cooling tube and a stirrer was charged with 10 parts of 2, 2' -azobis (2, 4-dimethylvaleronitrile) and 200 parts of diethylene glycol methylethyl ether. Then, 15 parts of 3-methacryloxypropyltrimethoxysilane, 10 parts of methacrylic acid, 20 parts of (3-ethyloxetan-3-yl) methyl methacrylate, 30 parts of glycidyl methacrylate and 25 parts of methyl methacrylate were charged, and after replacement with nitrogen gas, the temperature of the solution was raised to 70 ℃ with gentle stirring, and the temperature was maintained for 5 hours, thereby obtaining a polymer solution containing the polymer (A-3). The polymer solution had a solid content concentration of 34.0% by mass, the Mw of the polymer (A-3) was 10,500, and the molecular weight distribution (Mw/Mn) was 2.2.

Synthesis examples 4 to 12, comparative Synthesis example 1 and comparative Synthesis example 2 Synthesis of polymers (A-4) to (A-12), Polymer (CA-1) and Polymer (CA-2)

A polymer solution containing polymers (A-4) to (A-12), polymer (CA-1) and polymer (CA-2) having the same solid content concentration, weight average molecular weight and molecular weight distribution as those of polymer (A-3) was obtained in the same manner as in Synthesis example 3, except that the components were used in the same types and amounts (parts by mass) as shown in Table 1.

< preparation of radiation-sensitive composition >

The polymer (a), the orthoester compound (B), the photoacid generator (C), the additive (X), and the solvent (G) used for producing the radiation-sensitive composition are shown below.

Polymer (A)

A-1 to A-12: polymers (A-1) to (A-12) synthesized in Synthesis examples 1 to 12

CA-1 to CA-2: comparative Synthesis examples 1 and 2 Polymer (CA-1) and Polymer (CA-2)

Orthoester Compound (B)

B-1: trimethyl orthoformate

B-2: trimethyl orthoacetate

B-3: ethylorthoacetate

B-4: trimethyl orthobenzoate

B-5: benzoic acid triethyl ester

Photoacid Generator (C)

C-1: brilliant good solid (Irgacure) PAG121 (manufactured by BASF corporation)

C-2: OS-17 described in International publication No. 2016/124493

C-3: OS-25 described in International publication No. 2016/124493

Additive (X)

X-1: 3-glycidoxypropyltrimethoxysilane

X-2: 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane

X-3: 2-phenylbenzimidazoles

X-4: n- (tert-butoxycarbonyl) -2-phenylbenzimidazole

X-5: 4-methyl-2-phenylbenzimidazoles

Solvent (G)

G-1: diethylene glycol ethyl methyl ether

G-2: propylene glycol monomethyl ether

G-3: propylene glycol monomethyl ether acetate

< preparation of radiation-sensitive composition >

[ example 1]

In the polymer solution containing the polymer (A-1) obtained in Synthesis example 1, 5 parts of the orthoester compound (B-4), 1 part of the photoacid generator (C-2) and 5 parts of the additive (x-1) were mixed in an amount corresponding to 100 parts (solid content) of the polymer (A-1), and the mixture was heated at a temperature of 1: diethylene glycol ethyl methyl ether and propylene glycol monomethyl ether were added in a mass ratio of 1. Then, the mixture was filtered through a membrane filter having a pore size of 0.2 μm to prepare a radiation-sensitive composition.

Examples 2 to 20 and comparative examples 1 to 5

Radiation-sensitive compositions of examples 2 to 20 and comparative examples 1 to 5 were prepared in the same manner as in example 1, except that the components were used in the types and amounts (parts by mass) shown in Table 2.

< evaluation >

The radiation-sensitive compositions of examples 1 to 20 and comparative examples 1 to 5 were used to evaluate the following items by the methods described below. The evaluation results are shown in table 3.

[ radiation sensitivity ]

The radiation-sensitive composition was applied to a silicon substrate subjected to HMDS treatment at 60 ℃ for 60 seconds using a spinner, and then prebaked on a hot plate at 90 ℃ for 2 minutes to form a coating film having an average thickness of 3.0 μm. The coating film was irradiated with a predetermined amount of ultraviolet light by a mercury lamp through a pattern mask having a line and space pattern with a width of 10 μm. Subsequently, a developing treatment was performed at 25 ℃ for 60 seconds using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide as a developer, and then, rinsing was performed with ultrapure water for 1 minute. At this time, the minimum exposure amount capable of forming a line and space pattern having a width of 10 μm was measured. The measured value at the minimum exposure amount is less than 300J/m²The radiation sensitivity was evaluated to be good at 300J/m²In the above case, the radiation sensitivity was evaluated to be poor.

[ evaluation of PCD (post-coating retardation) margin ]

The radiation-sensitive composition was applied to a silicon substrate subjected to HMDS treatment at 60 ℃ for 60 seconds using a spinner, and then prebaked on a hot plate at 90 ℃ for 2 minutes to form a coating film having an average thickness of 3.0 μm. After the coating film was left at room temperature for 1 hour (the film was not left to stand in the following PED margin evaluation), a predetermined amount of ultraviolet light was irradiated to the coating film by a mercury lamp through a pattern mask having a line and space pattern with a width of 10 μm. After the ultraviolet irradiation, development treatment was performed at 25 ℃ for 60 seconds using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide as a developer, and then rinsing with running water was performed for 1 minute with ultrapure water. The series of operations was performed with changing the exposure amount, and the minimum exposure amount capable of forming a line-and-space pattern having a width of 10 μm was determined. The measurement value of the minimum exposure amount is compared with the measurement value of the [ radiation sensitivity ], and a case where the increase rate of the minimum exposure amount is less than 5% is determined as "AA", a case where the increase rate is 5% or more and less than 10% is determined as "a", a case where the increase rate is 10% or more and less than 20% is determined as "B", a case where the increase rate is 20% or more and less than 30% is determined as "C", and a case where the increase rate is 30% or more is determined as "D". PCD margin may be evaluated as good in the case of AA, a or B, and poor in the case of C or D.

[ evaluation of PED (post-exposure retardation) margin ]

The radiation-sensitive composition was applied to a silicon substrate subjected to HMDS treatment at 60 ℃ for 60 seconds using a spinner, and then prebaked on a hot plate at 90 ℃ for 2 minutes to form a coating film having an average thickness of 3.0 μm. The coating film was irradiated with a predetermined amount of ultraviolet light by a mercury lamp through a pattern mask having a line and space pattern with a width of 10 μm. After the ultraviolet-irradiated coating film was left at room temperature for 1 hour (the film was not left to stand in the PCD margin evaluation), the coating film was subjected to a development treatment at 25 ℃ for 60 seconds using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide as a developer, and then washed with ultrapure water for 1 minute. The series of operations was performed with changing the exposure amount, and the minimum exposure amount capable of forming a line-and-space pattern having a width of 10 μm was determined. The measurement value of the minimum exposure amount is compared with the measurement value of the [ radiation sensitivity ], and a case where the increase rate of the minimum exposure amount is less than 5% is determined as "AA", a case where the increase rate is 5% or more and less than 10% is determined as "a", a case where the increase rate is 10% or more and less than 20% is determined as "B", a case where the increase rate is 20% or more and less than 30% is determined as "C", and a case where the increase rate is 30% or more is determined as "D". In the case of AA, a or B, the PED margin can be evaluated as good, and in the case of C or D, the PED margin can be evaluated as poor.

[ evaluation of chemical resistance of cured film ]

The chemical resistance of the cured film was evaluated based on the degree of swelling caused by the stripping liquid. Applying a radiation-sensitive composition to silicon using a spinnerAfter the substrate was coated, it was prebaked at 90 ℃ for 2 minutes on a hot plate to form a coating film having an average film thickness of 3.0. mu.m. Then, 3000J/m was irradiated onto the entire surface of the substrate by using a proximity exposure apparatus ("MA-1200" (ghi ray mixing) manufactured by Canon corporation²After the light irradiation, the resultant was calcined (post-baked) in an oven heated to 230 ℃ for 30 minutes to form a cured film. The cured film thus obtained was immersed in an N-methyl-2-pyrrolidone solvent heated to 40 ℃ for 6 minutes, and the rate of change in film thickness (%) before and after immersion was determined. The film thickness change rate was evaluated as an index of chemical resistance according to the following criteria.

AA: the change rate of the film thickness is less than 2 percent

A: the film thickness change rate is more than 2% and less than 5%

B: the film thickness change rate is more than 5% and less than 10%

C: the film thickness change rate is more than 10% and less than 15%

D: the film thickness change rate is more than 15%

In the case of AA, A or B, the chemical resistance can be evaluated as good, and in the case of C or D, the chemical resistance can be evaluated as poor. The film thickness was measured at 25 ℃ using an optical interference film thickness measuring apparatus (Lambda Ace VM-1010).

[ evaluation of storage stability ]

The prepared radiation-sensitive composition was sealed in a light-shielding, airtight container. After 7 days at 25 ℃, the container was opened, and the measurement was performed in accordance with the evaluation of the [ radiation sensitivity ], and the increase rate of the radiation sensitivity (minimum exposure) before and after 7 days of storage was calculated. The case where the value is less than 5% is determined as "AA", the case where the value is 5% or more and less than 10% is determined as "a", the case where the value is 10% or more and less than 20% is determined as "B", the case where the value is 20% or more and less than 30% is determined as "C", and the case where the value is 30% or more is determined as "D". Good storage stability can be evaluated in the case of AA, A or B, and poor storage stability can be evaluated in the case of C or D.

[ evaluation of substrate adhesion (development adhesion) ]

Using a rotator to make the radiation sensitiveThe composition was applied to a silicon substrate which was not subjected to HMDS treatment, and then prebaked on a hot plate at 90 ℃ for 2 minutes to form a coating film having an average film thickness of 3.0. mu.m. Exposing the coating film to a mercury lamp at an exposure of 400J/m at 365nm through a pattern mask having a line-and-space pattern with a width of 1-50 μm²Ultraviolet rays of (1). Subsequently, a developing treatment was performed at 25 ℃ for 60 seconds using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide as a developer, and then, rinsing was performed with ultrapure water for 1 minute. In this case, the case where the minimum width measurement value obtained by measuring the minimum width of the line and space pattern remaining without peeling from the substrate is 2 μm or less is determined as "AA", the case where the minimum width measurement value is greater than 2 μm and not greater than 5 μm is determined as "a", the case where the minimum width measurement value is greater than 5 μm and not greater than 10 μm is determined as "B", the case where the minimum width measurement value is greater than 10 μm and not greater than 30 μm is determined as "C", and the case where the minimum width measurement value is greater than 30 μm is determined as "D". In the case of AA, A or B, the adhesion of the substrate is evaluated as good, and in the case of C or D, the adhesion of the substrate is evaluated as poor.

[ Table 3]

In table 2, as for the solvent (G), in the examples using two organic solvents (example 1, example 2, example 4 to example 14, and example 18 to example 20), the solvent 1 and the solvent 2 were used in a mixture in a mass ratio of 1: 1. In examples using three organic solvents (example 3, example 15 to example 17, and comparative example 1 to comparative example 5), solvent 1, solvent 2, and solvent 3 were mixed at a mass ratio of solvent 1: solvent 2: solvent 3 of 5: 4: 1. In table 3, "-" indicates that the mask was not analyzed in the mask evaluation and thus could not be evaluated.

As shown in table 3: the radiation-sensitive compositions of examples 1 to 20 exhibited good radiation sensitivity, and as practical characteristics, the radiation sensitivity, storage stability, substrate adhesion, PCD margin, PED margin, and chemical resistance were all good. In contrast, comparative examples 1 and 2 were not separated by exposure, and were also inferior in chemical resistance. The radiation-sensitive compositions of comparative examples 3 to 5 were inferior to those of examples in the evaluation of storage stability, substrate adhesiveness, PCD margin, and PED margin.