JP2011191344A - Positive radiation-sensitive resin composition, interlayer insulating film and method for forming the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positive radiation-sensitive resin composition which has good alkali developability, can be cured by low-temperature heating, and also has high radiation sensitivity. <P>SOLUTION: The positive radiation-sensitive resin composition includes a polymer having at least one structural unit selected from polyvinyl ethers in which tertiary carbon has an oxetanyl structure and an acid generator. It is preferable that the polymer further includes a maleic anhydride or maleimide structural unit as a monomer unit. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a positive radiation sensitive resin composition suitably used for forming an interlayer insulating film or the like of a flexible display, an interlayer insulating film formed from the positive radiation sensitive resin composition, and a method for forming the same.

  A flexible display can be easily improved in convenience such as weight reduction and downsizing, and has recently been applied to liquid crystal electronic paper, plastic ICs, and the like. As a substrate for such a flexible display, a plastic substrate such as polycarbonate or polyethylene terephthalate has been studied instead of a glass substrate. However, these plastics have a problem that they slightly expand and contract under a heat load and hinder the function as a display, and there is an urgent need to improve heat resistance. On the other hand, as another measure, in order to reduce the thermal stress applied to the plastic substrate, it has been considered to lower the temperature of the flexible display manufacturing process. One of the processes requiring the highest temperature in manufacturing a flexible display is a step of curing the interlayer insulating film by heating, and a reduction in the heating step is required.

  At present, a positive radiation sensitive resin composition is widely used because a material for forming an interlayer insulating film preferably has a small number of steps for obtaining a required pattern shape and has a high surface hardness. ing. As such a positive type radiation sensitive resin composition, for example, JP-A-2001-354822 contains a copolymer composed of an unsaturated carboxylic acid and / or an anhydride thereof, an epoxy group-containing unsaturated compound, and the like. A positive radiation sensitive resin composition is disclosed, which is configured to obtain a surface hardness as an interlayer insulating film by a cleavage reaction of an epoxy group by a carboxyl group. Generally, in order to increase the surface hardness to a level required for practical use as an interlayer insulating film, a heating process at 200 ° C. or higher is required, but when heating is performed at a high temperature of 200 ° C. or higher. May cause deformation of the substrate. On the other hand, considering the heat resistance of the plastic substrate, the temperature of the heating step is preferably 180 ° C. or lower, but in this case, there is a possibility that a desired surface hardness cannot be obtained.

  On the other hand, Japanese Patent Application Laid-Open No. 2009-4394 discloses a flexible display for a flexible display which is excellent in terms of solvent resistance, specific resistance, semiconductor mobility and the like by curing a low temperature curable polyimide precursor at 180 ° C. or lower. It is disclosed that a gate insulating film can be obtained. However, since the coating liquid containing the polyimide precursor of the above document is a chemical curing system and does not have pattern forming ability by exposure and development, fine pattern formation is impossible. Further, in forming an insulating film using a coating solution containing such a polyimide precursor, it often takes 1 hour or more to heat and cure the coating film.

  In view of the above circumstances, it can be cured at a low temperature so as to be suitably used for the production of an insulating film for a flexible display, and can be easily formed and has an alkali developability (characteristic for accurately forming a desired pattern shape). The development of a positive-type radiation-sensitive resin composition having good radiation sensitivity is strongly demanded. Moreover, in the device manufacturing process of a flexible display, it may be necessary to form a laminate by coating the upper layer of the interlayer insulating film. Therefore, the interlayer insulating film is required to have excellent solvent resistance against the solvent used when forming a laminate by coating. Furthermore, the occurrence of burn-in is low in displays such as liquid crystal panels, and high reliability as a display device is also required at the same time.

JP 2001-354822 A JP 2009-4394 A

  The present invention has been made on the basis of the above-described circumstances, and its purpose is a positive radiation-sensitive resin that has good alkali developability, can be cured by low-temperature heating, and has high radiation sensitivity. It is to provide a composition. Another object of the present invention is to provide a positive-type radiation-sensitive resin composition capable of forming an interlayer insulating film for a display such as a liquid crystal panel having excellent solvent resistance, low seizure and excellent reliability. It is.

（式（１）中、Ｒ^１は水素原子又はメチル基であり、Ｘはメチレン基、炭素数２〜２０のアルキレン基、フェニレン基又はナフチレン基であり、Ｒ^２は水素原子、炭素数１〜２０のアルキル基、ベンジル基、フェニル基又はトリル基である。
式（１´）中、Ｒ^１´は水素原子又はメチル基であり、Ｘ´はメチレン基、炭素数２〜２０のアルキレン基、フェニレン基又はナフチレン基であり、Ｒ^２´は水素原子、炭素数１〜２０のアルキル基、ベンジル基、フェニル基又はトリル基である。） The present invention made to solve the above problems
[A] (a1) a polymer containing at least one structural unit selected from the group consisting of structural units represented by the following formulas (1) and (1 ′), and [B] an acid generator This is a positive-type radiation-sensitive resin composition.

(In the formula (1), ^{R 1} is a hydrogen atom or a methyl group, X is a methylene group, an alkylene group having 2 to 20 carbon atoms, a phenylene group or naphthylene group, ^{R 2} represents a hydrogen atom, 1 to carbon atoms 20 alkyl groups, benzyl groups, phenyl groups or tolyl groups.
Wherein (1'), ^{R 1'is} a hydrogen atom or a methyl group, X'is a methylene group, an alkylene group having 2 to 20 carbon atoms, a phenylene group or a naphthylene group, ^{R 2'is} a hydrogen atom, a carbon It is an alkyl group, a benzyl group, a phenyl group, or a tolyl group of formula 1-20. )

  Since the positive radiation sensitive resin composition contains the [A] component and the [B] component having the specific structural unit, the positive radiation sensitive resin composition has excellent alkali developability and is interlayered by heating at a low temperature. An insulating film can be formed, and an interlayer insulating film for a display such as a liquid crystal panel having excellent solvent resistance, less seizure, and high reliability can be formed.

（式（２）中、Ｙは酸素原子又はＮ−Ｒ^３であり、このＲ^３は水素原子、炭素数１〜２０のアルキル基、炭素数４〜１２の脂環式アルキル基、ベンジル基、フェニル基、トリル基又はナフチル基である。） In the positive radiation sensitive resin composition, the [A] polymer preferably further includes (a2) a structural unit represented by the following formula (2).

(In formula (2), Y is an oxygen atom or N—R ³ , and R ³ is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alicyclic alkyl group having 4 to 12 carbon atoms, a benzyl group, A phenyl group, a tolyl group or a naphthyl group.)

  [A] By including the structural unit represented by the above formula (2) in the polymer, the hardness of the cured film can be improved even when cured at a low temperature. The solvent resistance can be further improved.

（式（３）中、Ｒ^４は水素原子又はメチル基である。） In the positive radiation sensitive resin composition, it is preferable that the [A] polymer further includes (a3) a structural unit represented by the following formula (3).

(In formula (3), R ⁴ is a hydrogen atom or a methyl group.)

  When the positive radiation sensitive resin composition contains the structural unit represented by the above formula (3), the curability and alkali developability of the composition can be improved.

（式（４）中、Ｒ^５は水素原子又はメチル基であり、Ｒ^６は水素原子又は炭素数１〜６のアルキル基であり、ｎは０〜１２の整数である。
式（５）中、Ｒ^７は水素原子又はメチル基であり、ｎは０〜１２の整数である。
式（６）中、Ｒ^８は水素原子又はメチル基であり、Ｒ^９は水素原子、炭素数１〜６のアルキル基、フェニル基又はハロゲンであり、ｎは０〜１２の整数である。
式（６´）中、Ｒ^８´は水素原子又はメチル基であり、Ｒ^９´は水素原子、炭素数１〜６のアルキル基、フェニル基又はハロゲンであり、ｎは０〜１２の整数である。） In the positive radiation sensitive resin composition, the [A] polymer further comprises (a4) structural units represented by the following formulas (4), (5), (6), and (6 ′), respectively. It is preferable to include at least one selected from the group.

(In the formula (4), ^{R 5} is a hydrogen atom or a methyl group, ^{R 6} is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, n is an integer from 0 to 12.
In Formula (5), R ⁷ is a hydrogen atom or a methyl group, and n is an integer of 0 to 12.
In Formula (6), R ⁸ is a hydrogen atom or a methyl group, R ⁹ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a halogen, and n is an integer of 0 to 12.
In formula (6 ′), R ^{8 ′} is a hydrogen atom or a methyl group, R ^{9 ′} is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a halogen, and n is an integer of 0 to 12. is there. )

  When the positive radiation sensitive resin composition has a structural unit containing an oxiranyl group or an oxetanyl group in the molecule, the hardness of the insulating film obtained by low-temperature curing can be further increased.

  The positive radiation sensitive resin composition can be suitably used for forming an interlayer insulating film.

The method for forming an interlayer insulating film of the present invention includes:
(1) The process of forming the coating film of the said positive type radiation sensitive resin composition on a board | substrate,
(2) A step of irradiating at least a part of the coating film formed in step (1),
(3) a step of developing the coating film irradiated with radiation in step (2), and (4) a step of heating the coating film developed in step (3).

  By passing through the above-described steps using the positive radiation-sensitive resin composition, a highly reliable interlayer insulating film can be efficiently formed as an insulating film in a display device with high hardness and excellent solvent resistance. .

  In the present specification, the “structural unit” means one unit included in the polymer structure and may be present repeatedly.

  As described above, the positive-type radiation-sensitive resin composition of the present invention exhibits high radiation sensitivity, forms an interlayer insulating film that has high surface hardness even when heated at a low temperature for a short time, and has excellent alkali developability. It is possible to form an interlayer insulating film excellent in solvent resistance and excellent in reliability as an insulating film of a display device or the like with little burn-in. Therefore, the positive radiation sensitive resin composition can be suitably used as a material for forming an interlayer insulating film of a flexible display.

  The positive radiation sensitive resin composition of the present invention contains a [A] polymer and a [B] acid generator. [A] The polymer contains (a1) structural units represented by the above formulas (1) and (1 ′) (hereinafter also simply referred to as “structural unit (a1)”). The above-mentioned [A] polymer has (a2) a structural unit represented by the above formula (2) (hereinafter also simply referred to as “structural unit (a2)”) and (a3) the above formula ( 3) (hereinafter simply referred to as “structural unit (a3)”), structural units represented by the above formulas (4) to (6) and (6 ′) (hereinafter simply referred to as “structure”). Unit (a4) ") may be included. The positive radiation sensitive resin composition may further contain other optional components. Hereinafter, each component will be described.

<[A] component>
[A] The polymer contains the structural unit (a1) and is a component that becomes a matrix portion when an interlayer insulating film is formed from the positive radiation-sensitive resin composition. This [A] polymer may be a polymer of a constituent monomer alone that generates the structural unit (a1), and the polymer of the structural unit (a1) and one or a plurality of constituent monomers that generate other structural units. It may be a polymer. Hereinafter, the structural unit (a1) and other structural units will be described.

<Structural unit (a1)>
The structural unit (a1) is a structural unit derived from a vinyloxyalkyloxetane compound or a vinyloxyaryloxetane compound.

  Specific examples of the vinyloxyalkyloxetane compound that gives rise to the structural unit (a1) represented by the above formula (1) include, for example, 3-methyl-3- (vinyloxymethyl) oxetane, 3-ethyl-3 -(Vinyloxymethyl) oxetane, 3-propyl-3- (vinyloxymethyl) oxetane, 3-benzyl-3- (vinyloxymethyl) oxetane, 3-phenyl-3- (vinyloxymethyl) oxetane, 3-ethyl -3- (2-vinyloxyethyl) oxetane, 3-ethyl-3- (3-vinyloxypropyl) oxetane, 3-ethyl-3- (4-vinyloxybutyl) oxetane, 3-ethyl-3- (5-vinyloxypentyl) ) Oxetane, 3-ethyl-3- (6-vinyloxyhexyl) oxetane, 3-ethyl-3- (12-vinyloxide) ) Oxetane, 3-ethyl-3-[(α-methylvinyloxy) methyl] oxetane, 3-butyl-3-[(α-methylvinyloxy) methyl] oxetane, 3-phenyl-3- (6-vinyloxy) Hexyl) oxetane and the like.

  Specific examples of the vinyloxyaryl oxetane compound that gives rise to the structural unit (a1) represented by the above formula (1) include, for example, 3-methyl-3- (vinyloxyphenyl) oxetane, 3-ethyl -3- (vinyloxyphenyl) oxetane, 3-propyl-3- (vinyloxyphenyl) oxetane, 3-benzyl-3- (vinyloxyphenyl) oxetane, 3-phenyl-3- (vinyloxyphenyl) oxetane, 3 -Methyl-3- (vinyloxynaphthyl) oxetane, 3-ethyl-3- (vinyloxynaphthyl) oxetane, 3-propyl-3- (vinyloxynaphthyl) oxetane, 3-benzyl-3- (vinyloxynaphthyl) oxetane 3-phenyl-3- (vinyloxynaphthyl) oxetane, 3-ethyl-3-[(α-methylvini Xyl) phenyl] oxetane, 3-butyl-3-[(α-methylvinyloxy) phenyl] oxetane, 3-ethyl-3-[(α-methylvinyloxy) naphthyl] oxetane, 3-butyl-3-[( α-methylvinyloxy) naphthyl] oxetane and the like. The structural unit (a1) may be used alone or in combination of two or more.

  Specific examples of the vinyloxyalkyloxetane compound that gives rise to the structural unit (a1) represented by the above formula (1 ′) include, for example, 2-methyl-2- (vinyloxymethyl) oxetane, 2-ethyl- 2- (vinyloxymethyl) oxetane, 2-propyl-2- (vinyloxymethyl) oxetane, 3-benzyl-3- (vinyloxymethyl) oxetane, 2-phenyl-2- (vinyloxymethyl) oxetane, 2- Ethyl-2- (2-vinyloxyethyl) oxetane, 2-ethyl-2- (3-vinyloxypropyl) oxetane, 2-ethyl-2- (4-vinyloxybutyl) oxetane, 2-ethyl-2- (5-vinyloxy) Pentyl) oxetane, 2-ethyl-2- (6-vinyloxyhexyl) oxetane, 2-ethyl-2- (12-vinyloxide) L) oxetane, 2-ethyl-2-[(α-methylvinyloxy) methyl] oxetane, 2-butyl-2-[(α-methylvinyloxy) methyl] oxetane, 2-phenyl-2- (6-vinyl) Roxyhexyl) oxetane and the like.

  Specific examples of the vinyloxyaryl oxetane compound that generates the structural unit (a1) represented by the above formula (1 ′) include, for example, 2-methyl-2- (vinyloxyphenyl) oxetane, 2- Ethyl-2- (vinyloxyphenyl) oxetane, 2-propyl-2- (vinyloxyphenyl) oxetane, 2-benzyl-2- (vinyloxyphenyl) oxetane, 2-phenyl-2- (vinyloxyphenyl) oxetane, 2-methyl-2- (vinyloxynaphthyl) oxetane, 2-ethyl-2- (vinyloxynaphthyl) oxetane, 2-propyl-2- (vinyloxynaphthyl) oxetane, 2-benzyl-2- (vinyloxynaphthyl) Oxetane, 2-phenyl-2- (vinyloxynaphthyl) oxetane, 2-ethyl-2-[(α-methylvini Loxy) phenyl] oxetane, 2-butyl-2-[(α-methylvinyloxy) phenyl] oxetane, 2-ethyl-2-[(α-methylvinyloxy) naphthyl] oxetane, 2-butyl-2-[( α-methylvinyloxy) naphthyl] oxetane and the like. The structural unit (a1) may be used alone or in combination of two or more.

  Preferred examples of the structural unit (a1) include 3-ethyl-3- (vinyloxymethyl) oxetane, 3-ethyl-3- (6-vinyloxyhexyl) oxetane, 3-phenyl-3- (vinyloxymethyl). ) Oxetane, 3-phenyl-3- (6-vinyloxyhexyl) oxetane, 2-ethyl-2- (vinyloxymethyl) oxetane and the like.

  In the positive radiation sensitive resin composition, the content of the structural unit (a1) may be determined in consideration of the hardness and solvent resistance of the target insulating layer and the like. The content of the structural unit (a1) is preferably 20 parts by mass or more and 80 parts by mass or less, and more preferably 30 parts by mass or more and 60 parts by mass or less with respect to 100 parts by mass of the total amount of the [A] polymer. When content of a structural unit (a1) exists in the said range, hardness and solvent resistance, such as a cured film obtained using the said positive radiation sensitive resin composition, can be improved.

<Structural unit (a2)>
[A] The polymer preferably further contains the structural unit (a2). The structural unit (a2) is a structural unit derived from an unsaturated dicarboxylic anhydride derivative. Specific examples of the unsaturated dicarboxylic acid anhydride derivative include maleic anhydride, maleimide, N-methylmaleimide, N-ethylmaleimide, N-butylmaleimide, N-pentylmaleimide, N-hexylmaleimide, and N-heptylmaleimide. N-octylmaleimide, N-cyclopentylmaleimide, N-cyclohexylmaleimide, N-cycloheptylmaleimide, N-norbornylmaleimide, N-phenylmaleimide, N-benzylmaleimide, N-naphthylmaleimide and the like. The structural unit (a2) can be used alone or in combination of two or more.

  Preferable examples of the structural unit represented by the above formula (2) include maleic anhydride, N-cyclohexylmaleimide, and N-phenylmaleimide.

  The content in the case of including the structural unit (a2) in the positive radiation sensitive resin composition may be determined in consideration of the hardness and solvent resistance of the target insulating layer and the like. The content of the structural unit (a2) is preferably 10 parts by mass or more and 50 parts by mass or less, and more preferably 20 parts by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the total amount of the [A] polymer. When the content of the structural unit (a2) is in the above range, the positive radiation-sensitive resin composition exhibits moderate alkali solubility upon irradiation with radiation, and improves the hardness and solvent resistance of the resulting cured film and the like. Can be made.

  [A] The content ratio of the structural unit (a1) and the structural unit (a2) when the polymer includes the structural unit (a2) is, for example, 100 parts by mass of the structural unit (a1). The structural unit (a2) may be used in an amount of 10 to 150 parts by mass, preferably 20 to 120 parts by mass, more preferably 30 to 110 parts by mass. By adopting values in the above range as the contents of the structural unit (a1) and the structural unit (a2), the hardness and solvent resistance of the obtained interlayer insulating layer and the like can be increased.

  The positive radiation-sensitive resin composition may contain structural units (a3) to (a6) as further structural units in addition to the structural units (a1) and (a2).

<Structural unit (a3)>
The structural unit represented by the above formula (3) is a structural unit derived from acrylic acid or methacrylic acid. When the positive radiation sensitive resin composition contains the structural unit (a3), the alkali developability can be improved and the hardness of the interlayer insulating film obtained by low-temperature curing can be improved.

  The content in the case where the positive radiation sensitive resin composition contains the structural unit (a3) may be determined in consideration of the required alkali development degree and the hardness of the insulating layer. For example, 100 parts by weight of the component [A] Is preferably 0.1 parts by mass or more and 20 parts by mass or less, and more preferably 1 part by mass or more and 10 parts by mass or less.

<Structural unit (a4)>
The structural unit (a4) is a structural unit derived from an epoxy group-containing unsaturated compound having radical polymerizability. Examples of the epoxy group include an oxiranyl group (1,2-epoxy structure) and an oxetanyl group (1,3-epoxy structure).

  Specific examples of the epoxy group-containing unsaturated compound that yields the structural unit (a4) represented by the above formula (4) include, for example, glycidyl acrylate, glycidyl methacrylate, 3,4-epoxybutyl acrylate, and methacrylic acid. -3,4-epoxybutyl, methacrylic acid-3-methyl-3,4-epoxybutyl, methacrylic acid-3-ethyl-3,4-epoxybutyl, acrylic acid-5,6-epoxyhexyl, methacrylic acid-5 , 6-epoxyhexyl, methacrylic acid-5-methyl-5,6-epoxyhexyl, methacrylic acid-5-ethyl-5,6-epoxyhexyl, acrylic acid-6,7-epoxyheptyl, methacrylic acid-6,7 -Epoxy heptyl etc. are mentioned.

  Specific examples of the epoxy group-containing unsaturated compound that yields the structural unit (a4) represented by the above formula (5) include, for example, 3,4-epoxycyclohexyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate, 3,4-epoxycyclohexylethyl methacrylate, 3,4-epoxycyclohexylpropyl methacrylate, 3,4-epoxycyclohexylbutyl methacrylate, 3,4-epoxycyclohexylhexyl methacrylate, 3,4-epoxycyclo Hexyl acrylate, 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexylethyl acrylate, 3,4-epoxycyclohexylpropyl acrylate, 3,4-epoxycyclohexylbutyl acrylate, 3, 4-epoki Carboxymethyl hexyl acrylate cyclohexane and the like.

  Specific examples of the epoxy group-containing unsaturated compound that yields the structural unit (a4) represented by the above formula (6) include, for example, 3- (acryloyloxymethyl) oxetane and 3- (acryloyloxymethyl) -3-methyloxetane. , 3- (acryloyloxymethyl) -3-ethyloxetane, 3- (acryloyloxymethyl) -3-phenyloxetane, 3- (2-acryloyloxyethyl) oxetane, 3- (2-acryloyloxyethyl) -3- Acrylic acid esters such as ethyloxetane, 3- (2-acryloyloxyethyl) -3-ethyloxetane, 3- (2-acryloyloxyethyl) -3-phenyloxetane;

  3- (methacryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl) -3-methyloxetane, 3- (methacryloyloxymethyl) -3-ethyloxetane, 3- (methacryloyloxymethyl) -3-phenyloxetane, 3- (2-methacryloyloxyethyl) oxetane, 3- (2-methacryloyloxyethyl) -3-ethyloxetane, 3- (2-methacryloyloxyethyl) -3-ethyloxetane, 3- (2-methacryloyloxyethyl) -3 -Methacrylic acid esters such as phenyloxetane. The structural unit (a4) can be used alone or in combination of two or more.

  Specific examples of the epoxy group-containing unsaturated compound that yields the structural unit (a4) represented by the above formula (6 ′) include, for example, 2- (acryloyloxymethyl) oxetane, 2- (acryloyloxymethyl) -2- Methyl oxetane, 2- (acryloyloxymethyl) -2-ethyloxetane, 2- (acryloyloxymethyl) -2-phenyloxetane, 2- (2-acryloyloxyethyl) oxetane, 2- (2-acryloyloxyethyl)- Acrylic acid esters such as 2-ethyloxetane, 2- (2-acryloyloxyethyl) -2-ethyloxetane, 2- (2-acryloyloxyethyl) -2-phenyloxetane;

  2- (methacryloyloxymethyl) oxetane, 2- (methacryloyloxymethyl) -2-methyloxetane, 2- (methacryloyloxymethyl) -2-ethyloxetane, 2- (methacryloyloxymethyl) -2-phenyloxetane, 2- (2-methacryloyloxyethyl) oxetane, 2- (2-methacryloyloxyethyl) -2-ethyloxetane, 2- (2-methacryloyloxyethyl) -2-ethyloxetane, 2- (2-methacryloyloxyethyl) -2 -Methacrylic acid esters such as phenyloxetane. The structural unit (a4) can be used alone or in combination of two or more.

  What is necessary is just to change content in the case of including the said structural unit (a4) according to the hardness of the required interlayer insulation layer, for example, 5 mass parts or more and 40 masses with respect to 100 mass parts of said [A] component. Is preferably 10 parts by mass or more and 30 parts by mass or less. By setting the content of the structural unit (a4) in the above range, an interlayer insulating layer having a desired hardness can be formed. In addition, when employ | adopting combining the said structural unit (a4) 2 or more types, those total amounts should just be in the said range.

As other structural units other than the structural units (a1) to (a4), for example,
Methacrylic acid chain alkyl esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, isodecyl methacrylate, n-lauryl methacrylate, tridecyl methacrylate, n-stearyl methacrylate;
Cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yloxyethyl methacrylate , Cyclic alkyl esters of methacrylic acid such as isobornyl methacrylate;
Hydroxyl groups such as hydroxymethyl methacrylate, 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, diethylene glycol monomethacrylate, 2,3-dihydroxypropyl methacrylate, 2-methacryloxyethylglycoside, 4-hydroxyphenyl methacrylate, etc. Methacrylic acid ester having
Cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl acrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yloxyethyl acrylate Cyclic alkyl esters of acrylic acid such as isobornyl acrylate;
Methacrylic acid aryl esters such as phenyl methacrylate and benzyl methacrylate;

Acrylic acid aryl esters such as phenyl acrylate and benzyl acrylate;
Unsaturated dicarboxylic acid diesters such as diethyl maleate, diethyl fumarate, diethyl itaconate;
Unsaturated aromatic compounds such as styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, vinyltoluene, p-methoxystyrene;
Examples thereof include conjugated dienes such as 1,3-butadiene, isoprene, and 2,3-dimethyl-1,3-butadiene.

[A] The weight average molecular weight in terms of polystyrene (hereinafter referred to as “Mw”) by GPC (gel permeation chromatography) of the polymer is preferably 2.0 × 10 ^{3 to} 1.0 × 10 ⁵ , and more. Preferably it is 5.0 * 10 < ³ > -5.0 * 10 < ⁴ >. [A] By making Mw of a polymer into the said range, the radiation sensitivity and alkali developability of a positive radiation sensitive resin composition can be improved.

  Further, the molecular weight distribution “Mw / Mn” of [A] polymer (where “Mn” is the polystyrene-equivalent number average molecular weight of [A] polymer measured by gel permeation chromatography) is preferable. It is 3.0 or less, more preferably 2.6 or less. [A] By setting Mw / Mn of the polymer to 3.0 or less, the developability of the obtained interlayer insulating film can be improved. [A] The positive-type radiation-sensitive resin composition containing a polymer can easily form a desired pattern shape without causing development residue during development.

<[A] Production method of polymer>
[A] Examples of the solvent used in the polymerization reaction for producing the polymer include alcohols, ethers, glycol ethers, ethylene glycol alkyl ether acetates, diethylene glycol alkyl ethers, propylene glycol monoalkyl ethers, and propylene glycol monoalkyls. Examples include ether acetate, propylene glycol monoalkyl ether propionate, aromatic hydrocarbons, ketones, and other esters.

These solvents include
Examples of alcohols include methanol, ethanol, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol and the like;
Ethers such as tetrahydrofuran;
Examples of glycol ethers include ethylene glycol monomethyl ether and ethylene glycol monoethyl ether;
Examples of the ethylene glycol alkyl ether acetate include methyl cellosolve acetate, ethyl cellosolve acetate, and ethylene glycol monobutyl ether acetate;
Examples of the diethylene glycol alkyl ether include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether and the like;
Examples of propylene glycol monoalkyl ethers include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether and the like;

Examples of the propylene glycol monoalkyl ether acetate include propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate;
As propylene glycol monoalkyl ether propionate, for example, propylene monoglycol methyl ether propionate, propylene glycol monoethyl ether propionate, propylene glycol monopropyl ether propionate, propylene glycol monobutyl ether propionate and the like;
Examples of aromatic hydrocarbons include toluene and xylene;
Examples of ketones include methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, and the like;

  Examples of other esters include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, hydroxyacetic acid Methyl, ethyl hydroxyacetate, butyl hydroxyacetate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, propyl 3-hydroxypropionate, butyl 3-hydroxypropionate, Methyl 2-hydroxy-3-methylbutanoate, methyl methoxyacetate, ethyl methoxyacetate, propyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, propyl ethoxyacetate, butyl ethoxyacetate, Methyl poxyacetate, ethyl propoxyacetate, propylpropoxyacetate, butyl propoxyacetate, methyl butoxyacetate, ethyl butoxyacetate, propylbutoxyacetate, butylbutoxyacetate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, 2-methoxypropionate Propyl acid, butyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate, propyl 2-ethoxypropionate, butyl 2-ethoxypropionate, methyl 2-butoxypropionate, 2-butoxypropionic acid Ethyl, propyl 2-butoxypropionate, butyl 2-butoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, 3-metho Butyl cypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, propyl 3-ethoxypropionate, butyl 3-ethoxypropionate, methyl 3-propoxypropionate, ethyl 3-propoxypropionate, 3-propoxy Examples include esters such as propyl propionate, butyl 3-propoxypropionate, methyl 3-butoxypropionate, ethyl 3-butoxypropionate, propyl 3-butoxypropionate, and butyl 3-butoxypropionate.

  Among these solvents, ethylene glycol alkyl ether acetate, diethylene glycol alkyl ether, propylene glycol monoalkyl ether, and propylene glycol alkyl ether acetate are preferable, and in particular, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate. Is preferred.

[A] As the polymerization initiator used in the polymerization reaction for producing the polymer, those generally known as radical polymerization initiators can be used. Examples of the radical polymerization initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobis- (4-methoxy-2). , 4-dimethylvaleronitrile) and other azo compounds;
And organic peroxides such as benzoyl peroxide, lauroyl peroxide, t-butylperoxypivalate, 1,1′-bis- (t-butylperoxy) cyclohexane; and hydrogen peroxide.
When a peroxide is used as the radical polymerization initiator, the peroxide may be used together with a reducing agent to form a redox initiator.

[A] In the polymerization reaction for producing the polymer, a molecular weight modifier can be used to adjust the molecular weight. Specific examples of molecular weight regulators include
Halogenated hydrocarbons such as chloroform and carbon tetrabromide;
mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, thioglycolic acid;
Xanthogens such as dimethylxanthogen sulfide and diisopropylxanthogen disulfide;
Examples include terpinolene and α-methylstyrene dimer.

<[B] Acid generator>
The positive radiation sensitive resin composition of the present invention contains [B] an acid generator together with the above [A] component. The acid generator [B] contained in the positive radiation-sensitive resin composition releases an acidic active substance that acts as a catalyst when accelerating crosslinking and curing of the polymer [A] by applying radiation or heat. It is a possible compound. By using such a [B] acid generator, the hardness and solvent resistance of the resulting interlayer insulating film can be further improved. The radiation is appropriately selected from visible rays, ultraviolet rays, far ultraviolet rays, X-rays, charged particle beams and the like depending on the type of acid generator used. In addition, as [B] acid generator, an acidic active substance is not released at the time of pre-baking at a relatively low temperature (for example, 70 to 120 ° C.) in the coating film forming step of the positive radiation sensitive resin composition, and heating after development. A thermal acid generator having a property of releasing an acidic active substance during post-baking at a relatively high temperature (for example, 120 to 180 ° C.) in the process, or a radiation-sensitive acid generator that generates an acid upon irradiation with radiation during exposure is preferable. . However, the thermal acid generator may generate an acid even when irradiated with radiation, and the radiation-sensitive acid generator may generate an acid by heat. Whether the acid generator is sensitive to heat or radiation can be determined in consideration of the amount of heat and radiation used for acid generation, the loading time, the type of radiation, and the like.

  Examples of the thermal acid generator for the component [B] include diphenyliodonium salts, triphenylsulfonium salts, sulfonium salts, benzothiazonium salts, ammonium salts, phosphonium salts, onium salts such as tetrahydrothiophenium salts, and sulfonimides. Compounds and the like.

  Examples of diphenyliodonium salts include diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphonate, diphenyliodonium hexafluoroarsenate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium trifluoroacetate, diphenyliodonium-p-toluenesulfonate, diphenyl Iodonium butyltris (2,6-difluorophenyl) borate, 4-methoxyphenylphenyliodonium tetrafluoroborate, bis (4-t-butylphenyl) iodonium tetrafluoroborate, bis (4-t-butylphenyl) iodonium hexafluoroarce Bis (4-tert-butylphenyl) iodonium trifluorometa Examples include sulfonate, bis (4-tert-butylphenyl) iodonium trifluoroacetate, bis (4-tert-butylphenyl) iodonium-p-toluenesulfonate, bis (4-tert-butylphenyl) iodonium camphorsulfonic acid, and the like. .

  Examples of triphenylsulfonium salts include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium camphorsulfonic acid, triphenylsulfonium tetrafluoroborate, triphenylsulfonium trifluoroacetate, triphenylsulfonium-p-toluenesulfonate, triphenyl Examples include sulfonium butyl tris (2,6-difluorophenyl) borate.

  Examples of the sulfonium salt include alkylsulfonium salts, benzylsulfonium salts, dibenzylsulfonium salts, substituted benzylsulfonium salts and the like.

As these sulfonium salts,
Examples of the alkylsulfonium salt include 4-acetoxyphenyldimethylsulfonium hexafluoroantimonate, 4-acetoxyphenyldimethylsulfonium hexafluoroarsenate, dimethyl-4- (benzyloxycarbonyloxy) phenylsulfonium hexafluoroantimonate, dimethyl-4- ( Benzoyloxy) phenylsulfonium hexafluoroantimonate, dimethyl-4- (benzoyloxy) phenylsulfonium hexafluoroarsenate, dimethyl-3-chloro-4-acetoxyphenylsulfonium hexafluoroantimonate, etc .;

  Examples of benzylsulfonium salts include benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate, 4-acetoxyphenylbenzylmethylsulfonium hexafluoroantimonate, and benzyl-4-methoxyphenylmethyl. Sulfonium hexafluoroantimonate, benzyl-2-methyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyl-3-chloro-4-hydroxyphenylmethylsulfonium hexafluoroarsenate, 4-methoxybenzyl-4-hydroxyphenylmethyl Sulfonium hexafluorophosphate, etc .;

  Examples of the dibenzylsulfonium salt include dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium hexafluorophosphate, 4-acetoxyphenyl dibenzylsulfonium hexafluoroantimonate, dibenzyl-4-methoxyphenylsulfonium hexa Fluoroantimonate, dibenzyl-3-chloro-4-hydroxyphenylsulfonium hexafluoroarsenate, dibenzyl-3-methyl-4-hydroxy-5-t-butylphenylsulfonium hexafluoroantimonate, benzyl-4-methoxybenzyl-4 -Hydroxyphenylsulfonium hexafluorophosphate and the like;

  Examples of substituted benzylsulfonium salts include p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, p-nitrobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, and p-chlorobenzyl-4-hydroxyphenylmethyl. Sulfonium hexafluorophosphate, p-nitrobenzyl-3-methyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 3,5-dichlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, o-chlorobenzyl-3- And chloro-4-hydroxyphenylmethylsulfonium hexafluoroantimonate.

  Examples of benzothiazonium salts include 3-benzylbenzothiazonium hexafluoroantimonate, 3-benzylbenzothiazonium hexafluorophosphate, 3-benzylbenzothiazonium tetrafluoroborate, 3- (p-methoxy Benzyl) benzothiazonium hexafluoroantimonate, 3-benzyl-2-methylthiobenzothiazonium hexafluoroantimonate, 3-benzyl-5-chlorobenzothiazonium hexafluoroantimonate, and the like.

  Examples of tetrahydrothiophenium salts include 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium Nonafluoro-n-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium-1,1,2,2-tetrafluoro-2- (norbornan-2-yl) ethanesulfonate, 1- (4-n-Butoxynaphthalen-1-yl) tetrahydrothiophenium-2- (5-t-butoxycarbonyloxybicyclo [2.2.1] heptan-2-yl) -1,1,2, 2-tetrafluoroethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydro Ofenium-2- (6-t-butoxycarbonyloxybicyclo [2.2.1] heptan-2-yl) -1,1,2,2-tetrafluoroethanesulfonate, 1- (4,7-dibutoxy-1 -Naphthalenyl) tetrahydrothiophenium trifluoromethanesulfonate and the like.

  Examples of the sulfonimide compound include N- (trifluoromethylsulfonyloxy) succinimide (trade name “SI-105” (manufactured by Midori Chemical Co., Ltd.)), N- (camphorsulfonyloxy) succinimide (trade name “SI-”). 106 "(manufactured by Midori Chemical Co., Ltd.)), N- (4-methylphenylsulfonyloxy) succinimide (trade name" SI-101 "(manufactured by Midori Chemical Co., Ltd.)), N- (2-trifluoromethylphenyl) Sulfonyloxy) succinimide, N- (4-fluorophenylsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (camphorsulfonyloxy) phthalimide, N- (2-trifluoromethylphenylsulfonyloxy) phthalimide N- (2-fluoropheny Sulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) diphenylmaleimide (trade name “PI-105” (manufactured by Midori Chemical Co., Ltd.)), N- (camphorsulfonyloxy) diphenylmaleimide, 4-methylphenylsulfonyloxy ) Diphenylmaleimide, N- (2-trifluoromethylphenylsulfonyloxy) diphenylmaleimide, N- (4-fluorophenylsulfonyloxy) diphenylmaleimide, N- (4-fluorophenylsulfonyloxy) diphenylmaleimide, N- (phenylsulfonyl) Oxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide (trade name “NDI-100” (manufactured by Midori Chemical Co., Ltd.)), N- (4-methylphenylsulfonyloxy) ) Bishik [2.2.1] Hept-5-ene-2,3-dicarboxylimide (trade name “NDI-101” (manufactured by Midori Chemical Co., Ltd.)), N- (trifluoromethanesulfonyloxy) bicyclo [2. 2.1] Hept-5-ene-2,3-dicarboxylimide (trade name “NDI-105” (manufactured by Midori Chemical Co., Ltd.)), N- (nonafluorobutanesulfonyloxy) bicyclo [2.2. 1] Hept-5-ene-2,3-dicarboxylimide (trade name “NDI-109” (manufactured by Midori Chemical Co., Ltd.)), N- (camphorsulfonyloxy) bicyclo [2.2.1] hept- 5-ene-2,3-dicarboxylimide (trade name “NDI-106” (manufactured by Midori Chemical Co., Ltd.)),

  N- (camphorsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (trifluoromethylsulfonyloxy) -7-oxabicyclo [2. 2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-methylphenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-methylphenylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (2-trifluoromethylphenylsulfonyloxy) bicyclo [ 2.2.1] Hept-5-ene-2,3-dicarboximide, N- (2-trifluoromethylphenylsulfonyloxy) -7-oxabi Chlo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-fluorophenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3- Dicarboxylimide, N- (4-fluorophenylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (trifluoromethylsulfonyloxy) bicyclo [2.2.1] Heptane-5,6-oxy-2,3-dicarboxylimide, N- (camphorsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3- Dicarboxylimide, N- (4-methylphenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboxylimide, N- (2 Trifluoromethylphenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboxylimide, N- (4-fluorophenylsulfonyloxy) bicyclo [2.2.1] heptane -5,6-oxy-2,3-dicarboxylimide, N- (trifluoromethylsulfonyloxy) naphthyl dicarboxylimide (trade name “NAI-105” (manufactured by Midori Chemical Co., Ltd.)), N- (camphor Sulfonyloxy) naphthyl dicarboxylimide (trade name “NAI-106” (manufactured by Midori Chemical Co., Ltd.)), N- (4-methylphenylsulfonyloxy) naphthyl dicarboxylimide (trade name “NAI-101” (Midori Chemical) )), N- (phenylsulfonyloxy) naphthyl dicarboxylimide (product) Name “NAI-100” (manufactured by Midori Chemical Co., Ltd.)), N- (2-trifluoromethylphenylsulfonyloxy) naphthyl dicarboxylimide, N- (4-fluorophenylsulfonyloxy) naphthyl dicarboxylimide, N— (Pentafluoroethylsulfonyloxy) naphthyl dicarboxylimide, N- (heptafluoropropylsulfonyloxy) naphthyl dicarboxylimide, N- (nonafluorobutylsulfonyloxy) naphthyl dicarboxylimide (trade name “NAI-109” (Midori Chemical) N- (Ethylsulfonyloxy) naphthyl dicarboxylimide, N- (propylsulfonyloxy) naphthyl dicarboxylimide, N- (butylsulfonyloxy) naphthyl dicarboxylimide (trade name “ AI-1004 "(manufactured by Midori Chemical Co., Ltd.)), N- (pentylsulfonyloxy) naphthyl dicarboxylimide, N- (hexylsulfonyloxy) naphthyl dicarboxylimide, N- (heptylsulfonyloxy) naphthyl dicarboxylimide, N- (octylsulfonyloxy) naphthyl dicarboxylimide, N- (nonylsulfonyloxy) naphthyl dicarboxylimide, etc. are mentioned.

  Among these acid generators, triphenylsulfonium salt, sulfonium salt, benzothiazonium salt, and tetrahydrothiophenium salt are preferably used from the viewpoint of improving the heat resistance and solvent resistance of the obtained interlayer insulating film. . Among these, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium camphorsulfonic acid, 4-acetoxyphenyldimethylsulfonium hexafluoroarsenate, benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 4-acetoxyphenylbenzylmethyl Sulfonium hexafluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, 4-acetoxyphenylbenzylmethylsulfonium hexafluoroantimonate, 3-benzylbenzothiazonium hexafluoroantimonate, benzyl-4-hydroxyphenylmethylsulfonium Hexafluorophosphate, 1- (4,7-dibutoxy 1-naphthalenyl) tetrahydrothiophenium trifluoromethanesulfonate, N- (trifluoromethylsulfonyloxy) naphthyl dicarboxylic imide is preferably used.

  The positive radiation sensitive resin composition preferably contains a quinonediazide compound as the radiation sensitive acid generator of the component [B] together with or in place of the thermal acid generator described above. This quinonediazide compound is a compound that generates a carboxylic acid upon irradiation with radiation. As the quinonediazide compound, a condensate of a phenolic compound or an alcoholic compound (hereinafter referred to as “mother nucleus”) and 1,2-naphthoquinonediazidesulfonic acid halide can be used.

  Examples of the mother nucleus include trihydroxybenzophenone, tetrahydroxybenzophenone, pentahydroxybenzophenone, hexahydroxybenzophenone, (polyhydroxyphenyl) alkane, and other mother nuclei.

As these mother cores,
Examples of trihydroxybenzophenone include 2,3,4-trihydroxybenzophenone and 2,4,6-trihydroxybenzophenone;
Examples of tetrahydroxybenzophenone include 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2,3,4,3′-tetrahydroxybenzophenone, 2,3,4,4′-tetrahydroxybenzophenone, 2,3, 4,2′-tetrahydroxy-4′-methylbenzophenone, 2,3,4,4′-tetrahydroxy-3′-methoxybenzophenone, etc .;
Examples of pentahydroxybenzophenone include 2,3,4,2 ′, 6′-pentahydroxybenzophenone and the like;
Examples of hexahydroxybenzophenone include 2,4,6,3 ′, 4 ′, 5′-hexahydroxybenzophenone, 3,4,5,3 ′, 4 ′, 5′-hexahydroxybenzophenone and the like;

  Examples of (polyhydroxyphenyl) alkanes include bis (2,4-dihydroxyphenyl) methane, bis (p-hydroxyphenyl) methane, tris (p-hydroxyphenyl) methane, 1,1,1-tris (p-hydroxyphenyl). ) Ethane, bis (2,3,4-trihydroxyphenyl) methane, 2,2-bis (2,3,4-trihydroxyphenyl) propane, 1,1,3-tris (2,5-dimethyl-4) -Hydroxyphenyl) -3-phenylpropane, 4,4 '-[1- [4- [1- [4-hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] bisphenol, bis (2,5-dimethyl- 4-hydroxyphenyl) -2-hydroxyphenylmethane, 3,3,3 ′, 3′-tetramethyl-1,1′-spirobiin Down -5,6,7,5 ', 6', 7'-hexanol, 2,2,4-trimethyl -7,2 ', 4'-trihydroxy flavan like;

  As other mother nucleus, for example, 2-methyl-2- (2,4-dihydroxyphenyl) -4- (4-hydroxyphenyl) -7-hydroxychroman, 1- [1- (3- {1- (4- Hydroxyphenyl) -1-methylethyl} -4,6-dihydroxyphenyl) -1-methylethyl] -3- (1- (3- {1- (4-hydroxyphenyl) -1-methylethyl} -4, 6-dihydroxyphenyl) -1-methylethyl) benzene and 4,6-bis {1- (4-hydroxyphenyl) -1-methylethyl} -1,3-dihydroxybenzene.

  Among these mother nuclei, 2,3,4,4′-tetrahydroxybenzophenone, 1,1,1-tri (p-hydroxyphenyl) ethane, 4,4 ′-[1- [4- [1- [ 4-hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] bisphenol is preferred.

  The 1,2-naphthoquinone diazide sulfonic acid halide is preferably 1,2-naphthoquinone diazide sulfonic acid chloride. Specific examples of 1,2-naphthoquinone diazide sulfonic acid chloride include 1,2-naphthoquinone diazide-4-sulfonic acid chloride and 1,2-naphthoquinone diazide-5-sulfonic acid chloride. Among these, it is particularly preferable to use 1,2-naphthoquinonediazide-5-sulfonic acid chloride.

  Preferable examples of the condensate of a phenolic compound or alcoholic compound and 1,2-naphthoquinonediazide sulfonic acid halide include 1,1,1-tri (p-hydroxyphenyl) ethane and 1,2-naphthoquinonediazide-5. -Condensate with sulfonic acid chloride, 4,4 '-[1- [4- [1- [4-hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] bisphenol and 1,2-naphthoquinonediazide-5 A condensate with sulfonic acid chloride is mentioned.

  In the condensation reaction of the phenolic compound or alcoholic compound (mother nucleus) and 1,2-naphthoquinonediazidesulfonic acid halide, preferably 30 to 85 moles relative to the number of OH groups in the phenolic compound or alcoholic compound. %, More preferably 1,2-naphthoquinonediazidesulfonic acid halide corresponding to 50 to 70 mol% can be used. The condensation reaction can be carried out by a known method.

  Examples of the quinonediazide compound include 1,2-naphthoquinonediazidesulfonic acid amides in which the ester bond of the mother nucleus exemplified above is changed to an amide bond, such as 2,3,4-triaminobenzophenone-1,2-naphthoquinonediazide- 4-sulfonic acid amide and the like are also preferably used. These [B] components can be used individually or in combination of 2 or more types.

  The amount of the thermal acid generator used as the component [B] is preferably 0.1 parts by mass or more and 20 parts by mass or less, more preferably 1 part by mass or more and 10 parts by mass with respect to 100 parts by mass of the polymer [A]. It is below mass parts. By making the usage-amount of a [B] component into the said range, the hardness and solvent resistance of the interlayer insulation film formed using positive type radiation sensitive resin composition can be improved, and the formation process of a coating film The generation of precipitates can be prevented, and coating film formation can be facilitated.

  The amount of the radiation-sensitive acid generator used as the component [B] is preferably 5 to 100 parts by mass, more preferably 10 to 50 parts by mass with respect to 100 parts by mass of the [A] polymer. is there. When the use ratio of the component [B] is in the above range, the difference in solubility between the irradiated portion and the unirradiated portion in the alkaline aqueous solution serving as the developer is large, the patterning performance is improved, and the obtained interlayer insulating film The solvent resistance is also good.

<Other optional components>
The positive radiation-sensitive resin composition of the present invention preferably contains the above-mentioned [A] component as an essential component, and further contains a [B] component in addition to [A]. A crosslinking aid which is a ring-containing compound, [D] a polymerizable compound having at least one ethylenically unsaturated double bond, [E] an epoxy resin other than the [A] polymer, [F] a surfactant, [ G] An adhesion assistant can be contained.

<[C] component>
[C] The crosslinking auxiliary agent of the component is an imidazole ring-containing compound represented by the following formula (7).

（式（７）中、Ｚ^１、Ｚ^２、Ｚ^３及びＲ^１０は、各々独立に、水素原子又は置換基を有していてもよい炭素数１〜２０の直鎖状、分岐状又は環状の炭化水素基を示し、Ｚ^２とＺ^３は互いに連結して環を形成してもよい。）

(In Formula (7), Z < ¹ >, Z < ² >, Z < ³ > and R < ¹⁰ > are respectively independently a C1-C20 linear, branched or cyclic which may have a hydrogen atom or a substituent. And Z ² and Z ³ may be linked to each other to form a ring.)

As a specific example of the hydrocarbon group in the formula (7),
Methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group N-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group An alkyl group having 1 to 20 carbon atoms such as n-octadecyl group, n-nonadecyl group, n-eicosyl group;
A cycloalkyl group having 3 to 20 carbon atoms such as a cyclopentyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group;
Aryl groups having 6 to 20 carbon atoms such as phenyl group, toluyl group, benzyl group, methylbenzyl group, xylyl group, mesityl group, naphthyl group, anthryl group;
Examples thereof include a bridged alicyclic hydrocarbon group having 6 to 20 carbon atoms such as a norbornyl group, a tricyclodecanyl group, a tetracyclododecyl group, an adamantyl group, a methyladamantyl group, an ethyladamantyl group, and a butyladamantyl group.

The hydrocarbon group may be substituted. Specific examples of the substituent include
A hydroxyl group;
Carboxyl group;
Hydroxymethyl group, 1-hydroxyethyl group, 2-hydroxyethyl group, 1-hydroxypropyl group, 2-hydroxypropyl group, 3-hydroxypropyl group, 1-hydroxybutyl group, 2-hydroxybutyl group, 3-hydroxybutyl A hydroxyalkyl group having 1 to 4 carbon atoms such as a 4-hydroxybutyl group;
An alkoxy group having 1 to 4 carbon atoms such as methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, 2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group;
A cyano group;
A cyanoalkyl group having 2 to 5 carbon atoms such as a cyanomethyl group, a 2-cyanoethyl group, a 3-cyanopropyl group, a 4-cyanobutyl group;
An alkoxycarbonyl group having 2 to 5 carbon atoms such as a methoxycarbonyl group, an ethoxycarbonyl group, or a t-butoxycarbonyl group;
An alkoxycarbonylalkoxy group having 3 to 6 carbon atoms such as a methoxycarbonylmethoxy group, an ethoxycarbonylmethoxy group, or a t-butoxycarbonylmethoxy group;
Halogen atoms such as fluorine and chlorine;
Examples thereof include fluoroalkyl groups such as a fluoromethyl group, a trifluoromethyl group, and a pentafluoroethyl group.

In the above formula (7), Z ² and Z ³ may be connected to each other to form a cyclic structure, preferably an aromatic ring, or a saturated or unsaturated ring structure having 2 to 20 carbon atoms. As the nitrogen-containing heterocyclic ring represented by the formulas (7) and (8), for example, a benzimidazole ring may be formed as in the case where the structure of the following formula (8) is adopted.

（式（８）中、Ｗは、互いに独立して、置換基を有していてもよい炭素数１〜２０の直鎖状、分岐状又は環状の炭化水素基を示す。式中の点線は、上記式（７）におけるイミダゾリル環中の、Ｚ^２とＺ^３が結合している炭素原子間の二重結合を示すものである。）

(In Formula (8), W represents a C1-C20 linear, branched or cyclic hydrocarbon group which may have a substituent independently of each other. The dotted line in the formula is And represents a double bond between carbon atoms to which Z ² and Z ³ are bonded in the imidazolyl ring in the above formula (7).)

In addition, as a hydrocarbon group of W of Formula (8), the thing similar to the hydrocarbon group in the said Formula (7) can be mentioned. By using a compound in which Z ² and Z ³ are connected to each other to form a benzimidazole ring, a positive radiation sensitive resin composition having high curability can be obtained.

  Particularly preferred compounds of the component [C] include 2-phenylbenzimidazole, 2-methylimidazole, and 2-methylbenzimidazole. The imidazole ring-containing compound of component [C] can be used alone or in admixture of two or more. A typical use amount of the imidazole ring-containing compound of the [C] component which is an optional component is 0.01 to 10 parts by mass with respect to 100 parts by mass of the alkali-soluble resin of the [A] component. By making the usage-amount of the [C] component in a positive type radiation sensitive resin composition 0.01-10 mass parts, the interlayer insulation film which has still higher surface hardness can be obtained.

<[D] component>
As the polymerizable compound having at least one ethylenically unsaturated double bond as the component [D], for example, monofunctional (meth) acrylate, bifunctional (meth) acrylate, trifunctional or higher (meth) acrylate is preferably used. Can be used.

  Examples of the monofunctional (meth) acrylate include 2-hydroxyethyl (meth) acrylate, carbitol (meth) acrylate, isobornyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, and 2- (meth) acryloyloxyethyl- Examples include 2-hydroxypropyl phthalate. Examples of commercial products of these monofunctional (meth) acrylates include Aronix M-101, M-111, M-114 (above, manufactured by Toagosei Co., Ltd.), KAYARAD TC-110S, TC-120S. (Nippon Kayaku Co., Ltd.), Biscote 158, 2311 (Osaka Organic Chemical Co., Ltd.) and the like.

  Examples of the bifunctional (meth) acrylate include ethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, polypropylene glycol di (meth) acrylate, Examples include tetraethylene glycol di (meth) acrylate, bisphenoxyethanol full orange acrylate, and bisphenoxyethanol full orange acrylate. As a commercial item of these bifunctional (meth) acrylates, for example, Aronix M-210, M-240, M-6200 (manufactured by Toagosei Co., Ltd.), KAYARAD HDDA, HX-220, R -604 (manufactured by Nippon Kayaku Co., Ltd.), Viscoat 260, 312, and 335HP (manufactured by Osaka Organic Chemical Industries, Ltd.).

  Examples of the tri- or higher functional (meth) acrylate include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tri ((meth) acryloyloxyethyl) phosphate, pentaerythritol tetra (meth) acrylate, Examples thereof include dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate. Commercially available products of these tri- or higher functional (meth) acrylates include, for example, Aronix M-309, M-400, M-405, M-450, M-7100, M-8030, and M- 8060 (above, manufactured by Toagosei Co., Ltd.), KAYARAD TMPTA, DPHA, DPCA-20, DPCA-30, DPCA-60, DPCA-60, DPCA-120 (above, Nippon Kayaku Co., Ltd.), Biscoat 295, 300, 360, GPT, 3PA, 400 (above, manufactured by Osaka Organic Chemical Industry Co., Ltd.).

  Of these meth (acrylates), trifunctional or higher functional (meth) acrylates are preferably used from the viewpoint of improving curability of the positive radiation sensitive resin composition. Among these, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and dipentaerythritol hexa (meth) acrylate are particularly preferable. These monofunctional, bifunctional, or trifunctional or higher (meth) acrylates are used alone or in combination.

  The proportion of the [D] component used in the positive radiation sensitive resin composition is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, relative to 100 parts by mass of the [A] polymer. By including the component [D] at such a ratio, the curability of the positive radiation-sensitive resin composition can be improved, and the occurrence of film roughness in the coating film forming step on the substrate is suppressed. It becomes possible.

<[E] component>
The epoxy resin other than the [A] polymer as the [E] component is not particularly limited as long as it does not adversely affect the compatibility with each component contained in the positive radiation sensitive resin composition. Examples of such epoxy resins are preferably bisphenol A type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, cycloaliphatic epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, heterocyclic rings. Examples thereof include a resin obtained by (co) polymerizing a formula epoxy resin and glycidyl methacrylate. Of these, bisphenol A type epoxy resins, cresol novolac type epoxy resins, glycidyl ester type epoxy resins and the like are particularly preferable.

  The use ratio of the [E] component in the positive radiation sensitive resin composition is preferably 30 parts by mass or less with respect to 100 parts by mass of the [A] polymer. By using the [E] component at such a ratio, the curability of the positive radiation sensitive resin composition can be further improved. The [A] polymer can also be referred to as an “epoxy resin”, but is different from the [E] component in that it is not an acrylic polymer.

<[F] component>
In the positive radiation sensitive resin composition, a surfactant can be used as the [F] component in order to further improve the coating property at the time of coating film formation. Examples of the surfactant that can be suitably used include a fluorine-based surfactant, a silicone-based surfactant, and a nonionic surfactant.

  Examples of the fluorosurfactant include, for example, 1,1,2,2-tetrafluorooctyl (1,1,2,2-tetrafluoropropyl) ether, 1,1,2,2-tetrafluorooctylhexyl. Ether, octaethylene glycol di (1,1,2,2-tetrafluorobutyl) ether, hexaethylene glycol (1,1,2,2,3,3-hexafluoropentyl) ether, octapropylene glycol di (1, Fluoroethers such as 1,2,2-tetrafluorobutyl) ether and hexapropylene glycol di (1,1,2,2,3,3-hexafluoropentyl) ether; sodium perfluorododecyl sulfonate; 1,1 , 2, 2, 8, 8, 9, 9, 10, 10-decafluorododecane, 1, 1, 2, 2, 3, 3- Fluoroalkanes such as oxafluorodecane; sodium fluoroalkylbenzenesulfonates; fluoroalkyloxyethylene ethers; fluoroalkylammonium iodides; fluoroalkylpolyoxyethylene ethers; perfluoroalkylpolyoxyethanols; perfluoroalkylalkoxy Rates: Fluorine alkyl esters and the like can be mentioned.

  Commercially available products of these fluorosurfactants include BM-1000, BM-1100 (manufactured by BM Chemie), MegaFack F142D, F172, F173, F183, F178, F191, F191, and F471. (Above, Dainippon Ink & Chemicals, Inc.), Florard FC-170C, FC-171, FC-430, FC-431 (above, Sumitomo 3M Limited), Surflon S-112, S-113 S-131, S-141, S-145, S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (Manufactured by Asahi Glass Co., Ltd.), F-top EF301, 303, 352 (manufactured by Shin-Akita Kasei Co., Ltd.) and the like.

  Specific examples of the silicone-based surfactant are commercially available product names such as DC3PA, DC7PA, FS-1265, SF-8428, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, SH-193, SH 8400 FLUID, SZ-6032 (above, manufactured by Toray Dow Corning Silicone Co., Ltd.), TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, TSF-4442 (above, GE Toshiba) Silicone Co., Ltd.).

  Nonionic surfactants include, for example, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, and the like. Polyoxyethylene aryl ethers; polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate; (meth) acrylic acid copolymers and the like. As a typical commercially available nonionic surfactant, Polyflow No. 57, 95 (manufactured by Kyoeisha Chemical Co., Ltd.). These surfactants can be used alone or in combination of two or more.

  In the positive radiation sensitive resin composition, the surfactant of the component [F] is preferably used in an amount of 5 parts by mass or less, more preferably 2 parts by mass or less, relative to 100 parts by mass of the polymer [A]. It is done. [F] By making the usage-amount of surfactant into 5 mass parts or less, the film dripping at the time of forming a coating film on a board | substrate can be suppressed.

<[G] component>
In the positive radiation sensitive resin composition of the present invention, an adhesion assistant as the [G] component can be used to improve the adhesion to the substrate. As such an adhesion assistant, a functional silane coupling agent is preferably used. Examples of functional silane coupling agents include silane coupling agents having reactive substituents such as carboxyl groups, methacryloyl groups, isocyanate groups, and epoxy groups (preferably oxiranyl groups). Specific examples of functional silane coupling agents include trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxy Examples thereof include propyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. In the positive radiation sensitive resin composition, such an adhesion assistant is preferably 1 part by mass or more and 20 parts by mass or less, more preferably 3 parts by mass or more and 15 parts by mass with respect to 100 parts by mass of the polymer [A]. Used in an amount of less than parts. By adjusting the amount of the adhesion aid to 1 part by mass or more and 20 parts by mass or less, the adhesion between the formed interlayer insulating film and the substrate is improved.

<Positive radiation sensitive resin composition>
The positive radiation-sensitive resin composition of the present invention is prepared by uniformly mixing the above-mentioned [A] component, the [B] component as a suitable component, and optional components ([C] to [G] component). The Usually, the positive radiation-sensitive resin composition is preferably used after being dissolved in an appropriate solvent and stored in a solution state. For example, a positive radiation sensitive resin composition in a solution state can be prepared by mixing [A], the [B] component as a suitable component, and an optional component in a solvent in a predetermined ratio.

  As the solvent used for the preparation of the positive radiation sensitive resin composition, the above [A] component, the [B] component as a suitable component, and the optional components ([C] to [G] component) are included. There is no particular limitation as long as it is uniformly dissolved and does not react with each component. Examples of such a solvent include the same solvents as those exemplified as the solvent that can be used for producing the [A] polymer.

  Among such solvents, alcohols, glycol ethers, ethylene glycol alkyl ether acetates, esters, and diethylene glycol alkyl ethers from the standpoints of solubility of each component, non-reactivity with each component, ease of film formation, etc. Is preferably used. Among these solvents, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether , Propylene glycol monomethyl ether acetate, methyl 2- or 3-methoxypropionate, or ethyl 2- or 3-ethoxypropionate can be particularly preferably used.

  Furthermore, in order to improve the in-plane uniformity of the film thickness of the coating film to be formed, a high boiling point solvent can be used in combination with the above solvent. Examples of the high-boiling solvent that can be used in combination include N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, and benzylethyl. Ether, dihexyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, Examples include phenyl cellosolve acetate. Of the high boiling point solvents, N-methylpyrrolidone, γ-butyrolactone, and N, N-dimethylacetamide are preferable.

  When a high boiling point solvent is used in combination as a solvent for the positive radiation sensitive resin composition, the amount used is 50% by mass or less, preferably 40% by mass or less, more preferably 30% by mass or less, based on the total amount of the solvent. be able to. By setting the use ratio of the high boiling point solvent to 50% by mass or less, it is possible to improve the film thickness uniformity of the coating film and at the same time suppress the decrease in radiation sensitivity.

  When preparing the positive radiation-sensitive resin composition in a solution state, components other than the solvent in the solution (that is, the total amount of the [A] polymer and the [B] component as a suitable component, and other optional components) ) Can be arbitrarily set according to the purpose of use, desired film thickness, etc., but is preferably 5 to 50% by mass, more preferably 10 to 40% by mass, and even more preferably 15 to 35% by mass. It is. The solution of the positive radiation sensitive resin composition thus prepared can be used after being filtered using a Millipore filter having a pore size of about 0.2 μm.

<Formation of interlayer insulating film>
Next, a method for forming the interlayer insulating film of the present invention using the positive radiation sensitive resin composition described above will be described. The method includes the following steps in the order described below.
(1) forming a coating film of the positive radiation sensitive resin composition of the present invention on a substrate;
(2) A step of irradiating at least a part of the coating film formed in step (1),
(3) a step of developing the coating film irradiated with radiation in step (2), and (4) a step of heating the coating film developed in step (3).

[(1) Step of forming coating film of positive radiation sensitive resin composition on substrate]
In the step (1), the positive radiation-sensitive resin composition of the present invention is applied to the substrate surface, and preferably the pre-baking is performed to remove the solvent. The coating film is formed. The types of substrates that can be used include, for example, glass substrates, silicon wafers, polyethylene terephthalate (PET), polybutylene terephthalate, polyethersulfone, polycarbonate, resin substrates made of plastics such as polyimide, and various metals formed on the surfaces thereof. Can be mentioned.

  The method for applying the solution of the composition is not particularly limited. For example, an appropriate method such as a spray method, a roll coating method, a spin coating method (spin coating method), a slit die coating method, a bar coating method, or an ink jet method may be used. Can be adopted. Among these coating methods, spin coating, slit die coating, and bar coating are preferable. The pre-baking conditions vary depending on the type of each component, the use ratio, and the like, but can be, for example, 60 to 90 ° C. for 30 seconds to 10 minutes. The film thickness of the coating film to be formed is preferably 0.1 to 8 μm, more preferably 0.1 to 6 μm, and further preferably 0.1 to 4 μm as a value after pre-baking.

[(2) Step of irradiating at least part of coating film with radiation]
In the step (2), the formed coating film is irradiated with radiation through a mask having a predetermined pattern. As the radiation used in this step, the radiation used for the radiation-sensitive acid generator is suitable. Among these, examples of ultraviolet rays include g-line (wavelength 436 nm), i-line (wavelength 365 nm), and the like. Examples of the far ultraviolet light include a KrF excimer laser. Examples of X-rays include synchrotron radiation. Examples of the charged particle beam include an electron beam. Among these radiations, ultraviolet rays are preferable, and among the ultraviolet rays, radiation containing g-line and / or i-line is particularly preferable. The exposure amount is preferably 30 to 1,500 J / m ² .

[(3) Development process]
(3) In the development step, the coating film irradiated with the radiation in the step (2) can be developed to remove the radiation irradiated portion, thereby forming a desired pattern. Examples of the developer used for the development processing include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, diethylaminoethanol, di-n-propylamine. , Triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5,4,0] -7-undecene, 1,5- An aqueous solution of an alkali (basic compound) such as diazabicyclo [4,3,0] -5-nonane can be used. In addition, an aqueous solution in which an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant is added to the above alkaline aqueous solution, or an alkaline aqueous solution containing a small amount of various organic solvents that dissolve the positive-type radiation-sensitive resin composition is developed. It can be used as a liquid.

  As a developing method, for example, an appropriate method such as a liquid piling method, a dipping method, a rocking dipping method, a shower method or the like can be used. The development time varies depending on the composition of the positive radiation-sensitive resin composition, but can be, for example, 30 to 120 seconds.

  After the development step, the patterned thin film is rinsed with running water, followed by irradiation with the above-described radiation by a high-pressure mercury lamp or the like (post-exposure), so that the quinonediazide compound remaining in the thin film It is preferable to perform a decomposition process.

[(4) Heating process]
Next, (4) in the heating step, the thin film is cured by heating and curing (post-baking) the thin film using a heating device such as a hot plate or an oven. The exposure amount in the post-exposure is preferably about 2,000 to 5,000 J / m ² . Moreover, the temperature in this heating process becomes like this. Preferably it is 120-180 degreeC, Most preferably, it is 120-150 degreeC. The heating time varies depending on the type of heating equipment, but for example, it can be 5 to 40 minutes when heat treatment is performed on a hot plate, and 30 to 80 minutes when heat treatment is performed in an oven, Particularly preferably, it is within 30 minutes when heat treatment is performed on a hot plate, and within 60 minutes when heat treatment is performed in an oven. In this way, a patterned thin film corresponding to the target interlayer insulating film can be formed on the surface of the substrate.

<Interlayer insulation film>
As described above, the interlayer insulating film of the present invention formed by heating at a low temperature for a short time has sufficient surface hardness, solvent resistance and voltage holding, as will be apparent from the examples described later. The rate is excellent. Therefore, this interlayer insulating film is suitably used as an interlayer insulating film for flexible displays.

  EXAMPLES Hereinafter, although a synthesis example and an Example demonstrate this invention further in detail, this invention is not limited to these Examples.

Hereinafter, the mass average molecular weight (Mw) and the number average molecular weight (Mn) of the copolymer were measured by gel permeation chromatography (GPC) under the following conditions.
Apparatus: GPC-101 (made by Showa Denko KK)
Column: GPC-KF-801, GPC-KF-802, GPC-KF-803 and GPC-KF-804 are combined Mobile phase: Tetrahydrofuran Column temperature: 40 ° C
Flow rate: 1.0 mL / min Sample concentration: 1.0% by mass
Sample injection amount: 100 μm
Detector: Differential refractometer Standard material: Monodispersed polystyrene The solution viscosity of the positive radiation sensitive resin composition was measured at 30 ° C. using an E type viscometer (manufactured by Tokyo Keiki Co., Ltd.).

<Polymer synthesis example>
[Synthesis Example 1]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 60 parts by weight of 3-ethyl-3- (vinyloxymethyl) oxetane, 20 parts by weight of maleic anhydride, and 20 parts by weight of styrene were charged, and after the atmosphere was replaced with nitrogen, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 hours to obtain a polymer solution containing the polymer [A-1]. This polymer [A-1] had a polystyrene-reduced mass average molecular weight (Mw) of 6,000 and a molecular weight distribution (Mw / Mn) of 2.5. Further, the solid content concentration of the polymer solution obtained here (the ratio of the mass of the polymer contained in the polymer solution to the total weight of the polymer solution; the same shall apply hereinafter) is 33.4% by mass. there were.

[Synthesis Example 2]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 40 parts by weight of 3-ethyl-3- (vinyloxymethyl) oxetane, 30 parts by weight of cyclohexylmaleimide, 16 parts by weight of methacrylic acid and 14 parts by weight of styrene were charged, and after the atmosphere was replaced with nitrogen, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 hours to obtain a polymer solution containing the polymer [A-2]. The polymer [A-2] had a polystyrene-reduced mass average molecular weight (Mw) of 7,000 and a molecular weight distribution (Mw / Mn) of 2.2. Moreover, the solid content concentration of the polymer solution obtained here was 34.1% by mass.

[Synthesis Example 3]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 30 parts by weight of 3-ethyl-3- (vinyloxymethyl) oxetane, 30 parts by weight of cyclohexylmaleimide, 16 parts by weight of methacrylic acid, and 24 parts by weight of glycidyl methacrylate were charged, and the mixture was gently stirred. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 hours to obtain a polymer solution containing the polymer [A-3]. This polymer [A-3] had a polystyrene equivalent weight average molecular weight (Mw) of 8,000 and a molecular weight distribution (Mw / Mn) of 2.3. The solid content concentration of the obtained polymer solution was 34.4% by mass.

[Synthesis Example 4]
A flask equipped with a condenser and a stirrer was charged with 8 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 30 parts by weight of 3-ethyl-3- (vinyloxymethyl) oxetane, 30 parts by weight of phenylmaleimide, 16 parts by weight of methacrylic acid, and 24 parts by weight of glycidyl methacrylate were charged, and the mixture was gently stirred. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 5 hours to obtain a polymer solution containing the polymer [A-4]. This polymer [A-4] had a polystyrene-reduced mass average molecular weight (Mw) of 8,000 and a molecular weight distribution (Mw / Mn) of 2.3. Moreover, the solid content concentration of the polymer solution obtained here was 31.9 mass%.

[Synthesis Example 5]
A flask equipped with a condenser and a stirrer was charged with 8 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 30 parts by weight of 3-ethyl-3- (vinyloxymethyl) oxetane, 30 parts by weight of maleic anhydride, 16 parts by weight of methacrylic acid, 24 parts by weight of glycidyl methacrylate were charged, and after gently substituting with nitrogen, stirring was started gently. . The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 5 hours to obtain a polymer solution containing the polymer [A-5]. The polymer [A-5] had a polystyrene-reduced mass average molecular weight (Mw) of 7,800 and a molecular weight distribution (Mw / Mn) of 2.2. Moreover, the solid content concentration of the polymer solution obtained here was 33.9 mass%.

[Synthesis Example 6]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 30 parts by weight of 3-ethyl-3- (6-vinyloxyhexyl) oxetane, 30 parts by weight of cyclohexylmaleimide, 16 parts by weight of methacrylic acid, and 24 parts by weight of 3- (methacryloyloxymethyl) -3-ethyloxetane were charged, and nitrogen was added. After the replacement, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 hours to obtain a polymer solution containing the polymer [A-6]. The polymer [A-6] had a polystyrene-reduced mass average molecular weight (Mw) of 7,000 and a molecular weight distribution (Mw / Mn) of 2.4. Moreover, the solid content concentration of the polymer solution obtained here was 34.5 mass%.

[Synthesis Example 7]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 30 parts by weight of 3-phenyl-3- (6-vinyloxyhexyl) oxetane, 30 parts by weight of cyclohexylmaleimide, 16 parts by weight of methacrylic acid, and 24 parts by weight of methacrylic acid (3,4-epoxycyclohexylmethyl) were charged and replaced with nitrogen. After that, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 hours to obtain a polymer solution containing the polymer [A-7]. The polymer [A-7] had a weight average molecular weight (Mw) in terms of polystyrene of 9,000 and a molecular weight distribution (Mw / Mn) of 2.1. Moreover, the solid content concentration of the polymer solution obtained here was 34.8 mass%.

[Synthesis Example 8]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 90 parts by weight of 3-ethyl-3- (vinyloxymethyl) oxetane and 10 parts by weight of styrene were charged, and after nitrogen substitution, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 hours to obtain a polymer solution containing the polymer [A-8]. This polymer [A-8] had a polystyrene-reduced mass average molecular weight (Mw) of 4,000 and a molecular weight distribution (Mw / Mn) of 2.5. Moreover, the solid content concentration of the polymer solution obtained here was 32.5 mass%.

[Comparative Synthesis Example 1]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 16 parts by weight of methacrylic acid, 16 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 58 parts by weight of methyl methacrylate, and 10 parts by weight of styrene were charged, and after nitrogen substitution, Stirring started. By raising the temperature of the solution to 70 ° C. and maintaining this temperature for 4 hours, a polymer solution containing the polymer [a-1] was obtained. This copolymer [a-1] had a polystyrene-reduced mass average molecular weight (Mw) of 7,900 and a molecular weight distribution (Mw / Mn) of 2.3. Moreover, the solid content concentration of the polymer solution obtained here was 33.4 mass%.

[Comparative Synthesis Example 2]
Into a flask equipped with a condenser and a stirrer, 18 parts by mass of 2,2-bis (3-amino-4-methylphenyl) hexafluoropropane was charged under a nitrogen stream, and 75 parts by mass of N-methyl-2-pyrrolidone was added. After dissolution, 9.5 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic anhydride was added, and this was stirred at room temperature for 8 hours to carry out a polymerization reaction. The obtained polyamic acid solution was diluted to 10% by mass with N-methyl-2-pyrrolidone. To this solution, 26 parts by mass of acetic anhydride and 16 parts by mass of pyridine were added as an imidization catalyst, reacted at room temperature for 30 minutes, and then reacted at 40 ° C. for 90 minutes to obtain a polyimide solution. This solution was poured into a mixed solution of a large amount of methanol and water, and the resulting white precipitate was collected by filtration and dried to obtain a white polyimide [a-2-1] powder. This polyimide powder was dissolved in propylene glycol monomethyl ether to obtain a solution containing polyimide [a-2].

<Preparation of positive radiation sensitive resin composition>
[Example 1]
10 mass of phenol novolac type epoxy resin (trade name Epicoat 152: manufactured by Japan Epoxy Resin Co., Ltd.) as the [E] component together with the copolymer and the [B] component obtained in the above synthesis example described in Table 1 below. Part, silicone surfactant (“SH 8400 FLUID” manufactured by Toray Dow Corning Co., Ltd.) 0.1 part by mass as [F] component, and γ-glycidoxypropyltrimethoxysilane 5 as [G] component Mass parts were mixed and dissolved in propylene glycol monomethyl ether acetate so that the solid content concentration was 30% by weight, and then filtered through a Millipore filter having a pore size of 0.5 μm to prepare a composition solution.

[Examples 2-12 and Comparative Examples 1-2]
A positive radiation sensitive resin composition solution was prepared in the same manner as in Example 1 except that the types and amounts shown in Table 1 were used as the component [A] and component [B]. The [F] component and the [G] component were also added in each Example and Comparative Example as in Example 1. The component [E] was used only in Example 1.

The compounds used in Synthesis Examples 1 to 5 and 8 are as follows (in the formula (1), the structural unit (a1) in which X is a methylene group, R ¹ is a hydrogen atom, and R ² is an ethyl group) Corresponding to).
3-ethyl-3- (vinyloxymethyl) oxetane

The compound used in Synthesis Example 6 is represented by the following formula (in the formula (1), corresponding to the structural unit (a1) in which X is a hexamethylene group, R ¹ is a hydrogen atom, and R ² is an ethyl group. ).
3-ethyl-3- (6-vinyloxyhexyl) oxetane

The compound used in Synthesis Example 7 is as follows (corresponding to the structural unit (a1) in which X is a methylene group, R ¹ is a hydrogen atom, and R ² is a phenyl group in the formula (1)). .
3-Phenyl-3- (vinyloxymethyl) oxetane

In Table 1, the symbol of a component shows the following compound.
B-1: Benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate B-2: Diphenyl (4- (phenylthio) phenyl) sulfonium hexafluorophosphate B-3: 4,4 ′-[1- [4- [1- Condensation product of [4-hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] bisphenol (1.0 mol) and 1,2-naphthoquinonediazide-5-sulfonic acid chloride (2.0 mol) B-4: Condensate of 1,1,1-tri (p-hydroxyphenyl) ethane (1.0 mol) and 1,2-naphthoquinonediazide-5-sulfonic acid chloride (3.0 mol)

<Characteristic evaluation as interlayer insulation film>
Using the positive radiation sensitive resin composition prepared as described above, various characteristics as an interlayer insulating film were evaluated as follows.

[Evaluation of radiation sensitivity]
Except for Example 11, the above composition was applied onto a silicon substrate using a spinner, and then pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. The obtained coating film was irradiated with a predetermined amount of ultraviolet rays by a mercury lamp through a pattern mask having a line and space pattern having a width of 10 μm. Next, using a developer composed of a 2.38% by mass aqueous solution of tetramethylammonium hydroxide, development processing was carried out at 25 ° C. for 60 seconds, and then washed with running ultrapure water for 1 minute. At this time, the minimum ultraviolet irradiation amount capable of forming a line and space pattern having a width of 10 μm was measured. When this value is less than 800 J / m ² , it can be said that the sensitivity is good. This value is shown in Table 2 as radiation sensitivity.

  In Example 11, a PET film (Teijin Tetron film O3, thickness 188 μm) was used instead of the silicon substrate, and a coating film was formed by a bar coater. Pre-baking was performed in a clean oven at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. Subsequent evaluation was performed similarly to Examples 1-10 and 12.

[Evaluation of solvent resistance]
After applying the compositions of Examples 1 to 12 and Comparative Examples 1 to 2 on a silicon substrate using a spinner, pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. Formed. The obtained coating film was irradiated with ultraviolet rays by a mercury lamp so that the cumulative irradiation amount was 1,000 J / m ² . Next, this silicon substrate is heated on a hot plate at 150 ° C. for 30 minutes with respect to the samples of the examples and comparative examples, so that the coating film is heat-treated, and the thickness (T1) of the obtained cured film is determined. It was measured. And after immersing the silicon substrate in which this cured film was formed in dimethyl sulfoxide temperature-controlled at 70 degreeC for 20 minutes, the film thickness (t1) of the said cured film was measured, and the film thickness change rate by immersion {(T1-T1) / T1} × 100 [%] was calculated. It can be said that the solvent resistance is excellent when the absolute value of this value is less than 5%. The results are shown in Table 2.

[Evaluation of pencil hardness (surface hardness)]
About the board | substrate which has the cured film formed in said [solvent resistance evaluation], the pencil hardness (surface hardness) of the cured film was measured by the 8.4.1 pencil scratch test of JIS K-5400-1990. When this value is 3H or larger, it can be said that the surface hardness as the interlayer insulating film is good, and the positive radiation-sensitive resin composition used for forming the cured film has sufficient curability. The results are shown in Table 2.

[Evaluation of voltage holding ratio]
Examples 1 to 12 and Comparative Example using a spinner on a soda glass substrate on which a SiO ₂ film for preventing elution of sodium ions was formed on the surface, and an ITO (indium-tin oxide alloy) electrode was deposited in a predetermined shape After applying 1-2 compositions, prebaking was performed on a 90 ° C. hot plate for 2 minutes to form a coating film having a thickness of 2.0 μm. Development was carried out by a dip method in a 2.38 wt% tetramethylammonium hydroxide aqueous solution at 25 ° C. for 80 seconds. Next, using a high-pressure mercury lamp, the coating film was exposed to radiation containing wavelengths of 365 nm, 405 nm, and 436 nm at an integrated dose of 3,000 J / m ² without using a photomask. Subsequently, this substrate was heat-treated in a clean oven at 150 ° C. for 30 minutes under a post-bake temperature condition to form a cured film.

  Next, after spraying a 5.5 μm diameter bead spacer on the substrate having this cured film, the liquid crystal injection port is placed in a state where this is opposed to a soda glass substrate on which the ITO electrode is deposited in a predetermined shape. The four sides are bonded together using a sealing agent mixed with 0.8 mm glass beads, and a liquid crystal cell is sealed by injecting liquid crystal MLC6608 (trade name) manufactured by Merck and sealing the liquid crystal injection port. Produced.

This liquid crystal cell is placed in a constant temperature layer of 60 ° C., and a liquid crystal voltage holding ratio measurement system VHR-1A (trade name) manufactured by Toyo Technica is used to form a square wave with an applied voltage of 5.5 V and a measurement frequency of 60 Hz. The voltage holding ratio of the cell was measured. The results are shown in Table 2. Here, the voltage holding ratio is a value obtained by the following formula. The lower the value of the voltage holding ratio of the liquid crystal cell, the higher the possibility of causing a problem called “burn-in” when forming the liquid crystal panel. On the other hand, it can be said that the higher the value of the voltage holding ratio, the lower the possibility of occurrence of “burn-in” and the higher the reliability of the liquid crystal panel.
Voltage holding ratio (%) = (liquid crystal cell potential difference after 16.7 milliseconds from the reference time) / (voltage applied at 0 milliseconds [reference time]) × 100

  From the results shown in Table 2, the positive-type radiation-sensitive resin compositions prepared in Examples 1 to 12 have a high radiation sensitivity and obtain a cured film having a high surface hardness by heating at a low temperature for a short time. It was found that the cured film had excellent solvent resistance and voltage holding ratio. On the other hand, in Comparative Example 1 using a-1 which does not have a cyclic ether moiety in place of the [A] component, sufficient curability is not exhibited by low temperature and short time heating, and the solvent resistance of the cured film The property was also inferior. In Comparative Example 2 using a polyimide solution, pattern formation by exposure and development could not be performed, and sufficient curability was not exhibited by heating at a low temperature for a short time, and the solvent resistance of the cured film was poor. That is, it was found that by using the positive radiation sensitive resin composition of the present invention, an interlayer insulating film satisfying various properties such as required surface hardness can be formed at a lower temperature and in a shorter time than before. It was.

  The positive radiation sensitive resin composition of the present invention can form an interlayer insulating film by heating at a low temperature for a short time, and can form an interlayer insulating film having excellent solvent resistance and anti-seizure property. Therefore, it can be suitably used as a material for forming an interlayer insulating film of a flexible display.

Claims (7)

[A] (a1) a polymer containing at least one structural unit selected from the group consisting of structural units represented by the following formulas (1) and (1 ′), and [B] an acid generator A positive-type radiation-sensitive resin composition.

(In the formula (1), ^{R 1} is a hydrogen atom or a methyl group, X is a methylene group, an alkylene group having 2 to 20 carbon atoms, a phenylene group or naphthylene group, ^{R 2} represents a hydrogen atom, 1 to carbon atoms 20 alkyl groups, benzyl groups, phenyl groups or tolyl groups.
Wherein (1'), ^{R 1'is} a hydrogen atom or a methyl group, X'is a methylene group, an alkylene group having 2 to 20 carbon atoms, a phenylene group or a naphthylene group, ^{R 2'is} a hydrogen atom, a carbon It is an alkyl group, a benzyl group, a phenyl group, or a tolyl group of formula 1-20. ) The positive radiation-sensitive resin composition according to claim 1, wherein the polymer [A] further includes (a2) a structural unit represented by the following formula (2).

(In formula (2), Y is an oxygen atom or N—R ³ , and R ³ is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alicyclic alkyl group having 4 to 12 carbon atoms, a benzyl group, A phenyl group, a tolyl group or a naphthyl group.) The positive radiation sensitive resin composition according to claim 1 or 2, wherein the [A] polymer further comprises (a3) a structural unit represented by the following formula (3).

(In formula (3), R ⁴ is a hydrogen atom or a methyl group.) The [A] polymer is further (a4) at least one structural unit selected from the group consisting of structural units represented by the following formulas (4), (5), (6) and (6 ′), respectively. The positive radiation sensitive resin composition according to claim 1, claim 2, or claim 3.

(In the formula (4), ^{R 5} is a hydrogen atom or a methyl group, ^{R 6} is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, n is an integer from 0 to 12.
In Formula (5), R ⁷ is a hydrogen atom or a methyl group, and n is an integer of 0 to 12.
In Formula (6), R ⁸ is a hydrogen atom or a methyl group, R ⁹ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a halogen, and n is an integer of 0 to 12.
In formula (6 ′), R ^{8 ′} is a hydrogen atom or a methyl group, R ^{9 ′} is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a halogen, and n is an integer of 0 to 12. is there. )   The positive radiation sensitive resin composition according to any one of claims 1 to 4, which is used for forming an interlayer insulating film. (1) The process of forming the coating film of the positive radiation sensitive resin composition of Claim 5 on a board | substrate,
(2) A step of irradiating at least a part of the coating film formed in step (1),
(3) A method of forming an interlayer insulating film, comprising: a step of developing the coating film irradiated with radiation in step (2); and (4) a step of heating the coating film developed in step (3).   The interlayer insulation film formed using the positive radiation sensitive resin composition of Claim 5.