JP2019045622A - Photosensitive resin composition, pattern formation method, electronic device production method, polymer, and polymer production method - Google Patents

Abstract

To provide a photosensitive resin composition which has a good film-remaining property and reduces crack generation.SOLUTION: A specific polymer comprising a structural unit represented by a general formula (1) (specifically, N-(4-hydroxyphenyl) maleimide or the like), and a structural unit represented by a general formula (2) (specifically, 2-norbornene or the like) is used to prepare a photosensitive resin composition. Preferably, the specific polymer further comprises a structural unit represented by a chemical formula (3) (specifically, maleimide), and a structural unit represented by a chemical formula (4) (specifically, N-phenylmaleimide).SELECTED DRAWING: None

Description

  The present invention relates to a photosensitive resin composition, a method of forming a pattern, a method of manufacturing an electronic device, a polymer, and a method of manufacturing a polymer.

A large number of studies have been made on photosensitive resin compositions capable of forming a pattern, for the purpose of being used for production of electronic devices and the like.
As an example of examination, the photosensitive resin composition using the polymer which contains a maleimide structure in a principal chain is mentioned. Specifically, in Examples of Patent Document 1, as the resin, methacrylic acid, styrene, glycidyl methacrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate and N- (4 It is described that a photosensitive resin composition was prepared using a resin polymerized from -hydroxyphenyl) maleimide.

Patent No. 4127150

In recent years, miniaturization and complexity of electronic devices have been advanced. Along with that, higher performance is also required for photosensitive resin compositions.
However, according to the findings of the present inventors, in the conventional photosensitive resin composition, the residual film of the pattern after exposure and development was not necessarily satisfactory. Specifically, in the case of, for example, a positive photosensitive resin composition, the unexposed portion to be a residual film as a pattern after exposure and development may actually be dissolved and a pattern may not be formed satisfactorily. The
Moreover, when the conventional photosensitive resin composition formed the coating film, the crack (crack) might arise on the surface.

  The present invention has been made in view of such circumstances. That is, it is an object of the present invention to obtain a photosensitive resin composition having a good residual film property and reduced occurrence of cracks.

  MEANS TO SOLVE THE PROBLEM The present inventors discovered that the said subject could be achieved by using resin containing two specific types of structural units as resin in a photosensitive resin composition as a result of earnest examination, and completed this invention.

According to the invention
A photosensitive resin composition is provided which comprises a polymer comprising a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2).

一般式（１）において、
Ｒは、１価の置換基を表し、
ｍは、１〜３の整数を表し、
ｎは、０〜４の整数を表す。
ただし、ｍ＋ｎは、５以下である。
一般式（２）において、
Ｒ^１、Ｒ^２、Ｒ^３およびＲ^４は、それぞれ独立に、水素原子、または、カルボキシル基以外の１価の有機基を表し、
ｎは、０〜２の整数を表す。

In the general formula (1),
R represents a monovalent substituent,
m represents an integer of 1 to 3;
n represents an integer of 0 to 4;
However, m + n is 5 or less.
In the general formula (2),
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group other than a carboxyl group,
n represents an integer of 0 to 2;

Moreover, according to the present invention,
Forming a photosensitive resin film using the photosensitive resin composition,
Exposing the photosensitive resin film;
The pattern formation method is provided including the process of developing the said photosensitive resin film.

Moreover, according to the present invention,
A method of manufacturing an electronic device is provided, including the method of forming a pattern.

Moreover, according to the present invention,
There is provided a polymer comprising a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2).

一般式（１）において、
Ｒは、１価の置換基を表し、
ｍは、１〜３の整数を表し、
ｎは、０〜４の整数を表す。
ただし、ｍ＋ｎは、５以下である。
一般式（２）において、
Ｒ^１、Ｒ^２、Ｒ^３およびＲ^４は、それぞれ独立に、水素原子、または、カルボキシル基以外の１価の有機基を表し、
ｎは、０〜２の整数を表す。

In the general formula (1),
R represents a monovalent substituent,
m represents an integer of 1 to 3;
n represents an integer of 0 to 4;
However, m + n is 5 or less.
In the general formula (2),
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group other than a carboxyl group,
n represents an integer of 0 to 2;

Moreover, according to the present invention,
A process for producing the polymer, wherein
Charging a first solution containing at least a monomer represented by the following general formula (m2) and a polymerization initiator into a reaction vessel;
A start step of raising the temperature of the first solution to start a polymerization reaction;
Adding a second solution containing at least a monomer represented by the following general formula (m1) and not containing a monomer represented by the following general formula (m2) into the reaction vessel: production of a polymer A method is provided.

一般式（ｍ１）において、
Ｒは、１価の置換基を表し、
ｍは、１〜３の整数を表し、
ｎは、０〜４の整数を表す。
ただし、ｍ＋ｎは、５以下である。
一般式（ｍ２）において、
Ｒ^１、Ｒ^２、Ｒ^３およびＲ^４は、それぞれ独立に、水素原子、または、カルボキシル基以外の１価の有機基を表し、
ｎは、０〜２の整数を表す。

In the general formula (m1),
R represents a monovalent substituent,
m represents an integer of 1 to 3;
n represents an integer of 0 to 4;
However, m + n is 5 or less.
In the general formula (m2),
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group other than a carboxyl group,
n represents an integer of 0 to 2;

  According to the present invention, a photosensitive resin composition having good residual film properties and reduced occurrence of cracks can be obtained.

Hereinafter, embodiments of the present invention will be described in detail.
In the present specification, the notation “a to b” in the description of the numerical range indicates a or more and b or less unless otherwise specified.
In the notation of the group (atomic group) in the present specification, the notation not describing whether substituted or unsubstituted is intended to encompass both those having no substituent and those having a substituent. For example, the "alkyl group" includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
The expression "(meth) acrylic" in the present specification represents a concept including both acrylic and methacrylic. The same applies to similar notations such as "(meth) acrylate".

<Photosensitive resin composition>
The photosensitive resin composition of the present embodiment contains a polymer containing a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2).

In the general formula (1),
R represents a monovalent substituent,
m represents an integer of 1 to 3;
n represents an integer of 0 to 4;
However, m + n is 5 or less.
In the general formula (2),
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group other than a carboxyl group,
n represents an integer of 0 to 2;

It is not always clear why the photosensitive resin composition of the present embodiment contains the polymer to improve the residual film properties and reduce the occurrence of cracks. However, this reason is estimated as follows.
There are various causes for the occurrence of cracks, but it is considered that the mechanical strength of the resin is related to one of the factors. According to the findings of the present inventors, it is not easy to obtain a polymer of high molecular weight (of sufficient chain length) with monomers of general formula (1) alone (or monomers of general formula (2) alone). Only polymers of short chain length can be obtained. Polymers of short chain length have insufficient mechanical strength and are prone to cracking due to environmental changes such as heating, cooling, and development. On the other hand, the monomer of the general formula (1) and the monomer of the general formula (2) are easily copolymerized, and a polymer of high molecular weight (long chain length) can be easily obtained. That is, it is presumed that the mechanical strength of the polymer can be sufficiently increased, which contributes to the reduction of cracks.
With regard to residual film property, dissolution in the developer is appropriately suppressed by the interaction of the phenol structure in the structural unit represented by the general formula (1) with the photosensitizer (diazoquinone compound etc. described later). It is estimated that the residual film property is improved by being carried out.

  The component which the photosensitive resin composition of this embodiment may contain is demonstrated.

[polymer]
The photosensitive resin composition of the present embodiment contains a polymer containing a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2). The present invention is also an invention relating to this polymer.
Hereinafter, this polymer is also referred to as "specific polymer".

In the general formula (1),
R represents a monovalent substituent,
m represents an integer of 1 to 3;
n represents an integer of 0 to 4;
However, m + n is 5 or less.
In the general formula (2),
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group other than a carboxyl group,
n represents an integer of 0 to 2;

The structural unit represented by the general formula (1) will be described.
The monovalent substituent of R may be arbitrary and includes a halogen atom, a hydroxy group, a cyano group, an amino group, a monovalent organic group and the like.
When R is a monovalent organic group, examples of the organic group include an alkyl group, a cycloalkyl group, an alkoxy group, an aryl group, an aralkyl group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group and the like. These may be further substituted by another substituent (such as a hydroxy group or a halogen atom).
The alkyl group may be linear or branched, and examples thereof include alkyl groups having 1 to 20 carbon atoms, preferably linear and branched alkyl groups having 1 to 12 carbon atoms.
As said cycloalkyl group, a C3-C8 cycloalkyl group can be mentioned, for example.
The alkoxy group may be linear, branched or cyclic, and is, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 6 carbon atoms, 3 to 3 carbon atoms Mention may be made of 8 cyclic alkoxy groups.
n is preferably 0 or 1, more preferably 0.
m is preferably 1.

  The structural unit represented by the general formula (1) preferably includes a structural unit represented by the following chemical formula (1-1).

The specific polymer may contain plural kinds of structural units represented by the general formula (1).
The content of the structural unit represented by the general formula (1) is preferably 5 to 40 mol%, more preferably 5 to 30 mol%, based on the total structural units of the specific polymer.
The content of the structural unit represented by the general formula (1) in the specific polymer, can either be measured by means of a charged monomer amount and the amount of residual monomer in the polymer synthesis (polymerization), the ^{13 C-NMR} measurements It can also be determined from the peak area. The same applies to other structural units.

The structural unit represented by the general formula (2) will be described.
Specific examples of the monovalent organic group represented by R ¹ , R ² , R ³ and R ⁴ include the same groups as those in the case where R in the general formula (1) is a monovalent organic group. However, the carboxyl group is excluded as a monovalent organic group.
As R ¹ , R ² , R ³ and R ⁴ , a hydrogen atom is preferable.
n is preferably 0 or 1, more preferably 0.

The structural unit represented by the general formula (2) preferably does not contain a crosslinkable group. In other words, R ¹ , R ² , R ³ and R ⁴ in the structural unit represented by the general formula (2) do not contain a crosslinkable group.
Here, "crosslinkable group" typically refers to a thermally crosslinkable group that can form a crosslinked structure by heat treatment. Specific examples thereof include an epoxy group, an oxetanyl group, an acid anhydride group, and a group containing an ethylenically unsaturated double bond. Such a crosslinkable group can form a crosslinked structure with each other by heat treatment or the like, can self-polymerize, or can form a crosslinked structure via a crosslinking agent.

The specific polymer may contain plural kinds of structural units represented by the general formula (2).
The content of the structural unit represented by the general formula (2) is preferably 10 to 95% by mole, more preferably 20 to 60% by mole, based on the total structural units of the specific polymer.

  The specific polymer preferably further contains a structural unit (maleimide structural unit) represented by the following chemical formula (3).

When the specific polymer contains the structural unit represented by the chemical formula (3), improvement in developability can also be expected in addition to the improvement of the residual film property and the reduction of the occurrence of cracks.
The residual film property is incompatible with the developing solution, and the developing property is incompatible with the developing solution. Therefore, the maleimide is probably weaker than the carboxylic acid (mild) (mild) ) It is presumed that the residual film property and the developability can be adjusted in an appropriate manner by having a Br ス テ ッ ド nsted acid and having an appropriate alkali solubility.
Further, compared with the structural unit of the general formula (1), since the structural unit of the chemical formula (3) has no substituent, the polymer has high polymerizability, and it can be expected that the polymer having high molecular weight can be easily obtained.

  When the specific polymer contains a structural unit represented by chemical formula (3), its content is preferably 10 to 50 mol%, more preferably 20 to 40 mol%, based on the total structural units of the specific polymer.

  The specific polymer preferably further contains a structural unit represented by the following general formula (4).

In the general formula (4), R ^c represents a monovalent organic group containing a cyclic structure.
As a monovalent organic group containing the cyclic structure of R ^c , a monocyclic or polycyclic cycloalkyl group, an aryl group, an aralkyl group and the like can be mentioned. These may be further substituted by another substituent (such as an alkyl group, a hydroxy group or a halogen atom).
As R ^c , in particular, an aryl group is preferable from the viewpoint of further reducing a crack and improving the developability.
As a cycloalkyl group of R ^c , for example, a monocyclic cycloalkyl group having 3 to 8 carbon atoms can be mentioned.
Examples of the aryl group of R ^c include those having 6 to 10 carbon atoms, such as a phenyl group and a naphthyl group.
Examples of the aralkyl group of R ^c include those having 7 to 11 carbon atoms such as benzyl group and naphthylmethyl group.

  When a specific polymer contains the structural unit represented by General formula (4), the content is preferably 10 to 70 mol%, more preferably 15 to 60 mol%, in the total structural units of the specific polymer.

The specific polymer may contain other structural units not described above.
However, the specific polymer preferably does not contain a structural unit having an oxetanyl group. When the specific polymer does not contain a structural unit having an oxetanyl group, improvement in developability can be expected.

Although the weight average molecular weight (Mw) of a specific polymer is not specifically limited, Preferably it is 10000 or more, More preferably, it is 10000-50000, More preferably, it is 10000-30000. By setting Mw to 10000 or more, as a result of the chain length of a polymer becoming moderately long, it is estimated that the mechanical strength of a film improves. Therefore, it is considered that the crack can be further reduced.
Also, the degree of dispersion (weight average molecular weight Mw / number average molecular weight Mn) of the specific polymer is typically 1.2 to 5.0, preferably 1.5 to 3.0.
Mw and Mn can be determined by gel permeation chromatography (GPC) measurement using polystyrene as a standard substance.

The alkali dissolution rate of the specific polymer is preferably 300 to 20,000 Å / sec, and more preferably 400 to 15,000 Å / sec. By setting it as such an alkali dissolution rate, coexistence of developability and residual film property can be made more highly advanced.
For the method of measuring the alkali dissolution rate, refer to the examples described below.

[Method of producing specific polymer]
The specific polymer can be produced by appropriately applying known polymer synthesis techniques, but can be produced, for example, through the following steps.
Charging a first solution containing at least a monomer represented by the following general formula (m2) and a polymerization initiator into a reaction vessel;
A start step of raising the temperature of the first solution to start the polymerization reaction;
Adding a second solution containing at least a monomer represented by the following general formula (m1) and not containing a monomer represented by the following general formula (m2) into the reaction vessel.

The definitions of R, m and n in General Formula (m1) are the same as those in General Formula (1).
The definitions of R ¹ , R ² , R ³ , R ⁴ and n in General Formula (m2) are the same as those in General Formula (2).

  The monomer represented by the general formula (m2) (which becomes a structural unit of the general formula (2) by polymerization) is the monomer represented by the general formula (m1) (which becomes a structural unit of the general formula (1) by polymerization) It is considered to be difficult to polymerize compared to Therefore, when the monomer represented by the general formula (m1) and the monomer represented by the general formula (m2) are all mixed at one time to start the polymerization reaction, the monomer represented by the general formula (m1) is While being preferentially polymerized, the monomer represented by the general formula (m2) may not be consumed so much, and the desired amount of the structural unit of the general formula (1) may not be incorporated into the polymer.

  Therefore, as described above, first, the monomer represented by the general formula (m2) is charged into the reaction vessel, the polymerization reaction is started, and then the second solution containing the monomer represented by the general formula (m1) It is considered that the addition of the component (a) makes it easy to maintain the amount of the monomer represented by the general formula (m1) and the amount of the monomer represented by the general formula (m2) in a constant amount in the polymerization system. As a result, it is considered that it becomes easy to obtain a specific polymer of a desired composition.

  The method for producing the specific polymer will be described more specifically.

Feeding Step The first solution contains at least the monomer represented by the general formula (m2) and a polymerization initiator, but may contain other components.
As a polymerization initiator, a radical polymerization initiator, for example, a known azo compound initiator or an organic peroxide initiator can be used.
The other components correspond to the monomer represented by the general formula (m1), the monomer corresponding to the structural unit represented by the above general formula (3), and the structural unit represented by the above general formula (4) Monomers, molecular weight regulators, chain transfer agents (eg, known thiol compounds), and the like.
The above components are uniformly mixed and dissolved using an appropriate organic solvent as a solvent. As the organic solvent, ester solvents, ketone solvents, ether solvents and the like can be used. More specifically, methyl ethyl ketone (MEK), propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethyl ether, tetrahydrofuran (THF), toluene, ethyl acetate, butyl acetate and the like can be mentioned. Two or more solvents may be mixed and used as the organic solvent.
Moreover, it is preferable to reduce the dissolved oxygen in the system by nitrogen bubbling or the like for the first solution.

Starting Step By raising the temperature of the first solution in the reaction vessel, the polymerization initiator in the first solution is cleaved, and the polymerization reaction starts. The temperature is raised, for example, to 50 to 90 ° C. depending on the cleavability of the polymerization initiator.

-Additive process The second solution in the additive process contains the monomer represented by the general formula (m1) and is not particularly limited as long as it does not contain the monomer represented by the following general formula (m2), A monomer corresponding to the structural unit represented by General Formula (3), a monomer corresponding to the structural unit represented by General Formula (4) described above, and the like may be additionally contained. In addition, additional polymerization initiators, chain transfer agents, molecular weight modifiers and the like may be contained. Similar to the first solution, these components can be uniformly mixed and dissolved with an appropriate organic solvent to obtain a second solution.
The second solution is dropped into the reaction vessel, for example, over 1 to 24 hours.
By each process as described above, a solution containing a specific polymer can be obtained.

  The solution containing the specific polymer is poured into a large amount of a poor solvent (for example, a mixed solution of pure water and methanol) to precipitate the specific polymer, which is then collected by filtration, washed and dried to obtain residual monomers and the like. It is possible to obtain a high purity specific polymer that has been removed.

[Polymer other than specific polymer]
The photosensitive resin composition of the present embodiment contains at least a specific polymer (a polymer containing a structural unit represented by the chemical formula (1) and a structural unit represented by the general formula (2)), but other than that It may contain a polymer.
Examples of such polymers include known alkali-soluble resins such as novolak resins, polyhydroxystyrenes and poly (meth) acrylic acid. Among these, novolak resins are preferable in terms of cost, availability, compatibility with the above-described polymers, and the like.
When the photosensitive resin composition contains such a polymer, the amount thereof is preferably 1 to 30 parts by mass, more preferably 3 to 20 parts by mass with respect to 100 parts by mass of the above-mentioned polymer.

[Photosensitizer]
The photosensitive resin composition of the present embodiment preferably contains a photosensitizer.
The photosensitizer generates an acid upon irradiation with light such as g-line, i-line and deep ultraviolet light.

  Specifically as photosensitive agents, photosensitive diazoquinone compounds, onium salts (sulfonium salts, iodonium salts, etc.), sulfonic acid ester compounds, oxime sulfonate compounds, diazodisulfone compounds, 2-nitrobenzyl ester compounds, N-iminosulfonate compounds And imidosulfonate compounds, 2,6-bis (trichloromethyl) -1,3,5-triazine compounds, dihydropyridine compounds and the like.

In particular, when the photosensitive resin composition is a positive type (when the pattern development is developed with an alkali developer after exposure, the exposed portion dissolves), the photosensitizer preferably contains a diazoquinone compound. Thereby, it is possible to obtain a positive pattern having good sensitivity and resolution.
As a diazoquinone compound, 1 type, or 2 or more types of compounds can be used among what is shown below, for example.

In each of the above diazoquinone compounds, Q is any one of the structures represented by the following formulas (a), (b) and (c), or a hydrogen atom. However, at least one of Q of each diazoquinone compound is any one of the structures represented by the following formula (a), the following formula (b) and the following formula (c). Moreover, n is an integer of 1-5.
The Q of the diazoquinone compound preferably contains the following formula (a) or the following formula (b). Thereby, the transparency of the photosensitive resin composition can be improved. Therefore, the appearance of the photosensitive resin composition can be improved.

  The amount of the photosensitizer in the photosensitive resin composition is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, with respect to 100 parts by mass of the polymer (including not only the specific polymer but also other polymers). It is.

[Silane coupling agent]
The photosensitive resin composition of the present embodiment preferably contains a silane coupling agent. Thereby, the adhesion to the substrate can be enhanced.

  As a silane coupling agent, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropyl Methyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl)- 3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane 3-Aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxypropyl) tetrasulfide, 3-isocyanatepropyltritriol Examples include, but not limited to, ethoxysilane, and silicon compounds obtained by reacting a silicon compound having an amino group with an acid dianhydride or an acid anhydride.

The silane coupling agent may be used alone or in combination of two or more.
When the photosensitive resin composition contains a silane coupling agent, the amount is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the polymer (including not only specific polymers but also other polymers). And more preferably 1 to 20 parts by mass. By setting it as the said range, adhesiveness and the preservability of the photosensitive resin composition can be made compatible.

[Surfactant]
The photosensitive resin composition of the present embodiment preferably contains a surfactant. By including the surfactant, the coatability at the time of obtaining the resin film by applying the photosensitive resin composition on the substrate becomes good. For example, radial striations that can form on the film during spin coating can be reduced.
As the surfactant, nonionic surfactants are particularly preferable.

  The surfactant includes, for example, a compound containing a fluorine-containing group (such as a fluorinated alkyl group) or a silanol group, or a compound having a siloxane bond as a main skeleton. In the present embodiment, a nonionic fluorine-based surfactant or silicone-based surfactant is preferred. As the fluorine-based surfactant, for example, Megafac F-171, F-173, F-444, F-470, F-471, F-475, F-482, F-477, F manufactured by DIC Corporation can be used. -554, F-556 and F-557, Nobek FC4430 and FC4432 manufactured by Sumitomo 3M Limited, and the like, but not limited thereto.

Only one surfactant may be used, or two or more surfactants may be used in combination.
When a surfactant is used, its amount is preferably 0.01 to 10 parts by weight with respect to 100 parts by weight of the polymer (including not only specific polymers but also other polymers).

[solvent]
The photosensitive resin composition of the present embodiment is preferably obtained by dissolving or dispersing the above-mentioned various components (and, in some cases, the other components described below) in a solvent.
The solvent is preferably an organic solvent. As the organic solvent, N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, dimethylsulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene Glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl 1,3-butylene glycol acetate, 1,3-butylene glycol 3-monomethyl ether, methyl pyruvate, ethyl pyruvate and methyl 3-methoxypro Peonate etc. are mentioned.

A solvent may use only 1 type and may use 2 or more types together.
The amount of the solvent used is such that the concentration of the non-volatile component of the photosensitive resin composition is preferably 3 to 50% by mass, more preferably 5 to 40% by mass, and more preferably 10 to 30% by mass.

[Other ingredients]
The photosensitive resin composition of this embodiment may also contain various components other than the above. For example, components such as a dissolution accelerator, an antioxidant, a filler, a photopolymerization initiator, a sensitizer and the like may be further included within the range not impairing the effects of the present invention.
The photosensitive resin composition of the present embodiment may or may not contain a crosslinking agent, but preferably does not contain a crosslinking agent.

According to the photosensitive resin composition of the present embodiment, as described above, the effects of improving the residual film property and reducing the occurrence of cracks can be expected. Besides these effects, the developability is improved (such as reduction of development residue) and the thermal flow resistance is improved (the pattern is not deformed even if the formed pattern is heated) by optimizing the composition of the polymer. Can also be expected effects.
In addition, the specific polymer has low absorption of ultraviolet light and has high ultraviolet light transmittance due to its structure. That is, the irradiation light is not absorbed wastefully. This can be expected to improve the sensitivity of the composition and improve the pattern shape.

<Pattern formation method>
An embodiment of a pattern forming method using the photosensitive resin composition described above will be described.
The pattern formation method of the present embodiment includes the steps of forming a photosensitive resin film using the photosensitive resin composition described above, exposing the photosensitive resin film, and developing the photosensitive resin film.

The process of forming a photosensitive resin film using a photosensitive resin composition is demonstrated.
The photosensitive resin film is typically formed by providing a photosensitive resin composition on a suitable substrate. The substrate is not particularly limited, and examples thereof include silicon wafers, ceramic substrates, aluminum substrates, SiC wafers, GaN wafers, copper-clad laminates and the like. The substrate includes, in addition to the unprocessed substrate, for example, a substrate on which a semiconductor element or a display element is formed. The substrate surface may be treated with an adhesion promoter such as a silane coupling agent in order to improve adhesion.
Examples of methods for providing the photosensitive resin composition on a substrate include spin coating using a spinner, spray coating using a spray coater, immersion, printing, roll coating, an inkjet method, and the like. Among these, spin coating is preferred.
In addition, after providing a photosensitive resin composition to a board | substrate, it is preferable to heat a board | substrate with a hot plate (prebaking). The temperature for prebaking is usually 80 to 140 ° C, preferably 90 to 120 ° C. The pre-baking time is usually about 30 to 600 seconds, preferably about 30 to 300 seconds.
The thickness of the photosensitive resin film is appropriately adjusted, for example, between 0.1 and 100 μm.

The process of exposing the photosensitive resin film will be described.
By irradiating the photosensitive resin film with an actinic ray for exposure through a suitable photomask, a latent image reflecting the pattern of the photomask can be formed on the photosensitive resin film.
As the actinic ray for exposure, for example, X-ray, electron beam, ultraviolet ray, visible light and the like can be used. In terms of wavelength, actinic radiation of 200 to 500 nm is preferred. From the viewpoint of pattern resolution and handling, the light source is preferably a mercury lamp g-line, h-line or i-line, and particularly preferably i-line. Also, two or more light beams may be mixed and used. As the exposure apparatus, a contact aligner, a mirror projection or a stepper is preferable.
In addition, after exposure, the photosensitive resin film may be heated again as required (post-exposure baking: Post Exposure Bake). The temperature is, for example, 80 to 150 ° C, preferably 90 to 120 ° C. The time is, for example, 30 to 600 seconds, preferably 30 to 300 seconds.

The process of developing the photosensitive resin film will be described.
The development can be performed using a developer, for example, by a method such as immersion method, paddle method, rotary spray method and the like. By development, an exposed portion (in the case of positive type) or an unexposed portion (in the case of negative type) is eluted and removed from the coating film, and a patterned resin film can be obtained.
An alkaline aqueous solution is preferably used as the developer. Specifically, (i) inorganic alkali aqueous solution such as sodium hydroxide, sodium carbonate, sodium silicate, ammonia etc. (ii) aqueous solution of organic amine such as ethylamine, diethylamine, triethylamine, triethanolamine etc., (iii) tetramethyl ammonium Examples include aqueous solutions of quaternary ammonium salts such as hydroxide and tetrabutylammonium hydroxide.
For example, a water-soluble organic solvent such as methanol or ethanol, or a surfactant may be added to the developer.
As a developing solution, tetramethyl ammonium hydroxide aqueous solution is preferable. The concentration of tetramethylammonium hydroxide in this aqueous solution is preferably 0.1 to 10% by mass, more preferably 0.3 to 5% by mass.

In addition, you may wash by rinse agent etc. after image development processing. Examples of the rinse solution include distilled water, methanol, ethanol, isopropanol, propylene glycol monomethyl ether and the like. These can be used alone or in combination of two or more.
In addition, after development processing, whole surface exposure may be performed or post-baking processing may be performed.
The irradiation dose of the overall exposure is adjusted, for example, between 1 and 500 mJ / cm ² . The post-baking treatment can be performed, for example, at 100 to 200 ° C. for 5 to 15 minutes.

<Method of Manufacturing Electronic Device>
The pattern formation method described above can be applied to the manufacture of electronic devices.
For example, the semiconductor substrate can be processed by selectively etching the semiconductor substrate using the pattern obtained by the above-described method as an etching mask. That is, an electronic device can be manufactured by the process including the above-mentioned pattern formation method.
The specific polymer of this embodiment contains many structures having high etching resistance, such as an aryl moiety and a norbornane skeleton. Therefore, it is preferably applied to the etching mask.

  As mentioned above, although embodiment of this invention was described, these are the illustrations of this invention, and various structures other than the above can be employ | adopted. Furthermore, the present invention is not limited to the above-described embodiment, and modifications, improvements, and the like within the scope in which the object of the present invention can be achieved are included in the present invention.

  Embodiments of the present invention will be described in detail based on examples and comparative examples. The present invention is not limited to the examples.

<Synthesis of polymer>
Synthesis Example 1: Synthesis of Polymer 1
In a reaction vessel, 2-norbornene (75 mass% toluene solution, 21.3 g, 0.169 mol), maleimide (8.9 g, 0.092 mol), N-phenylmaleimide (15.9 g, 0.092 mol), A polymerization initiator V-601 (2.6 g, 0.011 mol) and 19.3 g of methyl ethyl ketone (hereinafter abbreviated as MEK, the same applies to other synthesis examples as well) made by Photopurex Co., Ltd. were added and stirred and dissolved.
Subsequently, after removing the dissolved oxygen in the system by nitrogen bubbling, it heated. When the internal temperature reached 60 ° C., maleimide (7.5 g, 0.077 mol), 4-hydroxyphenylmaleimide (10.7 g, 0.056 mol) and N-phenylmaleimide (13.4 g, 0.077 mol) A solution of 34.4 g of MEK and 16.02 g of propylene glycol monomethyl ether in a mixed solvent was added over 6 hours.
Thereafter, the temperature was raised to 70 ° C. and reaction was further performed for 3 hours. The reaction mixture was then cooled to room temperature and diluted by adding 100 g of MEK. The diluted solution was poured into a large amount of pure water / methanol mixed solution to precipitate a polymer. Next, the polymer was collected by filtration, washed with pure water, and vacuum dried at 120 ° C. for 16 hours.
The yield of the obtained polymer was 56.4 g, and the yield was 75%. The polymer obtained had a weight-average molecular weight Mw of 14,900, a degree of dispersion (weight-average molecular weight Mw / number-average molecular weight Mn) of 2.17, and an alkali dissolution rate of 8,000 Å / sec.

Synthesis Example 2: Synthesis of Polymer 2
In a reaction vessel, 2-norbornene (75% mass toluene solution, 21.0 g, 0.167 mol), maleimide (5.2 g, 0.054 mol), N-phenylmaleimide (9.3 g, 0.054 mol), A polymerization initiator V-601 (2.6 g, 0.011 mol) and 12.3 g of MEK manufactured by Photopure Chemical Industries, Ltd. were added, and the mixture was stirred and dissolved.
Subsequently, after removing the dissolved oxygen in the system by nitrogen bubbling, it heated. When the internal temperature reaches 60 ° C., maleimide (11.1 g, 0.114 mol), 4-hydroxyphenylmaleimide (21.1 g, 0.112 mol), and N-phenylmaleimide (10.1 g, 0.058 mol) A solution of 25.8 g of MEK and 31.7 g of propylene glycol monomethyl ether in a mixed solvent was added over 6 hours.
Thereafter, the temperature was raised to 70 ° C. and reaction was further performed for 3 hours. The reaction mixture was then cooled to room temperature and diluted by adding 100 g of MEK. The diluted solution was poured into a large amount of pure water / methanol mixed solution to precipitate a polymer. Then, the polymer was collected by filtration, further washed with pure water, and vacuum dried at 120 ° C. for 16 hours.
The yield of the obtained polymer was 45.4 g, and the yield was 61%. Further, the obtained polymer had a weight average molecular weight Mw of 11,000, a degree of dispersion (weight average molecular weight Mw / number average molecular weight Mn) of 1.98, and an alkali dissolution rate of 14,800 Å / sec.

Synthesis Example 3 Synthesis of Polymer 3
In a reaction vessel, 2-norbornene (75 mass% toluene solution, 21.0 g, 0.167 mol), maleimide (2.3 g, 0.023 mol), N-cyclohexylmaleimide (4.1 g, 0.023 mol), A polymerization initiator V-601 (2.6 g, 0.011 mol) and 6.9 g of MEK manufactured by Photopurex Co., Ltd. were added and stirred and dissolved.
Subsequently, after removing the dissolved oxygen in the system by nitrogen bubbling, it heated. When the internal temperature reaches 60 ° C., maleimide (14.0 g, 0.144 mol), 4-hydroxyphenylmaleimide (10.6 g, 0.056 mol), and N-cyclohexylmaleimide (25.9 g, 0.144 mol) A solution of 47.0 g of MEK and 15.8 g of propylene glycol monomethyl ether in a mixed solvent was added over 6 hours.
Thereafter, the temperature was raised to 70 ° C. and reaction was further performed for 3 hours. The reaction mixture was then cooled to room temperature and diluted by adding 100 g of MEK. The diluted solution was poured into a large amount of pure water / methanol mixed solution to precipitate a polymer. Then, the polymer was collected by filtration, further washed with pure water, and vacuum dried at 120 ° C. for 16 hours.
The yield of the obtained polymer was 62.0 g, and the yield was 83%. Further, the obtained polymer had a weight-average molecular weight Mw of 14,700, a dispersion degree (weight-average molecular weight Mw / number-average molecular weight Mn) of 2.12, and an alkali dissolution rate of 1,700 Å / sec.

Synthesis Example 4 Synthesis of Polymer 4
In a reaction vessel, 2-norbornene (75 mass% toluene solution, 19.0 g, 0.151 mol), norbornene carboxylic acid (60 mass% MEK solution, 23.2 g, 0.101 mol), N-phenylmaleimide (23. 9 g (0.138 mol), a polymerization initiator V-601 (2.3 g, 0.010 mol) manufactured by Wako Pure Chemical Industries, Ltd. and 18.4 g of MEK were added, and stirred and dissolved.
Next, after removing dissolved oxygen in the system by nitrogen bubbling, the system is warmed, and when the internal temperature reaches 60 ° C., 4-hydroxyphenylmaleimide (9.5 g, 0.050 mol), N-phenylmaleimide ( A solution of 11.0 g, 0.064 mol) in 28.3 g of MEK and 14.3 g of propylene glycol monomethyl ether was added over 6 hours.
Thereafter, the temperature was raised to 70 ° C. and reaction was further performed for 3 hours. The reaction mixture was then cooled to room temperature and diluted by adding 100 g of MEK. The diluted solution was poured into a large amount of pure water / methanol mixed solution to precipitate a polymer. Then, the polymer was collected by filtration, further washed with pure water, and vacuum dried at 120 ° C. for 16 hours.
The yield of the obtained polymer was 43.4 g, and the yield was 58%. Further, the obtained polymer had a weight average molecular weight Mw of 9,700, a dispersion degree (weight average molecular weight Mw / number average molecular weight Mn) of 1.96, and an alkali dissolution rate of 430 Å / sec.

Synthesis Example 5 Synthesis of Polymer 5
In a reaction vessel, 2-norbornene (75 mass% toluene solution, 21.3 g, 0.169 mol), a polymerization initiator V-601 (2.6 g, 0.011 mol) manufactured by Wako Pure Chemical Industries, Ltd. and 16.5 g of MEK Was added and dissolved by stirring.
Subsequently, after removing the dissolved oxygen in the system by nitrogen bubbling, it heated. When the internal temperature reached 70 ° C., maleimide (16.4 g, 0.169 mol), 4-hydroxyphenyl maleimide (10.7 g, 0.056 mol), and N-phenyl maleimide (29.3 g, 0.169 mol) A solution of 74.7 g of MEK and 16.0 g of propylene glycol monomethyl ether in a mixed solvent was added over 4 hours.
Thereafter, the temperature was raised to 80 ° C. and reaction was further performed for 3 hours. The reaction mixture was then cooled to room temperature and diluted by adding 62.5 g MEK. The diluted solution was poured into a large amount of pure water / methanol mixed solution to precipitate a polymer. Then, the polymer was collected by filtration and further washed with pure water, and then vacuum dried at 120 ° C. for 16 hours.
The yield of the obtained polymer was 62.5 g, and the yield was 83%. The polymer obtained had a weight average molecular weight Mw of 6,800, a degree of dispersion (weight average molecular weight Mw / number average molecular weight Mn) of 1.82, and an alkali dissolution rate of 7,800 Å / sec.

Synthesis Example 6: Synthesis of Polymer 6 (for Comparison)
In a reaction vessel, norbornene carboxylic acid (44.4 g, 0.321 mol), N-phenylmaleimide (31.0 g, 0.179 mol), a polymerization initiator V-601 (7.4 g, manufactured by Wako Pure Chemical Industries, Ltd.) 0.032 mol) and 29.6 g of MEK were added and stirred and dissolved.
Subsequently, after removing the dissolved oxygen in the system by nitrogen bubbling, it heated. When the internal temperature reached 70 ° C., a solution of N-phenylmaleimide (24.6 g, 0.142 mol) dissolved in 63.1 g of MEK was added over 4 hours.
Then, it was made to react at 70 degreeC for 3 hours. The reaction mixture was then cooled to room temperature and diluted by adding 133.3 g MEK. The diluted solution was poured into a large amount of pure water / methanol mixed solution to precipitate a polymer. Then, the polymer was collected by filtration and further washed with pure water, and then vacuum dried at 120 ° C. for 16 hours.
The yield of the obtained polymer was 65.7 g, and the yield was 66%. Further, the obtained polymer had a weight average molecular weight Mw of 6,800, a degree of dispersion (weight average molecular weight Mw / number average molecular weight Mn) of 1.91 and an alkali dissolution rate of 4,000 Å / sec.

Synthesis Example 7: Synthesis of Polymer 7 (for Comparison)
In a reaction vessel, norbornene carboxylic acid (28.1 g, 0.203 mol), N-phenylmaleimide (30.1 g, 0.174 mol), a polymerization initiator V-601 (7.8 g, manufactured by Wako Pure Chemical Industries, Ltd.) 0.034 mol) and 18.7 g of MEK were added and stirred and dissolved.
Subsequently, after removing the dissolved oxygen in the system by nitrogen bubbling, it heated. When the internal temperature reached 70 ° C., a solution of maleimide (13.2 g, 0.136 mol) and N-phenylmaleimide (28.7 g, 0.165 mol) dissolved in 73.5 g of MEK was added over 4 hours .
Thereafter, the temperature was raised to 80 ° C. and reaction was further performed for 3 hours. The reaction mixture was then cooled to room temperature and diluted by adding 133.3 g MEK. The diluted solution was poured into a large amount of pure water / methanol mixed solution to precipitate a polymer. Then, the polymer was collected by filtration and further washed with pure water, and then vacuum dried at 120 ° C. for 16 hours.
The yield of the obtained polymer was 88.3 g, and the yield was 88%. Further, the obtained polymer had a weight average molecular weight Mw of 7,800, a degree of dispersion (weight average molecular weight Mw / number average molecular weight Mn) of 2.20, and an alkali dissolution rate of 3,600 Å / sec.

Synthesis Example 8 Synthesis of Polymer 8 (for Comparison)
In a reaction vessel, norbornene carboxylic acid (30.7 g, 0.222 mol), N-phenylmaleimide (14.4 g, 0.083 mol), a polymerization initiator V-601 (5.1 g, manufactured by Wako Pure Chemical Industries, Ltd.) 0.022 mol) and 20.5 g of MEK were added and stirred and dissolved. Subsequently, after removing the dissolved oxygen in the system by nitrogen bubbling, it heated. When the internal temperature reaches 70 ° C., N-phenylmaleimide (16.4 g, 0.094 mol), 4-hydroxyphenylmaleimide (8.4 g, 0.044 mol), 41.9 g of MEK and 12.6 g of propylene glycol monomethyl ether The solution dissolved in the mixed solvent of was added over 4 hours.
Thereafter, the temperature was raised to 80 ° C. and reaction was further performed for 3 hours. The reaction mixture was then cooled to room temperature and diluted by adding 100 g of MEK. The diluted solution was poured into a large amount of pure water / methanol mixed solution to precipitate a polymer. Then, the polymer was collected by filtration and further washed with pure water, and then vacuum dried at 120 ° C. for 16 hours.
The yield of the obtained polymer was 58.5 g, and the yield was 78%. Further, the obtained polymer had a weight average molecular weight Mw of 5,100, a degree of dispersion (weight average molecular weight Mw / number average molecular weight Mn) of 1.93, and an alkali dissolution rate of 28,800 Å / sec.

  A summary of each polymer is shown in the table below.

In the above table, the abbreviations of the compositions are as follows.
NB: 2-norbornene NC: 5-norbornene-2-carboxylic acid MI: maleimide PMI: N-phenylmaleimide CMI: N-cyclohexylmaleimide PhOHMI: N- (4-hydroxyphenyl) maleimide

In addition, the weight average molecular weight (Mw) and number average molecular weight (Mn) of each polymer used the polystyrene conversion value calculated | required from the analytical curve of standard polystyrene (PS) obtained by GPC measurement. The measurement conditions are as follows.
Device: gel permeation chromatography device manufactured by Tosoh Corp. HLC-8320GPC
Column: Tosoh Corp. TSK-GEL Supermultipore HZ-M
Detector: RI detector for liquid chromatogram Measurement temperature: 40 ° C
Solvent: THF
Sample concentration: 2.0 mg / mL

Further, the alkali dissolution rate of each polymer is a value measured by the following procedure.
(1) First, a solution was prepared by dissolving the obtained polymer in a mixed solvent of propylene glycol monomethyl ether acetate: propylene glycol monomethyl ether = 80: 20 (mass ratio) to a solid content of 25% by mass.
(2) The above solution was spin-coated on a silicon wafer and heat-treated at 100 ° C. for 120 seconds to obtain a polymer film having a film thickness H of 2.0 μm.
(3) The above polymer film was impregnated with a 0.5 mass% tetramethylammonium hydroxide aqueous solution at 23 ° C., and the time T until the polymer film was visually eliminated was measured. The film thickness H / time T was calculated as the dissolution rate (Å / sec) on the basis of the measurement value obtained by this.

<Preparation of Photosensitive Resin Composition>
Example 1
Polymer 1,4,4 '-(1- {4- [1- (4-hydroxyphenyl) -1-methylethyl] phenyl} ethylidene) bisphenol and 1,2-naphthoquinonediazide-5 synthesized by Synthesis Example 1 -Preparation of esterified products with sulfonyl chloride (manufactured by Daitoke Mix Co., Ltd .: PA-15), KBM-403 (manufactured by Shin-Etsu Silicone Co., Ltd.) and F-556 (manufactured by DIC Corporation) in parts by mass shown in Table 2 It melt | dissolved so that it might become 20 mass% of solid components in the mixed solvent of propylene glycol monomethyl ether acetate (PGMEA): propylene glycol monomethyl ether (PGME) = 80:20 (mass ratio). The resultant was filtered with a PTFE filter having a pore size of 0.2 μm to prepare a positive photosensitive resin composition.
(Examples 2 to 6, Comparative Examples 1 to 3)
A positive photosensitive resin composition was prepared in the same manner as in Example 1 except that each component and the amount (parts by mass) thereof were as described in Table 2.
In addition, as a novolak resin of Example 6, PR-54919 (m.p-cresol novolac resin manufactured by Sumitomo Bakelite Co., Ltd.) was used.

<Evaluation of photosensitive resin composition>
(Formation of thin film pattern)
The thin film pattern was formed as follows. First, the obtained photosensitive resin composition was spin-coated on a 4-inch silicon wafer (rotation speed 300-2500 rpm) and baked on a hot plate at 100 ° C. for 120 seconds to obtain a thin film A of about 2 μm thickness .
This thin film A was exposed to g / h / i broadband light through a hole pattern mask with a diameter of 10 μm, using g + h + i line mask aligner (PLA-501F) manufactured by Canon Inc. The exposure dose was 300 mJ / cm ² .
Thereafter, development was carried out at 23 ° C. using an aqueous solution of tetramethylammonium hydroxide (TMAH) as a developer to obtain a patterned thin film B. The concentration of the developer and the development time were as shown in Table 2 in order to set conditions suitable for the development rate of each polymer.
This thin film B was exposed on the entire surface at 300 mJ / cm ² with PLA-501F and then post-baked by heating on a hot plate at 150 ° C. for 10 minutes to obtain a thin film with a pattern C.

(Evaluation of residual film rate (after development and post bake))
From the film thicknesses of thin film A, thin film B and thin film C obtained by forming the above-mentioned thin film pattern, the residual film ratio was calculated from the following equation.
Residual film ratio after development (%) = [Thin film thickness (μm) / Thin film thickness (μm)] × 100
Remaining film ratio (%) after post-baking = [Thin film thickness (μm) / Thin film thickness (μm)] × 100

(Crack evaluation)
In the above-mentioned thin film pattern formation, it was evaluated whether a crack could be seen on the coating film surface. The evaluation criteria are the following three levels.
3: No cracking after post-baking (thin film C).
2: A crack is observed after development or after post-baking (Thin films B and C).
1: A crack is seen immediately after the application of the composition (thin film A).

(Developability evaluation)
The 10 μm diameter hole pattern after development was evaluated based on the following criteria.
3: No residue was found.
2: The residue was patternable of what was seen.
1: The film could not be evaluated because the film was completely dissolved or the resolution was low.

(Thermal flow resistance evaluation)
The 10 μm diameter hole patterns before and after the post bake were evaluated based on the following criteria.
2: There was no change in the shape.
1: There were remarkable changes in pattern deformation and CD (critical dimension).

(Evaluation of transmittance)
The same operation as that described above (formation of thin film pattern) was performed using a 1737 glass substrate (100 mm in length, 100 mm in width) manufactured by Corning Inc. and not performing exposure and development. Thereby, a thin film without a pattern was obtained on a glass substrate.
About this thin film, the transmittance | permeability (%) in wavelength 400 nm of light was measured using the ultraviolet-visible light spectrophotometer, and the numerical value converted into film thickness 3 micrometers was made into the transmittance | permeability.

  The formulation information of the compositions of the respective examples and comparative examples, the information on the used developer, and the evaluation results are summarized in Table 2.

  As can be seen from Table 2, the structural unit (PhOHMI: N- (4-hydroxyphenyl) maleimide) represented by the general formula (1) and the structural unit (NB: 2-norbornene) represented by the general formula (2) The photosensitive resin composition containing a polymer containing both of them showed good residual film ratio (residual film ratio after development and residual film ratio after post-baking), and showed good results also for cracks (Examples 1 to 6).

In particular, the structural unit (MI: maleimide) represented by the chemical formula (3) as the additional structural unit, or the structural unit (PMI: N-phenyl maleimide) in which R ^c is an aryl group in the general formula (4) In the case of including the above, the developability and the thermal flow resistance tended to be excellent.

  On the other hand, a photosensitive resin composition containing a polymer not containing at least one of the structural unit represented by the general formula (1) and the structural unit represented by the general formula (2) is satisfactory in terms of residual film ratio and cracks. It was not a result (comparative examples 1 to 3).

  In addition, regarding the transmittance | permeability, all the examples showed high transparency.

Claims (18)

The photosensitive resin composition containing the polymer containing the structural unit represented by following General formula (1), and the structural unit represented by following General formula (2).

In the general formula (1),
R represents a monovalent substituent,
m represents an integer of 1 to 3;
n represents an integer of 0 to 4;
However, m + n is 5 or less.
In the general formula (2),
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group other than a carboxyl group,
n represents an integer of 0 to 2; The photosensitive resin composition according to claim 1, wherein
The photosensitive resin composition in which the said polymer contains the polymer which does not contain the structural unit which has oxetanyl group. It is the photosensitive resin composition of Claim 1 or 2, Comprising:
The photosensitive resin composition in which the structural unit represented by the said General formula (2) contains the structural unit which does not contain a crosslinkable group. It is the photosensitive resin composition of any one of Claims 1-3,
The photosensitive resin composition in which the said polymer further contains the structural unit represented by following Chemical formula (3).

It is the photosensitive resin composition of any one of Claims 1-3,
The photosensitive resin composition in which the said polymer further contains the structural unit represented by the following general formula (4).

In the general formula (4), R ^c represents a monovalent organic group containing a cyclic structure. It is the photosensitive resin composition of any one of Claims 1-5, Comprising:
The photosensitive resin composition in which the structural unit represented by the said General formula (1) contains the structural unit represented by following Chemical formula (1-1).

The photosensitive resin composition according to any one of claims 1 to 6, wherein
The photosensitive resin composition whose weight average molecular weight of the said polymer is 10000 or more. It is a photosensitive resin composition according to any one of claims 1 to 7, wherein
Furthermore, the photosensitive resin composition containing novolak resin. A process of forming a photosensitive resin film using the photosensitive resin composition according to any one of claims 1 to 8,
A pattern forming method including the steps of exposing the photosensitive resin film and developing the photosensitive resin film.   The manufacturing method of an electronic device containing the pattern formation method of Claim 9. A polymer comprising a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2).

In the general formula (1),
R represents a monovalent substituent,
m represents an integer of 1 to 3;
n represents an integer of 0 to 4;
However, m + n is 5 or less.
In the general formula (2),
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group other than a carboxyl group,
n represents an integer of 0 to 2; 12. A polymer according to claim 11, wherein
Polymers containing no structural unit having an oxetanyl group. A polymer according to claim 11 or 12,
The polymer in which the structural unit represented by the said General formula (2) contains the structural unit which does not contain a crosslinkable group. 14. A polymer according to any one of the claims 11-13, wherein
Furthermore, a polymer comprising a structural unit represented by the following chemical formula (3).

A polymer according to any one of the claims 11-14,
Furthermore, a polymer comprising a structural unit represented by the following general formula (4).

In the general formula (4), R ^c represents a monovalent organic group containing a cyclic structure. The polymer according to any one of claims 11 to 15, wherein
The polymer in which the structural unit represented by the said General formula (1) contains the structural unit represented by following Chemical formula (1-1).

17. A polymer according to any one of the claims 11-16,
Polymer having a weight average molecular weight of 10000 or more. A method of producing the polymer according to any one of claims 11 to 17, wherein
Charging a first solution containing at least a monomer represented by the following general formula (m2) and a polymerization initiator into a reaction vessel;
A start step of raising the temperature of the first solution to start a polymerization reaction;
Adding a second solution containing at least a monomer represented by the following general formula (m1) and not containing a monomer represented by the following general formula (m2) into the reaction vessel: production of a polymer Method.

In the general formula (m1),
R represents a monovalent substituent,
m represents an integer of 1 to 3;
n represents an integer of 0 to 4;
However, m + n is 5 or less.
In the general formula (m2),
R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group other than a carboxyl group,
n represents an integer of 0 to 2;