Resin composition, pattern forming method, method for manufacturing electronic device, and polymer

Abstract

To provide a resin composition capable of forming a high-resolution pattern by development processing using, for example, a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution.SOLUTION: The resin composition includes a polymer having a structural unit represented by general formula (NB) and a maleimide structural unit, and a solvent. When an intensity at a chemical shift of 11. 1H in a 30ppm NMR chart of the polymer is defined as I11. 30 and an intensity at a chemical shift of 11. 50ppm is defined as I11. 50, I11. 50 / I11. 30 is 1.08 or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a pattern forming method, a method for manufacturing an electronic device, and a polymer. [Background technology]

[0002] Various resin compositions are used in the manufacture of electronic devices. As electronic devices become smaller and more complex and the circuits in electronic devices become finer, improvements in resin compositions are also continuing (for example, Patent Documents 1 and 2).

[0003] Resist compositions are an important type of resin composition in the manufacture of electronic devices. A resin pattern can be formed on a substrate through a first step in which the resist composition is applied to a substrate to form a resin film, a second step in which the resin film is irradiated with actinic rays or radiation, and a third step in which the resin film formed after the second step is developed. By applying an etching gas to the substrate on which this resin pattern has been formed, only a portion of the substrate can be selectively etched. In other words, the resin pattern functions as an etching mask.

[0004] In the second step, development is often carried out using an alkaline developer, and therefore the resin composition and / or the polymer contained in the resin composition preferably have a suitable alkali solubility. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-131762 [Patent Document 2] International Publication No. 2016 / 049123 Summary of the Invention [Problem to be solved by the invention]

[0006] In pattern formation using resin compositions such as resist compositions, a 2.38% by mass aqueous solution of tetramethylammonium hydroxide (TMAH) has traditionally been used as the developer. To form fine resin patterns, both the resin composition and the developer should be improved and optimized. However, because changing the developer requires the introduction of new equipment, there is a need within the industry to continue using a 2.38% by mass aqueous solution of TMAH as the developer. Furthermore, with the progress of miniaturization of wiring in electronic devices, there is an increasing demand for forming high-resolution patterns using resin compositions such as resist compositions. Also,

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resin composition that can form a high-resolution pattern by development using, for example, a 2.38 mass % aqueous solution of tetramethylammonium hydroxide (TMAH). [Means for solving the problem]

[0008] The present inventors have completed the invention provided below and solved the above problems.

[0009] 1. A polymer having a structural unit represented by the following general formula (NB) and a structural unit represented by the following formula (MI-1), A solvent, A resin composition comprising: The NMR spectra of the polymer measured using dimethyl sulfoxide-d6 as the solvent were 1 The intensity at the chemical shift of 11.30 ppm in the H-NMR chart is I 11.30 , the intensity at the chemical shift of 11.50 ppm is I 11.50 When I 11.50 / I 11.30 A resin composition having a value of 1.08 or less. [ka] In the general formula (NB), R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms, provided that R 1 , R 2 , R 3 and R 4 at least one of the groups is a group having an alkali-soluble group, a1 is 0, 1 or 2. [ka] 2. 1. The resin composition according to claim 1, Above I 11.50 / I 11.30 A resin composition having a value of 0.50 or more. 3. 1. The resin composition according to 1. or 2., The resin composition, wherein the polymer further has a structural unit represented by the following general formula (MI-2): [ka] In the general formula (MI-2), X is a monovalent organic group containing a cyclic skeleton. 4. The resin composition according to any one of 1. to 3., A resin composition, wherein the group having an alkali-soluble group in said general formula (NB) is a group having a -C(CF3)2OH group. 5. The resin composition according to any one of 1. to 4., A resin composition, wherein the group having an alkali-soluble group in the general formula (NB) is a group represented by the following general formula (fa): -LC(CF3)2OH (fa) In the general formula (fa), L is a single bond or an alkylene group having 1 to 6 carbon atoms. 6. 3. The resin composition according to claim 1, A resin composition, wherein X in the general formula (MI-2) contains a cycloaliphatic group. 7. The resin composition according to any one of 1. to 6., the content of the structural unit represented by general formula (NB) in the polymer is 1 to 50 mol %, A resin composition, wherein the content of the structural unit represented by the formula (MI-1) in the polymer is 1 to 50 mol %. 8. The resin composition according to any one of 1. to 7., A resin composition whose solubility in an alkaline developer changes upon exposure to actinic rays or radiation. 9. a first step of applying the resin composition according to item 8. onto a substrate to form a resin film; a second step of irradiating the resin film with actinic rays or radiation; a third step of developing the resin film after the second step to obtain a substrate on which a resin pattern is formed; A pattern forming method comprising: 10. A fourth step of etching the substrate on which the resin pattern is formed, obtained by the pattern forming method described in 9.; a removing step of removing the resin pattern remaining on the substrate after the fourth step; A method for manufacturing an electronic device, comprising: 11. A polymer having a structural unit represented by the following general formula (NB) and a structural unit represented by the following formula (MI-1): NMR measurements were performed using dimethyl sulfoxide-d6 as the solvent. 1 The intensity at the chemical shift of 11.30 ppm in the H-NMR chart is I 11.30 , the intensity at the chemical shift of 11.50 ppm is I 11.50 When I 11.50 / I 11.30 A polymer having a value of 1.08 or less. [ka] In the general formula (NB), R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms, provided that R 1 , R 2 , R 3 and R 4 at least one of the groups is a group having an alkali-soluble group, a1 is 0, 1 or 2. [ka] 12. 11. The polymer according to claim 11, Above I 11.50 / I 11.30 Polymers with a value of 0.50 or greater. 13. 11. or 12. The polymer according to Further, the polymer has a structural unit represented by the following general formula (MI-2): [ka] In the general formula (MI-2), X is a monovalent organic group containing a cyclic skeleton. 14. 11. The polymer according to any one of 11. to 13., A polymer, wherein the group having an alkali-soluble group in the general formula (NB) is a group having a -C(CF3)2OH group. 15. 11. The polymer according to any one of 11. to 14., A polymer, wherein the group having an alkali-soluble group in the general formula (NB) is a group represented by the following general formula (fa): -LC(CF3)2OH (fa) In the general formula (fa), L is a single bond or an alkylene group having 1 to 6 carbon atoms. 16. The polymer according to any one of 11 to 15, A polymer in which X in the general formula (MI-2) contains a cycloaliphatic group. 17. 16. The polymer according to any one of 11. to 16., the content of the structural unit represented by the general formula (NB) is 1 to 50 mol %, A polymer in which the content of the structural unit represented by the formula (MI-1) is 1 to 50 mol %. [Effects of the Invention]

[0010] According to the present invention, there is provided a resin composition that can form a high-resolution pattern by development using, for example, a 2.38 mass % aqueous solution of tetramethylammonium hydroxide (TMAH). DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail.

[0012] In this specification, unless otherwise specified, the expression "X to Y" in the description of a numerical range means at least X and at most Y. For example, "1 to 5% by mass" means "at least 1% by mass and at most 5% by mass."

[0013] In the description of groups (atomic groups) in this specification, when a notation does not specify whether the group is substituted or unsubstituted, it encompasses both groups having no substituents and groups having a substituent. For example, the term "alkyl group" encompasses not only alkyl groups having no substituents (unsubstituted alkyl groups) but also alkyl groups having a substituent (substituted alkyl groups). In this specification, the term "(meth)acrylic" represents a concept that encompasses both acrylic and methacrylic. The same applies to similar terms such as "(meth)acrylate." Unless otherwise specified, the term "organic group" as used herein refers to an atomic group formed by removing one or more hydrogen atoms from an organic compound. For example, a "monovalent organic group" refers to an atomic group formed by removing one hydrogen atom from any organic compound. In this specification, the term "electronic device" is used to encompass elements, devices, final products, etc. to which electronic engineering technology is applied, such as semiconductor chips, semiconductor elements, printed wiring boards, electric circuit display devices, information and communication terminals, light-emitting diodes, physical batteries, and chemical batteries.

[0014] <Resin composition> The resin composition of the present embodiment is A polymer having a structural unit represented by the following general formula (NB) and a structural unit represented by the following formula (MI-1), A solvent, Includes. [ka] In the general formula (NB), R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms, provided that R 1 , R 2 , R 3 and R 4 at least one of the groups is a group having an alkali-soluble group, a1 is 0, 1 or 2. [ka]

[0015] The NMR spectra of the above polymers were measured using dimethyl sulfoxide-d6 as the solvent. 1 The intensity at the chemical shift of 11.30 ppm in the H-NMR chart is I 11.30 , the intensity at the chemical shift of 11.50 ppm is I 11.50 When I 11.50 / I 11.30 The value of is 1.08 or less, preferably 0.50 to 1.08, more preferably 0.60 to 1.08, still more preferably 0.60 to 1.00, and particularly preferably 0.60 to 0.90. Incidentally, the temperature for NMR measurements here is usually 25°C.

[0016] Based on past findings and the results of the inventor's preliminary investigation, 1 H-NMR charts can contain information about the "sequence" of specific structural units in a polymer. The electronic environment of the hydrogen atoms in a certain hydrogen-containing structural unit can change depending on whether the unit is randomly arranged in a polymer or arranged in a block. 1 It may appear on the H-NMR chart.

[0017] The H in the NH bond of the structural unit represented by the formula (MI-1) is easily dissociated, which contributes to increasing the alkali solubility of the polymer. 1 For H, dimethyl sulfoxide-d6 was used as the NMR solvent. 1 The chemical shift value in H-NMR measurement is usually within the range of 11 to 12 ppm. The chemical shift can change depending on whether the structural units represented by formula (MI-1) are arranged randomly in the polymer or in a block-like arrangement. Also, depending on the arrangement of the structural units represented by formula (MI-1) in the polymer, the obtained 1 In some cases, multiple peaks may be present between 11 and 12 ppm in the H-NMR chart. 1 In some cases, the peak can be recognized at a glance in the H-NMR chart, while in other cases, it is observed as a single broad peak at first glance, and it can only be recognized as multiple peaks after waveform separation.

[0018] As a result of various insights and trial and error by the inventors, the following polymers were measured using dimethyl sulfoxide-d6 as an NMR solvent: 1 Intensity I at chemical shift 11.30 ppm in the H-NMR chart 11.30 and the intensity I at a chemical shift of 11.50 ppm 11.50The present inventors have found that the ratio of I appears to correlate with the resolution in development processing using a 2.38% by mass aqueous TMAH solution. Based on this finding, the present inventors have conducted further research and found that I 11.50 / I 11.30 A resin composition containing a polymer having a value of 1.08 or less was newly prepared. It was confirmed that this resin composition had good resolution when developed using, for example, a 2.38% by mass aqueous solution of TMAH.

[0019] It is a guess, but I 11.50 / I 11.30 In polymers with a value of 1.08 or less, the structural units represented by formula (MI-1) containing alkali-soluble groups are thought to be present at fairly regular intervals in the polymer chain without being concentrated locally. This is thought to result in the developer penetrating the resin film and dissolving the polymer in the developer proceeding uniformly throughout, resulting in good resolution being obtained by development using a 2.38% by mass TMAH aqueous solution.

[0020] A polymer having a structural unit represented by general formula (NB) and a structural unit represented by formula (MI-1), and 11.50 / I 11.30 Polymers with a value of 1.08 or less can be obtained by using appropriate raw materials and adopting appropriate manufacturing conditions. Briefly, it is preferable to use a method in which a highly reactive maleimide structure-containing monomer is added later (addition) to the polymerization reaction system at a constant rate using a pump. Furthermore, it is more preferable to stop the polymerization reaction while some of the monomer remains unreacted, rather than consuming all of the monomer. The details of polymer manufacturing methods are described later. If the proper polymer manufacturing method is not adopted, I 11.50 / I 11.30 It may not be possible to produce polymers with a value of 1.08 or less.

[0021] The resin composition of this embodiment will be further described.

[0022] (polymer) The polymer has at least a structural unit represented by the following general formula (NB) and a structural unit represented by the following formula (MI-1).

[0023] [ka]

[0024] [ka]

[0025] In the general formula (NB), R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms, provided that R 1 , R 2 , R 3 and R 4 at least one of the groups is a group having an alkali-soluble group, a1 is 0, 1 or 2.

[0026] In general formula (NB), R 1 , R 2 , R 3 and R 4 Examples of the organic group having 1 to 30 carbon atoms include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, an alkaryl group, a cycloalkyl group, an alkoxy group, a heterocyclic group, and a carboxyl group.

[0027] Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a neopentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group. Examples of the alkenyl group include an allyl group, a pentenyl group, a vinyl group, etc. Examples of the alkynyl group include an ethynyl group, etc. Examples of the alkylidene group include a methylidene group and an ethylidene group. Examples of the aryl group include a tolyl group, a xylyl group, a phenyl group, a naphthyl group, and an anthracenyl group. Examples of the aralkyl group include a benzyl group and a phenethyl group. Examples of the alkaryl group include a tolyl group and a xylyl group. Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, an isobutoxy group, a tert-butoxy group, an n-pentyloxy group, a neopentyloxy group, an n-hexyloxy group, etc. Examples of the heterocyclic group include an epoxy group, an oxetanyl group, etc.

[0028] Examples of the group having an alkali-soluble group in general formula (NB) include a carboxy group, a phenolic hydroxyl group, and a group having a -C(CF3)2OH group. Preferably, the group having an alkali-soluble group in general formula (NB) is a group having a -C(CF3)2OH group. More preferably, the group having an alkali-soluble group in general formula (NB) is a group represented by the following general formula (fa). -LC(CF3)2OH (fa) In the general formula (fa), L is a single bond or an alkylene group having 1 to 6 carbon atoms.

[0029] Considering the reaction with compounds containing two or more diazirine structures in one molecule (the mechanism of insertion of carbene into a C-H bond), R 1 , R 2 , R 3 and R 4 It is thought that selecting a material containing a large amount of CH as a catalyst will lead to further improvement in sensitivity. 1 , R 2, R 3 and R 4 The organic group in R is preferably a linear alkyl group having 3 to 30 carbon atoms. Taking into account the balance of other properties, 1 , R 2 , R 3 and R 4 The organic group is preferably a linear alkyl group having 4 to 20 carbon atoms, more preferably a linear alkyl group having 4 to 10 carbon atoms. On the other hand, in terms of improving solubility in alkaline developers, R 1 , R 2 , R 3 and R 4 It is preferred that 1 to 3 of these are hydrogen atoms and are not hydrophobic atomic groups such as alkyl groups.

[0030] The polymer preferably further has a structural unit represented by the following general formula (MI-2). [ka]

[0031] In the general formula (MI-2), X is a monovalent organic group containing a cyclic skeleton. The cyclic skeleton contained in X may be an aromatic group such as a benzene ring, or may be a cyclic aliphatic group. In terms of the balance of various properties, X preferably contains a cyclic aliphatic group. The cyclic aliphatic group is preferably saturated and does not contain a carbon-carbon double bond. More specifically, X is preferably a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a norbornyl group, an adamantyl group, or the like. X may or may not have a substituent, but from the viewpoint of appropriately controlling solubility, it is preferable that X has no substituent.

[0032] The polymer may or may not have structural units other than the above-listed structural units. Examples of structural units other than the above-listed structural units include a structural unit in which the maleimide structure in the structural unit represented by general formula (MI-1) is ring-opened, a structural unit in which the maleimide structure in the structural unit represented by general formula (MI-2) is ring-opened, and a structural unit derived from maleic anhydride or a derivative thereof.

[0033] As a structural unit other than the above-listed structural units, specifically, in the general formula (NB), R 1 , R 2 , R 3 and R 4 are all hydrogen atoms or organic groups having 1 to 30 carbon atoms, and are not groups having a -C(CF3)2OH group. 1 , R 2 , R 3 and R 4 Examples of structural units include those in which at least one of the groups is an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group, and the remaining groups are hydrogen atoms. The alkyl group here may be linear or branched. The alkyl group has, for example, 1 to 20 carbon atoms, preferably 1 to 10, and more preferably 3 to 8 carbon atoms. The cycloalkyl group has, for example, 5 to 8 carbon atoms. The aryl group has, for example, 6 to 20 carbon atoms, and more preferably 6 to 12 carbon atoms. The aralkyl group has, for example, 7 to 13 carbon atoms. This structural unit has the function of making the polymer appropriately hydrophobic, thereby adjusting the solubility in an alkaline developer.

[0034] In consideration of application to a resist composition, the polymer preferably does not contain an epoxy group-containing structural unit, or if it does contain one, the proportion of such a structural unit is preferably 5 mol % or less, more preferably 3 mol % or less, and even more preferably 1 mol % or less, of the total structural units of the polymer. Similarly, the polymer does not contain any oxetanyl group-containing structural units, or if it does contain any, the proportion of such units in the total structural units of the polymer is preferably 5 mol % or less, more preferably 3 mol % or less, and even more preferably 1 mol % or less. Furthermore, the polymer does not contain any silicon atom-containing structural units, or if it does contain any silicon atom-containing structural units, the proportion of such units is preferably 5 mol % or less, more preferably 3 mol % or less, and even more preferably 1 mol % or less, of all structural units of the polymer.

[0035] The content of the structural unit represented by general formula (NB) in the polymer is preferably 1 to 50 mol %, more preferably 10 to 40 mol %, and even more preferably 20 to 35 mol %. The content of the structural unit represented by formula (MI-1) in the polymer is preferably 1 to 50 mol %, more preferably 10 to 40 mol %, and even more preferably 20 to 35 mol %. When the polymer has a structural unit represented by general formula (MI-2), the content in the polymer is preferably 10 to 55 mol %, more preferably 20 to 50 mol %, and even more preferably 30 to 50 mol %.

[0036] The resin composition of this embodiment may contain only one polymer, or may contain two or more polymers. When the resin composition of this embodiment contains two or more polymers, all of the polymers have a structural unit represented by general formula (NB) and a structural unit represented by general formula (MI-1), and 11.50 / I 11.30 The polymer may or may not have a value of 1.08 or less. However, from the viewpoint of reliably obtaining the effect, preferably 50% by mass or more, more preferably 75% by mass or more, and even more preferably 90% by mass or more of all polymers in the resin composition have a structural unit represented by general formula (NB) and a structural unit represented by general formula (MI-1), and 11.50 / I 11.30 The polymer has a value of 1.08 or less.

[0037] The weight-average molecular weight of the polymer may be appropriately adjusted in consideration of appropriate solubility in an alkaline developer, etc. The weight-average molecular weight of the polymer is, for example, 3,000 to 100,000, preferably 3,000 to 50,000, more preferably 3,000 to 12,000, and particularly preferably 3,000 to 6,000. From the standpoint of further reducing pattern roughness when used as a resist composition, the polydispersity index (PDI) of the polymer is preferably from 1.1 to 2.0, and more preferably from 1.1 to 1.6.

[0038] The proportion of the polymer in the non-volatile components (components other than the solvent) of the resin composition is preferably 60 to 90% by mass, and more preferably 70% to 90% by mass.

[0039] (Polymer synthesis and purification methods) Polymers can usually be synthesized (produced) by radical polymerization, i.e., by polymerizing a monomer (having a radically polymerizable carbon-carbon double bond) corresponding to the structural unit of each of the general formulae above in an appropriate organic solvent by the action of a radical initiator.

[0040] Although known techniques can be appropriately applied to synthesize polymers, in this embodiment, the "arrangement" of each structural unit in the polymer is particularly appropriately controlled to synthesize I. 11.50 / I 11.30 It is preferable to devise a polymerization method in order to synthesize a polymer having a value of 1.08 or less.

[0041] Specifically, a solution of a monomer corresponding to the structural unit represented by general formula (NB) dissolved in a solvent is placed in a reaction vessel. Then, while the reaction vessel is heated, a monomer corresponding to the structural unit of formula (MI-1) and a polymerization initiator are gradually added to the reaction vessel over time. Monomers corresponding to the structural unit of formula (MI-1) are thought to have high polymerization reactivity. Therefore, when a monomer corresponding to the structural unit of formula (MI-1) and a monomer corresponding to the structural unit represented by general formula (NB) are polymerized together, the monomer corresponding to the structural unit of formula (MI-1) is preferentially consumed, and the structural unit of formula (MI-1) is thought to be locally concentrated in the polymer. However, as described above, if the monomer corresponding to the structural unit of formula (MI-1) is gradually added to a reaction vessel that has already been charged with the monomer corresponding to the structural unit represented by general formula (NB), it is thought that the structural unit of formula (MI-1) can be prevented from being locally concentrated in the polymer.

[0042] Furthermore, according to the knowledge of the present inventors, in the above-mentioned polymerization reaction, instead of reacting substantially all of the monomer, the polymerization reaction is completed with a small amount of unreacted monomer remaining, thereby further improving the I 11.50 / I 11.30 This method tends to facilitate the synthesis of polymers having a value of 1.08 or less. This is because, even if the monomer corresponding to the structural unit of formula (MI-1) is added later as described above, the concentration of the monomer corresponding to the structural unit represented by general formula (NB) has already decreased in the later stage of the polymerization reaction, and the monomer corresponding to the structural unit of formula (MI-1) may be preferentially consumed. As will be shown in the examples below, polymers obtained by completing the polymerization reaction while leaving a small amount of unreacted monomer exhibit better performance.

[0043] Regarding the purification method of the synthesized polymer (method of reducing impurities), publicly known information can be referred to as appropriate. In particular, when the resin composition of the present embodiment is used as a resist composition, it is preferable to reduce impurities as much as possible.

[0044] (solvent) The resin composition of the present embodiment contains a solvent. In other words, the resin composition of the present embodiment is preferably a composition in which at least the polymer is dissolved or dispersed in a solvent. The solvent typically includes an organic solvent, specifically, a ketone-based solvent, an ester-based solvent, an ether-based solvent, an alcohol-based solvent, a lactone-based solvent, a carbonate-based solvent, or the like.

[0045] Preferred solvents include propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), ethyl lactate, methyl isobutyl carbinol (MIBC), gamma butyrolactone (GBL), N-methylpyrrolidone (NMP), methyl-n-amyl ketone (MAK), diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, cyclohexanone, and mixtures thereof.

[0046] The solvent may be a single solvent or a mixed solvent. The amount of the solvent used is adjusted appropriately so that the concentration of non-volatile components in the composition is usually about 1 to 20% by mass, preferably about 1 to 15% by mass.

[0047] (Component for making the resin composition photosensitive) For example, the resin composition preferably contains a compound (acid generator) that generates an acid under the action of actinic rays or radiation, and a compound (crosslinking agent) that undergoes a crosslinking reaction under the action of the acid. A negative resin pattern can be formed by irradiating a resin film formed from a resin composition containing the acid generator and the crosslinking agent with actinic rays or radiation, and then developing the resin film.

[0048] As another example, the resin composition preferably contains a compound containing two or more diazirine structures in one molecule (hereinafter referred to as a diazirine compound). A resin film formed from a resin composition containing a diazirine compound is irradiated with actinic rays or radiation, and then the resin film is developed, thereby forming a negative resin pattern. When a diazirine compound is irradiated with actinic rays or radiation, N2 is eliminated from the diazirine structure, generating a carbene (a bicoordinated carbon atom with only six valence electrons and no charge). The generated carbene reacts with a polymer to form a bond. In particular, because the generated carbene is inserted into a C—H bond, the polymer that reacts with the carbene does not need to have any special functional groups. Therefore, the diazirine compound can form bonds with a variety of polymers. In this embodiment, a diazirine compound containing two or more diazirine structures per molecule is used, and the polymer is "crosslinked" by the diazirine compound. As a result, the portions of the resin film irradiated with actinic rays or radiation become insoluble or poorly soluble in the developer. Therefore, a pattern can be formed by selectively irradiating a resin film with actinic rays or radiation and then performing a development process.

[0049] Diazirine compounds will be described below.

[0050] The number of diazirine structures in one molecule of the diazirine compound is usually 2 to 6, preferably 2 to 4, and more preferably 2 to 3.

[0051] The diazirine compound preferably contains a structure represented by the following general formula (b): Specifically, the diazirine compound preferably contains two or more structures represented by the following general formula (b) in one molecule.

[0052] [ka]

[0053] In general formula (b), R x represents a monovalent substituent, When a plurality of R's are present, each R's independently represents a monovalent substituent. n represents an integer of 0 to 4, * denotes a bond to another chemical structure.

[0054] The two or more structures represented by general formula (b) present in one molecule of the diazirine compound may be the same or different structures. An example of the latter is compound (B) having, in one molecule, a structure represented by general formula (b) where n is 0 and a structure represented by general formula (b) where n is 1.

[0055] R x From the viewpoint of increasing the sensitivity of the photosensitive resin composition, the monovalent substituent of R is preferably an electron-withdrawing group. The electron-withdrawing group may be any group generally recognized as an electron-withdrawing group in the field of organic chemistry. x Specific examples of R include fluorinated alkyl groups, chlorinated alkyl groups, -NO2, -CN, -CHO, -COR, -COOR, -COOH, -SO2R, and -SO3H. Here, R is a monovalent organic group, and specific examples include the same organic groups having 1 to 30 carbon atoms as in general formula (NB). From the viewpoints of ease of synthesis, cost, and sensitivity to electron beams or EUV light, it is preferable to use an electron-withdrawing group, R x As the alkyl group, a fluorinated alkyl group is preferable, a perfluoroalkyl group is more preferable, and a trifluoromethyl group is even more preferable. From the viewpoint of prioritizing the storage stability of the photosensitive resin composition, for example, R x The monovalent substituent of R does not have to be an electron-withdrawing group. x may be a hydrogen atom. x may be an organic group (such as an alkyl group, an alicyclic group, or an aromatic group) that is not substituted with fluorine. In consideration of availability, ease of synthesis, and appropriate reactivity, R x is preferably a hydrogen atom or an alkyl group, more preferably a hydrogen atom or a methyl group, and even more preferably a hydrogen atom.

[0056] Specific examples of R include R in general formula (NB) 1 , R 2 , R 3 and R 4 Examples of the organic group include an organic group having 1 to 30 carbon atoms, a halogen atom, and a hydroxy group. From the viewpoint of ease of synthesis / availability of diazirine compounds, n is preferably 0.

[0057] The diazirine compound more preferably contains a structure represented by the following general formula (b1):

[0058] [ka]

[0059] In general formula (b1), R EWG The definitions of , R, n and * are the same as those in general formula (b). R EWG The preferred embodiments of R and n are the same as those listed in the general formula (b).

[0060] In the structure represented by general formula (b1), the electron-donating property of the oxygen atom increases the reactivity of the diazirine structure portion, and carbene tends to be more easily generated by irradiation with an electron beam or EUV light. In other words, the use of a diazirine compound containing a structure represented by general formula (b1) tends to further increase sensitivity.

[0061] The two or more structures represented by general formula (b1) present in one molecule of the diazirine compound may be the same or different structures. An example of the latter is compound (B) having, in one molecule, a structure represented by general formula (b1) where n is 0 and a structure represented by general formula (b1) where n is 1.

[0062] Specifically, the diazirine compound can have a structure represented by the following general formula (BB).

[0063] [ka]

[0064] In general formula (BB), A represents a group represented by the above general formula (b) or general formula (b1), k is an integer equal to or greater than 2, L is a k-valent linking group.

[0065] In general formula (BB), there can be a plurality of A's. The plurality of A's may have the same structure or different structures.

[0066] From the viewpoints of ease of synthesis and availability and the balance of various performances, k is preferably 2 to 6, more preferably 2 to 4, and even more preferably 2 to 3.

[0067] When L is a divalent linking group, L can specifically be a linear or branched alkylene group, a group in which two hydrogen atoms have been removed from an alicyclic group, an arylene group, -O-, -CO-, -COO-, -OCO-, -NH-, -NR- (R is a monovalent organic group), -S-, -SO2-, a group in which two or more of these groups are linked together, etc. L is preferably a linear or branched alkylene group, an arylene group, -O-, or a group in which two or more of these groups are linked together. When L is a trivalent or higher valent linking group, L can specifically be a group in which one or more hydrogen atoms have been further removed from the above divalent linking group. L is typically a k-valent organic group.

[0068] From the viewpoints of ease of synthesis of the diazirine compound and appropriate curability, it is preferable that the "length" of the L portion is appropriate. Here, the "length" of the L moiety is defined as the number of atoms on the shortest path from the atom in L to which a certain A is directly covalently bonded as the starting point, tracing only the covalent bonds in L, to the atom to which another A is directly covalently bonded (end point). However, when A in the L moiety is a group represented by general formula (b1), the "length" of the L moiety is calculated by including the oxygen atom connected to the benzene ring in general formula (b1). In other words, when A in the L moiety is a group represented by general formula (b1), the oxygen atom in general formula (b1) is used as the starting point or end point. Furthermore, when the diazirine compound has 3 or more As, the shortest definable length is used as the "length." For example, if a diazirine compound has three As, A1, A2, and A3, and the "length" from A1 to A2 is 10 and the "length" from A1 to A2 is 12, then the "length" of the L moiety in this compound (B) is 10. For example, the "length" of the L portion in BONDLYNX BLD-201 used in the examples below is 10.

[0069] In terms of ease of synthesis of the diazirine compound, appropriate curability, and the like, the "length" of the L moiety is, for example, 1 to 20, preferably 1 to 16. As another example, the "length" of the L moiety is preferably 6 to 20, more preferably 8 to 20. When the L moiety is "appropriately long," the diazirine compound (or carbene generated from the diazirine compound) in the film formed from the composition becomes more likely to react with the polymer, which may further improve sensitivity. On the other hand, when the L moiety is "not too long," contact between the diazirine compound (or carbene generated from the diazirine compound) and the polymer is suppressed, which may improve the stability of the composition over time.

[0070] The temporal stability of the composition tends to be improved by L being electron-withdrawing or by L being substituted with an electron-withdrawing group. For example, the temporal stability of the composition tends to be improved by using a diazirine compound in which L has a fluorine atom in general formula (BB), a diazirine compound in which L is an organic group substituted with a fluorine atom in general formula (BB), or a diazirine compound in which L is a fluorinated alkylene group in general formula (BB). It is believed that L being electron-withdrawing or being substituted with an electron-withdrawing group makes the generation of carbene by N2 elimination slightly thermodynamically unfavorable, i.e., carbene generation is slightly more difficult. This is thought to suppress unintended decomposition of the diazirine compound and improve sensitivity. Although sensitivity may be slightly reduced, when emphasis is placed on the stability of the composition over time, it is preferable to select a diazirine compound in which L is electron-withdrawing or in which L is substituted with an electron-withdrawing group.

[0071] The molecular weight of the diazirine compound is typically 100 to 2000, preferably 100 to 1000. The diazirine compound is typically a low molecular weight compound and is not a polymer.

[0072] Diazirine compounds can be purchased, for example, from XlynX Materials Inc., based in Canada. Further, specific examples of the diazirine compound include compounds having a diazirine structure exemplified in Patent Document 2. Furthermore, diazirine compounds having the following structure are also preferably used.

[0073] [ka]

[0074] When a diazirine compound is used, only one diazirine compound may be used, or two or more diazirine compounds may be used in combination. From the viewpoint of the balance of various performances, when a diazirine compound is used, the amount thereof is usually 5 to 50 parts by mass, preferably 8 to 40 parts by mass, and more preferably 10 to 30 parts by mass, per 100 parts by mass of the polymer.

[0075] (Other optional ingredients) The resin composition of the present embodiment may contain optional components other than those described above. Examples of the optional components include a developing aid, a plasticizer, an antioxidant, a leveling agent, and a surfactant.

[0076] In particular, from the viewpoint of obtaining a resin film with good in-plane uniformity by coating, it is preferable to use one or more surfactants. The type of surfactant is not particularly limited. Any surfactant that can be appropriately dissolved or dispersed in a solvent can be used. Examples of surfactants include those described in paragraph

[0276] of U.S. Patent Application Publication No. 2008 / 0248425. Other examples include the "F-Top" series from Shin-Akita Chemical Industry Co., Ltd., the "Fluorad" series from 3M, the "Megafac" series from DIC Corporation, and the "Surflon" series from AGC Sei Chemical Co., Ltd. As the surfactant, a fluorine-based surfactant or a silicon-based surfactant can be preferably used, and a nonionic surfactant containing a fluorine atom is particularly preferably used. When a surfactant is used, the amount used can be, for example, 0.01 to 3 parts by mass, specifically 0.1 to 1 part by mass, per 100 parts by mass of the polymer.

[0077] <Pattern Forming Method and Electronic Device Manufacturing Method> A pattern can be formed by using a resin composition whose solubility in an alkaline developer changes due to the action of actinic rays or radiation, that is, a photosensitive resin composition, through the following steps. The first step is to apply a resin composition to a substrate to form a resin film. The second step is to irradiate the resin film formed in the first step with actinic rays or radiation. The third step is to develop the resin film after the second step to obtain a substrate with a resin pattern formed on it. This allows a resin pattern to be formed on the substrate.

[0078] Also, A fourth step of etching the substrate on which the resin pattern is formed, obtained as described above; A removal process for removing the resin pattern remaining on the substrate after the fourth process; By carrying out the above steps, an electronic device can be manufactured.

[0079] These steps will be specifically described below.

[0080] (First step: forming a resin film) The substrate on which the resin film is formed is not particularly limited, and examples thereof include a glass substrate, a silicon wafer, a ceramic substrate, an aluminum substrate, a SiC wafer, a GaN wafer, a copper substrate, and a copper-plated substrate. The substrate may be an unprocessed substrate, or may be a substrate on which electrodes or elements are formed. An anti-reflection film may be provided on the substrate in advance. The anti-reflection film may be either an inorganic film type made of titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, amorphous silicon, or an organic film type made of a light absorber and a polymer material. Alternatively, commercially available organic anti-reflection films, such as the DUV30 series and DUV-40 series manufactured by Brewer Science, or the AR-2, AR-3, and AR-5 manufactured by Shipley, may be used.

[0081] The method for forming the resin film is not particularly limited. In the field of electronic device manufacturing, spin coating using a spinner is common, but other methods may also be used. For example, spray coating using a spray coater, dipping, printing, roll coating, inkjet method, etc. may also be used.

[0082] The composition coated on the substrate is typically dried by a heat treatment. The heating temperature is usually 50 to 140°C, preferably 60 to 120°C. An appropriate drying temperature can be set from the viewpoints of rapid and sufficient drying of the solvent and suppressing the generation of carbene from the diazirine compound. The heating time varies depending on the heating device, but when a hot plate is used, it is usually 30 to 300 seconds, preferably about 60 to 180 seconds, and when a hot air oven is used, it is usually 5 to 60 minutes, preferably about 10 to 30 minutes.

[0083] The thickness (dry thickness) of the resin film is not particularly limited and may be adjusted appropriately depending on the size and aspect ratio of the pattern to be finally obtained. The thickness can be adjusted by adjusting the concentration of nonvolatile components in the composition or by changing the application method. The thickness is, for example, 10 to 1000 nm, specifically 20 to 500 nm.

[0084] (Second step: irradiation with actinic rays or radiation) The exposure step is usually carried out by irradiating the resin film with actinic rays or radiation. Preferred examples of actinic rays or radiation include far ultraviolet rays, extreme ultraviolet rays (EUV light), electron beams, etc. Extreme ultraviolet rays (EUV light) or electron beams are particularly preferred for forming fine patterns. When irradiating with electron beams as actinic rays or radiation, the irradiation dose is, for example, 10 to 1000 μC / cm 2 , specifically 20 to 500 μC / cm 2 The acceleration voltage of the electron beam can be set to, for example, 10 to 200 keV, specifically 30 to 150 keV. When irradiating with far ultraviolet or EUV light, the irradiation dose is, for example, 0.1 to 500 mJ / cm 2 , specifically 1 to 250 mJ / cm 2 It can be said that:

[0085] When irradiating a resin film with deep ultraviolet or EUV light to "pattern" the film, the deep ultraviolet or EUV light is usually irradiated through a photomask.

[0086] The alkali solubility of the resin composition of this embodiment is appropriately adjusted, and therefore the resin composition of this embodiment is preferably used for forming fine patterns using electron beams or EUV light.

[0087] If necessary, after irradiation with actinic rays or radiation and before the third step (development), the resin film may be heated (post-exposure bake). The temperature is, for example, 70 to 150° C., preferably 70 to 120° C. The time is usually 30 to 300 seconds, preferably 50 to 180 seconds, when using a hot plate, for example.

[0088] Post-exposure baking is usually carried out in chemically amplified compositions to promote a chain reaction caused by the action of an acid generated by irradiation with actinic rays or radiation. On the other hand, the resin composition of this embodiment is not necessarily a chemically amplified type. Specifically, the resin composition containing the diazirine compound described above is not necessarily a chemically amplified type. Therefore, in principle, patterning is possible without post-exposure baking. However, post-exposure baking may be effective in some cases to promote decomposition of the diazirine compound and / or promote bond formation between the polymer and the diazirine compound.

[0089] (Third step: development) A pattern can be obtained by developing a resin film irradiated with actinic rays or radiation. Typically, development is carried out using a developer by a method such as immersion, puddling, or rotary spraying. Development usually dissolves and removes the unexposed areas of the photosensitive resin film, resulting in a negative pattern.

[0090] As the developer, an alkaline aqueous solution is usually used, and specific examples of the alkaline aqueous solution include (i) aqueous inorganic alkaline solutions such as sodium hydroxide, sodium carbonate, sodium silicate, and ammonia, (ii) aqueous organic amine solutions such as ethylamine, diethylamine, triethylamine, and triethanolamine, and (iii) aqueous solutions of quaternary ammonium salts such as tetramethylammonium hydroxide and tetrabutylammonium hydroxide. As the developer, an aqueous solution of tetramethylammonium hydroxide is particularly preferred. The concentration of tetramethylammonium hydroxide is preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass, and particularly preferably 2.38% by mass.

[0091] Furthermore, as the developer, a developer containing an organic solvent, specifically a developer mainly composed of an organic solvent (the organic solvent accounts for 50% by mass or more of the developer), can also be used. As the developer containing an organic solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, an amide-based solvent, an ether-based solvent, a hydrocarbon-based solvent, etc. can be used. For more specific information about developers containing organic solvents, the description in paragraphs 0299 ​​to 0305 of Patent Document 1 can be referred to.

[0092] By performing the third step, a resin pattern can be obtained on the substrate. After development, it is preferable to wash the resin pattern and the substrate with a rinse liquid. Ultrapure water or alcohol is suitable as the rinse liquid.

[0093] (Fourth step: etching) The substrate on which the resin pattern obtained by the first to third steps is formed can be processed by etching it. Specifically, by applying an etching gas to the substrate on which the resin pattern is formed, a pattern can be formed in the portion of the substrate on which the resin pattern is not formed. In other words, the resin pattern functions as a "resist pattern" that prevents the substrate from being processed during etching. The etching may be wet etching, but dry etching is usually used in terms of ease of fine processing. The specific etching conditions and usable etching gases can be appropriately changed and optimized depending on the structure and specifications of the electronic device to be manufactured.

[0094] As described above, the pattern formed using the resin composition of this embodiment functions as a resist pattern during etching. In other words, the resin composition of this embodiment is preferably "for forming a resist pattern during an etching process." In other words, the resin composition of this embodiment is preferably not used to form a permanent film (a film that remains in the final electronic device) such as an insulating film.

[0095] (Removal process) The resin pattern remaining after the fourth step (etching) is usually removed with a resist remover. Residues generated by etching can be removed with an etching residue remover. As the resist stripping liquid and etching residue removing liquid, known liquids can be used appropriately.

[0096] (Other processes) In manufacturing the electronic device, various other steps may be performed, such as an ion implantation step, a bump electrode formation step, a rewiring formation step, and the like.

[0097] <Polymer> Up to this point, the description has been centered on the embodiment of the "resin composition" containing a polymer having a specific structural unit and a solvent. On the other hand, the polymers described in the section "Resin Composition" are useful because they have alkali solubility and other desirable properties. In other words, the polymers described in the section "Resin Composition" can be used in a variety of applications by themselves, and can be used for various purposes other than photosensitive resin compositions. Specific embodiments of the polymer have already been explained in the section on [Polymer] in <Resin Composition>, so further explanation will be omitted.

[0098] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations may be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and modifications and improvements within the scope of achieving the object of the present invention are included in the present invention. [Example]

[0099] The embodiments of the present invention will be described in detail based on Examples and Comparative Examples. However, it should be noted that the present invention is not limited to the Examples.

[0100] <Ingredient preparation> The following monomers were prepared:

[0101] [ka]

[0102] Furthermore, as a polymerization initiator, polymerization initiator VR-110 manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. was prepared.

[0103] <Synthesis Examples 1-1 and 1-2: Polymer Synthesis> (1) The following solutions A1 and B1 were prepared. Solution A1: 30% by mass HFANB anisole solution (Prepared by dissolving 62.7 g, 228 mmol of HFANB in ​​anisole) Solution B1: 30% by mass CyMI / H-MI + VR-110 (initiator; 50 / 1 Mon / In) in anisole (Prepared by dissolving 61.5 g, 343 mmol of CyMI, 22.2 g, 229 mmol of H-MI, and 4.06 g, 16.0 mmol of VR-110 in anisole)

[0104] (2) In a flask purged with nitrogen, Solution A1 was heated to 150°C. Then, while maintaining the temperature in the flask at 150°C, Solution B1 was added to the flask using a syringe pump at a rate of 0.46% by mass / min. In other words, when the total amount of Solution B1 prepared in (1) is taken as 100, 0.46% was added to the flask per minute.

[0105] In Synthesis Example 1-1, the addition of Solution B1 to the flask was stopped when 65% of Solution B1 had been added to the flask, and the reaction solution in the flask was allowed to cool naturally to room temperature. In Synthesis Example 1-2, all of Solution B1 was added to the flask at the above rate. After the addition was completed, the reaction solution in the flask was allowed to cool naturally to room temperature.

[0106] (3) The cooled reaction solution was added dropwise to heptane. This resulted in a white to yellow precipitate. The resulting precipitate was filtered, washed with heptane, and then dried overnight in a vacuum dryer at 80°C. This resulted in a white to yellow polymer powder.

[0107] <Synthesis Examples 2-1 and 2-2: Polymer Synthesis> (1) The following solutions A2 and B2 were prepared. Solution A2: 30% by mass HFANB anisole solution (Prepared by dissolving 33.2 g, 121 mmol of HFANB in ​​anisole) Solution B2: 30% by mass CyMI / H-MI + VR-110 (initiator; 50 / 1 Mon / In) in anisole (Prepared by dissolving 28.2g, 158mmol of CyMI, 11.8g, 121mmol of H-MI, and 2.03g, 8.0mmol of VR-110 in anisole)

[0108] (2) In a flask purged with nitrogen, Solution A2 was heated to 150°C. Then, while maintaining the temperature in the flask at 150°C, Solution B2 was added to the flask using a syringe pump at a rate of 0.46% by mass / min. In other words, when the total amount of Solution B2 prepared in (1) is taken as 100, 0.46% was added to the flask per minute.

[0109] In Synthesis Example 2-1, the addition of Solution B2 to the flask was stopped when 65% of Solution B2 had been added to the flask, and the reaction solution in the flask was allowed to cool naturally to room temperature. In Synthesis Example 2-2, all of Solution B2 was added to the flask at the above rate. After the addition was completed, the reaction solution in the flask was allowed to cool naturally to room temperature.

[0110] (3) The cooled reaction solution was added dropwise to heptane. This resulted in a white to yellow precipitate. The resulting precipitate was filtered, washed with heptane, and then dried overnight in a vacuum dryer at 80°C. This resulted in a white to yellow polymer powder.

[0111] <Synthesis Example 3-1: Polymer synthesis> (1) The following solutions A3 and B3 were prepared. Solution A3: 30% by mass HFANB anisole solution (Prepared by dissolving 32.3 g, 118 mmol of HFANB in ​​anisole) Solution B3: 30% by mass CyMI / H-MI + VR-110 (initiator; 50 / 1 Mon / In) in anisole (Prepared by dissolving 29.5g, 164mmol of CyMI, 11.4g, 118mmol of H-MI, and 2.03g, 8.0mmol of VR-110 in anisole)

[0112] (2) In a flask purged with nitrogen, Solution A3 was heated to 150°C. Then, while maintaining the temperature in the flask at 150°C, Solution B3 was added to the flask using a syringe pump at a rate of 0.46% by mass / min. In other words, when the total amount of Solution B3 prepared in (1) is taken as 100, 0.46% was added to the flask per minute.

[0113] In Synthesis Example 3-1, the addition of Solution B3 to the flask was stopped when 65% of Solution B3 had been added to the flask, and the reaction solution in the flask was allowed to cool naturally to room temperature.

[0114] (3) The cooled reaction solution was added dropwise to heptane. This resulted in a white to yellow precipitate. The resulting precipitate was filtered, washed with heptane, and then dried overnight in a vacuum dryer at 80°C. This resulted in a white to yellow polymer powder.

[0115] <Comparative Synthesis Example 1: Polymer Synthesis> 62.7 g, 228 mmol of HFANB, 61.5 g, 343 mmol of CyMI, 22.2 g, 229 mmol of H-MI, and 4.06 g, 16.0 mmol of VR-110 were dissolved in anisole to prepare a solution with a concentration of 30 mass %. This solution was placed in a flask, and after replacing the atmosphere with nitrogen, the solution was heated to 150° C. to allow the polymerization reaction to proceed. During the reaction, the concentration of the residual monomer was measured intermittently using a gas chromatograph. 90 minutes after the reaction solution reached 150°C, heating was stopped to stop the polymerization reaction. The reaction solution in the flask was then allowed to cool naturally to room temperature. The resulting polymer was purified and dried in the same manner as in Synthesis Example 1-1 and Synthesis Example 1-2 (3), thereby obtaining a white to yellow polymer powder.

[0116] <Comparative Synthesis Example 2: Polymer Synthesis> 33.2 g (121 mmol) of HFANB, 28.2 g (158 mmol) of CyMI, 11.8 g (121 mmol) of H-MI, and 2.03 g (8.0 mmol) of VR-110 were dissolved in anisole to prepare a 30% by mass solution. This solution was placed in a flask, purged with nitrogen, and heated to 150 °C to proceed with the polymerization reaction. During the reaction, the concentration of the remaining monomers was intermittently measured using a gas chromatograph. Then, 90 minutes after the reaction solution reached 150 °C, the heating was stopped to terminate the polymerization reaction. Thereafter, the reaction solution in the flask was naturally cooled to room temperature. Then, in the same manner as in (3) of Synthesis Example 1-1 and Synthesis Example 1-2, the obtained polymer was purified and dried. As a result, a white to yellow polymer powder was obtained.

[0117] <Monomer introduction ratio> In the synthesis examples, the monomer concentration in the reaction solution after the reaction was analyzed using a gas chromatograph. Then, assuming that all the consumed monomers were incorporated into the polymer, the monomer introduction ratio in each polymer was calculated.

[0118] <GPC measurement> The number average molecular weight Mn, weight average molecular weight Mw, and polydispersity PDI were determined by gel permeation chromatography (GPC) using polystyrene as a standard substance.

[0119] <Polymer's 1 1H-NMR measurement> The obtained polymer (30 mg) was dissolved in dimethyl sulfoxide-d6 (1 g), which is an NMR solvent, to obtain a 3% by mass measurement sample. This sample was placed in an NMR tube and set in an NMR apparatus (400 MHz) to obtain a 1H-NMR chart at 25 °C. 1 1H-NMR chart was obtained. The obtained 1 In the obtained 1H-NMR chart, the intensity I at a chemical shift of 11.30 ppm 11.30 and the intensity I at a chemical shift of 11.50 ppm 11.50 were read, and I11.50 / I 11.30 The value of I was calculated. 11.30 and I 11.50 The intensity was expressed as a relative value, with the larger value being set at 100.00. In addition, for some polymers, 1 The monomer introduction ratio was calculated based on the area ratio of each peak in the H-NMR chart. For reference, the peak assignments (regions where the area ratio was calculated by integration) are as follows: (i) 11.0 to 11.8 ppm: H in NH groups in H-MI (ii) 7.4-7.8 ppm: H in hydroxyl groups in HFANB (iii) 3.5 to 3.9 ppm: H bonded to the carbon atom bonded to the N atom in the cyclohexyl group in CyMI

[0120] <Measurement of alkaline dissolution rate> The synthesized polymer was dissolved in propylene glycol monomethyl ether acetate (PGMEA) to prepare a solution with a concentration of 10% by mass. Each of these solutions was spin-coated onto a silicon wafer, and the solvent was dried to obtain a resin film with a thickness T of approximately 300 nm. This resin film was immersed together with the silicon wafer in a 2.38 mass % aqueous solution of tetramethylammonium hydroxide at 25° C., and the time t until the film thickness became zero was measured. The dissolution rate was then calculated by calculating T / t.

[0121] The polymer information is summarized in the table below.

[0122] [Table 1]

[0123] Due to differences in synthesis methods, even if similar amounts of monomers with the same structure are used, 11.50 / I 11.30It can be seen from the table above that the value of I will differ. Specifically, by adopting the synthesis method in which solution B is added later, 11.50 / I 11.30 The polymers were synthesized with a value of 1.08 or less. In addition, by completing the polymerization reaction while leaving unreacted monomers, the I 11.50 / I 11.30 On the other hand, the I value of the polymer synthesized by bulk polymerization tends to be smaller. 11.50 / I 11.30 The value was over 1.08.

[0124] <Preparation and Evaluation of Photosensitive Resin Composition> The polymer and diazirine compound shown in Table 2 below were dissolved in propylene glycol monomethyl ether acetate (PGMEA), and the solution was filtered through a syringe filter made of polytetrafluoroethylene (PTFE) with a pore size of 0.22 μm, thereby preparing a photosensitive resin composition. The amount of PGMEA was set so that the polymer concentration in the resin composition would be 5% by mass. The diazirine compounds used were purchased from XlynX Materials Inc., a Canadian company, under the product numbers "BLD-201" and "BXW-202." For reference, the chemical structure of BLD-201 is shown below. The structure of BXW-202 is encompassed by the general formula (BB) shown above.

[0125] [ka]

[0126] The prepared photosensitive resin composition was spin-coated onto a silicon wafer at 1500 rpm for 30 seconds, and then pre-baked at 80° C. for 60 seconds to form a film with a thickness of 100 nm.

[0127] The formed film was irradiated with an electron beam at an acceleration voltage shown in Table 2 for an exposure dose shown in Table 2. For the evaluation described below, one resin film was scanned with the electron beam so as to obtain a 50 nm line / space pattern and a 200 μm × 200 μm solid film. Thereafter, development processing was carried out using a 2.38 mass % aqueous solution of tetramethylammonium hydroxide (TMAH) as a developer by the method described in Table 2 (immersion or spray) for the time described in Table 2. After the development process was completed, the silicon wafer was washed with deionized water and spin-dried. In this manner, a pattern was obtained on the silicon wafer.

[0128] The 50 nm line / space portion of the obtained pattern was photographed using an electron microscope, and the resolution was evaluated according to the following criteria. Very good: A 50nm line / space pattern was obtained without any breaks or peeling. Good: Although there were some breaks and peeling, a 50nm line / space pattern was obtained. Pattern not obtained: A 50 nm line / space pattern was not obtained.

[0129] Furthermore, the film thickness of the solid film portion was measured to determine the remaining film rate after development.

[0130] Table 2 summarizes information about the photosensitive resin composition.

[0131] [Table 2]

[0132] As shown in the above table, the compound has a structural unit represented by the general formula (NB) and a structural unit represented by the formula (MI-1), and 11.50 / I 11.30 The resin compositions of the examples prepared using polymers having a value of 1.08 or less exhibited good resolution when developed using a 2.38% by mass aqueous solution of TMAH. In contrast, the resin composition of the comparative example showed poor results in the evaluation of resolution in the development treatment using a 2.38 mass % TMAH aqueous solution.

[0133] As shown in Table 1, for example, the film formed using the polymer of Synthesis Example 1-1 and the film formed using the polymer of Comparative Synthesis Example 1 have similar alkali dissolution rates. However, while the photosensitive resin composition containing the polymer of Synthesis Example 1-1 had good resolution, the photosensitive resin composition containing the polymer of Comparative Synthesis Example 1 had poor resolution. This is thought to be due to differences in the arrangement of the structural units represented by formula (MI-1) in the polymer. For example, in the polymer of Synthesis Example 1-1, the structural units represented by formula (MI-1) containing alkali-soluble groups were properly arranged, i.e., not concentrated locally, which can be interpreted as allowing the penetration of the developer and the dissolution of the polymer by the developer to proceed uniformly throughout, resulting in high resolution. In contrast, in the polymer of Comparative Synthesis Example 1, the structural units represented by formula (MI-1) containing alkali-soluble groups were improperly arranged, i.e., concentrated locally, which can be assumed to cause the penetration of the developer and the dissolution of the polymer by the developer to proceed non-uniformly within the film, resulting in failure to obtain high resolution.

[0134] When the results were analyzed in more detail, for example, the resin composition containing the polymer of Synthesis Example 1-1 exhibited better resolution than the resin composition containing the polymer of Synthesis Example 1-2. 11.50 / I 11.30 The value of I of the polymer of Synthesis Example 1-2 is 0.73. 11.50 / I 11.30 The value of 1.06 can be interpreted as being related to this difference in results.

Claims

1. a polymer having a structural unit represented by the following general formula (NB) and a structural unit represented by the following formula (MI-1); A solvent, A resin composition comprising: The polymer was measured using dimethyl sulfoxide-d6 as the NMR solvent. １ The intensity at the chemical shift of 11.30 ppm in the H-NMR chart is １１．３０ , the intensity at the chemical shift of 11.50 ppm is I １１．５０ When I １１．５０ / I １１．３０ A resin composition having a value of 1.08 or less. 【Chemistry 1】 In the general formula (NB), R １ , R ２ , R ３ and R ４ are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms, provided that R １ , R ２ , R ３ and R ４ at least one of the groups is a group having an alkali-soluble group, a １ is 0, 1 or 2. 【Chemistry 2】

2. The resin composition according to claim 1, I １１．５０ / I １１．３０ A resin composition having a value of 0.50 or more.

3. The resin composition according to claim 1 or 2, The resin composition, wherein the polymer further has a structural unit represented by the following general formula (MI-2): 【Transformation 3】 In general formula (MI-2), X is a monovalent organic group containing a cyclic skeleton.

4. The resin composition according to claim 1 or 2, The group having an alkali-soluble group in the general formula (NB) is —C(CF ３ ) ２ A resin composition, which is a group having an OH group.

5. The resin composition according to claim 1 or 2, The resin composition, wherein the group having an alkali-soluble group in the general formula (NB) is a group represented by the following general formula (fa): -L-C(CF ３ ) ２ OH (fa) In general formula (fa), L is a single bond or an alkylene group having 1 to 6 carbon atoms.

6. The resin composition according to claim 3, A resin composition, wherein X in the general formula (MI-2) contains a cyclic aliphatic group.

7. The resin composition according to claim 1 or 2, the content ratio of the structural unit represented by general formula (NB) in the polymer is 1 to 50 mol %, The resin composition, wherein the content of the structural unit represented by formula (MI-1) in the polymer is 1 to 50 mol %.

8. The resin composition according to claim 1 or 2, A resin composition whose solubility in an alkaline developer changes upon exposure to actinic rays or radiation.

9. a first step of applying the resin composition according to claim 8 onto a substrate to form a resin film; a second step of irradiating the resin film with actinic rays or radiation; a third step of developing the resin film after the second step to obtain a substrate on which a resin pattern is formed; A pattern forming method comprising:

10. a fourth step of etching the substrate on which the resin pattern is formed, which is obtained by the pattern forming method according to claim 9; a removing step of removing the resin pattern remaining on the substrate after the fourth step; A method for manufacturing an electronic device, comprising:

11. A polymer having a structural unit represented by the following general formula (NB) and a structural unit represented by the following formula (MI-1): Measured using dimethyl sulfoxide-d6 as the NMR solvent １ The intensity at the chemical shift of 11.30 ppm in the H-NMR chart is １１．３０ , the intensity at the chemical shift of 11.50 ppm is I １１．５０ When I １１．５０ / I １１．３０ A polymer having a value of 1.08 or less. 【Chemistry 4】 In the general formula (NB), R １ , R ２ , R ３ and R ４ are each independently a hydrogen atom or an organic group having 1 to 30 carbon atoms, provided that R １ , R ２ , R ３ and R ４ at least one of the groups is a group having an alkali-soluble group, a １ is 0, 1 or 2. 【Transformation 5】

12. 12. The polymer of claim 11, I １１．５０ / I １１．３０ A polymer having a value of 0.50 or more.

13. 13. The polymer of claim 11 or 12, Further, a polymer having a structural unit represented by the following general formula (MI-2): 【Transformation 6】 In general formula (MI-2), X is a monovalent organic group containing a cyclic skeleton.

14. 13. The polymer of claim 11 or 12, The group having an alkali-soluble group in the general formula (NB) is —C(CF ３ ) ２ A polymer, which is a group having an OH group.

15. 13. The polymer of claim 11 or 12, A polymer, wherein the group having an alkali-soluble group in the general formula (NB) is a group represented by the following general formula (fa): -L-C(CF ３ ) ２ OH (fa) In general formula (fa), L is a single bond or an alkylene group having 1 to 6 carbon atoms.

16. 13. The polymer of claim 11 or 12, In the general formula (MI-2), X is a polymer containing a cycloaliphatic group.

17. 13. The polymer of claim 11 or 12, the content ratio of the structural unit represented by the general formula (NB) is 1 to 50 mol %, A polymer in which the content of the structural unit represented by formula (MI-1) is 1 to 50 mol %.

Images