JP2008292799A - Developer for photosensitive polyimide and pattern forming method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer for photosensitive polyimide which has little harmful effect on the human body, suppresses the generation of residues on and cracks in a pattern edge after development, and can achieve a high resolution and a high residual film ratio, and a pattern forming method using the same. <P>SOLUTION: The developer for photosensitive polyimide comprises: (a) 40-90 wt.% of a compound represented by general formula (1); (b) 5-50 wt.% of a ≤6C aliphatic alcohol; and (c) 5-20 wt.% of water, wherein R<SP>1</SP>and R<SP>2</SP>each represent hydrogen or a 1-10C organic group, provided that at least one of them is a 1-10C organic group in general formula (1). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a photosensitive polyimide developer and a pattern forming method using the same.

  Due to its excellent heat resistance, electrical properties, and mechanical properties, polyimide is widely used in electrical and electronic materials such as surface protective films for semiconductor elements and wiring, interlayer insulating films for multilayer wiring boards, and stress buffer coatings. Among these, photosensitive polyimide itself has pattern processability, so that the process can be simplified as compared with the case where non-photosensitive polyimide is patterned using a resist or the like.

  In the case of photosensitive polyimides, particularly negative photosensitive polyimides, organic developers are the mainstream of developers used for pattern processing. So far, for example, those containing dipolar aprotic solvents such as N-methyl-2-pyrrolidone and water (see, for example, Patent Document 1), dipolar aprotic such as N-methyl-2-pyrrolidone Solvents, those containing methanol and diethylene glycol solvents (for example, see Patent Document 2), dipolar aprotic solvents such as N-methyl-2-pyrrolidone, aromatic hydrocarbons and water (for example, patents) Document 3), dipolar aprotic solvents such as N-methyl-2-pyrrolidone, ester compounds such as propylene carbonate and propylene glycol monomethyl ether acetate, and water (for example, see Patent Document 4) are proposed. Has been. However, in recent years, there has been an increasing interest in the harmfulness of dipolar aprotic solvents to the human body, and as a developing solution for photosensitive polyimide, one that does not use these dipolar aprotic solvents as much as possible is required. . In addition, these organic developers show sufficient developability for photosensitive polyimide using a polyimide precursor, but when used for a photosensitive polyimide using a closed ring polyimide, the remaining film ratio is low. There was a problem that the pattern could not be formed.

On the other hand, as an organic developer not containing a dipolar aprotic solvent, for example, an organic developer containing cyclohexanone or cyclopentanone (for example, see Patent Documents 5-6) is disclosed. However, since these are not sufficiently soluble, there is a problem that residues and cracks are generated at the pattern edge after development.
JP 58-66940 A (first page) JP 58-223149 A (first page) Japanese Patent Laid-Open No. 4-133062 (first page) Japanese Patent Laid-Open No. 7-271053 (page 1-2) Japanese Patent Laid-Open No. 5-224419 (Example 1) Japanese Patent Laid-Open No. 2002-214801

  In view of the problems of the prior art, the present invention reduces pattern edge residues and cracks after development and achieves high resolution and a remaining film ratio with respect to a photosensitive polyimide using a closed ring polyimide. An object of the present invention is to provide a developer for photosensitive polyimide that can be used.

  That is, the present invention relates to (a) a compound represented by the following general formula (1): 40 to 90% by weight, (b) an aliphatic alcohol having 6 or less carbon atoms, 5 to 50% by weight, and (c) water 5 to 20% by weight. %, A developer for photosensitive polyimide.

In general formula (1), R ¹ and R ² each represent a hydrogen atom or an organic group having 1 to 10 carbon atoms. However, at least one is an organic group having 1 to 10 carbon atoms.

  According to the present invention, there is provided an excellent developer for polyimide that has little harm to the human body, reduces residue and cracks on the pattern edge after development, and can provide high resolution and a residual film ratio. Can do.

  The developer for photosensitive polyimide of the present invention (hereinafter sometimes referred to as developer) includes (a) a compound represented by the general formula (1), (b) an aliphatic alcohol having 6 or less carbon atoms, and (c ) It contains a specific amount of three components of water. By containing a specific amount of these components, it has sufficient dissolving power without using a dipolar aprotic solvent that has been pointed out to be harmful, reducing pattern edge residue after development, cracks, High resolution and residual film rate can be given. The developer of the present invention is particularly effective for a photosensitive polyimide containing a closed ring polyimide described later.

  The developer of the present invention contains (a) a compound represented by the following general formula (1) in an amount of 40 to 90% by weight in the developer. When it is less than 40% by weight, the solubility is insufficient and a residue is generated at the pattern edge. On the other hand, if it is more than 90% by weight, the solubility is too high and the remaining film ratio is lowered. Preferably, it is 60 to 90% by weight, and the residual film ratio can be further improved while reducing the residue at the pattern edge.

In the general formula (1), R ¹ and R ² each represent a hydrogen atom or an organic group having 1 to 10 carbon atoms. However, at least one is an organic group having 1 to 10 carbon atoms. Examples of the organic group having 1 to 10 carbon atoms include, but are not limited to, aliphatic hydrocarbons having 1 to 10 carbon atoms, and aliphatic hydrocarbons linked by ether or carbonyl. The organic group having 1 to 10 carbon atoms is preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a cyclohexyl group, a methoxymethyl group, an ethoxymethyl group, an ethoxyethyl group, an acetyl group, or an ethylcarbonyl group. Group, propylcarbonyl group, butylcarbonyl group and the like, but are not limited thereto.

  Preferred specific examples of the compound represented by the general formula (1) include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate. , Propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, and the like, but are not limited thereto. Among these, propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are more preferable because they can improve the remaining film rate. By using these compounds, there is an advantage that a high residual film ratio can be obtained. Moreover, only 1 type may be sufficient as the compound represented by General formula (1), and 2 or more types may be used for it.

  The developer of the present invention contains (b) 5 to 50% by weight of an aliphatic alcohol having 6 or less carbon atoms in the developer. If it is less than 5% by weight, the developer causes phase separation or the solubility is too high, resulting in a decrease in the remaining film ratio. On the other hand, if it exceeds 50% by weight, the pattern resolution is lowered. Preferably, it is 5 to 20% by weight, and the remaining film ratio and the pattern resolution can be compatible at a higher level.

  (B) Preferable specific examples of the aliphatic alcohol having 6 or less carbon atoms include, but are not limited to, methanol, ethanol, propanol, butanol, isopropanol, isobutanol, cyclohexanol, pentanol and the like. Moreover, only one type of aliphatic alcohol may be used, or two or more types may be used. Among these, methanol and ethanol are more preferable from the viewpoint of pattern resolution.

  The developer of the present invention contains (c) 5 to 20% by weight of water in the developer. If the amount is less than 5% by weight, the solubility is too high and the remaining film ratio is lowered or cracks are generated. On the other hand, when the content is more than 20% by weight, the developer causes phase separation, whitening of the film after development, a residue occurs on the pattern edge, or the resolution decreases.

  (C) From the request | requirement of the semiconductor field | area which is the main use of photosensitive polyimide, it is preferable that water does not contain metal ions, chloride ions, etc., such as ion-exchange water and distilled water.

  The developer of the present invention may contain an organic solvent other than the above (a) to (c). Preferred organic solvents for adjusting the development time include, but are not limited to, those having a high polarity such as ether and ester. Preferred specific examples include, but are not limited to, propylene carbonate, ethyl lactate, butyl acetate and the like. The content of the organic solvent other than (a) to (c) is preferably 30% by weight or less in the developer from the viewpoint of further improving the remaining film ratio.

  The developer of the present invention is prepared, for example, by mixing the above components (a) to (c) and other components as necessary, but is not limited to this method.

  The developer of the present invention is used as a developer for photosensitive polyimide. Here, the photosensitive polyimide refers to a photosensitive resin composition containing a polyimide precursor that can be converted into a polyimide by heat treatment, or a photosensitive resin composition containing a polyimide that is soluble in an organic solvent. Preferred specific examples of the negative photosensitive polyimide include those containing a polyimide precursor synthesized from an acid dianhydride and a diamine and an amine compound having a photoreactive double bond, or a photoreactive double Although what couple | bonded the coupling | bonding with the polymer via the ester group, the thing containing a polyimide precursor, a polyimide, and a (meth) acryl monomer, etc. are mentioned, It is not limited to these. In particular, the developer of the present invention has high solubility in (d) a negative photosensitive polyimide containing a polymer having a repeating structure represented by the following general formula (2).

In the general formula (2), R ³ represents a ^{4 to} 14 valent organic group, and R ⁴ represents a 2 to 12 valent organic group. R ⁵ and R ⁶ represent a phenolic hydroxyl group, a sulfonic acid group, a thiol group, or a carboxyl group, and may be the same or different. α and β represent an integer of 0 to 10.

In general formula (2), R ^3- (R ⁵ ) _α represents a residue of an acid dianhydride, and R ³ is a tetravalent to 14-valent organic group. Especially, it is preferable that it is a C5-C40 organic group containing an aromatic ring or a cycloaliphatic group.

  Preferable specific examples of the acid dianhydride include pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid Anhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane Aromatic tetracarboxylic dianhydrides such as dianhydrides, aliphatic tetracarboxylic dianhydrides such as butanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride Examples thereof include, but are not limited to, acid dianhydrides represented by the following general formula (3). These are used alone or in combination of two or more.

In the general formula (3), R ⁷ represents an oxygen atom, C (CF ₃ ) ₂ , C (CH ₃ ) ₂ or SO ₂ . R ⁸ and R ⁹ represent a hydrogen atom, a hydroxyl group or a thiol group.

In the general formula ^{(2), R 4 - (} R 6) β represents the residue of a diamine, ^{R 4} is 2 to 12 monovalent organic group. Among them, an organic group having 5 to 40 carbon atoms containing an aromatic ring or a cyclic aliphatic group is preferable.

  Preferred examples of the diamine include 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylsulfone, 4 , 4′-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfide, 4,4′-diaminodiphenylsulfide, m-phenylenediamine, p-phenylenediamine, 1,4-bis (4-aminophenoxy) benzene 9,9-bis (4-aminophenyl) fluorene and diamines represented by the following general formula (4) or (5), but are not limited thereto. These are used alone or in combination of two or more.

In the above formula, R ⁷ represents an oxygen atom, C (CF ₃ ) ₂ , C (CH ₃ ) ₂ or SO ₂ . R ⁸ and R ⁹ represent a hydrogen atom, a hydroxyl group or a thiol group.

In the general formula (2), R ⁵ and R ⁶ represent a phenolic hydroxyl group, a sulfonic acid group, a thiol group, or a carboxyl group. From the viewpoint of solubility in a developer, a phenolic hydroxyl group, a sulfonic acid group, and a thiol group, which are polar groups having active hydrogen, are preferable.

In the general formula (2), alpha, beta denotes the number of ^R 5, ^{R 6} each represent an integer of 0.

  The polyimide having the structural unit represented by the general formula (2) preferably has at least one group selected from the group consisting of a carboxyl group, a phenolic hydroxyl group, a sulfonic acid group, and a thiol group at the end of the main chain. . These active hydrogen-containing polar groups can be introduced to the ends of the main chain by making the end-capping agent have an active hydrogen-containing polar group. As the end-capping agent, monoamine, acid anhydride, monocarboxylic acid, monoacid chloride compound, monoactive ester compound and the like can be used.

  Preferred examples of monoamines used as end-capping agents include 5-amino-8-hydroxyquinoline, 1-hydroxy-7-aminonaphthalene, 1-hydroxy-6-aminonaphthalene, 1-hydroxy-5-aminonaphthalene, 1 -Hydroxy-4-aminonaphthalene, 2-hydroxy-7-aminonaphthalene, 2-hydroxy-6-aminonaphthalene, 2-hydroxy-5-aminonaphthalene, 1-carboxy-7-aminonaphthalene, 1-carboxy-6 Aminonaphthalene, 1-carboxy-5-aminonaphthalene, 2-carboxy-7-aminonaphthalene, 2-carboxy-6-aminonaphthalene, 2-carboxy-5-aminonaphthalene, 2-aminobenzoic acid, 3-aminobenzoic acid 4-aminobenzoic acid, 4-aminosalicylic acid 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzenesulfonic acid, 3-aminobenzenesulfonic acid, 4-aminobenzenesulfonic acid, 3-amino-4,6-dihydroxypyrimidine, 2-aminophenol, 3-amino Examples include phenol, 4-aminophenol, 2-aminothiophenol, 3-aminothiophenol, and 4-aminothiophenol. These are used alone or in combination of two or more.

  Preferred examples of acid anhydrides, monocarboxylic acids, monoacid chloride compounds, and monoactive ester compounds used as end-capping agents include phthalic anhydride, maleic anhydride, nadic acid, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic acid. Acid anhydrides such as acid anhydrides, 3-carboxyphenol, 4-carboxyphenol, 3-carboxythiophenol, 4-carboxythiophenol, 1-hydroxy-7-carboxynaphthalene, 1-hydroxy-6-carboxynaphthalene, 1 -Hydroxy-5-carboxynaphthalene, 1-mercapto-7-carboxynaphthalene, 1-mercapto-6-carboxynaphthalene, 1-mercapto-5-carboxynaphthalene, 3-carboxybenzenesulfonic acid, 4-carboxybenzenesulfonic acid Which monocarboxylic acids and monoacid chloride compounds in which these carboxyl groups are acid chlorides and terephthalic acid, phthalic acid, maleic acid, cyclohexanedicarboxylic acid, 1,5-dicarboxynaphthalene, 1,6-dicarboxynaphthalene, 1, Mono-acid chloride compounds in which only the monocarboxyl group of dicarboxylic acids such as 7-dicarboxynaphthalene and 2,6-dicarboxynaphthalene is acid chloride, monoacid chloride compounds and N-hydroxybenzotriazole and N-hydroxy-5-norbornene Examples include active ester compounds obtained by reaction with -2,3-dicarboximide. These are used alone or in combination of two or more.

  The introduction ratio of the monoamine used for the terminal blocking agent is preferably 0.1 mol% or more, particularly preferably 5 mol% or more, preferably 60 mol% or less, particularly preferably 50, based on the total amine component. It is less than mol%. The introduction ratio of the acid anhydride, monocarboxylic acid, monoacid chloride compound or monoactive ester compound used as the end-capping agent is preferably 0.1 mol% or more, particularly preferably 5 mol%, relative to the diamine component. Or more, preferably 100 mol% or less, particularly preferably 90 mol% or less. A plurality of different end groups may be introduced by reacting a plurality of end-capping agents.

Furthermore, in order to improve the adhesion to the substrate, an aliphatic group having a siloxane structure may be used for R ³ , R ⁴ , and R ⁷ as long as the heat resistance is not lowered. Specific examples of the diamine component include those obtained by copolymerizing 1 to 10 mol% of bis (3-aminopropyl) tetramethyldisiloxane, bis (p-amino-phenyl) octamethylpentasiloxane, and the like.

  The polyimide used in the present invention may be composed only of the repeating structure represented by the general formula (2), or may be a copolymer or a mixture with other repeating structures. At that time, the repeating structure represented by the general formula (2) is preferably contained in an amount of 10% by weight or more, preferably 50% by weight or more of the whole polyimide. If it is this range, there exists an advantage which can obtain a higher residual film rate. The type and amount of structural units used for copolymerization or mixing are preferably selected within a range that does not impair the heat resistance of the polyimide obtained by the final heat treatment.

  The polyimide used in the present invention is synthesized using a known method. For example, a method of reacting a tetracarboxylic dianhydride and a diamine compound (partially substituted with a monoamine) at a low temperature, a tetracarboxylic dianhydride (partially an acid anhydride, a monoacid chloride compound, or a mono A method of reacting an active ester compound) with a diamine compound, a diester obtained by tetracarboxylic dianhydride and an alcohol, and then reacting in the presence of a diamine (partially substituted with a monoamine) and a condensing agent, tetra Diester is obtained with carboxylic dianhydride and alcohol, then the remaining dicarboxylic acid is converted to acid chloride, and the polymer obtained by a method such as a method of reacting with diamine (partially substituted with monoamine) is used for known imidization reaction. Method to completely imidize using the method, or stop the imidization reaction in the middle, partially imide structure How to enter, and further, a fully imidized polymer, by mixing the polyimide precursor can be synthesized by utilizing a method of introducing a portion imide structure.

  The negative photosensitive polyimide used in the present invention preferably contains a photopolymerizable compound. The photopolymerizable compound referred to here contains a polymerizable unsaturated functional group. Examples of the polymerizable unsaturated functional group include unsaturated double bond functional groups such as vinyl group, allyl group, acryloyl group, methacryloyl group and / or unsaturated triple bond functional groups such as propargyl. Conjugated vinyl groups, acryloyl groups, and methacryloyl groups are preferred in terms of polymerizability. Moreover, it is preferable that it is 1-4 from the point of stability as the number which the functional group contains, and it does not need to be the same group, respectively. Further, the compound referred to here preferably has a molecular weight of 30 to 800. When the molecular weight is in the range of 30 to 800, the compatibility with the polyimide is good, and the stability of the photosensitive polyimide solution is good.

  Examples of the photopolymerizable compound include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane diacrylate, and trimethylolpropane. Triacrylate, trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate, styrene, α-methylstyrene, 1,2-dihydronaphthalene, 1,3-diisopropenylbenzene, 3-methylstyrene, 4-methylstyrene, 2- Vinyl naphthalene, butyl acrylate, butyl methacrylate, isobutyl acrylate, hexyl acrylate Isooctyl acrylate, isobornyl acrylate, isobornyl methacrylate, cyclohexyl methacrylate, 1,3-butanediol diacrylate, 1,3-butanediol dimethacrylate, neopentyl glycol diacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, dimethylol-tricyclode Candiacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate Rate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 1,3-diacryloyloxy-2-hydroxypropane, 1,3-dimethacryloyloxy-2-hydroxy Propane, methylenebisacrylamide, N, N-dimethylacrylamide, N-methylolacrylamide, 2,2,6,6-tetramethylpiperidinyl methacrylate, 2,2,6,6-tetramethylpiperidinyl acrylate, N- Methyl-2,2,6,6-tetramethylpiperidinyl methacrylate, N-methyl-2,2,6,6-tetramethylpiperidinyl acrylate, ethylene oxide-modified bisphenol A diacrylate, ethyl Oxide-modified bisphenol A dimethacrylate, N-vinylpyrrolidone, N-vinylcaprolactam and the like. These may be used alone or in combination of two or more.

  Of these, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, dimethylol-tricyclodecane diacrylate, isobornyl acrylate, isobornyl methacrylate, pentaerythritol triacrylate, penta Erythritol tetraacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, methylenebisacrylamide, N, N-dimethylacrylamide, N-methylolacrylamide, 2,2,6,6- Tetramethylpiperidinyl methacrylate, 2,2,6,6-tetramethylpiperidinyl acrylate, N-methyl -2,2,6,6-tetramethylpiperidinyl methacrylate, N-methyl-2,2,6,6-tetramethylpiperidinyl acrylate, ethylene oxide modified bisphenol A diacrylate, ethylene oxide modified bisphenol A dimethacrylate, N-vinyl pyrrolidone, N-vinyl caprolactam, etc. are mentioned.

  In the present invention, the content of the photopolymerizable compound is 5 parts by weight with respect to 100 parts by weight of the polymer (d) in order to prevent elution of the exposed part during development and to further improve the residual film ratio after development. The above is preferable. Moreover, from a viewpoint of suppressing the whitening of the film | membrane at the time of film formation, 200 weight part or less is preferable and 150 weight part or less is more preferable.

  Next, a pattern forming method using the developer of the present invention will be described. Although the photosensitive polyimide pattern-formed using the developing solution of the present invention is not particularly limited, the developing solution of the present invention has a repeating structure represented by (d) the following general formula (2). In particular, when a negative photosensitive polyimide containing the polymer is used, an excellent effect is obtained. Hereinafter, a pattern forming method using such a negative photosensitive polyimide will be described.

  The pattern forming method of the present invention comprises at least (1) a step of selectively exposing the negative photosensitive polyimide film formed on a substrate using a photomask, and (2) claim 1 or 2. The process which develops a photosensitive polyimide film using the developing solution for photosensitive polyimides in this order is provided.

  Examples of the method for forming the negative photosensitive polyimide film on the substrate include, but are not limited to, a method of applying photosensitive polyimide on a suitable substrate. Examples of the material for the substrate include, but are not limited to, metal, glass, semiconductor, metal oxide insulating film, silicon nitride, and the like. As a coating method, means such as spin coating using a spinner, spray coating using a spray coater, dipping, printing, roll coating, and the like can be employed. For the application of the photosensitive polyimide composition, a spin coater for photoresist can be used as it is. You may dry the board | substrate which apply | coated photosensitive polyimide as needed. Drying is performed using an oven, a hot plate, infrared rays, or the like, preferably at 15 to 150 ° C, more preferably at 40 to 100 ° C. The drying time is preferably 10 seconds to several hours. Also, if the film is already dried immediately after application, the drying step can be omitted.

Next, (1) the photosensitive polyimide film is selectively exposed using a photomask. The photosensitive polyimide film obtained by the above method is exposed using a mask having a desired pattern. The exposure amount is preferably 50 to 1000 mJ / cm ² , more preferably 100 to 600 mJ / cm ² . By using an appropriate sensitizer, exposure can be performed using an exposure machine such as an i-line stepper, a g-line stepper, a mask aligner, or a mirror projection aligner.

  If the resolution of the pattern at the time of development is improved or the allowable range of development conditions is increased, a baking process may be incorporated before development. This temperature is preferably in the range of 30 to 150 ° C, more preferably 40 to 100 ° C. The time is preferably 10 seconds to several hours. If these conditions are not met, there is a risk that the reaction will not proceed or the entire region will not dissolve, so care must be taken.

  Next, (2) the photosensitive polyimide film is developed using the developer for photosensitive polyimide according to claim 1 or 2, and the non-irradiated portion is dissolved and removed with the developer to obtain a relief pattern. Development can be carried out by a method such as irradiating the developer of the present invention directly or in the form of a mist on the coating film surface, immersing in the developer, or applying ultrasonic waves while immersing.

Next, it is preferable to wash the relief pattern formed by development using water or an organic solvent. Examples of the cleaning liquid include methanol, ethanol, isopropyl alcohol, ethyl lactate, ethyl pyruvate, propylene glycol monomethyl ether acetate, methyl-3-methoxypropionate, ethyl-3-ethoxypropionate, 2-heptanone, and ethyl acetate. Preferably used.

  The relief pattern obtained by the above treatment becomes a heat resistant resin film excellent in heat resistance and chemical resistance through the removal of residual solvent and additives by heat treatment. The heat treatment temperature is preferably 200 to 500 ° C, more preferably 300 to 400 ° C. Such heat treatment is preferably performed while raising the temperature stepwise or continuously.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these.

Synthesis example 1
Under a dry nitrogen stream, 2,032 g (0.082 mol) of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, 1,3-bis (3-aminopropyl) tetramethyldisiloxane 24 g (0.005 mol) and 2.73 g (0.025 mol) of 3-aminophenol as an end-capping agent were dissolved in 100 g of N-methyl-2-pyrrolidone (NMP). To this was added 31.02 g (0.10 mol) of bis (3,4-dicarboxyphenyl) ether dianhydride together with 30 g of NMP, stirred at 20 ° C. for 1 hour, and then at 180 ° C. for 4 hours while removing water. Stir. After completion of the reaction, the solution was poured into 2 L of water, and the precipitate of polymer powder was collected by filtration. The precipitate was collected by filtration and washed three times with water, and then the polymer powder was dried with a vacuum dryer at 80 ° C. for 20 hours.

  Next, 0.5 g of the oxime compound CGI-242 (trade name, manufactured by Ciba Specialty Chemicals Co., Ltd.) represented by the general formula (6) of the photopolymerization initiator is added to 15.0 g of the polymer powder, and the general formula (7 ) MX-270 (trade name, manufactured by Nippon Carbide Co., Ltd.) 1.5 g, trimethylolpropane triacrylate 7 g, and isobornyl acrylate 3 g are dissolved in 10 g of ethyl lactate to obtain a negative type Varnish A of the photosensitive polyimide composition was obtained.

  The pattern evaluation was performed by the following method.

1) Residual film ratio, resolution 3 g of varnish A was dropped on a 4-inch silicon wafer and spin-coated for 30 seconds, and then a hot plate at 100 ° C. (apparatus: SKW-636 manufactured by Dainippon Screen Mfg. Co., Ltd.) And baked for 3 minutes. At this time, the coating rotation was adjusted so that the film thickness after baking was about 8 μm. Subsequently, it exposed using the mask aligner (PLA-501F made from Canon). The exposure measured by i-line was 300 mJ / cm ² .

  After exposure, the film was baked for 1 minute on a 120 ° C. hot plate (apparatus: SKW-636 manufactured by Dainippon Screen Mfg. Co., Ltd.), and then the film thickness after baking was measured. Then, it developed with the developing solution of Examples 1-9 and Comparative Examples 1-7, and rinsed with isopropyl alcohol and dried.

  The film thickness after development was measured, and the value of (film thickness after development / film thickness after baking) × 100 was defined as the residual film ratio. Further, the smallest resolution of the square via-hole pattern was defined as the resolution, and 50 μm or less was accepted and those exceeding 50 μm were rejected.

2) Pattern edge residue and cracks Pattern processing was performed in the same manner as in 1) above, and first, it was visually observed whether there was any abnormality on the film surface after development. Then, a 20 μm square via hole pattern was observed with an optical microscope. At this time, if there was a crack in the corner of the pattern, it was considered as a crack and was rejected. Moreover, the pattern edge of the same pattern was observed, and the thing with the image development residue was considered to have a residue, and was rejected.

Examples 1-9, Comparative Examples 1-9
Pattern processing was performed using a developer prepared according to the composition table shown in Table 1. The evaluation results are shown in Table 1.

Claims (3)

(A) containing 40 to 90% by weight of a compound represented by the following general formula (1), (b) 5 to 50% by weight of an aliphatic alcohol having 6 or less carbon atoms, and (c) 5 to 20% by weight of water. A developing solution for photosensitive polyimide.

(In General Formula (1), R ¹ and R ² each represent a hydrogen atom or an organic group having 1 to 10 carbon atoms, provided that at least one is an organic group having 1 to 10 carbon atoms.) The developer for a photosensitive polyimide according to claim 1, wherein the compound represented by (a) the general formula (1) contains propylene glycol monomethyl ether acetate and / or propylene glycol monomethyl ether. At least (1) a negative photosensitive polyimide film containing a polymer having a repeating structure represented by the following general formula (2) formed on a substrate (d) is selectively exposed using a photomask. And (2) a pattern forming method comprising developing the negative photosensitive polyimide film in this order using the photosensitive polyimide developer according to claim 1 or 2.

(In the general formula (2), R ³ represents a ^{4 to} 14 valent organic group, R ⁴ represents a 2 to 12 valent organic group. R ⁵ and R ⁶ represent a phenolic hydroxyl group, a sulfonic acid group, a thiol group, or Represents a carboxyl group, which may be the same or different, and α and β each represent an integer of 0 to 10.)