JP5120539B2 - Heat resistant resin composition - Google Patents

Description

  The present invention relates to a resin composition serving as a precursor of a polybenzoxazole resin used as a surface protective film or an interlayer insulating film of a semiconductor device, a method for producing a cured relief pattern having heat resistance using the resin composition, The present invention also relates to a semiconductor device having the cured relief pattern.

  Conventionally, polybenzoxazole (hereinafter also referred to as PBO) resin having excellent heat resistance, electrical characteristics, mechanical characteristics, and the like has been used for a surface protective film and an interlayer insulating film of a semiconductor device. Since this PBO resin has low solubility in various solvents, it is generally used as a composition dissolved in a solvent in the form of a precursor hydroxypolyamide. Therefore, in use, a curing step is required in which the precursor is closed (closed to an oxazole ring) and converted to a PBO resin. This ring closing process is usually performed by thermosetting which is heated to 300 ° C. or higher.

However, in recent years, semiconductor devices that are inferior in heat resistance compared to conventional products have been developed, and a reduction in the thermosetting temperature as a surface protective film or an interlayer insulating film is required, and in particular, thermosetting at 280 ° C. or lower is required. There are many things that can be done. However, in the conventional PBO precursor resin composition, the ring closure reaction from the PBO precursor to PBO does not proceed sufficiently in the region of 280 ° C. or lower, and thus the film obtained by curing at a temperature of 280 ° C. or lower. Did not have the excellent heat resistance, electrical properties, mechanical properties, etc. expected of PBO.
Conventionally, it has been known that the use of a dehydrating agent such as concentrated sulfuric acid, phosphorus oxychloride, polyphosphoric acid or the like is effective for proceeding the ring-closing reaction to the oxazole ring at a low temperature (for example, see Non-Patent Document 1). . However, it is not appropriate to add these dehydrating agents to the PBO precursor resin composition in view of the stability of the composition, and no satisfactory one has been proposed yet.

  Furthermore, the PBO precursor resin composition is often used as a positive photosensitive resin composition that can be developed with an alkaline aqueous solution (see, for example, Patent Document 1). The development mechanism of this positive photosensitive resin is that the photosensitive diazoquinone compound in the unexposed area is insoluble in the alkaline aqueous solution, but the photosensitive diazoquinone compound undergoes a chemical change upon exposure to become an indenecarboxylic acid compound. It makes use of being soluble in an alkaline aqueous solution. By utilizing the difference in the dissolution rate with respect to the developer between the exposed portion and the unexposed portion, it becomes possible to produce a relief pattern of only the unexposed portion.

When the PBO precursor resin composition is used for a positive photosensitive resin composition containing a photosensitive diazoquinone compound, it is more difficult to select a method for promoting the ring closure to the oxazole ring from the viewpoint of stability and lithography performance. It is. On the other hand, Patent Document 2 proposes a photosensitive resin composition containing an amine imide compound that generates a base by heating in addition to a polyoxazole precursor and a compound that generates an acid upon irradiation with actinic rays. Further, Patent Document 3 proposes a positive photosensitive resin composition comprising an alkali-soluble resin, a diazoquinone compound, and an aliphatic sulfonic acid compound as a positive photosensitive resin composition having excellent low-temperature curability. Patent Document 4 includes a hydroxypolyamide, an ester compound, and a photosensitive diazoquinone compound as a positive photosensitive resin composition in which the ring closure reaction of PBO proceeds sufficiently even when used at a low thermosetting temperature. A characteristic positive photosensitive resin composition has been proposed.
Compared with these techniques, the heat-resistant resin composition of the present invention satisfies the cyclization reaction to the oxazole ring at 280 ° C. or lower, the stability of the composition, and the lithography properties at a higher level.

Japanese Examined Patent Publication No. 63-096162 JP 2004-077551 A JP 2006-010781 A JP 2006-126809 A The Chemical Society of Japan "Experimental Chemistry Course 4th Edition Volume 24 Organic Synthesis VI" published by Maruzen Co., Ltd., p525

  The present invention comprises a heat-resistant resin composition in which the ring closing reaction of PBO proceeds sufficiently even when used at a low thermosetting temperature, a method for producing a cured relief pattern using the composition, and the cured relief pattern. An object is to provide a semiconductor device. Furthermore, in the case of containing a photosensitive diazoquinone compound, the PBO ring-closing reaction sufficiently proceeds even when used at a low thermosetting temperature, and a highly sensitive heat-resistant resin composition and the composition were used. It is an object of the present invention to provide a method for producing a cured relief pattern and a semiconductor device having the cured relief pattern.

As a result of intensive studies to solve the above problems, the inventor has obtained a heat-resistant resin composition that solves the above problems by combining a plasticizer with a hydroxy polyamide having a specific structure. The headline and the present invention were made.
That is, the first of the present invention is a heat resistant resin composition characterized by containing 1 to 50 parts by mass of a plasticizer with respect to 100 parts by mass of a hydroxypolyamide having a repeating unit represented by the following general formula (1). A heat-resistant resin characterized in that the plasticizer is at least one compound selected from phthalates, trimellitic esters, sulfonamides, epoxy, camphor, and nitrobiphenyl It is a composition .

Wherein X ₁ is a tetravalent organic group having at least 2 carbon atoms, X ₂ , Y ₁ and Y ₂ are divalent organic groups having at least 2 carbon atoms, m is 2 to 2 An integer of 1000, n is an integer of 0 to 500, and m / (m + n)> 0.5, where m dihydroxydiamide units including X ₁ and Y ₁ , and X ₂ and Y ₂ are (The order of arrangement of the n diamide units contained is not limited.)

Moreover, in the heat resistant resin composition of this invention, it is preferable to contain 1-50 mass parts of photosensitive diazoquinone compounds further.
Furthermore the plasticizer in the heat-resistant resin composition of the present invention, phthalic acid esters, more preferably at least one compound selected from the scan Ruhon'amido acids, more preferably the plasticizer is phthalate esters Most preferably it is.

In the second aspect of the present invention, (1) the above-mentioned heat-resistant resin composition is formed on a substrate in the form of a layer or a film, and (2) it is exposed with actinic radiation through a mask, or a light beam, an electron beam or It is a method for producing a cured relief pattern, characterized by directly irradiating an ion beam, (3) eluting and removing an exposed portion or an irradiated portion, and (4) heat-treating the obtained relief pattern.
Furthermore, a third aspect of the present invention is a semiconductor device having a cured relief pattern layer obtained by the above-described method for producing a cured relief pattern.

  According to the present invention, a novel heat-resistant resin composition in which the ring closure reaction of PBO proceeds sufficiently even when used at a low thermosetting temperature, a method for producing a cured relief pattern using the composition, and the cured relief pattern A semiconductor device is provided. Further, when a photosensitive diazoquinone compound is contained, a novel heat-resistant resin composition having high sensitivity, in addition to sufficiently progressing the ring-closing reaction of PBO even when used at a low thermosetting temperature, the composition An object of the present invention is to provide a method for producing a cured relief pattern using, and a semiconductor device having the cured relief pattern.

<Heat resistant resin composition>
Each component which comprises the heat resistant resin composition of this invention is demonstrated concretely below.
(A) Hydroxypolyamide The hydroxypolyamide, which is the base polymer of the heat-resistant resin composition of the present invention, is a polymer containing m dihydroxydiamide units of the following general formula (1). The dihydroxydiamide unit consists of a bisaminophenol having a structure of X ₁ (NH ₂ ) ₂ (OH) ₂ and a dicarboxylic acid having a structure of Y ₁ (COOH) ₂ . Here, the two groups of amino group and hydroxy group of the bisaminophenol are each in the ortho position, and the hydroxypolyamide is closed to change into polybenzoxazole which is a heat resistant resin. m is preferably in the range of 2 to 1000, more preferably in the range of 3 to 50, and most preferably in the range of 3 to 20. If necessary, the hydroxypolyamide may be condensed with n diamide units of the following general formula (1). The diamide unit is composed of a diamine having a structure of X ₂ (NH ₂ ) ₂ and a dicarboxylic acid having a structure of Y ₂ (COOH) ₂ . n is preferably in the range of 0 to 500, and more preferably in the range of 0 to 10. If the ratio of the diamide unit in the hydroxy polyamide is too high, the solubility in an alkaline aqueous solution used as a developer is lowered. Therefore, the value of m / (m + n) is preferably 0.5 or more, 0.7 More preferably, it is more preferably 0.8 or more.

Examples of the bisaminophenol having the structure of X ₁ (NH ₂ ) ₂ (OH) ₂ include 3,3′-dihydroxybenzidine, 3,3′-diamino-4,4′-dihydroxybiphenyl, and 4,4 ′. -Diamino-3,3'-dihydroxybiphenyl, 3,3'-diamino-4,4'-dihydroxydiphenylsulfone, 4,4'-diamino-3,3'-dihydroxydiphenylsulfone, bis- (3-amino- 4-hydroxyphenyl) methane, 2,2-bis- (3-amino-4-hydroxyphenyl) propane, 2,2-bis- (3-amino-4-hydroxyphenyl) hexafluoropropane, 2,2-bis -(4-amino-3-hydroxyphenyl) hexafluoropropane, bis- (4-amino-3-hydroxyphenyl) methane, 2,2-bis -(4-amino-3-hydroxyphenyl) propane, 4,4'-diamino-3,3'-dihydroxybenzophenone, 3,3'-diamino-4,4'-dihydroxybenzophenone, 4,4'-diamino- 3,3′-dihydroxydiphenyl ether, 3,3′-diamino-4,4′-dihydroxydiphenyl ether, 1,4-diamino-2,5-dihydroxybenzene, 1,3-diamino-2,4-dihydroxybenzene, 1 , 3-diamino-4,6-dihydroxybenzene and the like. These bisaminophenols may be used alone or in combination.

Particularly preferred among these bisaminophenols is when X ₁ is an aromatic group selected from the following.

_As the diamine having a structure of X _{2 (NH 2)} 2, an aromatic diamine, such as silicon diamine.
Among these, examples of the aromatic diamine include m-phenylenediamine, p-phenylenediamine, 2,4-tolylenediamine, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, and 4,4′-diamino. Diphenyl ether, 3,3′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, 3,4′- Diaminodiphenylmethane, 4,4′-diaminodiphenyl sulfide, 3,3′-diaminodiphenyl ketone, 4,4′-diaminodiphenyl ketone, 3,4′-diaminodiphenyl ketone, 2,2′-bis (4-aminophenyl) ) Propane, 2,2'-bis (4-aminophenyl) hexa Fluoropropane, 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4-methyl-2,4-bis (4-aminophenyl) -1-pentene, 4-methyl-2,4-bis (4-aminophenyl) -2-pentene, 1,4-bis (α, α-dimethyl-4-aminobenzyl) benzene, Imino-di-p-phenylenediamine, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene, 4-methyl-2,4-bis (4-aminophenyl) pentane, 5 (or 6) -amino-1- (4-aminophenyl) -1,3,3-trimethylindane, bis (p-aminophenyl) phosphine oxide, 4,4′-diaminoazobenzene, 4,4′-diamino Phenylurea, 4,4′-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl ] Hexafluoropropane, 2,2-bis [4- (3-aminophenoxy) phenyl] benzophenone, 4,4'-bis (4-aminophenoxy) diphenylsulfone, 4,4'-bis [4- (α, α-dimethyl-4-aminobenzyl) phenoxy] benzophenone, 4,4′-bis [4- (α, α-dimethyl-4-aminobenzyl) phenoxy] diphenylsulfone, 4,4′-diaminobiphenyl, 4,4 '-Diaminobenzophenone, phenylindanediamine, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-di Aminobiphenyl, o-toluidine sulfone, 2,2-bis (4-aminophenoxyphenyl) propane, bis (4-aminophenoxyphenyl) sulfone, bis (4-aminophenoxyphenyl) sulfide, 1,4- (4-amino) Phenoxyphenyl) benzene, 1,3- (4-aminophenoxyphenyl) benzene, 9,9′-bis (4-aminophenyl) fluorene, 4,4′-di- (3-aminophenoxy) diphenylsulfone, 4, 4′-diaminobenzanilide and at least one group selected from the group consisting of a chlorine atom, a fluorine atom, a bromine atom, a methyl group, a methoxy group, a cyano group, and a phenyl group, as the hydrogen atom of the aromatic nucleus of these aromatic diamines Or the compound substituted by the atom is mentioned.

  Further, silicon diamine can be selected in order to enhance the adhesion to the substrate. Examples of this include bis (4-aminophenyl) dimethylsilane, bis (4-aminophenyl) tetramethylsiloxane, and bis (4 -Aminophenyl) tetramethyldisiloxane, bis (γ-aminopropyl) tetramethyldisiloxane, 1,4-bis (γ-aminopropyldimethylsilyl) benzene, bis (4-aminobutyl) tetramethyldisiloxane, bis ( γ-aminopropyl) tetraphenyldisiloxane and the like.

Moreover, as a preferable dicarboxylic acid having a Y ₁ (COOH) ₂ or Y ₂ (COOH) ₂ structure, Y ₁ and Y ₂ may be aromatic groups selected from the following.
(In the formula, A is a divalent group selected from the group consisting of —CH ₂ —, —O—, —S—, —SO ₂ —, —CO—, —NHCO—, —C (CF ₃ ) ₂ —. Means a group of

  Among these, preferred examples of dicarboxylic acids include 4,4′-diphenyl ether dicarboxylic acid and isophthalic acid. Used in the synthesis of natural hydroxypolyamides.

In the hydroxypolyamide having the repeating unit represented by the general formula (1), it is also included in the scope of the present invention to seal the terminal group with a specific organic group.
Examples of such a blocking group include a group having an unsaturated bond as described in JP-A No. 05-197153, or 4-methylcyclohexyl-1,2-dicarboxylic anhydride. When sealed with these, it is expected that the mechanical properties (particularly elongation) of the coating film after heat curing and the cured relief pattern shape will be good. Preferable examples of such a sealing group include the following groups.

(B) Plasticizer In the heat resistant resin composition of the present invention, it is important to contain a plasticizer. Plasticizers include dimethyl phthalate, diethyl phthalate, dipropyl phthalate, diisopropyl phthalate, dibutyl phthalate, diisobutyl phthalate, diamyl phthalate, di-n-hexyl phthalate, dicyclohexyl phthalate, diheptyl phthalate, phthalic acid Di-n-octyl, dinonyl phthalate, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, ditridecyl phthalate, diphenyl phthalate, di (2-ethylhexyl) phthalate, di (2-butoxyethyl) phthalate, phthalate Phenylates such as benzyl 2-ethylhexyl acrylate, benzyl n-butyl phthalate, benzylisononyl phthalate, dimethyl isophthalate, trimellitic esters such as trimellitic acid tris (2-ethylhexyl), adipic acid Methyl, diethyl adipate, di-n-propyl adipate, diisopropyl adipate, diisobutyl adipate, diisononyl adipate, diisodecyl adipate, di (2-butoxyethyl) adipate, di (2-ethylhexyl) adipate, adipine Di (butyldiglycol) acid, heptylnonyl adipate, dimethyl azelate, di (2-ethylhexyl) azelate, diethyl succinate, dimethyl sebacate, diethyl sebacate, dibutyl sebacate, di-n-octyl sebacate, sebacin Dibasic acid di (2-ethylhexyl), dibutyl fumarate, di (2-ethylhexyl) fumarate, dimethyl maleate, diethyl maleate, di-n-butyl maleate, di (2-ethylhexyl) maleate, etc. Fatty acid Tellurium, trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri-n-amyl phosphate, triphenyl phosphate, tri-o-cresyl phosphate, trixylenyl phosphate, diphenyl 2-ethylhexyl phosphate, diphenyl phosphate Phosphate esters such as cresyl, tris (2-butoxyethyl) phosphate, tris (2-ethylhexyl) phosphate, diethylene glycol diacetylate, diethylene glycol dibenzoate, glycerol monooleate, glycerol tributyrate, glycerol triacetate, Esters of polyhydric alcohols such as triethylene glycol diacetate, trimethyl citrate, triethyl citrate, tri-n-propyl citrate, tributyl citrate, tri-n-amyl citrate, ethyl phthalyl ethyl Hydroxyglycolates such as luglycolate, butylphthalylbutylglycolate, triethyl O-acetylcitrate, tributyl O-acetylcitrate, methyl o-acetylricinoleate, p-toluenesulfonamide, N-methyl-p- Toluenesulfonamide, N-ethyl-p-toluenesulfonamide, N-cyclohexyl-p-toluenesulfonamide, N, N-diethyl-p-toluenesulfonamide, N, N-bis (2-hydroxyethyl) -p- Toluenesulfonamide, o-toluenesulfonamide, N-ethyl-o-toluenesulfonamide, benzenesulfonamide, Nn-butylbenzenesulfonamide, p-hydroxybenzenesulfonamide, o-nitrobenzenesulfonamide, p-nitroben Sulfonamides such as polysulfonamide, sulfanilamide, polyesters such as poly (1,3-butanediol adipate), SUNSOSIZER E-PS, SUNSOSIZER EP-O, SUNSOSIZER E-4030, SUNSOSIZER E-6000, Epoxy systems such as SUNSOSIZER E-2000H and SUNSOSIZER E-9000H (trade name, manufactured by Shin Nippon Chemical Co., Ltd.), Alfon UP-1000, Alfon UP-1010, Alfon UP-1021, Alfon UP-1061, Alfon UP-1080 , Alfon UP-1190, Alfon UG-4000, Alfon UG-4010 (trade name, manufactured by Toagosei Co., Ltd.), camphor, nitrobiphenyl, and the like.

Among these, the plasticizer is more preferably a compound selected from phthalic acid esters, dibasic fatty acid esters, and sulfonamides.
Furthermore, the plasticizer is most preferably a compound selected from phthalates.
When the above-mentioned plasticizer is added to the above-mentioned hydroxypolyamide, the cyclization reaction of PBO sufficiently proceeds even under heat treatment at a low temperature of 280 ° C. or less, and excellent heat resistance, electrical properties, mechanical properties, etc. are exhibited.
As addition amount of a plasticizer, 1-50 mass parts is preferable with respect to 100 mass parts of hydroxy polyamide, 10-50 mass parts is more preferable, 15-50 mass parts is further more preferable. If the added amount of the plasticizer is 1 part by mass or more, the effect of promoting cyclization of PBO can be obtained by heat treatment at a low temperature of 280 ° C. or less, and if it is 50 parts by mass or less, the properties of the obtained cured film may be impaired. Absent.

(C) Photosensitive diazoquinone compound The photosensitive diazoquinone compound used in the present invention is a compound having a 1,2-naphthoquinonediazide structure, and U.S. Pat. Nos. 2,772,972 and 2,797,213. No. 3,669,658, which is a known substance. As an example of a preferable thing, the following are mentioned, for example.

(In the formula, Q is a hydrogen atom or a naphthoquinonediazide sulfonic acid ester group shown below, and all Qs are not hydrogen atoms at the same time.)

Among these, the following are particularly preferable.

  1-50 mass parts is preferable with respect to 100 mass parts of this hydroxy polyamide, and, as for the compounding quantity to the hydroxy polyamide of the photosensitive diazoquinone compound, 10-30 mass parts is more preferable. If the blending amount of the photosensitive diazoquinone compound is 1 part by mass or more, the patterning property of the resin is good. Conversely, if it is 50 parts by mass or less, the tensile elongation rate of the cured film is maintained, and the development residue in the exposed part The occurrence of (scum) is suppressed.

(D) Other components In the heat-resistant resin composition of the present invention, if necessary, a dye, a surfactant, an adhesion aid for enhancing adhesion to the substrate, and a crosslinking agent can be added. is there.
The additives will be described more specifically. Examples of the dye include methyl violet, crystal violet, and malachite green.
As addition amount of dye, 0.1-30 mass parts is preferable with respect to 100 mass parts of hydroxy polyamide.

Examples of the surfactant include non-ionic surfactants made of polyglycols such as polypropylene glycol or polyoxyethylene lauryl ether, or derivatives thereof, such as Fluorard (trade name, manufactured by Sumitomo 3M), Megafuck ( Fluorosurfactants such as trade name, Dainippon Ink & Chemicals, Inc. or Sulflon (trade name, manufactured by Asahi Glass), such as KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), DBE (trade name, manufactured by Chisso Corporation ) And granol (trade name, manufactured by Kyoeisha Chemical Co., Ltd.) and the like.
As addition amount of surfactant, 0.01-10 mass parts is preferable with respect to 100 mass parts of hydroxy polyamide.

Examples of the adhesion assistant include alkyl imidazoline, butyric acid, alkyl acid, polyhydroxystyrene, polyvinyl methyl ether, t-butyl novolac, epoxy silane, epoxy polymer, and various silane coupling agents.
Specific preferred examples of the silane coupling agent include, for example, N-phenyl-3-aminopropyltrialkoxysilane, 3-mercaptopropyltrialkoxysilane, 2- (trialkoxysilylethyl) pyridine, and 3-methacryloxypropyl. Trialkoxysilane, 3-methacryloxypropyl dialkoxyalkylsilane, 3-glycidoxypropyltrialkoxysilane, 3-glycidoxypropyl dialkoxyalkylsilane, 3-aminopropyltrialkoxysilane or 3-aminopropyl dialkoxyalkyl Silane and acid anhydride or acid dianhydride reactant, 3-aminopropyltrialkoxysilane or 3-aminopropyl dialkoxyalkylsilane amino group converted to urethane group or urea group And the like of. In this case, methyl group, ethyl group, butyl group, etc. as the alkyl group, maleic anhydride, phthalic anhydride, etc. as the acid anhydride, pyromellitic dianhydride as the acid dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 4,4′-oxydiphthalic dianhydride, etc., t-butoxycarbonylamino group as a urethane group, phenylamino as a urea group Examples thereof include a carbonylamino group.
The addition amount of the adhesion assistant is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the hydroxy polyamide.

Examples of the crosslinking agent include 1,1,2,2-tetra (p-hydroxyphenyl) ethane, tetraglycidyl ether, glycerol triglycidyl ether, ortho-secondary butylphenyl glycidyl ether, 1,6-bis (2,3-epoxypropoxy ) Epoxy compounds such as naphthalene, diglycerol polyglycidyl ether, polyethylene glycol glycidyl ether, acetylacetone aluminum (III) salt, acetylacetone titanium (IV) salt, acetylacetone chromium (III) salt, acetylacetone magnesium (II) salt, acetylacetone magnesium (II) ) Salt, trifluoroacetylacetone aluminum (III) salt, trifluoroacetylacetone titanium (IV) salt, trifluoroacetylacetone chromium (III) salt, Metal chelating agents such as fluoroacetylacetone magnesium (II) salt and trifluoroacetylacetone nickel (II) salt, Nicalak MW-30MH, MW-100LH (trade name, manufactured by Sanwa Chemical Co., Ltd.), Cymel 300, Cymel 303 (trade name, And alkylated melamine resins such as Mitsui Cytec).
As addition amount of a crosslinking agent, 0.1-30 mass parts is preferable with respect to 100 mass parts of hydroxy polyamide.

(E) Solvent In the present invention, these components may be dissolved in a solvent to form a varnish and used as a heat resistant resin composition. Examples of such a solvent include N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether. , Propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-butylene glycol acetate, 1,3-butylene glycol-3-monomethyl ether, methyl pyruvate, ethyl pyruvate, methyl-3- Methoxypropionate or the like can be used alone or in combination. Of these solvents, non-amide solvents are preferable from the viewpoint of little influence on photoresists, and specific more preferable examples include γ-butyrolactone, cyclopentanone, cyclohexanone, isophorone and the like.
As addition amount of a solvent, 50-1000 mass parts is preferable with respect to 100 mass parts of hydroxy polyamide.

<Curing relief pattern and method for manufacturing semiconductor device>
Next, a method for producing a cured relief pattern by applying the heat resistant resin composition of the present invention to a substrate will be specifically described below.
First, the heat-resistant resin composition of the present invention is applied to a substrate such as a silicon wafer, a ceramic substrate, or an aluminum substrate by spin coating using a spinner or a roll coater. This is dried at 50 to 140 ° C. using an oven or a hot plate to remove the solvent.
Second, exposure with actinic radiation is performed through a mask using a contact aligner or a stepper, or light, electron beam, or ion beam is directly irradiated.
Third, the irradiated portion is dissolved and removed with a developer, and then rinsed with a rinse solution to obtain a desired relief pattern. As a developing method, methods such as spray, paddle, dip, and ultrasonic can be used. As the rinsing liquid, distilled water, deionized water or the like can be used.

The developer used for developing the resin film formed by the heat resistant resin composition of the present invention is for dissolving and removing the alkali-soluble polymer, and needs to be an alkaline aqueous solution in which an alkali compound is dissolved. . The alkali compound dissolved in the developer may be either an inorganic alkali compound or an organic alkali compound.
Examples of the inorganic alkali compound include lithium hydroxide, sodium hydroxide, potassium hydroxide, diammonium hydrogen phosphate, dipotassium hydrogen phosphate, disodium hydrogen phosphate, lithium silicate, sodium silicate, potassium silicate. Lithium carbonate, sodium carbonate, potassium carbonate, lithium borate, sodium borate, potassium borate, ammonia and the like.

Examples of the organic alkali compound include tetramethylammonium hydroxide, tetraethylammonium hydroxide, trimethylhydroxyethylammonium hydroxide, methylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, n-propylamine, diethylamine. -N-propylamine, isopropylamine, diisopropylamine, methyldiethylamine, dimethylethanolamine, ethanolamine, triethanolamine and the like.
Furthermore, if necessary, an appropriate amount of a water-soluble organic solvent such as methanol, ethanol, propanol, or ethylene glycol, a surfactant, a storage stabilizer, a resin dissolution inhibitor, or the like can be added to the alkaline aqueous solution.

Finally, the obtained relief pattern can be heat-treated to form a heat-resistant cured relief pattern having a polybenzoxazole structure. In this heat treatment, a temperature of 180 ° C. or higher is applied for 5 minutes or more, and a certain constant temperature may be maintained, or the temperature may be continuously increased. Preferred heat treatment conditions are such that the maximum temperature is 200 ° C. or higher and the time of 200 ° C. or higher is 30 minutes or longer.
Specifically, when the composition of the present invention is used for the production of a semiconductor device having inferior heat resistance, such as MRAM, organic semiconductor, and CMOS having copper wiring, which cannot be heated at 300 ° C. or higher, the heat treatment temperature is set to 180 to It is preferable to set it as 290 degreeC, and it is more preferable to set it as 220-250 degreeC. On the other hand, when used for the manufacture of a semiconductor device which does not have a problem in heating to 300 ° C. or higher, it is more preferably 300 to 350 ° C.

  The cured relief pattern created by the above-described manufacturing method is used to manufacture a known semiconductor device as a surface protective film, an interlayer insulating film, a rewiring insulating film, a flip chip device protective film, or a protective film for a device having a bump structure. A semiconductor device can be manufactured by combining with the method. It is also useful as interlayer insulation for multilayer circuits, cover coats for flexible copper-clad plates, solder resist films, liquid crystal alignment films, and the like.

The present invention will be described more specifically based on reference examples, examples, and comparative examples, but the present invention is not limited to these examples.
<Synthesis of hydroxy polyamide>
[Reference Example 1]
In a 2 L separable flask, 197.8 g (0.54 mol) of 2,2-bis (3-amino-4-hydroxyphenyl) -hexafluoropropane and 75.9 g of pyridine.
(0.96 mol) and 692 g of N, N-dimethylacetamide (hereinafter referred to as “DMAc”) were mixed and stirred at room temperature (25 ° C.) to dissolve. A solution obtained by dissolving 19.7 g (0.12 mol) of 5-norbornene-2,3-dicarboxylic anhydride in 88 g of diethylene glycol dimethyl ether (hereinafter referred to as “DMDG”) separately was added dropwise to the dropping funnel. . The time required for the dropwise addition was 40 minutes, and the maximum reaction solution temperature was 28 ° C.
After completion of the dropwise addition, the mixture was heated to 50 ° C. with a hot water bath and stirred for 18 hours, and then the IR spectrum of the reaction solution was measured to confirm that characteristic absorption of imide groups at 1385 cm ⁻¹ and 1772 cm ⁻¹ appeared.

Next, this was cooled to 8 ° C. with a water bath, and a solution obtained by dissolving 142.3 g (0.48 mol) of 4,4′-diphenyl ether dicarboxylic acid dichloride in 398 g of DMDG was added dropwise thereto from a dropping funnel. The time required for the dropping was 80 minutes, and the maximum reaction solution temperature was 12 ° C. Three hours after the completion of the dropping, the above reaction solution was dropped into 12 liters of water under high-speed stirring to disperse and precipitate the polymer, and this was recovered, washed with water and dehydrated appropriately, followed by vacuum drying to obtain hydroxypolyamide P-1. Obtained. The weight average molecular weight of the hydroxypolyamide thus synthesized by gel permeation chromatography (hereinafter also referred to as “GPC”) was 14,000 in terms of polystyrene. The analysis conditions for GPC are described below.
Column: manufactured by Showa Denko KK, trade name: Shodex, KF-807 / KF-806M / KF-806M / KF-802.5; serial eluent: tetrahydrofuran, 40 ° C
Flow rate: 1.0 ml / min Detector: Showa Denko, trade name: Shodex RI-101

  Further, when further purification of hydroxypolyamide is required, it can be carried out by the following method. That is, after re-dissolving the hydroxypolyamide obtained above in DMDG, this was treated with a cation exchange resin and an anion exchange resin, and the resulting solution was poured into ion exchange water and then precipitated hydroxy By purifying the polyamide by filtration, washing with water and vacuum drying, a purified hydroxypolyamide can be obtained.

[Reference Example 2]
In a 2 L separable flask, 171.4 g (0.47 mol) of 2,2-bis (3-amino-4-hydroxyphenyl) -hexafluoropropane, 71.2 g (0.90 mol) of pyridine, N, N -600 g of dimethylacetamide (hereinafter referred to as “DMAc”) was mixed and stirred at room temperature (25 ° C.) for dissolution. Separately, 6.1 g (0.04 mol) of 4-methylcyclohexyl-1,2-dicarboxylic anhydride was dissolved in 30 g of γ-butyrolactone (hereinafter referred to as “GBL”) from a dropping funnel. It was dripped. The time required for the dropwise addition was 10 minutes, and the maximum reaction solution temperature was 27 ° C.

After stirring for 5 hours, the reaction solution was analyzed by GPC (for low molecular weight measurement) and it was confirmed that 4-methylcyclohexyl-1,2-dicarboxylic anhydride had disappeared. The analysis conditions for GPC (for low molecular weight measurement) are described below.
Column: manufactured by Showa Denko KK, trade name: Shodex, KF-802 / KF-801 / KF-801; serial eluent: tetrahydrofuran, 40 ° C
Flow rate: 1.0 ml / min Detector: Showa Denko, trade name: Shodex RI-930

Next, this was cooled to −10 ° C. with a dry ice bath, and separately, 99.6 g (0.34 mol) of 4,4′-diphenyl ether dicarboxylic acid dichloride and 22.8 g (0.12 mol) of isophthaloyl chloride were added to 612 g of GBL. ) Was dissolved from the dropping funnel. The time required for the dropwise addition was 120 minutes, and the maximum reaction solution temperature was 2 ° C. Three hours after the completion of dropping, hydroxypolyamide P-2 having a weight average molecular weight of 25000 (polystyrene conversion) measured by GPC method was obtained.

<Synthesis of photosensitive diazoquinone compound>
[Reference Example 3]
In a 1 L separable flask, 109.9 g (0.3 mol) of 2,2-bis (3-amino-4-hydroxyphenyl) -hexafluoropropane, 330 g of tetrahydrofuran (THF), 47.5 g (0.6 mol) of pyridine. Into this, 98.5 g (0.6 mol) of 5-norbornene-2,3-dicarboxylic anhydride was added in powder form at room temperature. After stirring for 3 days at room temperature, the reaction was confirmed by HPLC. As a result, no starting material was detected and the product was detected as a single peak with a purity of 99%. This reaction solution was dropped as it was into 1 L of ion-exchanged water with stirring, and the precipitate was filtered off. Then, 500 mL of THF was added and dissolved by stirring. This homogeneous solution was dissolved in cation exchange resin: Amberlyst 15 (manufactured by Organo). ) The remaining pyridine was removed through a glass column packed with 100 g. Next, this solution was dropped into 3 L of ion exchange water under high-speed stirring to precipitate a product, which was filtered off and then vacuum-dried.
The product is imidized, it is not characteristic absorption of amide groups in the vicinity of 1540 cm ^-1 and 1650 cm ^-1 appear characteristic absorption of an imide group 1394Cm ^-1 and 1774 cm ^-1 in the IR spectrum is present, and NMR spectrum This was confirmed by the absence of amide and carboxylic acid proton peaks.

Next, 65.9 g (0.1 mol) of the product, 53.7 g (0.2 mol) of 1,2-naphthoquinonediazide-4-sulfonyl chloride and 560 g of acetone were added and dissolved by stirring at 20 ° C. A solution prepared by diluting 21.2 g (0.21 mol) of triethylamine with 106.2 g of acetone was added dropwise thereto at a constant rate over 30 minutes. At this time, the temperature of the reaction solution was controlled in the range of 20 to 30 ° C. using an ice water bath or the like.
After completion of the dropwise addition, the mixture was allowed to stir at 20 ° C. for another 30 minutes, and then 5.6 g of a 36 wt% hydrochloric acid aqueous solution was added at once. The reaction solution was then cooled in an ice water bath, and the precipitated solid was filtered off with suction. . The filtrate obtained at this time was dropped into 5 L of a 0.5% by weight aqueous hydrochloric acid solution over 1 hour with stirring to precipitate the desired product, which was collected by suction filtration. The obtained cake-like recovered material was again dispersed in 5 l of ion-exchanged water, stirred, washed, collected by filtration, and this water washing operation was repeated three times. Finally, the cake-like material obtained was vacuum-dried at 40 ° C. for 24 hours to obtain photosensitive diazoquinone compound Q-1.

<Preparation of heat resistant resin composition>
[Examples 1-5, Comparative Examples 1-3]
The photosensitive diazoquinone compound (Q-1) obtained in Reference Example 3 or the photosensitivity shown below with respect to 100 parts by mass of the hydroxypolyamide (P-1 or P-2) obtained in Reference Examples 1 and 2 above. The diazoquinone compound (Q-2, manufactured by Daitokemix Co., Ltd.) was added in the amount shown in Table 1, and the plasticizer shown below and other additives Z were added in the amounts shown in Table 1 and dissolved in 170 parts by mass of GBL. Then, it filtered with a 0.2 micrometer filter, and prepared the positive photosensitive heat-resistant resin composition of Examples 1-5 described in Table 1, and Comparative Examples 1-3.

<Evaluation of heat resistant resin composition>
(1) Evaluation of Oxazolization Rate The above heat-resistant resin composition was spin-coated on a 6-inch silicon wafer with a spin coater (Clean Track Mark-8) manufactured by Tokyo Electron Co., Ltd., and 120 on a hot plate.
Pre-baking was performed at 180 ° C. for 180 seconds to form a coating film. In a vertical curing furnace (manufactured by Koyo Lindberg), curing (heat curing treatment) was performed in a nitrogen atmosphere at 250 ° C. or 350 ° C. for 1 hour. The IR spectrum of the obtained cured film was measured by a microscopic ATR method, and after adjusting the size of each spectrum using the peak at 1490 cm ⁻¹ as a reference, the peak at 1050 cm ⁻¹ which is the characteristic absorption of the oxazole ring was measured. Using the size, the oxazolation rate at 250 ° C. when the oxazolation rate at 350 ° C. was taken as 100% was calculated according to the following formula and shown in Table 2.
Oxazole rate (%) = (250 ℃ heat treatment the peak height of the sample 1050cm ^-1) ÷ (350 ℃ heat treatment the peak height of 1050 cm ^-1 of sample) × 100

(2) Viscosity change rate evaluation The viscosity change rate after standing at 23 ° C. for 1 week was measured as follows and shown in Table 2. If the rate of change in viscosity was within 5%, the stability was considered good.
Viscosity change rate (%) = (viscosity after standing for 1 week−viscosity immediately after preparation of heat resistant resin composition) ÷ viscosity immediately after preparation of heat resistant resin composition × 100

(3) Sensitivity evaluation The heat resistant resin compositions of Examples 1 to 5 and Comparative Examples 1 to 3 were spin-coated on a 6-inch silicon wafer with a spin coater (clean track Mark-8) manufactured by Tokyo Electron, Pre-baking was performed at 120 ° C. for 180 seconds on a hot plate to form a coating film having a thickness of 10.7 μm. The film thickness was measured with a film thickness measuring device (Lambda Ace) manufactured by Dainippon Screen Mfg.
The obtained coating film was exposed with a stepper (NSR2005i8A) manufactured by Nikon Corporation having an exposure wavelength of i-line (365 nm) through a reticle with a test pattern while changing the exposure stepwise. This was developed using an alkali developer (AZ300MIF developer, 2.38 mass% tetramethylammonium hydroxide aqueous solution) manufactured by AZ Electronic Materials, so that the film thickness after development was 9.1 μm at 23 ° C. Development was carried out by adjusting the time to form a positive relief pattern. The sensitivity of the heat resistant resin composition is shown in Table 2.
The sensitivity of the heat resistant resin composition was evaluated as follows.
[Sensitivity (mJ / cm ² )]
Minimum exposure amount that can completely dissolve and remove the exposed portion of the coating film during the development time.

  From the examples, the composition to which the plasticizer which is an essential component of the present invention is added exhibits a sufficiently high oxazolation rate to obtain various properties expected as a final film, and is stable (viscosity change rate). There was no problem in patterning characteristics (sensitivity). On the other hand, the composition with no plasticizer added has a low oxazolation rate, and the composition with an acid-generating compound instead of a plasticizer adds heat, but the stability and patterning characteristics are poor. did.

  The heat resistant resin composition of the present invention includes a surface protective film for a semiconductor device, an interlayer insulating film, a rewiring insulating film, a protective film for a flip chip device, a protective film for a device having a bump structure, and an interlayer insulating film for a multilayer circuit It can be suitably used as a cover coat of a flexible copper-clad plate, a solder resist film, a liquid crystal alignment film, and the like.

Claims (6)

A heat-resistant resin composition containing 1 to 50 parts by mass of a plasticizer with respect to 100 parts by mass of a hydroxypolyamide having a repeating unit represented by the following general formula (1) , wherein the plasticizer is A heat-resistant resin composition, which is at least one compound selected from phthalates, trimellitic esters, sulfonamides, epoxy-based, camphor, and nitrobiphenyl .
Wherein X ₁ is a tetravalent organic group having at least 2 carbon atoms, X ₂ , Y ₁ and Y ₂ are divalent organic groups having at least 2 carbon atoms, m is 2 to 2 An integer of 1000, n is an integer of 0 to 500, and m / (m + n)> 0.5, where m dihydroxydiamide units including X ₁ and Y ₁ , and X ₂ and Y ₂ are (The order of arrangement of the n diamide units contained is not limited.)   Furthermore, 1-50 mass parts of photosensitive diazoquinone compounds are contained, The heat resistant resin composition of Claim 1 characterized by the above-mentioned. Plasticizer, phthalic acid esters, the heat-resistant resin composition according to claim 1 or 2, characterized in that at least one compound selected from the scan Ruhon'amido acids.   The heat-resistant resin composition according to claim 1 or 2, wherein the plasticizer is a phthalate ester. (1) The heat-resistant resin composition according to any one of claims 2 to 4 is formed on a substrate in the form of a layer or a film, and (2) exposure with actinic radiation through a mask, A method for producing a cured relief pattern, comprising directly irradiating an electron beam or an ion beam, (3) eluting and removing an exposed portion or an irradiated portion, and (4) heat-treating the obtained relief pattern. A semiconductor device comprising a cured relief pattern layer obtained by the method for producing a cured relief pattern according to claim 5 .