JP4329529B2 - Positive photosensitive resin composition, pattern forming method, and electronic component - Google Patents

Description

  Conventionally, polyimide resins having excellent heat resistance, electrical characteristics, mechanical characteristics, and the like have been used for surface protection films and interlayer insulating films of semiconductor elements. However, in recent years, as semiconductor elements have been highly integrated and increased in size, there has been a demand for thinner and smaller sealing resin packages, and LOC (lead-on-chip) and surface mounting methods such as solder reflow have been adopted. Therefore, a polyimide resin excellent in properties suitable for being formed as a protective film on the outermost surface of a semiconductor circuit, that is, mechanical properties, heat resistance, etc., is required more than ever. .

  On the other hand, a photosensitive polyimide having a photosensitive property imparted to a polyimide resin itself has been conventionally used because it has a feature that a pattern creating process can be simplified and a complicated manufacturing process can be shortened.

  The kind of heat-resistant photoresist using such a conventional photosensitive polyimide and its precursor is well known. For example, in a negative photosensitive resin, a polyimide obtained by a method of introducing a methacryloyl group into a polyimide precursor via an ester bond or an ionic bond (for example, see Patent Documents 1 to 4), a soluble material having a photopolymerizable olefin Polyimide (for example, see Patent Documents 5 to 10), self-sensitized polyimide having a benzophenone skeleton and an alkyl group at the ortho position of an aromatic ring to which a nitrogen atom is bonded (for example, see Patent Documents 11 and 12), etc. Is mentioned. These applications are also well known.

  However, the above-mentioned negative photosensitive resin has a problem of resolution caused by the absorption wavelength of the photosensitive agent, and a problem that a yield in manufacturing is reduced depending on applications. Moreover, since the structure of the polymer to be used is limited in the above polyimide resin, the physical properties of the finally obtained film are limited, and there are some which are not suitable for multipurpose applications.

  Furthermore, since the above-mentioned negative photosensitive resin requires an organic solvent such as N-methylpyrrolidone during development, a positive photosensitive resin that can be developed with an alkaline aqueous solution recently from the environmental viewpoint. Proposals have been made.

  In a positive photosensitive resin, for example, a method of introducing an o-nitrobenzyl group into a polyimide precursor via an ester bond (see, for example, Non-Patent Document 1), a naphthoquinonediazide compound in a soluble hydroxylimide or polyoxazole precursor Obtained by mixing a naphthoquinone diazide via an ester bond (for example, see Non-Patent Document 2), or a naphthoquinone diazide into a polyimide precursor. Are known (for example, see Patent Document 15).

  However, in the case of positive photosensitive resin as well as the negative photosensitive resin, the sensitivity and resolution are low due to the problems associated with the absorption wavelength of the photosensitive agent, and the structure of the polymer used as described above is limited. The same problem as that of the negative photosensitive resin occurs.

  In addition, a carboxylic acid such as a material obtained by mixing a polybenzoxazole precursor with a diazonaphthoquinone compound (for example, see Patent Document 16) or a material in which a phenol moiety is introduced into a polyamic acid via an ester bond (for example, see Patent Document 17). Although materials having phenolic hydroxyl groups introduced instead of these have been proposed, these materials have insufficient developability, causing problems such as film loss in unexposed areas and peeling of the resin from the substrate. For the purpose of improving developability and adhesion, a material in which a polyamic acid having a siloxane moiety in the polymer skeleton is mixed (see, for example, Patent Documents 18 and 19) has been proposed. Storage stability deteriorates due to the use of. Therefore, materials with amine end groups sealed with polymerizable groups (for example, see Patent Documents 20 to 22) have been proposed for the purpose of improving storage stability and adhesion, but these materials are acid generators. Since a diazoquinone compound containing a large number of aromatic rings is used, the mechanical properties after thermosetting are remarkably lowered and the sensitivity is low, so that it is difficult to say that the material is at a practical level. In order to compensate for this lack of sensitivity, a material using a highly transparent polybenzoxazole precursor has been proposed (see, for example, Patent Document 23), but as described above, the mechanical properties (mechanical strength) after thermosetting are reduced. The problem has not been solved.

  Materials to which various chemical amplification systems are applied have been proposed for the purpose of improving the problems of the diazoquinone compounds. Examples of materials to which this chemical amplification system is applied include chemical amplification type polyimide (see, for example, Patent Document 24), chemical amplification type polyimide, polybenzoxazole precursor (for example, see Patent Documents 25 to 31), and the like. Can be mentioned. However, among these, the high sensitivity one has a low molecular weight, and thus a decrease in film properties is observed. On the other hand, those having excellent film characteristics have a high molecular weight, so that the solubility is insufficient and a decrease in sensitivity is observed. Therefore, none of the materials is practically usable, and there is still no material at the practical level.

JP-A-49-115541 Japanese Patent Laid-Open No. 51-40922 JP 54-145794 A JP 56-38038 A JP 59-108031 A JP 59-220730 A JP 59-232122 A Japanese Unexamined Patent Publication No. 60-6729 JP-A-60-72925 JP-A-61-57620 JP 59-219330 A JP-A-231533 JP-A 64-60630 US Pat. No. 4,395,482 JP 52-13315 A Japanese Patent Publication No. 64-46862 JP-A-10-307393 JP-A-4-31861 Japanese Patent Laid-Open No. 4-46345 JP-A-5-197153 JP-A-9-183846 JP 2001-183835 A JP 2001-220443 A Japanese Patent Laid-Open No. 3-763 JP 7-219228 A Japanese Patent Laid-Open No. 10-186664 Japanese Patent Laid-Open No. 11-202489 JP 2001-56559 A JP 2001-194791 A JP 2002-526793 A US Pat. No. 6,143,467 J. et al. Macromol. Sci. Chem. , A24, 10, 1407, 1987 Macromolecules, 23, 1990

  The present invention is a positive-type photosensitive material that maintains mechanical properties (mechanical strength), has excellent sensitivity and resolution, and that the resin itself has appropriate solubility in an alkaline aqueous solution, and further has excellent adhesion and heat resistance. It aims at providing a conductive resin composition.

  In addition, the present invention provides a method for producing a pattern that is excellent in mechanical properties (mechanical strength), sensitivity, resolution, and heat resistance by using the composition, and that provides a pattern having a good shape. It is another object of the present invention to provide a highly reliable electronic component (semiconductor device) by having a pattern having a good shape and characteristics.

  In order to solve the above-mentioned problems, the present inventors first made extensive studies on improving sensitivity, and in the positive photosensitive resin composition, an aliphatic cyclic group such as a group having a specific structure or an adamantane residue. It has been found that if a polyoxazole precursor having an organic group having a structure is contained, transparency is improved and sensitivity is improved. Moreover, it discovered that the mechanical strength after thermosetting did not fall. Next, research was conducted on the improvement of developability with respect to an aqueous alkali solution, and it was found that if the molecular terminal of the polyoxazole precursor is sealed with an organic group, the resin itself has an appropriate solubility in the aqueous alkali solution. Furthermore, it has been clarified that an improvement in resolution can be observed by adding a compound capable of inducing the elimination reaction of the protecting group in the solubility converting agent by irradiation with radiation. The present invention has been completed based on these findings.

（式中、Ｒ ¹ は、下記一般式（２）

（式中、ｎは０〜１０の整数を示す。）で示される構造の基またはアダマンタン残基、Ｒ ² は四価の有機基、Ｒ ³ は一価の有機基を示し、いずれも複数ある場合は同一でも異なっていてもよく、ｎは繰り返し数を示す整数を示す。）で表されるポリオキサゾール前駆体と、
（Ｂ）活性光線照射により酸を発生する化合物と、
（Ｃ）酸触媒作用で分解して水素原子に変換し得る有機基を有する化合物とを含有してなることを特徴とするポジ型感光性樹脂組成物。
[２]前記一価の有機基Ｒ³が、アルキル基、アリール基、アセタールまたはケタールを構成する基、シリル基、シリルエーテル基、アルコキシカルボニル基、アルコキシアルキル基、アルキルシリル基からなる群より選ばれる少なくとも一つであることを特徴とする上記［１］に記載のポジ型感光性樹脂組成物。
[３]前記（Ｃ）成分が、分子中で芳香環に結合し、かつ−ＯＲ（但し、Ｒは酸の作用で分解し、水素原子に変換し得る一価の有機基を示す。）で示される基、及び／又は−ＣＯＯＲ（但し、Ｒは酸の作用で分解し、水素原子に変換し得る一価の有機基を示す。）で示される基を有する化合物であることを特徴とする上記［１］または［２］に記載のポジ型感光性樹脂組成物。
[４]前記（Ｃ）成分が、下記一般式（３）

（式中、Ｘは有機基、Ｒは酸の作用で分解し、水素原子に変換し得る一価の有機基を示し、いずれも複数ある場合は同一でも異なっていてもよい。ａ、ｂはそれぞれ０以上の整数であり、ａ＋ｂは１以上の整数を示す。）で表される化合物であることを特徴とする上記［１］〜［３］のいずれか１つに記載のポジ型感光性樹脂組成物。
[５]前記（Ｃ）成分が、下記一般式（４）

（式中、Ｘ’は有機基、Ｒは酸の作用で分解し、水素原子に変換し得る一価の有機基を示し、いずれも複数ある場合は同一でも異なっていてもよい。ａ、ｂはそれぞれ０以上の整数を示す。）で表される繰り返し単位を有する化合物であることを特徴とする上記［１］〜［３］のいずれか１つに記載のポジ型感光性樹脂組成物。
[６]上記［１］〜［５］のいずれか１つに記載のポジ型感光性樹脂組成物を支持基板上に塗布し、乾燥してポジ型感光性樹脂膜を得る工程と、前記ポジ型感光性樹脂膜を露光する工程と、前記露光後のポジ型感光性樹脂膜を加熱する工程と、前記加熱後のポジ型感光性樹脂膜をアルカリ水溶液を用いて現像する工程と、前記現像後のポジ型感光性樹脂膜を加熱処理する工程とを含むことを特徴とするパターンの形成方法。
[７]上記［６］に記載の形成方法により得られるパターンの層を有してなる電子デバイスを有する電子部品であって、前記電子デバイス中に前記パターンの層が層間絶縁膜層及び／又は表面保護膜層として設けられたものであることを特徴とする電子部品。 That is, the present invention relates to the following.
[1] (A) A polyoxazole precursor having an organic group having an aliphatic cyclic structure in the main chain , the following general formula (1)

(Wherein R ¹ represents the following general formula (2)

(Wherein n represents an integer of 0 to 10) or an adamantane residue, R ² is a tetravalent organic group, R ³ is a monovalent organic group, and there are a plurality of them. The cases may be the same or different, and n represents an integer indicating the number of repetitions. And a polyoxazole precursor represented by:
(B) a compound that generates an acid upon irradiation with actinic rays;
(C) A positive photosensitive resin composition comprising an organic group-containing compound that can be decomposed by acid catalysis and converted into a hydrogen atom.
[ 2 ] The monovalent organic group R ³ is selected from the group consisting of an alkyl group, an aryl group, an acetal or ketal group, a silyl group, a silyl ether group, an alkoxycarbonyl group, an alkoxyalkyl group, and an alkylsilyl group. The positive photosensitive resin composition as described in [1] above, wherein the positive photosensitive resin composition is at least one.
[ 3 ] The component (C) is bonded to an aromatic ring in the molecule and is —OR (wherein R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom). And / or -COOR (wherein R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom). The positive photosensitive resin composition according to the above [1] or [2] .
[ 4 ] The component (C) is represented by the following general formula (3)

(In the formula, X represents an organic group, R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom, and when there are a plurality of them, they may be the same or different. Each of which is an integer of 0 or more, and a + b represents an integer of 1 or more.) The positive photosensitive property as described in any one of [1] to [ 3 ] above, Resin composition.
[ 5 ] The component (C) is represented by the following general formula (4)

(In the formula, X ′ represents an organic group, R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom, and when there are a plurality of them, they may be the same or different. A, b Each represents an integer of 0 or more.) The positive photosensitive resin composition as described in any one of the above [1] to [ 3 ], which is a compound having a repeating unit represented by:
[ 6 ] Applying the positive photosensitive resin composition according to any one of the above [1] to [ 5 ] on a support substrate and drying to obtain a positive photosensitive resin film; A step of exposing the positive photosensitive resin film, a step of heating the positive photosensitive resin film after the exposure, a step of developing the positive photosensitive resin film after the heating using an alkaline aqueous solution, and the development method of forming a pattern which comprises a step of heating the positive photosensitive resin film after.
[ 7 ] An electronic component having an electronic device having a pattern layer obtained by the formation method described in [ 6 ] above, wherein the pattern layer is an interlayer insulating film layer and / or An electronic component provided as a surface protective film layer.

  The present invention is characterized in that, by adopting the above-described configuration, improvement in sensitivity and maintenance of mechanical strength, which could not be achieved by the conventional technology, can be realized at the same time.

  The positive photosensitive resin composition of the present invention is excellent in sensitivity, resolution and heat resistance while maintaining mechanical properties (mechanical strength). Further, according to the pattern forming method of the present invention, by using the composition, a pattern having a good shape and excellent mechanical properties, sensitivity, resolution and heat resistance can be obtained. In addition, the electronic component (semiconductor device) of the present invention is excellent in reliability by having a pattern with a good shape and characteristics.

Hereinafter, embodiments of the present invention will be described.
In the positive photosensitive resin composition of the present invention, the component (A) is a polyoxazole precursor having an organic group having an aliphatic cyclic structure in its main chain. More specifically, the following general formula It is a polyoxazole precursor having the structure represented by (1).

In the general formula (1), R ¹ represents an organic group having the aliphatic cyclic structure, R ² represents a tetravalent organic group, and R ³ represents a monovalent organic group. They may be different, and n represents an integer indicating the number of repetitions.

In the polyoxazole precursor, R ¹ in the structure represented by the general formula (1) is a group having the aliphatic cyclic structure. The group having an aliphatic cyclic structure is not particularly limited, but is preferably a group having a structure represented by the following general formula (2) or an adamantane residue. Preferred examples of the group having the structure represented by the following general formula (2) include cyclopropane, cyclobutane, cyclopentane, and cyclohexane. As the number of carbon atoms, 3 to 30 is preferable. In general formula (2), n represents an integer of 0 to 10.

  By having the group having the structure represented by the general formula (2) or the adamantane residue in the structure of the polyoxazole precursor, the transparency of the resin can be increased, and as a result, the sensitivity can be improved. it can. Further, the mechanical properties are improved by increasing the carbon density.

  Examples of the group having another aliphatic cyclic structure include those having a skeleton such as norbornene, dicyclolopentane, decahydronaphthalene, and those having a skeleton represented by the following general formula.

（式中、Ｘは二価の有機基を示す。）

(In the formula, X represents a divalent organic group.)

The component (A) of the present invention has a divalent group having a group other than the group defined as R ¹ in the R ¹ part in the general formula (1), for example, a skeleton such as ethane, propane, butane, hexane, etc. A polyoxazole precursor having a chain aliphatic hydrocarbon residue or an aromatic group in the R ¹ portion can also be used. Further, together with such a component (A), a poly having a structure in which all R ¹ of the polyoxazole precursor represented by the general formula (1) of the present invention is replaced with an aromatic group or a chain aliphatic hydrocarbon group. An oxazole precursor can also be used in combination.

Specifically, R ² in the structure represented by the general formula (1) is diphenyl, diphenyl ether, diphenyl thioether, benzophenone, diphenylmethane, diphenylpropane, diphenylhexafluoropropane, diphenylsulfoxide, diphenylsulfone, biphenyl, benzene, etc. Although the tetravalent aromatic hydrocarbon residue which has the following skeleton is exemplified as a typical example, it is not limited thereto. The number of carbon atoms is preferably 6-30. Preferred groups are diphenylhexafluoropropane, diphenylisopropane, diphenyl ether, diphenyl sulfoxide, and biphenyl. It is also possible to incorporate two or more kinds of groups exemplified in the above as R ² if necessary.

R ³ in the structure represented by the general formula (1) represents a monovalent organic group. Among them, preferred organic groups include, for example, alkyl groups, aryl groups, groups constituting acetals or ketals, silyl groups, silyl ether groups, alkoxycarbonyl groups, alkoxyalkyl groups, alkylsilyl groups, and the like. It is not something. Among these, an alkoxycarbonyl group having 2 to 10 carbon atoms and an alkoxyalkyl group are more preferable. By having these groups at the molecular ends, it is possible to give moderate solubility to the aqueous alkali solution.

  In the present invention, the polyoxazole precursor can be produced by using a dicarboxylic acid represented by the following general formula (5) and a diamino compound represented by the following general formula (6) as a part of the raw material.

In General Formula (5), R ¹ represents the same organic group as R ¹ in General Formula (1).

In General Formula (6), R ² represents the same organic group as R ² in General Formula (1).

The polyoxazole precursor can be obtained, for example, by the following method. Halogenation of the dicarboxylic acid represented by the general formula (5) using a halogenating agent such as thionyl chloride in an organic solvent such as N-methylpyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, or dimethylsulfoxide. Thereafter, the reaction is carried out in the same organic solvent as described above in the presence of a suitable catalyst such as pyridine and the diamino compound represented by the general formula (6). The reaction solution is poured into a poor solvent such as water, methanol, ethanol, propyl alcohol, acetone, etc., crystallized, filtered and dried. The hydroxypolyamide thus obtained is again dissolved in the organic solvent, and an appropriate esterifying agent is allowed to act in the presence of an acid or basic catalyst as necessary, whereby the terminal carboxylic acid group is subjected to the above-mentioned. An organic group represented by R ³ in the general formula (1) can be introduced. Examples of the esterifying agent include various alcohols, various vinyl ethers, halogenated alkyls, trimethylsilyl chloride, halogenated methyl alkyl ethers, and halogenated ethyl alkyl ethers. The reaction solution is poured into a poor solvent such as water, methanol, ethanol, propyl alcohol, acetone, etc., crystallized, filtered and dried to obtain a polyoxazole precursor having the structural unit represented by the general formula (1). You can get a body.

  Further, in the present invention, the polybenzoxazole precursor passes through a dicarboxylic acid derivative obtained by reacting 1-hydroxybenzotriazole with a dicarboxylic acid as disclosed in, for example, JP-A-9-183848. It can be obtained by reacting this with dihydroxyamine.

In the polyoxazole precursor having the structure represented by the general formula (1) of the present invention, the substitution rate of the organic group represented by R ³ is 0.1% or more and 80% or less of the carboxylic acid in all polymer molecules. It is preferable to give an appropriate dissolution rate and exposure sensitivity to the composition of the present invention, and more preferably 1% or more and 50% or less. If it is less than this, the film loss in the unexposed area will increase, and if it is more than this, the development time may become longer. This substitution rate can be calculated from the integrated intensity ratio of the ¹ H-NMR spectrum. At this time, the amount of carboxylic acid is quantified based on the number of repeating units in all polymer molecules, and the number of repeating units is calculated based on the charging ratio at the time of polymer synthesis.

  In the polyoxazole precursor having the structure represented by the general formula (1) of the present invention, a part thereof may include a repeating unit other than the repeating unit in the structure represented by the general formula (1). Good. In this case, the ratio is preferably 50% or less in all repeating units.

  Although there is no restriction | limiting in particular in the molecular weight of the polyoxazole precursor of the said (A) component, Generally it is preferable that it is 3,000-200,000 by an average molecular weight, and 5000-100,000 are more preferable. Moreover, 1-4 are preferable and the dispersion degree which remove | divided the weight average molecular weight by the number average molecular weight has more preferable 1-3. The molecular weight can be measured by GPC (gel permeation chromatography) and calculated in terms of polystyrene.

  In the composition of the present invention, together with the polyoxazole precursor used as the component (A), a compound capable of generating an acid upon irradiation with actinic rays (hereinafter referred to as an acid generator) is used as the component (B). This amount is preferably 0.01 to 50 parts by weight and preferably 0.01 to 20 parts by weight with respect to 100 parts by weight of component (A) in order to improve sensitivity and resolution during exposure. It is more preferable that the content be 0.5 to 20 parts by weight.

  The acid generator (B) used in the present invention exhibits an acidity upon irradiation with actinic rays such as ultraviolet rays, and has an organic group that can be decomposed by acid catalysis as the component (C) and converted into a hydrogen atom. Conversion of a compound (also referred to as a “solubility conversion agent”), specifically, an action of eliminating a protecting group.

  Specific examples of such (B) component compounds include diarylsulfonium salts, triarylsulfonium salts, dialkylphenacylsulfonium salts, diaryliodonium salts, aryldiazonium salts, aromatic tetracarboxylic acid esters, aromatic sulfonic acids. Esters, nitrobenzyl esters, oxime sulfonates, aromatic N-oxyimide sulfonates, aromatic sulfamides, haloalkyl group-containing hydrocarbon compounds, haloalkyl group-containing heterocyclic compounds, naphthoquinone diazide-4-sulfonate esters, etc. Used. Such compounds can be used in combination of two or more as required, or in combination with other sensitizers. Of these, aromatic oxime sulfonates and aromatic N-oxyimide sulfonates are preferred because of their high sensitivity, and diaryl iodonium salts and triaryl sulfonium salts are preferred because they can be expected to have an appropriate dissolution inhibiting effect on the unexposed areas.

  The component (C) used in the present invention has an organic group that can be decomposed by acid catalysis and converted into a hydrogen atom. As a result, a dissolution inhibiting effect is expected in the unexposed area, and a dissolution promoting effect is expected in the exposed area, and an appropriate contrast can be expressed.

  The component (C) used in the present invention is not particularly limited in terms of its structure, but is preferably bonded to an aromatic ring in the molecule, and -OR (wherein R is decomposed by the action of an acid, a hydrogen atom And / or -COOR (wherein R represents a monovalent organic group that can be decomposed by the action of an acid and converted to a hydrogen atom). It is a compound which has group shown by these.

  As said (C) component, what has the structure shown by the following general formula (3) or (4) is excellent in a sensitivity and a resolution, and preferable. In the following general formula (3), a and b are each an integer of 0 or more, a + b is an integer of 1 or more, and preferably a + b is an integer of 10 or less. In the following general formula (4), a and b are each an integer of 0 or more, and preferably a + b is an integer of 10 or less.

  In general formula (3), X represents an organic group, R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom, and when there are a plurality of them, they may be the same or different. a and b are each an integer of 0 or more, and a + b represents an integer of 1 or more.

  In general formula (4), X ′ represents an organic group, R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom, and when there are a plurality of them, they may be the same or different. a and b each represent an integer of 0 or more.

  As the monovalent group that can be decomposed by the acid catalysis and converted into a hydrogen atom, for example, those constituting an acetal or ketal having the following structure are preferable.

（式中、Ｒ’、Ｒ”及びＲ'''は各々独立に炭素数５以下のアルキル基を示し、Ｘは炭素数３以上（好ましくは２０以下）の２価のアルキレン基（側鎖を有していてもよい）を示す。）

(Wherein R ′, R ″ and R ′ ″ each independently represents an alkyl group having 5 or less carbon atoms, and X represents a divalent alkylene group having 3 or more carbon atoms (preferably 20 or less) (with a side chain). It may have)

  Specific examples include a tetrahydropyranyl group, a tetrahydrofuranyl group, an alkyl-substituted tetrahydropyranyl group, an alkyl-substituted tetrahydrofuranyl group, an alkoxy-substituted tetrahydropyranyl group, and an alkoxy-substituted tetrahydrofuranyl group. However, it is not limited to these. The most preferred group is a tetrahydropyranyl group.

  Examples of the monovalent group that can be decomposed by the action of an acid and converted into a hydrogen atom include a monovalent alkoxyalkyl group, an alkylsilyl group, and an alkoxycarbonyl group. Although there is no restriction | limiting in particular in these, As a preferable carbon number, it is 2-8 in the case of an alkoxyalkyl group, 1-20 in the case of an alkylsilyl group, and 2-15 in the case of an alkoxycarbonyl group.

  Specifically, methoxymethyl group, ethoxymethyl group, isopropoxymethyl group, tert-butoxymethyl group, ethoxyethyl group, methylsilyl group, ethylsilyl group, tert-butyldimethylsilyl group, tert-butoxycarbonyl group and the like are typical. Although illustrated as an example, it is not limited to these. Preferred groups are a methoxymethyl group, a 1-ethoxymethyl group, a t-butyldimethylsilyl group, and a t-butoxycarbonyl group.

  A monovalent alkyl group may be used for R in the substituent represented by -COOR. Although there is no restriction | limiting in particular in these, As a preferable carbon number, it is 1-10.

  Specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, an amyl group, and the like are illustrated as typical examples, but are not limited thereto. Absent. Most preferred groups are an ethyl group, an isopropyl group, and a tert-butyl group.

  In the present invention, X or X ′ in the structure represented by the general formula (3) or (4) is specifically diphenyl, diphenyl ether, diphenylthioether, benzophenone, diphenylmethane, diphenylpropane, diphenylhexafluoropropane. , Aromatic hydrocarbon residues having a skeleton such as diphenyl sulfoxide, diphenyl sulfone, benzene, naphthalene and perylene, aliphatic hydrocarbon residues having a skeleton such as ethane, propane, butane, cyclobutane, cyclohexane and adamantane, or The thing which has the following structure is mentioned.

（式中、Ｙ、Ｙ’は炭素数１〜２０の有機基を示す。）

(In the formula, Y and Y ′ represent an organic group having 1 to 20 carbon atoms.)

（式中、Ｚ、Ｚ’はアルキル基あるいはアルキル置換または無置換のヘテロ原子を示す。）

(In the formula, Z and Z ′ represent an alkyl group or an alkyl-substituted or unsubstituted heteroatom.)

  The solubility converter (C) used in the present invention is preferably a compound represented by the following general formula or a compound having a repeating unit. In the case of a polymer, the molecular weight is preferably 1000 to 30000 in terms of weight average molecular weight.

（式中、Ｙ、Ｙ’は炭素数１〜２０の有機基を示し、Ｒは前記同様、酸酸触媒作用で分解し水素原子に変換し得る有機基を示す。いずれも同一分子に複数あるときは同じでも異なっていても良い。ｐは繰り返し単位を表す１以上の整数である。）

(In the formula, Y and Y ′ represent an organic group having 1 to 20 carbon atoms, and R represents an organic group that can be decomposed and converted into a hydrogen atom by acid acid catalysis as described above. Both are present in the same molecule. And may be the same or different, and p is an integer of 1 or more representing a repeating unit.)

  The amount of the component (C) is preferably 1 to 500 parts by weight with respect to 100 parts by weight of the component (A) when the component (C) is an oligomer or polymer from the viewpoint of sensitivity and film quality after curing. More preferably, it is 10 to 300 parts by weight. In other cases, the amount is preferably 1 to 50 parts by weight, more preferably 1 to 25 parts by weight with respect to 100 parts by weight of component (A).

  The positive photosensitive resin composition of the present invention can contain an organic silane compound, an aluminum chelate compound, or the like in order to enhance the adhesion of the cured film to the substrate. Examples of the organic silane compound include vinyltriethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, urea propyltriethoxysilane, methylphenylsilanediol, ethylphenylsilanediol, n- Propylphenylsilanediol, isopropylphenylsilanediol, n-butylsiphenylsilanediol, isobutylphenylsilanediol, tert-butylphenylsilanediol, diphenylsilanediol, ethylmethylphenylsilanol, n-propylmethylphenylsilanol, isopropylmethylphenylsilanol , N-butylmethylphenylsilanol, isobutylmethylphenylsilanol, tert-butylmethylphenylsilanol , Ethyl n-propylphenylsilanol, ethylisopropylphenylsilanol, n-butylethylphenylsilanol, isobutylethylphenylsilanol, tert-butylethylphenylsilanol, methyldiphenylsilanol, ethyldiphenylsilanol, n-propyldiphenylsilanol, isopropyldiphenylsilanol , N-butyldiphenylsilanol, isobutyldiphenylsilanol, tert-butyldiphenylsilanol, phenylsilanetriol, 1,4-bis (trihydroxysilyl) benzene, 1,4-bis (methyldihydroxysilyl) benzene, 1,4-bis (Ethyldihydroxysilyl) benzene, 1,4-bis (propyldihydroxysilyl) benzene, 1,4-bis (butyldi) Droxysilyl) benzene, 1,4-bis (dimethylhydroxysilyl) benzene, 1,4-bis (diethylhydroxysilyl) benzene, 1,4-bis (dipropyldroxysilyl) benzene, 1,4-bis (dibutylhydroxy) And silyl) benzene. Examples of the aluminum chelate compound include tris (acetylacetonate) aluminum, acetylacetate aluminum diisopropylate, and the like. When using these adhesion grant agents, 0.1-20 weight part is preferable with respect to 100 weight part of (A) component, and 0.5-10 weight part is more preferable.

  In addition, the positive photosensitive resin composition of the present invention can contain a phenol compound suitable for preparing solubility in an alkaline developer.

  As said phenol compound, the compound which contains 2-8 phenolic hydroxyl groups in a molecule | numerator can be used. For example, bis (2-hydroxyphenyl) methane, 2-hydroxyphenyl- (4-hydroxyphenyl) methane, 3,3′-methylenebis (2-hydroxy-5-methylbenzenemethanol), 2,2′-methylenebis (4 -Methylphenol), bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane, tris (2-hydroxyphenyl) methane, tris (4-hydroxyphenyl) methane, bis (2-hydroxyphenyl)-(4-hydroxyphenyl) methane, bis (4-hydroxyphenyl)-(2-hydroxyphenyl) methane, 1,1,1-tris (2- Hydroxyphenyl) ethane, 1,1-bis (2-hydroxyphenyl) -1- (4- Loxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1- (2-hydroxyphenyl) ethane, 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1-bis (4- Hydroxyphenyl) -1- [4- {1- (4-hydroxyphenyl) -1-methylethyl} phenyl] ethane, 1,1-bis (2-hydroxyphenyl) -1-phenylethane, bis (4-hydroxy Phenyl) -phenylmethane, bis (2-hydroxyphenyl) -phenylmethane, 4,4′-dihydroxy-3,3′-dimethyl-biphenyl, and the like.

  In order to improve the mechanical properties of the cured film, the positive photosensitive resin composition in the present invention may be added with a crosslinking agent capable of reacting with a carboxylic acid or a hydroxyl group in the polymer when cured. Examples of these include compounds represented by the following general formula.

（式中、Ｍは炭素数１〜２０の有機基を示し、Ｒは水素原子あるいは硬化時の熱で分解し水素原子に変換し得る有機基を示す。いずれも同一分子に複数あるときは同じでも異なっていても良い。ｎは２以上の整数である。）

(In the formula, M represents an organic group having 1 to 20 carbon atoms, and R represents a hydrogen atom or an organic group that can be decomposed by heat at the time of curing to be converted to a hydrogen atom. However, n may be different, and n is an integer of 2 or more.)

  When using this crosslinking agent, 0.1-20 weight part is preferable with respect to 100 weight part of (A) component, and 0.5-10 weight part is more preferable.

  In addition, the positive photosensitive resin composition of the present invention may be added with a suitable surfactant or leveling agent in order to prevent coatability, for example, striation (film thickness unevenness) or improve developability. can do. Examples of such a surfactant or leveling agent include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, and the like. Megafax F171 is a commercially available product. , F173, R-08 (Dainippon Ink Chemical Co., Ltd. product name), Florard FC430, FC431 (Sumitomo 3M Co., Ltd. product name), Organosiloxane polymer KP341, KBM303, KBM403, KBM803 (Product made by Shin-Etsu Chemical Co., Ltd.) Name).

  Furthermore, the positive photosensitive resin composition of the present invention can be blended with a storage stabilizer, a dissolution inhibitor and the like, if necessary.

  In the present invention, the components of the positive photosensitive resin composition can be dissolved in a solvent and used in the form of a varnish. As the solvent, N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, dimethyl sulfoxide, 2-methoxyethanol, 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 acetate, cyclohexanone, cyclopentanone, tetrahydrofuran, etc. May be. Although there is no restriction | limiting in particular in the quantity of a solvent, Generally, it uses so that the ratio of the solvent in a composition may be 40 to 75 weight%.

  In the method for producing a pattern using the positive photosensitive resin composition of the present invention, the composition is first applied to a suitable support such as a silicon wafer, a ceramic, an aluminum substrate and the like. Examples of the coating method include spin coating using a spinner, spray coating using a spray coater, dipping, printing, and roll coating. Next, preferably after pre-baking at 60 to 140 ° C. for 30 seconds to 10 minutes to dry the coating film, a desired pattern shape can be irradiated with radiation or actinic radiation. As the actinic ray, radiation such as X-rays, electron beams, ultraviolet rays, visible rays, and actinic rays can be used, but those having a wavelength of 200 to 500 nm are preferable. Monochromatic light such as g-line or i-line can also be used. Next, it is preferable to heat at 50 to 150 ° C. for 30 seconds to 10 minutes to diffuse the acid generated on the surface layer of the irradiated portion to the bottom. Next, the pattern can be obtained by developing and dissolving and removing the irradiated portion.

  Developers include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia, primary amines such as ethylamine and n-propylamine, diethylamine, and di-n-propylamine. Secondary amines such as, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, etc. An alkaline aqueous solution and an aqueous solution to which an appropriate amount of a water-soluble organic solvent or a surfactant is added can be preferably used.

  As a developing method, methods such as spraying, paddle, dipping, and ultrasonic waves are possible. Next, the pattern formed by development can be rinsed. Distilled water can be used as the rinse liquid. Next, heat treatment can be performed to obtain a final pattern rich in heat resistance. The heating temperature is generally 150 to 450 ° C.

  The photosensitive resin composition of the present invention can be used for electronic components such as semiconductor devices and multilayer wiring boards. Specifically, surface protective films and interlayer insulating films of semiconductor devices, interlayer insulating films of multilayer wiring boards It can be used for forming. The semiconductor device of the present invention is not particularly limited except that it has a surface protective film and an interlayer insulating film formed using the composition, and can have various structures.

  An example of the semiconductor device manufacturing process of the present invention will be described below. FIG. 1 is a manufacturing process diagram of a semiconductor device having a multilayer wiring structure. In the figure, a semiconductor substrate 1 such as a Si substrate having circuit elements is covered with a protective film 2 such as a silicon oxide film except for a predetermined portion of the circuit elements, and a first conductor layer is formed on the exposed circuit elements. ing. An interlayer insulating film layer 4 is formed on the semiconductor substrate by spin coating or the like (first step).

  Next, a photosensitive resin layer 5 such as chlorinated rubber or phenol novolac is formed on the interlayer insulating film layer 4 by spin coating, and a predetermined portion of the interlayer insulating film layer 4 is exposed by a known photolithography technique. Thus, a window 6A is provided (second step). The interlayer insulating film layer 4 of the window 6A is selectively etched by dry etching means using a gas such as oxygen or carbon tetrafluoride to open the window 6B. Next, the photosensitive resin layer 5 is completely removed using an etching solution that corrodes only the photosensitive resin layer 5 without corroding the first conductor layer 3 exposed from the window 6B (third step).

  Furthermore, the second conductor layer 7 is formed using a known photolithography technique, and the electrical connection with the first conductor layer 3 is completely performed (fourth step). When a multilayer wiring structure having three or more layers is formed, each layer can be formed by repeating the above steps.

  Next, the surface protective film layer 8 is formed. In the example of this figure, the surface protective film layer 8 is applied with the photosensitive resin composition by a spin coat method and dried, and light is irradiated from above a mask on which a pattern for forming a window 6C is formed at a predetermined portion. Thereafter, development is performed with an alkaline aqueous solution to form a pattern, and heating is performed (fifth step). The surface protective film layer 8 protects the conductor layer from external stress, α rays, etc., and the obtained semiconductor device is excellent in reliability. In the above example, the interlayer insulating film layer can be formed using the photosensitive resin composition of the present invention.

  Hereinafter, the present invention will be described in more detail based on examples. In addition, this invention is not limited to the following Example.

Synthesis Example 1 Synthesis of Polybenzoxazole Precursor In a 0.5 liter flask equipped with a stirrer and a thermometer, 10.32 g of cyclohexane-1,4-dicarboxylic acid and 90 g of N-methylpyrrolidone were charged. After cooling the flask to 5 ° C., 12.64 g of thionyl chloride was added dropwise and reacted for 30 minutes to obtain a dichloride solution of cyclohexane-1,4-dicarboxylic acid. Next, 87.5 g of N-methylpyrrolidone was charged into a 0.5 liter flask equipped with a stirrer and a thermometer, and 18.30 g of bis (3-amino-4-hydroxyphenyl) hexafluoropropane was added and stirred. After dissolution, 8.53 g of pyridine was added and a solution of dichloride of cyclohexane-1,4-dicarboxylic acid was added dropwise over 30 minutes while maintaining the temperature at 0 to 5 ° C., and stirring was continued for 30 minutes. The solution was poured into 3 liters of water, and the precipitate was collected, washed three times with pure water, and then dried under reduced pressure to obtain polyhydroxyamide (hereinafter referred to as polymer I). The weight average molecular weight calculated | required by standard polystyrene conversion of the polymer I was 14580, and dispersion degree was 1.6. Next, in a 0.5 liter flask equipped with a stirrer and a thermometer, 20 g of polymer I and 100 g of N-methylpyrrolidone were charged and dissolved by stirring, and then the temperature was kept at 0 to 5 ° C. After 0.4 g of methyl ethyl ether was added dropwise and 0.4 g of triethylamine was further added dropwise, stirring was continued for 30 minutes. The solution was poured into 2 liters of water, and the precipitate was collected, washed with pure water three times, and then dried under reduced pressure to obtain polyhydroxyamide having an ethoxymethyl group introduced at the terminal (hereinafter referred to as polymer II). .

Synthesis example 2
In a 0.5 liter flask equipped with a stirrer and a thermometer, 20 g of polymer I and 100 g of N-methylpyrrolidone were charged and dissolved by stirring. Then, while maintaining the temperature at 0 to 5 ° C., 3,4- 0.4 g of dihydro-2H-pyran was added dropwise, and further 0.1 g of 12N hydrochloric acid was added dropwise, and stirring was continued for 30 minutes. The solution was poured into 2 liters of water, and the precipitate was collected, washed with pure water three times, and then dried under reduced pressure to obtain polyhydroxyamide in which a tetrahydropyranyl group was selectively introduced into a terminal carboxyl group (hereinafter referred to as “hydroxyhydroxyamide”). And polymer III).

Synthesis example 3
The synthesis was performed in the same manner except that the dicarboxylic acid used in Synthesis Example 1 was terephthalic acid. The resulting polymer is referred to as Polymer IV.

Photosensitivity characteristic evaluation The predetermined amount shown in Table 1 for the acid generator (component (B)), the solubility converter (C) component, and, if necessary, the sensitizer with respect to 100 parts by weight of the polybenzoxazole precursor. And dissolved in γ-butyrolactone. The chemical formulas of the components (B) (DIAS, DPI), (C) components (C1 to C8), and sensitizer (DMEA) in the composition of Table 1 are as shown in [Chemical Formula 16].

  The solution was spin-coated on a silicon wafer to form a coating film having a dry film thickness of 3 to 10 μm, and then i-line (365 nm) exposure was performed using an ultrahigh pressure mercury lamp through an interference filter. After exposure, heat at 120 ° C. for 3 minutes, develop with a 2.38% aqueous solution of tetramethylammonium hydroxide until the exposed silicon wafer is exposed, then rinse with water to obtain the minimum exposure required for pattern formation. The resolution was determined. The results are shown in Table 2.

In the above results, the sensitivity was as high as about 200 mJ / cm ² regardless of the combination of the component (B) and the component (C), and the post-development residual film ratio was as high as 85% or more. Further, the difference in dissolution rate between the unexposed area and the exposed area was large enough for pattern formation.

Comparative Example 1
In Example 1, instead of the polymer II, the polymer IV which does not have a group having an aliphatic cyclic structure was used to evaluate the photosensitive characteristics in the same manner. As a result, the residual film ratio after development was 42%, the exposure amount was 580 mJ / cm ² , and the minimum processing dimension was 30 μm. The resolution was lowered due to swelling of the unexposed area, and a desired pattern could not be formed.

Comparative Example 2
In Example 1, the photosensitive characteristics were evaluated in the same manner using isophthalic acid having no protective group introduced as component (C). As a result, the difference in dissolution rate between the unexposed area and the exposed area was insufficient, and a good pattern with a developed film remaining ratio of 61% and a resolution of 30 μm could not be obtained at an exposure amount of 880 mJ / cm ² .

Comparative Example 3
In Example 1, the photosensitive characteristics were evaluated in the same manner without adding the component (B). As a result, no pattern was obtained.

Comparative Example 4
In Example 1, the photosensitive characteristics were evaluated in the same manner without adding the component (C). As a result, the difference in dissolution rate between the unexposed area and the exposed area was insufficient, and a good pattern with a residual film ratio after development of 54% and a resolution of 30 μm could not be obtained at an exposure amount of 1 J / cm ² .

  As described above, since the positive photosensitive resin composition of the present invention has high sensitivity and high mechanical strength after thermosetting, it is suitable for a surface protective film and an interlayer insulating film.

It is a manufacturing process figure of the semiconductor device of a multilayer wiring structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor substrate 2 Protective film 3 1st conductor layer 4 Interlayer insulating film layer 5 Photosensitive resin layer 6A, 6B, 6C Window 7 2nd conductor layer 8 Surface protective film layer

Claims (7)

(A) A polyoxazole precursor having an organic group having an aliphatic cyclic structure in the main chain , the following general formula (1)

(Wherein R ¹ represents the following general formula (2)

(Wherein n represents an integer of 0 to 10) or an adamantane residue, R ² is a tetravalent organic group, R ³ is a monovalent organic group, and there are a plurality of them. The cases may be the same or different, and n represents an integer indicating the number of repetitions. And a polyoxazole precursor represented by:
(B) a compound that generates an acid upon irradiation with actinic rays;
(C) A positive photosensitive resin composition comprising an organic group-containing compound that can be decomposed by acid catalysis and converted into a hydrogen atom. The monovalent organic group R ³ is at least one selected from the group consisting of an alkyl group, an aryl group, an acetal or a ketal group, a silyl group, a silyl ether group, an alkoxycarbonyl group, an alkoxyalkyl group, and an alkylsilyl group. The positive photosensitive resin composition according to claim 1 , wherein The component (C) is bonded to an aromatic ring in the molecule and is represented by -OR (wherein R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom). And / or -COOR (wherein R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom). Or the positive photosensitive resin composition of 2. The component (C) is represented by the following general formula (3)

(In the formula, X represents an organic group, R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom, and when there are a plurality of them, they may be the same or different. Each is an integer of 0 or more, and a + b represents an integer of 1 or more.)
The positive photosensitive resin composition according to any one of claims 1 to 3, characterized in that in a compound represented by. The component (C) is represented by the following general formula (4)

(In the formula, X ′ represents an organic group, R represents a monovalent organic group that can be decomposed by the action of an acid and converted into a hydrogen atom, and when there are a plurality of them, they may be the same or different. A, b Each represents an integer of 0 or more.)
The positive photosensitive resin composition according to any one of claims 1 to 3, characterized in that a compound having a repeating unit represented by in. Applying the positive photosensitive resin composition according to any one of claims 1 to 5 on a support substrate and drying to obtain a positive photosensitive resin film; and A step of exposing, a step of heating the positive photosensitive resin film after the exposure, a step of developing the positive photosensitive resin film after the heating using an alkaline aqueous solution, and the positive photosensitive property after the development. method of forming a pattern which comprises a step of heat treating the resin film. It is an electronic component which has an electronic device which has the layer of the pattern obtained by the formation method of Claim 6 , Comprising: The layer of the said pattern in the said electronic device is an interlayer insulation film layer and / or a surface protective film layer An electronic component characterized by being provided as:

Images