JP2008231174A - Film-forming composition, insulating film and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film-forming composition which can form a film having high heat resistance, high mechanical strength, a low dielectric constant, and good storage stability with time, an insulating film obtained by using the above film-forming composition, and an electronic device having the insulating film. <P>SOLUTION: The film-forming composition comprises a compound represented by formula (1) (wherein A is an ester bond or an amide bond; B is an n<SB>1</SB>-valent organic group; R<SP>1</SP>is hydrogen or a monovalent substituent; R<SP>2</SP>is hydrogen or a monovalent organic group; n<SB>1</SB>is an integer of 1-6; n<SB>2</SB>is an integer of 0-4: n<SB>3</SB>is an integer of 1-5; and n<SB>2</SB>+n<SB>3</SB>=5) and a compound having a cage structure, the insulating film is obtained by using the above film-forming composition, and the electronic device has the above insulating film. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a film forming composition, an insulating film obtained using the composition, and an electronic device having the same.

In recent years, in the field of electronic materials, with the progress of higher integration, more functions, and higher performance, circuit resistance and capacitor capacity between wirings have increased, leading to an increase in power consumption and delay time. In particular, an increase in delay time is a major factor in reducing the signal speed of the device and the occurrence of crosstalk. Therefore, in order to reduce the delay time and speed up the device, it is necessary to reduce parasitic resistance and parasitic capacitance. It has been. As a specific measure for reducing this parasitic capacitance, an attempt has been made to cover the periphery of the wiring with a low dielectric interlayer insulating film. Further, the interlayer insulating film is required to have excellent heat resistance that can withstand post-processes such as a thin film formation process, chip connection, and pinning when manufacturing a mounting substrate, and chemical resistance that can withstand a wet process. Furthermore, in recent years, low resistance Cu wiring is being introduced from Al wiring, and along with this, planarization by CMP (Chemical Mechanical Polishing) has become common, and high mechanical strength that can withstand this process is high. It has been demanded.
As organic polymer-based interlayer insulating films, polybenzoxazole, polyimide, polyarylene (ether) and the like have been disclosed for a long time. However, in order to realize a high-speed device, a material having a lower dielectric constant is desired. When a heteroatom such as oxygen, nitrogen or sulfur or an aromatic hydrocarbon unit is introduced into the polymer molecule as in this material, the dielectric constant increases due to high molar polarization or the dielectric constant over time due to moisture absorption. Improvements were necessary because of the increase in the rate and problems that impair the reliability of the electronic device.
On the other hand, a polymer composed of saturated hydrocarbons has an advantage that it exhibits a lower dielectric constant because it has a smaller molar polarization than a polymer composed of heteroatom-containing units or aromatic hydrocarbon units. However, highly flexible hydrocarbons such as polyethylene, for example, have insufficient heat resistance and cannot be used for electronic device applications.

  A polymer in which adamantane or diamantane, which is a saturated hydrocarbon having a rigid cage structure, is introduced into the molecule is disclosed, and it is disclosed that the polymer has a low dielectric constant (Patent Document 1). Most of these materials are designed to introduce vacancies in the film in order to aim for a low dielectric constant. For this reason, there are known problems such as a decrease in heat resistance and mechanical strength, or water adsorbing in the pores, and these problems have been problems to be solved.

JP 2004-504455 A

  The object of the present invention is obtained by using a film-forming composition capable of forming a film having high heat resistance, high mechanical strength, low dielectric constant, and good storage stability, and the film-forming composition. And an electronic device having the insulating film.

As a result of intensive studies, the present inventors have found that the above problems can be solved by the following configurations <1> and <8> to <10>. It is shown below with <2>-<7> which are preferable embodiments.
<1> A film-forming composition comprising a compound represented by the following formula (1) and a compound having a cage structure,

（式（１）中、Ａはエステル結合又はアミド結合を表し、Ｂはｎ₁価の有機基を表し、Ｒ¹は水素原子又は一価の置換基を表し、Ｒ²は水素原子又は一価の有機基を表し、ｎ₁は１から６までの整数を表し、ｎ₂は０から４までの整数を表し、ｎ₃は１から５までの整数を表し、ｎ₂＋ｎ₃＝５を満たす。）
＜２＞ カゴ型構造を有する化合物が、カゴ型構造を有する重合体である上記＜１＞に記載の膜形成用組成物、
＜３＞ カゴ型構造を有する重合体が、カゴ型構造を有するモノマーの重合体である上記＜２＞に記載の膜形成用組成物、
＜４＞ カゴ型構造を有する重合体が、カゴ型構造を有するモノマーをラジカル開始剤存在下又は遷移金属触媒存在下で重合して得られたものである上記＜３＞に記載の膜形成用組成物、
＜５＞ カゴ型構造を有するモノマーが、重合可能な炭素−炭素二重結合及び炭素−炭素三重結合のうちの少なくともいずれかを有する上記＜３＞に記載の膜形成用組成物、
＜６＞ カゴ型構造が、アダマンタン、ビアダマンタン、ジアマンタン、トリアマンタン及びテトラマンタンよりなる群から選択される構造である上記＜１＞〜＜４＞のいずれか１つに記載の膜形成用組成物、
＜７＞ カゴ型構造を有するモノマーが、下記式（２）〜（７）で表されるモノマーよりなる群から選択されるモノマーである上記＜３＞に記載の膜形成用組成物、

(In Formula (1), A represents an ester bond or an amide bond, B represents an n ₁ -valent organic group, R ¹ represents a hydrogen atom or a monovalent substituent, and R ² represents a hydrogen atom or a monovalent group. N ₁ represents an integer from 1 to 6, n ₂ represents an integer from 0 to 4, n ₃ represents an integer from 1 to 5, and satisfies n ₂ + n ₃ = 5 .)
<2> The film-forming composition according to <1>, wherein the compound having a cage structure is a polymer having a cage structure,
<3> The film-forming composition according to <2>, wherein the polymer having a cage structure is a polymer of a monomer having a cage structure,
<4> The film-forming film according to <3>, wherein the polymer having a cage structure is obtained by polymerizing a monomer having a cage structure in the presence of a radical initiator or a transition metal catalyst. Composition,
<5> The film-forming composition according to <3>, wherein the monomer having a cage structure has at least one of a polymerizable carbon-carbon double bond and carbon-carbon triple bond,
<6> The film-forming composition according to any one of <1> to <4>, wherein the cage structure is a structure selected from the group consisting of adamantane, biadamantane, diamantane, triamantane, and tetramantane. object,
<7> The film-forming composition according to <3>, wherein the monomer having a cage structure is a monomer selected from the group consisting of monomers represented by the following formulas (2) to (7):

（式（２）〜（７）中、Ｘ₁〜Ｘ₈はそれぞれ独立に、水素原子、アルキル基、アルケニル基、アルキニル基、アリール基、シリル基、アシル基、アルコキシカルボニル基又はカルバモイル基等を表し、Ｙ₁〜Ｙ₈はそれぞれ独立に、ハロゲン原子、アルキル基、アリール基又はシリル基を表し、ｍ₁、ｍ₅は１〜１６の整数を表し、ｎ₁、ｎ₅は０〜１５の整数を表し、ｍ₂、ｍ₃、ｍ₆、ｍ₇はそれぞれ独立に１〜１５の整数を表し、ｎ₂、n₃、ｎ₆、ｎ₇は０〜１４の整数を表し、ｍ₄、ｍ₈は１〜２０の整数を表し、ｎ₄、ｎ₈は０〜１９の整数を表す。）
＜８＞ 上記＜１＞〜＜７＞のいずれか１つに記載の絶縁膜形成用組成物、
＜９＞ 上記＜８＞に記載の絶縁膜形成用組成物を用いて得られる絶縁膜、
＜１０＞ 上記＜９＞に記載の絶縁膜を有する電子デバイス。

(In formulas (2) to (7), X _{1 to} X ₈ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a silyl group, an acyl group, an alkoxycarbonyl group or a carbamoyl group. Y _{1 to} Y ₈ each independently represents a halogen atom, an alkyl group, an aryl group or a silyl group, m ₁ and m ₅ represent an integer of ₁ to 16, and n ₁ and n ₅ represent 0 to 15 It represents an _{integer, m 2, m 3, m} 6, m 7 each independently represents an integer of _{1~15, n 2, n 3,} n 6, n 7 is an integer of 0 to 14, m _4, m ₈ represents an integer of 1 to 20, and n ₄ and n ₈ represent an integer of 0 to 19.)
<8> The composition for forming an insulating film according to any one of <1> to <7> above,
<9> An insulating film obtained using the insulating film forming composition according to <8>,
<10> An electronic device having the insulating film according to <9>.

  According to the present invention, a film-forming composition capable of forming a film having high heat resistance, high mechanical strength, low dielectric constant, and good storage stability, and obtained using the film-forming composition. And an electronic device having the insulating film can be provided.

Hereinafter, the present invention will be described in detail.
The film forming composition of the present invention comprises a compound represented by the following formula (1) and a compound having a cage structure.

（式（１）中、Ａはエステル結合又はアミド結合を表し、Ｂはｎ₁価の有機基を表し、Ｒ¹は水素原子又は一価の置換基を表し、Ｒ²は水素原子又は一価の有機基を表し、ｎ₁は１から６までの整数を表し、ｎ₂は０から４までの整数を表し、ｎ₃は１から５までの整数を表し、ｎ₂＋ｎ₃＝５を満たす。）

(In Formula (1), A represents an ester bond or an amide bond, B represents an n ₁ -valent organic group, R ¹ represents a hydrogen atom or a monovalent substituent, and R ² represents a hydrogen atom or a monovalent group. N ₁ represents an integer from 1 to 6, n ₂ represents an integer from 0 to 4, n ₃ represents an integer from 1 to 5, and satisfies n ₂ + n ₃ = 5 .)

(Compound represented by the formula (1))
The film-forming composition of the present invention contains a compound represented by the following formula (1) (hereinafter also referred to as “compound (A)”).
The film forming composition of the present invention can form a film excellent in heat resistance and mechanical strength by containing the compound represented by the formula (1).
The compound represented by the following formula (1) in the film-forming composition of the present invention may be used alone or in combination of two or more.
A in the formula (1) is an ester bond or an amide bond. The ester bond may be —O—CO— or —CO—O—, and the amide bond may be either —NR—CO— or —CO—NR—. R in the amide bond represents a hydrogen atom or a monovalent organic group, and is preferably a hydrogen atom. Examples of the monovalent organic group in R include a monovalent organic group in R ² described later. When n ₁ is 2 or more, that is, when R is 2 or more, the 2 or more Rs may be the same or different.

B in the formula (1) is an n ₁ valent organic group, and n ₁ hydrogen atoms are substituted from an organic group having a cage structure or a cyclic structure, an ethynyl group, an ethenyl group, or an aromatic ring of an aromatic compound. The residue is preferably an organic group having a cage structure, or more preferably a residue obtained by removing n ₁ hydrogen atoms from the aromatic ring of the aromatic compound, and the aromatic ring of the aromatic compound. More preferably, it is a residue obtained by removing n ₁ hydrogen atoms from. Specific examples of the aromatic compound are shown below.

  Among these, the aromatic compound is preferably the following compound,

  The following compounds are more preferable.

R ¹ in the formula (1) represents a hydrogen atom or a monovalent substituent, preferably a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, halogen atom, nitro group, hydroxyl group or carboxyl group. Can be mentioned. A hydrogen atom, an alkyl group, an alkenyl group or an aryl group is more preferred, a hydrogen atom, an alkyl group or an aryl group is more preferred, and a hydrogen atom is particularly preferred.

R ² in the formula (1) represents a hydrogen atom or a monovalent organic group, and preferred examples include a hydrogen atom, an alkyl group, and an aryl group. A hydrogen atom or an aryl group is more preferable, and a hydrogen atom is particularly preferable.

N < ₁ > in the said Formula (1) represents the integer of 1-6, Preferably it is 2-6, Most preferably, it is 3-6.
N ₂ in the formula (1) represents an integer of 0 to 4, preferably 1 to 4, particularly preferably 2 to 4.
N ₃ in the formula (1) represents an integer of 1 to 5, preferably 1 to 4, particularly preferably 1 to 3.

  As for the molecular weight of the compound (A), the weight average molecular weight (Mw) is preferably 300 or more. If it is 300 or more, since the volatility is low, the concentration in the film does not decrease, and the target function is sufficiently developed.

  Specific examples of the compound (A) that can be used in the present invention are described below, but the present invention is not limited thereto.

The amount of the compound (A) added in the film-forming composition of the present invention is preferably 0.1 to 60% by weight, more preferably 1 to 50% by weight, particularly preferably the solid content of the film-forming composition. Preferably it is 5-45 weight%. Here, the solid content corresponds to all components constituting the film obtained using this composition.
The weight ratio of the compound (A) to the compound having a cage structure (compound (B)) described later in the film-forming composition of the present invention is preferably compound (A): compound (B) = 0. .1 to 90: 99.9 to 10, more preferably 1 to 70:99 to 30, and particularly preferably 5 to 50:95 to 50.

(Compound having a cage structure)
The film-forming composition of the present invention contains a compound having a cage structure (hereinafter also referred to as “compound (B) having a cage structure” or “compound (B)”).
The “cage structure” described in the present invention is such that the volume is determined by a plurality of rings formed of covalently bonded atoms, and a point located within the volume cannot be separated from the volume without passing through the ring. Refers to a molecule. For example, an adamantane structure is considered a cage structure. In contrast, a cyclic structure having a single bridge, such as norbornane (bicyclo [2.2.1] heptane), is not considered a cage structure because the ring of the single bridged cyclic compound does not define volume. .
By containing the compound having a cage structure, the film forming composition of the present invention can provide a film having excellent heat resistance and mechanical strength and having a low dielectric constant.
The film-forming composition of the present invention is a film having high heat resistance, high mechanical strength, and low dielectric constant by using a compound represented by the formula (1) and a compound having a cage structure in combination. In addition, it is excellent in storage stability over time of the resulting film.

  The cage structure in the present invention may contain either a saturated or unsaturated bond and may contain a heteroatom such as oxygen, nitrogen or sulfur, but a saturated hydrocarbon is preferred from the viewpoint of a low dielectric constant.

  The cage structure in the present invention is preferably adamantane, biadamantane, diamantane, triamantane, tetramantane or dodecahedrane, more preferably adamantane, biadamantane or diamantane, particularly preferably in terms of low dielectric constant. Biadamantane or diamantane.

  The cage structure in the present invention may have one or more substituents, and examples of the substituent include a halogen atom (a fluorine atom, a chloro atom, a bromine atom or an iodine atom), a carbon number of 1 to 10. Linear, branched or cyclic alkyl groups (methyl, t-butyl, cyclopentyl, cyclohexyl, etc.), alkenyl groups having 2 to 10 carbon atoms (vinyl, propenyl, etc.), alkynyl groups having 2 to 10 carbon atoms (ethynyl, phenyl) Ethynyl, etc.), C6-C20 aryl groups (phenyl, 1-naphthyl, 2-naphthyl, etc.), C2-C10 acyl groups (benzoyl, etc.), C2-C10 alkoxycarbonyl groups (methoxycarbonyl) Etc.), C 1-10 carbamoyl groups (N, N-diethylcarbamoyl etc.), C 6-20 aryloxy groups (phenoxy etc.), carbon 6-20 arylsulfonyl group (phenylsulfonyl, etc.), a nitro group, a cyano group, a silyl group (triethoxysilyl, methyldiethoxysilyl, trivinylsilyl or the like) and the like.

  The cage structure in the present invention is preferably a divalent to tetravalent group. At this time, the group bonded to the cage structure may be a monovalent or higher valent substituent or a divalent or higher linking group. The cage structure is more preferably a divalent or trivalent group, and particularly preferably a divalent group.

  The compound having a cage structure of the present invention is preferably a polymer of a monomer having a cage structure. Here, the term “monomer” refers to a monomer that is polymerized to be a dimer or higher polymer. The polymer may be a homopolymer or a copolymer.

  The polymerization reaction of the monomer is caused by the polymerizable group substituted for the monomer. Here, the polymerizable group refers to a reactive substituent that polymerizes the monomer. The polymerization reaction may be any polymerization reaction, and examples thereof include radical polymerization, cationic polymerization, anionic polymerization, ring-opening polymerization, polycondensation, polyaddition, addition condensation, or transition metal catalyst polymerization.

The monomer polymerization reaction is preferably performed in the presence of a nonmetallic polymerization initiator. For example, a monomer having a polymerizable carbon-carbon double bond or carbon-carbon triple bond may be polymerized in the presence of a polymerization initiator that exhibits activity by generating free radicals such as carbon radicals and oxygen radicals by heating. it can.
As the polymerization initiator, an organic peroxide or an organic azo compound is preferably used, and an organic peroxide is particularly preferable.
Examples of the organic peroxide include ketone peroxides such as perhexa H, peroxyketals such as perhexa TMH, hydroperoxides such as perbutyl H-69, park mill D, perbutyl C, etc. Dialkyl peroxides such as perbutyl D, diacyl peroxides such as niper BW, peroxyesters such as perbutyl Z and perbutyl L, and peroxydicarbonates such as peroyl TCP are preferably used.
Examples of the organic azo compound include azonitrile compounds such as V-30, V-40, V-59, V-60, V-65, and V-70 that are commercially available from Wako Pure Chemical Industries, Ltd., VA-080. Azoamide compounds such as VA-085, VA-086, VF-096, VAm-110, VAm-111, cyclic azoamidine compounds such as VA-044, VA-061, and azoamidines such as V-50, VA-057 Compounds and the like are preferably used.

Only one polymerization initiator or a mixture of two or more polymerization initiators may be used.
The amount of the polymerization initiator used is preferably 0.001 to 2 mol, more preferably 0.01 to 1 mol, and particularly preferably 0.05 to 0.5 mol with respect to 1 mol of the monomer.

The polymerization reaction of the monomer is also preferably performed in the presence of a transition metal catalyst. For example, a monomer having a polymerizable carbon-carbon double bond or carbon-carbon triple bond is a Pd-based catalyst such as tetrakistriphenylphosphine palladium (Pd (PPh ₃ ) ₄ ), palladium acetate (Pd (OAc) ₂ ), Ziegler-Natta catalyst, Ni catalyst such as nickel acetyl acetonate, W-based catalyst such as WCl _6, Mo-based catalysts such as MoCl _5, Ta catalysts such as TaCl _5, Nb-based catalyst such as NbCl _5, Rh-based catalyst Polymerization is preferably performed using a Pt-based catalyst or the like.

Only one transition metal catalyst or a mixture of two or more transition metal catalysts may be used.
The amount of the transition metal catalyst used is preferably 0.001 to 2 mol, more preferably 0.01 to 1 mol, and particularly preferably 0.05 to 0.5 mol with respect to 1 mol of the monomer.

The cage structure in the present invention may be substituted as a pendant group in the polymer and may be a part of the polymer main chain, but a form that is a part of the polymer main chain is more preferable. Here, the form which is a part of the polymer main chain means that the polymer chain is cleaved when the cage compound is removed from the polymer. In this form, the cage structure is directly single-bonded or connected by an appropriate divalent linking group. Examples of the linking group include, for example, —C (R ¹¹ ) (R ¹² ) —, —C (R ¹³ ) ═C (R ¹⁴ ) —, —C≡C—, arylene group, —CO—, —O—. , —SO ₂ —, —N (R ¹⁵ ) —, —Si (R ¹⁶ ) (R ¹⁷ ) —, or a combination thereof. Here, R ^{11 to} R ¹⁷ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group or an aryl group. These linking groups may be substituted with a substituent, and for example, the above-described substituents are preferable examples.
Among these, more preferred linking groups are —C (R ¹¹ ) (R ¹² ) —, —CH═CH—, —C≡C—, arylene group, —O—, —Si (R ¹⁶ ) (R ¹⁷ ). - or a group formed by combining these groups, particularly preferred are, -C terms of low dielectric constant ^{(R 11) (R 12)} -, - is CH = CH-.

The compound having a cage structure that can be used in the present invention may be a low molecular compound or a high molecular compound (for example, a polymer (polymer)), but a preferable one is a polymer.
When the compound having a cage structure is a polymer, the weight average molecular weight is preferably 1,000 to 500,000, more preferably 5,000 to 200,000, and particularly preferably 10,000 to 100,000. It is. The polymer having a cage structure may be included in the coating liquid for forming an insulating film as a resin composition having a molecular weight distribution.
When the compound having a cage structure is a low molecular compound, the molecular weight is preferably 150 to 3,000, more preferably 200 to 2,000, and particularly preferably 220 to 1,000.

  The compound having a cage structure that can be used in the present invention is preferably a polymer of a monomer having a polymerizable carbon-carbon double bond or carbon-carbon triple bond. Furthermore, a polymer of a compound represented by the following formulas (2) to (7) is more preferable.

（式（２）〜（７）中、Ｘ₁〜Ｘ₈はそれぞれ独立に、水素原子、アルキル基、アルケニル基、アルキニル基、アリール基、シリル基、アシル基、アルコキシカルボニル基又はカルバモイル基等を表し、Ｙ₁〜Ｙ₈はそれぞれ独立に、ハロゲン原子、アルキル基、アリール基又はシリル基を表し、ｍ₁、ｍ₅は１〜１６の整数を表し、ｎ₁、ｎ₅は０〜１５の整数を表し、ｍ₂、ｍ₃、ｍ₆、ｍ₇はそれぞれ独立に１〜１５の整数を表し、ｎ₂、n₃、ｎ₆、ｎ₇は０〜１４の整数を表し、ｍ₄、ｍ₈は１〜２０の整数を表し、ｎ₄、ｎ₈は０〜１９の整数を表す。）

(In formulas (2) to (7), X _{1 to} X ₈ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a silyl group, an acyl group, an alkoxycarbonyl group or a carbamoyl group. Y _{1 to} Y ₈ each independently represents a halogen atom, an alkyl group, an aryl group or a silyl group, m ₁ and m ₅ represent an integer of ₁ to 16, and n ₁ and n ₅ represent 0 to 15 It represents an _{integer, m 2, m 3, m} 6, m 7 each independently represents an integer of _{1~15, n 2, n 3,} n 6, n 7 is an integer of 0 to 14, m _4, m ₈ represents an integer of 1 to 20, and n ₄ and n ₈ represent an integer of 0 to 19.)

In formulas (2) to (7), X _{1 to} X ₈ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, An aryl group having 6 to 20 carbon atoms, a silyl group having 0 to 20 carbon atoms, an acyl group having 2 to 10 carbon atoms, an alkoxycarbonyl having 2 to 10 carbon atoms, a carbamoyl group having 1 to 20 carbon atoms and the like are represented. Among these, Preferably a hydrogen atom, a C1-C10 alkyl group, a C6-C20 aryl group, a C0-C20 silyl group, a C2-C10 acyl group, C2-C10 An alkoxycarbonyl group and a carbamoyl group having 1 to 20 carbon atoms, more preferably a hydrogen atom and an aryl group having 6 to 20 carbon atoms, and particularly preferably a hydrogen atom.
Further, the above-mentioned group in X ₁ to X ₈ may have a substituent.
In formulas (2) to (7), Y _{1 to} Y ₈ are each independently a halogen atom (fluorine, chlorine, bromine, etc.), an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, or carbon. Represents a silyl group having 0 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms which may have a substituent and an aryl group having 6 to 20 carbon atoms, particularly preferably an alkyl group (methyl group). Etc.).
X _{1 to} X ₈ and Y _{1 to} Y ₈ may be further substituted with another substituent.
There is no restriction | limiting in particular as said substituent, What is necessary is just an organic group.

In formula (2) or formula (5), m ₁ and m ₅ each independently represents an integer of 1 to 16, preferably 1 to 4, more preferably 1 to 3, particularly preferably 2. is there.
In formula (2) or formula (5), n ₁ and n ₅ each independently represents an integer of 0 to 15, preferably 0 to 4, more preferably 0 or 1, particularly preferably 0. is there.
In formula (3) or formula (6), m ₂ , m ₃ , m ₆ and m ₇ each independently represents an integer of 1 to 15, preferably 1 to 4, more preferably 1 to 3. Particularly preferably 2.
In formula (3) or formula (6), n ₂ , n ₃ , n ₆ and n ₇ each independently represents an integer of 0 to 14, preferably 0 to 4, more preferably 0 or 1. Particularly preferably 0.
In formula (4) or formula (7), m ₄ and m ₈ each independently represents an integer of 1 to 20, preferably 1 to 4, more preferably 1 to 3, particularly preferably 2. is there.
In Formula (4) or Formula (7), n ₄ and n ₈ each independently represents an integer of 0 to 19, preferably 0 to 4, more preferably 0 or 1, particularly preferably 0. is there.

  The monomer having a cage structure that can be used in the present invention is preferably a compound represented by the formula (2), formula (3), formula (5) or formula (6), more preferably the formula (2) or a compound represented by formula (3), particularly preferably a compound represented by formula (3).

  Two or more compounds having a cage structure that can be used in the present invention may be used in combination, and two or more monomers having a cage structure that can be used in the present invention may be copolymerized. .

The compound having a cage structure preferably has sufficient solubility in an organic solvent. The solubility of the compound having a cage structure is preferably 3% by weight or more, more preferably 5% by weight or more, and particularly preferably 10% by weight or more with respect to cyclohexanone or anisole at 25 ° C.
The addition amount of the compound having a cage structure is preferably 1 to 20% by weight, more preferably 1 to 15% by weight, and particularly preferably 1 to 10% by weight with respect to the solid content of the film-forming composition.

  Examples of compounds having a cage structure that can be used in the present invention include polybenzoxazoles described in JP-A-11-322929, JP-A-2003-12802, and JP-A-2004-18593, and JP-A-2001. No. 2899, quinoline resin, JP-T 2003-530464, JP-T 2004-535497, JP-T 2004-504424, JP-T 2004-504455, JP-T 2005-501131, JP-A-2005-516382, JP-A-2005-514479, JP-A-2005-522528, JP-A-2000-100808, US Pat. No. 6,509,415, JP-A-11-214382 Publication, JP 2001-332542 A Polyadamantanes described in JP-A-2003-252982, JP-A-2003-292878, JP-A-2004-2787, JP-A-2004-67877, JP-A-2004-59444, JP-A-2003 Examples thereof include polyimides described in JP-A-2525292 and JP-A-2004-26850.

  Specific examples of the monomer having a cage structure that can be used in the present invention are described below, but the present invention is not limited thereto.

  Further, examples of the monomer having a cage structure that can be used in the present invention include those in which —C≡C— in the above specific examples is changed to —CH═CH—. The -CH = CH- may be either a cis type or a trans type.

As the solvent used in the polymerization reaction, any solvent may be used as long as the raw material monomer can be dissolved at a necessary concentration and does not adversely affect the characteristics of the film formed from the obtained polymer. . For example, alcohol solvents such as water, methanol, ethanol and propanol, alcohol solvents such as alcohol acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, acetophenone, ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, γ-butyrolactone, methyl benzoate Ester solvents such as dibutyl ether and anisole, toluene, xylene, mesitylene, 1,2,4,5-tetramethylbenzene, pentamethylbenzene, isopropylbenzene, 1,4-diisopropylbenzene, t- Butylbenzene, 1,4-di-t-butylbenzene, 1,3,5-triethylbenzene, 1,3,5-tri-t-butylbenzene, 4-t-butyl-orthoxylene, 1- Aromatic hydrocarbon solvents such as tilnaphthalene and 1,3,5-triisopropylbenzene, amide solvents such as N-methylpyrrolidinone and dimethylacetamide, carbon tetrachloride, dichloromethane, chloroform, 1,2-dichloroethane, chlorobenzene, Halogen solvents such as 1,2-dichlorobenzene and 1,2,4-trichlorobenzene and aliphatic hydrocarbon solvents such as hexane, heptane, octane and cyclohexane can be used.
Among these, more preferred solvents are acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, acetophenone, ethyl acetate, propylene glycol monomethyl ether acetate, γ-butyrolactone, anisole, tetrahydrofuran, toluene, xylene, mesitylene, 1, 2, 4, 5-tetramethylbenzene, isopropylbenzene, t-butylbenzene, 1,4-di-t-butylbenzene, 1,3,5-tri-t-butylbenzene, 4-t-butyl-orthoxylene, 1-methyl Naphthalene, 1,3,5-triisopropylbenzene, 1,2-dichloroethane, chlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, more preferably tetrahydrofuran, γ-butyrolactone, Nisole, toluene, xylene, mesitylene, isopropylbenzene, t-butylbenzene, 1,3,5-tri-t-butylbenzene, 1-methylnaphthalene, 1,3,5-triisopropylbenzene, 1,2-dichloroethane, Chlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, particularly preferably γ-butyrolactone, anisole, mesitylene, t-butylbenzene, 1,3,5-triisopropylbenzene, 1,2- Dichlorobenzene and 1,2,4-trichlorobenzene. These may be used alone or in admixture of two or more.
The concentration of the monomer in the reaction solution is preferably 1 to 50% by weight, more preferably 5 to 30% by weight, and particularly preferably 10 to 20% by weight.

Optimum conditions for the polymerization reaction in the present invention vary depending on the polymerization initiator, monomer, solvent type, concentration, and the like, but preferably the internal temperature is 0 ° C to 200 ° C, more preferably 50 ° C to 170 ° C, and particularly preferably 100. C. to 150.degree. C., preferably 1 to 50 hours, more preferably 2 to 20 hours, and particularly preferably 3 to 10 hours.
Moreover, in order to suppress the inactivation of the polymerization initiator by oxygen, it is preferable to make it react under inert gas atmosphere (for example, nitrogen, argon, etc.). The oxygen concentration during the reaction is preferably 100 ppm or less, more preferably 50 ppm or less, and particularly preferably 20 ppm or less.
The preferred range of the weight average molecular weight of the polymer obtained by polymerization is 1,000 to 500,000, more preferably 5,000 to 300,000, and particularly preferably 10,000 to 200,000.

For example, a compound having a cage structure is prepared by reacting with bromine in the presence or absence of an aluminum bromide catalyst using a commercially available diamantane as a raw material to introduce a bromine atom at a desired position, followed by aluminum bromide, aluminum chloride, chloride. It can be synthesized by conducting Friedel-Crafts reaction with vinyl bromide in the presence of Lewis acid such as iron, introducing 2,2-dibromoethyl group, and then dehydrobrating with strong base to convert to ethynyl group. it can. Specifically, it is synthesized according to the method described in Macromolecules., 1991, 24, 5266-5268, 1995, 28, 5554-5560, Journal of Organic Chemistry., 39, 2995-3003 (1974), etc. can do.
In addition, an alkyl group or a silyl group can be introduced by anionizing a hydrogen atom of a terminal acetylene group with butyllithium or the like and reacting this with an alkyl halide or a silyl halide.

  A polymer having a cage structure may be used alone or in admixture of two or more.

The coating solvent that can be used in the present invention is not particularly limited. For example, alcohol solvents such as methanol, ethanol, 2-propanol, 1-butanol, 2-ethoxymethanol, 3-methoxypropanol, and 1-methoxy-2-propanol are used. Solvent, Acetone, Acetylacetone, Methyl ethyl ketone, Methyl isobutyl ketone, 2-pentanone, 3-pentanone, 2-heptanone, 3-heptanone, cyclopentanone, cyclohexanone and other ketone solvents, ethyl acetate, propyl acetate, butyl acetate, isobutyl acetate Pentyl acetate, ethyl propionate, propyl propionate, butyl propionate, isobutyl propionate, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, γ-butyrolactone, etc. Ter solvents, ether solvents such as diisopropyl ether, dibutyl ether, ethyl propyl ether, anisole, phenetol, veratrol, aromatic hydrocarbon solvents such as mesitylene, ethylbenzene, diethylbenzene, propylbenzene, t-butylbenzene, N-methyl Examples include amide solvents such as pyrrolidinone and dimethylacetamide, and these may be used alone or in admixture of two or more.
More preferred coating solvents are 1-methoxy-2-propanol, propanol, acetylacetone, cyclohexanone, propylene glycol monomethyl ether acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolactone, anisole, mesitylene, t-butylbenzene, especially Preferred are 1-methoxy-2-propanol, cyclohexanone, propylene glycol monomethyl ether acetate, ethyl lactate, γ-butyrolactone, t-butylbenzene and anisole.

The film forming composition of the present invention preferably has a sufficiently low metal content as an impurity. The metal concentration of the film-forming composition can be measured with high sensitivity by the ICP-MS method. In that case, the metal content other than the transition metal is preferably 30 ppm or less, more preferably 3 ppm or less, particularly preferably 300 ppb or less. It is.
In addition, the transition metal has a high catalytic ability to promote oxidation, and from the viewpoint of increasing the dielectric constant of the film obtained in the present invention by an oxidation reaction in the prebaking and thermosetting processes, the content is preferably smaller. Preferably it is 10 ppm or less, More preferably, it is 1 ppm or less, Most preferably, it is 100 ppb or less.
The metal concentration of the film-forming composition can also be evaluated by performing total reflection X-ray fluorescence measurement on a film obtained using the film-forming composition of the present invention. When a W (tungsten) ray is used as an X-ray source, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pd can be observed as metal elements, each of which is 100 × 10 ¹⁰ atoms. · Cm ⁻² or less is preferable, 50 × 10 ¹⁰ atom · cm ⁻² or less is more preferable, and 10 × 10 ¹⁰ atom · cm ⁻² or less is particularly preferable. Further, Br which is halogen can be observed, and the residual amount is preferably 10,000 × 10 ¹⁰ atom · cm ⁻² or less, more preferably 1,000 × 10 ¹⁰ atom · cm ⁻² or less, and 400 × 10 ^10. Atom · cm ⁻² or less is particularly preferable. Further, although Cl can be observed as a halogen, the residual amount is preferably 100 × 10 ¹⁰ atom · cm ⁻² or less from the viewpoint of damaging the CVD apparatus, the etching apparatus, etc., and 50 × 10 ¹⁰ atom · cm ^−2. The following is more preferable, and 10 × 10 ¹⁰ atom · cm ⁻² or less is particularly preferable.

The film forming composition of the present invention may contain an organic solvent.
Although it does not specifically limit as an organic solvent, For example, alcohol solvents, such as methanol, ethanol, 2-propanol, 1-butanol, 2-ethoxymethanol, 3-methoxypropanol, 1-methoxy-2-propanol, acetone, acetylacetone, Ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, 2-pentanone, 3-pentanone, 2-heptanone, 3-heptanone, cyclopentanone, cyclohexanone, ethyl acetate, propyl acetate, butyl acetate, isobutyl acetate, pentyl acetate, propionic acid Esters such as ethyl, propyl propionate, butyl propionate, isobutyl propionate, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, γ-butyrolactone, diisopropyl Ether solvents such as pyr ether, dibutyl ether, ethyl propyl ether, anisole, phenetol, veratrol, aromatic hydrocarbon solvents such as mesitylene, ethylbenzene, diethylbenzene, propylbenzene, t-butylbenzene, N-methylpyrrolidinone, dimethylacetamide And amide solvents such as these may be used, and these may be used alone or in admixture of two or more.
More preferred organic solvents are 1-methoxy-2-propanol, propanol, acetylacetone, cyclohexanone, propylene glycol monomethyl ether acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolactone, anisole, mesitylene, t-butylbenzene, Particularly preferred are 1-methoxy-2-propanol, cyclohexanone, 2-heptanone, propylene glycol monomethyl ether acetate, ethyl lactate, γ-butyrolactone, t-butylbenzene and anisole.

The solid content concentration of the film-forming composition of the present invention is preferably 1 to 50% by weight, more preferably 2 to 15% by weight, and particularly preferably 3 to 10% by weight.
Here, the solid content corresponds to all components constituting the film obtained using this composition.
The polymer having a cage structure obtained in the present invention preferably has sufficient solubility in an organic solvent. The solubility of the polymer having a cage structure is preferably 3% by weight or more, more preferably 5% by weight or more, and particularly preferably 10% by weight or more with respect to cyclohexanone or anisole at 25 ° C.

  Furthermore, the composition for film formation of the present invention includes the above-described polymerization initiator and transition metal as long as the properties (heat resistance, dielectric constant, mechanical strength, coatability, adhesion, etc.) of the obtained insulating film are not impaired. You may add additives, such as radical generators, such as a catalyst, colloidal silica, surfactant, a silane coupling agent, and an adhesive agent.

  Any colloidal silica may be used in the film-forming composition of the present invention. For example, a dispersion in which high-purity silicic acid is dispersed in a hydrophilic organic solvent or water, preferably having an average particle size of 5 to 30 nm, more preferably 10 to 20 nm, and a solid content concentration of 5 to 40% by weight It is.

  Any surfactant may be used in the film-forming composition of the present invention, and examples thereof include nonionic surfactants, anionic surfactants, and cationic surfactants, and silicone-based surfactants. Surfactants, fluorine-containing surfactants, polyalkylene oxide surfactants, and acrylic surfactants may be mentioned. The surfactant that can be used in the present invention may be one type or two or more types. As the surfactant, silicone surfactants, nonionic surfactants, fluorine-containing surfactants, and acrylic surfactants are preferable, and silicone surfactants are particularly preferable.

  The addition amount of the surfactant that can be used in the present invention is preferably 0.01% by weight or more and 1% by weight or less, and preferably 0.1% by weight or more and 0.5% by weight or less with respect to the total amount of the film-forming coating solution. More preferably, it is not more than% by weight.

  In the present invention, the silicone-based surfactant is a surfactant containing at least one Si atom. The silicone surfactant used in the present invention may be any silicone surfactant and preferably has a structure containing alkylene oxide and dimethylsiloxane. A structure including the following chemical formula is more preferable.

  In said formula, R is a hydrogen atom or a C1-C5 alkyl group, x is an integer of 1-20, m and n are the integers of 2-100 each independently. Further, when there are a plurality of R, they may be the same or different.

  Examples of silicone surfactants that can be used in the present invention include BYK306, BYK307 (manufactured by BYK Chemie), SH7PA, SH21PA, SH28PA, SH30PA (manufactured by Toray Dow Corning Silicone), Troysol S366 (manufactured by Troy Chemical) Etc.

  The nonionic surfactant that can be used in the present invention may be any nonionic surfactant. For example, polyoxyethylene alkyl ethers, polyoxyethylene aryl ethers, polyoxyethylene dialkyl esters, sorbitan fatty acid esters, fatty acid-modified polyoxyethylenes, polyoxyethylene-polyoxypropylene block copolymers, etc. Can do.

  The fluorine-containing surfactant that can be used in the present invention may be any fluorine-containing surfactant. For example, perfluorooctyl polyethylene oxide, perfluorodecyl polyethylene oxide, perfluorodecyl polyethylene oxide and the like can be mentioned.

  The acrylic surfactant that can be used in the present invention may be any acrylic surfactant. For example, a (meth) acrylic acid type copolymer etc. are mentioned.

Any silane coupling agent may be used in the present invention.
Examples of the silane coupling agent include 3-glycidyloxypropyltrimethoxysilane, 3-aminoglycidyloxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 1 -Methacryloxypropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3 -Aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarboni -3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-triethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1, 4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N- Bis (oxyethylene) 3-aminopropyltrimethoxysilane, N- bis (oxyethylene) -3-aminopropyltriethoxysilane and the like. The silane coupling agent that can be used in the present invention may be used alone or in combination of two or more.

Any adhesion promoter may be used in the present invention.
Examples of the adhesion promoter include trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, and γ-glycidoxypropyltrimethoxysilane. , Β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, trimethoxyvinylsilane, γ-aminopropyltriethoxysilane, aluminum monoethylacetoacetate diisopropylate, vinyltris (2-methoxyethoxy) silane, N- (2 -Aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropylto Limethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, trimethylchlorosilane, dimethylvinylchlorosilane, methyldiphenylchlorosilane, chloromethyldimethylchlorosilane, trimethylmethoxysilane, dimethyldiethoxysilane, methyldimethoxysilane , Dimethylvinylethoxysilane, diphenyldimethoxysilane, phenyltriethoxysilane, hexamethyldisilazane, N, N′-bis (trimethylsilyl) urea, dimethyltrimethylsilylamine, trimethylsilylimidazole, vinyltrichlorosilane, benzotriazole, benzimidazole, Indazole, imidazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole 2-mercaptobenzoxazole, urazole, thiouracil, mercaptoimidazole, mercaptopyrimidine, 1,1-dimethylurea, 1,3-dimethylurea, thiourea compound and the like. Functional silane coupling agents are preferred as adhesion promoters.
The amount of adhesion promoter used is preferably 10 parts by weight or less, more preferably 0.05 to 5 parts by weight, based on 100 parts by weight of the total solid content.

In the film-forming composition of the present invention, a pore forming factor can be used within the range allowed by the mechanical strength of the film to make the film porous and to achieve a low dielectric constant.
The pore-forming factor as an additive that serves as a pore-forming agent is not particularly limited, but a nonmetallic compound is preferably used, solubility in a solvent used in a film-forming coating solution, and a polymer. It is necessary to satisfy the compatibility of
Further, the boiling point or decomposition temperature of the pore-forming agent is preferably 100 to 500 ° C, more preferably 200 to 450 ° C, and particularly preferably 250 to 400 ° C. The molecular weight is preferably 200 to 50,000, more preferably 300 to 10,000, and particularly preferably 400 to 5,000. The addition amount is preferably 0.5 to 75% by weight, more preferably 0.5 to 30% by weight, and particularly preferably 1 to 20% by weight with respect to the polymer forming the film.
The polymer may contain a decomposable group as a pore-forming factor, and the decomposition temperature is preferably 100 to 500 ° C, more preferably 200 to 450 ° C, and particularly preferably 250 to 400 ° C. It is. The content of the decomposable group is preferably 0.5 to 75 mol%, more preferably 0.5 to 30 mol%, and particularly preferably 1 to 20 mol% with respect to the polymer forming the film.

A film obtained using the film forming composition of the present invention is obtained by applying the film forming composition to a substrate by any method such as spin coating, roller coating, dip coating, or scanning, and then using a solvent. Can be formed by heat treatment. As a method of applying to the substrate, a spin coating method or a scanning method is preferable. Particularly preferred is the spin coating method. For spin coating, commercially available equipment can be used. For example, a clean truck series (manufactured by Tokyo Electron Co., Ltd.), D-spin series (manufactured by Dainippon Screen Mfg. Co., Ltd.), SS series or CS series (manufactured by Tokyo Ohka Kogyo Co., Ltd.) can be preferably used. The spin coating conditions may be any rotational speed, but from the viewpoint of in-plane uniformity of the film, a rotational speed of about 1,300 rpm is preferable for a 300 mm silicon substrate.
In addition, the composition solution discharge method may be either dynamic discharge in which the composition solution is discharged onto a rotating substrate or static discharge in which the composition solution is discharged onto a stationary substrate. From the viewpoint of uniformity, dynamic ejection is preferable. In addition, from the viewpoint of suppressing the consumption of the composition, it is also possible to use a method in which only the main solvent of the composition is preliminarily discharged onto the substrate to form a liquid film, and then the composition is discharged from there. it can. The spin coating time is not particularly limited, but is preferably within 180 seconds from the viewpoint of throughput. Further, from the viewpoint of transporting the substrate, it is also preferable to perform processing (edge rinse, back rinse) so as not to leave the film at the edge portion of the substrate.
The heat treatment method is not particularly limited, but generally used hot plate heating, heating method using a furnace, light irradiation heating using a xenon lamp by RTP (Rapid Thermal Processor), etc. are applied. Can do. A heating method using hot plate heating or furnace is preferable. Commercially available equipment can be preferably used as the hot plate, and the clean track series (manufactured by Tokyo Electron Ltd.), D-Spin series (manufactured by Dainippon Screen Mfg. Co., Ltd.), SS series or CS series (Tokyo Ohka Kogyo Co., Ltd.) )) And the like can be preferably used. As the furnace, α series (manufactured by Tokyo Electron Ltd.) and the like can be preferably used.

The film-forming composition of the present invention is particularly preferably cured by heat treatment after coating on a substrate. For example, the polymerization reaction at the time of post-heating of the carbon triple bond remaining in the film formed by the film-forming composition can be used. The conditions for this post-heat treatment are preferably 100 to 450 ° C., more preferably 200 to 420 ° C., particularly preferably 350 to 400 ° C., preferably 1 minute to 2 hours, more preferably 10 minutes to 1.5 ° C. Time, particularly preferably in the range of 30 minutes to 1 hour. The post-heating treatment may be performed in several times. Further, this post-heating is particularly preferably performed in a nitrogen atmosphere in order to prevent thermal oxidation by oxygen.
Moreover, in this invention, you may make it harden | cure by raise | generating the polymerization reaction of the carbon triple bond which remains in a polymer by irradiating a high energy ray instead of heat processing. Examples of high energy rays include electron beams, ultraviolet rays, and X-rays, but are not particularly limited to these methods.
The energy when an electron beam is used as the high energy beam is preferably 0 to 50 keV, more preferably 0 to 30 keV, and particularly preferably 0 to 20 keV. The total dose of the electron beam is preferably 0 to 5 μC / cm ² , more preferably 0 to ² μC / cm ² , and particularly preferably 0 to 1 μC / cm ² . 0-450 degreeC is preferable, as for the substrate temperature at the time of irradiating an electron beam, 0-400 degreeC is more preferable, and 0-350 degreeC is especially preferable. The pressure is preferably 0 to 133 kPa, more preferably 0 to 60 kPa, and particularly preferably 0 to 20 kPa. From the viewpoint of preventing oxidation of the polymer of the present invention, the atmosphere around the substrate is preferably an inert atmosphere such as Ar, He, or nitrogen. Further, a gas such as oxygen, hydrocarbon, or ammonia may be added for the purpose of reaction with plasma, electromagnetic waves, or chemical species generated by interaction with an electron beam. The electron beam irradiation in the present invention may be performed a plurality of times. In this case, the electron beam irradiation conditions need not be the same each time, and may be performed under different conditions each time.
Ultraviolet rays may be used as the high energy rays. The irradiation wavelength region when using ultraviolet rays is preferably 190 to 400 nm, and the output is preferably 0.1 to 2,000 mWcm ⁻² immediately above the substrate. The substrate temperature at the time of ultraviolet irradiation is preferably 250 to 450 ° C, more preferably 250 to 400 ° C, and particularly preferably 250 to 350 ° C. From the viewpoint of preventing oxidation of the polymer of the present invention, the atmosphere around the substrate is preferably an inert atmosphere such as Ar, He, or nitrogen. Further, the pressure at that time is preferably 0 to 133 kPa.

The film obtained by using the film forming composition of the present invention can be suitably used as an insulating film, and can be more suitably used as an interlayer insulating film for semiconductors. That is, the insulating film obtained using the film forming composition of the present invention can be suitably used for an electronic device.
For example, when used as an interlayer insulating film for a semiconductor, in the wiring structure, there may be a barrier layer on the side surface of the wiring to prevent metal migration, and CMP (chemical In addition to a cap layer and an interlayer adhesion layer that prevent peeling by mechanical mechanical polishing, there may be an etching stopper layer, etc. Furthermore, the interlayer insulating film layer may be divided into a plurality of layers with other materials as required. Also good.

  The film obtained using the film forming composition of the present invention can be etched for copper wiring or other purposes. Etching may be either wet etching or dry etching, but dry etching is preferred. For dry etching, either ammonia-based plasma or fluorocarbon-based plasma can be used as appropriate. These plasmas can use not only Ar but also oxygen, or gases such as nitrogen, hydrogen, and helium. In addition, after the etching process, ashing can be performed for the purpose of removing the photoresist or the like used for the processing, and further, cleaning can be performed to remove a residue at the time of ashing.

  The film obtained by using the film forming composition of the present invention can be subjected to CMP to planarize the copper plating portion after the copper wiring processing. As the CMP slurry (chemical solution), commercially available slurries (for example, manufactured by Fujimi Incorporated, manufactured by Rodel Nitta, manufactured by JSR, manufactured by Hitachi Chemical Co., Ltd., etc.) can be used as appropriate. Moreover, as a CMP apparatus, a commercially available apparatus (Applied Materials Co., Ltd., Ebara Manufacturing Co., Ltd. etc.) can be used suitably. Further, cleaning can be performed to remove slurry residues after CMP.

The film obtained using the film forming composition of the present invention can be used for various purposes. For example, it is suitable as an insulating film in electronic devices such as semiconductor devices such as LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM, and multi-chip module multilayer wiring boards. Interlayer insulating film for semiconductor, etching stopper film, surface protection In addition to films, buffer coat films, LSI passivation films, alpha ray blocking films, flexographic printing plate cover lay films, overcoat films, flexible copper clad cover coats, solder resist films, liquid crystal alignment films, etc. Can do.
Furthermore, as another application, the film obtained by using the film-forming composition of the present invention can be provided with conductivity by doping with an electron donor or acceptor, and used as a conductive film.

  The following examples illustrate the invention and are not intended to limit its scope.

<Synthesis Example 1: Synthesis of tris (4-ethynylphenyl) trimesoylamide (a)>

Under a nitrogen stream, 3 parts by weight of 4-ethynylaniline, 22 parts by weight of tetrahydrofuran (THF) and 3.1 parts of triethylamine were placed in a reaction vessel in a three-necked flask and stirred until uniform. While the container was cooled in an ice bath, 2.1 parts by weight of trimesoyl chloride was slowly added dropwise. After completion of dropping, the mixture was stirred at room temperature for 1 hour. After the reaction, ethyl acetate was added to the reaction solution and washed with 1N HNO ₃ aqueous solution and water. The extract was dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to obtain 3.6 parts by weight (yield: 91%) of compound (a).
¹ H-NMR (CDCl ₃ ) δ = 9.08 (br, 3H), 7.94 (br, 3H), 7.59 (d, 6H), 7.45 (d, 6H), 3.10 (s, 3H).

<Synthesis Example 2: Synthesis of tris (3-ethynylphenyl) trimesoylamide (b)>
The following compound (b) was synthesized in the same manner as in Synthesis Example 1 except that 4-ethynylaniline was replaced with 3-ethynylaniline.

<Synthesis Example 3: Synthesis of tris (3-ethynylphenyl) trimesoyl ester (c)>
Compound (c) was synthesized according to the synthesis method described in US Patent Application Publication No. 2006/0223898.

<Synthesis Example 4: Synthesis of 1,3-bis (3-ethynylphenyl) terephthalate (d)>
According to the following scheme, it synthesize | combined using the method similar to the synthesis example 1.

<Synthesis Example 5: Synthesis of Compound (e)>
According to the following scheme, it synthesize | combined using the method similar to the synthesis example 1.

<Synthesis Example 6: Synthesis of Compound (f)>
According to the following scheme, it synthesize | combined using the method similar to the synthesis example 1.

<Example 1>
1,3,5-triethynyladamantane was synthesized according to the synthesis method described in J. Polym. Sci. PART A Polym. Chem., Vol. 30, page 1747 (1992).
Next, 10 parts by weight of 1,3,5-triethynyladamantane and 56 parts by weight of t-butylbenzene are placed in a reaction vessel and heated to an internal temperature of 120 ° C. with stirring under a nitrogen stream. 5-Triethynyl adamantane was completely dissolved. Next, a solution obtained by dissolving 2.2 parts by weight of dicumyl peroxide (Park Mill D, manufactured by NOF Corporation) in 1.9 parts by weight of diphenyl ether was maintained for 1 hour while maintaining the internal temperature of the reaction liquid at 120 ° C. to 130 ° C. And added dropwise to the reaction solution.
After the reaction, the reaction solution was cooled to 50 ° C., added to 0.31 part by weight of 2-propanol, and the precipitated solid was filtered and washed with 2-propanol. The obtained polymer was dissolved in 36 parts by weight of THF, added to 0.32 parts by weight of methanol, and purified by reprecipitation. After vacuum drying, 4.2 parts by weight of polymer (1) having a weight average molecular weight of about 60,000 were obtained.
With the compounding amounts shown in Table 1, the polymer (1) and the compounds (a) to (f) obtained in Synthesis Examples 1 to 6 were added to prepare 1.0 parts by weight, respectively, which were cyclohexanone. A coating solution was prepared by completely dissolving in 9.0 parts by weight. This solution was filtered through a tetrafluoroethylene filter having a pore size of 0.1 μm, spin-coated on a silicon wafer, this coating film was heated on a hot plate at 250 ° C. for 60 seconds under a nitrogen stream, and further purged with nitrogen. As a result of baking in an oven at 400 ° C. for 60 minutes, a uniform film having a thickness of 0.5 μm and no defects was obtained.
The relative dielectric constant of the film (measurement temperature: 25 ° C., and so on) was calculated from the capacitance value at 1 MHz using a mercury probe manufactured by Four Dimensions and an HP4285ALCR meter manufactured by Yokogawa Hewlett-Packard Co., respectively. It was 2.67, 2.70, 2.80, 2.65, 2.82.
The appearance of the obtained insulating film was observed with a pocket micro loupe (50 times) manufactured by Peak Co., but no cracks were observed on the coating film surface.
The Young's modulus was measured using Nano Indenter SA2 manufactured by MTS.

<Example 2>
Next, 10 parts by weight of 1,3,5-trivinyladamantane and 56 parts by weight of t-butylbenzene were placed in a reaction vessel and heated to an internal temperature of 120 ° C. with stirring under a nitrogen stream. 5-Trivinyladamantane was completely dissolved. Next, a solution obtained by dissolving 2.2 parts by weight of dicumyl peroxide (Park Mill D, manufactured by NOF Corporation) in 1.9 parts by weight of diphenyl ether was maintained for 1 hour while maintaining the internal temperature of the reaction liquid at 120 ° C. to 130 ° C. And added dropwise to the reaction solution.
After the reaction, the reaction solution was cooled to 50 ° C., added to 0.31 part by weight of 2-propanol, and the precipitated solid was filtered and washed with 2-propanol. The obtained polymer was dissolved in 36 parts by weight of THF, added to 0.32 parts by weight of methanol, and purified by reprecipitation. After vacuum drying, 4.0 parts by weight of polymer (2) having a weight average molecular weight of about 60,000 was obtained.
With the compounding amounts shown in Table 1, the polymer (2) and the compounds (a) to (f) obtained in Synthesis Examples 1 to 6 were added to prepare 1.0 parts by weight, respectively, which were cyclohexanone. A coating solution was prepared by completely dissolving in 9.0 parts by weight. This solution was filtered through a tetrafluoroethylene filter having a pore size of 0.1 μm, spin-coated on a silicon wafer, this coating film was heated on a hot plate at 250 ° C. for 60 seconds under a nitrogen stream, and further purged with nitrogen. As a result of baking in an oven at 400 ° C. for 60 minutes, a uniform film having a thickness of 0.5 μm and no defects was obtained.
The relative dielectric constant of the film (measurement temperature: 25 ° C., the same applies hereinafter) was calculated from the capacitance value at 1 MHz using a mercury probe manufactured by Four Dimensions and a HP4285ALCR meter manufactured by Yokogawa Hewlett-Packard, respectively. It was 2.65, 2.66, 2.75, 2.63, 2.70.
The appearance of the obtained insulating film was observed with a pocket micro loupe (50 times) manufactured by Peak Co., but no cracks were observed on the coating film surface.
The Young's modulus was measured using Nano Indenter SA2 manufactured by MTS.

<Example 3>
A coating solution was prepared with 1.0 part by weight of the polymer (2) of Example 2 only. The obtained coating film was heated at 250 ° C. for 60 seconds on a hot plate under a nitrogen stream, and then baked in a 400 ° C. oven purged with nitrogen for 60 minutes. As a result, a uniform film having a thickness of 0.5 μm was obtained. was gotten.
The relative dielectric constant of the film (measurement temperature: 25 ° C., and so on) was calculated from the capacitance value at 1 MHz using a mercury probe manufactured by Four Dimensions and a HP4285ALCR meter manufactured by Yokogawa Hewlett-Packard Co., and found to be 2.63. there were.
The appearance of the obtained insulating film was observed with a pocket micro loupe (50 times) manufactured by Peak Co., but no cracks were observed on the coating film surface.
Moreover, when the Young's modulus was measured using Nano Indenter SA2 manufactured by MTS, it was 3.5 GPa.

<Comparative Example 1>
Only the polymer (1) of Example 1 was prepared at 1.0 part by weight. The obtained coating film was heated at 250 ° C. for 60 seconds on a hot plate under a nitrogen stream, and then baked in a 400 ° C. oven purged with nitrogen for 60 minutes. As a result, a uniform film having a thickness of 0.5 μm was obtained. was gotten.
The relative dielectric constant of the film (measurement temperature: 25 ° C., and so on) was calculated from the capacitance value at 1 MHz using a mercury probe manufactured by Four Dimensions and an HP4285ALCR meter manufactured by Yokogawa Hewlett-Packard, and found to be 2.65. there were.
The appearance of the obtained insulating film was observed with a pocket micro loupe (50 times) manufactured by Peak Co., but no cracks were observed on the coating film surface.
Moreover, it was 5.0 GPa when the Young's modulus was measured using Nano Indenter SA2 from MTS.

<Comparison of increase in dielectric constant with time, mechanical strength and heat resistance>
The heat resistance was evaluated by heating in air at 400 ° C. for 30 seconds and measuring the change in weight.

It can be seen that the insulating film formed using the film-forming composition of the present invention is excellent in heat resistance and mechanical strength, and exhibits a low dielectric constant and dielectric stability over time.
In addition, the addition amount of the compound (compound (A)) represented by the formula (1) in Table 1 and the addition amount of the compound (B) having a cage structure are the same as the compound represented by the formula (1) and the cage. It was expressed as the addition amount relative to the total amount with the compound having a mold structure.

Claims (10)

A compound represented by the following formula (1):
A film-forming composition comprising a compound having a cage structure.

(In Formula (1), A represents an ester bond or an amide bond, B represents an n ₁ -valent organic group, R ¹ represents a hydrogen atom or a monovalent substituent, and R ² represents a hydrogen atom or a monovalent group. N ₁ represents an integer from 1 to 6, n ₂ represents an integer from 0 to 4, n ₃ represents an integer from 1 to 5, and satisfies n ₂ + n ₃ = 5 .)   The film-forming composition according to claim 1, wherein the compound having a cage structure is a polymer having a cage structure.   The film-forming composition according to claim 2, wherein the polymer having a cage structure is a polymer of a monomer having a cage structure.   The film-forming composition according to claim 3, wherein the polymer having a cage structure is obtained by polymerizing a monomer having a cage structure in the presence of a radical initiator or a transition metal catalyst.   The film-forming composition according to claim 3, wherein the monomer having a cage structure has at least one of a polymerizable carbon-carbon double bond and carbon-carbon triple bond.   The film-forming composition according to any one of claims 1 to 4, wherein the cage structure is a structure selected from the group consisting of adamantane, biadamantane, diamantane, triamantane, and tetramantane. The film-forming composition according to claim 3, wherein the monomer having a cage structure is a monomer selected from the group consisting of monomers represented by the following formulas (2) to (7).

(In formulas (2) to (7), X _{1 to} X ₈ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a silyl group, an acyl group, an alkoxycarbonyl group or a carbamoyl group. Y _{1 to} Y ₈ each independently represents a halogen atom, an alkyl group, an aryl group or a silyl group, m ₁ and m ₅ represent an integer of ₁ to 16, and n ₁ and n ₅ represent 0 to 15 It represents an _{integer, m 2, m 3, m} 6, m 7 each independently represents an integer of _{1~15, n 2, n 3,} n 6, n 7 is an integer of 0 to 14, m _4, m ₈ represents an integer of 1 to 20, and n ₄ and n ₈ represent an integer of 0 to 19.)   The composition for insulating-film formation as described in any one of Claims 1-7.   The insulating film obtained using the composition for insulating film formation of Claim 8.   An electronic device having the insulating film according to claim 9.