JP6366136B2 - Epoxy resin composition, resin sheet, prepreg, metal-clad laminate, printed wiring board - Google Patents

Description

  The present invention relates to an epoxy resin composition, a resin sheet obtained by coating it on a surface support, a prepreg impregnated in a fiber base, a metal-clad laminate, a printed wiring board, and a semiconductor device.

In recent years, with the demand for higher functionality and lighter, thinner and smaller electronic devices, high-density integration and further high-density mounting of electronic components have been promoted. The miniaturization of semiconductor devices used in these electronic devices The process is progressing rapidly.
For this reason, printed wiring boards on which electronic components including semiconductor elements are mounted tend to be thinned, and a resin board used for the printed wiring board has a thickness of about 0.8 mm.
More recently, a package-on-package (hereinafter referred to as POP) in which semiconductor packages using a resin substrate of 0.4 mm or less are stacked is mounted on a mobile device (for example, a mobile phone, a smartphone, a tablet PC, etc.). Has been. This trend is further accelerated, and it is certain that the thickness will be reduced year by year (Non-Patent Document 1).

JP 2013-43958 A

Semiconductor Technology Roadmap Technical Committee 2009 Report Chapter 8 WG7 Implementation Hitachi Chemical Technical Report No.56 (December 2013) [Searched on July 29, 2014], Internet <URL: http://www.hitachi-chem.co.jp/english/report/056/56_tr02. pdf> Risho Kogyo RISHO NEWS Technical Report No91 [searched July 29, 2014], Internet <URL: http://wwww.risho.co.jp/rishonews/technical_report/tr91/r180_tr91.pdf>

As semiconductor devices become smaller in this way, they often go through a process at a high temperature exceeding 200 ° C. when creating a substrate, and if the thickness of the substrate is thin, the rigidity becomes insufficient and distortion occurs during the process. Or productivity deteriorates when the subject of deforming comes out.
Furthermore, the thickness of the semiconductor element and the sealing material, which conventionally has been responsible for most of the rigidity of the semiconductor device, becomes extremely thin, and the semiconductor device is likely to warp in the mounting process. In addition, since the proportion of the resin substrate as a constituent member increases, the physical properties and behavior of the resin substrate have a great influence on the warpage of the semiconductor device.
On the other hand, as lead-free solder progresses from the viewpoint of protecting the global environment, the maximum temperature in the reflow process that occurs when mounting semiconductor elements on printed circuit boards or mounting semiconductor packages on motherboards becomes very high. It is coming. Since the melting point of commonly used lead-free solder is about 210 degrees, the maximum temperature during the reflow process is a level exceeding 260 degrees.
In general, the difference in thermal expansion between a semiconductor element and a printed wiring board on which the semiconductor element is mounted is very large. For this reason, the resin substrate may be greatly warped in the reflow process performed when the semiconductor element is mounted on the printed wiring board. Similarly, in the reflow process that is performed when the semiconductor package is mounted on the mother board, the resin substrate may be greatly warped.

On the other hand, Patent Document 1 discloses a phenol novolac resin having a biphenyl skeleton and a phenol novolac type epoxy resin obtained by epoxidizing the phenol novolak resin, and describes its usefulness for use as a semiconductor encapsulant. However, there is no description about the characteristics of the composition containing these epoxy resins and cyanate ester compounds, and there is no description about the usefulness of the printed wiring board.

Therefore, an object of the present invention is to provide a resin substrate in which warpage occurring in the heating step in the substrate creation step and / or the mounting step is suppressed.

（式中、（ａ）（ｂ）の比率は（ａ）／（ｂ）=１〜３である。Ｇはグリシジル基を表す。ｎは繰り返し数であり、０〜５である。）
（２）
前項（１）に記載のエポキシ樹脂組成物を繊維基材に含浸してなるプリプレグ、
（３）
前記繊維素材がガラス繊維基材である前項（２）に記載のプリプレグ、
（４）
前記ガラス繊維基材がＴガラス、Ｓガラス、Ｅガラス、ＮＥガラス、および石英ガラスからなる群から選ばれる少なくとも一種を含む、前項（２）又は（３）のいずれか一項に記載のプリプレグ、
（５）
前項（２）及至（４）に記載のプリプレグの少なくとも一方の面に金属箔が積層された、金属張積層板、
（６）
前項（１）に記載のエポキシ樹脂組成物からなる絶縁層をフィルム上に、又は金属箔上に形成してなる樹脂シート、
（７）
前項（５）に記載の金属張積層板を回路基板に用いてなるプリント配線基板、
（８）
前項（２）及至（４）のいずれか一項に記載のプリプレグ、及び／又は前項（６）に記載の樹脂シートを硬化してなるプリント配線基板、
（９）
前項（７）又は（８）のいずれか一項に記載のプリント配線基板に半導体素子を搭載してなる半導体装置、
を提供するものである。 As a result of intensive studies to solve the above problems, the present inventors have completed the present invention.
That is, the present invention provides (1)
An epoxy resin composition comprising, as an essential component, an epoxy resin represented by the following general formula (1) and a cyanate ester compound having two or more cyanate groups in the molecule;

(In the formula, the ratio of (a) and (b) is (a) / (b) = 1 to 3. G represents a glycidyl group. N is the number of repetitions and is 0 to 5.)
(2)
A prepreg obtained by impregnating a fiber base material with the epoxy resin composition according to item (1),
(3)
The prepreg according to (2) above, wherein the fiber material is a glass fiber substrate,
(4)
The prepreg according to any one of (2) and (3) above, wherein the glass fiber substrate contains at least one selected from the group consisting of T glass, S glass, E glass, NE glass, and quartz glass,
(5)
A metal-clad laminate in which a metal foil is laminated on at least one surface of the prepreg described in the preceding paragraphs (2) to (4),
(6)
A resin sheet formed by forming an insulating layer made of the epoxy resin composition according to item (1) on a film or a metal foil;
(7)
A printed wiring board using the metal-clad laminate as described in (5) above for a circuit board;
(8)
A printed wiring board obtained by curing the prepreg according to any one of (2) and (4) above and / or the resin sheet according to (6) above;
(9)
A semiconductor device in which a semiconductor element is mounted on the printed wiring board according to any one of (7) and (8);
Is to provide.

  Since the epoxy resin composition of the present invention has both excellent heat resistance and high flexural modulus in a high temperature region in the cured product, it is extremely useful for producing laminated boards such as printed wiring boards and build-up boards. Material.

（式中、（ａ）（ｂ）の比率は（ａ）／（ｂ）=１〜３である。Gはグリシジル基を表す。ｎは繰り返し数であり、０〜５である。） The epoxy resin composition of the present invention will be described.
The epoxy resin composition of the present invention contains an epoxy resin represented by the following general formula (1) as an essential component.

(In the formula, the ratio of (a) and (b) is (a) / (b) = 1 to 3. G represents a glycidyl group. N is the number of repetitions and is 0 to 5.)

The epoxy resin of the present invention can be synthesized by the methods described in JP2011-252037, JP2008-156553, JP2013-043958, International Publication WO2012 / 053522, WO2007 / 007827, Any method may be used as long as it has the structure of the formula (1).
However, in the present invention, it is particularly preferable to use a product in which the ratio (polyfunctionalization ratio) of the formula (a) to the formula (b) is (a) / (b) = 1-3. When the structure (a) is large, the heat resistance is improved, but the water absorption characteristics are deteriorated, and the structure becomes brittle and hard. Therefore, a polyfunctionalization rate within the above range is preferable.

The softening point (ring and ball method) of the epoxy resin to be used is preferably 50 to 150 ° C, more preferably 52 to 100 ° C, and particularly preferably 52 to 95 ° C. Below 50 ° C., stickiness is severe, handling is difficult, and productivity is problematic. Moreover, when it is 150 degreeC or more, it is a temperature close | similar to molding temperature, and since the fluidity | liquidity at the time of shaping | molding cannot be ensured, it is not preferable.

  The epoxy equivalent of the epoxy resin used is 180 to 350 g / eq. It is preferable that Especially 190-300 g / eq. It is. Epoxy equivalent is 180 g / eq. In the case of cutting, since there are too many functional groups, the cured product after curing tends to have a high water absorption rate and become brittle. Epoxy equivalent is 350 g / eq. If it exceeds 1, the softening point becomes very large or the epoxidation has not progressed neatly, which is not preferable because the amount of chlorine resulting from epichlorohydrin used as a raw material becomes very large.

  In addition, the chlorine content of the epoxy resin used in the present invention is 200 to 1500 ppm, particularly preferably 200 to 900 ppm in terms of total chlorine (hydrolysis method). From the JPCA standard, it is desired that epoxy alone does not exceed 900 ppm. Furthermore, a large amount of chlorine is undesirable because it affects the electrical reliability. When it is less than 200 ppm, an excessive purification step is required, which causes a problem in productivity, which is not preferable.

  In addition, the melt viscosity in 150 degreeC of the epoxy resin used in this invention is 0.05-5 Pa.s. In particular, it is 0.05 to 2.0 Pa · s. If the viscosity is high, there will be a problem with fluidity, and there will be a problem with flowability and embedding during pressing. When the pressure is less than 0.05 Pa · s, the molecular weight is too small and the heat resistance is insufficient.

In the above formula, the ratio of (a) to (b) is (a) / (b) = 1-3. That is, more than half are glycidyl ethers having a resorcin structure. This ratio is important for the precipitation of crystals and the improvement of heat resistance, and (a) / (b) preferably exceeds 1. Moreover, water absorption and toughness can be improved by restrict | limiting the quantity of the glycidyl ether body of a resorcinol structure because (a) / (b) is 3 or less.
In said formula, n is a repeating unit and is 0-5. When n does not exceed 5, the flowability and fluidity of the prepreg or resin sheet are controlled. When this exceeds 5, it is not preferable because not only the fluidity but also the solubility in a solvent arises.
In the epoxy resin used in the present invention, solubility in a solvent is important. In the case of a biphenyl aralkyl type epoxy resin having a similar skeleton, solubility is required in solvents such as methyl ethyl ketone, toluene, propylene glycol monomethyl ether and the like.
In particular, solubility in methyl ethyl ketone is important, and crystals are not precipitated for 2 months or more at 5 ° C., room temperature or the like. Although it is also related to the ratio of (a) / (b) described above, it is important that (a) / (b) exceeds 1 because a crystal is likely to appear when the value of (a) is large. .

The epoxy resin composition of the present invention contains a cyanate ester compound having two or more cyanato groups in the molecule as an essential component.
As the cyanate ester compound, conventionally known cyanate ester compounds can be used. Specific examples of cyanate ester compounds include polycondensates of phenols and various aldehydes, polymers of phenols and various diene compounds, polycondensates of phenols and ketones, and polycondensations of bisphenols and various aldehydes. And cyanate ester compounds obtained by reacting phenols and aromatic dimethanols, phenols and aromatic dichloromethyls, phenols and aromatic bisalkoxymethyls with cyanogen halides, etc. It is not limited. These may be used alone or in combination of two or more.

Examples of the phenols include phenol, alkyl-substituted phenol, aromatic-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene, and dihydroxynaphthalene.

Examples of the various aldehydes include formaldehyde, acetaldehyde, alkyl aldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, crotonaldehyde, and cinnamaldehyde.

Examples of the various diene compounds include dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, and isoprene.

Examples of the ketones include acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, and benzophenone.

As mentioned above, aromatic dimethanols such as benzenedimethanol and biphenyldimethanol, aromatic dichloromethyls as α, α'-dichloroxylene, bischloromethylbiphenyl and the like, and aromatic bisalkoxymethyls as bismethoxymethyl Examples include benzene, bismethoxymethylbiphenyl, bisphenoxymethylbiphenyl, and the like.

（式中、Ｒ１は下記式（２‘）構造を示し、Ｒ２及びＲ３は、水素原子又は炭素数１〜４のアルキル基を示し、それぞれ同じであっても、異なっても良い。）

Specific examples of the cyanate ester compound used in the epoxy resin composition of the present invention include, but are not limited to, compounds represented by the following general formulas (2) to (4).

(Wherein R1 represents the structure of the following formula (2 ′), R2 and R3 represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and may be the same or different.)

（式中、複数存在するＲはそれぞれ独立して存在し、水素原子、炭素数１〜５のアルキル基もしくはフェニル基を表す。ｎは平均値であり１＜ｎ≦２０を表す。）

(In the formula, a plurality of R's are present independently and each represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a phenyl group. N is an average value and 1 <n ≦ 20.)

In the present invention, particularly preferably, in the formula (2), R1 is a methylene group, isopropylidene group or tricyclodecane structure, or a resin having the structure of the formula (4).
As a specific method for synthesizing these cyanate compounds, for example, JP-A-2005-264154 (Cited document 5) describes a synthesis method.

The compounding amount of the cyanate ester compound is not particularly limited. However, in the case of a compound mainly composed of a cyanate ester and an epoxy, 0.1 to 1.4 equivalents with respect to the functional group equivalent (cyanate ester equivalent) of the cyanate ester compound, preferably It is preferable to add 0.2 to 1.4, more preferably 0.5 to 1.4 equivalents of epoxy resin.
This blending amount is also influenced by the catalyst used and the material to be blended. For example, specifically, in the case of a nitrogen-containing catalyst such as imidazole, anionic polymerization of epoxies occurs simultaneously, so 0.8 to 1.4 Equivalent weight is particularly preferred.
Moreover, when mix | blending an epoxy resin hardening | curing agent, it is preferable to mix | blend an epoxy resin of 0.5-1.4 equivalent with respect to the total functional group equivalent of a hardening | curing agent and cyanate ester. Furthermore, when blending resins such as maleimide resins that can be cured simultaneously and crosslinked with epoxy resins or cyanate esters, it is necessary to subtract the amount corresponding to their functional group equivalents, but react with epoxy. It is particularly preferable that the functional group having a functional group is 0.5 to 1.4 equivalents.

  In the epoxy resin composition of the present invention, other epoxy resins can be used in combination. Specific examples of other epoxy resins that can be used in combination with the epoxy resin used in the present invention include bisphenols (bisphenol A, bisphenol F, bisphenol S, biphenol, bisphenol AD, etc.) or phenols (phenol, alkyl-substituted phenol, aromatic Group-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene, dihydroxynaphthalene, etc.) and various aldehydes (formaldehyde, acetaldehyde, alkylaldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde) , Crotonaldehyde, cinnamaldehyde, etc.); said phenols Polymers with various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, isoprene, etc.); the phenols and ketones ( Polycondensates of acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.); polycondensates of the above phenols with aromatic dimethanols (benzene dimethanol, biphenyl dimethanol, etc.); the above phenols and aromatic Polycondensates with dichloromethyls (α, α'-dichloroxylene, bischloromethylbiphenyl, etc.); the phenols and aromatic bisalkoxymethyls (bismethoxymethylbenzene, bismeth Polycondensates with xymethylbiphenyl, bisphenoxymethylbiphenyl, etc .; glycidyl ether epoxy resins, alicyclic epoxy resins, glycidylamine epoxies obtained by glycidylation of polycondensates of the above bisphenols and various aldehydes or alcohols, etc. Resins, glycidyl ester epoxy resins and the like can be mentioned, but not limited to these as long as they are usually used epoxy resins. These may be used alone or in combination of two or more.

When mix | blending the epoxy resin composition of this invention, a conventionally well-known epoxy resin hardening | curing agent can be used together. Specific examples of epoxy resin curing agents that can be used in combination include amine compounds, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methyl nadic anhydride Acid anhydride compounds such as hexahydrophthalic anhydride and methylhexahydrophthalic anhydride, bisphenols, phenols (phenol, alkyl-substituted phenol, aromatic-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene , Dihydroxynaphthalene, etc.) and various aldehydes (formaldehyde, acetaldehyde, alkyl aldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde) Polycondensates with glutaraldehyde, phthalaldehyde, crotonaldehyde, cinnamaldehyde, etc., phenols and various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, Polymers with diisopropenylbiphenyl, butadiene, isoprene, etc.), polycondensates with phenols and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.), etc. It is not a thing. These may be used alone or in combination of two or more. These blending amounts are in the range of 2 times or less, preferably 1 time or less of the epoxy resin in weight ratio.

  The amount of the curing agent used in the epoxy resin composition of the present invention is preferably 1 equivalent or less with respect to 1 equivalent of the epoxy group of the epoxy resin. When the epoxy group exceeds 1 equivalent, when the reaction between epoxy and cyanate proceeds, the curing agent is left behind, and curing may be incomplete, and good cured properties may not be obtained. Most preferably, it is 0.1-0.98. In the present invention, a preferable combination of an epoxy resin and a curing agent is an epoxy resin having a softening point of 45 to 140 degrees (more preferably 50 to 100 ° C.) and a curing agent having a softening point of 50 to 140 ° C. (preferably 55 to 120 ° C.). It is. A resin composition having balanced properties in terms of fluidity, flame retardancy, and heat resistance is obtained.

In the epoxy resin composition of the present invention, a maleimide resin may be added. Although it will not specifically limit if it is a commercially available maleimide resin, the hydrogen on an aromatic ring is substituted by 1 to 4 carbon atoms with an alkyl group having 1 to 3 carbon atoms, or an unsubstituted bismaleimide phenylmethane or a phenol novolac type maleimide resin. Can be mentioned.
The maleimide resin is not a reaction in an equivalent amount with the cyanate resin, but is polymerized in a form incorporated individually or randomly, so the mixing ratio is not particularly limited, but in order to bring out the characteristics of the epoxy resin composition of the present invention The total amount of epoxy resin, cyanate ester and maleimide resin is preferably 10 to 45% by weight, particularly preferably 10 to 40% by weight.

  The epoxy resin composition of the present invention may contain a curing accelerator. Specific examples of curing accelerators that can be used include imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2- (dimethylaminomethyl) phenol, 1,8-diaza- And tertiary amines such as bicyclo (5,4,0) undecene-7, phosphines such as triphenylphosphine, and metal compounds such as tin octylate. The curing accelerator is used as necessary in an amount of 0.1 to 5.0 parts by weight based on 100 parts by weight of the epoxy resin.

  In the epoxy resin composition of the present invention, additives such as flame retardants and fillers can be blended as necessary within a range that does not deteriorate the attractive properties and heat resistance of the cured product.

  The flame retardant blended as necessary is not particularly limited, but a flame retardant having no reactivity with a cyanate group is preferable. Here, when the flame retardant is added to the printed wiring board resin composition, the flame retardant is a cyanate group of the cyanate ester compound even when mixed within a range of 300 ° C. or lower. It is included in the printed wiring board resin composition as it is in the form of dispersion or dissolution without reacting with the resin. This reaction does not include the reaction of the flame retardant when the resin composition is heated and burned. In general, the production and use of a resin composition for a printed wiring board and varnishes, prepregs, metal-clad laminates, printed wiring boards, and the like using the resin composition are performed within a range of 300 ° C. or lower.

  The filler to be blended as necessary is not particularly limited, but as inorganic filler, fused silica, crystalline silica, alumina, calcium carbonate, calcium silicate, barium sulfate, talc, clay, magnesium oxide, aluminum oxide, Examples include beryllium oxide, iron oxide, titanium oxide, aluminum nitride, silicon nitride, boron nitride, mica, glass, quartz, and mica. Further, it is also preferable to use a metal hydroxide such as magnesium hydroxide or aluminum hydroxide in order to impart a flame retardant effect. However, it is not limited to these. Two or more kinds may be mixed and used. Of these inorganic fillers, silicas such as fused silica and crystalline silica are preferred because of low cost and good electrical reliability. In the epoxy resin composition of the present invention, the amount of the inorganic filler used is usually 5% to 70% by weight, preferably 10% to 60% by weight, more preferably 15% to 60% by weight. It is. If the amount is too small, the effect of flame retardancy cannot be obtained, and the elastic modulus decreases.If the amount is too large, the filler settles out when the varnish is dissolved in the sealing solution, and a homogeneous molded body is formed. It may not be obtained.

In addition, although the shape of a inorganic filler, a particle size, etc. are not specifically limited, Usually, a particle size is 0.01-50 micrometers, Preferably it is a thing of 0.1-15 micrometers.

  A coupling agent can be blended in the epoxy resin composition of the present invention in order to enhance the adhesion between the glass cloth or the inorganic filler and the resin component. Any conventionally known coupling agent can be used. For example, vinyl alkoxy silane, epoxy alkoxy silane, styryl alkoxy silane, methacryloxy alkoxy silane, acryloxy alkoxy silane, amino alkoxy silane, mercapto alkoxy silane, isocyanate alkoxy Examples include various alkoxysilane compounds such as silane, alkoxytitanium compounds, and aluminum chelates. These may be used alone or in combination of two or more. The coupling agent may be added by treating the surface of the inorganic filler with the coupling agent in advance and then kneading with the resin, or mixing the coupling agent with the resin and then kneading the inorganic filler. .

An organic solvent can be added to the epoxy resin composition of the present invention to obtain a varnish-like composition (hereinafter simply referred to as varnish). Examples of the solvent used include amide solvents such as γ-butyrolactone, N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylimidazolidinone, and tetramethylene sulfone. Sulfones, ether solvents such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether monoacetate, propylene glycol monobutyl ether, ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone Aromatic solvents such as solvent, toluene, xylene and the like can be mentioned. The solvent is used in such a range that the solid content concentration excluding the solvent in the obtained varnish is usually 10 to 80% by weight, preferably 20 to 70% by weight.

  Furthermore, a known additive can be blended in the epoxy resin composition of the present invention as necessary. Specific examples of additives that can be used include polybutadiene and modified products thereof, modified products of acrylonitrile copolymer, polyphenylene ether, polystyrene, polyethylene, polyimide, fluororesin, maleimide compounds, cyanate ester compounds, silicone gel, and silicone oil. And colorants such as carbon black, phthalocyanine blue, and phthalocyanine green.

The resin sheet of the present invention will be described.
The sheet using the epoxy resin composition of the present invention has a thickness after drying the varnish on a planar support by various coating methods such as gravure coating, screen printing, metal masking, and spin coating methods known per se. Can be obtained by drying after coating so as to have a predetermined thickness, for example, 5 to 100 μm, but which coating method is used depends on the type, shape, size, thickness of coating, and support It is appropriately selected depending on the heat resistance and the like. Examples of the planar support include various types such as polyamide, polyamideimide, polyarylate, polyethylene terephthalate, polybutylene terephthalate, polyetherketone, polyetherimide, polyetheretherketone, polyketone, polyethylene, polypropylene, and Teflon (registered trademark). Examples thereof include films made from molecules and / or copolymers thereof, and metal foils such as copper foils.
After application, the composition can be dried to obtain a sheet-like composition (sheet of the present invention), but the sheet can be further heated to obtain a sheet-like cured product. Moreover, you may serve as a solvent drying and hardening process by one heating.
The epoxy resin composition of the present invention can be coated and heated on both sides or one side of the support by the above method to form the cured product layer of the present invention on both sides or one side of the support. Moreover, it is also possible to create a laminate by bonding and adhering the adherend before curing.
Further, the sheet of the present invention can be used as an adhesive sheet by peeling it from the support, and can be brought into contact with the adherend, applied with pressure and heat as necessary, and bonded together with curing.

The prepreg of the present invention will be described.
The prepreg of the present invention is obtained by impregnating a fiber base material with the above resin composition. Thereby, the prepreg excellent in heat resistance, low expansibility, and a flame retardance can be obtained. Examples of the fiber base material include glass fiber base materials such as glass woven fabric, glass non-woven fabric, and glass paper, paper, aramid, polyester, aromatic polyester, and synthetic fibers such as fluororesin, etc. Examples thereof include woven fabrics, nonwoven fabrics, mats and the like made of fibers, carbon fibers, mineral fibers and the like. These substrates may be used alone or in combination. Among these, a glass fiber base material is preferable. Thereby, the rigidity and dimensional stability of a prepreg can be improved.
As a glass fiber base material, what contains at least 1 type chosen from the group which consists of T glass, S glass, E glass, NE glass, and quartz glass is preferable.

Examples of the method of impregnating the fiber base material with the resin composition include a method of immersing the base material in a resin varnish, a method of applying with various coaters, and a method of spraying with a spray. Among these, the method of immersing the base material in the resin varnish is preferable. Thereby, the impregnation property of the resin composition with respect to a base material can be improved. In addition, when a base material is immersed in a resin varnish, a normal impregnation coating equipment can be used.
For example, after impregnating a base material such as a glass cloth as it is or in the form of a varnish dissolved or dispersed in a solvent, the epoxy resin composition of the present invention is usually 80 to 200 ° C. (however, When the solvent is used, the prepreg is obtained by drying for 2 to 30 minutes, preferably 2 to 15 minutes, at a temperature equal to or higher than the temperature at which the solvent can be volatilized.

The metal-clad laminate of the present invention will be described.
The laminate used in the present invention is formed by heating and pressing the above prepreg. Thereby, the printed wiring board excellent in heat resistance, low expansibility, and a flame retardance can be obtained. When one prepreg is used, the metal foil is overlapped on both the upper and lower surfaces or one surface. Two or more prepregs can be laminated. When two or more prepregs are laminated, a metal foil or film is laminated on the outermost upper and lower surfaces or one surface of the laminated prepreg. Next, a printed wiring board can be obtained by heat-pressing a laminate of a prepreg and a metal foil. Although the temperature to heat is not specifically limited, 120-220 degreeC is preferable and especially 150-200 degreeC is preferable. Although the pressure to pressurize is not particularly limited, it is preferably 1.5 to 5 MPa, and particularly preferably 2 to 4 MPa. Moreover, you may perform post-curing at the temperature of 150-300 degreeC with a high-temperature soot as needed.

The printed wiring board of the present invention will be described.
The printed wiring board uses the laminated board as an inner layer circuit board. Circuits are formed on one or both sides of the laminate. In some cases, through holes can be formed by drilling or laser processing, and electrical connection on both sides can be achieved by plating or the like.

A commercially available or resin sheet of the present invention or the prepreg of the present invention is superimposed on the internal circuit board and subjected to heat and pressure molding to obtain a multilayer printed wiring board.
Specifically, the insulating layer side of the resin sheet and the inner layer circuit board are combined, vacuum-pressed using a pressure-pressing laminator, etc., and then the insulating layer is heat-cured with a hot-air dryer or the like. Can be obtained.
Although it does not specifically limit as conditions to heat-press form here, if an example is given, it can implement at the temperature of 60-160 degreeC, and the pressure of 0.2-3 MPa. Moreover, it is although it does not specifically limit as conditions to heat-harden, If an example is given, it can implement in temperature 140-240 degreeC and time 30-120 minutes.
Alternatively, the prepreg of the present invention can be obtained by superimposing the prepreg on an inner circuit board and subjecting it to hot pressing using a flat plate press or the like. Although it does not specifically limit as conditions to heat-press form here, For example, it can implement at the temperature of 140-240 degreeC, and the pressure of 1-4 MPa. In the heat and pressure forming by such a flat plate press apparatus or the like, the insulating layer is heat-cured simultaneously with the heat and pressure forming.

Further, the method for producing a multilayer printed wiring board according to the present invention includes a step of continuously laminating the resin sheet or the prepreg of the present invention on a surface on which an inner layer circuit pattern of the inner layer circuit board is formed, and a conductor circuit Forming a layer by a semi-additive process.

Curing of the resin sheet or the insulating layer formed from the prepreg of the present invention may be left in a semi-cured state in order to facilitate the subsequent laser irradiation and removal of the resin residue and improve desmearability. In addition, the first insulating layer is partially cured (semi-cured) by heating at a temperature lower than the normal heating temperature, and one or more insulating layers are further formed on the insulating layer to form a semi-cured insulating layer. By heat-curing again to such an extent that there is no practical problem, the adhesion between the insulating layer and between the insulating layer and the circuit can be improved. The semi-curing temperature in this case is preferably 80 ° C to 200 ° C, more preferably 100 ° C to 180 ° C. In the next step, laser is irradiated to form an opening in the insulating layer, but it is necessary to peel off the substrate before that. There is no particular problem with the peeling of the base material either after the insulating layer is formed, before heat curing, or after heat curing.
The inner layer circuit board used when obtaining the multilayer printed wiring board is preferably, for example, one in which a predetermined conductor circuit is formed by etching or the like on both surfaces of a copper clad laminate and the conductor circuit portion is blackened. Can be used.

Resin residues after laser irradiation are preferably removed with an oxidizing agent such as permanganate or dichromate. Further, the surface of the smooth insulating layer can be simultaneously roughened, and the adhesion of the conductive wiring circuit formed by subsequent metal plating can be improved.

Next, an outer layer circuit is formed. The outer layer circuit is formed by connecting the insulating resin layers by metal plating and forming an outer layer circuit pattern by etching. A multilayer printed wiring board can be obtained in the same manner as when a resin sheet or prepreg is used.
When a resin sheet having a metal foil or a prepreg is used, a circuit may be formed by etching for use as a conductor circuit without peeling off the metal foil. In that case, if an insulating resin sheet with a base material using a thick copper foil is used, it becomes difficult to make a fine pitch in subsequent circuit pattern formation, so use an ultrathin copper foil of 1 to 5 μm, or 12 to 18 μm. In some cases, the copper foil is half-etched to a thickness of 1 to 5 μm by etching.

Further, an insulating layer may be stacked and a circuit may be formed in the same manner as described above. However, in the design of the multilayer printed wiring board, a solder resist is formed on the outermost layer after the circuit is formed. The method for forming the solder resist is not particularly limited. For example, a method of laminating (laminating) a dry film type solder resist, forming by exposure and development, or forming a printed liquid resist by exposure and development It is done by the method to do. In addition, when using the obtained multilayer printed wiring board for a semiconductor device, the electrode part for a connection is provided in order to mount a semiconductor element. The connecting electrode portion can be appropriately coated with a metal film such as gold plating, nickel plating, or solder plating. A multilayer printed wiring board can be manufactured by such a method.

Next, the semiconductor device of the present invention will be described.
A semiconductor element having solder bumps is mounted on the multilayer printed wiring board obtained as described above, and connection with the multilayer printed wiring board is attempted through the solder bumps. A liquid sealing resin is filled between the multilayer printed wiring board and the semiconductor element to form a semiconductor device. The solder bump is preferably made of an alloy made of tin, lead, silver, copper, bismuth or the like.
The connection method between the semiconductor element and the multilayer printed wiring board is to align the connection electrode part on the substrate with the solder bump of the semiconductor element using a flip chip bonder, etc. The solder bumps are heated to the melting point or higher by using a heating device, and the multilayer printed wiring board and the solder bumps are connected by fusion bonding. In order to improve connection reliability, a metal layer having a relatively low melting point, such as solder paste, may be formed in advance on the connection electrode portion on the multilayer printed wiring board. Prior to this joining step, the connection reliability can be improved by applying a flux to the solder bumps and / or the surface layer of the connection electrode portion on the multilayer printed wiring board.

As a substrate, it is used as a motherboard, a network substrate, a package substrate, etc., and used as a substrate. Especially as a package substrate, it is useful as a thin layer substrate for a single-sided sealing material. In addition, when used as a semiconductor encapsulant, examples of semiconductor devices obtained from the blending include DIP (Dual Inline Package), QFP (Quad Flat Package), BGA (Ball Grid Array), CSP (Chip Size Package). SOP (Small Outline Package), TSOP (Thin Small Outline Package), TQFP (Sink Quad Flat Package), and the like.

The features of the present invention will be described more specifically with reference to synthesis examples and examples. The following materials, processing details, processing procedures, and the like can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.
Here, the measurement conditions of each physical property value are as follows.
-Epoxy equivalent Measured by the method described in JIS K-7236, the unit is g / eq. It is.
-Softening point It measures by the method based on JISK-7234, and a unit is (degreeC).
-Elastic modulus (DMA)
Dynamic viscoelasticity measuring instrument: TA-insRents, DMA-2980
Measurement temperature range: -30 to 280 ° C
Temperature rate: 2 ° C./min Sample size: 5 mm × 50 mm cut out was used Tg: Tan-δ peak point in DMA measurement was defined as Tg

Synthesis example 1
A phenol resin represented by the following formula ((a) / (b) = 1.3 n = 0.5) produced according to WO2007 / 007827 while performing a nitrogen purge on a flask equipped with a stirrer, a reflux condenser, and a stirrer. (Calculated from molecular weight distribution and hydroxyl equivalent in GPC) Hydroxyl equivalent 134g / eq. Softening point 93 ° C) 134 parts, 450 parts of epichlorohydrin, 54 parts of methanol were added, dissolved under stirring, and heated to 70 ° C. did. Next, 42.5 parts of flaky sodium hydroxide was added in portions over 90 minutes, and the reaction was further carried out at 70 ° C. for 1 hour. After completion of the reaction, the mixture was washed with water to remove the salt, and then the resulting organic layer was distilled off excess solvent such as epichlorohydrin under reduced pressure using a rotary evaporator. Add 500 parts of methyl isobutyl ketone to the residue, dissolve, add 17 parts of 30% by weight aqueous sodium hydroxide solution under stirring, react for 1 hour, and then wash with water until the washing water of the oil layer becomes neutral. From the obtained solution, 195 parts of the epoxy resin (EP1) of the present invention was obtained by distilling off methyl isobutyl ketone and the like under reduced pressure using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin is 211 g / eq. The melt viscosity (ICI melt viscosity cone # 1) at a softening point of 71 ° C. and 150 ° C. was 0.34 Pa · s.

Example 1
To 211 parts of the epoxy resin (EP1) obtained in Synthesis Example 1, 139 parts of 2,2-bis (4-cyanatephenyl) propane (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter referred to as BisA-OCN) is mixed. Further, 356 parts of methyl ethyl ketone was added and stirred at 40 ° C. for 10 minutes to obtain a liquid having an appropriate viscosity. Further, 6 parts of an imidazole catalyst (2E4MZ, manufactured by Shikoku Kasei) was added to this adjustment liquid, and the mixture was further stirred at 40 ° C. for 5 minutes to obtain a resin sheet and / or prepreg composition as an adjustment liquid (A). A glass cloth 1037 (Asahi Kasei Co., Ltd.) cut to A4 size was impregnated into this adjustment liquid, and after excess resin liquid was dropped, it was dried at 180 ° C. for 5 minutes to obtain a prepreg. There was no problem in the appearance including the smoothness of the surface of the obtained prepreg. The color became a light red-brown sheet. The exothermic onset peak by DSC was 129 ° C., confirming that the sheet was curable.

Example 2
Five prepregs obtained in Example 1 were stacked and formed with a hot plate press for 15 minutes at a pressure of 10 kg / cm ² to obtain a substrate-like plate. The obtained substrate-like plate was further post-cured at 175 ° C. for 1 hour and 220 ° C. for 1 hour to obtain a firmly cured laminate. The cured physical properties were measured with the obtained laminate. The obtained cured sheet was not confirmed to have a peak of heat generation by DSC at 200 ° C. or less, and could be judged to be sufficiently cured.

Example 3
The adjustment liquid (A) was applied to a 35 micron copper foil (rough surface) and dried at 175 ° C. for 5 minutes to obtain a copper-clad resin sheet.

Example 4
The obtained resin sheet with copper was formed with a hot plate press at a pressure of 10 kg / cm ² for 15 minutes to obtain a substrate-like plate. The obtained board-like board was further post-cured at 175 ° C. for 1 hour and 220 ° C. for 1 hour to obtain a board with copper foil.

Example 5
Two sheets of the copper-clad resin sheet obtained in Example 3 and the prepreg obtained in Example 1 were stacked and formed with a hot plate press for 15 minutes at a pressure of 10 kg / cm ² to obtain a copper-clad laminate. It was. The obtained substrate-like plate was further post-cured at 175 ° C. for 1 hour and 220 ° C. for 1 hour to obtain a firmly cured laminate.

Example 6
The prepreg obtained in Example 1 was formed as it was with a hot plate press for 15 minutes at a pressure of 10 kg / cm ² to obtain a substrate-like plate. The obtained board-like board was further post-cured at 175 ° C. for 1 hour and 220 ° C. for 1 hour to obtain a firmly cured printed wiring board board. The cured physical properties were measured on the obtained substrate. The results are shown in Table 1.
The obtained cured sheet did not have an exothermic start peak due to DSC at 200 ° C. or less, and was judged to be sufficiently cured.

Comparative Example 1
In Example 1, instead of BisA-OCN, the comparative phenol resin (KAYAHARD, GPH-103, hereinafter referred to as “PN1”) was changed to 231 parts, and 120 ° C. for 5 minutes in the solvent drying step during preparation of the prepreg. A prepreg was prepared in the same manner as described above, and then cured in the same manner as in Example 6 to produce a printed wiring board board. The results are shown in Table 1.

・ＰＮ１：水酸基当量２３６、軟化点１０２℃のビフェニルアラルキル型フェノール（日本化薬（株）製、 ＫＡＹＡＨＡＲＤ ＧＰＨ−１０３）
・ＢｉｓＡ−ＯＣＮ：2,2-ビス(4-シアネートフェニル)プロパン（東京化成（株）製）

PN1: Biphenyl aralkyl type phenol having a hydroxyl group equivalent of 236 and a softening point of 102 ° C. (manufactured by Nippon Kayaku Co., Ltd., KAYAHARD GPH-103)
・ BisA-OCN: 2,2-bis (4-cyanatephenyl) propane (manufactured by Tokyo Chemical Industry Co., Ltd.)

From Table 1, it can be confirmed that the printed wiring board made of the epoxy resin composition of the present invention has higher heat resistance than Comparative Example 1, and has a very high elastic modulus at high temperature. It was.

Claims (9)

The epoxy resin represented by the following general formula (1), an aromatic cyanate ester compound having two or more cyanato groups in the molecule , and a curing accelerator are essential components,
The curing accelerator is an imidazole or a metal compound,
The compounding amount of the epoxy resin with respect to the functional group equivalent of the cyanate ester compound is 0.1 to 1.4 equivalent,
The epoxy resin composition whose compounding quantity of the hardening accelerator with respect to 100 weight part of epoxy resins is 0.1-5.0 weight part .

(In the formula, the ratio of (a) and (b) is (a) / (b) = 1 to 3. G represents a glycidyl group. N is the number of repetitions and is 0 to 5.) A prepreg obtained by impregnating a fiber base material with the epoxy resin composition according to claim 1. The prepreg according to claim 2, wherein the fiber material is a glass fiber substrate. The prepreg as described in any one of Claim 2 or Claim 3 in which the said glass fiber base material contains at least 1 type chosen from the group which consists of T glass, S glass, E glass, NE glass, and quartz glass. A metal-clad laminate in which a metal foil is laminated on at least one surface of the prepreg according to any one of claims 2 to 4. The resin sheet formed by forming the insulating layer which consists of an epoxy resin composition of Claim 1 on a film or metal foil. A printed wiring board comprising the metal-clad laminate according to claim 5 as a circuit board. A printed wiring board formed by curing the prepreg according to any one of claims 2 to 4 and / or the resin sheet according to claim 6. A semiconductor device in which a semiconductor element is mounted on the printed wiring board according to claim 7.