JP5918943B2 - Manufacturing method of semiconductor package - Google Patents

Description

  The present invention relates to a method for manufacturing a semiconductor package.

As a method for manufacturing a semiconductor package, Patent Document 1 discloses a method for reducing damage to a semiconductor chip by performing thermocompression treatment, but it is sufficient for further development of semiconductor package downsizing and thinning. I couldn't say that it was a good technique. Moreover, although the method of suppressing the package curvature of a semiconductor package is described in Patent Document 2, complicated work such as a transfer molding technique is required.

JP 2009-267344 A JP 2002-348352 A

  The problem to be solved by the present invention is to provide a semiconductor package manufacturing method capable of suppressing package warpage even when the circuit board is thin.

As a result of intensive studies to solve the above problems, the inventors of the present invention have (A layer) a heat-resistant film layer, (B layer) a resin composition layer for a sealing layer, and (C layer) a specific circuit board layer. The present invention was completed by thermally curing the semiconductor package precursor and peeling off the A layer.

That is, the present invention includes the following contents.
[1] A method for manufacturing a semiconductor package having a package warpage of 0.1 μm to 235 μm, comprising the following steps 1 and 2.
<Step 1>
(A layer) heat resistant film layer,
(B layer) Resin composition layer for sealing layer,
(C layer) circuit board layer,
In order,
A step of thermosetting a semiconductor package precursor in which the thickness of the A layer is 1 to 100 μm, the thickness of the B layer is 100 to 600 μm, and the thickness of the C layer is 1 to 100 μm;
<Step 2>
The process of peeling A layer.
[2] The method for producing a semiconductor package according to [1], wherein the B layer in the semiconductor package precursor is formed of a sealing layer resin paste or a sealing layer adhesive sheet.
[3] The method for producing a semiconductor package according to [1] or [2], wherein the A layer in the semiconductor package precursor is laminated on the B layer.
[4] The method for producing a semiconductor package as described in [1] above, wherein the A layer and the B layer in the semiconductor package precursor are formed by a two-layer adhesive sheet.
[5] The method of manufacturing a semiconductor package as described in [1] above, wherein the package warp after the reflow treatment is 0.1 μm to 360 μm.
[6] The method for manufacturing a semiconductor package as described in [1] above, wherein when the thickness of the C layer is 1, the thickness of the B layer is in the range of 0.05 to 10.
[7] The method for manufacturing a semiconductor package as described in [1] above, wherein when the thickness of the C layer is 1, the thickness of the A layer is in the range of 0.05 to 2.
[8] A semiconductor package manufactured by any one of the methods [1] to [7].

By thermally curing a specific semiconductor package precursor containing (A layer) heat-resistant film layer, (B layer) sealing resin layer, (C layer) circuit board layer, and peeling A layer, Even when the circuit board is thin, it is possible to provide a method for manufacturing a semiconductor package that can suppress package warpage.

The present invention is a method for manufacturing a semiconductor package having a package warpage of 0.1 μm to 235 μm, comprising the following steps 1 and 2.
<Step 1>
(A layer) heat resistant film layer,
(B layer) Resin composition layer for sealing layer,
(C layer) circuit board layer,
In order,
A step of thermosetting a semiconductor package precursor in which the thickness of the A layer is 1 to 100 μm, the thickness of the B layer is 100 to 600 μm, and the thickness of the C layer is 1 to 100 μm;
<Step 2>
The process of peeling A layer.

<Process 1> Thermosetting process A semiconductor package precursor has (A layer) heat-resistant film layer, (B layer) sealing resin composition layer, (C layer) circuit board layer in order, B The layer is sealed so as to cover the semiconductor element on the C layer.

[(A layer) heat-resistant film layer]
The A layer of the present invention can be used without particular limitation, and includes various plastic films such as polyethylene naphthalate, polyphenylene sulfide, polyether ether ketone, polyimide film, polyether imide film, and liquid crystal polymer film. Moreover, you may use metal foils, such as copper foil and aluminum foil. Specifically, “Upilex-S” manufactured by Ube Industries, Ltd. “Kapton” manufactured by Toray DuPont Co., Ltd. “Apical” manufactured by Kaneka Co., Ltd., and Kuraray Co., Ltd. as liquid crystal polymer films. “Bexster” manufactured by Furukawa Circuit Foil Co., Ltd. and “electrolytic copper foil F2-WS” are available as copper foil.

The heat-resistant film may be subjected to surface treatment such as mud treatment or corona treatment. The release treatment may be performed with a release agent such as a silicone resin release agent, an alkyd resin release agent, or a fluororesin release agent.

The glass transition temperature of the A layer of the present invention is preferably 80 ° C. or higher, more preferably 90 ° C. or higher, and further preferably 100 ° C. or higher in order to reduce package warpage. Moreover, although the upper limit of glass transition temperature is not specifically limited, 300 degreeC or less is preferable and 280 degreeC or less is more preferable from a practical viewpoint.

The “glass transition temperature” here is a value indicating heat resistance, and is determined according to the method described in JIS K 7179. Specifically, thermal mechanical analysis (TMA), dynamic mechanical analysis (DMA). It is measured using etc. Examples of thermomechanical analysis (TMA) include TMA-SS6100 (manufactured by Seiko Instruments Inc.), TMA-8310 (manufactured by Rigaku Corporation), and the like. Examples of dynamic mechanical analysis (DMA) include: And DMS-6100 (manufactured by Seiko Instruments Inc.). Further, when the glass transition temperature is higher than the decomposition temperature and the glass transition temperature is not actually observed, the decomposition temperature can be regarded as the glass transition temperature in the present invention. The decomposition temperature here is defined as a temperature at which the mass reduction rate when measured according to the method described in JIS K 7120 is 5%.

The thickness of the A layer of the present invention is preferably 1 μm or more, more preferably 3 μm or more, further preferably 5 μm or more, still more preferably 10 μm or more, even more preferably 15 μm or more, particularly preferably 20 μm or more, from the viewpoint of improving the package warpage prevention effect. Is particularly preferred. Further, from the viewpoint of cost reduction and improvement of the package warpage prevention effect, it is preferably 100 μm or less, more preferably 90 μm or less, still more preferably 80 μm or less, still more preferably 70 μm or less, and particularly preferably 60 μm or less.

The average thermal expansion coefficient of the A layer of the present invention is preferably 45 ppm or less, more preferably 40 ppm or less, still more preferably 35 ppm or less, still more preferably 30 ppm or less, and even more preferably 25 ppm or less, in order to reduce package warpage. 20 ppm or less is particularly preferable. Further, from a practical viewpoint, 4 ppm or more is preferable, 5 ppm or more is more preferable, 6 ppm or more is further preferable, 7 ppm or more is further more preferable, 8 ppm or more is particularly preferable, 9 ppm or more is particularly preferable, and 10 ppm or more is particularly preferable.

The elastic modulus of the A layer of the present invention is preferably 1 GPa or more, more preferably 1.5 GPa or more, further preferably 2 GPa or more, and even more preferably 2.5 GPa or more in order to reduce package warpage. The upper limit is not particularly limited but is preferably 100 GPa or less.

[(B layer) Resin composition layer for sealing layer]
The layer B of the present invention can be obtained using a thermosetting resin composition and can be used without particular limitation as long as it is suitable for an insulating layer of a semiconductor package, and (a) one containing an epoxy resin is preferable. (A) An epoxy resin, (b) a curing agent, and (c) an inorganic filler are more preferable.

{(A) Epoxy resin}
The epoxy resin is not particularly limited, but is bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, naphthol. Type epoxy resin, naphthalene type epoxy resin, naphthylene ether type epoxy resin, glycidylamine type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin having butadiene structure, alicyclic type Epoxy resin, heterocyclic epoxy resin, phosphorus-containing epoxy resin, spiro ring-containing epoxy resin, cyclohexanedimethanol type epoxy resin, trimethylol type epoxy resin, halogenated epoxy Shi resins. These may be used alone or in combination of two or more.

Among these, bisphenol A type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, naphthylene ether type epoxy resin, butadiene structure from the viewpoint of improving heat resistance, insulation reliability, and fluidity An epoxy resin having is preferable. Specifically, for example, bisphenol A type epoxy resin (“Epicoat 828EL”, “YL980” manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resin (“jER806H”, “YL983U” manufactured by Mitsubishi Chemical Corporation), Naphthalene type bifunctional epoxy resin (“HP4032”, “HP4032D”, “HP4032SS” manufactured by DIC Corporation), naphthalene type tetrafunctional epoxy resin (“HP4700”, “HP4710” manufactured by DIC Corporation), naphthol type epoxy resin (“ESN-475V” manufactured by Nippon Steel Chemical Co., Ltd.), epoxy resin having a butadiene structure (“PB-3600” manufactured by Daicel Chemical Industries, Ltd.), epoxy resin having a biphenyl structure (Nippon Kayaku Co., Ltd.) "NC3000H", "NC3000L", "NC3100", manufactured by Mitsubishi Chemical Corporation “YX4000”, “YX4000H”, “YX4000HK”, “YL6121”), anthracene type epoxy resin (“YX8800” manufactured by Mitsubishi Chemical Corporation), naphthylene ether type epoxy resin (“EXA-7310” manufactured by DIC Corporation) , “EXA-7311”, “EXA-7311L”, “EXA7311-G3”), phosphorus-containing epoxy resin (“FX289”, “FX305”, “TX0712” manufactured by Nippon Steel Chemical Co., Ltd.), Mitsubishi Chemical Corporation “YL7613”) and the like.

Two or more epoxy resins may be used in combination, but it is preferable to contain an epoxy resin having two or more epoxy groups in one molecule. Also, an epoxy resin that is an aromatic epoxy resin that has two or more epoxy groups in one molecule and is liquid at a temperature of 20 ° C., and three or more epoxy groups in one molecule has a temperature of 20 ° C. And an embodiment containing a solid aromatic epoxy resin is more preferable. In addition, the aromatic epoxy resin as used in the field of this invention means the epoxy resin which has an aromatic ring structure in the molecule | numerator. When using a liquid epoxy resin and a solid epoxy resin together as an epoxy resin, when using the resin composition in the form of an adhesive film, the resin composition has an appropriate flexibility and the cured product of the resin composition has an appropriate breaking strength. From the point of having, the compounding ratio (liquid epoxy resin: solid epoxy resin) is preferably in the range of 1: 0.1 to 2, more preferably in the range of 1: 0.3 to 1.8, and 1: A range of 0.6 to 1.5 is more preferable.

In the thermosetting resin composition used in the present invention, from the viewpoint of improving the mechanical strength and water resistance of the cured product of the resin composition, when the nonvolatile component in the resin composition is 100% by mass, The content is preferably 3 to 40% by mass, more preferably 5 to 35% by mass, and still more preferably 10 to 30% by mass.

{(B) Curing agent}
(B) Although it does not specifically limit as a hardening | curing agent, A phenol type hardening | curing agent, a naphthol type hardening | curing agent, an active ester type hardening | curing agent, a benzoxazine type hardening | curing agent, a cyanate ester type hardening | curing agent, an acid anhydride type hardening | curing agent etc. are mentioned. Of these, phenol-based curing agents, naphthol-based curing agents, and active ester-based curing agents are preferred. These may be used alone or in combination of two or more.

  The phenolic curing agent and the naphtholic curing agent are not particularly limited, and examples thereof include a phenolic curing agent having a novolak structure and a naphtholic curing agent having a novolac structure, such as a phenol novolac resin, a triazine skeleton-containing phenol novolac resin, Naphthol novolac resins, naphthol aralkyl type resins, triazine skeleton-containing naphthol resins, and biphenyl aralkyl type phenol resins are preferred. Commercially available products include “MEH-7700”, “MEH-7810”, “MEH-7851”, “MEH7851-4H” (Maywa Kasei Co., Ltd.), “GPH” (Nippon Kasei) (Manufactured by Yakuhin Co., Ltd.), as naphthol novolak resin, “NHN”, “CBN” (manufactured by Nippon Kayaku Co., Ltd.), and as naphthol aralkyl type resin, “SN170”, “SN180”, “SN190”, “SN475” , “SN485”, “SN495”, “SN395”, “SN375” (manufactured by Nippon Steel Chemical Co., Ltd.), “TD2090” (manufactured by DIC Corporation) as a phenol novolac resin, and a phenol novolac resin “LA3018” containing a triazine skeleton. ”,“ LA7052 ”,“ LA7054 ”,“ LA1356 ”(manufactured by DIC Corporation), etc. It is. These may be used alone or in combination of two or more.

  Although there is no restriction | limiting in particular as an active ester type hardening | curing agent, Generally ester groups with high reaction activity, such as phenol ester, thiophenol ester, N-hydroxyamine ester, ester of heterocyclic hydroxy compound, are in 1 molecule. A compound having two or more in the above is preferably used. The active ester curing agent is preferably obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxy compound (preferably an active ester curing agent obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound is more preferred. Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid, etc. Examples of the phenol compound or naphthol compound include hydroquinone, resorcinol. Bisphenol A, bisphenol F, bisphenol S, phenol phthaline, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, -Naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadienyl di Examples thereof include phenol, phenol novolac, etc. The active ester curing agent can be used singly or in combination of two or more active ester curing agents disclosed in JP-A-2004-277460. A commercially available active ester-based curing agent includes those containing a dicyclopentadienyl diphenol structure, acetylated phenol novolacs, and the like. Phenol novolak benzoylates are preferred, and those containing a dicyclopentadienyl diphenol structure are more preferable, specifically, EXB9451, EXB9460, EXB9460S-65T as those containing a dicyclopentadienyl diphenol structure. , HPC-8000-65T (manufactured by DIC Corporation, active group equivalent of about 223), DC808 as an acetylated product of phenol novolac (manufactured by Mitsubishi Chemical Co., Ltd., active group equivalent of about 149), YLH1026 as a benzoylated product of phenol novolac ( Mitsubishi Chemical Corporation, active group equivalent of about 200), YLH1030 (Mitsubishi Chemical Corporation, active group equivalent of about 201), YLH1048 (Mitsubishi Chemical Corporation, active group equivalent of about 245), and the like. Among them, EXB9460S is the storage stability of varnish. From the viewpoints of the thermal expansion coefficient and the thermal expansion coefficient of the cured product.

More specifically, examples of the active ester curing agent containing a dicyclopentadienyl diphenol structure include those represented by the following formula (1).

(In the formula, R is a phenyl group or a naphthyl group, k represents 0 or 1, and n is 0.05 to 2.5 on the average of repeating units.)

From the viewpoint of improving heat resistance, R is preferably a naphthyl group, while k is preferably 0 and n is preferably 0.25 to 1.5.

  Although there is no restriction | limiting in particular as a benzoxazine type hardening | curing agent, As a specific example, Fa, Pd (made by Shikoku Kasei Co., Ltd.), HFB2006M (made by Showa Polymer Co., Ltd.), etc. are mentioned.

Although there is no restriction | limiting in particular as cyanate ester type hardening | curing agent, Novolac type (phenol novolak type, alkylphenol novolak type, etc.) cyanate ester type hardening agent, dicyclopentadiene type cyanate ester type hardening agent, bisphenol type (bisphenol A type, bisphenol) Fate, bisphenol S type, etc.) cyanate ester curing agents, and prepolymers in which these are partially triazines. Although the weight average molecular weight of a cyanate ester hardening | curing agent is not specifically limited, 500-4500 are preferable and 600-3000 are more preferable. Specific examples of the cyanate ester curing agent include, for example, bisphenol A dicyanate, polyphenol cyanate (oligo (3-methylene-1,5-phenylene cyanate), 4,4′-methylenebis (2,6-dimethylphenyl cyanate), 4,4′-ethylidenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1-bis (4-cyanatephenylmethane), bis (4-cyanate-3, Bifunctional cyanate resins such as 5-dimethylphenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, bis (4-cyanatephenyl) ether , Phenol novolac, Examples thereof include polyfunctional cyanate resins derived from resole novolac, dicyclopentadiene structure-containing phenol resins, prepolymers in which these cyanate resins are partially triazines, and these may be used alone or in combination of two or more. Examples of commercially available cyanate ester resins include phenol novolac polyfunctional cyanate ester resins represented by the following formula (2) (Lonza Japan Co., Ltd., PT30, cyanate equivalent 124), and the following formula (3): Prepolymer (part Lona Japan Co., Ltd., BA230, cyanate equivalent 232), dicyclopentadiene represented by the following formula (4): a part or all of the bisphenol A dicyanate represented by triazine Structure-containing cyanate ester resin (Lonza Japan Co., Ltd., T-4000, DT-7000), and the like.

[In formula, n shows arbitrary numbers (preferably 0-20) as an average value. ]

(In formula, n represents the number of 0-5 as an average value.)

The acid anhydride curing agent is not particularly limited, but phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic acid anhydride Hydrogenated methyl nadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid Acid anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, biphenyl tetracarboxylic dianhydride, naphthalene tetracarboxylic dianhydride, oxydiphthalic dianhydride, 3,3 ' -4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,3,3 , 4,5,9b-Hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-C] furan-1,3-dione, ethylene glycol bis (anhydrotrimellitate) ), And polymer type acid anhydrides such as styrene / maleic acid resin in which styrene and maleic acid are copolymerized.

In the resin composition used in the present invention, from the viewpoint of improving the mechanical strength and water resistance of the cured product of the resin composition, (A) the total number of epoxy groups of the epoxy resin and (E) the reactive group of the curing agent The ratio with respect to the total number is preferably 1: 0.2 to 2, more preferably 1: 0.3 to 1.5, and still more preferably 1: 0.4 to 1. The total number of epoxy groups of the epoxy resin present in the resin composition is a value obtained by dividing the solid content mass of each epoxy resin by the epoxy equivalent for all epoxy resins, and the reactive group of the curing agent. The total number of is a value obtained by adding the values obtained by dividing the solid mass of each curing agent by the reactive group equivalent for all curing agents.

{(C) Inorganic filler}
(C) The inorganic filler is not particularly limited. For example, silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, Examples thereof include aluminum borate, barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, and calcium zirconate. Of these, silica is preferable. In addition, silica such as amorphous silica, pulverized silica, fused silica, crystalline silica, synthetic silica, and hollow silica is preferable, and fused silica is more preferable. Further, the silica is preferably spherical. You may use these 1 type or in combination of 2 or more types.

The average particle size of the inorganic filler is not particularly limited, but the upper limit of the average particle size of the inorganic filler is, in the case of a semiconductor package having a narrow wire interval, the particles of the inorganic filler contact the wire, From the viewpoint of preventing the occurrence of wire flow, it is preferably 20 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less. On the other hand, the lower limit of the average particle size of the inorganic filler is set to 0. 0 from the viewpoint of preventing the viscosity of the varnish from increasing and handling properties from being lowered when the epoxy resin composition is used as a resin composition varnish. 01 μm or more is preferable, 0.03 μm or more is more preferable, 0.05 μm or more is further preferable, 0.07 μm or more is particularly preferable, and 0.1 μm or more is particularly preferable. The average particle diameter of the inorganic filler can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, the particle size distribution of the inorganic filler can be created on a volume basis by a laser diffraction particle size distribution measuring device, and the median diameter can be measured as the average particle diameter. As the measurement sample, an inorganic filler dispersed in water by ultrasonic waves can be preferably used. As a laser diffraction type particle size distribution measuring apparatus, LA-500, 750, 950, etc. manufactured by Horiba, Ltd. can be used.

  When the inorganic filler is blended, the content varies depending on the properties required of the resin composition when the nonvolatile component in the resin composition is 100% by mass, but it is preferably 20 to 85% by mass. 30 to 80% by mass is more preferable, 40 to 75% by mass is further preferable, and 50 to 70% by mass is still more preferable. If the content of the inorganic filler is too small, the coefficient of thermal expansion of the cured product tends to be high, and if the content is too large, the cured product tends to be brittle.

Inorganic fillers are epoxy silane coupling agents, amino silane coupling agents, mercapto silane coupling agents, silane coupling agents, organosilazane compounds, titanate coupling agents as long as the effects of the present invention are not impaired. What was surface-treated with a surface treating agent such as can be used. You may use these 1 type or in combination of 2 or more types. Specific examples of the surface treatment agent include aminopropylmethoxysilane, aminopropyltriethoxysilane, ureidopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, and N-2 (aminoethyl) aminopropyltrimethoxysilane. Aminosilane coupling agents such as glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, glycidoxypropylmethyldiethoxysilane, glycidylbutyltrimethoxysilane, (3,4-epoxycyclohexyl) ethyltrimethoxy Epoxysilane coupling agents such as silane, mercaptosilane coupling agents such as mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, methyltrimethoxysilane, octade Silane coupling agents such as siltrimethoxysilane, phenyltrimethoxysilane, methacroxypropyltrimethoxysilane, imidazolesilane, triazinesilane, hexamethyldisilazane, hexaphenyldisilazane, trisilazane, cyclotrisilazane, 1,1, Organosilazan compounds such as 3,3,5,5-hexamethylcyclotrisilazane, butyl titanate dimer, titanium octylene glycolate, diisopropoxy titanium bis (triethanolaminate), dihydroxy titanium bis lactate, dihydroxy bis (ammonium lactate) Titanium, bis (dioctyl pyrophosphate) ethylene titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, tri-n-butoxy titanium Nostearate, tetra-n-butyl titanate, tetra (2-ethylhexyl) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl- 1-butyl) bis (ditridecyl) phosphite titanate, isopropyl trioctanoyl titanate, isopropyl tricumyl phenyl titanate, isopropyl triisostearoyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tri (dioctyl phosphate) Titanate, isopropyltridodecylbenzenesulfonyl titanate, isopropyltris (dioctyl) Irohosufeto) titanate, isopropyl tri (N- amidoethyl-aminoethyl) titanate coupling agents such as titanates.

{(D) Curing accelerator}
(D) Although it does not specifically limit as a hardening accelerator, An amine hardening accelerator, a guanidine hardening accelerator, an imidazole hardening accelerator, a phosphonium hardening accelerator, a metal hardening accelerator, etc. are mentioned. These may be used alone or in combination of two or more.

The amine curing accelerator is not particularly limited, but trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6, -tris (dimethylaminomethyl). And amine compounds such as phenol and 1,8-diazabicyclo (5,4,0) -undecene (hereinafter abbreviated as DBU). You may use these 1 type or in combination of 2 or more types.

Although it does not specifically limit as a guanidine type hardening accelerator, Dicyandiamide, 1-methyl guanidine, 1-ethyl guanidine, 1-cyclohexyl guanidine, 1-phenyl guanidine, 1- (o-tolyl) guanidine, dimethyl guanidine , Diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo [4.4.0] dec-5-ene, 7-methyl-1,5,7-triazabicyclo [4.4.0] Deca-5-ene, 1-methyl biguanide, 1-ethyl biguanide, 1-n-butyl biguanide, 1-n-octadecyl biguanide, 1,1-dimethyl biguanide, 1,1-diethyl biguanide 1-cyclohexyl biguanide, 1-allyl biguanide, 1-phenyl Rubiguanido, 1-(o-tolyl) biguanide, and the like. You may use these 1 type or in combination of 2 or more types.

The imidazole curing accelerator is not particularly limited, but 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1- Cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium tri Meritate 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [ 2'-undecylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1')]-ethyl-s-triazine 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxy Methylimidazole, 2-phenyl-4-methyl-5hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 1 Examples include imidazole compounds such as -dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, 2-phenylimidazoline, and adducts of imidazole compounds and epoxy resins. You may use these 1 type or in combination of 2 or more types.

Although it does not specifically limit as a phosphonium type hardening accelerator, Triphenylphosphine, a phosphonium borate compound, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4- Methylphenyl) triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, and the like. You may use these 1 type or in combination of 2 or more types.

In the thermosetting resin composition used in the present invention, the content of the curing accelerator (excluding the metal-based curing accelerator) is 0.005 to 1 when the nonvolatile component in the resin composition is 100% by mass. The range of mass% is preferable, and the range of 0.01 to 0.5 mass% is more preferable. If it is less than 0.005% by mass, curing tends to be slow and a long thermosetting time is required, and if it exceeds 1% by mass, the storage stability of the resin composition tends to decrease.

Although it does not specifically limit as a metal type hardening accelerator, The organometallic complex or organometallic salt of metals, such as cobalt, copper, zinc, iron, nickel, manganese, tin, is mentioned. Specific examples of the organometallic complex include organic cobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organic copper complexes such as copper (II) acetylacetonate, and zinc (II) acetylacetonate. Organic zinc complexes such as iron (III) acetylacetonate, organic nickel complexes such as nickel (II) acetylacetonate, and organic manganese complexes such as manganese (II) acetylacetonate. Examples of the organic metal salt include zinc octylate, tin octylate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate. These may be used alone or in combination of two or more.

In the thermosetting resin composition used in the present invention, the addition amount of the metal-based curing accelerator is such that the metal content based on the metal-based curing catalyst is 25 when the nonvolatile component in the resin composition is 100% by mass. The range of ˜500 ppm is preferable, and the range of 40 to 200 ppm is more preferable. If it is less than 25 ppm, the curability of the resin composition tends to be insufficient, and if it exceeds 500 ppm, the storage stability and insulation of the resin composition tend to be lowered.

{(E) Thermoplastic resin}
(E) Examples of thermoplastic resins include phenoxy resins, polyimide resins, polyamideimide resins, polyetherimide resins, polysulfone resins, polyethersulfone resins, polyphenylene ether resins, polycarbonate resins, polyetheretherketone resins, and polyester resins. Can do. These thermoplastic resins may be used alone or in combination of two or more. The weight average molecular weight of the thermoplastic resin is preferably in the range of 5,000 to 200,000. If it is smaller than this range, the effects of improving the film forming ability and the mechanical strength tend not to be exhibited sufficiently. If it is larger than this range, the compatibility with the cyanate ester resin and naphthol type epoxy resin tends to be insufficient. In addition, the weight average molecular weight in this invention is measured by the gel permeation chromatography (GPC) method (polystyrene conversion). Specifically, the weight average molecular weight by the GPC method is LC-9A / RID-6A manufactured by Shimadzu Corporation as a measuring device, and Shodex K-800P / K-804L / K manufactured by Showa Denko KK as a column. -804L can be measured at a column temperature of 40 ° C. using chloroform or the like as a mobile phase, and can be calculated using a standard polystyrene calibration curve.

Specific examples of the phenoxy resin include, for example, FX280, FX293, ERF001 manufactured by Nippon Steel Chemical Co., Ltd., YX8100 manufactured by Mitsubishi Chemical Corporation, YL6954, YL6794, YL7213, YL6794, YL7553, YL7482 and the like. The polyvinyl acetal resin is preferably a polyvinyl butyral resin, and specific examples of the polyvinyl acetal resin include those manufactured by Denki Kagaku Kogyo Co., Ltd., Electric Butyral 4000-2, 5000-A, 6000-C, 6000-EP, Sekisui Chemical Co., Ltd. ) Made S-Rec BH series, BX series, KS series, BL series, BM series and the like. Specific examples of the polyimide include polyimide “Rika Coat SN20” and “Rika Coat PN20” manufactured by Shin Nippon Rika Co., Ltd. Also, a linear polyimide obtained by reacting a bifunctional hydroxyl group-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride (as described in JP 2006-37083 A), a polysiloxane skeleton-containing polyimide (JP 2002-2002). And modified polyimides such as those described in JP-A No. 12667 and JP-A No. 2000-319386. Specific examples of the polyamide imide include polyamide imides “Bilomax HR11NN” and “Bilomax HR16NN” manufactured by Toyobo Co., Ltd. In addition, modified polyamideimides such as polysiloxane skeleton-containing polyamideimides “KS9100” and “KS9300” manufactured by Hitachi Chemical Co., Ltd. may be mentioned. Specific examples of polyethersulfone include polyethersulfone “PES5003P” manufactured by Sumitomo Chemical Co., Ltd. Specific examples of polysulfone include polysulfone “P1700” and “P3500” manufactured by Solven Advanced Polymers, Inc.

  When (e) a thermoplastic resin is blended with the thermosetting resin composition used in the present invention, the content of the thermoplastic resin in the resin composition is not particularly limited, but the resin composition 0.1-30 mass% is preferable with respect to 100 mass% of non volatile matters in a thing, and 1-10 mass% is more preferable. If the thermoplastic resin content is too small, the effect of improving the film forming ability and mechanical strength tends not to be exhibited. If the content is too large, the melt viscosity of the resin composition increases, and the semiconductor package has a narrow filling region such as an overhang. If present, voids may be generated due to unfilling, and if the wire interval is narrow, defects such as wire flow may be caused.

{(F) Rubber particles}
(F) The rubber particles are, for example, insoluble in the organic solvent used when preparing the varnish of the resin composition, and incompatible with the cyanate ester resin and epoxy resin which are essential components. Accordingly, the rubber particles exist in a dispersed state in the varnish of the resin composition of the present invention. Such rubber particles are generally prepared by increasing the molecular weight of the rubber component to a level at which it does not dissolve in an organic solvent or resin and making it into particles.

  Preferable examples of rubber particles that can be used in the thermosetting resin composition include core-shell type rubber particles, cross-linked acrylonitrile butadiene rubber particles, cross-linked styrene butadiene rubber particles, and acrylic rubber particles. The core-shell type rubber particles are rubber particles having a core layer and a shell layer. For example, a two-layer structure in which an outer shell layer is made of a glassy polymer and an inner core layer is made of a rubbery polymer, or Examples include a three-layer structure in which the outer shell layer is made of a glassy polymer, the intermediate layer is made of a rubbery polymer, and the core layer is made of a glassy polymer. The glassy polymer layer is made of, for example, a polymer of methyl methacrylate, and the rubbery polymer layer is made of, for example, a butyl acrylate polymer (butyl rubber). Two or more rubber particles may be used in combination. Specific examples of the core-shell type rubber particles include Staphyloid AC3832, AC3816N, IM-401 modified 1, IM-401 modified 7-17 (trade name, manufactured by Ganz Kasei Co., Ltd.), Metabrene KW-4426 (trade name, Mitsubishi) Rayon Co., Ltd.). Specific examples of the crosslinked acrylonitrile butadiene rubber (NBR) particles include XER-91 (average particle size: 0.5 μm, manufactured by JSR Corporation). Specific examples of the crosslinked styrene butadiene rubber (SBR) particles include XSK-500 (average particle size 0.5 μm, manufactured by JSR Corporation). Specific examples of the acrylic rubber particles include Methbrene W300A (average particle size 0.1 μm) and W450A (average particle size 0.2 μm) (manufactured by Mitsubishi Rayon Co., Ltd.).

  The average particle diameter of the rubber particles to be blended is preferably in the range of 0.005 to 1 μm, more preferably in the range of 0.2 to 0.6 μm. The average particle diameter of the rubber particles used in the present invention can be measured using a dynamic light scattering method. For example, rubber particles are uniformly dispersed in an appropriate organic solvent by ultrasonic waves, etc., and a particle size distribution of rubber particles is created on a mass basis using a concentrated particle size analyzer (FPAR-1000; manufactured by Otsuka Electronics Co., Ltd.). And it can measure by making the median diameter into an average particle diameter.

  The content of the rubber particles is preferably 1 to 10% by mass, and more preferably 2 to 5% by mass with respect to 100% by mass of the nonvolatile content in the resin composition.

{(G) Flame retardant}
(G) Examples of the flame retardant include an organic phosphorus flame retardant, an organic nitrogen-containing phosphorus compound, a nitrogen compound, a silicone flame retardant, and a metal hydroxide. Examples of organic phosphorus flame retardants include phenanthrene-type phosphorus compounds such as HCA, HCA-HQ, and HCA-NQ manufactured by Sanko Co., Ltd., and phosphorus-containing benzoxazine compounds such as HFB-2006M manufactured by Showa High Polymer Co., Ltd. Reefos 30, 50, 65, 90, 110, Fine Techno Co., TPP, RPD, BAPP, CPD, TCP, TXP, TBP, TOP, KP140, TIBP, TPPO, PPQ, manufactured by Hokuko Chemical Co., Ltd. Phosphoric ester compounds such as OP930 manufactured by Clariant Co., Ltd., PX200 manufactured by Daihachi Chemical Co., Ltd., and organic nitrogen-containing phosphorus compounds include phosphoric ester amides such as SP670 and SP703 manufactured by Shikoku Kasei Kogyo Co., Ltd. Compounds such as SPB100, SPE100 manufactured by Otsuka Chemical Co., Ltd., FP-series manufactured by Fushimi Pharmaceutical Co., Ltd. Sufazen compounds. As the metal hydroxide, magnesium hydroxide such as UD65, UD650, UD653 manufactured by Ube Materials Co., Ltd., B-30, B-325, B-315, B-308 manufactured by Sakai Kogyo Co., Ltd. Examples thereof include aluminum hydroxide such as B-303 and UFH-20.

{Other ingredients}
In the resin composition used in the present invention, other components can be blended as necessary within a range not inhibiting the effects of the present invention. Other components include vinyl benzyl compounds, acrylic compounds, maleimide compounds, thermosetting resins such as blocked isocyanate compounds, organic fillers such as silicon powder, nylon powder and fluorine powder, thickeners such as Orben and Benton, Silicone-based, fluorine-based, polymer-based antifoaming or leveling agents, imidazole-based, thiazole-based, triazole-based, silane-based coupling agents, etc., phthalocyanine blue, phthalocyanine green, iodin green, Examples thereof include colorants such as disazo yellow and carbon black.

  The method for preparing the thermosetting resin composition for the B layer of the present invention is not particularly limited. For example, the above-described blending components may be mixed with a rotary mixer or the like by adding a solvent or the like as necessary. Is mentioned.

The thickness of B layer means the thickness of the contact direction of B layer and C layer, and the perpendicular direction of the contact surface of B layer and A layer. The thickness of the B layer is preferably 100 μm or more, more preferably 150 μm or more, and further preferably 200 μm or more, from the viewpoint of sufficiently embedding the semiconductor element as much as the thickness of the semiconductor element. Moreover, from a viewpoint of thickness reduction of a semiconductor package, 600 micrometers or less are preferable, 500 micrometers or less are more preferable, and 400 micrometers or less are still more preferable.

The elastic modulus of the sealing layer when the B layer is thermally cured to form a sealing layer is preferably 6 GPa or more, more preferably 7 GPa or more, still more preferably 8 GPa or more, and 9 GPa in order to reduce package warpage. The above is still more preferable, 10 GPa or more is particularly preferable, and 11 GPa or more is particularly preferable. Further, from the viewpoint of improving substrate machinability after sealing, it is preferably 25 GPa or less, more preferably 23 GPa or less, further preferably 21 GPa or less, particularly preferably 19 GPa or less, and particularly preferably 17 GPa or less.

The relationship between the elastic modulus of the A layer and the elastic modulus of the sealing layer is such that the elastic modulus of the sealing layer is 0.1 to 6 when the elastic modulus of the A layer is 1 from the viewpoint of reducing package warpage. Is preferably in the range of 0.3 to 5, more preferably in the range of 0.5 to 4.

The average thermal expansion coefficient of the sealing layer when the B layer is thermally cured to form a sealing layer is preferably 100 ppm or less, more preferably 90 ppm or less, and still more preferably 80 ppm or less, in order to reduce package warpage. 70 ppm or less, still more preferably 60 ppm or less, even more preferably 50 ppm or less, particularly preferably 40 ppm or less, particularly preferably 35 ppm or less. Moreover, 4 ppm or more is preferable from a practical viewpoint, 5 ppm or more is more preferable, 6 ppm or more is further more preferable, 7 ppm or more is still more preferable, and 8 ppm or more is especially preferable.

[(C layer) circuit board layer]
The “circuit board layer” in the present invention is not particularly limited, and examples thereof include a glass epoxy board, a metal board, a polyester board, a polyimide board, a BT resin board, and a thermosetting polyphenylene ether board. The thickness of the circuit board layer is preferably 100 μm or less, more preferably 90 μm or less, still more preferably 80 μm or less, and even more preferably 70 μm or less, from the viewpoint of miniaturization of the semiconductor package. From the viewpoint of reducing package warpage, it is preferably 10 μm or more, more preferably 20 μm or more, still more preferably 30 μm or more, and even more preferably 40 μm or more.

From the viewpoint of reducing package warpage, the relationship between the thickness of the C layer and the thickness of the A layer is preferably in the range of 0.05 to 2 when the thickness of the C layer is 1. , 0.08 to 1.8, more preferably 0.11 to 1.6, even more preferably 0.14 to 1.4, and The range of 17 to 1.2 is even more preferable, and the range of 0.2 to 1 is even more preferable.

From the viewpoint of reducing package warpage, the relationship between the thickness of the C layer and the thickness of the B layer is preferably in the range of 0.05 to 10 when the thickness of the C layer is 1. , Preferably in the range of 0.1-9, more preferably in the range of 1-8, even more preferably in the range of 2-7, and even more preferably in the range of 3-6. .

[Method of manufacturing semiconductor package precursor]
The semiconductor package precursor is obtained by forming the B layer on the C layer and further forming the A layer on the B layer.
{Method for producing layer B}
First, a method for forming the B layer will be described. B layer of this invention can be formed with the resin paste for sealing layers, or the adhesive sheet for sealing layers. For example, there is a method in which a B layer is formed by directly applying a resin paste for sealing layer onto the C layer and drying it. As another forming method, there is a method of forming a B layer by laminating an adhesive sheet for a sealing layer on a C layer. Describe these methods in detail

(Aspect 1) B layer forming method using resin paste for sealing layer A thermosetting resin composition is dissolved in an organic solvent to produce a resin paste for a sealing layer. If the thermosetting resin composition is a resin composition having a low viscosity, it can be used as it is as a resin paste. Subsequently, B layer is formed on C layer by a screen printing process using the resin paste for sealing layers. In the case of no solvent, drying after printing may not be performed. As another method, the B layer is formed by a transfer molding process using a resin paste for a sealing layer.

(Aspect 2) B layer forming method using adhesive sheet for sealing layer A resin varnish prepared by dissolving a thermosetting resin composition in an organic solvent is prepared, and this resin varnish is used using an apparatus such as a bar coater or a die coater. Then, it is applied to a support, and the organic solvent is dried by heating or hot air blowing to form a B layer on the support to produce an adhesive sheet for a sealing layer. Next, the sealing layer adhesive sheet is opposed to the C layer, laminated, and the B layer is formed on the C layer. After lamination, the support is peeled off.

Examples of the organic solvent for preparing the resin paste or resin varnish include ketones such as acetone, methyl ethyl ketone, and cyclohexanone, and acetates such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate. Carbitols such as cellosolve and butyl carbitol, aromatic hydrocarbons such as toluene and xylene, amide solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone. Two or more organic solvents may be used in combination.

 As a support for producing an adhesive sheet, a film of polyolefin such as polyethylene, polypropylene, polyvinyl chloride, a film of polyester such as polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”) or polyethylene naphthalate, Various plastic films such as polycarbonate film can be mentioned. The support and a protective film described later may be subjected to surface treatment such as mud treatment or corona treatment. The release treatment may be performed with a release agent such as a silicone resin release agent, an alkyd resin release agent, or a fluororesin release agent. Although the thickness of a support body is not specifically limited, 10-150 micrometers is preferable and 25-50 micrometers is more preferable.

In the adhesive sheet, a protective film according to the support can be further laminated on the surface where the support is not in close contact. Although the thickness of a protective film is not specifically limited, For example, it is 1-40 micrometers. By laminating the protective film, it is possible to prevent adhesion or scratches of dust or the like to the surface of the sealing resin composition layer. The adhesive sheet can also be stored in a roll form.

The drying conditions for preparing the adhesive sheet are not particularly limited, but the drying is performed so that the content of the organic solvent in the resin composition layer for a sealing layer is 10% by mass or less, preferably 5% by mass or less. Depending on the amount of organic solvent in the varnish and the boiling point of the organic solvent, for example, by drying a varnish containing 30 to 60% by mass of an organic solvent at 50 to 150 ° C. for 3 to 10 minutes, a resin composition for a sealing layer A layer can be formed.

{Method for producing layer A}
Next, a method for forming the A layer will be described. After forming the B layer on the C layer by the method of the above aspect 1 or 2, the A layer is formed on the B layer. The A layer can be formed by laminating a heat resistant film on the B layer.

{Method for forming double-layer adhesive sheet}
A two-layer adhesive sheet in which an A layer and a B layer are laminated in advance can also be used. Specifically, a resin varnish can be applied on the A layer, and the organic solvent can be dried by heating or hot air blowing to form the B layer on the A layer to produce a two-layer adhesive sheet. . Also, a two-layer adhesive sheet can be produced by laminating the heat-resistant film and the B layer of the sealing layer adhesive sheet. The B layer surface of the two-layer adhesive sheet is laminated on the C layer.

{Screen printing process}
When the resin paste is screen-printed, the viscosity of the resin paste is preferably 20 Pa · S / 25 ° C. to 40 Pa · S / 25 ° C. In order to suppress the generation of voids after screen printing, the loss on heating is desirably 5% or less. After printing, the organic solvent is dried at 50 to 150 ° C. for 10 to 60 minutes.

{Transfer molding process}
This step is a step of transfer molding the resin paste, placing the circuit board in the mold, pouring the resin paste, molding at 170 to 190 ° C. for 1 to 5 minutes, and releasing from the mold after molding. .

{Lamination process}
In this process, the sealing layer adhesive sheet is arranged so that the resin surface of the sealing layer adhesive sheet faces the surface on which the semiconductor elements of the circuit board are laminated so as to cover the semiconductor elements on the circuit board layer. It is a process of placing on a circuit board and laminating on a circuit board by heating and pressing through an elastic material under reduced pressure. Or it is the process of laminating | stacking by arrange | positioning a heat-resistant film and the resin composition layer for sealing layers facing each other, and heating and pressurizing through an elastic material under reduced pressure. Under reduced pressure is an atmosphere in which the air pressure is reduced to 20 mmHg (26.7 hPa) or less. In the laminating process, heating and pressurization can be performed by pressing a heated metal plate such as a SUS mirror plate from the support side. However, instead of directly pressing the metal plate, it is applied to the semiconductor element on the circuit board. Pressing is performed through an elastic material such as heat-resistant rubber so that the sealing layer sufficiently follows. The temperature of the press is preferably 70 to 140 ° C. (more preferably 80 to 130 ° C.), and the pressure is preferably 1 to 11 kgf / cm ² (9.8 × 10 ^{4 to} 107.9 × 10 ⁴ N / m ² ). It is done in the range.

The laminating step can be continuously performed by a commercially available vacuum laminator. Examples of the commercially available vacuum laminator include a vacuum pressure laminator manufactured by Meiki Seisakusho, a vacuum applicator manufactured by Nichigo Morton, and the like.

{Step of peeling the support}
This step is a step of peeling the support after laminating the sealing layer adhesive sheet on the circuit board. The support may be peeled off manually or mechanically by an automatic peeling device. The support is peeled before the step of forming the heat-resistant film layer.

[Thermosetting process]
This step is a thermosetting step in which the B layer is thermoset to form a sealing layer that is an insulating layer. From the viewpoint of preventing thermal decomposition of the resin composition, the thermosetting temperature is preferably 250 ° C. or lower, more preferably 240 ° C. or lower, further preferably 230 ° C. or lower, still more preferably 220 ° C. or lower, and 210 ° C. or lower. Particularly preferred is 200 ° C. or less. Further, from the viewpoint of sufficiently curing the resin composition, 150 ° C. or higher is preferable, 160 ° C. or higher is more preferable, and 170 ° C. or higher is even more preferable. The time for thermosetting is preferably 300 minutes or less, more preferably 180 minutes or less, still more preferably 120 minutes or less, even more preferably 110 minutes or less, and even more preferably 100 minutes or less from the viewpoint of preventing thermal decomposition of the resin composition. Particularly preferred. Further, from the viewpoint of sufficiently curing the resin composition, it is preferably 30 minutes or longer, more preferably 60 minutes or longer, still more preferably 70 minutes or longer, and even more preferably 80 minutes or longer. This step is performed after the screen printing step, transfer molding step, or laminating step.

The thickness of the insulating layer is basically the thickness of the resin composition layer for the sealing layer. Therefore, the thickness of the insulating layer is preferably 100 to 600 μm, more preferably 150 to 500 μm, and still more preferably 200 to 400 μm. The thickness of the insulating layer can also be measured with a microscope or the like in a cross-sectional view after curing.

Further, the semiconductor element is disposed on the C layer, and the B layer is sealed so as to cover the semiconductor element on the C layer. The thickness of the semiconductor element is preferably 300 μm or less, more preferably 250 μm or less, and even more preferably 200 μm or less from the viewpoint of reducing the thickness of the semiconductor package. Moreover, from a viewpoint of fully exhibiting performance, 50 micrometers or more are preferable and 100 micrometers or more are more preferable.

<Step 2> Stripping Step After the semiconductor package precursor is thermally cured, the semiconductor package can be obtained by stripping the A layer. In this step, the same method as the step of peeling the support can be used. Specifically, the heat-resistant film may be peeled manually or mechanically by an automatic peeling device. Good. When a metal foil is used as the heat resistant film, it may be removed by etching with an etching solution.

The package warp value after the step of peeling off the A layer is preferably 235 μm or less, more preferably 220 μm or less, still more preferably 200 μm or less, still more preferably 180 μm or less, even more preferably 160 μm or less, from the viewpoint of improving mountability. 150 μm or less is particularly preferable, 140 μm or less is particularly preferable, and 130 μm or less is even more preferable. On the other hand, the lower limit of the package warp value is preferably 0.1 μm or more, more preferably 5 μm or more, still more preferably 10 μm or more, and even more preferably 20 μm or more, from the viewpoint of practicality.

Further, the package warp value after the reflow treatment at a peak temperature of 260 ° C. for 10 seconds or more is preferably 360 μm or less, more preferably 330 μm or less, still more preferably 310 μm or less, and further preferably 250 μm, from the viewpoint of improving mountability on a printed wiring board. The following is still more preferable, 220 μm or less is particularly preferable, 220 μm or less is particularly preferable, 200 μm or less is particularly preferable, and 170 μm or less is even more preferable. On the other hand, the lower limit of the package warp value is preferably 0.1 μm or more, more preferably 5 μm or more, still more preferably 10 μm or more, and even more preferably 20 μm or more, from the viewpoint of practicality.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the following description, “part” means “part by mass”.

[Measurement and evaluation methods]
First, various measurement methods and evaluation methods will be described.

[Thickness measurement]
The heat-resistant film layer, the support, and the resin composition layer for the sealing layer used in Examples and Comparative Examples were measured using a contact-type layer thickness meter (manufactured by Mitutoyo Corporation, MCD-25MJ). The resin composition layer for the sealing layer is obtained by subtracting the value of the thickness of the heat-resistant film layer from the value of the thickness of the two-layer adhesive sheet, or the value of the thickness of the support from the value of the thickness of the adhesive sheet for the sealing layer. Calculated by subtraction.

[Measurement and evaluation of package warpage]
The semiconductor packages obtained in the examples and comparative examples were diced to 2.1 cm × 1.6 cm, and the package warpage of the semiconductor packages was measured at room temperature. The measurement was performed in accordance with JEITA ED-7306 of the Japan Electronics and Information Technology Industries Association standard using a shadow moiré measuring device (Thermoire AXP: manufactured by Akrometrix). Specifically, a virtual plane calculated by the least square method of all data of the substrate surface in the measurement region is set as a reference plane, the maximum value in the vertical direction from the reference plane is A, and the minimum value is B The value of A | + | B | (Coplanarity) was taken as the package warpage value and evaluated as follows.
A: Less than 100 μm B: 100 μm or more and less than 150 μm
Δ: 150 μm or more and less than 240 μm x: 240 μm or more.

[Measurement and evaluation of package warpage after reflow]
The semiconductor packages obtained in the examples and comparative examples were diced to 2.1 cm × 1.6 cm, and the package warpage of the semiconductor package after the reflow treatment was measured at room temperature. The measurement was performed in accordance with JEITA ED-7306 of the Japan Electronics and Information Technology Industries Association standard using a shadow moiré measuring device (Thermoire AXP: manufactured by Akrometrix). Specifically, a virtual plane calculated by the least square method of all data of the substrate surface in the measurement region is set as a reference plane, the maximum value in the vertical direction from the reference plane is A, and the minimum value is B The value of A | + | B | (Coplanarity) was taken as the package warpage value and evaluated as follows.
A: Less than 160 μm B: 160 μm or more and less than 260 μm
Δ: 260 μm or more and less than 365 μm ×: 365 μm or more

[Measurement of average thermal expansion coefficient and glass transition temperature]
The adhesive sheets obtained in the examples and comparative examples were thermally cured by heating at 180 ° C. for 90 minutes, and a sheet-like cured product was obtained by peeling the PET film. The cured product was cut into a test piece having a width of about 5 mm and a length of about 15 mm, and thermomechanical analysis was performed by a tensile load method using a thermomechanical analyzer TMA-SS6100 (manufactured by Seiko Instruments Inc.). . After mounting the test piece on the apparatus, the test piece was measured twice continuously under the measurement conditions of a load of 1 g and a heating rate of 5 ° C./min. The average coefficient of thermal expansion (ppm) from 25 ° C. to 150 ° C. in the second measurement was calculated. The glass transition temperature (° C.) was calculated from the point at which the slope of the dimensional change signal in the second measurement changed.

[Measurement of elastic modulus]
The adhesive sheets obtained in the examples and comparative examples were thermally cured by heating at 180 ° C. for 90 minutes, and a sheet-like cured product was obtained by peeling the PET film. The cured product is cut into a test piece having a width of about 7 mm and a length of about 40 mm, and dynamic mechanical analysis is performed in a tensile mode using a dynamic mechanical analyzer DMS-6100 (manufactured by Seiko Instruments Inc.). It was. After mounting the test piece on the apparatus, measurement was performed under the measurement conditions of a frequency of 1 Hz and a heating rate of 5 ° C / min. The storage elastic modulus (E ′) value at 25 ° C. in this measurement was read.

<Production Example 1>
19 parts of liquid bisphenol A type epoxy resin (epoxy equivalent 180, “Epicoat 828EL” manufactured by Mitsubishi Chemical Corporation) and 43 parts of naphthalene type tetrafunctional epoxy resin (epoxy equivalent 163, “HP4700” manufactured by DIC Corporation) While stirring, the mixture was dissolved in 31 parts of MEK and 31 parts of cyclohexanone with stirring. Thereto, a phenolic curing agent having a novolak structure (“LA7052” manufactured by DIC Corporation, MEK solution having a solid content of 60 wt%, phenolic hydroxyl group equivalent 120), phenoxy resin (molecular weight 50000, Mitsubishi Chemical Corporation) ) "E1256" MEK solution with a nonvolatile content of 40 wt%) 8 parts, curing catalyst (Shikoku Kasei Kogyo Co., Ltd., "2E4MZ") 0.1 part, spherical silica (SOC2) 320 parts are mixed, high speed A resin varnish 1 was prepared by uniformly dispersing with a rotary mixer.

<Production Example 2>
40 parts of polyimide resin (Ajinomoto Fine Techno Co., Ltd., “T2”), diethylene glycol monoethyl ether acetate (hereinafter referred to as EDGAc) of bisphenol A novolac type epoxy resin and ipsol 150 (aromatic hydrocarbon-based mixed solvent: Idemitsu Petrochemical Co., Ltd.) mixed varnish (solid content 75% by weight, epoxy equivalent 210, Mitsubishi Chemical Co., Ltd. “157S70”) 9.5 parts, phenol novolac resin (DIC Corporation “TD2090”, A MEK solution having a solid content of 60% by weight, 2.1 parts of phenolic hydroxyl group equivalent 105), 0.1 part of an imidazole derivative (“P200H50” manufactured by Mitsubishi Chemical Corporation), and 15 parts of spherical silica (SOC2) The mixture was mixed and uniformly dispersed with a high-speed rotary mixer to prepare a resin varnish 2.

<Production Example 3>
23.5 parts of liquid bisphenol A type epoxy resin (epoxy equivalent 180, "Epicoat 828EL" manufactured by Mitsubishi Chemical Corporation) and 20 parts of naphthalene type tetrafunctional epoxy resin (epoxy equivalent 163, "HP4700" manufactured by DIC Corporation) Were dissolved in a mixture of 17 parts of MEK and 17 parts of cyclohexanone with stirring. Thereto, a phenolic curing agent having a novolak structure (“LA7054” manufactured by DIC Corporation, MEK solution having a solid content of 60 wt%, phenolic hydroxyl group equivalent 125), 31 parts, phenoxy resin (molecular weight 50000, Mitsubishi Chemical Corporation) ) "E1256" manufactured by MEK solution having a nonvolatile content of 40 wt%) 20 parts, curing catalyst (Shikoku Kasei Kogyo Co., Ltd., "2E4MZ") 0.15 parts, spherical silica (SOC2) 50 parts are mixed, and high speed A resin varnish 3 was prepared by uniformly dispersing with a rotary mixer.

<Example 1>
(Manufacture of double-layer adhesive sheet)
The resin composition layer after drying has a thickness of 300 μm on the release treatment surface of a polyimide film (thickness 25 μm, “Kapton” manufactured by Toray DuPont Co., Ltd.) obtained by treating resin varnish 1 with an alkyd mold release agent. Then, a two-layer adhesive sheet was obtained by uniformly coating with a bar coater and drying at 80 to 120 ° C. (average 100 ° C.) for 7 minutes.

(Lamination and smoothing of double-layer adhesive sheet)
The two-layer adhesive sheet is placed on the side where the semiconductor element of the circuit board (semiconductor element size 2.0 cm × 1.25 cm, thickness 200 μm, core board thickness 60 μm) is mounted. The resin composition layer was laminated so as to be in contact therewith. For the laminating process, vacuum pressurization type laminator MVLP-500 manufactured by Meiki Seisakusho Co., Ltd. is used, and after vacuum suction for 30 seconds at a temperature of 100 ° C., from above the heat-resistant film under the conditions of a temperature of 120 ° C. and a pressure of 7.0 kg / cm 2. Laminate by pressing for 30 seconds through heat-resistant rubber, and then press for 60 seconds under atmospheric pressure using a SUS end plate at a temperature of 120 ° C. and a pressure of 6.0 kg / cm 2. The layer adhesive sheet was smoothed.

(Thermosetting of adhesive sheet for sealing layer)
The circuit board on which the sealing sheet adhesive sheet was laminated was thermally cured using a hot air circulating furnace at 180 ° C. for 90 minutes to form an insulating layer. Thereafter, the polyimide film was peeled off. Thus, a semiconductor package in which the semiconductor element was sealed with the insulating layer was obtained.

<Example 2>
Instead of the polyimide film treated with the alkyd release agent of Example 1 (thickness 25 μm, “Kapton” manufactured by Toray DuPont Co., Ltd.), the polyimide film treated with the alkyd release agent (thickness 50 μm, Toray) A semiconductor package was obtained in the same manner as in Example 1 except that “Kapton” manufactured by DuPont was used.

<Example 3>
Instead of using polyimide film (thickness 25 μm, “Kapton” manufactured by Toray DuPont Co., Ltd.) treated with the alkyd mold release agent of Example 1, “Bexter” (25 μm) manufactured by Kuraray Co., Ltd. was used. Obtained a semiconductor package in the same manner as in Example 1.

<Example 4>
Instead of the polyimide film (thickness 25 μm, “Kapton” manufactured by Toray DuPont Co., Ltd.) treated with the alkyd release agent of Example 1, “Electrolytic copper foil F2-WS” manufactured by Furukawa Circuit Foil Co., Ltd. ( A semiconductor package was obtained in the same manner as in Example 1 except that 12 μm) was used.

<Comparative Example 1>
A semiconductor package was obtained in the same manner as in Example 2, except that the resin varnish 2 was used instead of the resin varnish 1 in Example 2.

<Comparative Example 2>
Example 1 and Example 1 except that a PET film (38 μm) was used instead of the polyimide film (thickness 25 μm, “Kapton” manufactured by Toray DuPont Co., Ltd.) treated with the alkyd release agent of Example 1. A semiconductor package was obtained in the same manner.

<Comparative Example 3>
A semiconductor package was obtained in the same manner as in Example 2 except that the resin varnish 3 was used instead of the resin varnish 1 in Example 2.

The results are shown in Table 1.

  From the result of Table 1, since Examples 1-4 use the manufacturing method of the semiconductor package of this invention, it is a semiconductor package with few package curvature. On the other hand, Comparative Examples 1 to 3 did not use the semiconductor package manufacturing method of the present invention, and the package warpage was large.

  Even when the circuit board is thin, it is possible to provide a method for manufacturing a semiconductor package that can suppress package warpage. Furthermore, electric products such as computers, mobile phones, digital cameras, and televisions, and vehicles such as motorcycles, automobiles, trains, ships, and airplanes equipped with these can be provided.

Claims (9)

Following steps 1-2;
<Step 1>
(A layer) heat resistant film layer,
(B layer) Resin composition layer for sealing layer,
(C layer) circuit board layer,
In order,
The average thermal expansion coefficient of the A layer is 45 ppm or less,
A step of thermosetting a semiconductor package precursor in which the thickness of the A layer is 1 to 100 μm, the thickness of the B layer is 100 to 600 μm, and the thickness of the C layer is 1 to 100 μm;
<Step 2>
Peeling the A layer;
A method of manufacturing a semiconductor package, comprising:
Package warp after <Step 2> of peeling the A layer is 0.1 μm to 235 μm,
The manufacturing method of the semiconductor package whose average thermal expansion coefficient of a sealing layer is 35 ppm or less when the said B layer is thermosetted and a sealing layer is formed.   The method for producing a semiconductor package according to claim 1, wherein the B layer in the semiconductor package precursor is formed of a sealing layer resin paste or a sealing layer adhesive sheet.   The method for manufacturing a semiconductor package according to claim 1, wherein the A layer in the semiconductor package precursor is laminated on the B layer.   The method for manufacturing a semiconductor package according to claim 1, wherein the A layer and the B layer in the semiconductor package precursor are formed by a two-layer adhesive sheet. 2. The method of manufacturing a semiconductor package according to claim 1, wherein the package warp after the reflow treatment of the package after <Step 2> of peeling the A layer is 0.1 μm to 360 μm.   2. The method of manufacturing a semiconductor package according to claim 1, wherein when the thickness of the C layer is 1, the thickness of the B layer is in the range of 1 to 10.   2. The method of manufacturing a semiconductor package according to claim 1, wherein when the thickness of the C layer is 1, the thickness of the A layer is in the range of 0.05-2.   The method for manufacturing a semiconductor package according to claim 1, wherein the elastic modulus of the sealing layer when the B layer is thermally cured to form the sealing layer is 6 GPa or more. The method for manufacturing a semiconductor package according to claim 1, wherein when the B layer is thermally cured to form a sealing layer, the sealing layer has an average coefficient of thermal expansion of 35 ppm or less and an elastic modulus of 6 GPa or more.