JP2020107767A - Sealing resin composition, hollow package and method for manufacturing the same - Google Patents

Abstract

To provide a sealing technique for obtaining a package which is superior in the resistance to molding of a device provided with a hollow part and the fillability into a narrow gap.SOLUTION: A hollow package 103 includes a substrate 109, one or more devices 111 mounted on the substrate 109 and selected from a group consisting of a semiconductor device, MEMS and an electronic component, a partition wall 113 provided on the top of the substrate 109 so as to surround an outer periphery of the device 111, and a top plate 115 provided in contact with a top face of the partition wall 113 and covering the top of the device 111, and it has one or more hollow parts 117 provided therein and covered by the substrate 109, the partition wall 113 and the top plate 115. A sealing resin composition thereof is to be used for sealing the substrate 109, the partition wall 113 and the top plate 115 of the hollow package. The sealing resin composition comprises (A)an epoxy resin and (B)an inorganic filler, in which the gel time is 60 sec. or longer and 120 sec. or shorter.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sealing resin composition, a hollow package, and a method for producing the same.

As a technique related to the sealing of a semiconductor package, there is one described in Patent Document 1 (US Patent Application Publication No. 2017/0047232). In this document, a surface mounting element such as a bulk acoustic wave (BAW) filter element is mounted on the upper surface of a substrate, and the surface mounting element is covered with a sheet-shaped sealing resin composition and sealed. Is listed.

U.S. Patent Application Publication No. 2017/0047232

In the recent package development environment, the inventors of the present invention have examined the technology described in the above literature in light of the increasing demands for thinner, smaller, and narrower terminal pitches. Even when the device is sealed, it is clear that there is room for improvement in that the hollow structure is maintained stable after molding and a package with excellent filling properties in the narrow gap under the chip is obtained. It was

Therefore, the present invention provides a sealing technique for obtaining a package having excellent molding resistance of an element provided with a hollow portion and excellent filling property in a narrow gap.

According to the invention,
Board,
One or more elements selected from the group consisting of semiconductor elements, MEMS and electronic components mounted on the substrate;
A partition wall provided on the upper part of the substrate so as to surround the outer periphery of the element,
A top plate which is provided in contact with the upper surface of the partition wall and covers the upper portion of the element,
Equipped with
A resin composition for encapsulation used for encapsulating the substrate, the partition wall and the top plate in a hollow package provided with one or more closed hollow portions covered with the substrate, the partition wall and the top plate. A thing,
(A) epoxy resin, and (B) inorganic filler,
The encapsulating resin composition has a gel time of 60 seconds or more and 120 seconds or less as measured by the following condition 1.
(Condition 1) When the curing torque of the encapsulating resin composition is measured with time at a mold temperature of 175° C. using a curast meter, the measurement is started when the maximum torque value is T. Therefore, the time required for the value of the curing torque to reach 0.1 T is the gel time.

According to the present invention, there is provided a hollow package obtained by encapsulating the substrate, the partition wall, and the top plate with a cured product of the encapsulating resin composition of the present invention.

Further, according to the present invention,
The following Step 1 and Step 2:
(Step 1) A step of providing at least one closed hollow portion by forming a partition wall and a top plate made of at least one kind of organic material on a substrate (step 2). A hollow package comprising a step of compression-molding the resin composition for encapsulation according to any one of claims at a low pressure of 0.1 MPa or more and less than 5.0 MPa to resin-encapsulate the substrate, the partition wall, and the top plate. The manufacturing method of
The step 1 includes a step of mounting the element on the substrate such that at least one element selected from the group consisting of a semiconductor element, a MEMS and an electronic component is arranged in the hollow portion. A manufacturing method is provided.

According to the present invention, it is possible to provide a sealing technique for obtaining a package having excellent molding resistance of an element provided with a hollow portion and excellent filling property in a narrow gap.

It is sectional drawing which shows the structure of the structure in this embodiment. It is sectional drawing which shows the manufacturing process of the structure body in this embodiment. It is sectional drawing which shows the manufacturing process of the structure body in this embodiment. It is a figure which shows the evaluation result of the molding resistance of the structure provided with the hollow part.

Hereinafter, embodiments will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description thereof will be omitted as appropriate. Further, the drawing is a schematic view and does not necessarily match the actual dimensional ratio. Further, "X to Y" in the numerical range represents "X or more and Y or less" unless otherwise specified.

(Resin composition for sealing)
In the present embodiment, the encapsulating resin composition is used for encapsulating the substrate, the partition wall and the top plate of the hollow package, and includes the following components (A) and (B).
(A) Epoxy resin (B) Inorganic filler The hollow package includes a substrate, one or more elements selected from the group consisting of semiconductor elements, MEMS and electronic components mounted on the substrate, and an upper portion of the substrate. A partition wall provided so as to surround the outer periphery of the element, and a top plate provided in contact with the upper surface of the partition wall and covering the upper portion of the element are provided. Further, the hollow package is provided with one or more closed hollow portions covered with the substrate, the partition wall and the top plate.
The gel time of the encapsulating resin composition measured under the following condition 1 is 60 seconds or more and 120 seconds or less.
(Condition 1) When the maximum torque value when the curing torque of the encapsulating resin composition was measured over time at a mold temperature of 175° C. using a curast meter, and the measurement was started, The time required for the value of the curing torque to reach 0.1T is the gel time.

In the present embodiment, by using the encapsulating resin composition having the above-mentioned configuration, the hollow portion can be stably maintained even when the element having the hollow portion is sealed. Further, it is possible to obtain a semiconductor package excellent in filling the narrow gap.

(Component (A))
The epoxy resin as the component (A) is specifically one or two selected from the group consisting of an epoxy resin containing two epoxy groups in the molecule and an epoxy resin containing three or more epoxy groups in the molecule. Including the above.
From the viewpoint of improving the filling characteristics of the sealing resin composition and the molding resistance of the hollow package, the component (A) is preferably a biphenylaralkyl-type epoxy resin; a triphenylmethane-type epoxy resin; a biphenyl. Type epoxy resin; and one or more selected from the group consisting of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol type epoxy resin such as tetramethylbisphenol F type epoxy resin, and more preferably biphenyl. It contains one or more selected from the group consisting of aralkyl type epoxy resin, bisphenol A type epoxy resin and bisphenol A type epoxy resin.

The content of the component (A) in the encapsulating resin composition is 100% by mass of the entire encapsulating resin composition from the viewpoint of obtaining suitable fluidity during molding and improving the filling property and moldability. When it does, it is preferably 2% by mass or more, more preferably 3% by mass or more, and further preferably 4% by mass or more.
From the viewpoint of improving the molding resistance of the hollow package 103, the content of the component (A) in the encapsulating resin composition is preferably 40 mass% when the entire encapsulating resin composition is 100 mass %. Or less, more preferably 30% by mass or less, further preferably 15% by mass or less, still more preferably 10% by mass or less.

(Component (B))
As the inorganic filler of the component (B), those generally used in resin compositions for sealing can be used. Specific examples of the inorganic filler include silica such as fused silica and crystalline silica; alumina; talc; titanium oxide; silicon nitride; aluminum nitride. These inorganic fillers may be used alone or in combination of two or more.
Among these, it is preferable that the inorganic filler contains silica, and it is more preferable to use fused silica, from the viewpoint of excellent versatility.

Regarding the size of the inorganic filler, from the viewpoint of increasing the fluidity of the encapsulating resin composition and allowing the encapsulating resin composition to be filled between the element such as a semiconductor element and the substrate without occurrence of voids or the like, The content of the undersize fraction when passing through a sieve having an opening of 20 μm is preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 100% by mass, based on the whole inorganic filler. .. Further, there is no upper limit on the content of the subsieve fraction when passing through a sieve having an opening of 20 μm, and it is 100% by mass or less.

The content of the inorganic filler in the encapsulating resin composition improves the low hygroscopicity and the low thermal expansion of the encapsulating material formed using the encapsulating resin composition, and the moisture resistance of the obtained semiconductor device is reliable. From the viewpoint of more effectively improving the heat resistance and reflow resistance, when the total amount of the encapsulating resin composition is 100% by mass, it is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably It is 80% by mass or more.
Further, the content of the entire inorganic filler in the encapsulating resin composition is the encapsulating resin composition from the viewpoint of more effectively improving the fluidity and filling property during molding of the encapsulating resin composition. When the total amount is 100 mass %, it is preferably 95 mass% or less, more preferably 93 mass% or less, and further preferably 90 mass% or less.

In the present embodiment, the sealing resin composition may include components other than the epoxy resin and the inorganic filler.
For example, the sealing resin composition may further contain a curing agent.

(Curing agent)
The curing agent can be roughly classified into three types, for example, a polyaddition type curing agent, a catalyst type curing agent, and a condensation type curing agent, and one type or two or more types thereof can be used.

Examples of the polyaddition type curing agent include aliphatic polyamines such as diethylenetriamine (DETA), triethylenetetramine (TETA) and metaxylylenediamine (MXDA), diaminodiphenylmethane (DDM), m-phenylenediamine (MPDA), In addition to aromatic polyamines such as diaminodiphenyl sulfone (DDS), polyamine compounds containing dicyandiamide (DICY), organic acid dihydrazide and the like; alicyclic acids such as hexahydrophthalic anhydride (HHPA) and methyltetrahydrophthalic anhydride (MTHPA) Acid anhydrides including aromatic acid anhydrides such as anhydrides, trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), and benzophenone tetracarboxylic acid (BTDA); phenols such as novolac type phenol resins and polyvinylphenol Resin curing agents; polymercaptan compounds such as polysulfides, thioesters and thioethers; isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; organic acids such as carboxylic acid-containing polyester resins.

Examples of the catalyst type curing agent include tertiary amine compounds such as benzyldimethylamine (BDMA) and 2,4,6-trisdimethylaminomethylphenol (DMP-30); 2-methylimidazole, 2-ethyl-4- Examples thereof include imidazole compounds such as methylimidazole (EMI24); Lewis acids such as BF ₃ complexes.

Examples of the condensation type curing agent include a phenol resin; a urea resin such as a methylol group-containing urea resin; and a melamine resin such as a methylol group-containing melamine resin.

Among these, a phenol resin curing agent is preferable from the viewpoint of improving the balance of flame resistance, moisture resistance, electrical characteristics, curability, storage stability and the like. As the phenol resin curing agent, any of monomers, oligomers and polymers having two or more phenolic hydroxyl groups in one molecule can be used, and the molecular weight and the molecular structure thereof are not limited.

Examples of the phenol resin curing agent used as the curing agent include biphenylaralkyl type phenol resin; novolac type phenol resin such as phenol novolac resin, cresol novolac resin and bisphenol novolac; polyvinylphenol; phenol hydroxybenzaldehyde resin, triphenylmethane type phenol. Resins, polyfunctional phenolic resins such as modified triphenylmethane type phenolic resins such as triphenylmethane type phenolic resins modified with formaldehyde; modified phenolic resins such as terpene modified phenolic resins and dicyclopentadiene modified phenolic resins; phenylene skeleton and/ Or aralkyl type phenol resins such as phenol aralkyl resin having a biphenylene skeleton, phenylene and/or naphthol aralkyl resin having a biphenylene skeleton; bisphenol compounds such as bisphenol A and bisphenol F, and the like. Also, two or more kinds may be used in combination. Among these, from the viewpoint of improving heat resistance and filling properties, it is more preferable to use a polyfunctional phenol resin such as phenol/hydroxybenzaldehyde resin. From the same viewpoint, it is also preferable to use at least one selected from the group consisting of a biphenylaralkyl-based phenol resin and a triphenylmethane-type phenol resin.

In the present embodiment, the content of the curing agent in the encapsulating resin composition is such that the entire encapsulating resin composition from the viewpoint of achieving excellent fluidity during molding and improving the filling property and moldability. Is preferably 1% by mass or more, more preferably 2% by mass or more, further preferably 3% by mass or more.
In addition, regarding a semiconductor device having a cured product of the encapsulating resin composition as an encapsulant, the content of the curing agent in the encapsulating resin composition is determined from the viewpoint of improving moisture resistance reliability and reflow resistance. When the total amount of the stopping resin composition is 100% by mass, it is preferably 25% by mass or less, more preferably 15% by mass or less, still more preferably 10% by mass or less.

The encapsulating resin composition may contain components other than the above-mentioned components, for example, a coupling agent, a curing accelerator, a fluidity imparting agent, a release agent, an ion scavenger, a low stress component, a flame retardant. , One or more kinds of various additives such as a colorant, an antioxidant and the like can be appropriately mixed.
Among them, the coupling agent is, for example, various silane compounds such as epoxysilane, mercaptosilane, aminosilane such as secondary aminosilane, alkylsilane, ureidosilane, vinylsilane, methacrylsilane, titanium compounds, aluminum chelates, and aluminum/zirconium compounds. One or two or more selected from known coupling agents such as
The curing accelerator is, for example, a phosphorus atom-containing compound such as an organic phosphine, a tetra-substituted phosphonium compound, a phosphobetaine compound, an adduct of a phosphine compound and a quinone compound, an adduct of a phosphonium compound and a silane compound; 1,8-diazabicyclo [5.4.0] Undecene-7, benzyldimethylamine, 2-methylimidazole and the like, one kind selected from nitrogen atom-containing compounds such as amidines and tertiary amines, quaternary salts of the above amidines and amines Alternatively, two or more kinds can be included. Among these, it is more preferable to include a phosphorus atom-containing compound from the viewpoint of improving curability. Further, from the viewpoint of improving the balance between moldability and curability, it has latent properties such as tetra-substituted phosphonium compounds, phosphobetaine compounds, adducts of phosphine compounds and quinone compounds, and adducts of phosphonium compounds and silane compounds. It is more preferable to include those.
Specific examples of the fluidity-imparting agent include 2,3-dihydroxynaphthalene.
The release agent may include, for example, natural wax such as carnauba wax, synthetic wax such as montanic acid ester wax, higher fatty acid such as zinc stearate and metal salts thereof, and one or more kinds selected from paraffin. it can.
A specific example of the ion trapping agent is hydrotalcite.
Specific examples of the low stress component include silicone oil and silicone rubber.
Specific examples of the flame retardant include aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, and phosphazene.
Specific examples of the colorant include carbon black and red iron oxide.
Specific examples of the antioxidant include hindered phenol compounds, hindered amine compounds and thioether compounds.

The gel time of the resin composition for encapsulation measured under the following condition 1 is excellent in moldability of the hollow portion of the element encapsulated with the cured product of the resin composition for encapsulation and the filling property in a narrow gap. From the viewpoint of obtaining an excellent package, it is 60 seconds or more, more preferably 70 seconds or more, and further preferably 80 seconds or more.
From the same viewpoint, the gel time of the encapsulating resin composition is 120 seconds or less, preferably 110 seconds or less, and more preferably 100 seconds or less.
(Condition 1) When the maximum torque value when the curing torque of the encapsulating resin composition was measured over time at a mold temperature of 175° C. using a curast meter, and the measurement was started, The time required for the value of the curing torque to reach 0.1T is the gel time.

Further, when sealing a substrate on which an element having a hollow portion and an element having no hollow portion are mixed, the gel time of the resin composition for sealing is preferably 55 seconds or more, and , Preferably 100 seconds or less.

In the present embodiment, for example, the gel time can be controlled by appropriately selecting the type and amount of each component contained in the encapsulating resin composition, the method for preparing the encapsulating resin composition, and the like. It is possible. Among these, for example, appropriately selecting an epoxy resin and appropriately selecting a compounding and adjusting method for the entire composition is an element for setting the gel time within a desired numerical range.

The spiral flow length of the encapsulating resin composition measured under the following condition 2 is excellent in molding resistance of the hollow part of the element encapsulated with the cured product of the encapsulating resin composition and is small. From the viewpoint of obtaining a package having excellent filling properties, it is preferably 100 cm or more, more preferably 150 cm or more, still more preferably 160 cm or more, still more preferably 180 cm or more.
From the same viewpoint, the spiral flow length of the encapsulating resin composition is preferably 220 cm or less, more preferably 215 cm or less, still more preferably 210 cm or less.
(Condition 2) A sealing resin composition is injected into a spiral flow measurement mold according to ANSI/ASTM D 3123-72 under conditions of a mold temperature of 175° C., an injection pressure of 6.9 MPa, and a holding time of 120 seconds. The flow length measured in this way is taken as the spiral flow length.

Further, when sealing a substrate on which an element provided with a hollow portion and an element not provided with a hollow portion are mixed, the spiral flow length of the resin composition for sealing is preferably 150 cm or more, It is more preferably 160 cm or more, preferably 215 cm or less, and more preferably 210 cm or less.

The glass transition temperature (Tg) of the cured product of the encapsulating resin composition is preferably 100° C. or higher, more preferably 110° C. or higher, and further preferably 120° C. or higher, from the viewpoint of improving the heat resistance of the cured product. Is.
The Tg of the cured product is not limited, but from the viewpoint of improving the toughness of the cured product, it is preferably 200° C. or lower, more preferably 180° C. or lower, still more preferably 160° C. or lower.
Here, the glass transition temperature of the cured product is measured with a thermomechanical analysis (TMA) device (TMA100 manufactured by Seiko Instruments Inc.) in a measurement temperature range of 0° C. to 320° C. and a heating rate of 5° C./min. It is measured under the conditions.

In this embodiment, the shape of the sealing resin composition is preferably tablet or particle. Specific examples of the particulate encapsulating resin composition include powdery or granular materials. Here, that the encapsulating resin composition is a powder or granule means that it is in the form of powder or granules.

Next, a method for producing the encapsulating resin composition will be described.
In the present embodiment, the encapsulating resin composition is, for example, a method in which the above-mentioned components are mixed by a known means, further melt-kneaded by a kneader such as a roll, a kneader or an extruder, and cooled and then pulverized. Can be obtained by The degree of dispersion, fluidity, etc. of the obtained sealing resin composition may be appropriately adjusted.
Then, in the present embodiment, a resin composition for encapsulation having a gel time within the above-mentioned specific range can be obtained by adjusting the components, the composition and the production conditions contained in the resin composition for encapsulation.

(Hollow package, structure)
Next, the hollow package and the structure including the hollow package will be described. In the present embodiment, the hollow package is obtained by sealing the substrate, the partition wall, and the top plate with the cured product of the sealing resin composition according to the present embodiment described above.
Further, in the present embodiment, the structure has a hollow package mounted on the substrate. The structure may be one in which only the hollow package is mounted on the substrate, or the hollow package and an element having no hollow portion may be mixedly mounted. When the structure includes a plurality of packages, the plurality of packages may be singulated in a post process.

FIG. 1 is a cross-sectional view showing an example of the structure of the structure according to the present embodiment. The structure 100 shown in FIG. 1 has a hollow package 103 and a package 105 mounted on a substrate 101. As the substrate 101, for example, an organic substrate such as an interposer can be used.
Both the hollow package 103 and the package 105 are sealed with a sealing material 107. The encapsulating material 107 is made of a cured product of the encapsulating resin composition according to the present embodiment described above. In FIG. 1, the sealing material 107 is provided over the entire surface of the substrate 101 on which the element is mounted.
The hollow package 103 and the package 105 will be described below.

First, the package 105 will be described. The package 105 is formed by flip-chip connecting the semiconductor element 121 to the element mounting surface of the substrate 101 by the bump 123. In the package 105, the semiconductor element 121 and the bump 123 are sealed with a sealing material 107.

Specific examples of the package 105 include QFP (Quad Flat Package), SOP (Small Outline Package), BGA (Ball Grid Array), CSP (Chip Size Package), QFN (Quad Flat Non-leaded Package), and SON (Small Outline Non). -leaded Package), LF-BGA (Lead Flame BGA), SiP (System In Package), and LGA (Land Grid Allay).

In addition, the hollow package 103 includes a substrate 109, one or more elements 111 selected from the group consisting of semiconductor elements, MEMS, and electronic components mounted on the substrate 109, and an outer periphery of the element 111 on the substrate 109. A partition 113 provided so as to surround the partition 113 and a top plate 115 provided in contact with an upper surface of the partition 113 and covering an upper portion of the element 111 are provided. The hollow package 103 is provided with at least one closed hollow portion 117 covered with a substrate 109, a partition wall 113, and a top plate 115. Then, the substrate 109, the partition wall 113, and the top plate 115 are sealed by the sealing material 107.
The hollow package 103 is flip-chip connected to the substrate 101 by bumps 119 provided on the top plate 115. Wirings (not shown) that connect the bumps 119 and the conductors on the substrate 101 may be provided over the top surface and side surfaces of the top plate 115, the side surfaces of the partition wall 113, and the top surface of the substrate 101.

The element 111 may be one or more selected from the group consisting of a semiconductor element, a MEMS and an electronic component, and is specifically an element applied to a package having a hollow structure. Specific examples of the element 111 include a high frequency filter such as a BAW filter and a surface acoustic wave (SAW) filter.

The material of the substrate 109 can be selected according to the type of the element 111 and the like. The substrate 109 may be a semiconductor substrate such as a silicon substrate. When the element 111 is a high frequency filter, the material of the substrate 109 is preferably a piezoelectric substance such as lithium tantalate (LT) or lithium niobate (LN).

The sizes of the partition 113 and the top plate 115 can be set according to the size of the element 111.
The thickness of the partition wall 113 is preferably 5 μm or more, and more preferably 7 μm or more, from the viewpoint of ensuring the hollow portion 117 around the element 111. From the viewpoint of thinning the hollow package 103, the thickness of the partition wall 113 is preferably 30 μm or less, more preferably 20 μm or less.
The width of the partition wall 113 is preferably 5 μm or more, and more preferably 20 μm or more, from the viewpoint of improving the molding resistance. From the viewpoint of miniaturization of the hollow package 103, the width of the partition wall 113 is preferably 200 μm or less, more preferably 100 μm or less.
Here, the thickness of the partition wall 113 refers to the length of the partition wall 113 in the direction perpendicular to the substrate 109, and the width of the partition wall 113 refers to the length of the partition wall 113 in the in-plane direction of the substrate 109.

The thickness of the top plate 115 is preferably 10 μm or more, and more preferably 15 μm or more, from the viewpoint of improving the molding resistance. From the viewpoint of thinning the hollow package 103, the thickness of the top plate 115 is preferably 50 μm or less, more preferably 30 μm or less.
Here, the thickness of the top plate 115 refers to the length of the top plate 115 in the direction perpendicular to the substrate 109.

The longest width of the hollow portion 117 in a cross section perpendicular to the element mounting surface of the substrate 109 is preferably 60 μm or more, more preferably 100 μm or more, from the viewpoint of ensuring the hollow portion 117 around the element 111. Further, from the viewpoint of miniaturization of the hollow package 103, the longest width of the hollow portion 117 is preferably 1000 μm or less, more preferably 800 μm or less.
As a cross-sectional shape of the hollow portion 117, for example, a rectangle can be mentioned. The planar shape of the hollow portion 117 may be, for example, a square, a rectangle, a polygon, a circle, an ellipse, or a combination thereof.

Both the partition 113 and the top plate 115 are preferably made of an organic material. The materials of the partition wall 113 and the top plate 115 may be the same or different.
When at least one of the partition wall 113 and the top plate 115 is an organic material, the organic material is preferably a photosensitive dry film resist from the viewpoint of stably forming the partition wall 113 and the top plate 115 in a simple process, A negative photosensitive dry film resist is more preferable, and a negative photosensitive dry film resist containing a photo-acid generator and an epoxy resin is more preferable.
From the same viewpoint, the partition wall 113 and the top plate 115 are preferably made of a cured product of a photosensitive resin composition. Hereinafter, the constitution of the photosensitive resin composition will be specifically described.

(Photosensitive resin composition)
As the photosensitive resin composition used for forming the partition wall 113 or the top plate 115, various photosensitive resins containing polyimide, polyamide, benzocyclobutene, polybenzoxazole, maleimide, acrylate resin, phenol resin or epoxy resin as a main component. Although the composition can be used, for example, those described in WO 2012/008472 can be used. At this time, the photosensitive resin composition preferably contains a photoacid generator and an epoxy resin.

The photoacid generator preferably contains tris(4-(4-acetylphenyl)thiophenyl)sulfonium tetrakis(pentafluorophenyl)borate, and more preferably tris(4-(4-acetylphenyl)thiophenyl)sulfonium tetrakis(penta). Fluorophenyl) borate. As tris(4-(4-acetylphenyl)thiophenyl)sulfonium tetrakis(pentafluorophenyl)borate, for example, Irgacure (registered trademark) PAG 290 manufactured by BASF can be used.

The content of the photoacid generator in the photosensitive resin composition is preferably 0.1% by mass or more, and preferably 15% by mass, with the total amount of the photoacid generator and the epoxy resin being 100% by mass. % Or less.

The epoxy equivalent of the epoxy resin is preferably 150 g/eq. from the viewpoint of reducing the curing shrinkage rate of the photosensitive resin composition. That is all. In addition, the epoxy equivalent of the epoxy resin is preferably from the viewpoint of suppressing the crosslinking density of the photosensitive resin composition from being excessively decreased and the strength and chemical resistance of the cured film, heat resistance, and crack resistance being decreased. Is 500 g/eq. It is as follows.
Here, the epoxy equivalent is measured by a method according to JIS K7236.

Further, the softening point of the epoxy resin is preferably 40° C. or higher, and more preferably 50° C. or higher from the viewpoint of suppressing mask sticking and suppressing softening at room temperature. Further, from the viewpoint of enhancing the bondability to the substrate 109, the softening point of the epoxy resin is preferably 120° C. or lower, more preferably 100° C. or lower.
Here, the softening point is measured by a method based on JIS K7234.

The epoxy resin more preferably has an epoxy equivalent in the above range and a softening point in the above range, and specific examples of the epoxy resin include EOCN-102S, EOCN-103S, EOCN-104S, EOCN-1020 and EOCN-. 4400H, EPPN-201, EPPN-501H, EPPN-502H, XD-1000, BREN-S, NER-7604, NER-7403, NER-1302, NER-7516, NC-3000H (all are trade names, Nippon Kayaku Company), Epikote 157S70 (trade name, manufactured by Mitsubishi Chemical Co., Ltd.), and EHPE3150 (trade name, manufactured by Daicel Chemical Industries, Ltd.).

Specific examples of the epoxy resin include a novolac type epoxy resin and an epoxy resin obtained by an oxidation reaction of a compound having an olefin.
In addition, as a concrete example of a preferable epoxy resin, Epicoat 157 (manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 180 to 250 g) is preferable because the cured product has high chemical resistance, plasma resistance and transparency, and the cured product has low moisture absorption. /Eq., softening point 80 to 90° C.), EPON SU-8 (trade name, manufactured by Resolution Performance Products, epoxy equivalent 195 to 230 g/eq., softening point 80 to 90° C.), etc. Novolac type epoxy resin;
NC-3000 (trade name, manufactured by Nippon Kayaku Co., epoxy equivalent 270-300 g/eq., softening point 55-75° C.) and the like biphenyl-phenol novolac type epoxy resin;
NER-7604 and NER-7403 (all are trade names, bisphenol F type epoxy resin in which part of alcoholic hydroxyl group is epoxidized, manufactured by Nippon Kayaku Co., epoxy equivalent 200 to 500 g/eq., softening point 55 to 75 C.), NER-1302 and NER-7516 (both are trade names, bisphenol A type epoxy resin in which part of alcoholic hydroxyl groups is epoxidized, manufactured by Nippon Kayaku Co., epoxy equivalent 200 to 500 g/eq., softening point). 55-75° C.) bisphenol A-type or F-type epoxy resin in which part of the alcoholic hydroxyl group is epoxidized;
Cresol novolac type epoxy resin such as EOCN-1020 (trade name, manufactured by Nippon Kayaku Co., epoxy equivalent 190-210 g/eq., softening point 55-85° C.);
Multifunctional epoxy resin such as NC-6300 (trade name, manufactured by Nippon Kayaku Co., epoxy equivalent 230 to 235 g/eq., softening point 70 to 72° C.);
An epoxy resin having at least two epoxy groups in one molecule, such as a polycarboxylic acid epoxy resin (epoxy equivalent is usually 300 to 900 g/eq.) whose production method is described in JP-A-10-97070. An epoxy resin obtained by reacting a reaction product with a compound having at least one hydroxyl group and one carboxyl group in one molecule with a polybasic acid anhydride;
Trisphenol methane type epoxy resin such as EPPN-201 (trade name, manufactured by Nippon Kayaku Co., epoxy equivalent 180 to 200 g/eq., softening point 65 to 78° C.);
EPPN-501H (trade name, manufactured by Nippon Kayaku Co., epoxy equivalent 162 to 172 g/eq., softening point 51 to 57° C.), EPPN-501HY (trade name, manufactured by Nippon Kayaku Co., epoxy equivalent 163-175 g/eq) ., softening point 57 to 63° C.), EPPN-502H (trade name, manufactured by Nippon Kayaku Co., epoxy equivalent 158 to 178 g/eq., softening point 60 to 72° C.) and the like triphenylmethane type epoxy resin;
Alicyclic epoxy resin such as EHPE3150 (trade name, manufactured by Daicel Chemical Industries, Ltd., epoxy equivalent 170 to 190 g/eq., softening point 70 to 85° C.);
Dicyclopentadiene type epoxy resin such as XD-1000 (trade name, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 245 to 260 g/eq., softening point 68 to 78° C.); and the method described in JP 2007-291263 A. An epoxy resin (epoxy equivalent is usually 400 to 900 g/eq.) which is a co-condensate obtained by the method described above.

The content of the epoxy resin in the photosensitive resin composition is preferably 85% by mass or more, with the total amount of the photoacid generator and the epoxy resin being 100% by mass, from the viewpoint of improving the molding resistance of the hollow portion 117. And preferably 99.9 mass% or less.

The photosensitive resin composition may include components other than the photo-acid generator and the epoxy resin, and specific examples of such components may include one or more types of a reactive epoxy monomer and a solvent that are miscible.
When the photosensitive resin composition contains a reactive epoxy monomer, the pattern performance can be improved. Specific examples of the reactive epoxy monomer include diethylene glycol diglycidyl ether, hexanediol diglycidyl ether, dimethylol propane diglycidyl ether, polypropylene glycol diglycidyl ether (ADEKA, ED506), trimethylol propane triglycidyl ether (ADEKA, ED505). ), trimethylolpropane triglycidyl ether (low chlorine type, manufactured by Nagase ChemteX Corp., EX321L), pentaerythritol tetraglycidyl ether, and the like. Among these, low chlorine type that has undergone a low chlorine production method or a purification step is preferable. It is a thing.
The content of the reactive epoxy monomer is preferably 10% by mass in the solid content from the viewpoint of suppressing mask sticking when the solid content of the resist is the total of the photo-acid generator, the epoxy resin and the reactive epoxy monomer. % Or less, and more preferably 7% by mass or less.
The reactive epoxy monomer in the present specification means an epoxy compound which is liquid at room temperature and has a weight average molecular weight of 1,000 or less calculated in terms of polystyrene based on the measurement result of GPC.

In addition, since the photosensitive resin composition contains a solvent, the viscosity of the photosensitive resin composition can be reduced and the coating property can be improved. As the solvent, any organic solvent usually used for inks, paints and the like can be used without limitation as long as it can dissolve each component of the photosensitive resin composition. Specific examples of the solvent include ketones such as acetone, ethylmethylketone, cyclohexanone and cyclopentanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether and the like. Glycol ethers; esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, carbitol acetate, propylene glycol monomethyl ether acetate, γ-butyrolactone; alcohols such as methanol, ethanol, cellosolve, methyl cellosolve; fats such as octane and decane Group hydrocarbons; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha and the like can be mentioned.
The content of the solvent is preferably 10% by mass or more with respect to the entire photosensitive resin composition from the viewpoint of appropriately maintaining the solubility of the main components, the volatility of the components, the liquid viscosity of the composition, and the like. , Preferably 95 mass% or less, more preferably 90 mass% or less.

Further, the photosensitive resin composition may further contain an adhesion-imparting agent from the viewpoint of improving the adhesion of the composition to the substrate. The adhesion-imparting agent is a coupling agent such as a silane coupling agent and a titanium coupling agent, preferably a silane coupling agent.
The content of the adhesion-imparting agent is preferably 15% by mass or less, and more preferably 5% by mass or less, with respect to the entire photosensitive resin composition, from the viewpoint of suppressing deterioration of the physical properties of the cured film.

The photosensitive resin composition may further contain a sensitizer from the viewpoint of absorbing ultraviolet light and donating the absorbed light energy to the photoacid generator.
Specific examples of the sensitizer include thioxanthones such as 2,4-diethylthioxanthone, and anthracene compounds having a C1 to C4 alkoxy group at the 9th and 10th positions such as 9,10-dimethoxy-2-ethylanthracene (9,10). A dialkoxy anthracene derivative). The 9,10-dialkoxyanthracene derivative may further have a substituent.
The sensitizer is more preferably 2,4-diethylthioxanthone and 9,10-dimethoxy-2-ethylanthracene.
Since the effect of the sensitizer is exhibited even in a small amount, the content thereof is, for example, more than 0% by mass, preferably 30% by mass or less, and more preferably 20% by mass with respect to the photoacid generator. % Or less.

Further, when it is necessary to reduce the influence of the ions derived from the photoacid generator, the photosensitive resin composition may further contain an ion scavenger such as an organic aluminum compound.
The amount of the ion scavenger is, for example, more than 0% by mass based on the solid content of the resist when the total of the photoacid generator, the epoxy resin, and the appropriately reactive epoxy monomer is the solid content of the resist, and preferably It is 10 mass% or less.

The photosensitive resin composition may contain various additives such as a thermoplastic resin, a colorant, a thickener, a defoaming agent and a leveling agent.
Examples of the thermoplastic resin include polyether sulfone, polystyrene, and polycarbonate.
Examples of the colorant include phthalocyanine blue, phthalocyanine green, iodin green, crystal violet, titanium oxide, carbon black and naphthalene black.
Examples of the thickener include Orben, Benton, and montmorillonite.
Examples of the defoaming agent include silicone-based, fluorine-based and polymer-based defoaming agents.
The blending amount of these additives may be appropriately selected depending on the purpose of use, but is, for example, 0.1% by mass or more and 30% by mass or less with respect to the entire photosensitive resin composition.

In addition, the photosensitive resin composition may further include an inorganic filler. Specific examples of the inorganic filler include barium sulfate, barium titanate, silicon oxide, amorphous silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide and mica powder.
The compounding ratio of the inorganic filler is, for example, more than 0 mass% in the photosensitive resin composition, and is, for example, 60 mass% or less.

From the viewpoint of improving the molding resistance of the hollow part 117, the photosensitive resin composition is preferably 0.1 part by mass or more and 15 parts by mass or less of the photoacid generator, and 85 parts by mass or more and 99.9 parts by mass of the epoxy resin. Parts or less, 1 part by mass or more and 10 parts by mass or less of a reactive epoxy monomer, and 5.8 parts by mass or more and 2090 parts by mass or less of a solvent, and if necessary, the above-mentioned adhesion imparting agent, sensitizer, ion scavenger , Thermoplastic resins, colorants, thickeners, defoamers, leveling agents and inorganic fillers may be added.

Next, a method for producing the photosensitive resin composition will be described.
In the present embodiment, the photosensitive resin composition is obtained by, for example, mixing and stirring the raw material components in a predetermined blending amount by a usual method, and if necessary, a disperser such as a dissolver, a homogenizer, or a three-roll mill. May be used for dispersion and mixing. Further, after mixing, it may be filtered using a mesh, a membrane filter or the like.

Next, the properties of the photosensitive resin composition will be described. The photosensitive resin composition can be liquid, for example.
Further, the photosensitive resin composition is preferably a dry film resist. The dry film resist is obtained by applying a photosensitive resin composition on a base film by using a roll coater, a die coater, a knife coater, a bar coater, a gravure coater, or the like, and then, for example, a drying furnace set to 45° C. or higher and 100° C. or lower. It is obtained by drying in a vacuum and removing a predetermined amount of solvent. Further, a cover film or the like may be appropriately laminated on the resist. Specific examples of the base film and the cover film which are the base material of the resist include films of polyester, polypropylene, polyethylene, TAC, polyimide and the like. These films may be release-treated with a silicone-based release treatment agent or a non-silicone-based release treatment agent.

In the present embodiment, the photosensitive resin composition and the sealing resin composition having the above-described configurations are used, respectively, and the partition wall 113 and the top plate 115 are set to have a predetermined size, thereby making the hollow package 103 hollow. It is possible to obtain the structure 100 in which the portion 117 is stably maintained and the filling property of the narrow gap between the plurality of bumps 123 is excellent.

Next, a method for manufacturing the hollow package 103 and the structure 100 including the hollow package 103 will be described. In this embodiment, the method for manufacturing the hollow package 103 includes the following steps 1 and 2.
(Step 1) A step of forming one or more closed hollow portions 117 by forming the partition wall 113 and the top plate 115 made of at least one kind of organic material on the substrate 109 (step 2) 2A in which the resin composition for encapsulation in the present embodiment is compression-molded at a low pressure of 0.1 MPa or more and less than 5.0 MPa to resin-encapsulate the substrate 109, the partition wall 113 and the top plate 115. 2A to 2D will be described more specifically. 2A to 2D are cross-sectional views showing the manufacturing process of the structure 100.

First, as shown in FIG. 2A, the element 111 is mounted on the substrate 109.
Next, as shown in FIG. 2B, a partition 113 surrounding the outer periphery of the element 111 is formed on the element mounting surface of the substrate 109 so as to be separated from the element 111, and the partition 113 covers the upper portion of the partition 113. The top plate 115 is formed and the hollow portion 117 is provided. However, as described later with reference to FIGS. 3A to 3E, in some cases, the element 111 may be mounted after the partition wall is formed, and the top plate 115 may be formed last.

The partition wall 113 and the top plate 115 having a predetermined planar shape can be formed, for example, by using the above-mentioned photosensitive resin composition and using the method described in International Publication No. 2012/008472.
Specifically, when using a liquid photosensitive resin composition, for example, a spin coater or the like is used to form the photosensitive resin composition on the substrate 109 provided with the element 111 in a thickness of, for example, 0.1 μm or more and 1000 μm or less. And then heat-treated at 60° C. or higher and 130° C. or lower for 5 minutes or longer and 60 minutes or shorter to remove the solvent to form a photosensitive resin composition layer. After that, a mask having a pattern corresponding to the planar shape of the partition wall 113 is placed, ultraviolet rays are irradiated, and heat treatment is performed at 50 °C to 130 °C for 1 minute to 50 minutes, for example. Then, the unexposed portion is developed with a developing solution, for example, at 15° C. or higher and 50° C. or lower for 1 minute or more and 180 minutes or less to form a pattern.
This is heat-treated at a temperature of, for example, 130° C. or higher and 200° C. or lower to obtain a permanent protective film. As the developing solution, for example, an organic solvent such as γ-butyrolactone, triethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, or a mixed solution of these organic solvents and water can be used. For development, a paddle type, spray type, shower type developing device may be used, and ultrasonic irradiation may be appropriately performed.
The top plate 115 can also be formed according to the above-described method after forming the partition wall 113.

When a dry film resist is used, for example, the cover film is removed, and transferred to the substrate 109 with a hand roll, a laminator, or the like at a temperature of 30° C. or higher and 100° C. or lower and a pressure of 0.05 MPa or higher and 2 MPa or lower, and a liquid Exposure, post-exposure bake, development, and heat treatment may be carried out in the same manner as in the case of the photosensitive resin composition of.
The top plate 115 can be formed after the partition wall 113 is formed, according to the method in the case of using the dry film resist described above.
By using the film-shaped photosensitive resin composition (dry film resist), the steps of coating and drying the substrate 109 can be omitted, so that the manufacturing steps of the partition wall 113 and the top plate 115 can be simplified. You can

After forming the top plate 115, bumps 119 such as solder bumps are formed at predetermined positions on the upper surface of the top plate 115, that is, the back surface of the bonding surface with the partition wall 113 (FIG. 2B).

2A and 2B show an example in which a plurality of elements 111 are mounted on the substrate 109. In this case, as shown in FIG. A plurality of packages are obtained by dividing into individual pieces.

Next, the individualized packages are flip-chip connected by bumps 119 at predetermined positions on the substrate 101. In manufacturing the structure 100, the semiconductor element 121 is flip-chip connected to the predetermined position on the substrate 101 by the bump 123 (FIG. 2D).

After that, the element mounting surface of the substrate 101 is sealed with the sealing resin composition according to the present embodiment to form the sealing material 107. At this time, the sealing material 107 is preferably formed by compression molding from the viewpoint of improving the molding resistance of the hollow package 103 and improving the filling property into a narrow gap such as between the bumps 123.
From the same viewpoint, the molding pressure in compression molding is preferably 0.1 MPa or more, more preferably 0.5 MPa or more, and preferably less than 5.0 MPa, more preferably 3.0 MPa or less, It is more preferably 2.0 MPa or less, and even more preferably 1.0 MPa or less.

Through the above steps, the structure 100 including the hollow package 103 and the package 105 can be obtained. In the present embodiment, by using a sealing resin composition containing components (A) and (B) and having a gel time within a predetermined range, low pressure molding by a compression molding method becomes possible. Accordingly, the hollow portion 117 provided in the hollow package 103 can have excellent molding resistance, and even when the bumps 123 are arranged at a narrow pitch in the package 105, the gap between the bumps 123 can be reduced. The filling characteristics can be made excellent.

Note that, in the above, the partition wall 113 and the top plate 115 are formed after the element 111 is mounted on the substrate 109, but the order of forming each member may be other than this. For example, FIGS. 3A to 3E are cross-sectional views showing another manufacturing process of the structure 110.

In the manufacturing process shown in FIGS. 3A to 3E, first, the partition wall 113 is formed at a predetermined position on the substrate 109 (FIG. 3A). After that, the element 111 is mounted on the substrate 109 so that the outer periphery thereof is surrounded by the partition wall 113 (FIG. 3B).
Next, the top plate 115 that covers the upper portion of the partition 113 is formed on the partition 113, and the hollow portion 117 is provided (FIG. 3C).
Each of these steps can be performed according to, for example, the steps described above with reference to FIGS. 2A and 2B.

Then, bumps 119 such as solder bumps are formed (FIG. 3C) according to the steps shown in FIGS. 2B and 2C, and the substrate 109 is divided into individual elements 111. By doing so, a plurality of packages are obtained (FIG. 3(d)). Then, according to the process shown in FIG. 2D, the individualized packages are flip-chip connected to predetermined positions on the substrate 101 (FIG. 3E).

The structure 100 including the hollow package 103 and the package 105 is also obtained through the above steps, and the same effects as the above-described effects are obtained.

Although the present invention has been described above based on the embodiment, the present invention is not limited to the above embodiment, and the configuration can be changed without departing from the scope of the present invention.

Hereinafter, the present embodiment will be described in detail with reference to examples and comparative examples. The present embodiment is not limited to the description of these examples.

(Example 1, Comparative Example 1)
The encapsulating resin composition of each example was prepared with the formulation shown in Table 1. Then, the filling characteristics when the element was sealed with the cured product of the obtained composition were evaluated, and the molding resistance of the hollow portion in the examples was evaluated.

First, the raw material components used in the following examples are shown.
(Epoxy resin)
Epoxy resin 1: Mixed resin of biphenylene skeleton-containing phenol aralkyl type epoxy resin (Nippon Kayaku Co., Ltd., NC3000L) and bisphenol A type epoxy resin (Javan Epoxy Resin, jER (registered trademark) YL6810) Epoxy resin 2: Biphenylene skeleton Containing phenol aralkyl type epoxy resin (Nippon Kayaku Co., NC3000L)
(Curing agent)
Curing agent 1: Biphenylene skeleton-containing phenol aralkyl type resin (MEH-7851SS, manufactured by Meiwa Kasei Co., Ltd.)
(catalyst)
Catalyst 1: Tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenyl silicate and tetraphenylphosphonium-4,4'-sulfonyldiphenolate (inorganic filler)
Inorganic filler 1: Fused spherical silica (manufactured by Micron, TS-6021) Fraction that passed through a sieve with 20 μm openings: 100% by mass

(Preparation of sealing resin composition)
Based on the formulation shown in Table 1, the raw materials of each example were kneaded using a twin-screw kneading extruder at 110° C. for 7 minutes. The obtained kneaded product was deaerated and cooled, and then ground with a grinder to obtain a granular encapsulating resin composition.

(Physical properties of sealing resin composition)
(Geltime)
The curing torque of the resin composition was measured with time at a mold temperature of 175° C. using a curast meter (JSR curast meter IVPS type, manufactured by Orientec Co., Ltd.). From the obtained measurement results, when the maximum torque value in the measurement results was T, the time (seconds) required from the start of measurement until the curing torque value reached 0.1 T was calculated as the gel time. ..

(Spiral flow)
Using a low-pressure transfer molding machine (KTS-15, manufactured by Kotaki Seiki Co., Ltd.), a mold for spiral flow measurement conforming to ANSI/ASTM D 3123-72 was used, a mold temperature of 175° C., an injection pressure of 6.9 MPa, a holding pressure. The resin composition was injected under the condition of time of 120 seconds and the flow length (cm) was measured. The spiral flow is a parameter of fluidity, and the larger the value, the better the fluidity.

(Tg)
A resin composition for sealing obtained in each example under the conditions of a mold temperature of 175° C., a molding pressure of 9.8 MPa, and a curing time of 300 seconds, using a compression molding machine (manufactured by TOWA, PMC1040). A cured product was obtained by compression molding. This cured product had a length of 10 mm, a width of 4 mm and a thickness of 4 mm.
Next, after the obtained cured product is post-cured at 175° C. for 4 hours, a thermomechanical analyzer (TMA100, manufactured by Seiko Denshi Kogyo Co., Ltd.) is used to measure temperature range of 0° C. to 320° C. and heating rate of 5° C. The measurement was performed under the condition of /min to calculate Tg.

(Evaluation)
(Charging characteristics)
On a substrate (printed wiring board provided with a copper circuit), semiconductor elements each having a thickness of 100 μm and 5 mm×5 mm were flip-chip connected by bumps. The bump material was Cu, the bump height was 50 μm, the bump diameter was 90 μm, and the pitch between the bumps was 90 μm. Six of the above semiconductor elements were adhered onto one substrate, and the surface on which the semiconductor elements were mounted faced downward, and were fixed to the upper mold by substrate fixing means. Then, a resin granule made of the encapsulating resin composition of each example is supplied into the lower mold cavity, and then a panel is molded by a compression molding machine (manufactured by TOWA) while reducing the pressure in the cavity to obtain a molded product. It was The molding conditions at this time were a mold temperature of 150° C. or 175° C., a molding pressure of 1.0 MPa or 2.0 MPa, and a curing time of 300 seconds.
The obtained molded product was not singulated, and the filling property was evaluated as it was using a microscope manufactured by keyence. With respect to the six semiconductor elements, the presence or absence of filling failure such as unfilling or voids was confirmed in the region between the bumps, and the number of the elements having the filling failure out of the six elements was defined as the filling failure occurrence rate (%).

From Table 1, the encapsulating resin composition obtained in Example 1 was excellent in filling in narrow gaps.

(Mold resistance of hollow part)
The molding resistance of the hollow portion when the structure provided with the hollow portion was sealed with the sealing resin composition of Example 1 was evaluated.

As a negative-type photosensitive dry film resist, SU-8 3000CF DFR series (trade name, manufactured by Nippon Kayaku Co., Ltd., thickness including epoxy resin and photoacid generator, etc., 20 μm (3020CF), 30 μm (3030CF) and 45 μm (3045CF) ) Each dry film resist) was used.

The structure provided with the hollow portion was formed by the following procedure. That is, a negative photosensitive dry film resist cover film is peeled off on a silicon wafer and laminated at a roll temperature of 70° C., an air pressure of 0.2 MPa, and a speed of 0.5 m/min for a predetermined number of times to obtain a predetermined thickness. The photosensitive resin composition layer of was obtained. This photosensitive resin composition layer was subjected to pattern exposure (soft contact, i-line) using an i-line exposure device (mask aligner: manufactured by Ushio Inc.). After that, a post-exposure bake is performed at 95° C. for 4 minutes on a hot plate, and a development process is performed at 23° C. for 5 minutes by a dipping method using propylene glycol monomethyl ether acetate (PGMEA) to obtain a cured resin pattern on the wafer. It was Then, it was hard-baked at 180° C. for 60 minutes using a warm air convection oven. The obtained resin pattern had a shape in which line-shaped resins having a predetermined height and width were arranged in parallel at predetermined intervals, which were used as partition walls.
Next, the cover film of the photosensitive dry film resist is peeled off on the wafer on which the partition wall is formed, and laminated for a predetermined number of times at a roll temperature of 40° C., an air pressure of 0.1 MPa, and a speed of 1.0 m/min, and the predetermined To obtain a photosensitive resin composition layer having a thickness of. Then, pattern exposure, post-exposure bake, development treatment and hard bake are performed according to the method of forming the partition wall to form a resin pattern covering the upper portion between adjacent partition walls with a predetermined width and thickness, and this is used as a top plate. did.
The sizes of the partition wall and the top plate are shown below.
Thickness of partition wall (height of void): 20 μm
Interval of partition walls (width of void): 10 to 500 μm (prepared every 10 μm)
Partition width: 30 μm
Top plate thickness: 20 μm, 30 μm or 45 μm
Width of top plate: Sum of widths of both partition walls (60 μm) added to each interval of the partition walls. 70-560 μm

A wafer on which a structure composed of a top plate and partition walls was formed was placed in a compression molding machine (manufactured by TOWA), and compression molding was performed using the sealing resin composition of Example 1 to obtain a sample. The compression molding conditions were a mold temperature of 175° C., a molding pressure of 1.0 MPa, 2.0 MPa or 3.0 MPa, and a curing time of 120 seconds.

The mold resistance of the hollow portion of the sample obtained in Example 1 was evaluated. That is, for each sample, the cross section of the hollow portion was observed with a scanning electron microscope, and the maximum displacement (Maximum cap displacement: δmax) of the top plate was measured based on the following, and a sample with δmax of less than 5 μm was regarded as acceptable.
δmax = height of the top plate surface on the bulkhead-height of the top plate surface at the midpoint of the interval between the bulkheads

FIG. 4 is a diagram showing the relationship between the forming pressure (MPa) at each top plate thickness and the maximum value (μm) of the top plate width that passed the test for δmax.

100 structure 101 substrate 103 hollow package 105 package 107 encapsulant 109 substrate 111 element 113 partition wall 115 top plate 117 hollow part 119 bump 121 semiconductor element 123 bump

Claims (9)

Board,
One or more elements selected from the group consisting of semiconductor elements, MEMS and electronic components mounted on the substrate;
A partition wall provided on the upper part of the substrate so as to surround the outer periphery of the element,
A top plate which is provided in contact with the upper surface of the partition wall and covers the upper portion of the element,
Equipped with
A resin composition for encapsulation used for encapsulating the substrate, the partition wall and the top plate in a hollow package provided with one or more closed hollow portions covered with the substrate, the partition wall and the top plate. A thing,
(A) epoxy resin, and (B) inorganic filler,
The encapsulating resin composition has a gel time of 60 seconds or more and 120 seconds or less, which is measured under the following condition 1.
(Condition 1) When the curing torque of the encapsulating resin composition is measured with time at a mold temperature of 175° C. using a curast meter, the measurement is started when the maximum torque value is T. Therefore, the time required for the value of the curing torque to reach 0.1 T is the gel time. The encapsulating resin composition according to claim 1, wherein the spiral flow length of the encapsulating resin composition measured under the following condition 2 is 100 cm or more and 220 cm or less.
(Condition 2) The resin composition for encapsulation was placed in a mold for spiral flow measurement according to ANSI/ASTM D 3123-72 under conditions of a mold temperature of 175° C., an injection pressure of 6.9 MPa, and a holding time of 120 seconds. The flow length measured by injection is the spiral flow length. The component (A) contains an epoxy resin containing one or more selected from the group consisting of an epoxy resin containing two epoxy groups in the molecule and an epoxy resin containing three or more epoxy groups in the molecule. The encapsulating resin composition according to claim 1 or 2. A hollow package formed by sealing the substrate, the partition wall, and the top plate with a cured product of the resin composition for sealing according to any one of claims 1 to 3. Both the top plate and the partition wall are made of an organic material,
The top plate has a thickness of 10 μm or more and 50 μm or less,
The thickness of the partition wall is 5 μm or more and 30 μm or less, and the width of the partition wall is 5 μm or more and 200 μm or less,
The hollow package according to claim 4, wherein the longest width of the hollow portion in a cross section perpendicular to the element mounting surface of the substrate is 60 μm or more and 1000 μm or less. The following Step 1 and Step 2:
(Step 1) A step of providing at least one closed hollow portion by forming a partition wall and a top plate made of at least one kind of organic material on a substrate (step 2). A hollow package comprising a step of compression-molding the resin composition for encapsulation according to any one of claims at a low pressure of 0.1 MPa or more and less than 5.0 MPa to resin-encapsulate the substrate, the partition wall, and the top plate. The manufacturing method of
The step 1 includes a step of mounting the element on the substrate such that at least one element selected from the group consisting of a semiconductor element, a MEMS and an electronic component is arranged in the hollow portion. Production method. The method for manufacturing a hollow package according to claim 6, wherein the organic material is a photosensitive dry film resist. The method for manufacturing a hollow package according to claim 7, wherein the organic material is a negative photosensitive dry film resist. The method for manufacturing a hollow package according to claim 8, wherein the organic material is a negative photosensitive dry film resist containing a photo-acid generator and an epoxy compound.

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