JP2014216526A - Thermosetting sealing resin sheet and method of manufacturing electronic component package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting sealing resin sheet which allows for manufacturing an electronic package having superior reliability, and to provide a method of manufacturing an electronic component package using the same.SOLUTION: A thermosetting sealing resin sheet contains 70 wt.% or more and 80 wt.% or less of an inorganic filler, and has a surface warpage of -0.6 mm or more and 0.1 mm or less, respectively, in the following heat treatment 1 and heat treatment 2. Heat treatment 1: The thermosetting sealing resin sheet is bonded onto a printed circuit board of 50 mm square having a thickness of 0.32 mm on which a silicon chip of 35 mm square having a thickness of 0.2 mm is mounted via a die bond film having a thickness of 25 μm so as to have a total thickness of 0.75 mm after bonding, thereafter it is heat treated for one hour at 150°C, and allowed to stand for one hour at 25°C as a sealed body. Heat treatment 2: The sealed body subjected to heat treatment 1 is further released into 240°C atmosphere.

Description

  The present invention relates to a thermosetting sealing resin sheet and a method for manufacturing an electronic component package.

  In recent years, there has been a further demand for higher performance, thinner and smaller semiconductor devices and their packages. As a measure for high-density integration of electronic components, a package-on-package (hereinafter referred to as “PoP”) in which a package in which electronic components such as semiconductor elements are resin-sealed on a substrate is stacked in multiple layers in the thickness direction. 3D mounting technology called “structure” has been developed. The upper and lower packages are generally electrically connected by bumps provided on the back surface (lower surface) of the upper package and electrodes provided on the upper surface of the lower package.

  Here, when a high-temperature treatment such as solder reflow is performed in the manufacturing process of the PoP structure, the substrate may be warped due to the stress generated by the difference in linear expansion coefficient between the members constituting the PoP structure. As the entire package becomes thinner, such a warp tends to become more prominent in a situation where the mounting substrate constituting the package is also made thinner. When the mounting substrate is warped, stress is concentrated particularly on the bump connection portion, and connection failure may occur.

  Technology to prevent warping of the mounting board by interposing a resin base material for stress relaxation between the upper and lower packages, particularly from the viewpoint of suppressing the difference in coefficient of linear expansion between the mounting board and the bump Has been proposed (Patent Document 1).

JP 2010-199611 A

  On the other hand, since the electronic component mounted on the substrate is in a resin-sealed state, stress is generated due to the difference in the coefficient of linear expansion between the sealing resin and the substrate, which may cause warping or sealing of the substrate. There are cases where peeling of the resin from the substrate, cracking of the sealing resin, and the like occur. In the PoP structure, almost the entire upper surface (exposed surface) is covered with a sealing resin in the upper package, whereas an electrode region for bump connection with the upper package is provided on the upper surface of the lower package. Since it is necessary to provide the peripheral portion so as to avoid the stop portion, in general, the area of the resin sealing portion of the lower package is often smaller than the resin sealing portion of the upper package. Then, in the PoP structure, not only the influence of the difference in linear expansion coefficient between the sealing resin and the substrate in each package, but also a difference in linear expansion coefficient between the upper package and the lower package is generated, and the stress difference between the two is also caused. The warp of the substrate, peeling of the sealing resin, cracks, etc. will occur. Such an event is likely to occur at the time of solder reflow or the like when multi-layer stacking of packages is performed after the sealing resin of each package is cured.

  Further, even when the electronic component is resin-sealed, the substrate may be warped due to the effect of thermosetting shrinkage of the sealing resin. As in the case of the above-described difference in linear expansion coefficient, the PoP structure causes not only the effect of thermosetting shrinkage of the sealing resin in each package, but also the difference in thermosetting shrinkage between the upper package and the lower package, The difference in stress between the two causes warpage of the substrate, peeling of the sealing resin, cracks, and the like. Such an event is likely to occur when the multi-layer stacking of packages is performed without curing the sealing resin of each package, and finally the thermosetting process is performed collectively.

  As described above, the PoP structure is affected not only by the difference in linear expansion coefficient or thermosetting shrinkage in each package, but also by the difference in linear expansion coefficient or thermosetting shrinkage between the upper and lower packages. Therefore, it becomes difficult to maintain or improve the reliability of the entire PoP structure.

  The present invention has been made in view of the above problems, and an object thereof is to provide a thermosetting encapsulating resin sheet capable of producing an electronic package having excellent reliability and a method for producing an electronic component package using the same. There is to do.

  As a result of intensive studies to solve the conventional problems, the present inventors have found that the object can be achieved by adopting the following configuration, and have completed the present invention.

That is, the thermosetting sealing resin sheet of the present invention is
Containing an inorganic filler in a content of 70 wt% to 80 wt%,
A thermosetting encapsulating resin sheet in which the amount of surface warpage in the following heat treatment 1 and heat treatment 2 is −0.6 mm or more and 0.1 mm or less, respectively.
Heat treatment 1: The thermosetting encapsulating resin sheet is placed on a 50 mm square 0.32 mm thick printed circuit board on which a 35 mm square and 0.2 mm thick silicon chip is mounted via a 25 μm thick die bond film. Bonding is performed so that the total thickness after bonding is 0.75 mm, heat treatment is performed at 150 ° C. for 1 hour to form a sealed body, and then the film is allowed to stand at 25 ° C. for 1 hour.
Heat treatment 2: The sealed body that has undergone the heat treatment 1 is put into a 240 ° C. atmosphere.

  The thermosetting encapsulating resin sheet (hereinafter also simply referred to as “encapsulating resin sheet”) has a high content of 70 wt% or more and 80 wt% or less of an inorganic filler having a lower linear expansion coefficient than the resin component. Since it contains in quantity, the linear expansion coefficient of the whole sealing resin sheet after a thermosetting process can be reduced. As a result, the linear expansion coefficient difference can be reduced even for a substrate having a low linear expansion coefficient such as a glass epoxy substrate, and the warpage of the substrate or the peeling or cracking of the sealing resin due to the linear expansion coefficient difference. Etc. (hereinafter, these defects caused by the difference in linear expansion coefficient are also referred to as “substrate warp or the like”). Moreover, in the said sealing resin sheet, content of the resin component which affects the heat shrink in the case of a thermosetting process is reduced with the high content inorganic filler. As a result, in the sealing resin sheet, since the surface warpage amount after passing through the predetermined heat treatments 1 and 2 is suppressed to −0.6 mm or more and 0.1 mm or less, the thermosetting shrinkage of the sealing resin sheet is reduced. The influence on the substrate can be sufficiently suppressed. As described above, according to the sealing resin sheet, the reliability of the entire PonP structure with respect to the high-temperature treatment can be improved even when a high-temperature treatment such as a sealing treatment or subsequent solder reflow is performed. In addition, when the sign of the surface warp amount is plus, the sealing resin sheet after the heat treatment is warped so as to be depressed toward the substrate side (see FIG. 4B), and when the sign of the surface warp amount is minus, the sealing is performed. The resin sheet is warped so as to swell to the opposite side of the substrate (see FIG. 4C). In this specification, the method for measuring the amount of surface warpage is as described in the examples.

  If the content of the inorganic filler is less than 70% by weight, warpage during solder reflow increases, and defects such as solder cracks may occur. On the other hand, when the content of the inorganic filler exceeds 80% by weight, the warping of the molded body becomes large at the resin sealing stage, which may cause problems such as conveyance failure and dicing failure.

  In the sealing resin sheet, the linear expansion coefficient after heat treatment at 150 ° C. for 1 hour is preferably 15 ppm / K or more and 30 ppm / K or less at the glass transition temperature or lower. By setting the linear expansion coefficient below the glass transition temperature of the heat-treated product after the predetermined heat treatment within the above range, even if the high-temperature treatment is performed on the PoP structure after the sealing treatment, the sealing resin sheet and particularly the low wire A difference in linear expansion coefficient from a substrate having an expansion coefficient can be reduced, and warpage of the substrate can be prevented. In addition, the measuring method of a linear expansion coefficient and a glass transition temperature is based on description of an Example.

  In the sealing resin sheet, the inorganic filler is preferably silica particles from the viewpoint of controlling the linear expansion coefficient.

  In the sealing resin sheet, the average particle diameter of the inorganic filler is preferably 0.1 μm or more and 35 μm or less. By setting the average particle size of the inorganic filler within the above range, it is possible to obtain good dispersibility of the inorganic filler and to ensure followability to unevenness on the electronic component and the substrate.

In the present invention, a preparation step of preparing a mounting substrate on which electronic components are mounted,
A laminated body forming step of forming a laminated body having a total thickness of 0.75 mm or less by laminating the thermosetting sealing resin sheet on the mounting substrate so as to cover the electronic component; and the thermosetting sealing resin The manufacturing method of the electronic component package including the sealing process of thermosetting the sheet is also included.

  In the electronic component package manufacturing method of the present invention, since the sealing resin sheet is used, even if the total thickness of one package is reduced to 0.75 mm or less, high reliability in which the warpage of the substrate is suppressed. The electronic component package can be manufactured.

  In the said manufacturing method, it is preferable to perform the said sealing process, after laminating | stacking the several laminated body obtained by repeating the said preparation process and the said laminated body formation process in multiple steps. Thereby, a highly reliable PonP structure can be efficiently manufactured.

It is a cross-sectional schematic diagram which shows the thermosetting sealing resin sheet which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows the electronic component package which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows the sample for surface curvature amount measurement after the sealing process of a thermosetting resin sealing sheet. It is a top view which shows the measurement procedure of the surface curvature amount after the sealing process of a thermosetting sealing resin sheet. It is an example of the XX sectional view of Drawing 4A. It is another example of the XX sectional view of Drawing 4A.

[First Embodiment]
A first embodiment which is an embodiment of the present invention will be described below with reference to the drawings. However, in some or all of the drawings, parts unnecessary for the description are omitted, and there are parts shown enlarged or reduced for easy explanation. First, after describing the thermosetting sealing resin sheet, a method for manufacturing an electronic component package using the thermosetting sealing resin sheet will be described.

<Thermosetting sealing resin sheet>
FIG. 1 is a cross-sectional view schematically showing a thermosetting sealing resin sheet according to an embodiment of the present invention. The sealing resin sheet 1 is typically provided in a state of being laminated on a support 1a such as a polyethylene terephthalate (PET) film. In addition, in order to perform peeling of the sealing resin sheet 1 easily, the mold release process by a well-known mold release agent may be performed to the support body 1a. Moreover, it is good also as a wound body which formed the sealing resin sheet 1 continuously on the elongate support body 1a, and wound up this in roll shape.

  In the sealing resin sheet 1, the surface warpage amount after passing through the predetermined heat treatments 1 and 2 only needs to be −0.6 mm or more and 0.1 mm or less, but the preferable lower limit is −0.5 mm or more, and more preferable. The lower limit is −0.4 mm or more. On the other hand, the preferable upper limit of the surface warp amount is 0.08 mm or less, and the more preferable upper limit is 0.05 mm or less. Since the surface warpage amount of the sealing resin sheet 1 is in the above range, the thermosetting shrinkage action at the time of resin sealing and the thermal expansion action at the time of solder reflow are suppressed, and as a result, the warpage of the substrate is suppressed. A highly reliable electronic package can be manufactured.

  The linear expansion coefficient after heat-treating the sealing resin sheet 1 at 150 ° C. for 1 hour is not particularly limited below the glass transition temperature of the sample after the heat treatment, but the lower limit is preferably 15 ppm / K or more, and 14 ppm / K or more. More preferred. The upper limit of the linear expansion coefficient is preferably 30 ppm / K or less, and more preferably 25 ppm / K or less. By setting the linear expansion coefficient below the glass transition temperature of the heat-treated product after the predetermined heat treatment within the above range, even if the high-temperature treatment is performed on the PoP structure after the sealing treatment, the sealing resin sheet and particularly the low wire A difference in linear expansion coefficient from a substrate having an expansion coefficient can be reduced, and warpage of the substrate can be prevented.

The resin composition for forming the thermosetting sealing resin sheet is not particularly limited as long as it has the above-described characteristics and can be used for resin sealing of electronic components such as semiconductor chips. For example, the following epoxy resin compositions containing A to E components are preferred. The C component may or may not be added as necessary.
A component: Epoxy resin B component: Phenol resin C component: Elastomer D component: Inorganic filler E component: Curing accelerator

(A component)
The epoxy resin (component A) is not particularly limited. For example, triphenylmethane type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, modified bisphenol A type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, modified bisphenol F type epoxy resin, dicyclopentadiene type Various epoxy resins such as an epoxy resin, a phenol novolac type epoxy resin, and a phenoxy resin can be used. These epoxy resins may be used alone or in combination of two or more.

  From the viewpoint of ensuring the toughness after curing of the epoxy resin and the reactivity of the epoxy resin, those having an epoxy equivalent of 150 to 250 and a softening point or melting point of 50 to 130 ° C. are preferably solid, and in particular, from the viewpoint of reliability. Therefore, triphenylmethane type epoxy resin, cresol novolac type epoxy resin, and biphenyl type epoxy resin are preferable.

  The content of the epoxy resin (component A) is preferably set in the range of 1 to 10% by weight with respect to the entire epoxy resin composition.

(B component)
The phenol resin (component B) is not particularly limited as long as it causes a curing reaction with the epoxy resin (component A). For example, a phenol novolak resin, a phenol aralkyl resin, a biphenyl aralkyl resin, a dicyclopentadiene type phenol resin, a cresol novolak resin, a resole resin, or the like is used. These phenolic resins may be used alone or in combination of two or more.

  From the viewpoint of reactivity with the epoxy resin (component A), it is preferable to use a phenolic resin having a hydroxyl equivalent weight of 70 to 250 and a softening point of 50 to 110 ° C., among which the curing reactivity is high. A phenol novolac resin can be preferably used. From the viewpoint of reliability, low hygroscopic materials such as phenol aralkyl resins and biphenyl aralkyl resins can also be suitably used.

  From the viewpoint of curing reactivity, the blending ratio of the epoxy resin (component A) and the phenol resin (component B) is a hydroxyl group in the phenol resin (component B) with respect to 1 equivalent of the epoxy group in the epoxy resin (component A). It is preferable to mix | blend so that it may become 0.7-1.5 equivalent, More preferably, it is 0.9-1.2 equivalent.

(C component)
The elastomer (C component) used together with the epoxy resin (component A) and the phenol resin (component B) provides the epoxy resin composition with the flexibility necessary for sealing electronic components with a thermosetting sealing resin sheet. The structure is not particularly limited as long as it exhibits such an action. For example, various acrylic copolymers such as polyacrylates, styrene acrylate copolymers, butadiene rubber, styrene-butadiene rubber (SBR), ethylene-vinyl acetate copolymer (EVA), isoprene rubber, acrylonitrile rubber, etc. Polymers can be used. Among them, it is easy to disperse in the epoxy resin (component A), and because the reactivity with the epoxy resin (component A) is high, the heat resistance and strength of the resulting thermosetting sealing resin sheet can be improved. From the viewpoint, it is preferable to use an acrylic copolymer. These may be used alone or in combination of two or more.

  The acrylic copolymer can be synthesized, for example, by radical polymerization of an acrylic monomer mixture having a predetermined mixing ratio by a conventional method. As a method for radical polymerization, a solution polymerization method in which an organic solvent is used as a solvent or a suspension polymerization method in which polymerization is performed while dispersing raw material monomers in water are used. As a polymerization initiator used in that case, for example, 2,2′-azobisisobutyronitrile, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobis-4- Methoxy-2,4-dimethylvaleronitrile, other azo or diazo polymerization initiators, peroxide polymerization initiators such as benzoyl peroxide and methyl ethyl ketone peroxide are used. In the case of suspension polymerization, it is desirable to add a dispersing agent such as polyacrylamide or polyvinyl alcohol.

  The content of the elastomer (component C) is 1 to 15% by weight of the entire epoxy resin composition. If the content of the elastomer (C component) is less than 1% by weight, it becomes difficult to obtain the flexibility and flexibility of the sealing resin sheet 1, and further the resin sealing that suppresses the warp of the thermosetting sealing resin sheet. It will be difficult to stop. On the other hand, when the content exceeds 15% by weight, the melt viscosity of the sealing resin sheet 1 is increased and the embedding property of the electronic component is lowered, and the strength and heat resistance of the cured body of the sealing resin sheet 1 are reduced. There is a tendency to decrease.

  The weight ratio of the elastomer (component C) to the epoxy resin (component A) (weight of component C / weight of component A) is preferably set in the range of 3 to 4.7. When the weight ratio is less than 3, it is difficult to control the fluidity of the sealing resin sheet 1, and when it exceeds 4.7, the adhesiveness of the sealing resin sheet 1 to electronic components tends to be inferior. Because.

(D component)
The inorganic filler (component D) is not particularly limited, and various conventionally known fillers can be used. For example, quartz glass, talc, silica (fused silica, crystalline silica, etc.), alumina, nitriding Examples thereof include aluminum, silicon nitride, and boron nitride powders. These may be used alone or in combination of two or more.

  Among these, silica powder is used in that the internal stress is reduced by reducing the coefficient of thermal expansion of the cured product of the epoxy resin composition, and as a result, warpage of the sealing resin sheet 1 after sealing of the electronic component can be suppressed. It is preferable to use a fused silica powder among the silica powders. Examples of the fused silica powder include spherical fused silica powder and crushed fused silica powder. From the viewpoint of fluidity, it is particularly preferable to use a spherical fused silica powder.

  Although the average particle diameter of the inorganic filler (component D) is not particularly limited, it is preferable to use an inorganic filler having a range of 0.1 to 35 μm, and more preferably having a range of 0.3 to 30 μm.

  The average particle diameter can be derived by using a sample arbitrarily extracted from the population and measuring it using a laser diffraction / scattering particle size distribution measuring apparatus.

  The content of the inorganic filler (component D) is preferably 70 to 80% by weight, more preferably 72 to 78% by weight, based on the total epoxy resin composition. If the content of the inorganic filler (component D) is less than 70% by weight, warpage during solder reflow increases and the possibility of poor connection between the upper and lower packages increases. On the other hand, if the content exceeds 80% by weight, the amount of warpage when heated to 150 ° C. for 1 hour and cured and then cooled to 25 ° C. increases, and the possibility of defective conveyance and dicing failure increases.

(E component)
The curing accelerator (component E) is not particularly limited as long as it allows curing of the epoxy resin and the phenol resin, but from the viewpoint of curability and storage stability, triphenylphosphine or tetraphenylphosphonium tetraphenyl. Organic phosphorus compounds such as borates and imidazole compounds are preferably used. These curing accelerators may be used alone or in combination with other curing accelerators.

  It is preferable that content of a hardening accelerator (E component) is 0.1-5 weight part with respect to a total of 100 weight part of an epoxy resin (A component) and a phenol resin (B component).

(Other ingredients)
In addition to the A component to the E component, a flame retardant component may be added to the epoxy resin composition. As the flame retardant composition, various metal hydroxides such as aluminum hydroxide, magnesium hydroxide, iron hydroxide, calcium hydroxide, tin hydroxide, and complex metal hydroxide can be used.

  The average particle diameter of the metal hydroxide is preferably 1 to 10 μm, more preferably 2 to 5 μm, from the viewpoint of ensuring appropriate fluidity when the epoxy resin composition is heated. It is. When the average particle size of the metal hydroxide is less than 1 μm, it becomes difficult to uniformly disperse in the epoxy resin composition, and the fluidity during heating of the epoxy resin composition tends to be insufficient. Moreover, since the surface area per addition amount of a metal hydroxide (E component) will become small when an average particle diameter exceeds 10 micrometers, the tendency for a flame-retardant effect to fall is seen.

  As the flame retardant component, a phosphazene compound can be used in addition to the metal hydroxide. As phosphazene compounds, for example, SPR-100, SA-100, SP-100 (above, Otsuka Chemical Co., Ltd.), FP-100, FP-110 (above, Fushimi Pharmaceutical Co., Ltd.) and the like are available as commercial products. is there.

（式（１）中、ｎは３〜２５の整数であり、Ｒ^１及びＲ^２は同一又は異なって、アルコキシ基、フェノキシ基、アミノ基、水酸基及びアリル基からなる群より選択される官能基を有する１価の有機基である。）

（式（２）中、ｎ及びｍは、それぞれ独立して３〜２５の整数である。Ｒ^３及びＲ^５は同一又は異なって、アルコキシ基、フェノキシ基、アミノ基、水酸基及びアリル基からなる群より選択される官能基を有する１価の有機基である。Ｒ^４は、アルコキシ基、フェノキシ基、アミノ基、水酸基及びアリル基からなる群より選択される官能基を有する２価の有機基である。） The phosphazene compound represented by the formula (1) or the formula (2) is preferable from the viewpoint of exhibiting a flame retardant effect even in a small amount, and the content of phosphorus element contained in these phosphanzene compounds is 12% by weight or more. Is preferred.

(In the formula (1), n is an integer of 3 to 25, R ¹ and R ² are the same or different and are selected from the group consisting of an alkoxy group, a phenoxy group, an amino group, a hydroxyl group and an allyl group. A monovalent organic group having

(In the formula (2), n and m are each independently an integer of 3 to 25. R ³ and R ⁵ are the same or different and are composed of an alkoxy group, a phenoxy group, an amino group, a hydroxyl group and an allyl group. R ⁴ is a divalent organic group having a functional group selected from the group consisting of an alkoxy group, a phenoxy group, an amino group, a hydroxyl group and an allyl group. .)

（式（３）中、ｎは３〜２５の整数であり、Ｒ^６及びＲ^７は同一又は異なって、水素、水酸基、アルキル基、アルコキシ基又はグリシジル基である。） Moreover, it is preferable to use the cyclic phosphazene oligomer represented by Formula (3) from a viewpoint of stability and suppression of void formation.

(In Formula (3), n is an integer of 3 to 25, and R ⁶ and R ⁷ are the same or different and are hydrogen, a hydroxyl group, an alkyl group, an alkoxy group, or a glycidyl group.)

  As the cyclic phosphazene oligomer represented by the above formula (3), for example, FP-100, FP-110 (above, Fushimi Pharmaceutical Co., Ltd.) and the like are commercially available.

  The content of the phosphazene compound includes the epoxy resin (component A), phenol resin (component B), elastomer (component D), curing accelerator (component E) and phosphazene compound (other components) contained in the epoxy resin composition. It is preferable that it is 10 to 30 weight% of the whole organic component containing. That is, when the content of the phosphazene compound is less than 10% by weight of the whole organic component, the flame retardancy of the sealing resin sheet 1 is reduced and the unevenness of the adherend (for example, a substrate on which electronic components are mounted) is followed. Tend to be reduced and voids tend to occur. When the content exceeds 30% by weight of the entire organic component, tackiness is likely to occur on the surface of the sealing resin sheet 1, and workability tends to be lowered, such as difficulty in alignment with the adherend.

  Moreover, the said metal hydroxide and a phosphazene compound can be used together, and the sealing resin sheet 1 excellent in the flame retardance can also be obtained, ensuring the flexibility required for sheet sealing. By using both in combination, sufficient flame retardancy when only the metal hydroxide is used and sufficient flexibility can be obtained when only the phosphazene compound is used.

  Among the above flame retardants, from the viewpoint of the deformability of the thermosetting sealing resin sheet during molding of resin sealing, the ability to follow the unevenness of electronic parts and adherends, and the adhesion to electronic parts and adherends It is desirable to use an organic flame retardant, and a phosphazene flame retardant is particularly preferably used.

  In addition to the above components, the epoxy resin composition can be appropriately mixed with other additives such as a pigment including carbon black as necessary.

(Method for producing thermosetting sealing resin sheet)
A method for producing a thermosetting sealing resin sheet will be described below. First, an epoxy resin composition is prepared by mixing the above-described components. The mixing method is not particularly limited as long as each component is uniformly dispersed and mixed. Thereafter, for example, a varnish in which each component is dissolved or dispersed in an organic solvent or the like is applied to form a sheet. Alternatively, a kneaded material may be prepared by directly kneading each compounding component with a kneader or the like, and the kneaded material thus obtained may be extruded to form a sheet.

  As a specific production procedure using a varnish, the above components A to E and, if necessary, other additives are appropriately mixed according to a conventional method, and uniformly dissolved or dispersed in an organic solvent to prepare a varnish. Subsequently, the sealing resin sheet 1 in a B-stage state can be obtained by applying the varnish on a support such as polyester and drying it. And if necessary, in order to protect the surface of a thermosetting sealing resin sheet, you may bond together peeling sheets, such as a polyester film. The release sheet peels at the time of sealing.

  The organic solvent is not particularly limited, and various conventionally known organic solvents such as methyl ethyl ketone, acetone, cyclohexanone, dioxane, diethyl ketone, toluene, and ethyl acetate can be used. These may be used alone or in combination of two or more. Usually, it is preferable to use an organic solvent so that the solid content concentration of the varnish is in the range of 30 to 60% by weight.

  Although the thickness of the sheet after drying the organic solvent is not particularly limited, it is usually preferably set to 5 to 100 μm, more preferably 20 to 70 μm, from the viewpoint of uniformity of thickness and the amount of residual solvent. is there.

  On the other hand, when kneading is used, the above components A to E and, if necessary, each component of other additives are mixed using a known method such as a mixer, and then kneaded to prepare a kneaded product. . The method of melt kneading is not particularly limited, and examples thereof include a method of melt kneading with a known kneader such as a mixing roll, a pressure kneader, or an extruder.

  The kneading conditions are not particularly limited as long as the temperature is equal to or higher than the softening point of each component described above. For example, when considering the thermosetting property of 30 to 150 ° C. and the epoxy resin, preferably 40 to 140 ° C., more preferably It is 60-120 degreeC, and time is 1 to 30 minutes, for example, Preferably it is 5 to 15 minutes. Thereby, a kneaded material can be prepared.

  By molding the obtained kneaded material by extrusion molding, the B-stage encapsulating resin sheet 1 can be obtained. Specifically, the encapsulating resin sheet 1 can be formed by extrusion molding in a high temperature state without cooling the kneaded material after melt-kneading. Such an extrusion method is not particularly limited, and examples thereof include a T-die extrusion method, a roll rolling method, a roll kneading method, a co-extrusion method, and a calendar molding method. The extrusion temperature is not particularly limited as long as it is equal to or higher than the softening point of each component described above, but considering the thermosetting property and moldability of the epoxy resin, for example, 40 to 150 ° C, preferably 50 to 140 ° C, Preferably it is 70-120 degreeC. By the above, the sealing resin sheet 1 can be formed.

  The thermosetting sealing resin sheet thus obtained may be used by being laminated so as to have a desired thickness if necessary. That is, the thermosetting sealing resin sheet may be used in a single layer structure, or may be used as a laminate formed by laminating two or more multilayer structures.

<Electronic component package manufacturing method>
The manufacturing method of the electronic component package of the present embodiment includes a preparation step of preparing a mounting substrate on which the electronic component is mounted, and the thermosetting sealing resin sheet is laminated on the mounting substrate so as to cover the electronic component. A laminate forming step of forming a laminate having a total thickness of 0.75 mm or less, and a sealing step of thermosetting the thermosetting sealing resin sheet.

  In order to obtain the PonP structure as shown in FIG. 2, the first package that is the lower package and the second package that is the upper package are separately prepared in advance, and the procedure of finally stacking both packages is preferably employed. be able to. The difference in the manufacturing procedure between the first package and the second package is mainly that the resin sealing portion (that is, the semiconductor chip and the sealing resin covering the semiconductor chip) in the first package is small compared to the second package. In the second package, the bumps provided on the back surface of the substrate are larger than the first package, and the other parts are almost the same. Therefore, the manufacturing procedure of the first package will be mainly described with reference to FIG. To do. In this embodiment, a mode in which a semiconductor chip is used as an electronic component will be described.

(Production of the first package)
In the preparation step, a mounting substrate on which a semiconductor chip as an electronic component is mounted is prepared. As shown in FIG. 2, at least one first semiconductor chip 12 is fixed on the substrate 15. The first semiconductor chip 12 is fixed to the substrate 15 via a die bond film 13. Although only one first semiconductor chip 12 is shown in FIG. 2, two, three, four, five or more first semiconductor chips 12 are provided depending on the specification of the target package. It may be fixed to the substrate 15.

(First semiconductor chip)
Various chips can be used as the first semiconductor chip 12 except that the size in plan view is smaller than that of the semiconductor chip 22 mounted on the second package. A kind of logic chip or processor can be preferably used. Although the thickness of the 1st semiconductor chip 12 is not specifically limited, Usually, there are many cases of 100 micrometers or less. In addition, with the recent thinning of semiconductor packages, the first semiconductor chip 12 of 75 μm or less, and further 50 μm or less is being used.

(substrate)
As the substrate 15, a conventionally known substrate such as a printed wiring board can be used. Further, an organic substrate made of glass epoxy, BT (bismaleimide-triazine), polyimide, or the like can be used. However, the present embodiment is not limited to this, and includes a circuit board that can be used by mounting a semiconductor element and electrically connecting the semiconductor element. The thickness of the board | substrate 15 is not specifically limited, It can select suitably from the range of 100-500 micrometers. The substrate 15 may have a single layer structure or a multilayer structure, and a through electrode penetrating in the thickness direction may be formed.

  Electrodes are formed on the upper surface of the first package for electrical connection with the bumps formed on the second package (not shown). Since the space for forming this electrode is provided around the resin sealing portion on the upper surface of the substrate 15, the area in plan view of the semiconductor chip 12 and the sealing resin sheet 11 is smaller than that of the second package.

(Die bond film)
As the die bond film 13, a conventionally known die bond film for fixing a semiconductor chip can be used. The thickness of the die bond film 13 may be about 5 μm to 60 μm.

(Fixing method)
As a method of fixing the first semiconductor chip 12 on the substrate 15, for example, after the die bond film 13 is laminated on the substrate 15, the first semiconductor chip is arranged on the die bond film 13 so that the wire bond surface is on the upper side. The method of laminating 12 is mentioned. Alternatively, the first semiconductor chip 12 with the die bond film 13 attached in advance may be disposed on the substrate 15 and stacked.

  Since the die bond film 13 is in a semi-cured state, the die bond film 13 is thermally cured by performing heat treatment under a predetermined condition after the die bond film 13 is placed on the substrate 15, so that the first semiconductor chip 12 is mounted on the substrate. 15 is fixed. The temperature at which the heat treatment is performed is preferably 100 to 200 ° C, more preferably 120 to 180 ° C. The heat treatment time is preferably 0.25 to 10 hours, more preferably 0.5 to 8 hours.

(Wire bonding process)
The wire bonding step is a step of electrically connecting the tips of terminal portions (for example, inner leads) of the substrate 15 and electrode pads (not shown) on the first semiconductor chip 12 with bonding wires 14 (see FIG. 2). ). As the bonding wire 14, for example, a gold wire, an aluminum wire, or a copper wire is used. The temperature at the time of wire bonding is 80 to 250 ° C, preferably 80 to 220 ° C. The heating time is several seconds to several minutes. The connection is performed by a combination of vibration energy by ultrasonic waves and crimping energy by applying pressure while being heated so as to be within the temperature range.

(Laminate formation process)
In the laminated body forming step, the sealing resin sheet 11 is laminated on the substrate 15 so as to cover the semiconductor chip 12. The sealing resin sheet 11 functions as a sealing resin for protecting the semiconductor chip 12 and its accompanying elements from the external environment.

  The method for laminating the sealing resin sheet 11 is not particularly limited, and a melt-kneaded product of a resin composition for forming the sealing resin sheet is extruded and placed on the substrate 15 and pressed. Thus, a method for forming and laminating the sealing resin sheet 11 at once, or a resin composition for forming the sealing resin sheet 11 is applied onto the release treatment sheet, and the coating film is dried and sealed. A method of transferring the sealing resin sheet 11 onto the substrate 15 after forming the stop resin sheet 11 is exemplified.

  In the present embodiment, by employing the sealing resin sheet 11, the semiconductor chip 12 can be embedded simply by sticking on the substrate 15 to the cover of the semiconductor chip 12, and the production efficiency of the package can be improved. . In this case, the sealing resin sheet 11 can be laminated on the substrate 15 by a known method such as hot pressing or laminator. As the hot press conditions, the temperature is, for example, 40 to 120 ° C., preferably 50 to 100 ° C., the pressure is, for example, 50 to 2500 kPa, preferably 100 to 2000 kPa, and the time is, for example, 0 .3 to 10 minutes, preferably 0.5 to 5 minutes. In consideration of improvement in the adhesion and followability of the sealing resin sheet 11 to the semiconductor chip 12 and the substrate 15, it is preferable to press under reduced pressure conditions (for example, 10 to 2000 Pa).

(Sealing process)
In the sealing step, the sealing resin sheet 11 is thermally cured to perform resin sealing. The conditions of the thermosetting treatment of the thermosetting sealing resin sheet are preferably from 100 ° C. to 200 ° C., more preferably from 120 ° C. to 180 ° C. as the heating temperature, and preferably from 10 minutes to 180 minutes, more preferably from 30 minutes as the heating time. You may pressurize as needed for 120 minutes. In the pressurization, preferably 0.1 MPa to 10 MPa, more preferably 0.5 MPa to 5 MPa can be employed.

(Post-curing process)
In the present embodiment, a post-curing step of after-curing the sealing resin sheet may be performed after the sealing step. In this step, the sealing resin insufficiently cured in the sealing step is completely cured. Although the heating temperature in this process changes with kinds of sealing resin, it exists in the range of 165-185 degreeC, for example, and heating time is about 0.5 to 8 hours. A semiconductor package can be manufactured through a sealing process or a post-curing process.

(Bump formation)
Finally, a plurality of bumps 16 are formed on the surface of the substrate 15 opposite to the surface on which the semiconductor chip 12 is mounted. The bumps 16 can be provided by a known method such as solder balls or solder plating. The material of the bump is not particularly limited. For example, a tin-lead metal material, a tin-silver metal material, a tin-silver-copper metal material, a tin-zinc metal material, a tin-zinc-bismuth metal material, etc. Solders (alloys), gold-based metal materials, copper-based metal materials, and the like.

(Production of second package)
The second semiconductor chip 22 mounted on the second package is not particularly limited, and for example, a memory chip can be used. Further, as shown in FIG. 2, not only one semiconductor chip 22 is mounted, but a plurality of semiconductor chips may be stacked in multiple stages. After the semiconductor chip 22 is fixed to the substrate 25 via the die bond film 23, the semiconductor chip 22 and the substrate 25 are electrically connected by the bonding wire 24. Next, the sealing resin sheet 21 is bonded to the substrate 25 so as to cover the semiconductor chip 22, and the sealing resin sheet 21 is subjected to thermosetting treatment to perform resin sealing. Finally, a plurality of bumps 26 are formed on the back surface of the substrate 25 (the surface opposite to the mounting surface of the semiconductor chip 22). At this time, the height of the bump 26 is made larger than the height of the resin sealing portion on the first package so as to secure a standoff (space between packages). These steps can be performed in the same manner as the first package step.

(Package lamination)
The stacking of the first package and the second package can be performed using a known device such as a package mounter corresponding to the PoP structure. Although the heating temperature of the reflow process in that case is not specifically limited, What is necessary is just about 240-270 degreeC.

[Second Embodiment]
In the first embodiment, the semiconductor chip is fixed to the substrate by a die bond film, and the electrical connection between the two is achieved by wire bonding. However, in the second embodiment, the protruding electrode provided on the semiconductor chip is used. The fixing and electrical connection between the two may be achieved by flip-chip connection. Accordingly, the second embodiment is different from the first embodiment only in the fixing mode in the fixing step, and thus the difference will be mainly described below.

  In the present embodiment, in the fixing step, the first semiconductor chip is fixed to the substrate by flip chip connection (not shown). In the flip-chip connection, so-called face-down mounting is performed in which the circuit surface of the first semiconductor chip faces the substrate. The first semiconductor chip is provided with a plurality of protruding electrodes such as bumps, and the protruding electrodes and electrodes on the substrate are connected. In addition, an underfill material is filled between the substrate and the first semiconductor chip for the purpose of reducing the difference in thermal expansion coefficient between them and protecting the space between them.

  It does not specifically limit as a connection method, It can connect by a conventionally well-known flip chip bonder. For example, the conductive material is melted while pressing the protruding electrodes, such as bumps, formed on the first semiconductor chip in contact with the bonding conductive material (solder or the like) attached to the connection pads of the substrate. It is possible to secure electrical continuity between the first semiconductor chip and the substrate and fix the first semiconductor chip to the substrate (flip chip bonding). Generally, the heating condition at the time of flip chip connection is 240 to 300 ° C., and the pressurizing condition is 0.5 to 490 N.

  The material for forming the bump as the protruding electrode is not particularly limited. For example, a tin-lead metal material, a tin-silver metal material, a tin-silver-copper metal material, a tin-zinc metal material, Examples thereof include solders (alloys) such as a tin-zinc-bismuth metal material, a gold metal material, and a copper metal material.

  As the underfill material, a conventionally known liquid or film-like underfill material can be used.

(Other embodiments)
The aspect of flip chip connection is not limited to the connection by the bump as the protruding electrode described in the second embodiment, but the connection by the conductive adhesive composition or the protrusion combining the bump and the conductive adhesive composition. Connection by structure can also be employed. In the present invention, as long as face-down mounting in which the circuit surface of the first semiconductor chip is connected to face the substrate, it is referred to as flip-chip connection regardless of the connection mode such as the protruding electrode and the protruding structure. To do. As the conductive adhesive composition, a conventionally known conductive paste obtained by mixing a thermosetting resin such as an epoxy resin with a conductive filler such as gold, silver, or copper can be used. When the conductive adhesive composition is used, the first semiconductor chip can be fixed by performing thermosetting treatment at 80 to 150 ° C. for about 0.5 to 10 hours after mounting the first semiconductor chip on the substrate.

  Hereinafter, preferred embodiments of the present invention will be described in detail by way of example. However, the materials, blending amounts, and the like described in the examples are not intended to limit the scope of the present invention only to those examples, but are merely illustrative examples, unless otherwise limited.

[Example 1]
(Preparation of sealing resin sheet)
The following components were blended with a mixer, melt-kneaded at 120 ° C. for 2 minutes with a twin-screw kneader, and then extruded from a T die to prepare a sealing resin sheet A having a thickness of 200 μm.

Epoxy resin: Bisphenol F type epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., YSLV-80XY (epochine equivalent 200 g / eq. Softening point 80 ° C.)) 5.6% by weight
Phenolic resin: phenolic resin having a biphenylaralkyl skeleton (Maywa Kasei Co., Ltd., MEH-7851-SS (hydroxyl equivalent: 203 g / eq., Softening point: 67 ° C.))
5.9% by weight
Curing accelerator: Imidazole catalyst as a curing catalyst (manufactured by Shikoku Chemicals Co., Ltd., 2PHZ-PW) 0.2% by weight
Elastomer (manufactured by Kaneka Corporation, SIBSTAR 072T) 5.0% by weight
Inorganic filler: spherical fused silica powder (manufactured by Denki Kagaku Kogyo Co., Ltd., FB-9454FC, average particle size 19 μm) 79.9% by weight
Silane coupling agent: Epoxy group-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403) 0.1% by weight
Organic flame retardant (FP-100, manufactured by Fushimi Pharmaceutical Co., Ltd.) 3.0% by weight
Carbon black (Mitsubishi Chemical Corporation, # 20) 0.3 wt%

[Example 2]
(Preparation of sealing resin sheet)
The following components were blended with a mixer, melt-kneaded at 120 ° C. for 2 minutes with a twin-screw kneader, and then extruded from a T-die to prepare a sealing resin sheet B having a thickness of 200 μm.

Epoxy resin: Bisphenol F type epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., YSLV-80XY (epochine equivalent 200 g / eq. Softening point 80 ° C.)) 7.0% by weight
Phenolic resin: phenolic resin having a biphenylaralkyl skeleton (Maywa Kasei Co., Ltd., MEH-7851-SS (hydroxyl equivalent: 203 g / eq., Softening point: 67 ° C.))
7.4% by weight
Curing accelerator: Imidazole catalyst as a curing catalyst (manufactured by Shikoku Chemicals Co., Ltd., 2PHZ-PW) 0.2% by weight
Elastomer (manufactured by Kaneka Corporation, SIBSTAR 072T) 6.3% by weight
Inorganic filler: spherical fused silica powder (manufactured by Denki Kagaku Kogyo Co., Ltd., FB-9454FC, average particle diameter 19 μm) 74.9% by weight
Silane coupling agent: Epoxy group-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403) 0.1% by weight
Organic flame retardant (FP-100, manufactured by Fushimi Pharmaceutical Co., Ltd.) 3.7% by weight
Carbon black (Mitsubishi Chemical Corporation, # 20) 0.3 wt%

[Example 3]
(Preparation of sealing resin sheet)
The following components were blended with a mixer, melt-kneaded at 120 ° C. for 2 minutes with a twin-screw kneader, and then extruded from a T die to prepare a sealing resin sheet C having a thickness of 200 μm.

Epoxy resin: Bisphenol F type epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., YSLV-80XY (epochine equivalent 200 g / eq. Softening point 80 ° C.)) 8.4% by weight
Phenolic resin: phenolic resin having a biphenylaralkyl skeleton (Maywa Kasei Co., Ltd., MEH-7851-SS (hydroxyl equivalent: 203 g / eq., Softening point: 67 ° C.))
8.9% by weight
Curing accelerator: Imidazole catalyst as a curing catalyst (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PHZ-PW) 0.3% by weight
Elastomer (manufactured by Kaneka Corporation, SIBSTAR 072T) 7.6% by weight
Inorganic filler: spherical fused silica powder (manufactured by Denki Kagaku Kogyo Co., Ltd., FB-9454FC, average particle diameter 19 μm) 69.9% by weight
Silane coupling agent: Epoxy group-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403) 0.1% by weight
Organic flame retardant (FP-100, manufactured by Fushimi Pharmaceutical Co., Ltd.) 4.5% by weight
Carbon black (Mitsubishi Chemical Corporation, # 20) 0.3 wt%

[Comparative Example 1]
(Preparation of sealing resin sheet)
The following components were blended with a mixer, melt-kneaded at 120 ° C. for 2 minutes with a twin-screw kneader, and then extruded from a T die to prepare a sealing resin sheet D having a thickness of 200 μm.

Epoxy resin: bisphenol F type epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., YSLV-80XY (epochine equivalent 200 g / eq. Softening point 80 ° C.)) 3.3 wt%
Phenolic resin: phenolic resin having a biphenylaralkyl skeleton (Maywa Kasei Co., Ltd., MEH-7851-SS (hydroxyl equivalent: 203 g / eq., Softening point: 67 ° C.))
3.5% by weight
Curing accelerator: Imidazole catalyst as a curing catalyst (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PHZ-PW) 0.1% by weight
Elastomer (manufactured by Kaneka Corporation, SIBSTAR 072T) 3.0% by weight
Inorganic filler: spherical fused silica powder (manufactured by Denki Kagaku Kogyo Co., Ltd., FB-9454FC, average particle size 19 μm) 87.9% by weight
Silane coupling agent: Epoxy group-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403) 0.1% by weight
Organic flame retardant (FP-100, manufactured by Fushimi Pharmaceutical Co., Ltd.) 1.8% by weight
Carbon black (Mitsubishi Chemical Corporation, # 20) 0.3 wt%

[Comparative Example 2]
(Preparation of sealing resin sheet)
The following components were blended with a mixer, melt-kneaded at 120 ° C. for 2 minutes with a twin-screw kneader, and then extruded from a T die to prepare a sealing resin sheet E having a thickness of 200 μm.

Epoxy resin: Bisphenol F type epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., YSLV-80XY (epochine equivalent 200 g / eq. Softening point 80 ° C.)) 11.3% by weight
Phenolic resin: phenolic resin having a biphenylaralkyl skeleton (Maywa Kasei Co., Ltd., MEH-7851-SS (hydroxyl equivalent: 203 g / eq., Softening point: 67 ° C.))
11.9% by weight
Curing accelerator: Imidazole catalyst as a curing catalyst (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PHZ-PW) 0.4% by weight
Elastomer (manufactured by Kaneka Corporation, SIBSTAR 072T) 10.1% by weight
Inorganic filler: Spherical fused silica powder (manufactured by Denki Kagaku Kogyo Co., Ltd., FB-9454FC, average particle size 19 μm) 59.9% by weight
Silane coupling agent: Epoxy group-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403) 0.1% by weight
Organic flame retardant (FP-100, manufactured by Fushimi Pharmaceutical Co., Ltd.) 6.0% by weight
Carbon black (Mitsubishi Chemical Corporation, # 20) 0.3 wt%

(Measurement of linear expansion coefficient and glass transition temperature (Tg) of encapsulating resin sheet)
The linear expansion coefficient was measured using a thermomechanical analyzer (manufactured by Rigaku Corporation: model: TMA8310). Specifically, each sealing resin sheet was heated and cured at 150 ° C. for 1 hour, and after obtaining a measurement sample from this cured product with a sample size of 25 mm long × 4.9 mm wide × 200 μm thick, The measurement sample was set in a film tensile measurement jig and measured under conditions of a tensile load of 4.9 mN and a temperature increase rate of 10 ° C./min to obtain a linear expansion coefficient. A similar measurement sample is set in a film tensile measurement jig, and the tensile storage elastic modulus and loss elastic modulus in the temperature range of −50 to 300 ° C. are set under the conditions of a frequency of 1 Hz and a heating rate of 10 ° C./min. The glass transition temperature (Tg) was obtained by calculating the value of tan δ (G ″ (loss elastic modulus) / G ′ (storage elastic modulus)) in the measurement.

(Measurement of surface warpage)
As a sample for measuring the amount of surface warpage, as shown in FIG. 3, the silicon chip 2 is mounted on the substrate 5 through the die bond film 3, and the entire surface of the substrate 5 is resin-sealed with the sealing resin sheet 1. The semiconductor package 10 is used.

(Production of semiconductor package for measuring surface warpage)
A die bond film was bonded to a semiconductor chip having the following specifications under the following lamination conditions.

<Semiconductor chip>
Semiconductor chip size: 35 mm □ (thickness 200 μm (= 0.2 mm))

<Die bond film>
Film size: 35mm □ (thickness 25μm)
Manufacturer: Mitsubishi Plastics, Inc. Product name: EM-710

<Lamination conditions>
Lamination temperature: 120 ° C
Laminating speed: 1000rpm
Construction number: 1 time

  Separately, a dry TF-BGA (Thin Fine-Pitch Ball Grid Array) substrate having the following specifications was prepared.

<TF-BGA substrate>
Manufacturer: Nippon Circuit Industry Product name: TFBGA032T (AUS5)
Substrate size: 50 mm □ (thickness 320 μm (= 0.32 mm))
Substrate material: BT Resin, Cu, Ni, Au, solder mask Number of pads: 225
Pad pitch: 1000 μm
Drying conditions: 150 ° C. × 3 hours, then cooled to room temperature in the presence of silica gel

  Next, after bonding the semiconductor chip to a dry TF-BGA substrate under the following lamination conditions, the die bond film was cured by the following heat treatment to mount the semiconductor chip on the substrate.

<Lamination conditions>
Lamination temperature: 120 ° C
Laminating speed: 1000rpm
Construction number: 2 times

<Thermosetting conditions>
Thermosetting conditions: 150 ° C x 1 hour

  Next, the surface of the obtained semiconductor chip mounting substrate was subjected to plasma treatment under the following conditions to perform surface modification.

<Plasma treatment>
Operating gas: Argon Gas flow rate: 40cc / min
Output: 100W
Irradiation time: 1 minute

  On the semiconductor chip mounting substrate after the plasma treatment, each of the sealing resin sheets A to E was pasted by a vacuum press under the pasting conditions shown below. At this time, the total thickness of the substrate, the die bond film, and the sealing resin sheet (with the semiconductor chip included) was 750 μm.

<Paste conditions>
Temperature: 90 ° C
Applied pressure: 1.5 MPa
Degree of vacuum: 25 Torr (3333 Pa)
Press time: 1 minute

  After opening to atmospheric pressure, after the sealing resin sheet is thermally cured in a hot air dryer at 150 ° C. for 1 hour, it is allowed to stand at 25 ° C. for 1 hour to measure the amount of surface warp after heat treatment 1. A semiconductor package was prepared.

  Furthermore, the semiconductor package for measuring the amount of surface warpage during the heat treatment 2 was manufactured by putting the semiconductor package that had undergone the heat treatment 1 into an atmosphere of 240 ° C.

(Measurement procedure of surface warpage of encapsulating resin sheet)
Using the semiconductor package after the heat treatment 1 and the semiconductor package after the heat treatment 2 as a sample for measuring the amount of surface warpage, sealing is performed using a temperature variable laser three-dimensional measuring instrument (manufactured by T-Tech Co., Ltd.). Measure the height of the center of the surface of the resin sheet (intersection of diagonal lines in plan view shown in FIG. 4A) and the height of the four corners of the surface, and calculate the difference between the height of the center of the surface of the sealing resin sheet and the four corners of the surface. The amount was W (see FIGS. 4B and 4C). Specifically, as shown in FIGS. 4A to 4C, the surface shape along each diagonal line is obtained by scanning the surface twice along two diagonal lines of the encapsulating resin sheet, and a total of four surfaces. The surface warp amount W was calculated by calculating the difference between the average height of the four corners and the height of the central portion. The case where the surface warpage amount of the semiconductor package was within an allowable range (−0.6 mm to 0.1 mm) was evaluated as “◯”, and the case where the warpage was outside the allowable range was evaluated as “x”. Note that the upper lid of the heating chamber used for the heat treatment 2 was made of glass, and the amount of surface warpage in a 240 ° C. atmosphere was measured by laser. The results are shown in Table 1.

  As can be seen from Table 1, in the semiconductor package produced by the sealing resin sheets of Examples 1 to 3, both the surface warpage amount during the resin sealing and the heat treatment corresponding to the solder reflow are small, and the warping of the sealing resin sheet is Since it is suppressed, it is considered that good reliability can be obtained in the semiconductor package manufactured by these. On the other hand, in Comparative Example 1, the amount of surface warpage during resin sealing is large, and in Comparative Example 2, the warpage during heat treatment corresponding to solder reflow is large. It is considered that the reliability of the entire package obtained is inferior due to the influence of the above.

1, 11, 21 Thermosetting sealing resin sheet 2 Silicon chip 3, 13, 23 Die bond film 5, 15, 25 Substrate 6, 16, 26 Bump 10, 100 Semiconductor package 12 First semiconductor chip 14, 24 Bonding wire 22 2nd semiconductor chip 21 1st thermosetting sealing resin sheet 22 Thermosetting sealing resin sheet T Total thickness W Surface curvature amount

Claims (6)

Containing an inorganic filler in a content of 70 wt% to 80 wt%,
A thermosetting encapsulating resin sheet in which the amount of surface warpage in the following heat treatment 1 and heat treatment 2 is −0.6 mm or more and 0.1 mm or less, respectively.
Heat treatment 1: The thermosetting encapsulating resin sheet is placed on a 50 mm square 0.32 mm thick printed circuit board on which a 35 mm square and 0.2 mm thick silicon chip is mounted via a 25 μm thick die bond film. Bonding is performed so that the total thickness after bonding is 0.75 mm, heat treatment is performed at 150 ° C. for 1 hour to form a sealed body, and then the film is allowed to stand at 25 ° C. for 1 hour.
Heat treatment 2: The sealed body that has undergone the heat treatment 1 is put into a 240 ° C. atmosphere.   The thermosetting encapsulating resin sheet according to claim 1, wherein the linear expansion coefficient after heat treatment at 150 ° C for 1 hour is 15 ppm / K or more and 30 ppm / K or less at the glass transition temperature or less.   The thermosetting sealing resin sheet according to claim 1 or 2, wherein the inorganic filler is silica particles.   The thermosetting sealing resin sheet according to any one of claims 1 to 3, wherein an average particle size of the inorganic filler is 0.1 µm or more and 35 µm or less. A preparation process for preparing a mounting board on which electronic components are mounted;
A laminate in which the thermosetting sealing resin sheet according to any one of claims 1 to 4 is laminated on the mounting substrate so as to cover the electronic component to form a laminate having a total thickness of 0.75 mm or less. An electronic component package manufacturing method comprising: a body forming step, and a sealing step of thermosetting the thermosetting sealing resin sheet. 6. The method of manufacturing an electronic component package according to claim 5, wherein the sealing step is performed after a plurality of laminated bodies obtained by repeating the preparation step and the laminated body forming step are laminated in multiple stages.

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