JP2008251836A - Semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide one liquid type epoxy resin composition which can improve connection reliability and repair property at the time of shock with sufficient balance by using a bonding method and compound having a latent active group while balance of hardenability and storing stability is maintained even if a bonding area is suppressed at the time of using it as an underfill material sealing a part between a semiconductor device and a substrate. <P>SOLUTION: An area with which adhesive is filled is controlled and a cavity part is installed. Latent compound or polymer which generates carboxylic acid or sulfonic acid at the time of heating is contained in the device. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a semiconductor device.

In recent years, miniaturization of LSI devices has been demanded as small electronic devices such as digital cameras, integrated VTRs, cellular phones, and portable terminals have become widespread. For this reason, new packages such as CSP and BGA are used for the purpose of downsizing and improving the characteristics of bare chips while protecting the features of conventional chip mounting packages that can protect semiconductor bare chips such as LSIs and facilitate testing. Is spreading.

This lead-free chip carrier has a large number of input / output connections between the chip and the corresponding substrate in a relatively small package. A lead-free chip carrier typically consists of a package containing a single ceramic, such as alumina, which forms a chip carrier or base on which the chip is mounted. The package on which the chip is mounted is mounted on a larger printed circuit board (PCB) or the like. Specifically, a contact pad that has a mirror image relationship with the contact pad of the package is formed on the PCB, and after both are aligned, they are electrically and mechanically connected by reflow soldering, etc. Is done. When the package is connected to the PCB by solder, solder paste is usually used or solder bumps are used. Generally, an epoxy-based sealing resin (underfill material) is injected into a gap generated by a solder bump between the package and the PCB.

As one method for reducing the area required when mounting a chip on a package or PCB, there is a flip chip connection method. This is a method in which the connection pad on the upper surface side of the chip is directed to the lower surface side and connected to the opposing package or PCB by solder bumps. Also in this case, a gap due to solder bumps is generated between the chip element surface and the chip carrier, or between the chip element surface and the PCB, so that an underfill material is similarly injected. The underfill material not only fills the gaps and spaces in the connection part, but also seals the electrical contacts to protect them from the surroundings, and has a function of bonding the package and the PCB, for example, at a small mechanical joint. It also has the purpose of preventing an excessive force from acting on a certain solder bump joint.

As a method for filling the underfill material, a capillary flow is applied along the outer periphery of the chip or package, and a capillary flow is used to fill the underfill material. There are two types of compression flow for loading chips or packages.

  Since a thermosetting resin is used for such an underfill material, conventionally, after mounting a CSP or BGA on a wiring board, an LSI failure on the CSP or BGA, a connection failure between the CSP or BGA and the wiring board, etc. Was discovered, it was difficult to peel off these thermosetting resins and replace CSP and BGA, and there was a problem of poor repairability.

As a means of improving the repairability of such a semiconductor device, a fixed connection between the bare chip and the substrate is performed using a resin that cures at a predetermined temperature, and when a malfunction occurs in the semiconductor device, the temperature is higher than the predetermined temperature. There is a method of removing the bare chip by softening (see, for example, Patent Document 1). However, a specific underfill material itself that satisfies both reliability and repair characteristics has not been known yet.
Moreover, in order to peel the underfill material as described above from the substrate, there is a method of peeling after being immersed in an organic solvent or the like, but if the peelability (repairability) is improved, the original adhesion performance of the underfill material As the underfill material has improved adhesiveness and durability, the releasability of the underfill material is reduced, and there has not yet been obtained a material that satisfies both the original adhesive performance as an underfill material and the releasability. . Furthermore, there is a method of blending a plasticizer such as acrylic acid esters, aromatic or aliphatic esters with a one-pack type or two-pack type underfill material (see, for example, Patent Document 2). This method can connect a semiconductor device such as CSP or BGA to a wiring board by short-time thermosetting, has excellent heat shock resistance, and can easily remove CSP or BGA when a defect is found. It is said that there are problems such as durability, heat resistance and heat cycle resistance are reduced due to the inclusion of the above plasticizer, and the surroundings are contaminated by bleeding of the plasticizer component from the cured product. was there.

With the recent increase in performance of semiconductor chips, the chip size has also increased, making it difficult to achieve both releasability while maintaining adhesion to the substrate, increasing the area of the residue after peeling, and increasing the removal time. Is a factor that reduces productivity.

Japanese Patent Laid-Open No. 06-69280 JP-A-10-204259

  An object of the present invention is to reliably connect a semiconductor device such as CSP or BGA on a wiring board, and is excellent in heat shock resistance after curing. It is an object of the present invention to provide a semiconductor device that can be easily detached from a wiring board and is excellent in repairability that allows a normal wiring board or a semiconductor device to be reused.

Such an object is achieved by the following present inventions [1] to [4].
[1] A semiconductor device having a structure in which a reinforcing adhesive is filled between a semiconductor element having a solder bump for electrical connection with a substrate, the reinforcing adhesive having an area that can be filled 5 to 95% is filled, and the structure has at least one unfilled space from the center to the outer periphery of the semiconductor element, and the reinforcing adhesive generates carboxylic acid and sulfonic acid by heating. A semiconductor device characterized by being a latent compound and / or a resin.
[2] The semiconductor device according to item [1], wherein the reinforcing adhesive is a thermosetting resin composition.
[3] The semiconductor according to item [2], wherein the thermosetting resin composition is at least one resin composition selected from the group consisting of an epoxy resin composition, a cyanate resin composition, and a maleimide resin composition. apparatus.
[4] The semiconductor device according to item [3], wherein the reinforcing adhesive is a thermosetting resin composition having flux activity.

The present invention relates to a semiconductor device and a method for manufacturing the semiconductor device in which a reinforcing adhesive for solder joints with a wafer having solder bumps for electrical joining to a substrate is used in a structure having a space.
INDUSTRIAL APPLICABILITY The semiconductor device and the semiconductor device manufacturing method of the present invention are excellent in reliability such as heat cycle resistance and the like, and are excellent in repairability.

The semiconductor device and the method for manufacturing the semiconductor device of the present invention will be described below.
First, the semiconductor device of the present invention will be described.
The reinforcing adhesive for the solder joint portion with the semiconductor element having the solder bump for electrical joining with the substrate has a structure having a space. In particular, by adhering 5 to 95% of the area that can be filled with the reinforcing adhesive under the semiconductor element and having a structure having at least one unfilled space from the center to the outer periphery, This makes it possible to facilitate the repair workability. Further, by providing a space with the outside, it can be used as a passage for the generated gas that can be generated from the adhesive or the substrate. If it is less than 5%, the bonding area is insufficient and the connection reliability is lowered. On the other hand, when more than 95% is filled, the repairability is lowered.

  The reinforcing adhesive used here needs to be a latent compound and / or resin that generates carboxylic acid and sulfonic acid by heating. Such a reinforcing adhesive is a thermosetting resin composition containing a compound having a protecting group by reacting a carboxylic acid compound and a vinyl ether compound and / or a resin, or alternatively a cyclohexyl aromatic sulfonate. Specifically, an epoxy resin composition, a cyanate resin composition or a maleimide resin composition can be used, but in common with all materials, a compound that generates carboxylic acid and sulfonic acid by heating and It becomes possible to give flux activity by containing resin.

  The epoxy resin in the epoxy resin composition used for the reinforcing adhesive is not particularly limited because it has two or more glycidyl groups in the molecule, but bisphenol type epoxy resins (bisphenol A type, bisphenol F type, In addition to bisphenol AD type, alicyclic epoxy resin, novolac type epoxy resin, etc., polyglycidyl ether obtained by reacting catechol, resorcinol, or polyhydric alcohols such as glycerin and polyethylene glycol with epichlorohydrin can also be used. Also, obtained by reacting epichlorohydrin with glycidyl ether ester obtained by reacting hydroxycarboxylic acids such as P-hydroxybenzoic acid and β-hydroxynaphthoic acid with epichlorohydrin, or polycarboxylic acids such as phthalic acid and terephthalic acid. Polyglycidyl ester, epoxidized phenol novolak resin, epoxidized cresol novolak resin, mono-epoxy resin, etc. can be used as a reactive diluent for reducing viscosity, and these can be used alone or in combination. Also good.

The form of the epoxy resin is not particularly limited, and it may be liquid or solid, but normally, a resin that becomes liquid when mixed with an acid anhydride curing agent described later is preferably used. Among these, bisphenol A type and bisphenol F type epoxy resins having relatively low molecular weight are preferable. Thereby, the workability | operativity at the time of a composition manufacture and the characteristic after hardening can be made favorable, and material cost can be held down.

  Further, as the curing agent for the epoxy resin, an acid anhydride or a phenol resin is used, but the acid anhydride is not particularly limited, but phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride. Acid, maleic anhydride, succinic anhydride, dodecynyl succinic anhydride, dichlorosuccinic anhydride, methyl nadic acid anhydride, pyromellitic anhydride, methylhexahydrophthalic anhydride, methylcyclohexenedicarboxylic anhydride, endomethylenetetrahydrophthalic anhydride, methyl Endomethylenetetrahydrophthalic anhydride, methylbutenyltetrahydrophthalic anhydride, alkylstyrene-maleic anhydride copolymer, tetrabromophthalic anhydride, polyazeline acid anhydride, chlorendic acid anhydride, benzopheno anhydride Tetracarboxylic acid and the like. Among these, in view of handling workability during production, characteristics after curing, material cost, and industrial supply stability, those which are liquid at normal temperature are preferred. Methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride Acid is particularly preferred. In addition, the storage stability of trimellitic anhydride having a carboxylic acid group may decrease.

The phenol resin may be liquid or solid, and in the case of solid, the softening point is preferably 150 ° C. or less. If the softening point of the phenol novolac resin exceeds the upper limit, the fluidity of the resin at the time of soldering may be reduced, and the effect of improving the solder connection reliability may be reduced. Examples of the phenol compound constituting the phenol novolac resin include phenol, cresol, bisphenol, naphthol, and the like.

Moreover, it is although it does not specifically limit as a compounding quantity of an acid anhydride and a phenol resin, It is preferable to mix | blend 0.4-1.2 equivalent with respect to 1 equivalent of epoxy resins. More preferably, it is 0.5 equivalent-1.1 equivalent. Thereby, the hardened | cured material which has low viscosity and appropriate mechanical strength can be obtained. If the blending amount is less than the lower limit, the mechanical strength may not be sufficient. Moreover, when the said upper limit is exceeded, the viscosity of a composition will come to fall, an uncured part will be easy to be produced, and mechanical strength may fall.

When the reinforcing adhesive used in the semiconductor device of the present invention is an epoxy resin composition, the acid anhydride or phenol resin can be used as a curing agent, and a curing accelerator can be used in combination. Although it does not specifically limit as a hardening accelerator, The adduct type compound marketed as a latent hardening agent can be used. For example, “Amicure PN-23” manufactured by Ajinomoto Fine Techno Co., Ltd., “Amicure MY-24” manufactured by Ajinomoto Co., Ltd., or “Fujicure FX-1000” manufactured by Fuji Kasei Kogyo Co., Ltd. may be used. Also, a general imidazole compound, a master batch type curing agent for a one-component epoxy resin disclosed in JP-A-1-70523, a latent curing agent disclosed in JP-A-6-73156, etc. May be used.

When the reinforcing adhesive used in the semiconductor device of the present invention is a cyanate resin composition, examples of the cyanate resin include bisphenol types such as bisphenol A type cyanate resin, bisphenol E type cyanate resin, and tetramethylbisphenol F type cyanate resin. Examples include cyanate resins and novolac type cyanate resins. The cyanate resin is obtained, for example, by reacting a cyanogen halide compound with phenols.

A metal complex such as cobalt acetylacetonate is used as a reaction catalyst for the cyanate resin, but the reaction can be accelerated by adding an acid anhydride or a phenol resin, and can also have a flux activity. Since these acid anhydrides and phenol resins can also be used as curing agents for epoxy resins, they may be used by mixing an epoxy resin with a cyanate resin composition.

When the reinforcing adhesive used in the semiconductor device of the present invention is a maleimide resin composition, the maleimide resin has two or more maleimide groups in the molecule and is not particularly limited, but N, N'-m- Phenylene bismaleimide, N, N'-p-phenylene bismaleimide, N-N'-m-toluylene bismaleimide, N, N'-4,4'biphenylene bismaleimide, N, N '-(3,3' -Dimethyl-biphenylene) bismaleimide, N, N'-4,4'-diphenylmethane bismaleimide, N, N'-4,4 '-(3,3'-dimethyldiphenylmethane) bismaleimide, N, N'-4 , 4 ′-(3,3′-diethyldiphenylmethane) bismaleimide, N, N′-4,4′-diphenylpropane bismaleimide, N, N′-4,4′-diphenyl ether bismaleimide N, N'-4,4'-diphenylsulfone bismaleimide, phenylaralkylmaleimide resin, etc., and these can be used alone or in combination of two or more.

As a curing agent for maleimide resin materials, it can be reacted with maleimide double bonds using peroxides, or added with amine compounds, but it acts as a curing agent and has flux activity. And an aryl group-containing phenol compound is preferred. For example, 3- (2-hydroxyphenyl) propene, 3- (4-hydroxyphenyl) propene, 3- (2-hydroxy-4-methylphenyl) propene and the like can be mentioned.

In the reinforcing adhesive used in the semiconductor device of the present invention, as a latent compound that generates carboxylic acid having flux activity by heating, for example, a compound having a protective group by reacting a carboxylic acid compound and a vinyl ether compound, an oligomer or Polymers or cyclohexyl aromatic sulfonates can be used.
Examples of the compound having a protecting group obtained by reacting a carboxylic acid compound and a vinyl ether compound include carboxylic acid compounds such as benzoic acid, terephthalic acid, and trimesic acid and, for example, isobutyl vinyl ether, vinyl ethyl ether, 2,3-dihydrofuran, A compound obtained by reacting a vinyl ether compound such as 3,4-dihydro-2H-pyran with a non-catalyst or a small amount of an organic acid in a solvent-free or ketone-based solvent is used. Or what was made to react with the acrylic acid oligomer and polymer which have a carboxyl group can also be used. Examples of the cyclohexyl aromatic sulfonate include cyclohexyl = 4-methylbenzenesulfonate, 2-methylcyclohexyl = 4-methylbenzenesulfonate, 3-methylcyclohexyl = 4-methylbenzenesulfonate, 4-methylcyclohexyl = 4-methylbenzene. Sulfonate, 4-butylcyclohexyl 4-methylbenzene sulfonate, 4-cyclohexyl cyclohexyl 4-methylbenzene sulfonate, 2,6-dimethylcyclohexyl 4-methylbenzene sulfonate, 2,4-dimethylcyclohexyl 4-methylbenzene sulfonate, 3,4-dimethylcyclohexyl = 4-methylbenzenesulfonate, 3,5-dimethylcyclohexyl = 4-methylbenzenesulfonate, 2-isopropyl -5-methylcyclohexyl = 4-methylbenzenesulfonate, 2-hydroxycyclohexyl = 4-methylbenzenesulfonate, 4-hydroxycyclohexyl = 4-methylbenzenesulfonate and 4,4′-bicyclohexylbis (4-methylbenzenesulfonate) P-toluenesulfonic acid cyclohexyl such as cyclohexyl, 4-biphenyl sulfonate biphenyl sulfonic acid cyclohexyl, cyclohexyl = 1-naphthalene sulfonate and cyclohexyl 2-naphthalene sulfonate naphthalene sulfonic acid cyclohexyl, etc. Among these, p-toluenesulfonic acid cyclohexyl cyclohexyls are more preferable, and among them, cyclohexyl = 4-methyl. Benzenesulfonate, 3-methylcyclohexyl = 4-methylbenzenesulfonate, 3,5-dimethylcyclohexyl = 4-methylbenzenesulfonate, 4-butylcyclohexyl = 4-methylbenzenesulfonate, 2-isopropyl-5-methylcyclohexyl = 4-methyl Benzenesulfonate, 2-hydroxycyclohexyl = 4-methylbenzenesulfonate and 4-hydroxycyclohexyl = 4-methylbenzenesulfonate are preferred.

The reinforcing adhesive used in the semiconductor device of the present invention can contain a rubber component for imparting flexibility and a thermoplastic resin such as a xylene resin. Thereby, it is excellent in adhesiveness with a to-be-adhered body, and heat cycle resistance is also improved.

In the reinforcing adhesive used in the semiconductor device of the present invention, the amount of the thermoplastic resin is not particularly limited, but an epoxy resin composition, a cyanate resin composition, or a reinforcing adhesive used in the semiconductor device, or It is preferable that it is 5-40 weight part with respect to 100 weight part of maleimide resin-type resin compositions. More preferably, it is 10-30 weight part. Thereby, a favorable adhesive force can be imparted to the composition without substantially affecting other properties. When the blending amount of the thermoplastic resin is less than the lower limit, the blending effect of the thermoplastic resin may not be sufficient. On the other hand, if the upper limit is exceeded, the plasticizing effect increases, the adhesiveness at room temperature decreases, and the connection reliability, which is the original purpose, tends to decrease.

The reinforcing adhesive used in the semiconductor device of the present invention is not particularly limited, but an inorganic filler can be blended. Thereby, improvement of the heat resistance of a composition, reduction of a thermal expansion coefficient, etc. can be aimed at. The inorganic filler is not particularly limited, and examples thereof include calcium carbonate, aluminum hydroxide, silica, clay, talc, alumina, and glass powder. Among these, crystalline silica and fused silica are preferable. Thereby, in addition to the said effect, the electrical property of a composition can be improved and a viscosity rise can be suppressed low.

Although it does not specifically limit as a compounding quantity in the case of using the said inorganic filler, With respect to 100 weight part of epoxy resin composition, cyanate-type resin composition, or maleimide-type resin composition of the reinforcing adhesive used for a semiconductor device 0 to 200 parts by weight, more preferably 0 to 150 parts by weight from the viewpoint of workability. Although it is not necessary to use an inorganic filler, if it is used, the linear expansion coefficient of the composition can be reduced, and as a result, the heat cycle resistance can be further improved. However, when the upper limit is exceeded, the viscosity becomes very high and workability is lowered, and the physical properties of the cured product, such as adhesive strength and bending strength, may be significantly lowered.

The reinforcing adhesive used in the semiconductor device of the present invention includes dyes, modifiers, and thixotropic agents as necessary, in addition to the above-described formulations, as long as they do not contradict the purpose of the present invention. Additives such as coloring inhibitors, anti-aging agents, mold release agents, leveling agents, reactive or non-reactive diluents can be blended.

For the method for producing the reinforcing adhesive used in the semiconductor device of the present invention, the same general stirring and mixing apparatus and processing conditions as those for the ordinary method for producing an epoxy resin composition are applied. Equipment used includes a mixing roll, a dissolver, a planetary mixer, a kneader, and an extruder. As processing conditions, epoxy, cyanate, or maleimide resin, which is the main agent, may be heated to dissolve and / or lower the viscosity and improve the stirring and mixing efficiency. Further, cooling may be performed in order to remove frictional heat generation, reaction heat generation, and the like. The time for stirring and mixing may be determined if necessary, and is not particularly limited.

  As a method for assembling a semiconductor element using the reinforcing adhesive used in the semiconductor device of the invention, in the case of capillary flow, it is applied to the outer peripheral portion of the chip or package and filled by utilizing the capillary phenomenon. Then, it joins by heat curing with a hot air dryer, a hot air drying furnace, a far-infrared curing furnace, etc. In the case of a compression flow, bumps are first formed on a number of semiconductor elements on which electrical circuits are formed on a wafer, and then an adhesive is applied to the substrate surface. As a method for applying the adhesive, screen printing, transfer, dispensing, or the like can be used. Next, a method of bonding the applied element to the substrate is performed by a hot air dryer, a hot air dryer, a far-infrared curing furnace, a pulse heat, a reflow method, or the like. The surface of the adhesive having flux activity is activated by expressing the flux activity by the contained curing agent, and is bonded to the metal terminal of the substrate. At the same time, the adhesive is melted and then cured by a curing reaction to be sealed. When the curing is insufficient, post-baking can be performed after joining.

  Hereinafter, the present invention will be described in detail by way of examples.

Production of reinforcing adhesive for use in semiconductor devices (Example 1)
100 parts by weight of epoxy resin (“Epicoat 828” (bisphenol A type epoxy resin, epoxy equivalent: about 189) manufactured by Japan Epoxy Resin Co., Ltd.), acid anhydride (“MT-500” manufactured by Shin Nippon Rika Co., Ltd. (methyltetrahydroanhydride) as a curing agent Phthalic acid, acid anhydride equivalent 169) 80 parts by weight, adduct-based compound (“MY-24” manufactured by Ajinomoto Fine Techno Co.) as a curing accelerator, 3 parts by weight, fused silica (manufactured by Denki Kagaku Kogyo Co., Ltd. “ FB-35 "(average particle size 11 μm)) 100 parts by weight, pigment 1 part by weight (Mitsubishi Chemical" MA-600 "(carbon black)), benzoic acid (Kanto Chemicals reagent grade 1) and 3, 4 -Dihydro-2H-pyran (Kanto Chemical Co., Inc.) pre-reacted and protected with 5 parts by weight of compound, and then uniformly dispersed at room temperature using a planetary mixer Was sufficiently mixed with stirring to obtain a reinforcing adhesive 1. A circuit board on which a 20 × 20 mm BGA (1.5 mm pitch, 169 pins, solder ball diameter 0.8 mm) was mounted was shown in FIG. As shown in the figure, the composition was injected into the four corners of the BGA, and the composition was filled by capillary flow using a dispenser between the BGA and the circuit board. A substrate was prepared.

(Example 2)
The compound obtained by reacting benzoic acid of Example 1 (reagent grade 1 manufactured by Kanto Chemical Co., Inc.) with 3,4-dihydro-2H-pyran (manufactured by Kanto Chemical Co., Inc.) in advance and protecting it with 5 parts by weight of cyclohexyl 4-methylbenzenesulfonate Except for the replacement, a reinforcing adhesive 2 was obtained in the same manner as in Example 1. In the same manner as described above, an evaluation substrate having a bonding area of about 40% was prepared by using a dispenser.

Example 3
The amount of the benzoic acid of Example 1 (reagent grade 1 manufactured by Kanto Chemical Co., Inc.) and 3,4-dihydro-2H-pyran (manufactured by Kanto Chemical Co., Ltd.) previously reacted and protected was increased to 10 parts by weight. A reinforcing adhesive 3 was obtained in the same manner as in Example 1 except that the amount was increased to 200 parts by weight. As a connection method by compression flow, bumps are vertically connected using a chip with bumps (20 mm × 20 mm, Sn37Pb solder bumps or Sn3.5Ag solder bumps) and a FR4 substrate (with pads) having a thickness of 0.75 mm as a pair. Sealing was performed by applying a liquid sealing material to the gap generated there, for example, as shown in FIG. At this time, an evaluation substrate having an adhesion area of about 60% was prepared.

Example 4
Benzoic acid of Example 3 (reagent grade 1 manufactured by Kanto Chemical Co., Inc.) and 3,4-dihydro-2H-pyran (manufactured by Kanto Chemical Co., Ltd.) were reacted in advance with 10 parts by weight of cyclohexyl 4-methylbenzenesulfonate. Except for the replacement, a reinforcing adhesive 4 was obtained in the same manner as in Example 3. Similarly to the above, an evaluation board having an adhesion area of about 60% was prepared.

(Comparative Example 1)
The evaluation substrate used in Example 1 was used for evaluation without being filled with the reinforcing adhesive.

(Comparative Example 2)
Using the reinforcing adhesive 1 used in Example 1, an evaluation substrate filled with 100% by a dispenser was prepared.
(Comparative Example 3)
Benzoic acid 10 was prepared by reacting benzoic acid (reagent grade 1 manufactured by Kanto Chemical Co., Ltd.) and 3,4-dihydro-2H-pyran (manufactured by Kanto Chemical Co., Ltd.) of reinforcing adhesive 3 used in Example 3 in advance. An evaluation substrate having an adhesion area of about 60% was prepared in the same manner as in Example 3 except that the parts were replaced by parts by weight.

(Comparative Example 4)
Evaluation board having an adhesion area of 80%, which was carried out in the same manner as in Example 3, except that cyclohexyl = 4-methylbenzenesulfonate of reinforcing adhesive 4 used in Example 4 was replaced with 10 parts by weight of p-toluenesulfonic acid. Prepared.

  Table 1 shows the composition of the compositions of Examples and Comparative Examples. In the table, each compounding amount represents “part by weight”.

  Moreover, the following items were evaluated about the composition obtained by the Example and the comparative example. The results are shown in Table 2. The raw materials used and the evaluation methods are as follows.

2. Evaluation method (1) Viscosity (25 ° C.)
It measured with the E-type viscosity meter (made by Toki Sangyo Co., Ltd.). The rotor model was a 1 ° 34 'cone.

(2) Gel time The time required for a composition to gelatinize was measured using the 150 degreeC hotplate.

(3) Connection reliability during heat treatment A heat cycle treatment (-40 ° C / 125 ° C for 30 minutes each for one cycle) was performed. The presence or absence of BGA connection was measured every 10 cycles, and the number of cycles when continuity failure occurred was measured.

(4) Connection reliability at impact (25 ° C.) = Repeated bending test Both ends were fixed so that the width of the circuit board was 80 mm, and the operation of returning the center of the circuit board by 5 mm was repeated. Every time 1000 cycles were performed, the presence or absence of BGA connection was measured, and the number of cycles when a continuity failure occurred was measured.

(5) Repairability After heating to 250 ° C. to dissolve the solder bump joint, BGA was peeled off with tweezers, and workability when removing the composition from the circuit board was measured. The evaluation criteria are as follows.
A: BGA and the composition could be easily removed from the circuit board, and peeling of the surface resin of the circuit board did not occur.
X: It was difficult to remove BGA and the composition from the circuit board, and peeling of the surface resin of the circuit board occurred.
(6) Preservability The viscosity (25 ° C.) after standing at 40 ° C. for 1 week was measured with an E-type viscometer (manufactured by Toki Sangyo Co., Ltd.) in the same manner as in (1), and the change from the initial value was measured.
○: Less than twice the initial value △: More than twice the initial value

Examples 1 and 2 are one-part epoxy resin compositions of the present invention containing a compound having a latent active group, while maintaining curability and connection reliability at the time of heat treatment at a level that can be normally used, It became excellent in storage stability. This proves that the composition of the present invention has excellent connection reliability and repairability at the time of impact.
In Examples 5 and 6, the storage stability was slightly lowered due to the presence of unprotected carboxylic acid or sulfonic acid in the acid anhydride.
On the other hand, in Comparative Example 1, since no reinforcing adhesive was used, the result was inferior in connection reliability. In Example 2, the completely filled material had connection reliability due to the influence of voids due to volatile matter. The result was inferior.

  The present invention provides a one-pack type epoxy resin composition for underfill sealing having a compound or oligomer or polymer having a latent functional group, whereby the adhesion area is small, that is, the amount used is small. At least, it can be suitably applied as an underfill sealing material that can improve the connection reliability and repairability at the time of impact in a balanced manner.

1 is a cross-sectional view schematically showing an example in which solder balls are bonded with dots in the present invention, and a plan view in a state where a semiconductor element is removed. FIG. 3 is a cross-sectional view schematically showing an example in which solder balls are bonded together with a wire in the present invention, and a plan view in a state where a semiconductor element is removed. 1 is a cross-sectional view schematically showing an example in which the periphery of a solder ball is bonded in the present invention and a plan view in a state where a semiconductor element is removed. FIG. 4 is a cross-sectional view schematically showing an example in which the solder balls are wrapped in a linear state in the present invention, and a plan view in a state where a semiconductor element is removed. FIG. 4 is a cross-sectional view schematically showing an example in which a solder ball is wrapped in a state of being wrapped in the present invention and a plan view in a state where a semiconductor element is removed.

Explanation of symbols

1 Semiconductor Element 2 Adhesive 3 Solder Ball 4 Substrate

Claims (4)

A semiconductor device having a structure in which a reinforcing adhesive is filled between a semiconductor element having solder bumps for electrical bonding to a substrate, wherein the reinforcing adhesive has a fillable area of 5 to 95. %, And at least one unfilled space from the center of the semiconductor element to the outer periphery, and the reinforcing adhesive is a latent compound that generates carboxylic acid and sulfonic acid by heating. And / or a semiconductor device. The semiconductor device according to claim 1, wherein the reinforcing adhesive is a thermosetting resin composition. 3. The semiconductor device according to claim 2, wherein the thermosetting resin composition is one or more resin compositions selected from the group consisting of an epoxy resin composition, a cyanate resin composition, and a maleimide resin composition. 4. The semiconductor device according to claim 3, wherein the reinforcing adhesive is a thermosetting resin composition having flux activity.

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