JPH0823005A - Resin sealed semiconductor device and its manufacturing method, and sealing resin sheet - Google Patents

Abstract

PURPOSE:To make it possible to release a resin sealed semiconductor device easily from a mold without lowering bonding strength, by using a sealing resin sheet with different distribution of compounding agents between one face and the other face to the semiconductor device. CONSTITUTION:An element 5 pasted with a positive-side sealing resin sheet 1 and a negative-side sealing resin sheet 2 on the positive and negative sides is portion in portion in a mold. The sealing resin sheet 1 includes laminated resin sheets 1a and 1b with different concentration of compounding agents, and the sealing resin sheet 2 includes laminated resin sheets 2a and 2b also with different concentration of compounding agents. Then, the resin sheets 1a and 2a are put in contact with the element 5, while the resin sheets 1b and 2b are put in contact with the mold. A frame 7 is clamped by outer molds 8a and 8b and the sheet is pressed and hardened on the element 5 in a compression molding step.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a resin-encapsulated semiconductor device, a semiconductor device manufactured thereby, and a semiconductor-encapsulating resin sheet.

[0002]

2. Description of the Related Art In recent years, resin-encapsulated semiconductor devices have become larger in package size as semiconductor devices have become highly integrated, while the trend toward thinning has become stronger as the mounting space becomes finer. In addition, ASIC (Application Spec)
As represented by if ICs), semiconductor devices are becoming highly integrated and operating at high speed, and the amount of heat generated during operation is increasing. Therefore, a resin sealing technique having high thermal conductivity is desired so that this heat can be easily released to the outside of the semiconductor device via a heat sink or a mounting substrate. As a result of the diversification of package types, the number of types of resin-encapsulated semiconductor devices increases, but the production volume of each type tends to decrease. Establishing a manufacturing method is desired.

As a method of manufacturing a resin-sealed semiconductor device, a transfer molding method using an epoxy resin as a sealing resin is widely used. However, in the transfer molding method, the resin encapsulation process is a batch process, and it is difficult to put it in-line, which is not suitable for high-mix low-volume production.

As a method of improving this point, a method of supplying a sealing resin as a prepreg sheet has been proposed (JP-A-2-257662). In this method, resin sheets for sealing are arranged on both sides of a semiconductor element, and they are heated and pressure-bonded by a mold. This method is suitable for large-scale packages and high-mix low-volume production because it can be in-lined and thin-packaged.

[0005]

However, while certain compounding agents are used to improve resin properties, the compounding agents may reduce other properties.

For example, generally, in the case of molding using a mold such as transfer molding, there is a problem of releasability between the mold and the resin. If the releasability is poor, burrs may occur, and it is difficult to obtain a good package shape. Therefore, a release agent component such as wax is generally added to the sealing resin in order to improve the release property. On the other hand, however, addition of the release agent tends to cause peeling between the semiconductor element and the sealing resin. Therefore, cracks are likely to occur, leading to a reduction in moisture resistance and a reduction in reliability of the semiconductor device.

In order to solve this problem, for example, a method of using a composite sheet in which a metal sheet, a ceramic sheet or a resin sheet is placed outside and a sheet made of a resin which is melted in a sealing process and directly covers a semiconductor element is provided inside is proposed. (JP-A-2-257662). With this method, the mechanical strength is improved, and since the outer layer is not melted, there is no problem of releasability from the mold. However, the bonding interface between different types of sheets is easily peeled off, and there is a problem in reliability. Similarly, in consideration of improving strength, it has been proposed to alternately stack prepreg layers and glass fiber layers (US Pat. No. 46).
No. 80617), the problem of releasability from the mold is not solved.

By the way, an important characteristic required for the sealing resin is high thermal conductivity. This is because it is necessary to release the heat generated from the semiconductor element to the outside as described above. For this reason, a sealing resin for transfer molding generally contains a filler having high thermal conductivity. However, since the addition of the filler reduces the fluidity of the resin, there is a problem that molding with a die becomes difficult, and there is a problem that the strength is reduced.
Naturally, the amount added is limited, and it is difficult to obtain sufficient thermal conductivity. Also, this filling material is
It is likely to cause damage to the leads and the element surface.

It has also been proposed to use a resin sheet made of a resin having a low stress and a low viscosity on the surface of the element and a resin sheet made of a resin having a high thermal conductivity, a high strength and a high viscosity on the back surface of the element (Japanese Patent Laid-Open No. Hei 10 (1999) -242242) 5-175264). Although this publication does not disclose any specific means, when sheets made of different base resins are used, the interfaces between the front and back sheets are easily peeled off, and the reliability is not sufficient.

Further, when a curable resin is used as the sealing resin, it is essential to add a curing accelerator, and it is preferable to add a large amount of the curing accelerator in order to improve productivity, but a large amount is not added. This causes the curing accelerator of the reaction to remain. The presence of a large amount of this curing accelerator on the surface of the semiconductor element may lead to corrosion of wiring or the like.

Further, it is essential to add a flame retardant to the sealing resin in order to improve safety. The presence of a large amount of this flame retardant on the surface of the semiconductor element may cause corrosion of the wiring.

As described above, various characteristics are required as the sealing resin and various additives are mixed, but they have contradictory characteristics and the requirements are not always satisfied for each characteristic.

The present invention has been made in consideration of the above points, and is separated from the mold without impairing various characteristics required of the sealing resin, for example, other characteristics such as adhesive strength with a semiconductor element. It is an object of the present invention to provide a resin-sealed semiconductor device that can improve moldability and a method for manufacturing the same.

Another object of the present invention is to provide a resin-encapsulated semiconductor device capable of improving thermal conductivity without deteriorating various properties required of an encapsulating resin, for example, other properties such as moldability, and a method of manufacturing the same. The purpose is to provide.

Another object of the present invention is to provide a resin-encapsulated semiconductor device which can improve productivity without lowering reliability and a method for manufacturing the same.

Another object of the present invention is to provide a resin-sealed semiconductor device capable of improving flame retardancy without lowering reliability and a method for manufacturing the same.

Another object of the present invention is to provide a resin-encapsulated semiconductor device which can improve reliability during solder mounting, and a method of manufacturing the same.

[0018]

The present invention provides a resin encapsulation which comprises a step of disposing a sealing resin sheet on the surface of a semiconductor element and a step of melting and curing the sealing resin sheet in a mold. A method of manufacturing a static-type semiconductor device, wherein the encapsulating resin sheet has a distribution of a compounding agent different between a surface in contact with a semiconductor element and another surface. is there.

The present invention also provides a method of manufacturing a resin-encapsulated semiconductor device, which comprises a step of disposing a sealing resin sheet on the surface of a semiconductor element and a step of melting and curing the sealing resin sheet in a mold. The method for producing a resin-encapsulated semiconductor device is characterized in that the encapsulating resin sheet has a different distribution of the compounding agent in a region in contact with the semiconductor element and the lead wire and in other regions.

The present invention relates to a resin-encapsulated semiconductor device including a step of disposing a sealing resin sheet on the surface of a semiconductor element including an EPROM and a step of melting and curing the sealing resin sheet in a mold. A method of manufacturing a resin-encapsulated semiconductor device, characterized in that the distribution of the colorant is different between the part in contact with the EPROM element and the other part.

The present invention is a method of manufacturing a resin-encapsulated semiconductor device, which comprises a step of disposing a sealing resin sheet on the surface of a semiconductor element and a step of melting and curing the sealing resin sheet in a mold. A method for manufacturing a resin-encapsulated semiconductor device, wherein the encapsulating resin sheet has an adhesive force between a surface in contact with an element and an element is larger than an adhesive force between a surface on the opposite side of the element and a mold. Is.

The present invention is a resin-encapsulated semiconductor device comprising a sealing resin portion and a semiconductor element sealed with the sealing resin portion, wherein the sealing resin portion is in contact with the semiconductor element. A resin-encapsulated semiconductor device comprising a stopping resin layer and an encapsulating resin layer located outside the semiconductor device, wherein each encapsulating resin layer has a different distribution of a compounding agent contained therein. Is.

The present invention is a resin-sealed semiconductor device comprising a sealing resin portion and a semiconductor element sealed by the sealing resin portion, wherein the sealing resin portion is on the upper surface of the semiconductor element. It is composed of a first resin layer and a second resin layer on the lower surface of the semiconductor element, a: coefficient of thermal expansion of the first resin layer (K ⁻¹ ) b: elastic modulus of the first resin layer (Pa) c: resin thickness of first resin layer (mm) d: coefficient of thermal expansion of second resin layer (K ^-1 ) e: elastic modulus of second resin layer (Pa) f: second resin layer The resin-encapsulated semiconductor device has a resin thickness (mm) of 0.8 <(abc) / (def) <1.2.

The present invention is a resin sheet for encapsulation, which is disposed on the surface of a semiconductor element and seals the semiconductor element by being melted and cured, wherein the resin sheet is a resin sheet on the surface in contact with the element and on the other surface. The distribution of the compounding agent contained in is different, and the compounding agent is at least one selected from a curing accelerator, a colorant, a release agent, an adhesion promoter, a flame retardant and a filler. Is a resin sheet for sealing.

The present invention will be described in detail below.

In the present invention, in order to simultaneously satisfy the contradictory characteristics of the compounding agent, the composition of the resin sheet is not uniform, and the concentration and kind of the compounding agent are partially changed. That is, it is possible to improve the characteristics of a certain type of compounding agent by increasing the concentration in a specific portion, and suppress the deterioration of the characteristic by decreasing the concentration of this compounding agent in another portion.
Of course, some kind of compounding agent may be compounded only in a specific part.

However, the composition of the resin cannot be partially changed in this way by using the transfer molding method.

In order to produce a resin sheet having a changed composition, a first resin sheet and a second resin sheet which have the same basic resin composition but only the compounding agent are prepared are prepared. The first resin sheet and the second resin sheet are pressure-bonded and integrated with each other to form a sealing resin sheet. The encapsulating resin sheet can be produced by changing the concentrations of the compounding agents of the first resin sheet and the second resin sheet.

In the present invention, since the resin sheet is melted at the time of molding and mixed at the interface between the first sheet and the second sheet, it does not peel off at this interface after molding. Therefore, the compositions of the first and second sheets need not be exactly the same, but they must be melt mixed.

The concentration and type of the compounding agent may be changed in the thickness direction between one side and the other side of the sheet, or may be changed between a part of the area and another area. Further, the change of the compounding agent may be continuous or stepwise.

In the present invention, the semiconductor element may be sandwiched between two resin sheets having different composition of the compounding agent for sealing. In this case, the composition of each encapsulating resin sheet is uniform, but the composition of the resin is different between the active surface side and the back side of the semiconductor element after encapsulation.

A method of manufacturing the resin-sealed semiconductor device of the present invention will be described with reference to FIG. FIG. 1 is a conceptual diagram in which assembly to sealing are performed in a continuous process.

The film carrier 7 is continuously sealed while being moved between the supply reel 100 and the take-up reel 500. This apparatus includes a supply reel 100, a semiconductor element mounting portion 200, a sheet sticking portion 300 for feeding and sticking two uncured resin sheets from above and below, and a press molding portion 40.
0 and a take-up reel 500.

The external lead structure such as a film carrier on which the semiconductor element is mounted and the sealing sheet can be supplied in a reel system. For example, by supplying them with reels so that they correspond to each other, and by assembling and sealing, the semiconductor device assembly to sealing can be performed in a continuous process.

In the manufacturing process, first, the semiconductor element 5 is connected face down on the film carrier 7 via the bumps 4 while the chip mounting portion 200 is aligned. After that, the uncured resin sheet is attached to the upper surface side and the lower surface side of the semiconductor element by the sheet attaching section 300. However, in order to frame the resin-sealed portion of the external lead structure with good adhesion using a mold, it is desirable to supply the resin sheet for sealing in a cut form. Further, the press molding unit 40
Mold 401 heated by heater 402 at 0
In-mold compression molding. Then, the winding reel 500 is used for winding. Alternatively, only the active surface side of the semiconductor element may be sealed with a sealing resin sheet.

The sticking part 300 is equipped with a container for accommodating and stacking the uncured resin sheets for sealing and a chip position detector capable of automatically detecting the position of the chip. It is an apparatus that can supply the uncured resin sheet for sealing to the chip and can automatically supply the resin sheet. Further, the sticking part 300 may be provided with a device for preheating either the chip or the uncured resin sheet for sealing in order to stick the uncured resin sheet for sealing to the chip. What is the preheating step? By heating the chip or the resin sheet in the optimum temperature profile, the resin sheet softens and can be attached to the chip. The heating method is not particularly limited, but preferably, there is a method of irradiating infrared rays, a method of using an oven, or the like. Further, in the method of heating with light, it is preferable to attach a condenser lens for efficient heating.

The molding process in the press molding section 400 will be described with reference to FIG.

First, as shown in FIG. 2A, the element active surface side sealing resin sheet 1 is attached to the active surface side of the element 5, and the element back surface side sealing resin sheet 2 is attached to the back surface side of the element. Place things in place in the mold. Here, the sealing resin sheet 1 is a laminate with the resin sheets 1a and 1b having different concentrations of the compounding agent. The sealing resin sheet 2 is also a laminated body with the resin sheets 2a and 2b having different concentrations of the compounding agent. The resin sheets 1a and 2a are resin sheets in contact with the element, and the resin sheets 1b and 2b are resin sheets in contact with the mold. Then, as shown in FIG. 2B, the frame 7 is clamped by the outer molds 8a and 8b. Finally, as shown in FIG. 2 (c), the encapsulating resin sheets 1 and 2 are compression-molded by the inner molds 9 a and 9 b, and the encapsulating resin sheet is cured while being pressed against the element 5. Note that FIG. 2D is a perspective view of the molds 8 and 9.

As a specific method for curing the uncured resin, in the case of a thermosetting resin, a method of heating a mold used in integral molding, or a method of selectively heating only the uncured resin by induction heating is used. And the like. Further, after-curing is desirable to improve various characteristics of the package after molding.

In the step of molding and curing the encapsulating resin sheet at the same time in the mold according to the present invention to encapsulate the semiconductor element, the above temporarily fixed encapsulating resin sheet is pressed, heated or photocured. Is a step of curing in a mold to seal the semiconductor element.

The mold that can be used in the present invention has a shape that is equal to or slightly larger than the shape of the resin sheet, and the volume of the mold is slightly smaller than the total volume of the two resin sheets. It is desirable to use a material in which the resin is pressed during molding. Further, it is desirable to provide the mold with an air vent that releases excess resin during pressurization. Further, it is desirable that the structure is such that the inside of the mold can be depressurized in order to prevent generation of voids during compression molding of the semiconductor element and the sealing resin sheet. Further, a method in which two concave molds are opposed to each other so as to have a space inside, or a method in which a frame-shaped mold and a press mold are combined to perform pressure molding may be used. With this method, the sealing process can be performed in-line. Therefore, the manufacturing method is very suitable for high-mix low-volume production.

As the material of the mold, metal, ceramic, heat resistant plastic, glass or the like can be used.
Particularly when a photocurable resin is used, it is preferable that the mold is made of a translucent member such as silica glass so that light can be irradiated through the mold.

The type of semiconductor device used in the present invention is not particularly limited. Even if it is wire-bonded, TAB (Tape Automated Bond)
ing), the structure of the present invention is most suitable for a surface-mounted semiconductor device because the semiconductor package is thin and the chip area is large.

In the resin-sealed semiconductor device of the present invention,
For the types of external lead structure and semiconductor device,
There is no particular limitation. For example, the external lead structure may include a lead frame, a film carrier, a circuit board having external pins, and the like.

The resin composition according to the present invention will be specifically described. Examples of the resin simple substance that can be used in the resin-encapsulated semiconductor device of the present invention include thermosetting resins, photocurable resins, engineering plastics, and the like.

Examples of the thermosetting resin include epoxy resin, polyimide resin, maleimide resin, silicone resin, phenol resin, polyurethane resin and acrylic resin. These resins may be used alone or in combination, and in these resins, a curing agent, a curing accelerator, a plasticizer, a colorant, a flame retardant, a filler,
It may also contain a low stress additive and various other additives.

Among the thermosetting resins, epoxy resin is preferable as the resin having high adhesiveness to the device. Any epoxy resin may be used as long as it has two or more epoxy groups in one molecule, but an epoxy resin having an epoxy equivalent of 250 or less is preferable from the viewpoint of heat resistance. For example,
Phenol novolac type epoxy resin, cresol novolac type epoxy resin, naphthol novolac type epoxy resin, bisphenol A type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, alicyclic epoxy resin, phenol or alkylphenols and hydroxybenzaldehydes Tris (hydroxyphenyl) alkane-based epoxy resin, tetra (hydroxyphenyl) alkane-based epoxy resin obtained by epoxidizing a condensation product with
2 ', 4,4'-tetraglycidyl benzophenone, triglycidyl ether of para aminophenol, polyallyl glycidyl ether, 1,3,5-triglycidyl etherified benzene, 2,2', 4,4'-tetraglycididoxy Examples include benzene. These resins may be used alone or in combination of two or more.

Further, in order to improve the flame retardancy of the package, it is preferable to use various halogenated epoxy resins, especially brominated epoxy resins. Examples thereof include brominated bisphenol type epoxy resins and brominated phenol novolac type epoxy resins.

Further, a biphenyl type epoxy resin represented by the following general formula (I) is preferable. This epoxy resin not only improves the adhesiveness of the cured product according to the present invention, but also has the effect of improving the thermal shock resistance.

[0050]

Embedded image Where each R is H or CH ₃ , and R ² , R ³
, R ⁵ , R ⁶ , R ^{2 ′} , R ^{3 ′} , R ^{5 ′} and R ^{6 ′} are H and C
1, 1, Br or an organic group such as methyl, ethyl, isopropyl, butyl or phenyl is shown. n is an integer of 0-5.

Specific examples of the epoxy resin represented by the general formula (1) are 4,4'-bis (2,3-epoxypropoxy) biphenyl and 4,4'-bis (2,3-epoxypropoxy). -3,3'-5,5'-tetramethylbiphenyl, 4,4'-bis (2,3-epoxypropoxy) -3,3'-5,5'-tetramethyl-2-chlorobiphenyl, 4, 4'-bis (2,3-epoxypropoxy) -3,3'-5,5'-tetramethyl-2-bromobiphenyl, 4,4'-bis (2,3-epoxypropoxy) -3,3 '-5,5'-Tetraethylbiphenyl,4,4'-bis (2,3-epoxypropoxy)-
3,3'-5,5'-tetrabutylbiphenyl, 4,4
′ -Bis (2,3-epoxypropoxy) -3,3′-
5,5'-tetraphenyl biphenyl and the like can be mentioned.

Further, preferred epoxy resins having high adhesiveness include bisphenol A type epoxy resin and bisphenol F type epoxy resin.

In order to further improve the crack resistance, it is preferable to use a trifunctional epoxy resin represented by the following general formula (II).

[0054]

Embedded image Here, R ⁷ and R ⁸ represent H or an organic group such as an alkyl group having 1 to 20 carbon atoms. n is an integer of 0-10.

Specific examples of the epoxy resin represented by the general formula (II) include EPPN-502 (trade name, manufactured by Nippon Kayaku Co., Ltd., softening point 70 ° C., epoxy equivalent 170), YL-93.
2H (trade name manufactured by Yuka Shell, softening point 63 ° C., epoxy equivalent 171), ESX-221 (trade name manufactured by Sumitomo Chemical, softening point 85 ° C., epoxy equivalent 210) and the like.

These epoxy resins are usually molded by advancing the curing reaction with a curing agent. The curing agent may be any one generally known as a curing agent for epoxy resins. For example, phenol novolac resins, cresol novolac resins and other novolac type phenolic resins having two or more phenolic hydroxyl groups, phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride and other acid anhydrides, triethylenetetramine, metaphenylenediamine, etc. Amines, and the like.

Examples of the photocurable resin include polyester acrylate, epoxy acrylate, polyurethane acrylate, polyether acrylate, oligo acrylate, alkyd acrylate and polyol acrylate. Further, as a photoinitiator for these photocurable resins, acetophenone, benzophenone,
Examples thereof include Michler's ketone, benzine, benzoin, benzoin alkyl ether, benzyl methyl ketal, tetramethyl thiuram monosulfide, thioxanthones and azo compounds.

Examples of engineering plastics include polyacetal, polycarbonate, polyamides such as nylon 6 and nylon 66, fluorine-based polymers such as ethylene-tetrafluoroethylene copolymer and polytetrafluoroethylene, and polyoxybenzoyl. Can be mentioned. As the compounding agent added to the resin component, it is possible to use those which are usually used.

Examples of the filler having a high thermal conductivity to be added to the components according to the present invention are quartz glass, fused silica, crystalline silica, glass, talc, potassium sulfate, magnesia, mica, beryllium oxide, aluminum nitride, magnesium oxide and nitride. Examples thereof include inorganic fillers such as boron, silicon nitride and aluminum oxide, and powders of various metals such as aluminum powder and copper powder whose surface is subjected to antioxidation treatment and alloy powders thereof. Any other inorganic powder that can be used as a semiconductor sealing resin may be used, and examples thereof include fused silica and crystalline silica. These inorganic materials have a crushed shape obtained by crushing a large inorganic material, a shape close to a true sphere or a subspherical shape, a shape with only a cut edge removed in the crushing process, There are flat ones, fibrous ones, and ones in which the same kind or different kinds of crystals are grown on the surface of crushed inorganic powder to form a continuous surface. When these inorganic materials are used for the semiconductor sealing resin, they may be used alone or in combination of two or more kinds.

Further, in order to improve the mold releasability from the mold, a hydrocarbon wax, a fatty acid wax,
It is also effective to add a fatty acid amide wax, an ester wax or the like to the sealing resin or apply it to the contact surface with the mold. As a specific example, from the viewpoint of moisture resistance, carnauba wax, ester wax such as montan wax is preferable, and other long-chain carboxylic acids such as stearic acid, palmitic acid, zinc stearate, calcium stearate and metal salts thereof, Examples thereof include low molecular weight polyethylene wax. These release agents may be used alone or in combination.

The curing accelerator that can be used in the present invention can be used without particular limitation as long as it can accelerate the curing reaction of the resin component. Taking an epoxy resin as an example, examples of the curing accelerator include various amines, imidazoles, diazabicycloalkenes, organic phosphines, zirconium alcoholates, zirconium chelates and the like. Specifically, as amines, N, N-dimethylcyclohexylamine,
N-methyldicyclohexylamine, triethylenediamine, diaminodiphenyl sulfone, dimethylaminomethylphenol, benzyldimethylamine, trisdimethylaminomethylphenol and the like are used as imidazoles such as 2-methylimidazole, 2-phenylimidazole, heptadecylimidazole, 2- Heptadecyl imidazole, 2-ethyl imidazole, 2-ethyl-4-
Methylimidazole and the like are used as diazabicycloalkenes and 1,8-diazabicyclo (5,4,0) undecene-7 (DBU), a phenol salt of DBU (for example, U
-CAT SA No. Examples of the organic phosphines such as 1) include triphenylphosphine (TPP), tributylphosphine, tricyclohexylphosphine, and methyldiphenylphosphine.

Among these curing accelerators, triphenylphosphine (TPP) and heptadecyl imidazole, which show excellent electrical characteristics in the obtained resin-encapsulated semiconductor device, are particularly preferable.

In the present invention, as the flame retardant, halogen type, phosphorus type and inorganic type flame retardants can be used. Halogen-based flame retardants are mainly classified into bromine-based and chlorine-based flame retardants. Preferred brominated flame retardants include brominated bisphenol A type epoxy resin and tetrabromobisphenol A (T
BA), 2,2-bis (4-hydroxy-3,5-dibromobenzene (HBB), tris (2,3-dibromopropyl) isocyanurate (TAIC-6B), 2,2
-Bis (4-hydroxyethoxy-3,5-dibromophenyl) propane (TBA-EO), decabromodiphenyl oxide (DBDPO), halogen-containing polyphosphate and the like. The bromine type has a higher flame retardant effect than the chlorine type, and has a large effect in combination with antimony trioxide. A preferred chlorine-based flame retardant is chlorinated paraffin. A brominated bisphenol A type epoxy resin is particularly preferably used as the halogen-based flame retardant.

Preferred phosphorus-based flame retardants are ammonium phosphate, triglycidyl phosphate (TCP), triethyl phosphate (TEP), tris (β-chloroethyl) phosphate (TCEP), trischloroethyl phosphate (CLP), trisdichloropropyl phosphate. (CRP), cresyl diphenyl phosphate (CDP), xylenyl diphenyl phosphate (X
DP), acidic phosphoric acid esters, nitrogen-containing phosphorus compounds and the like.

Preferred inorganic flame retardants include red phosphorus,
There are tin oxide, antimony trioxide, zirconium hydroxide, barium metaborate, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, calcium aluminate hydrate, and the like. Among them, inorganic flame retardants that are particularly preferable to be used , Antimony trioxide and aluminum hydroxide.

The kinds and concentrations of the compounding agents such as the curing accelerator, the flame retardant, the filler and the colorant described above may be changed individually or at the same time with each other.

Next, a method of manufacturing the resin-encapsulated semiconductor device of the present invention will be described. The resin-encapsulated semiconductor device of the present invention is obtained by disposing the encapsulating resin sheet on at least one side or both sides of the element, and molding and curing in a mold.

First, a sealing resin sheet made of the uncured resin composition according to the present invention will be described. The sealing resin sheet includes, for example, an epoxy resin, a curing agent, a curing accelerator,
It can be prepared by crushing, mixing, melting and rolling a filler, a flame retardant, a release agent, a colorant, a low stress additive, and other materials. The resin sheet thus formed is, for example, a resin sheet having good thermal conductivity and a resin sheet having poor thermal conductivity but excellent moldability, which are superposed on each other and thermocompression bonded by a press. Since the obtained sealing resin sheet is very brittle, in order to cut it to a predetermined size, first heat the resin sheet on release paper and cut it by pressing a cold blade, or the resin sheet is at room temperature. Cut using the heated blade as it is. The heating temperature of the resin sheet or the blade is preferably 70 ° C to 130 ° C. This is because the resin melts sufficiently at this temperature but the hardening does not proceed.

The method of inclining or multilayering the amount and type of the compounding agent of the encapsulating resin sheet is as follows. A plurality of resin sheets having different compositions are superposed and thermocompression bonded, and then the resin sheet is cut into a prescribed size. There is a way. When this method is used, a resin having the same composition as that on the element is exposed on the side surface of the package, but this is effective for mass production of resin sheets. As another sheet creation method,
As shown in FIG. 3, there is a method in which a large resin sheet 21 and a small resin sheet 22 in which the type and concentration of the curing accelerator are changed are overlapped and thermocompression bonded. This method has an advantage that different resin compositions can be arranged only on the element.

In the present invention, the resin sheet may be discontinuously multilayered or continuously graded. However, when the concentration of the compounding agent is continuously graded, the interface becomes smaller than that of the multilayered sheet. Since it does not exist, the characteristics of the resin improve.

Further, a method for making a sheet in which the concentration or kind of the compounding agent is inclined will be described with reference to FIG. As shown in FIG. 4, when a plurality of resin sheets 19a, 19b and 19c in which the concentration and type of the compounding agent 18 differ stepwise are overlapped and thermocompression bonded by a press, the resin melts and mixes between the sheets. Thus, the sheet 20 in which the concentration and the type are continuously changed is obtained. The encapsulating resin sheet in which the concentration and kind continuity of the inclined compounding agent 18 are improved can be obtained by increasing the number of resin sheets to be stacked and reducing the thickness of each sheet.

There is no clear distinction between the sheet in which the amount and kind of the filler are discontinuously multi-layered and the sheet in which the filler is continuously inclined, and a large number of thin sheets are superposed on each other and slowly and at high temperature under high pressure. When thermocompression bonding is performed, a continuously inclined sheet is formed, and when thicker sheets are stacked and thermocompression bonding is performed at low pressure quickly and at low temperature, a discontinuous multilayered sheet is formed.

As described above, by blending the necessary compounding agents only in the necessary portions of the resin sheet, it is possible to achieve both of the contradictory properties.

Further, in the manufacturing method of the present invention, the semiconductor chip and the encapsulating resin sheet can be supplied by the lead frame or line, so that the semiconductor chip can be supplied by the film carrier. As a result, compared with the transfer molding method in which batch processing is essential, the sealing process can be completely in-line, and the semiconductor device assembly to sealing can be performed in a continuous process. Therefore, the manufacturing method of the present invention is a flexible manufacturing method suitable for high-mix low-volume production.

Further, as described above, since the encapsulating resin sheet is encapsulated in advance in a state of being brought into contact with the semiconductor chip and the leads, the uncured resin can be used as compared with the transfer molding method. Even if the viscosity at the time of melting is large, good sealing can be performed.

As a result, in the method of manufacturing the resin-sealed semiconductor device having the structure according to the present invention, the manufacturing process can be simplified and a resin-sealed semiconductor device having a good appearance can be obtained.

For example, the releasability from the mold is taken up. The characteristic that is contrary to the releasability is the adhesiveness between the semiconductor element and the sealing resin.

When the semiconductor device is surface-mounted and soldered to a substrate, the entire device is usually 200-240.
It is exposed to a high temperature atmosphere of ℃ for 5 to 90 seconds. When subjected to such a severe thermal shock, vaporization of water taken in the package may cause the cracking of the sealing resin. In particular, when the adhesion between the resin and the element is weak, the interface between the resin and the element peels off and water accumulates there, and explosive vaporization of this water causes large cracks. If the adhesive strength between the sealing resin and the semiconductor element is sufficiently large, the occurrence of cracks can be prevented. On the other hand, usually, the resin composition contains a release agent such as wax for the purpose of improving the releasability from the mold, and therefore the adhesive strength between the resin and the element is not sufficient. There wasn't.

According to the present invention, by disposing a release agent at a high concentration on the mold surface side of the encapsulating sheet, it is possible to increase the adhesive strength with the element while maintaining the desired releasability. . Conversely speaking, a desired release agent can be obtained in a state having the maximum adhesive strength (for example, no element side release agent).

For example, the above-mentioned resin sheets having different concentrations of the release agent may be stuck together, and the high-concentration sheet may be arranged on the mold side.

It is also possible to simply apply the release agent to the side surface of the mold.

Further, the same effect can be obtained by using an adhesiveness-imparting agent instead of the release agent. However, in this case, the concentration is increased on the element side or is applied only on the side surface of the element. It is also possible to use it together with a release agent.

The thickness of the resin layer containing a large amount of release agent is 1
0 μm or more is desirable.

Further, the thickness of the resin layer containing the adhesion-imparting agent is preferably 10 μm or more.

For example, as shown in FIG. 2, a resin sheet 1b containing a release agent with a high concentration and a resin sheet 1a with a low release agent concentration are laminated. The same effect can be obtained by applying a release agent on one side.

Further, the same effect can be obtained by changing the adhesiveness-imparting agent.

A metal chelate compound is preferably used as an adhesiveness-imparting agent to be contained in the resin composition constituting the element-side sheet or applied to the surface of the resin sheet in contact with the element. The metal chelate compound improves adhesiveness and water resistance. Such metal chelate compounds include Zr chelate, Ti chelate, A
1 chelate and the like. Examples of the Zr chelate compound include tetrakis acetylacetonato zirconium, monobutoxy tris acetyl acetonato zirconium, dibutoxy bis acetyl acetonato zirconium, tributoxy acetyl acetonato zirconium, tetrakis ethyl acetyl acetate zirconium, butoxy tris ethyl acetyl acetate zirconium, tributoxy. Monoethyl acetyl acetate zirconium, tetrakis ethyl lactate zirconium, dibutoxy bis ethyl lactate zirconium, bis acetyl acetonato bis ethyl acetyl acetonato zirconium, mono acetyl acetonato tris ethyl acetyl acetonato zirconium, mono acetyl acetonato bis ethyl acetyl acetonato butoxy Zirconium, bisacetylacetate Isocyanatoethyl bisethyl Lactobacillus isocyanatomethyl zirconium, and the like. Ti
Examples of the chelate and the Al chelate include compounds having a ligand such as β-diketone, hydroxycarboxylic acid, ketoester, ketoalcohol, and glycol. These additives may be used alone or in combination.

Next, the thermal conductivity will be taken up. The filler that is made of an inorganic material greatly contributes to the thermal conductivity.

For example, when an attempt is made to obtain a resin-encapsulated semiconductor device filled with a highly thermally conductive filler in order to reduce the amount of heat generated during operation, the viscosity that can be molded by transfer molding is 1
It is up to about 00 Pa · sec, and when the filling material is highly filled, the viscosity increases and it is difficult to form the filling material, and the filling amount is limited. On the other hand, if a heat conductive filler is added within a range that does not impair the moldability, ASICs that generate a large amount of heat in recent years
There is a problem in that a resin-encapsulated semiconductor device having high thermal conductivity corresponding to the above cannot be obtained.

The resin-encapsulated semiconductor device of the present invention is resin-encapsulated by using plural kinds of encapsulating resin compositions whose thermal conductivity is changed by changing the compounding ratio of the filler. A single package provides high reliability due to very high thermal conductivity and good formability not achievable by conventional methods. That is, the present invention separates the functions of moldability and thermal conductivity from a plurality of types of encapsulating resin compositions without making the moldability and thermal conductivity compatible with one type of resin composition as in the prior art. It is based on the finding that by doing so, it is possible to make the functions of one semiconductor device compatible with each other and further increase those functions to the limit.

In order to enhance the heat dissipation of the semiconductor element, it is required to highly fill the vicinity of the element with a high thermal conductive filler. However, since the surface of the element active surface side is very easily damaged by the filler, it is possible to highly fill the element back surface side only with this method, for example. In addition, a resin having a low viscosity and a small filler filling ratio is used because the portion contacting the lead or the wire is required to have high adhesiveness with the resin and is easily deformed.

The blending ratio of the filler varies depending on the kind of the filler, but is preferably 40 to 90% by weight. Further, in order to further reduce the thermal expansion coefficient and reduce damage to the chip surface, it is particularly preferably 60 to 85% by weight.

In the resin-encapsulated semiconductor device of the present invention, the arrangement of the first and second encapsulating resin compositions is not particularly limited, and may be on the upper and lower surfaces of the element or on only one surface. Each composition may be divided into a plurality of upper and lower surfaces.
The mode of arrangement of the sealing resin composition is shown in FIGS.

FIGS. 6A to 6D and TCP are TCP.
It is a (tape carrier package) type, and the pad portion on the active surface side of the element 5 and the frame (polyimide film carrier) 7 are connected via the bump 4 and the lead wire 3. These elements 5, bumps 4, and lead wires 3 are sealed with a first sealing resin composition 12 having a high filler filling rate and a second sealing resin composition 13 having a low filler filling rate.

In FIG. 6A, the first sealing resin composition 1
2 is arranged so as to contact the back surface and active surface of the semiconductor element 5. The part that contacts the lead 3 and the bump 4 is the second
The sealing resin composition 13 is disposed.

In FIG. 6B, the first sealing resin composition 12 extends to the side surface of the package.

In FIG. 6C, the first sealing resin composition 12 is arranged so as to be in contact with the active surface of the element, but the area is limited to the inside of the pad.

In FIG. 6D, the first sealing resin composition 12 on the back surface side in FIG. 6C is not used, but is sealed with the second sealing resin composition 13.

6 (e) to 6 (h) and 6 (j) are of the lead frame type, in which the die pad 10 and the leads 1 are shown.
It is composed of 1. The semiconductor element 5 is connected to the die pad 10 on the back surface, and the active surface of the element 5 is connected to the lead 11 via the wire 3. The first sealing resin composition 12 is below the die pad 10. The portion of the wire 3 is sealed with the second sealing resin composition 13.

In FIG. 6E, the first sealing resin composition 12 is limited only to the inside of the pad area on the active surface of the device.

In FIG. 6F, the first surface of the back surface of the semiconductor element 5 is shown.
The encapsulating resin composition 12 extends to the side surface of the package. That is, the structure is such that the element 5 and the wire 3 sealed by the first sealing resin composition 12 are sandwiched between the second sealing resin composition 13.

In FIG. 6G, the first sealing resin composition 12 is limited to the size of the element.

In FIG. 6 (h), the first sealing resin composition 12 on the upper side of the element is divided.

For the semiconductor package, aluminum, copper,
It is also possible to attach and seal the heat dissipation plates 14 and 15 of AlN or the like.

In FIGS. 6 (i) and 6 (j), a radiator plate is attached so as to be in contact with the first sealing resin composition 12.

Among a plurality of types of resin compositions having different thermal conductivity according to the present invention, at least one type of resin composition is a resin composition having a higher thermal conductivity than other resin compositions. . This first resin composition has a thermal conductivity of 5 W.
/ Mk or more is preferable. The higher the thermal conductivity is, the more preferable it is, and the more preferable range is 8 W / m.
K or higher is desirable.

Such a resin having a high thermal conductivity can be obtained by highly filling the high thermal conductive filler, and the preferable blending amount of the high thermal conductive filler of the first resin composition of the present invention is 60 volume. %
As described above, in order to further increase the thermal conductivity, it is preferable to add 70% by volume or more. In this case, the viscosity of the resin increases and the moldability is deteriorated, but at least the melt viscosity measured by the Koka flow tester is preferably 3000 Pa · s or less. If the value of the filling material is less than this, the reliability of the device is deteriorated.

Among the resin compositions according to the present invention,
For at least one type of resin composition, a resin composition having a higher moldability than other resin compositions is applied. The second resin composition preferably has a melt viscosity at 175 ° C. measured by a Koka type flow tester of 300 Pa · s or less. The melt viscosity is preferably low in order to reduce damage to the lead wire and the element surface and improve the moldability, and more preferably 1000 Pa · s or less. Since the second resin composition also does not serve as a heat barrier, it is desirable that a heat conductive filler is blended within a range that does not impair the moldability represented by the above-mentioned viscosity so that the heat conductivity is somewhat high. The magnitude of this thermal conductivity is preferably 0.5 W / mK or more. If the thermal conductivity is smaller than this value, it may serve as a thermal barrier and impair the heat dissipation of the semiconductor device.

In a semiconductor device after encapsulation, a structure in which the first resin composition is surrounded by the second resin composition, or a structure in which at least one surface is exposed to the outside of the device, By making the second resin composition completely bear the strength and moldability of the above, it becomes possible to further mix the high thermal conductive filler, and the preferable compounding amount in the first resin composition is 80 to 95% by volume. Can be increased up to. When the compounding amount of the high thermal conductive filler exceeds 95% by volume, the adhesiveness with the resin composition having good moldability is deteriorated, and cracks occur in the package during mounting of the semiconductor device such as solder reflow and infrared reflow. It becomes a factor and is not preferable.

According to the present invention, the function of the resin composition is separated into the thermal conductivity and the moldability to prepare the encapsulating resin composition excellent in the respective properties, and the encapsulating resin composition is composed of the respective resin compositions. By using the resin composition in combination, the two different requirements of high thermal conductivity and moldability that cannot be obtained with a uniform resin composition can be sufficiently satisfied. That is, the heat generated from the semiconductor element of the resin-encapsulated semiconductor device can be efficiently dissipated through the encapsulating resin layer having high thermal conductivity. In addition, in a high temperature atmosphere during mounting of a semiconductor package in which adhesion and resin strength are problems, a resin having good moldability can provide sufficient adhesion and resin strength.

Further, the high thermal conductive resin and the resin having good moldability are melt-cured together at the time of molding and become completely integrated at the interface. For this reason, the adhesive force between the resins becomes much stronger than the adhesive force with the ceramics or metal, and exhibits very good characteristics against package cracks in a high temperature atmosphere during mounting of the semiconductor device. Further, since the high thermal conductivity resin can have a coefficient of thermal expansion close to that of metal or ceramic, it can be integrated with the metal or ceramic at the time of molding. When manufacturing resin-encapsulated semiconductor devices, it is extremely easy to integrate by adopting a function-separated encapsulating resin structure that combines encapsulating resin with high thermal conductivity and encapsulating resin with good moldability. It is possible to supply a large number of packages which can be formed and have good adhesiveness between the semiconductor element and the sealing resin and extremely good thermal conductivity, at low cost.

As described above, according to the present invention, it is possible to easily manufacture a resin-encapsulated semiconductor device having an extremely high level of high thermal conductivity and good reliability, which has heretofore been impossible.

The size of the resin sheet having good thermal conductivity used on the active surface side of the semiconductor element is such that it is inside the inner lead of the semiconductor element connected to the lead structure or the pad portion to which the wire is connected. Is preferred.
This is because the high thermal conductive resin sheet has a high melt viscosity due to a high filling amount of the filler, and thus reduces the probability that the connecting portion of the semiconductor element is damaged.

In the present invention, the types and amounts of the fillers that can be changed in the present invention will be described below together with the function and effect of the items a) to f).

A) The amount of the resin composition in contact with the mold is increased, and the amount of the resin composition in contact with the device is decreased.

Generally, when the amount of the filler of the encapsulating resin composition is increased, the water absorption rate is lowered, while the thermal conductivity and the resin strength are improved, so that the resin encapsulation type semiconductor device reduces package cracks and scratches. Can be prevented. However, when the resin sheet is pressed against the element and pressed, there is a problem that if the amount of the filler is large, the bonding wires and inner leads are deformed and the element is often damaged.

In the present invention, a sealing resin sheet is prepared in which the amount of the resin composition in contact with the mold is large and the amount of the resin composition in contact with the element is small, and this sheet is used. By molding the package with this, it is possible to obtain a package having low water absorption, good thermal conductivity, improved strength, and less lead deformation and damage to the element. The resin composition in contact with the mold forms the resin portion on the outer peripheral portion of the package.

The thickness of the resin layer in which the amount of the filler in contact with the mold is increased is 30 μm in order to reduce the water absorption of the package.
The thickness of the resin layer contacting the element is preferably 30 μm or more in order to prevent deformation of the leads and wires.

The ratio of the filler of the resin portion on the outer periphery of the package to the total composition must be higher than the ratio of the filler of the resin portion contacting the element to the total composition, and the proportion of the outer periphery is the portion contacting the element. Is preferably 1.5 times or more, and more preferably 2 times or more in order to further improve the characteristics. Particularly, when it is 5 times or more, very good characteristics can be obtained.

B) Increase the amount of crushed filler in the resin composition in contact with the mold, and increase the amount of spherical filler in the resin composition for sealing in contact with the device.

Generally, if the amount of the crushed filler as the filler of the resin composition is increased, the package crack can be reduced due to the improvement of the resin strength, and the occurrence of burrs in the mold gap can be prevented. However, when the resin sheet is pressed against the element and pressed, if a crushed filler is used, the bonding wires and inner leads may be deformed, and the sharp corners of the filler may pierce the element, causing many problems. is there. On the other hand, when the spherical filler is used, the deformation of the leads and the damage to the element are small, but there is a problem that the burr is increased.

In the present invention, a sealing resin sheet is prepared in which the resin composition in contact with the mold contains a large amount of crushed filler and the resin composition in contact with the device contains a large amount of spherical filler. By molding the package using the sheet, it is possible to obtain a package having high strength, less burrs, and less lead deformation and damage to the element.

The thickness of the resin layer containing a large amount of the crushed filler in contact with the mold is preferably 30 μm or more in order to maintain the strength and prevent burrs. The thickness is preferably 30 μm or more in order to prevent deformation of the leads and wires.

The ratio of the resin portion of the outer peripheral portion of the package to the total composition of the crushed filler must be larger than the ratio of the resin portion of the resin portion contacting the device to the total composition of the outer peripheral portion. The ratio of the portion in contact with the element is 1.
It is preferably 5 times or more, and more preferably 2 times or more in order to further improve the characteristics. Particularly, when it is 5 times or more, very good characteristics can be obtained. Further, the ratio of the spherical filler to the total composition of the resin portion in contact with the element must be larger than the ratio of the spherical filler to the total composition of the resin portion of the outer peripheral portion of the package. The ratio is preferably 1.5 times or more the ratio of parts, and is preferably 2 times or more in order to further improve the characteristics. Particularly when it is 5 times or more, very good characteristics can be obtained.

C) A large amount of general-purpose filler is added to the sealing resin composition in contact with the mold, and a large amount of low α ray filler is used as a filler in contact with the device.

If a general-purpose filler is used for an element such as a memory when sealing a semiconductor package, the resin-sealed semiconductor device may malfunction due to α rays emitted by uranium or thorium contained in the filler. is there.

However, low α without uranium and thorium
The wire filler is extremely expensive as compared with a general-purpose filler, and it is required to use the wire filler in a small amount. However, the low α-ray filler is required only in the vicinity of the element, and the filler contained in the portion distant from the element may be a general-purpose filler.

In the present invention, encapsulation in which a large amount of general-purpose filler is used as the filler of the sealing resin composition that contacts the mold and a large amount of low α-ray filler is used as the filler that contacts the device. By forming a resin sheet for use and molding a package using this sheet, a resin-encapsulated semiconductor device does not malfunction, and a package with low cost can be obtained.

Considering the reaching distance of α rays, the thickness of the resin layer containing a large amount of low α ray filler is preferably 50 μm or more.

Further, the ratio of the resin portion in contact with the device to the total composition of the low α-ray filling material needs to be higher than the ratio of the resin portion of the outer peripheral portion of the package to the composition of the low α-ray filling material. The ratio of the portion in contact with is preferably 1.5 times or more the ratio of the outer peripheral portion, and is preferably 2 times or more in order to further improve the characteristics. Particularly, when it is 5 times or more, very good characteristics can be obtained.

D) The amount of the filler having a large particle size is increased in the resin composition in contact with the mold, and the amount of the filler having a small particle size is increased in the resin composition in contact with the device.

Generally, when the amount of the filler having a large particle diameter as the filler of the resin composition is increased, the resin strength is improved, so that package cracks can be reduced and burrs can be prevented from being generated in the gap between the molds. However, when the resin sheet is pressed against the element and pressed, if a filler with a large particle size is used, the bonding wire or inner lead may be deformed,
There is a problem in that the corners of the filling material are pierced by the element, which often causes defects. On the other hand, when a fine filler having a small particle diameter is used, deformation of the leads and damage to the element are small, but there is a problem that burrs are often generated.

In the present invention, the amount of the filler having a large particle diameter is large in the resin composition in contact with the mold, and the amount of the filler having a small particle diameter in the resin composition in contact with the element is large. By making a resin sheet and molding a package using this sheet, the strength is high, the occurrence of burrs is small,
Moreover, it is possible to obtain a package with less lead deformation and less damage to the device.

The thickness of the resin layer which is in contact with the mold side and which has a large filler having a large particle diameter is preferably 70 μm or more in order to maintain the strength of the package and prevent burrs. The thickness of the resin layer containing a large amount of material is preferably 30 μm or more in order to prevent deformation of the leads and wires.

The ratio of the filler having a large particle diameter in the resin portion on the outer peripheral portion of the package to the total composition must be larger than the ratio of the filler having a large particle diameter in the resin portion contacting the device to the entire composition. The ratio of the parts is preferably 1.5 times or more the ratio of the parts in contact with the element, and is preferably 2 times or more in order to further improve the characteristics. Particularly, when it is 5 times or more, very good characteristics can be obtained. Further, the ratio of the filler having a large particle diameter of the resin portion in contact with the element to the total composition must be larger than the proportion of the filler having a large particle diameter of the resin portion of the outer peripheral portion of the package to the total composition. The ratio of the contact portion is preferably 1.5 times or more of the ratio of the outer peripheral portion, and is preferably 2 times or more in order to further improve the characteristics. Particularly when it is 5 times or more, very good characteristics can be obtained.

The difference between the average particle size of the filler having a large particle size and the average particle size of the filler having a small particle size is preferably large.
It is desired to be 1.5 times or more, and in order to further improve the characteristics, it is preferably 3 times or more, and if 5 times or more, very good characteristics can be obtained.

(E) The amount of the fibrous filler in the resin composition in contact with the mold is increased, and the amount of the fibrous filler in the resin composition for sealing in contact with the device is decreased.

It has been generally known that the use of a fibrous filler in encapsulating a semiconductor package is very effective for increasing the strength. However, when the transfer molding method is used, the fibers may be caught at the gate. However, there is a problem that the bonding wire is washed away. Further, even in the method of pressure-bonding the sealing resin sheet, the use of the fibrous filler increases the resin viscosity, which causes a problem of wire deformation. Further, the material of the fibrous filler is generally glass fiber, and if sodium or the like contained in the glass melts out, there is a problem that the element is corroded and reliability is lowered.

In the present invention, the resin composition in contact with the mold has a large amount of the fibrous filler, and the sealing composition in contact with the device has a small amount of the fibrous filler, so that a general crushed resin is used. By making a sealing resin sheet containing a large amount of spherical or sub-spherical filler and molding the package using this sheet, a package with high strength and less lead deformation and damage to the element can be obtained. You can

The thickness of the resin layer containing a large amount of the fibrous filler in contact with the mold side is preferably 30 μm or more, and the thickness of the resin layer containing a small amount of the fibrous filler in contact with the element side is not included. It is preferably 30 μm or more.

(F) The amount of the non-moisture-permeable flaky filler is increased in the resin composition in contact with the mold, and the amount of general-purpose filler in the encapsulating resin composition in contact with the device is increased.

In order to secure the moisture resistance by using the usual filler for sealing the semiconductor package, it is necessary to increase the blending ratio of the filler, but by using the non-moisture permeable flaky filler, Even with this package, moisture permeation can be suppressed. Also, in the part that contacts the element,
Generally, the non-moisture-permeable flakes contain impurities, and there is a high possibility that the lead may be deformed due to its shape. Therefore, use of a general-purpose filler (spherical, subspherical, crushed, etc.) improves the filling property.

The present invention has been made on the basis of such knowledge, and the amount of the non-moisture-permeable flaky filler is large in the resin composition in contact with the mold, and the general-purpose filler is in the sealing resin composition in contact with the element. A resin sheet for encapsulation having a large amount of is prepared, and a package is formed using this sheet, whereby a package having high moisture resistance and high element reliability can be obtained.

The thickness of the resin layer containing a large amount of the non-moisture permeable flaky filler in contact with the mold side is preferably 30 μm or more, and a small amount or a non-moisture permeable flaky filler in contact with the element side is included. The thickness of the resin layer is preferably 30 μm or more.

Examples of the filler material that can be used in the above items a) to f) are quartz glass, fused silica, crystalline silica, glass, talc, alumina,
There are calcium silicate, calcium carbonate, barium sulfate, magnesia, silicon nitride, aluminum nitride, aluminum oxide, magnesium oxide, mica, metal, etc., and these are processed into crushed, unispherical, subspherical, and flaky shapes. be able to.

Of these, crushed filler, sub-spherical filler,
Most preferably, quartz glass or crystalline silica is used as the material for the spherical filler. It is most preferable to use glass as the material of the fibrous filler.

The filler used in the present invention preferably has a maximum particle size of 90% or less of the resin thickness on the element active surface side after the semiconductor element is sealed. If a resin having a particle diameter equal to or larger than the resin thickness is used, a force is applied to the semiconductor active surface and the wiring may be cut. Similarly, regarding the resin sheet on the back surface of the element, it is desirable that the maximum particle size is 90% or less of the resin thickness after sealing.

Next, it is flame retardant. The flame retardancy of the resin-encapsulated semiconductor device is an indispensable performance, and various flame retardants are used, but each has the following problems.

As a commonly used flame retardant, a halogen-containing resin such as a brominated epoxy resin is used as part of the encapsulating resin composition, and a heavy metal oxide such as antimony trioxide is used as part of the filler. May be used. Further, the surface of antimony trioxide is hydrophilic, and the sealing resin composition has a higher water absorption. Therefore, in the semiconductor device sealed with this resin composition, antimony is dissolved in hot water by being left at high temperature and absorbing moisture, and further, the halogen release due to the high temperature causes the aluminum wiring on the element to corrode and deteriorate, resulting in resin sealing. Type semiconductor device loses long-term reliability.

There are various phosphorus compounds as flame retardants.
Since the phosphorus compound is a harmful substance and imparts hygroscopicity to the resin composition, it has the same problem as described above. In addition, the metal oxide hydrate used as a flame retardant does not generate a harmful substance at the time of combustion, but contains moisture and hydroxide ions are generated, so that the aluminum wiring on the element is corroded and deteriorated, Reduce reliability. Therefore, there has been a problem that the reliability of the device is lowered while the flame retardancy is improved by increasing the amount of the flame retardant.

In the present invention, the concentration of the flame retardant contained in the encapsulating resin composition contacting the device is lower than the concentration of the flame retardant contained in the encapsulating resin composition forming the outside thereof, or the flame retardant is contained. It is characterized by not being.

The package molded by using such a resin sheet has a small amount of the flame retardant contained in the portion in contact with the inner element. Therefore, the element is not corroded and the reliability is improved. Further, since the outer peripheral portion of the package contains a large amount of flame retardant, the flame retardancy is equivalent to that of the conventional package. Further, since the amount of flame retardant as a whole is reduced, the amount of harmful gas generated during combustion is also reduced, and a good effect on the environment can be obtained.

The thickness of the layer containing a large amount of flame retardant is 5 to the resin thickness.
It is preferably 90%, and particularly preferably 50 to 90% in a package requiring flame retardancy.
Further, it is particularly preferably 5 to 50% in order to improve reliability. This is because it is necessary to increase the proportion of the layer containing the flame retardant of the resin sheet in order to increase the flame retardancy, but in order to reduce the reliability of the package and the amount of harmful gas generated, the flame retardant is used. This is because it is necessary to reduce the ratio of the layers that include it.

It is desirable that the amount of the flame retardant is larger in the portion in contact with the mold than in the portion in contact with the element. The proportion of the flame retardant in contact with the mold varies depending on the type,
For example, in the case of antimony trioxide which is an inorganic flame retardant, the range of 1 to 10% by weight is preferable. Since the metal hydroxide can be treated in the same manner as the filler, it is preferable to use 10 to 80% by weight instead of the filler. The halogen-based flame retardant is preferably used in an amount of 0.5 to 50% by weight, and particularly preferably 1 to 30% by weight for a brominated epoxy resin.

The ratio of the flame retardant to the total composition of the resin portion on the outer peripheral portion of the package must be larger than the ratio of the flame retardant to the total composition of the resin portion in contact with the device, and the ratio of the outer peripheral portion to the portion in contact with the device. The ratio is preferably 1.5 times or more, and particularly preferably 2 times or more in order to improve reliability and flame retardancy.

By using the encapsulating resin sheet as described above, the flame-retardant property is sufficiently maintained because the content of the flame-retardant agent in the resin in the outer peripheral portion of the package is high. Further, reliability is improved because the content ratio of the flame retardant in the portion in contact with the element is low,
Furthermore, since the amount of flame retardant used is reduced, adverse effects on the environment are reduced. As described above, according to the present invention, it is possible to obtain a resin-encapsulated semiconductor device having good reliability for a long period of time.

On the other hand, the amount of the curing accelerator contained in the encapsulating resin may be increased in order to increase the productivity of the resin-encapsulated semiconductor device manufacturing. However, since this curing accelerator generally has a low molecular weight, an increase in the amount thereof causes impurities in the encapsulating resin composition to corrode the element.
As a result, there is a problem that the amount of the curing accelerator increases and the reliability of the resin-encapsulated semiconductor device decreases.

Therefore, in the present invention, the concentration of the curing accelerator contained in the encapsulating resin composition in contact with the device is set lower than the concentration of the curing accelerator contained in the encapsulating resin composition forming the outside thereof.

Since the resin layer in the portion in contact with the mold has a large amount of the curing accelerator, it is cured in a short time and the mold can be opened immediately. Moreover, since the amount of the curing accelerator in the resin layer in contact with the element is small, there is little residual curing accelerator as an unreacted substance and the element is not corroded, so the reliability of the resin-encapsulated semiconductor device is improved. To do.

The thickness of the layer containing a large amount of the curing accelerator in contact with the mold is preferably 30 μm or more, and the thickness of the layer in contact with the device and containing a small amount of the curing accelerator is preferably 30 μm or more.

The concentration of the curing accelerator is expressed as a ratio (% by weight) to the organic resin component for encapsulation, and when the part in contact with the mold is p% by weight and the part in contact with the element is q% by weight,
006 <P <10, 0.005 <q <9,
And it is preferable that p> 1.1q. Further, it is preferable that p> 1.5q, which has a large difference between p and q, in order to improve the productivity and reliability of the resin-encapsulated semiconductor device, and in particular, p> 2.0q. preferable.

The amount of the curing accelerator is preferably 0.005 to 10% by weight, which is expressed as a ratio with respect to the organic resin component for sealing. If it is less than 0.005% by weight, the curing acceleration is insufficient, while if it exceeds 10% by weight, the unreacted curing accelerator floating in the interstices of the mesh of the epoxy resin corrodes the metal of the element or reduces the moisture resistance. Therefore, the reliability of the resin-encapsulated semiconductor device is reduced. In order not to reduce the reliability, the preferable range is 0.1 to 9% by weight, and the particularly preferable range is 0.2 to 8% by weight. Triphenylphosphine (TPP) is preferably added in an amount of 0.3 to 9% by weight, and heptadecylimidazole is preferably added in an amount of 0.2 to 7% by weight.

On the other hand, the mounting method currently applied may affect the reliability of the resin-sealed semiconductor device.
That is, in recent years, in order to efficiently mount a resin-sealed semiconductor device, an IR reflow method has been performed in which infrared rays are used to collectively melt solder to connect the resin-sealed semiconductor device and a substrate. There is. In this method, since the resin surface of the package other than the solder portion is also irradiated with infrared rays, moisture in the encapsulating resin composition heated by absorbing infrared rays is rapidly thermally expanded to cause resin cracks. There's a problem. In particular, in order to prevent malfunction due to light, it is essential to use a black colorant having a light-shielding property in the encapsulating resin composition, and this black colorant has a property of easily absorbing infrared rays. Therefore, in the black package that prevents malfunction due to light, resin cracks are likely to occur, and there is a problem that the reliability of the resin-sealed semiconductor device decreases.

Further, in order to identify the resin-encapsulated semiconductor device, conventionally, a thermosetting ink has been used to mark the package resin surface with a company name, a product name, a lot number and the like. However, this method has a problem in that, in addition to the complicated process, the imprinted character is rubbed and becomes difficult to see. For this reason, the surface layer of the resin of the semiconductor package is broken to a depth of several μm to several tens of μm by the energy of the laser beam to roughen the surface, and the marking is made by comparing the surface properties of the destroyed portion and the non-destructed portion. A marking method for visually recognizing has been put into practical use. However, the black package using the black colorant alone does not always provide a good contrast between the surface properties of the destructive portion and the non-destructive portion, and therefore the marking cannot be clearly seen.

It is the colorant that affects such properties.

In the present invention, it is desirable that the amount of the black colorant is larger in the part in contact with the device than in the part in contact with the mold, and the ratio of the black colorant in the layer in contact with the semiconductor device to the total composition is m (weight). %), And the ratio of the black colorant to the total composition of the layer in contact with the mold is n (wt%), 0.006 <m <10, 0 <n <9, m> 1.1n
Is desirably within the range. Further, it is better that the difference in the amount of the black colorant between the portion in contact with the mold and the portion in contact with the device is large, and it is preferable that m> 1.5n.
It is preferable that 1 <m <1, 0 <n <0.5, and m> 2n.

Increase the amount of black colorant on the side contacting the element,
The colorant on the side in contact with the mold preferably contains a color other than black or does not contain a colorant. A package formed using such a sheet contains a large amount of black colorant in the portion in contact with the inside element. Therefore, the light blocking effect is sufficient. Moreover, the appearance of the package becomes a color other than black, and it is easy to identify the package by coloring. Furthermore I
In order to improve the R reflow characteristics, it is preferable that the outer color is a color having a high reflectance, and in particular, a color close to white such as white or yellow, or a light color even if the color is present is preferable.

In order to improve the laser marking characteristics, it is necessary that the color of the resin in contact with the mold be different from that of the resin several μm below. The color of the resin in contact with the mold and the color of several μm below it are not particularly specified, but it is preferable to use a combination of those having the largest brightness and color difference. Further, in order to improve the light-shielding property, it is preferable to provide a part of the resin sheet containing a large amount of black colorant. The thickness of the layer in contact with the mold is required to be 1 to 200 μm, and 1 to 20 μm is preferable for a thin package. In particular, it is preferably about 1 to 5 μm in order to be suitable for laser marking.

Further, it is preferable to use a black organic dye as a colorant which makes it possible to clearly compare the surface properties of the destroyed portion and the non-destructed portion of the marking by laser. The marking characteristics of this black organic dye become remarkably clear when the amount is 0.1 to 1.0% by weight based on the weight of the previous weight. However, this dye may reduce the reliability of the device, and it is not preferable to include it in the layer in contact with the device. Therefore, it is preferable to use an inorganic pigment such as carbon black in the layer that is used as the resin on the outer peripheral portion of the package and is in contact with the element.

By changing the distribution of the colorant, the EPR
OM (erasable program read
It can be applied to encapsulation of only memory. EPR
The OM package needs a window for transmitting light such as UV to erase information written in the semiconductor device. Generally, the window portion and other portions are separately resin-sealed by a two-step molding method. But this method is very complicated. In this method, the window portion and other portions can be simultaneously sealed by using the resin sheet. Therefore, the EPROM can be sealed very easily. This method can be applied to other semiconductor packages having windows or the like.

The colorant used in the present invention may be any one as long as it causes the resin to develop a color, and a black pigment colorant is preferable as the light-shielding agent, and carbon black is particularly preferable. . Inorganic pigments, organic pigments, dyes and the like can be used as colorants of various colors. Inorganic pigments are generally not clear in color, but they are excellent in light resistance, heat resistance, solvent resistance, and have a great hiding power. Preferred inorganic pigments include ZnO, TiO ₂ , and 2PbCO as white pigments.
₃ · Pb (OH) ₂ , ZnS + BaSO _4, etc. as yellow pigments such as PbCrO ₄ , CdS + ZnO, K ₃ [Co
(NO ₂ ) ₆ ] as an orange pigment, and PbCrO ₄ +
PbSO ₄ + PbMoO ₄ or the like as a red pigment is used as Cd.
S + CdSe, Fe ₂ O ₃ , Pb ₃ O _4, etc. are used as blue pigments such as KFe [Fe (CN) ₆ ], NaFe [Fe
Examples include (CN) ₆ ] and NH ₄ Fe [Fe (CN) ₆ ] as green pigments such as CoO + ZnO and Cr ₂ O ₃ , and black pigments such as Fe ₃ O ₄ . In addition, extender pigments include calcium carbonate, barium sulfate, aluminum hydroxide, barite powder, aluminum powder, and bronze powder, and these pigments may be used alone or in combination of a plurality of pigments. Further, preferable organic pigments and dyes include azo-based, anthraquinone-based, and quinacridones as red and orange pigments, and triphenylmethane-based lakes, oxazine dyes, anthraquinone paints as purple pigments and dyes, and blue pigments and dyes. As, there are phthalocyanine pigments, indanthrone dyes, anthraquinone dyes, triphenylmethane-based lakes, green pigments include phthalocyanine-based, anthraquinone-based, black dyes, there is aniline oxidative condensate diamond black, these, The pigments and dyes may be used alone or in combination.

As the black organic dye used in the present invention, an azo-containing metal dye is particularly preferable. As the azo type dye, a monoazo type dye is suitable. Examples of the metal component contained in the monoazo dye include copper, potassium, sodium, chromium and cobalt.
Copper and chromium are particularly preferable. The metal content is preferably 0.01 to 20% by weight. Further, the melting point of the dye is preferably 100 ° C. or higher, and the decomposition temperature is preferably 200 ° C.

Since such colorants have different color-developing properties, the addition amount thereof varies, but it is preferably added within the range of 0.005 to 10% by weight based on the total composition. If it is less than 0.005% by weight, coloring is not sufficient. On the other hand, if it exceeds 10% by weight, the colorant floating in the interstices of the mesh of the epoxy resin corrodes the metal of the element or lowers the moisture resistance. Is to reduce. Therefore, the colorant is more preferably in the range of 0.05 to 5%, and particularly preferably in the range of 0.1 to 2% with respect to the organic resin component.

Examples of the laser used for marking the resin-sealed semiconductor device in the present invention include carbon dioxide gas laser, YAG laser, semiconductor laser and the like. The intensity of the irradiated laser is 0.05 to ² Joule · cm ² in terms of energy density, and
It is preferably 1 to 1 Joule · cm ² , and particularly preferably 0.2 to 0.5 Joule · cm ² .

By using the encapsulating resin sheet as described above, the temperature rise of the package during IR reflow is suppressed due to the high light reflectance of the resin in the portion in contact with the mold, and the humidity resistance reliability after reflow is improved. And the laser marking characteristics are improved due to the color difference between the surface layer and the layer thereunder. As described above, according to the present invention, it is possible to obtain a resin-encapsulated semiconductor device having good reliability for a long period of time.

The TAB (Tape) shown in FIG.
An Automated Bonding type package or a LOC (Lead on Chi) shown in FIG. 7B.
p) When molding a package for encapsulating both sides of a device, the resin thickness t ₁ on the device active surface side is due to the structure of the package.
And the resin thickness t ₂ on the back surface side may be different. In that case, if the conventional method is used, that is, if uniform resin is used, the package warps due to the difference in stress applied to the element due to the difference in resin thickness as the package becomes thinner, which makes mounting difficult and element cracking occurs. There is a problem that the reliability of the resin-encapsulated semiconductor device is deteriorated due to the occurrence of cracks, passivation cracks, disconnection of wiring, and the like.

As described above, in the double-sided sealing type package of the TAB type or LOC type element, the warp is likely to occur due to the difference in thickness between the upper and lower sides of the element. When the relationship between the warp amount and the characteristics of the resin-encapsulated semiconductor device was examined, it was found that the thermal shock resistance and the moisture resistance were significantly reduced when the warp amount exceeded 6%.
In the present invention, the warp amount (%) is the maximum package height measured by measuring the package thickness from the horizontal surface when the package thickness is L when the resin-encapsulated semiconductor device immediately after molding is allowed to stand on a horizontal plane. Is L ', {(L'-L) / L} x 1
The quantity indicated by 00. This relationship is shown in FIG. FIG.
In the figure, 16 indicates a horizontal plane and 17 indicates a resin-sealed semiconductor device.

In the present invention, a plurality of types of resin compositions having different thermal expansion coefficients and elastic moduli are sealed and the warpage amount is 6%.
It should be kept within. More specifically, in a resin-encapsulated semiconductor device, the thermal expansion coefficient of the encapsulating resin composition for encapsulating one surface of an element such as a semiconductor chip or a semiconductor module is a (1 / K), and the elastic modulus is b. (Pa), the resin thickness is c (mm), the thermal expansion coefficient of the sealing resin composition for sealing the other surface is d (1 / K), and the elastic modulus is e (Pa),
When the resin thickness is f (mm), 0.8 <(abc /
By encapsulating with the encapsulating resin composition having the property of def) <1.2, a resin-encapsulated semiconductor device with less warpage can be obtained. Here, the coefficient of thermal expansion, the elastic modulus, and the resin thickness of the encapsulating resin composition are the values after curing by molding.

The present invention is particularly effective for a resin-encapsulated semiconductor device in which the ratio of the upper and lower resin thicknesses after molding is 1.1 times or more, that is, c> 1.1f, and moreover, there is no warp. The effect of suppressing warpage is high in a resin-encapsulated semiconductor device in which the ratio of the vertical thickness is 1.2 times or more, which is likely to have a large influence, that is, c> 1.2f.

The relationship between the resin thickness after molding, the coefficient of thermal expansion and the elastic modulus in the present invention is ideally abc = def.
Is desired, but 0.8 <(abc / def)
Very effective in the range of <1.2, especially 0.
It is desired that 9 <(abc / def) <1.1.

According to the resin-encapsulated semiconductor device of the present invention, with the above-mentioned structure, the molding of the package is easy and the warpage is suppressed, and problems such as element cracks, passivation cracks, and disconnection of wiring occur. It is possible to obtain a resin-sealed semiconductor device that does not have resin. As the encapsulating resin composition for such a resin-encapsulated semiconductor device, the types of the above-mentioned resin and compounding agent can be appropriately combined and used.

As described above, various characteristics can be achieved by changing the type and concentration of the compounding agent, but it is preferable to adjust the amount within the range that satisfies the above formula.

In the present invention, other additives may be added to the encapsulating resin composition.

In addition to the above-mentioned inorganic filler, it is preferable to add a low stress additive such as rubber, elastomer or silicone gel in order to reduce the stress of the semiconductor encapsulating resin. The low stress additive preferably has a maximum particle size of 90% or less of the resin thickness on the element active surface side after element sealing.
If the particles having a particle diameter larger than the resin thickness are used, a force may be applied to the active surface of the semiconductor element and the wiring may be cut. Also,
Similarly, on the back surface of the element, it is desirable that the maximum particle size is 90% or less of the resin thickness after sealing.

Further, in the present invention, the above-mentioned uncured resin composition can be reinforced with various woven fabrics. When enumerating typical examples of the material of the woven fabric, there are glass, quartz, carbon fiber, silicon carbide, silicon nitride, aluminum nitride, alumina, zirconia, potassium titanate fiber in the inorganic type, and in the organic type, nylon type, acrylic type, Vinylon type, polyvinyl chloride type, polyester type, aramid type, phenol type, rayon type, acetate type, cotton, hemp, silk, wool and the like. These may be used alone or in combination.

A resin sheet for sealing which uses a prepreg reinforced with a woven cloth such as a glass woven cloth will be described below.
A curing agent, a catalyst, a filler, and other materials are dissolved in a solvent such as acetone to prepare a solution having an appropriate concentration, and this solution is applied to a woven cloth, or the woven cloth is impregnated in the solution and left standing. A prepreg can be prepared by volatilizing the solvent under heating or under reduced pressure.

Further, in the present invention, a sealing resin sheet obtained by laminating an uncured resin composition and a metal material or a high thermal conductivity ceramic material can be used. These materials are preferably metal foils having a thickness of 1000 μm or less or high thermal conductive ceramic plates. Further, when a sealing resin formed by stacking processed heat radiation plates made of a metal material or a ceramic material having high thermal conductivity is used, the heat dissipation of the resin-sealed semiconductor device is further improved. In this case, the sealing resin is arranged so that the uncured resin side of the sealing resin and the active surface side of the element face each other. As a material of the metal material, a material having high thermal conductivity is preferable. Examples of metals include iron, copper, aluminum, nickel, chromium, zinc, tin, silver, gold, lead, magnesium, titanium,
Examples thereof include alloys of these metals such as zirconia, tungsten, molybdenum, cobalt, stainless steel, 42 nickel-iron alloy, brass and duralumin.

Examples of the high thermal conductivity ceramics include alumina, aluminum nitride, silicon nitride, boron nitride, magnesia, crystalline silica and the like. However, if you want to make the package thinner, you can process it especially thin,
It is also desirable to use a lightweight material.

[0189]

EXAMPLES Examples of the present invention will be described in detail below. Reference Example 1 An example relating to the first resin-encapsulated semiconductor device of the present invention will be described.

The encapsulating resin sheets used in Examples 1 to 10 and Comparative Examples 1 to 4 were produced by the following method.

First, the raw materials for producing the sealing resin compositions 1 to 6 are shown below.

First epoxy resin: YX-4000H
(4,4'-bis (2,3-epoxypropoxy)-
3,3′-5,5′-tetramethylbiphenyl, manufactured by Yuka Shell Epoxy Co., epoxy equivalent 193, melting point 100
Second epoxy resin: Epicoat 1001 (bisphenol A type epoxy resin, manufactured by Yuka Shell Epoxy Co., epoxy equivalent 480, softening point 68 ° C) Third epoxy resin: Epicoat 807 (bisphenol F type epoxy resin, oilification Shell epoxy Co., Ltd., epoxy equivalent 170, viscosity 30Ps) Fourth epoxy resin: ESX-221 (Sumitomo Chemical Co., Ltd.,
Epoxy equivalent 220, softening point 85 ° C. Fifth epoxy resin: ESCN-195XL (Orthocresol novolac type epoxy resin, Sumitomo Chemical Co., Ltd., epoxy equivalent 197) First phenol resin: BRL-556 (Showa Polymer Co., Ltd.) , Phenol novolac resin, hydroxyl equivalent 104) Second phenol resin: XL-225L (manufactured by Mitsui Toatsu Chemicals, Inc., phenol aralkyl resin, softening point 84 ° C, hydroxyl equivalent 180) Silane coupling agent: A-187 (UCC) Carbon black: CB-30 (manufactured by Mitsubishi Kasei Co., Ltd.) Curing accelerator: C17Z (manufactured by Shikoku Kasei Co., heptadecyl imidazole) Silicone gel: heat curing type addition type silicone gel MBS resin: average particle size 30 μm Release agent: Carnauba wax Flame retardant aid: Antimony trioxide Filler (A): Melt Fused silica particles (spherical): Average particle size 8 μm (B): Fused silica particles (crushed): Average particle size 7 μm (C): Alumina particles (no acute angle): Average particle size 20 μm (D): Alumina particles (spherical) ): Average particle size 0.5 μm (E): Silicon nitride particles (crushed): Average particle size 3 μm (F): Aluminum nitride particles (without acute angle): Average particle size 20 μm, surface water resistant treatment (G): Boron nitride Particles (hexagonal plate shape): average particle size 0.8 μm.

Resin composition for sealing 1 using the above-mentioned raw materials
Nos. 6 to 6 were adjusted by the following method with the compounding ratio (parts by weight) shown in Table 1. The volume% of the filling material calculated from the density is shown in Table 1.

First, a phenol resin is heated and melted at a temperature above the softening point in a universal mixer to obtain a silicone gel and M
After adding BS resin powder, stir and mix, and further knead with a three-roll to disperse MBS resin powder uniformly,
Moreover, a premixed product having a reduced maximum particle size was prepared. Next, the filler was treated with a silane coupling agent in a Henschel mixer, and then the above-mentioned premixed product and other components such as epoxy resin were mixed and mixed therein. The obtained mixture was kneaded with two rolls at 60 to 110 ° C. to obtain a sealing resin composition.

The following evaluation test was performed on the obtained sealing resin composition. (1) Using a Koka type flow tester, melt viscosity at 175 ° C. was measured to evaluate fluidity. (2) A test piece was prepared by transfer molding at 175 ° C. for 3 minutes, and after-cured at 180 ° C. for 8 hours. The thermal expansion coefficient, flexural modulus, flexural strength, and thermal conductivity of these test pieces were measured. Table 1 shows the measurement results. The sealing resin compositions 1, 3 and 5 are resin compositions having excellent thermal conductivity, and the sealing resin compositions 2, 4 and 6 are resin compositions having excellent moldability.

[0196]

[Table 1] Examples 1 to 10 Encapsulating resin sheets were prepared using the encapsulating resin composition described above. First, the encapsulating resin composition is rolled to a predetermined thickness using a press to obtain one resin sheet. Next, two resin sheets are superposed on each other, heat-pressed with a press and rolled to a predetermined thickness to form one sealing resin sheet. Next, a cold blade was pressed against the heated sealing resin sheet to cut it into a predetermined size. Table 2 shows the sealing resin thicknesses and combinations used in each example.

[0197]

[Table 2] Next, using this sealing resin sheet, as shown in FIG.
A semiconductor package having the structure shown in (j) was produced. Example 1 to Example 4 and Example 9 are TAB method (chip size 5 mm
× 15mm × 200μm, Package size 8mm × 1
8 mm × 500 μm), Example 5 to Example 8 and Example 10 are wire bonding methods (chip size 15 mm × 15 m) for connecting with lead wires using a lead frame.
m × 450μm, package size 25mm × 25mm
× 3000 μm). The mold used was of the type shown in FIG.

The following evaluation test was performed on the moldability and the obtained resin-encapsulated semiconductor device. (1) For moldability, the presence or absence of voids and the releasability were visually judged.

In the table, "excellent" is a level at which there is no problem in void and releasability, and "good" is a void ratio of 1 to 5% (0.
(Ratio of packages with voids of 2 mm or more), which is not problematic for releasability, "Fair" has a void rate of 5 to 20%, and a flow mark is observed on the surface at the time of demolding, but it is shaped as a molded product. Indicates the level being achieved. In addition, "improper" molding means that a molded body cannot be formed. (2) In order to examine the heat dissipation property, the resin-encapsulated semiconductor device was operated and the steady temperature of the upper surface of the chip was measured. The heat generation amount of the semiconductor device in each example is 1W. (3) The following thermal cycle test (TCT test) was conducted to examine the thermal shock resistance. That is, the prepared package is -65 ° C to room temperature to 150 ° C for 30 minutes, 5 minutes, 30 minutes, respectively.
100 to 1000 cold and heat cycles with one minute as one cycle
The failure occurrence rate was checked by repeating the cycle and checking the operation characteristics of the device. (4) The following pressure cooker test (PCT) was performed in order to check the moisture resistance reliability. That is, after the produced package was left in a pressure cooker having a saturated steam pressure of 127 ° C. and 2.5 atm for 100 to 1000 hours, the incidence of defects (leakage defect, open defect) was examined. (5) The following experiment was conducted to examine the solder immersion resistance. That is, the produced package was left in an atmosphere of 85 ° C. and a relative humidity of 85% for 72 hours for moisture absorption, and then immersed in a solder bath at 240 ° C. for 30 seconds. At this point, the crack occurrence rate of the package was examined. further,
This solder dipping package 1 in the pressure cooker
100 to 1 in a saturated steam atmosphere at 27 ° C and 2.5 atm
After leaving it for 000 hours, the defect occurrence rate was examined. Note that the heat shock resistance, moisture resistance reliability and solder dipping resistance are shown in Test Sample 2
It is represented by the number of defectives relative to 0. The evaluation test results are shown in Table 3.

[0200]

[Table 3] Comparative Example 1 and Comparative Example 2 The same resin-encapsulated semiconductor device as in Example 1 was produced by a transfer molding method using one type of encapsulating resin composition. Table 4 shows the sealing resin composition used and molding conditions.
It shows in (1).

The moldability and the obtained resin-encapsulated semiconductor device were subjected to the same evaluation test as in Example 1. The evaluation test results are shown in Table 4 (2). Comparative Example 3 An encapsulating resin sheet was produced using one type of encapsulating resin composition, and the same resin encapsulating type semiconductor device as in Example 5 was used as Example 5 using this encapsulating resin sheet. It was made by the same method. Table 4 shows the sealing resin composition used and molding conditions.
It shows in (1).

The moldability and the obtained resin-encapsulated semiconductor device were subjected to the same evaluation test as in Example 1. The evaluation test results are shown in Table 4 (2). Comparative Example 4 The same resin-encapsulated semiconductor device as in Example 5 was produced by a transfer molding method using one type of encapsulating resin composition. Table 4 shows the sealing resin composition used and molding conditions.
It shows in (1).

The moldability and the obtained resin-encapsulated semiconductor device were subjected to the same evaluation test as in Example 5. The evaluation test results are shown in Table 4 (2).

[0204]

[Table 4] The resin-encapsulated semiconductor devices of Examples 1 to 10 shown in Table 3 are extremely excellent in heat dissipation properties as compared with the resin-encapsulated semiconductor devices of Comparative Example 1 to Comparative Example 4 shown in Table 4 (2). Cage,
It also shows excellent reliability in the thermal cycle test and pressure cooker test.

In particular, in the crack generation rate after solder immersion and the pressure cooker test, each example showed particularly excellent reliability as compared with each comparative example.

The first resin-encapsulated semiconductor device of the present invention is
Since at least one surface of the semiconductor element is sealed with a plurality of types of sealing resin compositions having different thermal conductivities, the adhesion between the semiconductor element and the sealing resin is good, and a package with extremely good thermal conductivity can be obtained. can get. Reference Example 2 An example relating to the second resin-encapsulated semiconductor device of the present invention will be described.

Examples 11 to 16 and Comparative Example 5
From the above, a sealing resin sheet used in Comparative Example 10 was produced by the following method.

First, the raw materials for producing the encapsulating resin compositions 7 to 14 are shown below.

First epoxy resin: YX-4000H
(4,4'-bis (2,3-epoxypropoxy)-
3,3′-5,5′-tetramethylbiphenyl, manufactured by Yuka Shell Epoxy Co., epoxy equivalent 193, melting point 100
C.) Second epoxy resin: ESX-221 (Sumitomo Chemical Co., Ltd.,
Epoxy equivalent 220, softening point 85 ° C. Third epoxy resin: ESCN-195XL (Orthocresol novolac type epoxy resin, Sumitomo Chemical Co., Ltd., epoxy equivalent 197) First phenol resin: BRG-556 (Showa Polymer Co., Ltd.) , Phenol novolac resin, hydroxyl equivalent 104) Second phenol resin: XL-225L (manufactured by Mitsui Toatsu Chemicals, Inc., phenol aralkyl resin, softening point 84 ° C, hydroxyl equivalent 180) Silane coupling agent: A-187 (UCC) Carbon black: CB-30 (manufactured by Mitsubishi Kasei Co., Ltd.) Curing accelerator: C17Z (manufactured by Shikoku Kasei Co., heptadecyl imidazole) Silicone gel: heat curing type addition type silicone gel MBS resin: average particle size 30 μm Release agent: Ester wax Flame retardant aid: Antimony trioxide Filler (A): Melt Fused silica particles: GR-80AK (maximum particle size 100 μm or more) (B): Fused silica particles: PK451 (maximum particle size 40
μm or less).

The above-mentioned raw materials were prepared in the compounding ratio (parts by weight) shown in Table 5 by the method of Reference Example 1 to prepare resin composition for sealing 7.
From 14.

About the obtained sealing resin composition 175
A test piece was prepared by transfer molding under the condition of 3 ° C. for 3 minutes, and after-cured at 180 ° C. for 8 hours. The thermal expansion coefficient and elastic modulus of these test pieces were measured. The measurement results are shown in Table 5.

[0212]

[Table 5] Examples 11 to 16 and Comparative Examples 5 to 1
0 An encapsulating resin sheet was produced using the encapsulating resin composition described above. First, the encapsulating resin composition is rolled to form an uncured resin sheet having a thickness of 50 to 400 μm.
Cut to 5 mm and 7 x 17 mm. Next 5 × 1
A resin sheet having a size of 5 mm was temporarily fixed to the active surface side of the semiconductor chip, and a resin sheet having a size of 7 × 17 mm was temporarily fixed to the back surface side of the semiconductor chip. Thereafter, these resin sheets were used in a combination as shown in Table 6 to seal semiconductor chips (chip size 5 mm × 15 mm × 200 μm) to obtain Examples 11 to 16 and Comparative Examples 5 to 10. Molding temperature is 180 ℃, molding time is 1 minute, 175 after molding
After-curing was performed at 8 ° C. for 8 hours. The package size is 8 mm × 18 mm × 380-450 μm.

[0213]

[Table 6] The following evaluation test was performed on the obtained resin-encapsulated semiconductor device. (1) Thermal cycle test (T
The CT test) and the pressure cooker test (PCT) for investigating the moisture resistance reliability were performed in the same manner as in Example 1. In addition, in the thermal cycle test, 50 to 500
A cycle repeat test was conducted. (2) The amount of warpage (%) immediately after molding was measured.

The evaluation test results are shown in Table 7.

[0215]

[Table 7] The amount of warpage is 1.67 to 5.22% in Examples 11 to 16.
In contrast, in Comparative Examples 5 to 10, 15.22.
It showed a very large value of ˜32.61%. In the thermal shock resistance test, the amount of warpage changes with temperature changes.
In Comparative Examples 5 to 10 in which the warpage was large, the element was repeatedly subjected to a force and a passivation crack was generated, and in Comparative Examples 9 and 10 in which the warpage exceeded 60 μm, the element was cracked. Further, in the moisture resistance test, in Comparative Examples 5 to 10 in which the amount of warpage was large, peeling occurred between the resin and the element, and moisture entered the package through the gap, resulting in a decrease in reliability.

The second resin-encapsulated semiconductor device of the present invention is
Since at least one surface of the element is made of a sealing resin composition having different thermal expansion coefficients and elastic moduli, and the warp amount of the resin-sealed semiconductor device is within 6%, the package does not warp, No element cracks, passivation cracks, wiring breaks, etc. As a result, the resin-encapsulated semiconductor device can be made sufficiently large and ultra thin. Reference Example 3 Hereinafter, Reference Examples 3, 4, 5 and 6 will be described as examples related to the third resin-sealed semiconductor device of the present invention.

Examples 17 to 22 and Comparative Example 1
The resin sheets for sealing used from 1 to Comparative Example 16 were produced by the following method.

First, the raw materials for producing the sealing resin compositions 15 to 22 are shown below.

First epoxy resin: YX-4000H
(4,4'-bis (2,3-epoxypropoxy)-
3,3′-5,5′-tetramethylbiphenyl, manufactured by Yuka Shell Epoxy Co., epoxy equivalent 193, melting point 100
C.) Second epoxy resin: ESX-221 (Sumitomo Chemical Co., Ltd.,
Epoxy equivalent 220, softening point 85 ° C) Third epoxy resin: ESCN-195XL (Orthocresol novolac type epoxy resin, Sumitomo Chemical Co., Ltd., epoxy equivalent 197) First phenol resin: BRL-556 (Showa High Polymer, Phenol novolak resin, hydroxyl equivalent 104) Second phenol resin: XL-225L (manufactured by Mitsui Toatsu Chemicals, Inc., phenol aralkyl resin, softening point 84 ° C, hydroxyl equivalent 180) Silane coupling agent: A-187 (UCC) ) Carbon black: CB-30 (manufactured by Mitsubishi Kasei) 1st curing accelerator: triphenylphosphine 2nd curing accelerator: C17Z (Shikoku Chemicals, heptadecyl imidazole) Silicone gel: heat curing type addition type silicone Gel MBS resin: average particle size 30 μm Release agent: Esterwak Flame retardant aid: antimony trioxide filler: molten silica particles: GR-80AK (maximum particle diameter 100μm or higher).

Resin materials for sealing 1 prepared by adjusting the above-mentioned raw materials in the proportions (parts by weight) shown in Table 8 by the method of Reference Example 1
5 to 22 were obtained.

About the obtained sealing resin composition 180
The gelation time was measured by the gelation test method on a hot plate at ℃. The measurement results are shown in Table 8.

[0222]

[Table 8] Examples 17 to 22 and Comparative Examples 11 to 16 Encapsulating resin sheets were produced using the encapsulating resin composition described above. First, the encapsulating resin composition is rolled to a predetermined thickness using a press to obtain one resin sheet. Next, two resin sheets in the combinations shown in Table 9 are superposed on each other, thermocompression-bonded by a press and rolled to a thickness of 200 μm to obtain one sealing resin sheet. Next, press a cold blade against the heated encapsulating resin sheet to form 5 × 15 mm and 7 × 1.
It was cut to a size of 7 mm.

Next, resin sheets for encapsulation were placed on the upper and lower sides of the TAB semiconductor chip (chip size 5 mm × 15 mm × 200 μm), and the package was formed by thermocompression bonding with a press die for 1 minute at 180 ° C. Aftercure was performed for 8 hours. The size of the produced package is 8 × 18
mm and the thickness is 500 μm.

The resin thickness above and below the element after sealing was 150 μm, and the thickness ratio of each resin layer was the same as before molding.

[0225]

[Table 9] In Examples 17 to 22, the amount of the curing accelerator on the die side is larger than that on the element side. On the other hand, in Comparative Examples 11 to 15, the amount of the curing accelerator is uniform in the resin sheet, and in Comparative Example 16, the element side is larger than the mold side.

The following evaluation test was performed on the obtained resin-encapsulated semiconductor device. (1) Thermal cycle test (T
The CT test), the pressure cooker test (PCT) for investigating the moisture resistance reliability, and the solder dipping resistance test were performed in the same manner as in Example 1. In the cooling / heating cycle test, 50 to 500 cycles were repeated. (2) The appearance immediately after molding was visually judged. A resin-encapsulated semiconductor device immediately after molding, in which voids and unfilled portions were found, was regarded as a defective product, and was represented by the number of 20 test samples.

The evaluation test results are shown in Table 10.

[0228]

[Table 10] Compared to Comparative Examples 11 to 16, the resin-encapsulated semiconductor devices of Examples 17 to 22 are excellent in the thermal shock resistance test and the moisture resistance test, and in particular, the crack occurrence rate after solder immersion is small and the resin of the Comparative Example is small. The reliability is improved as compared with the sealed semiconductor device. Also, the appearance immediately after molding was excellent.

The third resin-encapsulated semiconductor device of the present invention is
Since the concentration of the curing accelerator of the encapsulating resin composition for encapsulating at least one surface of the element is different between the inside and the outside of the package, the reliability of a large and ultra-thin resin-encapsulated semiconductor device is improved. be able to. That is, since the concentration of the curing accelerator contained in the encapsulating resin composition in contact with the element is lower than the concentration of the curing accelerator contained in the encapsulating resin composition forming the outside, encapsulation of the surface in contact with the mold The resin composition for use is cured quickly, and the element is not corroded by the unreacted curing accelerator. As a result, the reliability of the device is good,
Moreover, it is possible to obtain a resin-encapsulated semiconductor device having extremely good productivity. Reference Example 4 Encapsulating resin sheets used in Examples 23 to 37 and Comparative Examples 17 to 24 were produced by the following method.

First, the raw materials for producing the sealing resin compositions 23 to 32 are shown below.

Epoxy resin: ESX-221 (Sumitomo Chemical Co., Ltd., epoxy equivalent 220, softening point 85 ° C.) Flame-retardant epoxy resin: AER-745 (Asahi Kasei Co., brominated epoxy resin) Phenolic resin: XL-225L ( Mitsui Toatsu Chemicals, phenol aralkyl resin, softening point 84 ° C, hydroxyl equivalent 1
80) Silane coupling agent: A-187 (manufactured by UCC) Carbon black: CB-30 (manufactured by Mitsubishi Kasei) Curing accelerator: C17Z (manufactured by Shikoku Kasei, heptadecyl imidazole) Silicone gel: heat curing type addition type Silicone gel MBS resin: Average particle size 30 μm Release agent: Ester wax Flame retardant: Antimony trioxide Flame retardant: Ammonium phosphate Flame retardant: Aluminum hydroxide Fused silica: GR-80AK.

[0232] The above-mentioned raw materials were prepared in the blending ratio (parts by weight) shown in Table 11 by the method of Reference Example 1 to prepare resin composition 2 for sealing.
3 to 32 were obtained. The composition ratio of the uncured resin composition is shown in Table 1.
It is shown in FIG.

[0233]

[Table 11] Example 23 to Example 32 and Comparative Example 17 to Comparative Example 22 Encapsulating resin sheets were produced using the encapsulating resin composition described above. First, the encapsulating resin composition is rolled to a predetermined thickness using a press to obtain one resin sheet. Next, the resin sheets are stacked in the combinations shown in Table 12 to form 1
Heat press-bond the sheet that became 200 μm with a press, 60
Roll to a thickness of 0 μm to form a single resin sheet for sealing. At this time, composition mixing occurs between the melted sheets as shown in FIG. Next, press a cold blade against the heated resin sheet for sealing to obtain 5 × 15 mm and 7 ×
It was cut to a size of 17 mm.

[0234]

[Table 12] Next, TAB semiconductor chip (5 mm × 15 mm × 400
μm) and the resin sheets for encapsulation are arranged by the combination of the sheets shown in Table 13, and the package is formed by thermocompression bonding with a press die for 1 minute at 175 ° C., and after-curing at 180 ° C. for 8 hours. Examples 23-32 and Comparative Example 1
7-22 were obtained. The size of the created package is 8 × 1
The thickness is 8 mm and the thickness is 1350 μm. The upper and lower resin thicknesses of the element after sealing were 475 μm, respectively, and the thickness ratio of each resin layer was the same as before molding.

[0235]

[Table 13] In Examples 23 to 26, the amount of the flame retardant on the surface side of the resin on the semiconductor element active surface side was larger than the amount of the flame retardant on the inner side, and the amount of the flame retardant on the surface side of the resin on the back side of the semiconductor element and the inside The amount of flame retardant is the same.

In Examples 27 to 32, the amount of the flame retardant on the surface side of the resin on the active surface side of the semiconductor element is larger than the amount of the flame retardant on the inside, and the amount of the flame retardant on the surface of the resin on the back side of the semiconductor element is Greater than the amount of flame retardant inside.

In Comparative Example 17, no flame retardant was included.

In Comparative Examples 18 to 22, the amount of flame retardant was constant in both the upper and lower resins of the semiconductor element.

The following evaluation test was performed on the obtained resin-encapsulated semiconductor device. (1) Thermal cycle test (T
The CT test) and the pressure cooker test (PCT) for investigating the moisture resistance reliability were performed in the same manner as in Example 1. (2) Moisture resistance test after IR reflow The manufactured package was left in an atmosphere of 85 ° C. and a relative temperature of 85% for 72 hours for moisture absorption, and then irradiated with infrared rays and heated at 240 ° C. for 30 seconds. did. At this point, the crack occurrence rate of the package was examined. Furthermore, this package is set to 2.5 atmospheres 127 in a pressure cooker.
After leaving it in a saturated steam atmosphere at a temperature of 100 ° C. for 100 to 1000 hours, the defect occurrence rate was examined by checking the operation characteristics of the device. (3) Flame-retardant test Standard UL9 in the package in which each semiconductor device is sealed.
Flame retardancy was evaluated according to 4 (USA). The evaluation test results are shown in Table 14.

[0240]

[Table 14] From Table 14, the resin-sealed semiconductor devices of Examples 23 to 32 have very good reliability in the thermal cycle test, the humidity resistance reliability test, and the humidity resistance reliability test after IR reflow.
Also, a very good value was obtained for flame retardancy. However, the resin-sealed semiconductor devices of Comparative Examples 18 to 22 were not reliable. Further, Comparative Example 17 having the same reliability as that of the example did not have sufficient flame retardancy. Example 33 to Example 37 and Comparative Example 23 to Comparative Example 24 Combining the compositions shown in Table 12, a sheet containing no flame retardant was superposed only on the part that is above the element, and the size is 7 mm.
A resin sheet having a size of × 17 mm × 600 μm was prepared by the method shown in FIG. This was heated at 180 ° C. for 5 hours and cured to obtain a resin sheet.

In the example, two same resin sheets are laminated so as to surround the layer not containing the flame retardant-containing layer. In Comparative Example 23, two resin sheets containing no flame retardant were stuck together. In Comparative Example 24, two resin sheets uniformly containing the flame retardant were stuck together.

Using this resin sheet, a flame retardance test (Hot Wire Ignition test) of the resin sheet was carried out by the following method.

As shown in FIG. 17, a resistance wire (B & S gauge No. 24 resistance wire, not containing iron, 20% chromium, 80% nickel, diameter 0.02) was set around the cured resin sheet 23.
01 ″, 161Ω / ft, 865ft / 1b) 24 to 1
It is wound 5 times at / 4 ″ intervals. 65 W is generated on the resistance wire 24 and the number of seconds until ignition is measured. The flame retardancy test results of the resin sheet are shown in Table 15.

[0244]

[Table 15] As shown in Table 15, the sheet of Comparative Example 23 containing no flame retardant has very low flame retardancy, while Example 33 does not.
The sheets having a grading flame retardant concentration of ˜37 showed excellent flame retardancy equivalent to that of the single composition sheet containing the flame retardant of Comparative Example 24.

The fourth resin-encapsulated semiconductor device of the present invention is
Since the concentration of the encapsulating resin composition for encapsulating at least one surface of the element is different between the inside and the outside of the package, the reliability of the large-sized and ultra-thin resin-encapsulated semiconductor device can be improved. That is, since the concentration of the flame retardant is lower than the concentration of the flame retardant contained in the encapsulating resin composition forming the outside, the reliability of the semiconductor element is good, and a relatively small amount of flame retardant is sufficient for flame retardance. A resin-encapsulated semiconductor device having properties can be obtained. Reference Example 5 Sealing resin sheets used in Examples 38 to 49 and Comparative Examples 25 to 36 were produced by the following method.

First, the raw materials for producing the sealing resin compositions 33 to 40 are shown below.

Epoxy resin: ESX-221 (Sumitomo Chemical Co., Ltd., epoxy equivalent 220, softening point 85 ° C.) Flame-retardant epoxy resin: AER-745 (Asahi Kasei Co., brominated epoxy resin) Phenolic resin: XL-225L ( Mitsui Toatsu Chemicals, phenol aralkyl resin, softening point 84 ° C, hydroxyl equivalent 1
80) Silane coupling agent: A-187 (manufactured by UCC) Carbon black: CB-30 (manufactured by Mitsubishi Kasei) Curing accelerator: C17Z (manufactured by Shikoku Kasei, heptadecyl imidazole) Silicone gel: heat curing type addition type Silicone gel MBS resin: Average particle size 30 μm Release agent: Ester wax Flame retardant: Antimony trioxide Filler; Shattered silica: GR-80T (manufactured by Toshiba Ceramics Co., average particle size 22 μm) Filler; Shattered silica: SGA (Toshiba Ceramics Co., average particle size 5 μm) Filler; crushed silica: USS-80 (Toshiba Ceramics, average particle size 20 μm, low α-ray filler) Filler; crushed silica: USG-5A ( Toshiba Ceramics Co., Ltd., average particle diameter 10 μm, filler for low α rays) Filler; Spherical silica: FB-5S (electrochemical work) Company Ltd., average particle size 6 [mu] m) filler; glass fiber: REVX2008 (mean diameter 1
0 μm, average length 60 μm) Filler; non-moisture permeable thin film: laminated mica flakes.

The above-mentioned raw materials were adjusted in the mixing ratio (parts by weight) shown in Table 16 by the method of Reference Example 1 to prepare resin composition 3 for sealing.
3 to 40 were obtained. The composition ratio of the uncured resin composition is shown in Table 1.
6 is shown.

[0249]

[Table 16] Examples 38 to 49 and Comparative Examples 25 to 36

An encapsulating resin sheet was prepared using the encapsulating resin composition described above. First, the encapsulating resin composition is rolled to a predetermined thickness using a press to obtain one resin sheet.
Next, the resin sheets were laminated in the combinations shown in Table 17, and the sheets having a thickness of 400 μm were heated and pressure-bonded by a press and rolled to a thickness of 300 μm to obtain one sealing resin sheet. At this time, composition mixing occurs between the melted sheets as shown in FIG. Next, press the cold blade against the heated sealing resin sheet and press it to 5 x 15 mm.
And cut into a size of 7 × 17 mm. In addition, as a comparative example, a resin composition for encapsulation was used alone, and a thickness of
The resin sheet of was produced.

[0251]

[Table 17] Next, TAB semiconductor chip (5 mm × 15 mm × 400
μm) and the encapsulating resin sheets are arranged by the combination of the sheets shown in Table 18 above and below, and the package is molded by thermocompression bonding with a press die for 1 minute at 175 ° C. and after-cured at 180 ° C. for 8 hours. Examples 38 to 49 and Comparative Example 2
5 to 36 were obtained. The size of the created package is 8 × 1
The thickness is 8 mm and the thickness is 900 μm. The resin thickness above and below the element after sealing was 250 μm, and the thickness ratio of each resin layer was the same as before molding.

[0252]

[Table 18] Example 38 is different from Comparative Example 25 in that the amount of filler in the vicinity of the upper and lower portions of the semiconductor element is smaller. Further Example 38
Differs from Comparative Example 26 in that the amount of filler on the surface is large.

Example 39 differs from Comparative Example 25 in that the amount of filler in the vicinity of the active surface of the semiconductor element is small. Further, Example 39 differs from Comparative Example 26 in that the amount of filler on the surface is large. In Example 47, it was in a crushed state, and in Comparative Example 3
No. 3 is fibrous. Differ in some respects.

Example 40 is different from Comparative Example 27 in the kind of filler in the vicinity of the upper and lower sides of the semiconductor element. Example 40 has a spherical shape, and Comparative Example 27 has a crushed shape.

Further, Example 40 is different from Comparative Example 28 in the kind of the filler on the surface. In Example 40, it is crushed, and in Comparative Example 28, it is spherical.

Example 41 differs from Comparative Example 27 in the kind of filler in the vicinity of the active surface of the semiconductor element. Example 4
No. 1 is spherical, and Comparative Example 27 is crushed.

Further, Example 41 is different from Comparative Example 28 in the kind of surface filler. In Example 41, it is crushed, and in Comparative Example 28, it is spherical.

Example 42 is different from Comparative Example 29 in the kind of filler in the upper and lower neighborhoods of the semiconductor element. Example 42
Is a low α-ray type, and Comparative Example 29 is a general-purpose type.

Further, Example 42 is different from Comparative Example 30 in the kind of the filler on the surface. The example 42 is a general-purpose type, and the comparative example 30 is a low α-ray type.

Example 43 is different from Comparative Example 29 in the kind of the filler near the active surface of the semiconductor element. Example 4
3 is a low α-ray type, and Comparative Example 29 is a general-purpose type. Further, Example 43 is different from Comparative Example 30 in the kind of the filler on the surface. Example 43 is a general-purpose type, and Comparative Example 30 is a low α-ray type.

Example 44 differs from Comparative Example 31 in that the size of the filler in the vicinity of the top and bottom of the semiconductor element is smaller.
Further, Example 44 is different from Comparative Example 32 in that the size of the filler on the surface is larger.

Example 45 differs from Comparative Example 31 in that the size of the filler in the vicinity of the active surface of the semiconductor element is smaller. Further, Example 45 is different from Comparative Example 32 in that the size of the filler on the surface is larger.

Example 46 is different from Comparative Example 33 in the kind of filler in the vicinity of the upper and lower sides of the semiconductor element. In Example 46, it was crushed, and in Comparative Example 33, it was fibrous.

Further, Example 46 is different from Comparative Example 34 in the kind of the filler on the surface. In Example 46, it was fibrous, and in Comparative Example 34, it was crushed.

Example 47 differs from Comparative Example 33 in the kind of filler in the vicinity of the active surface of the semiconductor element. Example 4
7 is crushed, and Comparative Example 33 is fibrous.

Further, Example 47 is different from Comparative Example 34 in the kind of the filler on the surface. In Example 47, it was fibrous, and in Comparative Example 34, it was crushed.

Example 48 is different from Comparative Example 35 in the kind of the filler in the vicinity of the upper and lower sides of the semiconductor element. In Example 48, it is in a crushed state, and in Comparative Example 35, it is a moisture impermeable thin film.

Further, Example 48 is different from Comparative Example 36 in the kind of surface filler. In Example 48, it is a non-moisture permeable thin film, and in Comparative Example 36, it is crushed.

Example 49 differs from Comparative Example 35 in the kind of filler in the vicinity of the active surface of the semiconductor element. Example 4
No. 9 is crushed, and Comparative Example 35 is a non-moisture permeable thin film.

Further, Example 49 differs from Comparative Example 36 in the kind of surface filler. In Example 49, it is a non-moisture permeable thin film, and in Comparative Example 36, it is crushed.

The following evaluation test was performed on the obtained resin-encapsulated semiconductor device. (1) Thermal cycle test (T
The CT test) and the pressure cooker test (PCT) for investigating the moisture resistance reliability were performed in the same manner as in Example 1. In addition, the moisture resistance test after IR reflow was performed in Example 23.
The same conditions were used. However, in order to clarify the difference in effect between the example and the comparative example, 500 in the TCT test.
After repeating ~ 5000 cycles, the PCT test and I
Moisture resistance test after R reflow, 500-5000
After leaving for a time, the defect occurrence rate was examined. (2) Examination of Burr Length When molding a semiconductor device, there is a possibility that burrs may appear between the outer die and the inner die, and the clearance between the outer die and the inner die is set to 8 μm. A mold and a mold having a size of 15 μm were prepared, and the length of the burr generated in the gap after molding was measured. (3) Memory operation test 4 MDRA that may cause malfunctions due to radiation
An operation test was carried out on a package formed using the M element. The evaluation test results are shown in Tables 19 to 22.

[0272]

[Table 19]

[0273]

[Table 20]

[0274]

[Table 21]

[0275]

[Table 22] Hereinafter, the effects of the present invention will be described with reference to Examples and Comparative Examples having the same resin composition. (1) Examples 38 and 39 In Comparative Example 25, since the filler was extremely highly filled, the chips were damaged a lot, and Tables 19 and 2
As shown in 0, the reliability is lower than in Examples 38 and 39. In addition, Comparative Example 26 has Examples 38 and 3
Compared with No. 9, since the amount of the filler in the outer peripheral portion of the package was small, the water absorption was large, and the result of the moisture resistance reliability test was low. (2) Examples 40 and 41 In Comparative Example 27, since all the crushed fillers were used, the chips were damaged a lot, and as shown in Table 20, the reliability was higher than that of Examples 40 and 41. It is slightly lower. Further, in Comparative Example 28, since the filler in the outer peripheral portion of the package is spherical, the strength is lowered and the result of the moisture resistance reliability test is lowered as compared with Examples 40 and 41. Further, as shown in Table 21, the occurrence of burrs increases. (3) Examples 42 and 43 Comparative Examples 29 and 30 and Examples 42 and 43 were almost the same in the reliability test results, but as shown in Table 22, Comparative Example 29 failed in the memory operation test. Further, Comparative Example 30 uses a large amount of expensive low α-ray filler as compared with Examples 42 and 43. (4) Examples 44 and 45 In Comparative Example 31, since the filler has a large particle diameter, a large amount of damage is caused to the chip, and as shown in Table 20, the reliability is lower than that of Examples 44 and 45. are doing. Further, in Comparative Example 32, the strength of the package is weakened and the result of reliability is lowered because the fine filler is used as compared with Examples 44 and 45. Furthermore, since the particle diameter of the filler in the outer peripheral portion of the package is small, as shown in Table 21, the occurrence of burrs increases. (5) Examples 46 and 47 In Comparative Example 33, the glass fiber is closer to the device as compared with Examples 46 and 47, and the reliability is significantly lowered due to the generation of impurities. Further, in Comparative Example 34, as compared with Examples 46 and 47, since the outer peripheral portion of the package does not have glass fibers, the strength of the package as a whole is lowered. (6) Examples 48 and 49 In Comparative Example 35, a thin piece is closer to the element than Examples 48 and 49, and reliability is lowered due to generation of impurities and damage to lead wires. Further, in Comparative Example 36, as compared with Examples 48 and 49, since there is no thin piece on the outer peripheral portion of the package, it is easy to absorb moisture and the reliability is lowered.

The fifth resin-encapsulated semiconductor device of the present invention is
Since the type and amount of the filler contained in the encapsulating resin composition for encapsulating at least one surface of the element are changed, various characteristics such as package strength, moisture resistance, reliability, and burr characteristics can be easily improved. Can be made. Further, the production cost of the resin-encapsulated semiconductor device can be reduced. Reference Example 6 The encapsulating resin sheets used in Examples 50 to 58 and Comparative Examples 37 to 42 were produced by the following method.

First, the raw materials for producing the sealing resin compositions 41 to 50 are shown below.

First epoxy resin: YX-4000H
(4,4'-bis (2,3-epoxypropoxy)-
3,3 ', 5,5'-Tetramethylbiphenyl, made of oiled shell epoxy, epoxy equivalent 193, melting point 100 ° C) Second epoxy resin: ESX-221 (Sumitomo Chemical, epoxy equivalent 220, softening point 85 ° C) ) Third epoxy resin: GY-260 (bisphenol A
Type epoxy resin, manufactured by Ciba Geigy) Fourth epoxy resin: ESCN-195XL (Orthocresol novolac type epoxy resin, Sumitomo Chemical, epoxy equivalent 197) Fifth epoxy resin: triglycidyl isocyanurate First phenol resin: BRG -556 (Showa High Polymer, phenol novolac resin, hydroxyl equivalent 104) 2nd phenol resin: XL-225L (Mitsui Toatsu Chemicals, phenol aralkyl resin, softening point 84 ° C, hydroxyl equivalent 180) Acid anhydride: THPA silane coupling agent: a-187 (UCC Co.) first colorant: carbon black (CB-30) a second colorant: titanium oxide (TiO ₂₎ third colorant: azo type black organic dyes ( OIL BLAC
K BY Ciba Geigy) Fourth colorant: Cadmium yellow (CdS + Zn)
S) Fifth colorant: red iron oxide (Fe ₂ O ₃ ) Sixth colorant: potassium ferrocyanide K ₄ Fe [Fe
(CN) ₆ ] Seventh colorant: Cobalt green (CoO + ZnO) Curing accelerator: C17Z (Heptadecyl imidazole manufactured by Shikoku Kasei) Silicone gel: Heat curing type addition type silicone gel MBS resin: Average particle size 30 μm Release agent : Ester wax Flame retardant: Antimony trioxide Fused silica: GR-80AK.

The above-mentioned raw materials were prepared in the blending ratio (parts by weight) shown in Table 23 by the method of Reference Example 1 to prepare resin composition 4 for sealing.
1 to 50 was obtained. Table 2 shows the composition ratio of the uncured resin composition.
3 shows.

[0280]

[Table 23] Example 50 to Example 58 and Comparative Example 37 to Comparative Example 42 A sealing resin sheet was produced using the above sealing resin composition. First, the encapsulating resin composition is rolled to a predetermined thickness using a press to obtain one resin sheet. Next, the resin sheets are stacked in the combinations shown in Table 24 and 4
The sheet with the size of 00μm is heated and pressed with a press,
Roll to a thickness of μm to form a single sealing resin sheet. At this time, composition mixing occurs between the melted sheets as shown in FIG. Next, press a cold blade against the heated resin sheet for sealing to obtain 5 × 15 mm and 7 ×
It was cut to a size of 17 mm.

[0281]

[Table 24] Next, TAB semiconductor chip (5 mm × 15 mm × 200
μm) above and below the encapsulating resin sheet with the combination of the sheets shown in Table 25, and thermocompression bonding with a press die for 1 minute at 175 ° C. to form a package, and after curing at 180 ° C. for 8 hours. Examples 50-58 and Comparative Example 3
7-42 were obtained. The size of the created package is 8 × 1
The thickness is 8 mm and the thickness is 450 μm.

[0282]

[Table 25] Example 50 differs from Comparative Example 37 in the coloring agent on the outer surface. Example 50 is white, whereas Comparative Example 37
Then it is black. Further, Example 50 is different from Comparative Example 38 in the colorant near the element surface. In Example 50, it is black, whereas in Comparative Example 38, it is white.

Further, Examples 54 to 58 are Comparative Examples 39 to 4
Compared with No. 2, the coloring agent near the surface of the device is different. Example 54
In contrast, in Comparative Examples 39 to 42, the colors are yellow, red, blue, and green, respectively.

Example 54 differs from Comparative Example 37 in the coloring agent on the outer surface. In Example 54, the azo black organic dye was used, whereas in Comparative Example 37, the carbon black was used. Example 51 has a thinner white resin layer than Example 50. Further, Example 52 has a thinner white resin layer than Example 51, and the white resin layer of Example 53 is even thinner.

The following evaluation test was conducted on the obtained resin-encapsulated semiconductor device. (1) The moisture resistance test after IR reflow was performed by the same method as in Example 23. (2) Semiconductor device operation test In order to examine the light transmittance, a semiconductor device operation test was conducted while irradiating visible light from the active surface side of the semiconductor element. (3) Laser Marking Contrast A semiconductor device was irradiated with a carbon dioxide gas laser (energy density maximum 0.5 Joule / cm ² ) for 1 / 500,000 seconds through a predetermined mask for marking. The results of visually observing the contrast of the resulting markings were classified into three levels, and the color difference was measured.

Regarding the evaluation results, Table 26 shows the humidity resistance test after IR reflow, and Table 27 shows the semiconductor device operation test.
Table 28 shows the laser marking contrasts.

[0287]

[Table 26]

[0288]

[Table 27]

[0289]

[Table 28] From Table 26, the resin-encapsulated semiconductor devices of Examples 50 to 53, Example 55, and Example 58 have extremely good reliability in the moisture resistance test after IR reflow, as compared with Comparative Examples 37 and 41. The results were obtained.

Further, as shown in Table 27, the results of Examples 50-
No. 58 did not malfunction in the semiconductor device operation test because it contained the black light-shielding colorant, but Comparative Examples 38 to 42 malfunctioned because they did not contain the black light-shielding colorant.

From Table 28 showing the results of laser marking, Example 50 in which the colorant concentration was inclined was obtained.
In Comparative Examples 37 to 42, the contrast and the color difference were large, while in Comparative Examples 37 to 42 using the monochromatic resin, the contrast and the color difference were small.

As described above, regarding the colorant, at least one selected from the concentration and type of the colorant contained in each encapsulating resin composition is changed, so that good reliability after IR reflow is obtained. It is obtained and the laser marking property is improved. Reference Example 7 Curing accelerators, flame retardants, fillers with different types and blending ratios,
To investigate the effect of combining colorants, Example 5
The resin sheets for encapsulation used in Examples 9 to 65 and Comparative Example 43 were prepared by the following method.

First, the raw materials for producing the encapsulating resin compositions 51 to 65 are shown below.

Epoxy resin: ESX-221 (Sumitomo Chemical Co., Ltd., epoxy equivalent 220, softening point 85 ° C.) Flame-retardant epoxy resin: AER-745 (Asahi Kasei Co., brominated epoxy resin) Phenolic resin: XL-225L ( Mitsui Toatsu Chemicals, phenol aralkyl resin, softening point 84 ° C, hydroxyl equivalent 1
80) Silane coupling agent: A-187 (manufactured by UCC) Colorant: carbon black CB-30 (manufactured by Mitsubishi Kasei) Colorant: titanium oxide Curing accelerator: C17Z (manufactured by Shikoku Kasei, heptadecyl imidazole) Silicone Gel: Heat curing type addition type silicone gel MBS resin: Average particle size 30 μm Release agent: Ester wax Flame retardant: Antimony trioxide Crushed silica: GR-80T (manufactured by Toshiba Ceramics Co., Ltd.,
Average particle diameter 22 μm).

The encapsulating resin composition 5 was prepared by adjusting the above-mentioned raw materials in the proportions (parts by weight) shown in Table 29 by the method of Reference Example 1.
1 to 65 were obtained. Table 2 shows the composition ratio of the uncured resin composition.
9 shows.

[0296]

[Table 29] Examples 59 to 65 and Comparative Example 43 Encapsulating resin sheets were prepared using the encapsulating resin composition described above. The uncured resin composition is 200 μm using a press
To the thickness of. The resin sheets are combined in a combination as shown in Table 30, and the sheets having a thickness of 400 μm are heat-pressed by a press and rolled to a thickness of 200 μm to form one sealing resin sheet. Next, press a cold blade against the heated resin sheet for sealing to obtain 5 × 15 mm and 7
It was cut into a size of × 17 mm.

[0297]

[Table 30] Therefore, TAB semiconductor chip (5 mm × 15 mm × 200
μm) above and below the encapsulating resin sheet with the combination of the sheets shown in Table 31, and thermocompression bonding with a press die for 1 minute at 175 ° C. to form a package, and after curing at 180 ° C. for 8 hours. , Examples 50 to 58 and Comparative Examples 37 to 42 shown in Table 31 were obtained. The prepared package has a size of 8 × 18 mm and a thickness of 450 μm. The resin thickness above and below the element after sealing is 125 μm,
Furthermore, the thickness ratio of each resin layer was the same as before molding.

[0298]

[Table 31] In Example 59, the resin layer on the mold side contains more curing accelerator and flame retardant than the resin layer on the element side.

In Example 60, the resin layer on the mold side contains more curing accelerator and inorganic filler than the resin layer on the element side.

In Example 61, the flame retardant and the inorganic filler are more contained in the resin layer on the mold side than on the resin layer on the element side.

In Example 62, the resin layer on the die side contained more curing accelerator than the resin layer on the element side, and the resin layer on the element side contained a black colorant, and the resin layer on the die side was formed. Contains a white colorant.

In Example 63, the resin layer on the die side contained more flame retardant than the resin layer on the element side, and the resin layer on the element side contained a black colorant, and the resin layer on the die side Contains a white colorant.

In Example 64, the resin layer on the die side contained more inorganic filler than the resin layer on the element side, and the resin layer on the element side contained a black colorant, so that the resin layer on the die side was Contains a white colorant.

In Example 65, the resin layer on the mold side contains more curing accelerator, flame retardant and inorganic filler than the resin layer on the element side.

In Comparative Example 43, the amounts of the compounding agents contained in the resin layer on the element side and the resin layer on the mold side were the same.

The following evaluation test was performed on the obtained resin-encapsulated semiconductor device.

A thermal cycle test (TCT test) for investigating the thermal shock resistance and a pressure cooker test (PCT test) for investigating the humidity resistance reliability were conducted in the same manner as in Example 1. A moisture resistance reliability test after IR reflow was performed in the same manner as in Example 23.

Table 32 shows the evaluation results.

[0309]

[Table 32] In comparison with Comparative Example 43, Example 59 using a resin sheet in which the compounding amount of two kinds or three kinds of compounding agents among the compounding agents of the curing accelerator, the flame retardant, the filler and the colorant is changed.
Therefore, in the resin-encapsulated semiconductor device of Example 65, the thermal shock resistance test, the humidity resistance test, and the reliability after IR reflow were significantly improved. Example 66 The EPROM can be sealed by changing the composition of the colorant. Since the EPROM package requires a glass window for irradiating light in order to erase the information stored in the ROM, the ceramic sealing method requires complicated steps and requires high temperature. For this reason, an EPROM is manufactured by a two-step molding method in which a transparent resin is molded on the element only by a transfer molding method instead of the glass window, and then the other portion is transfer molded with a usual sealing resin composition. May be manufactured. This process is complicated, and
There is a problem that high temperature is required.

However, according to the present invention, it can be easily created.

As shown in FIG. 9A, first, the resin composition 4
A sheet of 35 mm × 11 mm × 500 μm is formed using the resin No. 1 and a hole having a diameter of 6 mm is formed in the center with a punch. A transparent resin of a resin composition 50 not containing a colorant, molded into a diameter of 5.5 mm and a thickness of 500 μm, was put into the hole described above, and was heated and compressed by a press to have a thickness shown in FIG. 9B. A resin sheet 25 for encapsulation having a colorant concentration of 400 μm and a transparent window is formed. At this time, the two kinds of resins are mixed at the interface and integrated. After that, FIG.
As shown in (a), this sheet 25 is arranged on the active surface side of the element, and a 35 mm × 11 mm × 400 μm sheet molded using the resin of the resin composition 41 is arranged on the back surface side, and thermocompression bonding is performed by a press. Figure 1 shows the package
A resin-sealed EPROM was manufactured by sealing as in 0 (b). The size of the package after molding is 37 mm x 12 mm
× 740 μm.

By this manufacturing method, the molding of the package can be simplified, the productivity is improved, and since heating at high temperature such as ceramics sealing is not required, damage to the element can be reduced. . Reference Example 8 First, a resin composition having a ratio shown in Table 33 was obtained.

[0313]

[Table 33] The components used are as follows.

First epoxy resin: YX-4000H
(4,4'-bis (2,3-epoxypropoxy)-
3,3 ′, 5,5′-tetramethylbiphenyl, made of oiled shell epoxy, epoxy equivalent 193, melting point 100 ° C. Second epoxy resin: Epicoat 1001 (bisphenol A type epoxy resin, made by Yuka Shell Epoxy Co., Ltd., Epoxy equivalent 480, softening point 68 ° C) Third epoxy resin: Epicoat 807 (bisphenol F type epoxy resin, manufactured by Yuka Shell Epoxy Co., epoxy equivalent 170, viscosity 30Ps) Fourth epoxy resin: ESX-221 (Sumitomo Chemical) Made, epoxy equivalent 220, softening point 85 ° C. Fifth epoxy resin: ESCN-195XL (orthocresol novolac type epoxy resin, Sumitomo Chemical, epoxy equivalent 197) First phenol resin: BRG-556 (Showa High Polymer) , Phenol novolac resin, hydroxyl equivalent 104) Silane cup Ring agent: A-187 (manufactured by UCC) Carbon black: CB-30 (manufactured by Mitsubishi Kasei) Curing accelerator: C17Z (manufactured by Shikoku Kasei, heptadecyl imidazole) Silicone gel: Heat curing type addition type silicone gel MBS: Average particle size Diameter 30 μm Release agent: Ester wax Adhesiveness imparting agent: Zr chelate Flame retardant aid: Antimony trioxide Fused silica: PK451 (maximum particle size 40 μm or less) First, in a universal mixer, at a temperature above the softening point of the phenol resin. The silicone gel and MBS powder that had been melted by heating and dispersed in a curing agent in advance were added, and then stirred and mixed.
Further, the mixture was kneaded by using three rolls and uniformly dispersed so that the maximum particle diameter was about 50 μm. Then, each component was kneaded with the two rolls, and the uncured resin composition 66-73 was obtained.

The resin compositions 67, 69 and 71 contain an adhesion-imparting agent, the resin composition 73 contains a release agent, and the remaining resin compositions do not contain any of them.

(Evaluation of Adhesiveness of Resin Composition) The resin compositions 66 to 73 were molded on the polyimide passivation film coated on the element, and the adhesive force with the polyimide passivation film was measured to give Table 34. Summarized in. Regarding the resin composition 72, a resin surface coated with a release agent and an adhesiveness imparting agent was molded, and the adhesive strength was measured in the same manner.

[0317]

[Table 34] Each resin composition had an adhesive strength as shown in Table 34. By thus combining the resin compositions having different adhesive strengths, the encapsulating resin sheet of the present invention can be obtained.

(Evaluation of characteristics of package after sealing) After rolling the resin composition to a predetermined thickness using a press, Table 3
As shown in FIG. 5, they were combined and heat-pressed by a press, and further rolled to obtain resin sheets for sealing the element active surface side and the element back surface side.

The semiconductor chip was sealed using each sheet to obtain the packages of Examples 67 to 76 and Comparative Examples 44 and 45. Specifically, a cold blade is pressed against the heated sheet to cut it into a size of 14 mm × 14 mm, and then it is placed above and below the TAB semiconductor chip, and 175 ° C.
The package was molded by thermocompression bonding with a press die for minutes.
After that, after-cure for 8 hours at 180 ℃,
A package having a size of 5 mm × 15 mm was obtained. In addition,
At least one of a release agent and an adhesiveness-imparting agent was applied to the sheets used in Examples 73 to 76.

The state of the sheet is shown in FIG. Bump 11
Sealing resin sheets 108 and 109 are attached to the upper surface and the lower surface of the chip 107, which are connected to the leads 113 of the film carrier 106 via 2, respectively. The sealing resin sheets 108 and 109 are a resin sheet 108a having high adhesiveness, a sheet 108b having low adhesiveness, and a resin sheet 109a having high adhesiveness, respectively.
And a sheet 109b having low adhesiveness. If necessary, the adhesiveness imparting agent 114 and the release agent 11 may be provided on the element-side surface and the die-side surface of the resin sheet, respectively.
Apply 5.

[0321]

[Table 35] The following tests were conducted for each example. (1) Thermal shock resistance For each package, -65 ℃ ~ room temperature ~ 150 ℃ 1
The cycle of cooling and heating was repeated for 100 to 1000 cycles, and the defect occurrence rate was examined by checking the operation characteristics of the device. (2) Moisture resistance reliability After each package was left in a pressure cooker at 2.5 atmospheric pressure for 100 to 1000 hours, the defect occurrence rate was examined in the same manner as in (1). (3) Solder resistance to soldering Each package is placed in an atmosphere of 85 ° C and relative humidity of 85%.
After leaving it for 2 hours to absorb moisture, it was immersed in a solder bath at 240 ° C. for 30 seconds. At this point, the crack occurrence rate of the package was examined. Further, the defect occurrence rate after leaving this solder immersion package in a pressure cooker in a saturated steam atmosphere at 127 ° C. for 100 to 1000 hours was examined in the same manner as described above.

The results obtained are summarized in Table 36 below.

[0323]

[Table 36] As shown in Table 36, the packages produced by the method of the present invention (Examples 67-76) are Comparative Examples 44 and 4.
The reliability is better in the thermal cycle test and the pressure cooker test than the package of No. 5. In particular, in the crack generation rate after solder immersion and the pressure cooker test, it is found that the example has better reliability than the comparative example, and the adhesiveness between the semiconductor element and the sealing resin sheet is excellent.

As described in detail above, according to the present invention, the uncured resin sheet is used for sealing because the adhesive strength of the surface in contact with the element is greater than the adhesive strength of the surface in contact with the mold.
Provided is a method for manufacturing a semiconductor device, which has good adhesiveness between a semiconductor element and a sealing resin and also has excellent releasability from a mold.

As described above, since the semiconductor device in which the sealing resin is adhered to the element in a good state is manufactured, good reliability can be assured for a long period of time.

[0326]

As described above, the compounding agent necessary for obtaining the necessary properties can be compounded only in the necessary part of the resin sheet. Therefore, the characteristics can be improved by increasing the amount of the compounding agent in a certain portion, and the unnecessary compounding agent can be reduced in the certain portion, so that the characteristic can be improved.

Therefore, in the resin-encapsulated semiconductor device according to the present invention, a package which can simultaneously satisfy the following characteristics can be obtained. (1) High reliability and high thermal conductivity (2) High productivity and high reliability (3) High flame retardancy and high reliability (4) High strength and high reliability (5) Low cost and high resistance to α rays Reliability (6) Reflow resistance and marking characteristics (7) Moisture resistance and high reliability (8) Thermal shock resistance and high reliability As a result of the above, according to the present invention, a resin-sealed mold having good reliability over a long period of time. A semiconductor device can be manufactured.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a manufacturing process of a resin-sealed semiconductor device of the present invention.

FIG. 2 is a diagram showing a molding method of the resin-encapsulated semiconductor device of the present invention.

FIG. 3 is a diagram showing a method for producing a sealing resin sheet.

FIG. 4 is a diagram showing a method for producing a resin sheet in which the concentrations and types of compounding agents are gradually changed.

FIG. 5 is a diagram showing a method for molding a resin-encapsulated semiconductor device using a sheet in which the concentration of a compounding agent continuously changes.

FIG. 6 is a sectional view showing the structure of a resin-sealed semiconductor device of the present invention.

FIG. 7 is a cross-sectional view showing a LOC (Lead on Chip) type package.

FIG. 8 is a diagram illustrating a warp amount (%).

FIG. 9 is a diagram showing a sealing resin sheet for an EPROM.

FIG. 10 is a diagram showing a method for molding a resin-sealed EPROM.

FIG. 11 is a cross-sectional view showing a sealing resin sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Element active surface side sealing resin sheet 2 ... Element back surface side sealing resin sheet 3 ... Lead wire or wire 4 ... Bump 5 ... Semiconductor element 7 ... Frame (polyimide film carrier) 8 ... Outer mold 8a ... Upper outer mold 8b ... Lower outer mold 9 ... Inner mold 9a ... Upper inner mold 9b ... Lower inner mold 10 ... Die pad 11 ... Lead frame 12 ... High thermal conductive sealing resin 13 ... Sealing with good moldability Stop resin 14 ... AIN ceramics plate 15 ... Al heat sink 16 ... Horizontal surface 17 ... Resin-sealed semiconductor device 18 ... Compounding agent component 19 ... Encapsulating resin sheet with different compounding agent concentration 20 ... Concentration and type are continuous Resin sheet for sealing 21 ... Large resin sheet 22 ... Small resin sheet 23 ... Cured resin sheet 24 ... Resistance wire 25 ... EPROM sealing resin sheet 10 0 ... Supply reel 106 ... Polyimide film carrier 107 ... Semiconductor element 108 ... Element back side sealing resin sheet 109 ... Element active side sealing resin sheet 112 ... Bump 113 ... Lead wire 114 ... Adhesion imparting agent 115 ... Release Molding agent 200 ... Semiconductor element (chip) mounting portion 300 ... Sheet attaching portion 400 ... Press molding portion 401 ... Mold 402 ... Heater 500 ... Winding reel

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location H01L 23/29 23/31 // B29K 105: 06 (72) Inventor Sadao Kajiura Sachio Kawasaki, Kanagawa Prefecture Komukai-Toshiba-cho No. 1 Inside the Toshiba Research and Development Center Co., Ltd. (72) Inventor Akira Zenzumi Komukai-Toshiba-cho No. 1 Inside the Toshiba Research and Development Center, Kawasaki City, Kanagawa Prefecture

Claims (16)

[Claims] 1. A method of manufacturing a resin-encapsulated semiconductor device, comprising: a step of disposing a sealing resin sheet on the surface of a semiconductor element; and a step of melting and curing the sealing resin sheet in a mold. The method for producing a resin-encapsulated semiconductor device, wherein the encapsulating resin sheet has a different distribution of the compounding agent on the surface in contact with the semiconductor element and on the other surface. 2. The method for producing a resin-encapsulated semiconductor device according to claim 1, wherein the compounding agent compounded in the encapsulating resin sheet is a curing accelerator, a coloring agent, a release agent, or an adhesiveness-imparting agent. ,
A method for manufacturing a resin-encapsulated semiconductor device, which is at least one selected from a flame retardant and a filler. 3. The method of manufacturing a resin-encapsulated semiconductor device according to claim 1, wherein the surface of the encapsulating resin sheet in contact with the element and the other surface have different concentrations or kinds of compounding agents. A method of manufacturing a resin-encapsulated semiconductor device. 4. The method for producing a resin-encapsulated semiconductor device according to claim 1, wherein the compounding agent contained in the encapsulating resin sheet is continuously distributed from the surface in contact with the element toward the other surface. A method of manufacturing a resin-encapsulated semiconductor device, which is characterized by changing. 5. A method of manufacturing a resin-encapsulated semiconductor device, comprising: a step of disposing a sealing resin sheet on the surface of a semiconductor element; and a step of melting and curing the sealing resin sheet in a mold. The method for producing a resin-encapsulated semiconductor device, wherein the encapsulating resin sheet has a different distribution of a compounding agent in a region in contact with a semiconductor element and a lead wire and in other regions. 6. The method for producing a resin-encapsulated semiconductor device according to claim 5, wherein the compounding agent compounded in the encapsulating resin sheet has a large diameter filler, crushed filler, flaky filler, and fibrous filler. A method for producing a resin-encapsulated semiconductor device, wherein the concentration of the compounding agent is at least one selected from, and is low in a portion in contact with the element and lead wire in the resin sheet and high in other portions. . 7. The method for manufacturing a resin-encapsulated semiconductor device according to claim 5, wherein the compounding agent compounded in the encapsulating resin sheet is a filler, the diameter of the filler is partially small, and A method for manufacturing a resin-encapsulated semiconductor device, which is large in a portion. 8. A method of manufacturing a resin-sealed semiconductor device, comprising: a step of disposing a sealing resin sheet on a surface of a semiconductor element including an EPROM; and a step of melting and curing the sealing resin sheet in a mold. A method of manufacturing a resin-encapsulated semiconductor device, wherein the distribution of the colorant is different between the portion in contact with the EPROM element and the other portion. 9. A method of manufacturing a resin-sealed semiconductor device, comprising: a step of disposing a sealing resin sheet on the surface of a semiconductor element; and a step of melting and curing the sealing resin sheet in a mold. The method for producing a resin-encapsulated semiconductor device, wherein the encapsulating resin sheet has an adhesive force between a surface in contact with an element and an element that is greater than an adhesive force between an opposite surface and a mold. 10. A resin-sealed semiconductor device comprising a sealing resin portion and a semiconductor element sealed by the sealing resin portion, wherein the sealing resin portion is for sealing in contact with the semiconductor element. 1. A resin-encapsulated semiconductor device comprising a resin layer and an encapsulating resin layer located outside the semiconductor device, wherein each encapsulating resin layer has a different distribution of a compounding agent contained therein. 11. The resin-encapsulated semiconductor device according to claim 10, wherein the compounding agent compounded in the resin layer for encapsulation is a curing accelerator, a colorant, a release agent, an adhesiveness-imparting agent, a flame retardant. And a resin-encapsulated semiconductor device, which is at least one selected from fillers. 12. The resin-encapsulated semiconductor device according to claim 10, wherein the layer of the encapsulating resin layer in contact with the element and the layer located outside the semiconductor device have different concentrations or types of compounding agents. A characteristic resin-encapsulated semiconductor device. 13. The resin-encapsulated semiconductor device according to claim 10, wherein the distribution of the compounding agent continuously changes from the layer in contact with the element toward the layer located outside the semiconductor device. Resin-sealed semiconductor device. 14. A resin-sealed semiconductor device comprising a sealing resin portion and a semiconductor element sealed by the sealing resin portion, wherein the sealing resin portion is on an upper surface of the semiconductor element. And a second resin layer on the lower surface of the semiconductor element, a: coefficient of thermal expansion of first resin layer (K ^-1 ) b: elastic modulus of first resin layer (Pa) c: Resin thickness of first resin layer (mm) d: Thermal expansion coefficient (K ^-1 ) of second resin layer e: Elastic modulus (Pa) of second resin layer f: Resin of second resin layer A resin-encapsulated semiconductor device, which has a thickness (mm) in a range of 0.8 <(abc) / (def) <1.2. 15. The resin-encapsulated semiconductor device according to claim 14, wherein: L: thickness of the resin-encapsulated semiconductor device, L ′: horizontal when the molded resin-encapsulated semiconductor device is left on a flat surface. The resin-encapsulated semiconductor device is characterized in that the maximum height measured from another plane is {(L'-L) / L} <0.06. 16. A resin sheet for encapsulation, which is disposed on the surface of a semiconductor element and seals a semiconductor element by being melted and cured, the resin sheet being a resin sheet on the surface in contact with the element and on the other surface. The distribution of the compounding agent contained is different, and the compounding agent is at least one selected from a curing accelerator, a colorant, a release agent, an adhesion promoter, a flame retardant and a filler. Resin sheet for encapsulation.