WO2005036453A1

WO2005036453A1 - Card incorporating semiconductor

Info

Publication number: WO2005036453A1
Application number: PCT/JP2004/015185
Authority: WO
Inventors: Akira Urakami
Original assignee: Japan Gore-Tex Inc.
Priority date: 2003-10-07
Filing date: 2004-10-07
Publication date: 2005-04-21

Abstract

A card incorporating semiconductor comprising a substrate on which a semiconductor is mounted and a card frame, characterized in that a stress relaxation layer is interposed between the substrate and the card frame. The stress relaxation layer is a resin film, for example. It is recommended that it has a tensile elastic modulus of about 1-1300 Mpa and a tensile elongation at break of about 5% or above. The stress relaxation layer preferably has a porous structure. According to this inventive card, separation between the card frame and the substrate on which the semiconductor is mounted can be suppressed to a high degree when a bending stress is applied, while satisfying the requirement of reduction in size and thickness.

Description

Description Technical field of semiconductor built-in card

The present invention relates to a semiconductor built-in card represented by an IC card and a memory card.

-. Background Technology

For memory cards used as recording media in electronic devices such as digital cameras and mobile phones, and cards with built-in semiconductors such as IC cards, there is a demand for larger recording capacity and smaller and thinner devices. Are increasing year by year.

Under these circumstances, semiconductors (semiconductor elements) used in cards with built-in semiconductors are required to have a large capacity and a small size, and a board on which such a semiconductor is mounted (semiconductor mounting board) is required. The card frame for holding is required to be thin and small.

-In many cases, -notes are used for exchanging data between digital cameras and computers, etc., and devices (digital cameras and computers) are used. In general, when a card is inserted into or removed from a slot, the card frame is grasped with a finger. Also, in the case of an ic card, the card frame portion is gripped by a finger when the card is taken out of the card case.

As described above, in the above-described card with a built-in semiconductor, the card frame portion is usually gripped by a finger due to its usage, and at this time, stress is applied vertically to the card frame surface. , Card frame When a part of the semiconductor device is gripped by a finger and the other part is held by a slot of the device, the semiconductor built-in force K is subjected to bending stress. Generally, a semiconductor mounting board has a high strength and is hardly deformed even when subjected to the bending stress as described above. On the other hand, since the force frame is usually smaller in strength than the semiconductor mounting board and easily deformable, when the semiconductor built-in force is subjected to the above-mentioned bending stress, the force of the card frame is reduced. There is a problem that the semiconductor mounting substrate cannot follow the deformation, and the semiconductor mounting substrate easily peels between frames. Since the built-in semiconductor chip is frequently inserted and removed in the device slot, it is frequently subjected to bending stress (that is, repeatedly subjected to bending stress). There is a demand for a high degree of suppression of delamination between frames.

The strength of the card frame or the built-in semiconductor card and the strength of the whole

>

It is conceivable that the bending stress is increased to make it difficult to be deformed by the bending stress. The strength of the force frame related to the built-in semiconductor card and the built-in semiconductor card

Techniques that can improve the overall strength of K include, for example,

A method of introducing and reinforcing a frame is disclosed in Japanese Patent Application Laid-Open No. 5_968889. The first card frame holding the semiconductor mounting substrate is replaced with the second card frame. There are a covering technique (Japanese Patent Application Laid-Open No. Hei 6-15992) and a method of introducing a rigid support into the card frame to reinforce it (Japanese Patent Application Laid-Open No. Hei 7-17575). If these technologies are applied, it is possible to suppress the deformation of the card frame (the entire card with a built-in semiconductor) when receiving the above bending stress, and to suppress the separation between the semiconductor mounting board and the card frame. is there.

However, the above-mentioned Japanese Patent Application Laid-Open Nos. Hei 5-966989 and Hei 6-96 introduce a reinforcing material such as a metal frame, a second card frame, and a support. The technology of Japanese Patent Application Laid-Open No. 15992/1995 and Japanese Patent Application Laid-Open No. 7-171575 meet the demand for miniaturization and thinning in order to increase the size and thickness of the entire semiconductor built-in card. Is not enough.

The present invention has been made in view of the above circumstances, and an object of the present invention is to meet the demand for miniaturization and thinning, and to reduce the distance between a semiconductor mounting board and a card frame when a bending stress is applied. An object of the present invention is to provide a semiconductor built-in card in which peeling of the semiconductor is highly suppressed. Disclosure of the invention

The card with a built-in semiconductor of the present invention, which has achieved the above object, includes a substrate on which a semiconductor is mounted and a card frame as constituent elements, and a stress relaxation layer is interposed between the substrate and the force frame. The gist exists where it is. The stress relaxation layer is preferably made of a resin film. The resin film has a tensile modulus of 1 to 130 MPa and a tensile elongation at break of 5%. It is desirable that this is the case.

In addition, the stress relaxation layer preferably has a porous structure-more preferably, is more preferably made of an expanded porous polytetrafluoroethylene (PTFE film). It is recommended that the porosity of the stretched porous polytetrafluoroethylene film be 30 to 95%, and the thickness of the resin film constituting the stress relaxation layer is 0%. The adhesive layer A is interposed between the stress relieving layer and the substrate, and also between the stress relieving layer and the card frame. It is a preferred embodiment of the present invention that the adhesive layer B is interposed and the stress relaxation layer is fixed to the substrate and the card frame by the adhesive layers A and B. Peel strength at interface with adhesive layer A The peel strength at the interface between the card frame and the adhesive layer B is, for example, 0.4 N / mm or more. The adhesive layer A and the adhesive layer B may be composed of different adhesives. The adhesive of the adhesive layer A is a thermosetting resin (particularly preferably an epoxy resin), and the adhesive of the adhesive layer B is a thermoplastic. Resins (particularly preferably polyester resins) may be used. It is recommended that the product of the tensile modulus and the thickness of the adhesive layer B be 50 MPa amm or less. In addition, as the adhesive layer A and / or the adhesive layer B, those obtained by filling an adhesive in pores of an expanded porous polytetrafluoroethylene film are usually used.

The term “film” in this specification is a concept that includes a so-called “sheet”. Brief Description of Drawings

FIG. 1 is a schematic diagram showing an example of the structure of a semiconductor built-in card (memory card) of the present invention.

FIG. 2 is a sectional view taken along line 11 of the memory card of FIG.

FIG. ₃ is an enlarged view showing a state where the semiconductor built-in force of the present invention is subjected to bending stress. BEST MODE FOR CARRYING OUT THE INVENTION

By interposing a stress relaxation layer between the semiconductor mounting substrate and the card frame, the present inventor has realized the above-described semiconductor built-in card using a card frame having a lower strength than the semiconductor mounting substrate. We have found that peeling between the semiconductor mounting substrate and the card frame when subjected to bending stress can be suppressed. Further, the stress relaxation layer is formed of the above-mentioned JP-A-5-96889, JP-A-6-15992, and JP-A-7-171975. Unlike the reinforcing material disclosed in the gazette, since the above-mentioned peeling suppressing effect can be ensured in a relatively thin form, the thickness of the semiconductor built-in card can be reduced. Since the second card frame is not required as in Japanese Patent Publication No. 92, it has been found that the card with a built-in semiconductor can be reduced in size, and the present invention has been completed. FIG. 1 shows an example of a semiconductor built-in card (memory card) of the present invention. In Fig. 1, 10 is a semiconductor built-in card,

11 is a card frame, 12 is a semiconductor mounting board, and 13 is a connection terminal. FIG. 2 is a cross-sectional view taken along the line 11 in FIG. 1, and reference numeral 14 denotes a stress relaxation layer (layers to be described later are not shown). Hereinafter, the present invention will be described in detail.

The above-mentioned semiconductor mounting board is one in which one or more semiconductor elements are mounted on a board (circuit board) on which a circuit is formed. The semiconductor mounting board used for the semiconductor built-in card of the present invention is not particularly limited. For example, a card used for a semiconductor built-in card such as a conventionally known memory card or IC card can be applied as it is.

As specific examples, examples of semiconductor chips include a memory made of silicon arsenic arsenic and a computer with a V-chip microphone. In the case of -memory-------------------------------------------------------------------------------------- MRAM (Magnetic

R AM), F E R AM (F e r o e l e c t r i c R AM) may also be used. In the case of an IC force, a CPU (Central Integrated Circuit) may be used in addition to the above memory. In some cases, resistors and capacitors are mounted on a semiconductor mounting board together with such a semiconductor element.

As a material of the substrate (circuit board), for example, a glass fiber-epoxy resin composite (so-called glass epoxy) or glass BT (bismalei) Known materials such as medium triazine), ceramics and polyimide film are applicable.

On a substrate on which a semiconductor is mounted, it is common to seal mounting components such as semiconductor elements with a sealing resin. As the sealing resin, a conventionally known epoxy resin compound or the like can be applied. The thickness of the semiconductor mounting board after resin sealing is generally 3 mm or less.

If components (such as semiconductor elements) are mounted on one side of the semiconductor mounting board, the connection terminals for transmitting and receiving information to and from the outside should be provided on the opposite side of the component mounting side of the semiconductor mounting board. (Figure 1 illustrates this aspect). However, the connection terminals are not limited to these locations, and may be formed on the component mounting surface side when the semiconductor mounting board has components mounted on both sides or depending on the structure of the semiconductor built-in card. . Further, in the case of a non-contact type memory card or IC card, a non-contact type data communication means having an antenna or the like can be provided instead of the connection terminal.

The card frame is generally made of resin. As a constituent resin, a resin that satisfies the function as a frame of a semiconductor built-in card can be obtained. it can. Since the card frame is generally formed by an injection molding method, a resin suitable for injection molding can be preferably used. Specific examples include ABS (acrylonitrile-butadiene-styrene), polycarbonate, polyester (polybutylene terephthalate, etc.). For the purpose of reinforcing or coloring the card frame, various known reinforcing materials and coloring agents (such as rod-shaped, fibrous, and particulate boilers) can also be added.

The shape of the card frame is not particularly limited. Just do it. For example, there are shapes used in conventionally known semiconductor memory cards such as various memory cards and IC cards.

Note that, as described later, the stress relaxation layer preferably has a porous structure. However, when bonding the card frame to the semiconductor mounting board, heat is usually applied, so that a problem may occur due to expansion of the air in the pores of the stress relaxation layer. is there. Therefore, the shape of the force frame should be designed in the card frame semiconductor mounting board installation part so that after the semiconductor mounting board is installed, there is a gap to allow the above-mentioned expanded air to escape. Is recommended. The width of the gap is preferably, for example, not less than 0.1 mm. If the width of the gap is smaller than the above range, the expanded air escapes. The width of the gap may be, for example, 0.2 mm or less.o The smaller the width of the gap, the easier the force frame becomes / J and molding.o

The stress relieving layer is a layer that relieves bending stress applied to the card frame (built-in semiconductor chip).

The phenomenon when an overstress is applied will be described with reference to FIG. Figure

3 is the connection when the semiconductor built-in power cord of the present invention is subjected to the above bending stress.

-The appearance of the connection terminal 13 near-near the side is shown in an enlarged manner.- In the semiconductor built-in force 10 shown in Fig. 3, the stress relaxation layer 14 is an adhesive layer 15 , 15 and are bonded to the force frame 11 and the semiconductor mounting substrate 12.

When the above-described bending stress is applied to the card with built-in semiconductor and the card frame 11 is deformed, the stress relaxation layer 14 is deformed without peeling off from the card frame 11, but the bending stress is reduced. Since the stress is relieved in the layer 14, the stress transmitted to the semiconductor mounting substrate 12 is greatly reduced. Therefore, the interface separation between the stress relaxation layer 14 and the semiconductor mounting substrate 12 is also suppressed, and as a result, the separation between the semiconductor mounting substrate and the card frame is high. Is suppressed. At this time, the stress relieving layer 14 extends in the thickness direction, and the elongation in the thickness direction greatly contributes to suppression of separation between the card frame 11 and the semiconductor mounting substrate 12.

Preferably, the stress relaxation layer is formed of a resin film. The force S. Such a resin film has a tensile elastic modulus of IMPa to 130 OMPa and a tensile elongation at break of 5% or more. Is preferred. The present inventors have found that the presence or absence of the function of extending the stress relaxation layer in the thickness direction can be alternatively evaluated by the tensile elastic modulus and the tensile elongation at break of the resin film constituting the stress relaxation layer. Was found. In other words, a stress relaxation layer composed of a resin film having a tensile elastic modulus satisfying the above range and a tensile elongation at break equal to or greater than the lower limit above has a good function of extending the stress relaxation layer in the thickness direction. Therefore, the separation between the semiconductor mounting substrate and the card frame can be more highly suppressed. The tensile modulus is more preferably 5 MPa or more and 80 OMPa or less, and the tensile elongation at break is more preferably 20% or more, still more preferably 30% or more. .

If the tensile modulus exceeds the above range or the tensile elongation at break falls below the upper limit, the stress relaxation layer has a small elongation in the thickness direction. In addition, the relaxation of the bending stress in the stress relaxation layer may be insufficient. Furthermore, when the tensile rupture elongation is lower than the above lower limit value, the stress relaxation layer may be broken when the internal semiconductor card receives a large bending strain. If the tensile modulus is lower than the above range, the stress relaxation layer may be unnecessarily deformed and broken. Further, it is preferable that the resin film constituting the stress relaxation layer is an adhesive laminated film in which adhesive layers are provided on both sides in advance, and then is used for bonding the card frame to the semiconductor mounting substrate. (Details will be described later.) In the case of a resin film having a tensile modulus lower than the above range, the adhesive laminate film is used. If a compressive stress is applied during passage between rolls during the production of a roll, a production problem such as difficulty in maintaining the thickness may occur.

The above tensile modulus and tensile elongation at break were determined by JISK71

It is a value obtained by measuring under the conditions described in the examples described below in accordance with the provisions of 13 o

There is no particular limitation on the material constituting the stress relaxation layer, and polyolefin resins such as polyethylene (PE) and polypropylene (PP); Nylon 6, Nylon 66, etc. Polyamide resins; Polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate; Polyurethane resins; Ataryl resins;

Fluorine-based resins such as TFE, tetrafluoroethylene, and polyethylene copolymers.

The stress relieving layer preferably has a porous structure. For example, a void-containing film such as a foam film, a woven fabric, a non-woven fabric, or a porous film such as a stretched porous finolem constitutes the stress relieving layer. It is mentioned. If the stress relieving layer has a porous structure, the adhesive is used to integrate the semiconductor mounting board with the adhesive layer through the stress-relaxation process. The volatile components contained in the water can escape through the pores. As a result, it is difficult for voids to be formed at the interface between the adhesive and the adherend, and it is possible to prevent a decrease in adhesive strength due to generation of voids. Also, when assembling a semiconductor built-in card, if the semiconductor mounting board and the card frame are thermocompression bonded via a stress relaxation layer, there is a problem that the card frame is easily deformed by heat. If the layer has a porous structure, if it is heated from the semiconductor mounting substrate side, the stress relaxation layer plays the role of a heat insulating layer, making it difficult for heat to be transmitted to the card frame side. Can be prevented. As the stress relaxation layer having a porous structure, a porous film made of a fibrous or fibrous resin is preferable. In the case of a stress relaxation layer composed of such a porous film, when the built-in semiconductor card is subjected to bending stress, it is greatly deformed, and even if the fiber is stretched so that the fiber / fibril is released, the stress is reduced. When the stress is removed, the fiber / fibril is folded by the elastic recovery force of the card frame, and the shape of the stress relaxation layer is easily restored to the original state. There is an advantage that warpage (permanent strain) hardly remains.

In particular, if the stress relaxation layer is formed of a porous film having extremely fine fibrils, the above-mentioned recovery effect is remarkable. Therefore, as the stress relaxation layer, a stretched porous PTFE film is particularly preferable because it can form an extremely thin fibril by stretching, has a large tensile elongation at break, and has an appropriate tensile modulus.

Since the card with a built-in semiconductor is gripped by a finger when using the card, it is usually made of a solid material so as to withstand the compressive force at this time. The idea of forming a part with a porous structure is entirely new. -When the card with built-in semiconductor is crushed in the thickness direction when it is gripped by a finger-The position of the terminal part is lowered, and when the card with built-in semiconductor is inserted into the slot of the device, the built-in semiconductor Poor contact between the card terminals and equipment terminals may occur. The present inventor has found that even when the material constituting the stress relaxation layer is a porous structure, the card with a built-in semiconductor is gripped with a finger by using a material having a tensile elasticity satisfying the above range. It has been found that it can withstand the compressive force at the time.

The above-mentioned expanded porous PTFE film is disclosed in JP-A-46-7284, JP-A-50-22881, and Tokuhyohei 3-5 0 4 876. Publications and the like include those disclosed. In other words, PTFE A paste obtained by mixing fine powder (having a crystallinity of 90% or more) with a molding aid is molded, the molding aid is removed from the molded body, and then a high temperature [melting point of PTFE (approximately 32) Temperature of less than 7 ° C), for example, about 300 ° C] It is obtained by stretching at a high speed and, if necessary, baking.

At the time of stretching, uniaxially stretched porous PTFE film can be obtained by stretching only in the MD direction (longitudinal direction at the time of manufacturing the stretched porous PTFE film) or TD direction (direction orthogonal to the MD direction). If the film is stretched biaxially in the direction and the TD direction, a biaxially stretched porous PTFE film can be obtained. As the stress relaxation layer of the present invention, any of a uniaxially stretched and a biaxially stretched porous PTFE film may be used. However, since the mechanical anisotropy and the electrical anisotropy are small, biaxial stretching is preferred. Expanded porous PTFE films are more preferred.

By the way, in a uniaxially stretched porous PTFE film, the nodes (folded crystals) are thin islands perpendicular to the stretching direction, and the interlocking buoyrils (folded crystals) are connected to connect the nodes. (A linear molecular bundle that has been melted and pulled out) is oriented in the stretching direction. The space between the fibers or the space defined by the buoyril and the suds has a fibrous structure with pores. In the biaxially stretched porous PTFE film, the fibrils spread radially, the nodes connecting the buibrils are scattered in islands, and the spider web has many spaces defined by the fibrils and the nodes. It has a fibrous structure.

The porosity of the expanded porous PTFE film is preferably from 30% to 95%, more preferably from 50% to 90%. If the porosity is too small, the tensile modulus may exceed the above range, and the stress relaxation layer using such a film may not sufficiently reduce the bending stress. On the other hand, the porosity is too large

1 In this case, the mechanical strength of the film is remarkably reduced, which may cause the film to fall below the lower limit of the tensile modulus, and may also deteriorate the handling property (handling property) at the time of processing.

The porosity is determined based on the apparent density _{P l} (g / cm ³ ) of the expanded porous PTFE film measured according to the provisions of JISK6885 and the density of PTFE 0 (2.2 g / cm ³ ). ³ ) The following formula

Porosity (%) = 1 0 0 X (p 0-ι) / P 0

Is a value obtained by using The porosity values of the expanded porous PTFE film in this specification are all measured by this method. Further, the maximum pore size of the stretched porous P-TFE film is preferably from 0.1 μm to 20 μm, more preferably from 0.1 μm to 10 μm. . If the maximum pore size of the expanded porous PTFE film is out of the above range, it is difficult to make the tensile modulus and tensile elongation at break within the above ranges.

When the stress relieving layer is formed of a resin film having a porous structure such as an expanded porous PTFE film, the adhesive of the adhesive layer (described later) adjacent to the stress relieving layer becomes the stress relieving layer. The adhesion between the stress-relaxation layer and the adhesive layer is improved due to the An effect or the effect of the penetration into the pores. However, if the maximum pore diameter of the expanded porous PTFE film constituting the stress relaxation layer is less than the above range, the adhesive of the adhesive layer becomes difficult to penetrate into the pores, and the anchor effect tends to be insufficient. It is in. Here, the “maximum pore diameter” is a value measured according to the provisions of ASTM F-316. The maximum pore diameter of the stretched porous PTFE film in this specification is a value measured by this method.

The preferred thickness of the resin film constituting the stress relaxation layer varies depending on the type of the resin film used, the porosity, and the like.

2 In the case of a porous PTFE film, the thickness is generally from 0.05 mm to 0.5 mm. More preferably, the thickness is 0.01 mm or more and 0.3 mm or less, and more preferably 0.03 mm or more and 0.1 mm or less. Also, in the case of other resin films (especially porous films), it is desirable that the thickness is in the above range. If a resin film having a thickness exceeding the above range is used for the stress relaxation layer, it will be difficult to meet the demand for a thinner semiconductor built-in card. On the other hand, in the case of a resin film having a thickness less than the above range, the handleability is impaired due to a decrease in strength and the like.

The thickness of the porous film referred to here is the average thickness measured with a dial gauge (for example, 1/1000 mm Dianoresic Gage manufactured by Techloc) (other than the panel load on the main unit). (Measured under no load). All the thicknesses of the porous film in this specification are values measured by this method.

Adhesion between the stress relaxation layer and the card frame and between the stress relaxation layer and the semiconductor mounting substrate are desirably performed via an adhesive layer (15 in FIG. 3). The adhesive layer is formed by applying a liquid adhesive to one or both of the contact surfaces of the card frame (semiconductor mounting g-plate), the stress relaxation layer, or the adhesive. A method using a film can be adopted.

An adhesive layer having a peel strength of 0.4 N / mm or more, preferably 0.8 N / mm or more is recommended. More specifically, when the adhesive layer between the stress relieving layer and the semiconductor mounting substrate is called an adhesive layer A, and the adhesive layer between the stress relieving layer and the card frame is called an adhesive layer B, the adhesive layer A and the semiconductor At least one (preferably both) of the peel strength A at the interface with the mounting board and the peel strength B at the interface between the adhesive layer B and the card frame are 0.4 N / mm or more (preferably 8 N / mm or more is recommended. Peel strength is too low

Three In this case, separation at the bonding interface is likely to occur, and the stress relaxation effect of the stress relaxation layer cannot be sufficiently obtained.

The peel strength is a value obtained by measuring under the conditions described in the examples described below, in accordance with the provisions of JIS C 6481.

As the adhesive, various adhesives known in the art can be used. The adhesive (adhesive layer) A between the stress relieving layer and the semiconductor mounting substrate and the adhesive between the stress relieving layer and the card frame are used. As the agent (adhesive layer) B, the same material or a different material may be used. However, the adhesive is selected according to the material of the semiconductor mounting substrate (the sealing member, if the substrate is sealed as described below) and the card frame, as described later. Therefore, when the material of the semiconductor mounting substrate (or the sealing member) and the card frame are different, different adhesives A and B are often used.

When the card frame is made of polycarbonate resin, the adhesive B used on the card frame side may be, for example, an epoxy resin, a polyurethane resin, an acrylic resin (a cyanoacrylate resin). And other acrylic resins), polyamide resins (such as nylon 6, nylon 66), -polyester resins-[polyethylene terephthalate-K (PET), Polybutylene terephthalate, a reactive polyester resin described below, etc.), and a nitrile rubber (NBR) resin. If the card frame is made of ABS resin, the adhesive B may be epoxy resin, polyurethane resin, acrylic resin (cyanoacrylate resin, second generation reactive acrylic resin). Resin (SGA), other acrylic resins], polyamide resin, polyester resin [polyethylene terephthalate (PET), polybutylene terephthalate, reactive polyester resin described below, etc.] , NBR resin and the like are adopted. The material of the card frame is Even if different from the ABS resin, epoxy resin, polyurethane resin, acrylic resin, polyamide resin, polyester resin, nitrile rubber (NBR) resin, etc. are used as appropriate. I'm sorry.

As described above, a thermoplastic resin such as a polycarbonate resin is often used for a card frame. Therefore, it is particularly recommended to use a thermoplastic resin as the adhesive B. By doing so, the affinity with the force frame is improved, and the bonding strength to the card frame is improved. In particular, when the card frame is made of a polycarbonate resin, since the polycarbonate has an ester bond, the use of a polyester resin for the adhesive B is advantageous in improving the affinity (adhesion strength). Desirable.

On the other hand, when bonding the semiconductor mounting substrate and the stress relaxation layer, it is common to bond the sealing resin surface of the semiconductor mounting substrate and the stress relaxation layer. When an epoxy resin compound is used as the sealing resin, the adhesive A for bonding the semiconductor mounting board and the stress relieving layer is an epoxy resin, a polyurethane resin, or an acrylic resin. Adhesives such as are preferred, and among them, thermosetting resins (particularly epoxy resins) are particularly preferred because of their excellent adhesiveness. First, even when the sealing resin is other than the epoxy resin, or when the sealing resin is not used, the same resin as described above may be used as the adhesive A.

The epoxy resin used for the adhesive A and / or the adhesive B is a curable compound containing at least two epoxy groups in a molecule. As the curable compound, glycidyl ether of phenols is typical. The glycidyl ethers of the phenols are particularly excellent in curability and cured product properties. The phenols include bisphenol A such as bisphenol A, bisphenol S, bisphenol F, bisphenol AD, and bisphenol A such as hydrogenated bisphenol A. Kind;

Five Nopolak resins such as enol nopolak resin, cresol nopolak resin, and bisphenol A nopolak resin. A compound having one epoxy group in the molecule may be used as a part of these epoxy resins (for example, about 50% by mass or less based on the total amount of the epoxy resin).

When an epoxy resin is used, it is preferable to use a curing agent and a curing accelerator together. Examples of the curing agent include a phenol resin (a resin having at least two phenolic hydroxyl groups in a molecule), dicyandiamide, dicarboxylic dihydrazide, and a reaction product of an epoxy resin and an amide compound. O

Examples of the phenolic resin include phenolic phenolic resin, cresophenolic resin, bisphenol A phenolic resin, phenolic phenolic resin, and polyvinylphenol. No. Examples of dicarponic acid diazide and razide include, for example, adipic dihydrazide, sebacic dihydrazide, and isophthalic dihydrid.

, 1. / „,

Drazid can be exemplified. As a reaction product of the epoxy group and the amine compound, for example, a compound commercially available under the trade name of NOPOCURE J (manufactured by Asahi Kasei Corporation) is used.

These curing agents have a functional group capable of reacting with the epoxy group of the epoxy resin in any case.-3 o Usually, the curing agent is an equivalent ratio of the epoxy group of the epoxy resin to the reactive functional group of the curing agent. (Reactive functional group / epoxy group) is, for example, 03-1 to 5, preferably 05-1

Use within the range of 2.

As the curing accelerator, various conventionally known compounds can be used as the curing accelerator for the epoxy resin. For example, imidazoles (such as 2-ethyl-4-methylimidazole), dicyandiamide derivatives, dicarboxylic dihydrazide, triphenylphosphine, and tetratol Phenol phosphonimulet trafeborate, 21-tetrafluoro-tetrafluorobutyrate, 1,8-diazabicyclo (5,

Metal catalysts such as 4,0) pentacene-1 7-tetraphenyl ester and zinc octylate. The amount of these curing accelerators used is preferably from 0.01 to 5.0 parts by mass, more preferably from 0.05 to 1.0 parts by mass, based on 100 parts by mass of the epoxy resin. Is more preferable.

When a thermoplastic resin is used as the adhesive A and the adhesive B or the adhesive B, a reactive thermoplastic resin (for example, a saturated polyester resin “Hybon 766 3” manufactured by Hitachi Chemical Co., Ltd .; Generation-type reactive acrylic resin). When a reactive thermoplastic resin is used, a cross-linking agent may be added as necessary to appropriately improve the adhesiveness, heat resistance, moisture absorption reliability, and the like. Examples of the cross-linking agent include, in the case of a polyester resin, sociate, block succinate, and melamine resin. When a cross-linking agent is used, it is necessary to appropriately adjust the addition amount so that the cross-linking density is not high and the elastic modulus of the adhesive layer is not too high.

To these adhesives, a thermoplastic resin may be added for the purpose of controlling the viscosity. For example, poly (ethylene terephthalate), poly (phenylene sulfide), polyester sulphone polyether ether ketone, thermoplastic polyester, thermoplastic polyester resin, liquid crystalline polyester (liquid crystalline polyester), tetrafluoropropylene-hexafur. And various thermoplastic resins such as tetrapropylene copolymer, tetrafluoroethylene-perfluoroalkylvinylinoleate copolymer, and tetrafluoronorethylene-ethylene copolymer. They can be used alone or as a mixture of two or more. In addition, for the purpose of improving stress relaxation and flexi- bility, urethane-based, acrylic-based, and

7 A flexible resin such as a rubber-based resin may be added. Furthermore, additives such as surfactants, coupling agents, plasticizers, and flame retardants; fillers such as organic and / or inorganic powders and fibers; May be calories.

Further, these adhesives may be mixed with a component capable of exhibiting tackiness at room temperature, such as an acrylic resin, in order to improve the workability of application.

It is preferable that the adhesive resin is set so that the softening point and the curing temperature after blending are 150 ° C. or less. If the temperature is higher than this, the processing temperature at the time of bonding becomes too high, and the card frame may be deformed.

As a method for forming the adhesive layer by coating, known coating methods such as roll coating, die coating, and spray coating can be employed. The coating may be performed after the viscosity is reduced by adding an organic solvent to the adhesive resin to dilute the adhesive resin or by heating the adhesive resin.

When an adhesive film is used as the adhesive layer, for example, a casting method (formation of an adhesive resin-containing layer by coating on the surface of the release-film; drying if necessary) Can be used, but it is more preferable to use an adhesive film obtained by filling the pores of a porous base material with an adhesive.

For example, an epoxy resin that is suitable as an adhesive has a low viscosity when heated and melted, so the resin flow is large, and it is easy for the resin to protrude from the area to be bonded during bonding. Problems such as dirt may occur. As a method of controlling such a resin flow, an inorganic or organic filler or a rubber component is mixed into an epoxy resin. The viscosity of the resin is too high, which tends to cause problems such as air bubbles during application. On the other hand, if an adhesive film formed by filling the pores of the porous substrate with an adhesive is used, the above problem is solved because the porous substrate plays a role in suppressing the opening of the adhesive resin. Can be avoided. Examples of the porous substrate used for the adhesive film include a porous film such as a void-containing film such as a foamed film, a woven fabric, a nonwoven fabric, and a stretched porous film. It is preferable to use a PTFE film. As described above, since the stretched porous PTFE film has a very fine fibril-node structure, the flow of the adhesive resin can be controlled extremely well. As the expanded porous PTFE film, the same one suitable for the above-mentioned stress relaxation layer can be used.

As a method of filling the adhesive resin into such a porous base material, a kiss roll, a squeeze, a dip, a flow coat, a roll pressure impregnation, and a vacuum with a liquid adhesive resin (varnish) are used. A method of impregnating the pores of the porous base material and drying (solidifying) by a method selected from various methods such as impregnation according to the required accuracy and the like can be adopted. The adhesive resin may be provided as necessary. The viscosity may be reduced by re-diluting the mechanical solvent or by heating, and then subjected to the impregnation.

When the porous base material is a film made of a fluororesin such as an expanded porous PTFE film, for example, the affinity with the bonding resin (the above-mentioned varnish) is low, so that repelling occurs and the bonding occurs. May not be sufficiently filled with resin for use. Therefore, it is recommended to apply a surface treatment to the porous resin film before impregnation to improve the wettability of the adhesive resin (varnish). Such surface treatments include, for example, the following methods (I) to (III) for reducing water repellency.

(I) Physicochemical method The physicochemical method refers to a method of irradiating a porous resin film with plasma, ultraviolet rays, electron beams, or the like, or performing corona discharge treatment. This makes it possible to oxidize or radicalize the surface to lower the water repellency.

(I I) Chemical method

The chemical method is a method in which a compound having lower water repellency than the resin constituting the porous resin film is contained in the film, and the water repellency is reduced by the action of the compound. A compound having such properties is dissolved in a solvent having wettability to the porous resin film, and the resultant is impregnated into a porous resin film. Then, only the solvent is removed to convert the compound into a porous resin film. It can be coated on the surface of the resin film skeleton (the surface of the node and the fiber). Examples of such a compound include polymers having a hydrophilic group (such as a hydroxyl group, an ether group, and a ketone group), such as polyvinyl alcohol, polyvinylinolepyrrolidone, and vinylinoleate / recoholate phthalanolate. In addition to organic polymers such as polyethylene block copolymers, inorganic polymers obtained by a sol-gel reaction from alkoxysilanes and the like can be mentioned.

(I -H-)-Combination of the above-(I)… and (I I-)

A method in which a film (or a group of compounds) whose water repellency is reduced by irradiation or discharge treatment as described in (I) above is contained in the film in advance as in (II) above. . The group of compounds includes, for example, compounds that are activated by absorbing light of a specific wavelength (for example, photo-functionality such as 2,7—2—sodium anthraquinon-2-sulfonate). And a metal salt. If necessary, this compound group is mixed with a halogen ion source, a surfactant, a solvent, and the like, impregnated into a porous resin film, dried, and dried under a predetermined light (for example, a wavelength of 400 nm or less). UV light) The metal ions can be reduced and the metal can be fixed on the surface of the porous resin film. Water repellency can be reduced by the action of the fixed metal.

Examples of the organic solvent used for diluting the adhesive resin include ketones such as acetone, methylethylketone (MEK), methylisobutylketone, cyclohexanone; toluene, xylene, and the like. Aromatic hydrocarbons such as mesitylene; ethylene glycol monomethyl ether, ethylene glycol monoethylene glycol, etc. Esters such as acetate and ethyl acetate; amides such as N, N-dimethylformamide and N, N-dimethylacetamide; and the like, depending on the type of adhesive resin. Or a mixture of two or more. From the viewpoint of reducing the amount of residual solvent after drying, it is desirable to use a low-boiling solvent having a boiling point of 150 ° C or less (especially 130 ° C or less) such as MEK.

For an adhesive film in which the pores of a porous substrate are filled with an adhesive resin, it is desirable to fill the pores with one adhesive resin as much as possible. Specifically, the volume filling ratio of the pores is preferably from 80 to 120% by volume, from 90 to L; more preferably from L to 10% by volume, and from 95 to 10%. More preferably, it is set to 5% by volume. If the filling rate is too low, it may cause porosity and poor adhesion, while if it is too high, the resin flow may become large and the connection terminals may be stained. Here, the case where the filling rate exceeds 100% by volume means a state where the adhesive resin is also present on the surface of the porous substrate.

Considering the productivity of the built-in semiconductor card, an adhesive laminated film in which adhesive layers are formed on both sides of the resin film that constitutes the stress relaxation layer in advance It is also preferable to prepare them. According to this method, the workability at the time of assembling is improved and the thickness accuracy of the adhesive layer is also improved, as compared with the case where a liquid adhesive is applied to the semiconductor mounting substrate or the card frame. An adhesive layer is formed only on one side of the resin film (stress relieving layer) in advance, and when the resin film (stress relieving layer) is laminated on a semiconductor mounting board or a card frame, the remaining part of the resin film (stress relieving layer) is formed. A method of applying a liquid adhesive on one side can also be adopted. To obtain the adhesive laminated film, an adhesive is applied to both sides of the resin film constituting the stress relaxation layer and dried (solidified), or an adhesive is applied to both sides of the resin film constituting the stress relaxation layer. A film (preferably, an adhesive film filled with an adhesive resin in pores of a porous base material) is laminated, and this is treated with a hot press or a hot roll to remove the adhesive resin (part). A method of melting and bonding and integrating can be adopted. It is also possible to apply an adhesive to one side of the resin film, dry it, and bond and integrate the adhesive film on the other side. When forming an adhesive laminated film using a stretched porous PTFE film as a stress relaxation layer, it is possible to improve the wettability between the stress relaxation layer (stretched porous PTFE film) and the adhesive. Good. As a method for improving the wettability with the adhesive, the above-mentioned surface treatment (-) to (-II-I) can be adopted.

When a thermosetting resin is used as the adhesive resin, it is preferable that after forming the adhesive layer, the solvent be dried to be in a semi-cured state (a so-called B stage) and then heat-cured when assembling the semiconductor built-in card.

In general, the thickness of the adhesive layer is not less than 0.01 mm and not more than 0.2 mm. The thickness is more preferably from 0.03 mm to 0.1 mm, and still more preferably from 0.005 mm to 0.05 mm. If the thickness of the adhesive layer is less than the above range, the adhesiveness may be insufficient.If the thickness of the adhesive layer exceeds the above range, the thickness of the semiconductor built-in card becomes too thick, and the resin flow also increases. Too big. The thickness of the adhesive B on the card frame side may be adjusted according to the elastic modulus of the adhesive layer B. When the elasticity of the adhesive layer B is high, the bending stress concentrates on the adhesive interface, and the stress relaxation layer tends not to function sufficiently.Therefore, the adhesive layer is made thinner as the elastic modulus of the adhesive layer becomes higher. It is recommended to avoid concentration of bending stress. For example, it is desirable that the product of the elastic modulus (unit: MPa) and the thickness (unit: mm) of the adhesive layer B is 100 or less, preferably 50 or less. The thickness of the adhesive layer A on the substrate side does not have to satisfy the above numerical range because the adhesive layer A does not actually bend.

In the above adhesive laminated film, it is also preferable to use a release finolem on the surface for the purpose of preventing stickiness and preventing self-adhesion due to aging. As the release finolem, one obtained by subjecting a paper to a release treatment or a resin film is suitably used. The material of the resin film is not particularly limited, but is generally a polyolefin-based resin such as PE or PP; a polyester-based resin such as PET; Also, the resin film has

V Mold resin may be subjected to a release treatment such as a single step of attaching a resin film surface to the resin film.

The following is an example of a method of manufacturing a card with a built-in semiconductor according to the present invention, in which the above-mentioned adhesive laminated film in which adhesive layers are formed on both surfaces of a resin film constituting a stress relaxation layer is used. To explain.

The adhesive laminated film is cut as necessary according to the size of the semiconductor mounting substrate or the mounting portion of the card mounting frame on the semiconductor mounting substrate. Of course, the adhesive laminated film may be supplied in a state of being cut into such a size in advance.

Next, the semiconductor mounting board and the card frame are bonded via the cut adhesive laminated film. At this time, first, either one of the semiconductor mounting board and the card frame is attached to one surface of the adhesive laminated film. It is also possible to adopt a method in which one is adhered and then the other is attached to the other surface. T <Adhesion of semiconductor mounting substrate-adhesive laminated film-one-time frame * ST | P] It is recommended to use a hot press or a hot roll for these bondings.o The surface to be bonded of the semiconductor mounting board or force frame is pre-assembled as necessary to improve the bonding strength. Treatment, corona discharge treatment, and bramer treatment may be performed. Also, the resin used for the sealing resin of the semiconductor mounting substrate and the resin frame often contains a fox component for the purpose of improving the mold release from the mold during molding. Physical or chemical treatment for removal may be applied.

The encapsulation resin used for the semiconductor mounting board is cured after encapsulation molding with a transfer mold, but when bonding to the encapsulation surface, the curing time is shortened and cured to improve the bonding strength. It is also good to reduce the degree. For example, if an epoxy resin is used for both the sealing resin and the adhesive, if the degree of curing of the sealing resin is reduced, the unreacted groups of the sealing resin (epoxy resin) become The adhesive strength is stronger than the resin.

The temperature at the time of bonding is preferably set to 115 ° C. or less from the viewpoint of suppressing deformation of the card frame. When a thermosetting resin is used as the adhesive for the adhesive layer, it is necessary to perform a curing treatment.In this case, however, the temperature is set to 150 ° C. or less to suppress the deformation of the card frame. (Preferably below 130 ° C) is recommended.

In the semiconductor storage card of the present invention, the separation between the semiconductor mounting substrate and the card frame is highly suppressed even under the bending stress by introducing the stress relaxation layer. Even if such a stress relaxation layer is extremely thin, the above-mentioned effect can be sufficiently ensured, so that it is possible to meet the demand for miniaturization and thinning of a semiconductor built-in card. Example

Hereinafter, the present invention will be described in detail based on examples. However, the following embodiments do not limit the present invention, and all modifications and alterations that do not depart from the gist of the above and below are included in the technical scope of the present invention.

Note that the expanded porous PTFE finolem (“Goatex (registered trademark)” manufactured by Jiannon Gotex), which is used in the following Examples, Comparative Examples, and Reference Examples, has a reduced water repellency. No processing has been performed.

The evaluation methods used in the following Examples, Comparative Examples, and Reference Examples are as follows.

Measure the tensile modulus and tensile rupture elongation of the stress-relaxed layer 刖 laminated with the adhesive film. The measurement was performed using a tensile tester manufactured by Toyo Seiki Co., Ltd.

R ◦ GRAPH—R3 ”, according to the provisions of JISK7113, sample shape: strip shape (1 O mm X l 2 O mm), distance between chucks: -70-mm, Measurement temperature Temperature, tensile speed .. 2 mmm 1 n Calculated tensile elasticity Strain: 0-1 mm to 1 mm, row 5

Tensile modulus of the adhesive film that forms the adhesive layer>

The tensile modulus of the adhesive film before lamination with the stress relaxation layer was measured in the same manner as in the case of the _bπ self-stress relaxation layer. However, if the adhesive layer contains epoxy resin, cure at 120 ° C for 90 minutes before measuring.

Using a compression tester (“STROGRAPH—R3” manufactured by Toyo Seiki Co., Ltd.), place the card with the built-in semiconductor card on the semiconductor mounting board side down. A three-point bending load is applied so that the indenter contacts a polycarbonate plate (described later) viewed from the bottom. At this time, the sample is set so that the semiconductor substrate is at the center between the fulcrums of the support. Read the maximum load when the substrate comes off as the bending peel strength. Also, measure the stroke at break (the distance the indenter has moved from the time the indenter came into contact with the sample and applied a load to the time it broke). The measurement is performed in accordance with JIS K 6856, under the conditions of indenter tip: R 1 mm, distance between support points: 20 mm, measurement temperature: normal temperature, compression speed: 1 mm / min. . Also check which part of the built-in semiconductor card is the peeled surface after peeling.

Glue resin

Metallic microscope with dimensions measurement function (Olinno. STM-U

Using M J), measure the flow dimension of the adhesive resin protruding from the semiconductor mounting board (microscope magnification: 100 ×). Measure the maximum value in each of the four sides, and take the average value as resin resin (β m) o

(1) Peeling strength between semiconductor mounting board (sealing surface) and adhesive film

As a semiconductor mounting board, its model is 0.2 mm thick.

FR4 glass epoxy substrate ("EL-170" manufactured by Mitsubishi Gas Chemical Company) on each test example · Comparative example • Compression molding of the same resin as the sealing resin used in the reference example Thickness 1 Use a 0 mm plate (model plate) o On the other hand, as the adhesive film, use each experimental example, comparative example, or

,

In the reference example, the adhesive film (1) laminated with the stress relaxation layer is used. A release polyester film was placed on one side of this adhesive finolem (however, if the adhesive finolem was produced by the cast method, the release polyester film used in the cast method was used as it was. Use), A copper foil with a thickness of 35 μπι is placed on the other surface, and these are pressed using a roll laminator at a temperature of 100 ° C and a pressure of 1 MPa. This crimped body was cut to a width of 10 mm, and the release film was peeled off. The sealing surface side of the model plate was pressed using a press at a temperature of 120 ° C and a pressure of 0 • 5 Bond under the conditions of MPa and time of 10 seconds to prepare a measurement sample. At this time, a thickness of 2 between the adhesive film and the model plate

Insert a 5 μm FEP film (release film) to a position 50 mm from the end face. The part where the release film is inserted is not bonded, so it will be a chucking part when measuring peel strength. The copper foil is used as a reinforcing material for preventing the adhesive film from elongating when measuring the peel strength.

Measure the peel strength by peeling the adhesive finolem together with the copper foil in the direction of 90 degrees from the model board in accordance with JIS C 6481. .

(2) Peeling strength of card frame and adhesive film Instead of a model plate, a polycarbonate plate with a thickness of 1 • 0 mm (similar to Sumitomo Dow's ΓGaliper 310-1) 0 ”) is used. Others are the same as above (1) Semiconductor mounting board (sealing surface) 'and peeling strength of adhesive film.

Example 1

Epoxy resin (“EPICLON” manufactured by Dainippon Ink and Chemicals, Inc.

5 5 ": Bisphenol II type) and phenol / lenopollac resin (hardening agent," TD-21993 "manufactured by Dainippon Ink & Chemicals, Inc.) and the equivalent ratio of reactive functional groups to epoxy groups Then, 0.12 parts by mass of a curing accelerator (2-ethyl-4-methylimidazole) was added to 100 parts by mass of the mixture. MEK is added to the obtained composition, and the concentration of components other than MEK is added. There were prepared 3 8 mass ^_0/0 solution (varnish).

The viscosity of the above varnish was measured using a viscometer (“RE100L” manufactured by Toki Sangyo Co., Ltd.) at a sample volume of 1 mL and a temperature of 23 ° C. Yes, use a gelling tester (“Nichishin Kagaku Co., Ltd.“ 0-Choice 0-3 ”).]” Temperature of hot plate: 170 ° C according to the provisions of 13C6487 The gel time measured under the following conditions was 240 seconds.

Stretched porous p TFE film (“Gotex (registered trademark)” manufactured by Japan Goatex, thickness: 20 μηι, porosity: 70%, maximum pore size: 0.2 the zm), impregnated with the varnish using a kiss roll coater, 1 5 0 ° to 5 minutes and dried in C, and the volume filling ratio of the pores is 1 0 0 vol ⁰ /. (64% by mass) of an adhesive film (adhesive layer) was obtained.

Stretched porous PTFE film ("Gotex (registered trademark)", manufactured by Japan Gortex Co., Ltd.), thickness: 80111, porosity: 35 ° /., Maximum pore diameter: 0 as a stress relaxation layer 1 μm) with the above adhesive film on both sides, using a roll laminator, pressure bonding at a temperature of 100 ° C and a pressure of 1 MPa to form a 3-layer adhesive. A laminated film was obtained.

A silicon chip (thickness: 0 mm) viewed from the flash memory on the surface of an FR 4 glass epoxy circuit board ("EL-170" manufactured by Mitsubishi Gas Chemical Company) with a terminal circuit on the back. 4mm, width: 7mm, length: 10) mounted and sealed with epoxy resin compound (outer dimensions: thickness: 1.5mm, width: 10mm, length The above adhesive laminated film cut to the same size as the substrate was placed on a sealing surface (length: 15 mm) (the surface opposite to the terminal surface) using a press machine at a temperature of 110 °. C, pressure: 0.5 MPa, time: 5 seconds, preliminarily bonded to obtain a substrate with an adhesive laminated film. Next, the poly carb seen on the card frame With the adhesive laminated film in the center of a net plate ("Gulliver 301-1-10" manufactured by Sumitomo Dow) (thickness: 1.0 mm, width: 20 mm, length: 30 mm) The substrate is bonded with the adhesive film exposed side to the polycarbonate plate side using a press machine under the following conditions: temperature: 120 ° C, pressure: 0.5 MPa, and time: 10 seconds. Then, the substrate was cured at 120 ° C. for 90 minutes to obtain a semiconductor built-in card. The above-described evaluation was performed on the above-mentioned expanded porous PTFE film and the semiconductor built-in card. Table 1 shows the results.

Example 2

The expanded porous PTF Efinolem that constitutes the stress relaxation layer has a thickness of 8

0 μm, porosity: 65%, maximum pore diameter: 0 • 2 im Example 1 was changed to that of Example 1 except that it was changed to that of Jiannon Gotex Co., Ltd. Similarly, a semiconductor built-in power was obtained. The above-mentioned evaluation of the above-mentioned stretched porous PTFE film and semiconductor built-in force

Ρ 4

The price was done. The results are shown in Table 1.

Example 3

The expanded porous PTFE finolem that constitutes the stress relaxation layer has a thickness of 8 μm-and a void of: -85. The largest pore-diameter: 5 •-0 μ-m. Except for changing to “Gotechx (registered trademark)” manufactured by Ksu Co., Ltd.), the built-in semiconductor power was obtained in the same manner as in Example 1. The above-described evaluation was performed on the above-mentioned stretched porous PTFE film and the semiconductor built-in force. The results are shown in Table 1.

Example 4

Urethane resin (Rixon Pond U α-111

A)) 100 parts by mass and epoxy resin (D 「CΝ 4

3 8 — EK 85 JJ) 32 parts by mass were blended, and MEK was added to the resulting mixture to prepare a 65% by weight solution (poured). This peni And the viscosity measured in the same manner as in Example 1 was 330 centipoise.

This varnish is applied to the surface of a PET film (release film, thickness: 50 μm) to a thickness of 20 μπι using a die coater, and then applied to a surface of 150 °. After drying at C for 5 minutes, an adhesive film was obtained.

Only one of the adhesive layers (adhesive film) of the adhesive laminated film was changed to the urethane resin adhesive film obtained by the above casting method, and the stress was further reduced. A card with a built-in semiconductor was obtained in the same manner as in Example 1 except that the expanded porous PTFE film constituting the layer was the same as that used in Example 2. The adhesive layer made of the urethane adhesive film was on the card frame side. The above-described evaluation was performed on the above-mentioned stretched porous PTFE film and the card with a built-in semiconductor. The results are shown in Table 1.

Example 5

Toluene was added to a saturated polyester resin (“Hybon 766 3” manufactured by Hitachi Chemical Co., Ltd.) to prepare a 60% by mass solution (varnish). The viscosity of this varnish measured in the same manner as in Example 1 was as follows: Viscosity: -36-0 cm-voise. -Apply this varnish to the surface of a PET film (release film, thickness: 50 μm) using a die coater to a thickness of 20 / xm. It was dried at 150 ° C. for 5 minutes to obtain an adhesive film. Only one of the adhesive layers of the adhesive laminated film is changed to a polyester-based adhesive film obtained by the above-mentioned casting method, and further, an expanded porous PTFE film constituting a stress relaxation layer A card with a built-in semiconductor was obtained in the same manner as in Example 1, except that the same as that used in Example 2 was used. The adhesive layer made of the polyester adhesive film was on the card frame side. The above expanded porous PTFE film, and The above-mentioned evaluation was performed on the semiconductor and the semiconductor built-in card. Table 1 shows the results.

Comparative Example 1

MEK was added to the same composition as that used for the varnish in Example 1 to prepare a solution (varnish) having a concentration of 65% by mass of components other than the MEK. The viscosity and the gel time of this varnish measured in the same manner as in Example 1 were as follows: viscosity: 380 cmvoise; gel time: 230 seconds.

This varnish is applied to the surface of a PET film (release film, thickness: 50 μπι) by a casting method to a thickness of 120 μππι using a die coater. 1 5 0 dried 1 0 minutes ^D C, to obtain an adhesive Fi Noremu.

A card with a built-in semiconductor was obtained in the same manner as in Example 1, except that the adhesive film peeled from the release film was used instead of the adhesive laminated film having a stress relaxation layer. The above-described evaluation was performed on the semiconductor built-in card. The results are shown in Table 1.

Example 6

The stress-relaxation-layer-stretched porous P T-FE film is composed of:-one thickness-:-80 / im, porosity: 20%, maximum pore size: 0.05 A card with a built-in semiconductor was obtained in the same manner as in Example 1 except that it was changed to μπι (“GATEX (registered trademark)” manufactured by Japan Gotex). The above-described evaluation was performed on the above-mentioned stretched porous PTFE film and the semiconductor built-in card. The results are shown in Table 1.

Reference example 1

The stretched porous PTFE film that constitutes the stress relaxation layer has a thickness of 80 μm, a porosity of 96%, and a maximum pore diameter of 10 // m (“Gotex (registered trademark)” manufactured by Japan Goretex. Change to ")") and glue

Three Tried to make a flexible laminated film, but when bonding the adhesive film to the stress relaxation layer (stretched porous PTFE film), the stress relaxation layer (stretched porous PTFE film) was crushed between the rolls. As a result, the thickness could not be maintained sufficiently, so fabrication of a semiconductor built-in card using this was discontinued.

Example 7

A card with a built-in semiconductor was obtained in the same manner as in Example 2, except that the thickness of the adhesive film used in Example 2 was changed to 30 μm. The above-described evaluation was performed on the above-mentioned stretched porous PTFE film and the semiconductor built-in card. The results are shown in Table 1.

Example 8

Only one of the adhesive layers of the adhesive laminate film was changed to a polyester-based adhesive film (same as in Example 5, except that the thickness was 50 ^ m), and the stress was further increased. A card with a built-in semiconductor was obtained in the same manner as in Example 1, except that the expanded porous PTFE film constituting the relaxation layer was the same as that used in Example 2. The adhesive layer made of the polyester-based adhesive film was on the card frame side. With respect to the stretched porous PFE-film and the semiconductor built-in force, the above-mentioned evaluation was performed. The results are shown in Table 1.

Comparative Example 2

A polyester adhesive film was produced in the same manner as in Example 5, except that the thickness was set to 120 μπι. A semiconductor built-in force was obtained in the same manner as in Example 1 except that the above-mentioned polyester-based adhesive film peeled from the release film was used in place of the above-mentioned adhesive laminated film having a stress relaxation layer. . The above-described evaluation was performed on the semiconductor built-in card. Table 1 shows the results. IN3

O en

The number in parentheses on the peeled surface indicates the type of peeled surface in the case of fe-bonding.

The column of peeling surface in Table 1 shows where the peeling occurred in the semiconductor built-in force after measuring the bending peeling strength. The term “adhesive interface” means the interface between the adhesive layer (adhesive film) and the semiconductor mounting substrate, and the interface between the force and the frame.

As can be seen from Table 1, the built-in semiconductor card in which the stress relaxation layer is interposed between the semiconductor mounting board and the frame (Examples 1 to 8) has no stress relaxation layer. As compared with the semiconductor wafers (Comparative Examples 1 and 2), the flexural peel strength is higher, and it can be confirmed that the effect of suppressing the peeling between the semiconductor mounting board and the frame is exhibited. Also, the adhesive resin flow has become smaller. In particular, an adhesive layer having a stress relaxation layer of an expanded porous PTFE film having both favorable values of tensile elastic modulus and elongation at break, and a product of tensile elastic modulus and thickness being suitable is used. In the semiconductor built-in force of Examples 1 to 5 and 8 formed on the 1K frame side, the bending peel strength was very good, and the above peeling suppressing effect was remarkable. Industrial applicability

The semiconductor built-in card of the present invention can be used for a conventionally known application as a memory card or an IC card.

Claims

1. Substrate with semiconductor mounted on it

A semiconductor built-in card characterized in that a stress relaxation layer is interposed between the substrate and the card frame.

2. The semiconductor built-in force according to claim 1, wherein the stress relaxation layer comprises a resin finolem force.

3. The tensile elastic modulus of the resin film that constitutes the stress relaxation layer is

3. The card with a built-in semiconductor according to claim 1, wherein the card has a value of 1 to 130 MPa and a tensile elongation at break of 5% or more.

Enclosure

4. The stress relaxation layer has a porous structure.

2. The card with a built-in semiconductor according to 1.

5. The resin film constituting the stress relaxation layer has a thickness of 0.0.

3. The built-in semiconductor power source according to claim 2, wherein the force is from 0.5 to 0.5 mm.

6. The card with a built-in semiconductor according to claim 1, wherein the stress relaxation layer is made of expanded porous polytetrafluoroethylene.

7. The card with a built-in semiconductor according to claim 6, wherein the porosity of the stretched porous-porous polytetrafluoroethylene-ethylene-nolem is 30 to 95%.

8. An adhesive layer A is interposed between the stress relieving layer and the substrate, and an adhesive layer B is interposed between the stress relieving layer and the card frame. The card with a built-in semiconductor according to claim 1, wherein the stress relaxation layer is fixed to the substrate and the card frame by io.

9. The peel strength at the interface between the substrate and the adhesive layer A and the peel strength at the interface between the card frame and the adhesive layer B are each at least 0.0 NZ mm. Built-in semiconductor power described One do.

10. The card with a built-in semiconductor according to claim 8, wherein the adhesive layer A and the adhesive layer B are made of mutually different adhesives.

11. The card with a built-in semiconductor according to claim 8, wherein the adhesive constituting the adhesive layer A is a thermosetting resin.

12. The card with a built-in semiconductor according to claim 11, wherein the thermosetting adhesive is an epoxy resin.

1 3. The card with a built-in semiconductor according to claim 8, wherein the adhesive constituting the adhesive layer B is a thermoplastic resin.

14. The card with a built-in semiconductor according to claim 13, wherein the thermoplastic resin is a polyester resin.

1 5. The card with a built-in semiconductor according to claim 8, wherein the product of the tensile modulus and the thickness of the adhesive layer B is 50 MPa * mm or less.

1 9. The card with a built-in semiconductor according to claim 8, wherein the adhesive layer A and the adhesive layer B are formed by filling the pores of an expanded porous polytetrafluoroethylene film with an adhesive.