JP2008021033A - Electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component which is high in strength reliability. <P>SOLUTION: A memory card 200 is provided with: an electronic circuit 201; a reinforcement board 202; and a top case 203. The reinforcement board 202 is arranged to face the electronic circuit 201, and bonded and fixed to the electronic circuit 201. The top case 203 is arranged to face the reinforcement board 202 at the opposite side of the electronic circuit 201, and bonded and fixed to the reinforcement board 202. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electronic component, and more particularly to an electronic component having a reinforcing member.

Memory cards are commercially available from various companies under various trade names. Memory cards have been recognized by the market for being lightweight, thin, and small, and combined with the increase in memory capacity, they are used in various applications. At present, the memory card is widely used as a memory medium used in a portable information terminal device such as a digital still camera, a notebook computer, a mobile phone, a video camera, and an electronic reading terminal. In particular, the memory card is often provided in a portable electronic device, and further reduction in thickness and size of the memory card itself is essential in product development.
However, as the thickness and size of the memory card are reduced, the strength of the memory card is reduced, and problems such as damage to a built-in memory chip (IC chip) due to an external load and peeling of a solder mounting portion have occurred. Various proposals for improving the strength of the memory card have been made for this problem.
For example, a technique is known in which a metal reinforcing plate is inserted into the top and bottom of a memory card and resin-molded (see, for example, Patent Document 1). The purpose of this technique is to improve the strength of the memory card by using such a structure, to suppress the damage of the IC chip due to an external load, and to improve the connection reliability of the solder mounting portion.
JP-A-1-42295

However, the technique disclosed in Patent Document 1 is effective when the IC chip is small relative to the reinforcing plate as shown in FIG. When the chip becomes large, the stress applied to the IC chip from the external load increases accordingly, and it is necessary to devise how to attach the reinforcing plate. Specifically, in the technique disclosed in Patent Document 1, a sufficient adhesive material is not introduced between the reinforcing plate and the exterior, and therefore, the adhesive interface between the reinforcing plate and the exterior, or between the reinforcing plate and the IC chip. When the resin does not enter the adhesion interface, slipping occurs at each adhesion interface, resulting in a significant loss of the effect of the reinforcing plate. In particular, in a memory card having a volume of 1/10 or less of an SD card, such as a microSD card, the degree of freedom in component mounting design is low, and a sufficient space for inserting an iron plate cannot be secured. Only thick reinforcing plates can be inserted. For this reason, it is necessary to devise a position for inserting the reinforcing plate, a position for bonding the reinforcing plate and other components, and a method for securely bonding the reinforcing plate and other components by a resin mold or the like at the bonding position. Become.
In this regard, it is difficult for the technique of Patent Document 1 to expect a sufficient effect, particularly in an ultra-thin and ultra-small product such as microSD.
In addition to the memory card, when electronic components are generally required to be downsized, there are similar requirements as described above.

  Accordingly, an object of the present invention is to solve such problems and provide an electronic component having high strength reliability.

An electronic component as a first invention includes an electronic circuit, a reinforcing member, and a housing. The reinforcing member is disposed so as to face the electronic circuit, and is bonded and fixed to the electronic circuit. The housing is disposed opposite to the reinforcing member on the side opposite to the electronic circuit, and is bonded and fixed to the reinforcing member.
In the present invention, since the reinforcing member is sandwiched and bonded between the electronic circuit and the housing, the electronic circuit, the reinforcing member, and the housing are integrally fixed via an adhesive. For this reason, even if a force such as bending is applied to the electronic component, the force is distributed and applied to the electronic circuit, the reinforcing member, and the casing, so that the electronic circuit can be prevented from being damaged. In addition, when the electronic circuit is soldered to a substrate or the like, it is possible to suppress the peeling of the solder.
As described above, according to the present invention, it is possible to provide an electronic component with high strength reliability.
In the electronic component as the second invention, the adhesive fixing between the electronic circuit and the reinforcing member and the adhesive fixing between the reinforcing member and the housing may be performed by a resin mold.
In the electronic component as the third invention, the reinforcing member may be formed with a recess that is recessed more than the other part on at least one of the adhesion surface with the electronic circuit and the adhesion surface with the housing.
In the present invention, the electronic component, the reinforcing member, and the case can be efficiently bonded. That is, since the reinforcing member has a recess, the fluidity of the adhesive between the members to be bonded is improved, and the adhesive between the members to be bonded can easily enter. As a result, the electronic circuit, the reinforcing member, and the housing can be fixed together more reliably. In particular, when the adhesive fixing is performed by a resin mold, it is possible to perform the bonding more reliably by improving the fluidity of the adhesive (resin).

In the electronic component as the fourth invention, a convex portion having a shape corresponding to the concave portion may be formed at a position corresponding to the concave portion on the surface opposite to the bonding surface where the concave portion is formed.
In the present invention, since the convex portion is formed, it is possible to secure a gap for the adhesive to enter between the reinforcing member and the member on the side where the convex portion protrudes, and more reliably perform the bonding. Is possible.
In the electronic component as the fifth invention, the concave portion may be continuously formed from the outer edge portion of the reinforcing member to a position corresponding to the central portion of the electronic circuit.
In the present invention, the adhesive can be easily penetrated to the central portion of the electronic circuit, and the bonding can be more reliably performed.
In the electronic component as the sixth invention, the recess may be formed along the longitudinal direction of the electronic circuit or the longitudinal direction of the housing.
According to the present invention, it is possible to provide an electronic component with higher strength reliability against bending applied to both ends in the longitudinal direction.
In the electronic component as the seventh invention, the recess may be constituted by a plurality of intersecting grooves.

In the present invention, it is possible to provide an electronic component with higher strength and reliability against twisting.
In the electronic component as the eighth invention, the predetermined dimension of the reinforcing member may be larger than the predetermined dimension of the electronic circuit.
In the present invention, it is possible to arrange and fix the reinforcing member so as to cover the electronic circuit, and it is possible to prevent peeling (solder peeling or peeling of the adhesive state) from occurring at the end of the electronic circuit.
In the electronic component as the ninth aspect of the invention, the reinforcing member has a corner portion disposed opposite to at least one corner portion of the electronic circuit, and the corner portion of the reinforcing member is more than the corner portion of the electronic circuit. May also extend outward.
In the present invention, it is possible to arrange and fix the reinforcing member so as to cover the corner of the electronic circuit, and it is possible to prevent peeling (solder peeling or peeling of the adhesive state) from the corner of the electronic circuit. .
In the electronic component as the tenth invention, an inward cutout may be formed on at least one side of the reinforcing member.

In the present invention, the electronic component, the reinforcing member, and the case can be efficiently bonded. That is, since the reinforcing member has a notch, the fluidity of the adhesive between the members to be bonded is improved, and the adhesive can easily enter between the members to be bonded. As a result, the electronic circuit, the reinforcing member, and the housing can be fixed together more reliably. In particular, when the adhesive fixing is performed by a resin mold, it is possible to perform the bonding more reliably by improving the fluidity of the adhesive (resin).
In the electronic component as the eleventh invention, the notch may be formed at a position corresponding to the central portion of one side of the electronic circuit.
In the present invention, the adhesive can be easily penetrated in the central portion of the electronic circuit, and the bonding can be performed more reliably.
In the electronic component as the twelfth invention, the notch may extend inward from one side of the electronic circuit.
In this invention, since the notch is formed toward the inner side rather than one side of the electronic circuit, the adhesive easily enters the electronic circuit from the reinforcing member side.
In the electronic component as the thirteenth invention, the reinforcing member may be formed with at least one through hole penetrating in the thickness direction.

In the present invention, the electronic component, the reinforcing member, and the case can be efficiently bonded. That is, since the reinforcing member has a through hole, the fluidity of the adhesive between the members to be bonded is improved, and the adhesive between the members to be bonded can easily enter. As a result, the electronic circuit, the reinforcing member, and the housing can be fixed together more reliably. In particular, when the adhesive fixing is performed by a resin mold, it is possible to perform the bonding more reliably by improving the fluidity of the adhesive (resin).
In the electronic component as the fourteenth aspect, the through hole may be formed at a position facing the electronic circuit.
In the present invention, since the through hole is formed at a position facing the electronic circuit, the adhesive can surely enter the electronic circuit from the reinforcing member side.
In the electronic component as the fifteenth invention, the through hole may be formed at a position facing the central portion of the electronic circuit.
In the present invention, the adhesive can surely enter the central portion of the electronic circuit.
In the electronic component as the sixteenth invention, at least a part of the reinforcing member may be bent with respect to the adhesive surface with the electronic circuit or the adhesive surface with the housing.

In the present invention, since a part of the reinforcing member is bent, the reinforcing effect against bending and twisting is improved.
In the electronic component as the seventeenth invention, the electronic component may be a memory card.

  According to the present invention, it is possible to provide an electronic component with high strength reliability.

An embodiment according to the present invention will be described with reference to FIGS. In addition, the same code | symbol is provided to the component with the same function by description of a figure, and the description is abbreviate | omitted.
(Embodiment 1)
A memory card (electronic component) according to Embodiment 1 of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional configuration diagram showing a bonding structure of a reinforcing plate of a memory card. The memory card 200 has a top case 203 disposed on the upper side as an exterior and a bottom case 206 disposed on the lower side, and an electronic circuit 201 is mounted on the substrate 204 by a conductor 205 therein. A module 208 is provided. As a material of the top case 203 and the bottom case 206, resin, metal, or the like is used. As the electronic circuit 201, a microprocessor, a CSP (chip size package), a semiconductor flash memory chip, or the like is used. As the conductor 205, solder, conductive resin, or the like is used. As the substrate 204, a glass epoxy substrate, a ceramic substrate, or the like is used.
In the bonding structure of the present invention, the reinforcing plate 202 is bonded to the module 208 (on the top case 203 side) via an adhesive 207. Further, the reinforcing plate 202 and the electronic circuit 201 and the reinforcing plate 202 and the top case 203 are bonded with an adhesive 207. Note that the material of the reinforcing plate 202 may be fiber reinforced plastic, or metal such as stainless steel, copper, aluminum, magnesium alloy, or zinc alloy, and a material having higher rigidity than the adhesive 207 is used.

With the above configuration, slippage does not occur at the interface between the electronic circuit 201 and the reinforcing plate 202 and between the top case 203 and the reinforcing plate 202, and the electronic circuit 201, the reinforcing plate 202, and the top case 203 are integrated. As a result, the stress applied to the electronic circuit 201 alone by an external force can be distributed to the reinforcing plate 202 and the top case 203, and the stress concentration on the electronic circuit 201 can be reduced.
Note that the adhesive 207 may be filled by resin molding. If bonded by resin molding, the side surfaces of the reinforcing plate 202 are also bonded together, and the reinforcing effect becomes stronger.
With the configuration as described above, the reinforcing effect by the reinforcing plate 202 can be further strengthened, and is particularly effective for reinforcing thin devices.
When the adhesion of the reinforcing plate 202 by resin molding is examined, in order to realize this structure, the resin flow during molding is improved, and the reinforcing plate 202 and the electronic circuit 201 and between the reinforcing plate 202 and the top case are improved. It is preferable that the resin flows more efficiently between the two. The shape of the reinforcing plate in consideration of such resin flow will be described in the following embodiment.

(Embodiment 2)
A memory card according to Embodiment 2 of the present invention will be described with reference to FIGS. 2 and 3, (a) is an external view of a reinforcing plate, and (b) is a cross-sectional configuration diagram showing an adhesive structure of the reinforcing plate.
In the memory card 300 shown in FIG. 2, as shown in FIG. 2A, the reinforcing plate 301 is provided with grooves 302 on both sides. The groove 302 may be provided only on one side.
When resin molding is performed when the reinforcing plate 301 is bonded, the resin 305 is filled along the grooves 302. Therefore, the resin is surely filled between the groove 302, the top case 303 facing the groove 302, and the electronic circuit 304, and a stable bonding area can be secured. In particular, as shown in FIG. 2B, the resin 305 can enter along the groove 302 even when there is only a sufficient thickness to dispose the reinforcing plate 301 between the top case 303 and the electronic circuit 304. Therefore, stable adhesion becomes possible.
In addition, from the viewpoint that the resin 305 easily enters, the groove 302 is preferably provided by vertically cutting (crossing) the opposite sides from the end of the reinforcing plate 301. On the other hand, from the viewpoint that the entire electronic circuit 304 can be integrated with the reinforcing plate 301, it is preferable that the groove 302 is provided at a position facing the center of the electronic circuit 304 in the reinforcing plate 301.

Further, the groove shape may be a shape as shown in FIG.
In FIG. 3A, the reinforcing plate 311 is provided with a groove 312 on one side. A convex portion 317 is formed on the back surface of the groove 312 so as to protrude in a shape corresponding to the groove 312. Also in this structure, as shown in the cross-sectional configuration diagram of FIG. 3B, a certain amount of resin can be filled between the top case 313 and the reinforcing plate 311 and between the electronic circuit 314 and the reinforcing plate 311. It is possible to secure a bonding area.
The groove 312 is preferably formed along the longitudinal direction 316 of the electronic circuit 314 and the longitudinal direction of the memory card 310. In general, a portion that tends to be damaged when an external force is applied to the memory card 310 is near the center in the longitudinal direction of the electronic circuit 314 or near the center in the longitudinal direction of the memory card 310. For this reason, if the grooves 312 are formed along these longitudinal directions, the same effect as the case where ribs are formed on the memory card 310 (hereinafter referred to as rib reinforcing effect) can be obtained. The reinforcing effect can be increased when an external force is applied to bend.
Further, the groove shape may be a shape as shown in FIG.
As shown in FIG. 4A, the reinforcing plate 318 may be provided with a plurality of intersecting (orthogonal) grooves 319 in a direction inclined by 45 degrees with respect to the reinforcing plate 318. The groove 319 is preferably formed so as to open to the outer periphery of the reinforcing plate 318. In this case, even when the electronic component (memory card) on which the reinforcing plate 318 is disposed is particularly vulnerable to bending and twisting, the reinforcing plate 318 makes anisotropy in the 45-degree direction as in the fiber orientation theory of the composite material. It is possible to obtain a rib reinforcing effect by providing the. As a result, it is possible to obtain a reinforcing effect for both the twisting of the reinforcing plate 318 as shown in FIG. 4B and the bending of the reinforcing plate 318 as shown in FIG. 4C. Furthermore, the reinforcing plate 318 and a member (an electronic circuit or an exterior case) bonded to face the reinforcing plate 318 can be integrated and bonded. In FIG. 4A, as an example in which the most reinforcing effect is obtained, a plurality of grooves 319 intersecting (orthogonal) in a direction inclined by 45 degrees with respect to the reinforcing plate 318 are provided. A plurality of grooves may be crossed so as to be line symmetric. That is, the same effect can be obtained without necessarily crossing in a direction inclined by 45 degrees.

Example 1 of the above embodiment will be described with reference to FIGS. 5 and 6, Example 2 will be described with reference to FIG. 7, and Example 3 will be described with reference to FIG.
(Example 1)
Example 1 of a microSD card using the reinforcing plate of Embodiments 1 and 2 according to the present invention will be described with reference to FIGS.
FIG. 5A shows a schematic diagram of the microSD card with the top case removed. In the microSD card 328, a semiconductor memory chip 322 and a CSP 323 are solder-mounted on a glass epoxy substrate 321. FIG. 5B is a schematic diagram when bending is applied to the microSD card 328.
When the microSD card 328 is supported by the support portions 324 at both ends and a load is applied to the central portion 325, a high stress is generated in the central portion 326 of the semiconductor memory chip 322, and the load becomes about 3 kgf. It came. This is a case where a general three-point bending test is performed, and there is a high possibility that an external force is applied to the longitudinal direction 327 of the microSD card 328 as shown in FIG. On the other hand, it needs to be hardened.
In Example 1, a microSD card 330 was created as shown in FIG. FIG. 6A is an external view of a reinforcing plate 331 as Example 1, and the material is made of stainless steel (SUS304). The reinforcing plate 331 is formed with three grooves 332 that are parallel along the long side direction. A convex portion 329 that rises corresponding to the groove 332 is formed on the back side portion of the groove 332, and serves as a rib extending in the longitudinal direction of the reinforcing plate 331. The short side of the reinforcing plate 331 is 7.6 mm, the long side is 10.2 mm, and the thickness is 50 μm.

FIG. 6B is a diagram in which the reinforcing plate 331 is arranged on the microSD card 330. In FIG. 6B, the top case 336 and the bottom case 337 (see FIG. 6C) serving as the exterior are not shown. In the microSD card 330, a silicon semiconductor memory chip (semiconductor flash memory) 333 and a microcomputer 335 are arranged on a substrate 334. The reinforcing plate 331 is positioned so as to face the semiconductor memory chip 333, and further, a top case 336 is placed thereon, and then the resin 338 is filled and cured. FIG. 6C is a cross-sectional configuration diagram after the resin 338 is cured.
By using the reinforcing plate 331 of the present invention, the semiconductor memory chip 333 and the reinforcing plate 331 are bonded via an adhesive (resin 338). Further, a certain gap is secured between the top case 336 and the reinforcing plate 331 by the convex portion 329 which is a protrusion on the back surface side of the groove 332 formed in the reinforcing plate 331, and the resin 338 enters the gap. As a result, the top case 336, the reinforcing plate 331, and the semiconductor memory chip 333 are bonded together.
With the above configuration, the microSD card in which the planar reinforcing plate having the same thickness as the reinforcing plate 331 is arranged has a load resistance of 4 kgf, whereas the microSD card 330 of the present invention improves the load resistance to 5 kgf. . Thereby, in this invention, it becomes possible to suppress damage to the semiconductor memory chip 333 or the like.

(Example 2)
Next, Example 2 of the microSD card using the reinforcing plate of Embodiments 1 and 2 according to the present invention will be described with reference to FIG.
FIG. 7A is an external view of the reinforcing plate 341 of the present invention. Similar to the first embodiment, the reinforcing plate 341 has a short side of 7.6 mm, a long side of 10.2 mm, a thickness of 50 μm, and a material of stainless steel (SUS304). Further, the reinforcing plate 341 is formed with two grooves 342 extending from each end to the opposite sides and intersecting the cross. On the back side portion of the groove 342, a raised portion 339 is formed corresponding to the shape of the groove 342, and this raised portion 339 also crosses the cross.
FIG. 7B is a diagram in which the reinforcing plate 341 is arranged on the microSD card 340. In FIG. 7B, the top case 349 and the bottom case 348 (see FIG. 7C) serving as the exterior are not shown. In the microSD card 340, a semiconductor memory chip 344 and a CSP 345 are mounted on a substrate 343, and a reinforcing plate 341 is bonded to face the semiconductor memory chip 344. Specifically, the reinforcing plate 341 is positioned so as to face the semiconductor memory chip 344, and further, a top case 349 is covered thereon, and then the resin 346 is filled and cured. FIG. 7C is a cross-sectional configuration diagram of the resin 346 after curing.

Also in this embodiment, adhesion is performed by resin filling. For this reason, the resin penetrates into the portion of the groove 342 and good adhesion between the reinforcing plate 341 and the semiconductor memory chip 344 facing the groove 342 becomes possible. Further, since the convex portion 339 is formed on the back side of the groove 342, a certain gap can be secured between the top case 349 and the reinforcing plate 341, and the reinforcing plate can be obtained by filling the gap with resin. Thus, it is possible to securely bond the semiconductor memory chip 344 and the top case 349 to each other. As a result, the semiconductor memory chip 344, the reinforcing plate 341, and the top case 349 are integrally bonded via the resin.
In addition, by increasing the cross-sectional area of the groove 342 at the end of the reinforcing plate 341 and decreasing it at the center of the reinforcing plate 341, the cross-sectional area of the groove 342 is continuously changed, and the resin is applied using the capillary phenomenon. You may permeate to the center part of the reinforcing plate 341.
With the above configuration, the microSD card in which the planar reinforcing plate having the same thickness as the reinforcing plate 341 is disposed has a load resistance of 4 kgf, whereas the microSD card 340 of the present invention improves the load resistance to 5 kgf. . Thereby, in this invention, it becomes possible to suppress damage to the semiconductor memory chip 344 and the like.

(Example 3)
Next, Example 3 of the microSD card using the reinforcing plate of Embodiment 1 according to the present invention will be described with reference to FIG.
FIG. 8A is an external view of the reinforcing plate 351 of the present invention. The reinforcing plate 351 has a short side of 5.5 mm, a long side of 10.2 mm, a thickness of 50 μm, and is made of stainless steel (SUS304). The reinforcing plate 351 is a plate with a return 352 attached when the reinforcing plate 351 is punched.
FIG. 8B is a diagram in which a reinforcing plate 351 is arranged in a housing formed by the top case 359 and the bottom case 358 of the microSD card 350. As shown in FIG. 8B, by directing the return 352 of the reinforcing plate 351 upward (on the side opposite to the semiconductor memory chip 354), a certain gap can be secured between the top case 359 and the resin 356. Becomes easier to flow. Further, the return 352 is provided on both sides (for example, both long sides) of the reinforcing plate 351 facing each other, and the width (for example, the width in the short side direction) of the reinforcing plate 351 including the return 352 is disposed to face the reinforcing plate 351. By making the width smaller than the width of the memory chip 354, as shown in FIG. 8C, the resin also enters between the vicinity of the edge of the semiconductor memory chip 354 and the return 352 of the reinforcing plate 351 due to capillary action. The memory chip 354, the reinforcing plate 351, and the outer case (top case 359) can be integrated.

With the above configuration, the microSD card having the flat reinforcing plate having the same thickness as the reinforcing plate 351 has a load resistance of 4 kgf, whereas the microSD card 350 of the present invention has a load resistance of up to 4.5 kgf. improves. Thereby, in this invention, it becomes possible to suppress damage to the semiconductor memory chip 354 and the like.
(Embodiment 3)
A memory card according to Embodiment 3 of the present invention will be described with reference to FIGS.
In the memory card 410 illustrated in FIG. 9A, an electronic circuit 412 is mounted on a substrate 411. Further, the reinforcing plate 414 of the present invention is bonded onto the electronic circuit 412. The outer shape of the reinforcing plate 414 is larger than the outer shape of the electronic circuit 412 facing it.
With such a configuration, it becomes possible to increase the load resistance against the external load at the end of the electronic circuit 412, and the connection portion between the electronic circuit 412 and the substrate 411 is peeled off from the external load. Can be suppressed.
Note that, as in the reinforcing plate 415 shown in FIG. 9 (b), a configuration in which the outer shape of the reinforcing plate 415 is enlarged only at a portion corresponding to at least the corner of the electronic circuit 412 is also effective and resin in resin filling. It is possible to further improve the fluidity.

Further, as long as the reinforcing plate can cover only the portion corresponding to at least the corner of the electronic circuit 412 as in the memory card 420 shown in FIGS. 10A and 10B, any other shape can be used. It may be something like this.
For example, as shown in FIG. 10A, a notch may be provided in the area 422 of the reinforcing plate 421 corresponding to the central portion of the electronic circuit 412. In such a structure, the central portion of the electronic circuit 412 can be securely bonded to the reinforcing plate 421. That is, in the reinforcing plate 421, the resin fluidity near the center of the electronic circuit 412 is improved, and the exterior (not shown) disposed on both surfaces of the reinforcing plate 421 and the electronic circuit 412 can be securely bonded. It becomes. As a result, the exterior case, the reinforcing plate 421, and the electronic circuit 412 can be integrated with each other through the resin.
Further, the shape of the reinforcing plate as shown in FIG. 10B is also effective. The reinforcing plate 424 in FIG. 10B has substantially the same shape as the reinforcing plate 421 shown in FIG. 10A, but the size of the notch formed is different. Specifically, the notch formed in the area 425 of the reinforcing plate 424 is formed to extend inward from the outer shape of the electronic circuit 412, and when the electronic circuit 412 and the reinforcing plate 424 are disposed to face each other, the electronic circuit A part of 412 is exposed to the reinforcing plate 424 side.

With this configuration, when the electronic circuit 412 and the reinforcing plate 424 are bonded with the resin 432, the resin 432 flows as indicated by the arrow 431 in FIG. Can be reliably filled. As a result, the resin 432 is filled in a shape as shown in FIG. 11B, and the electronic circuit 412, the reinforcing plate 424, and the exterior case (not shown) can be bonded together.
As shown in FIG. 12, it is also preferable that a through hole 441 is formed in the reinforcing plate 424. The through hole 441 is preferably sufficiently small with respect to the reinforcing plate 424, has a size that does not affect the strength of the reinforcing plate 424, and is provided at a position facing the vicinity of the central portion of the electronic circuit 412.
With such a configuration, the resin flows and enters the through hole 441 of the reinforcing plate 424 so that the electronic circuit 412 and the reinforcing plate 424 can be bonded. Such a configuration is effective not only when the resin is filled with a resin mold by injection molding or the like, but also when the resin is applied to the upper portion of the reinforcing plate 424 and the outer case is covered to perform the adhesion. is there. In this case, due to the capillary phenomenon, the resin permeates between the electronic circuit 412 and the reinforcing plate 424 and between the reinforcing plate 424 and the exterior case (not shown), and the electronic circuit 412, the reinforcing plate 424, and the exterior case. Can be integrally bonded.

Example 4 of the above embodiment will be described below.
Example 4
Example 4 of a microSD card using the reinforcing plate of Embodiment 3 according to the present invention will be described with reference to FIG.
Fig.13 (a) is an external view of the reinforcement board 511 of this invention. The reinforcing plate 511 has a short side of 5.5 mm, a long side of 10.2 mm, a thickness of 50 μm, and is made of stainless steel (SUS304). Further, the reinforcing plate 511 is formed so that the corner portion covers the corner portion of the semiconductor memory chip 514 disposed so as to face the corner portion. That is, the corners of the reinforcing plate 511 are formed so as to extend outward from the corners of the semiconductor memory chip 514 facing each other. Further, a groove 523 is formed in the central portion of the reinforcing plate 511 along the longitudinal direction of the reinforcing plate 511. The reinforcing plate 511 is arranged such that its longitudinal direction coincides with the longitudinal direction of the semiconductor memory chip 514 or the longitudinal direction of the microSD card 500. Further, a raised convex portion 509 is formed on the back side of the groove 523. Furthermore, a through hole 512 that penetrates the thickness direction of the reinforcing plate 511 is formed at the center in the longitudinal direction of the groove 523. The formation position of the through hole 512 substantially coincides with the position corresponding to the central portion of the semiconductor memory chip 514 when the reinforcing plate 511 is disposed on the microSD card 500. Furthermore, through holes 513 having a smaller diameter than the through holes 512 are formed in the reinforcing plate 511 at positions facing the four corners of the semiconductor memory chip 514. Further, a notch 521 formed inward is provided at the center of each side of the reinforcing plate 511. The cutout 521 formed on the long side is formed to the inside of the outer shape of the semiconductor memory chip 514.

FIG. 13B is a diagram in which the reinforcing plate 511 is arranged on the microSD card 500. In FIG. 13B, the top case 517 and the bottom case 518 (see FIG. 13C) serving as the exterior are not shown. In the microSD card 500, a semiconductor memory chip 514 and a CSP (chip size package) 516 are mounted on a substrate 515. The reinforcing plate 511 is bonded onto the semiconductor memory chip 514, and the notch 521 of the reinforcing plate 511 is disposed so as to reach the inside from the outer edge of the semiconductor memory chip 514. In the adhesion between the reinforcing plate 511 and the semiconductor memory chip 514, the reinforcing plate 511 is positioned so as to face the semiconductor memory chip 514. After the structure shown in FIG. 13B is assembled, the assembled body is attached to the bottom case 518. The adhesive 510 was applied onto the reinforcing plate 511, and the top case 517 was placed thereon to cure the adhesive 510. FIG. 13C is a cross-sectional configuration diagram of the adhesive 510 after being cured.
In this configuration, the adhesive 510 spreads in the outer case due to a capillary phenomenon of a gap formed between the reinforcing member 511 and the opposing member, and the semiconductor memory chip 514, the reinforcing plate 511, and the top case 517 are bonded to the adhesive 510. It is bonded together through.
With the above configuration, the microSD card having the flat reinforcing plate having the same thickness as the reinforcing plate 511 has a load resistance of 4 kgf, whereas the microSD card 500 of the present invention improves the load resistance to 5 kgf. . Thereby, in this invention, it becomes possible to prevent damage to the semiconductor memory chip 514 and the like.

(Embodiment 4)
A memory card according to Embodiment 4 of the present invention will be described with reference to FIG.
In a memory card 610 shown in FIG. 14A, an electronic circuit 612 is mounted on a substrate 614. The memory card 610 has a shape that is long in the Z-axis direction in the three-dimensional coordinate system in the figure. Furthermore, the substrate 614 and the electronic circuit 612 disposed in the memory card 610 also have a shape that is long in the Z-axis direction.
In the memory card 610, the reinforcing plate 611 of the present invention is disposed so as to cover the electronic circuit 612. The outer shape of the reinforcing plate 611 is larger than the outer shape of the electronic circuit 612, and has a shape that encloses the upper part and the side part of the electronic circuit 612. Both ends of the reinforcing plate 611 in the X-axis direction are bent downward in the Y-axis direction so as to form a plane parallel to the YZ plane.
Even if the reinforcing plate 611 is placed in the memory card 610 and cured with an adhesive, both ends in the Z-axis direction are fixed and bent in the Y-axis direction. 612 can be prevented from being damaged and the mounting portion from being peeled off. In particular, a product having an elongated outer shape is required to have a load resistance against such bending, but the reinforcing plate 611 of the present invention improves the load resistance against such bending.

FIG. 14B is an external view of the memory card 610 as seen from the Y axis direction positive side. As shown in FIG. 14B, the outer shape of the reinforcing plate 611 is larger than the outer shape of the electronic circuit 612, and the reinforcing plate 611 is formed so as to cover the corners of the electronic circuit 612 from the Y-axis direction. ing. The electronic circuit 612 is housed in the internal space of the reinforcing plate 611 formed by bending the reinforcing plate 611.
FIG. 14C shows a cross-sectional configuration diagram after bonding the reinforcing plate 611, the electronic circuit 612, and the substrate 614. As shown in FIG. 14C, the bent portion 618, which is a bent portion of the reinforcing plate 611, is in contact with the substrate 614 and formed so as to provide a gap between the reinforcing plate 611 and the electronic circuit 612. Yes.
The bent portion 618 is a portion that is difficult to bend even when both ends in the Z-axis direction are fixed and bent in the Y-axis direction, and the electronic circuit 612 disposed inside the reinforcing plate 611 is damaged or the mounting portion is peeled off. Is unlikely to occur. Further, since the bent portion 618 is formed so as to contact the substrate 614, the length of the bent portion 618 in the Y-axis direction is adjusted, and the distance between the electronic circuit 612 and the reinforcing plate 611, and the reinforcing plate 611 and the top. The distance from the case 616 can be adjusted, and a space for the resin 615 to enter can be secured.

Example 5 of the above embodiment will be described with reference to FIG.
(Example 5)
Example 5 of a microSD card using the reinforcing plate of Embodiment 4 according to the present invention will be described with reference to FIG.
FIG. 15A is a schematic diagram showing a state in which the top case of the microSD card is removed. In the microSD card 710, a semiconductor memory chip 712 and a microcomputer 715 are solder mounted on a glass epoxy substrate 716. Further, a reinforcing plate 711 is disposed to face the semiconductor memory chip 712.
The reinforcing plate 711 is curved in the XY plane in the three-dimensional coordinate system in the drawing, and is in contact with the semiconductor memory chip 712 at both ends in the X-axis direction. The reinforcing plate 711 has a short side of 5.5 mm, a long side of 10.2 mm, and a thickness of 50 μm.
FIG. 15B is an external view of the microSD card 710 as viewed from the Y axis direction positive side. As shown in FIG. 15B, the outer shape of the reinforcing plate 711 is larger than the outer shape of the semiconductor memory chip 712, and the reinforcing plate 711 is disposed so as to cover the semiconductor memory chip 712 from the Y-axis direction. Yes.

FIG. 15C shows a cross-sectional configuration diagram after bonding the reinforcing plate 711, the semiconductor memory chip 712, and the substrate 716. The reinforcing plate 711 is in contact with the semiconductor memory chip 712 in the area 713 at both ends in the X-axis direction. Therefore, as described with reference to FIG. 14, a sufficient space for the adhesive to enter between the reinforcing plate 711 and the semiconductor memory chip 712 and between the reinforcing plate 711 and the top case 714 should be secured. Can do. As a result, the top case 714, the reinforcing plate 711, and the semiconductor memory chip 712 can be integrally bonded via the adhesive.
With the above configuration, the microSD card having a flat reinforcing plate having the same thickness as the reinforcing plate 711 has a load resistance of 4 kgf, whereas the microSD card 710 of the present invention has a load resistance of up to 4.5 kgf. improves. As a result, in the present invention, it is possible to prevent damage to the semiconductor memory chip 712 and the like.
(Other)
The configurations described in the above embodiments can be adopted not only for microSD cards but also for various electronic components. However, it is particularly effective to employ the configuration of the present invention in a microSD card that is ultra-thin and that has almost no arrangement margin for members in the thickness direction inside the exterior. This is because the microSD card has almost no gap between the members, and the conventional reinforcing plate cannot secure a space for the adhesive to enter between the reinforcing plate and the opposing member. This is because the adhesive can enter by providing the reinforcing plate with irregularities or providing through holes.

Adhesion is preferably performed by resin molding. However, when a through hole or the like is provided in the reinforcing plate, it is possible to infiltrate the adhesive by capillary action.
With the configuration as described above, the rigidity of the microSD card can be improved.

  The present invention can be applied to memory cards such as SD cards, miniSD cards, microSD cards, P2 cards, memory sticks, multimedia cards, smart media, and compact flash (registered trademark).

Schematic showing the memory card of Embodiment 1 of the present invention Schematic which shows the memory card of Embodiment 2 of this invention. Schematic which shows the memory card of Embodiment 2 of this invention. Schematic which shows the reinforcement board of Embodiment 2 of this invention. Explanatory drawing about the load resistance test of microSD card 1 is a schematic diagram of a microSD card according to a first embodiment of the present invention. Schematic diagram of a microSD card according to a second embodiment of the present invention. Schematic of the microSD card of Example 3 of the present invention Schematic which shows the memory card of Embodiment 3 of this invention. Schematic which shows the memory card of Embodiment 3 of this invention. Explanatory drawing explaining resin flow at the time of adhesion Schematic which shows the memory card of Embodiment 3 of this invention. Schematic of the microSD card of Example 4 of the present invention Schematic which shows the memory card of Embodiment 4 of this invention. Schematic diagram of a microSD card according to a fifth embodiment of the present invention. Cross-sectional configuration diagram of a conventional memory card

Explanation of symbols

200 Memory Card 201 Electronic Circuit 202 Reinforcing Plate 203 Top Case 204 Substrate 205 Conductor 206 Bottom Case 207 Adhesive 208 Module

Claims (17)

Electronic circuit,
A reinforcing member disposed opposite to the electronic circuit and bonded and fixed to the electronic circuit;
A housing that is arranged opposite to the reinforcing member on the opposite side of the electronic circuit, and that is bonded and fixed to the reinforcing member;
Comprising
Electronic components The adhesive fixing between the electronic circuit and the reinforcing member and the adhesive fixing between the reinforcing member and the housing are performed by a resin mold.
The electronic component according to claim 1. In the reinforcing member, a concave portion that is recessed from other portions is formed on at least one of an adhesive surface with the electronic circuit or an adhesive surface with the housing.
The electronic component according to claim 1 or 2. A convex portion having a shape corresponding to the concave portion is formed at a position corresponding to the concave portion on the surface opposite to the bonding surface where the concave portion is formed.
The electronic component according to claim 3. The concave portion is continuously formed from the outer edge portion of the reinforcing member to a position corresponding to the central portion of the electronic circuit.
The electronic component according to claim 3 or 4. The recess is formed along the longitudinal direction of the electronic circuit or the longitudinal direction of the housing.
The electronic component of any one of Claims 3-5. The recess is constituted by a plurality of intersecting grooves,
The electronic component of any one of Claims 3-5. A predetermined dimension of the reinforcing member is larger than a predetermined dimension of the electronic circuit;
The electronic component of any one of Claims 1-7. The reinforcing member has a corner portion disposed opposite to at least one corner portion of the electronic circuit,
The corner of the reinforcing member extends outward from the corner of the electronic circuit.
The electronic component of any one of Claims 1-8. A cutout toward the inside is formed on at least one side of the reinforcing member,
The electronic component of any one of Claims 1-9. The notch is formed at a position corresponding to a central portion of one side of the electronic circuit.
The electronic component according to claim 10. The cutout extends inward from one side of the electronic circuit,
The electronic component according to claim 10 or 11. The reinforcing member is formed with at least one through-hole penetrating in the thickness direction.
The electronic component of any one of Claims 1-12. The through hole is formed at a position facing the electronic circuit.
The electronic component according to claim 13. The through hole is formed at a position facing the center of the electronic circuit.
The electronic component according to claim 14. At least a part of the reinforcing member is bent with respect to an adhesive surface with the electronic circuit or an adhesive surface with the housing.
The electronic component of any one of Claims 1-15. The electronic component is a memory card.
The electronic component of any one of Claims 1-16.

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