JP2006134266A - Memory card and method for manufacturing memory card - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a memory card having sufficient strength and high quality. <P>SOLUTION: The memory card 20 has a substrate 20 in which at least a semiconductor memory element 21 is mounted on a component mounting surface 20a and a card edge shape connection terminal 23 is provided on a rear surface 20b opposite to the component mounting surface 20a, a first case 12 which protects the component mounting surface 20a of the substrate 20 and a second case 13 which protects the rear surface 20b of the substrate 20. Then, it is characterized in that the first case 12 is formed by resin molding the whole component mounting surface 20a of the substrate 20 and the second case 13 is formed by resin molding the rear surface 20b of the substrate 20 except the connection terminal 23. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a memory card, and more particularly to a memory card having a memory function used as an expansion module of a recording / reproducing apparatus such as a host device and a method for manufacturing the memory card.

  2. Description of the Related Art Conventionally, as a recording / reproducing apparatus such as a personal computer or a digital still camera or an external storage device of an information processing apparatus, there is a substantially strip-shaped memory card using a semiconductor memory as a recording medium. Some of these memory cards are used for various purposes with substantially the same outer shape. For example, memory cards include those for storing image data taken with a digital still camera or the like. In this memory card, it is desired that the memory card be miniaturized in accordance with miniaturization and performance improvement of the host device, and at the same time, physical strength is also desired.

  Conventionally, these memory cards have a structure in which a wiring board on which electronic components such as a semiconductor memory are mounted is sandwiched between a pair of outer casings made of resin or metal. It is manufactured by welding or bonding a wiring board. As a method for manufacturing the memory card, various methods for manufacturing a memory card have been proposed for the purpose of reducing the thickness and improving the manufacturing yield (for example, see Patent Document 1).

JP 2003-44804 A

  By the way, in the conventional memory card manufacturing method described above, a clearance is required between the outer casing and the electronic component mounted on the wiring board, and the outer dimensions are increased. Further, in this memory card, the strength is lowered due to the clearance between the outer casing and the wiring board, and the strength is further reduced when the outer casing is thinned to reduce the thickness of the memory card. Further, since the wiring board is sandwiched and formed by the pair of outer casings, the accuracy of the thickness of the entire memory card is low and the positional accuracy of the wiring board with respect to the outer casing is also low.

  The present invention has been proposed in view of such a conventional situation, a memory card that can be thinned while maintaining sufficient strength, improved accuracy such as the thickness of the memory card, and improved manufacturing yield. An object is to provide a method for manufacturing a memory card.

  In order to achieve the above-described object, a memory card according to the present invention includes a substantially rectangular substrate having at least a semiconductor memory mounted on a component mounting surface, and a first housing that protects the component mounting surface of the substrate. And a second housing for protecting the substrate. Then, after forming the first casing, the second casing is molded, and the first casing is formed by resin molding the entire component mounting surface of the substrate, and the second casing is formed. The body is formed by resin-molding a back surface facing the component mounting surface of the substrate and a peripheral end portion of the substrate.

  The first casing may be formed from a thermosetting resin, and the second casing may be formed from a thermoplastic resin.

  Furthermore, the first casing may be formed by resin compression molding, and the second casing may be formed by resin injection molding.

  Further, the substrate may have a card edge type connection terminal on the back surface, and the second housing may protect the back surface of the substrate excluding the connection terminal.

  Further, the substrate may be provided with a convex portion that adjusts the length shape of the substrate by crushing at the opposite end of the substrate where the connection terminal is provided.

  Furthermore, a positioning pin that determines the formation position of the second housing may be provided on the back surface of the substrate.

  Furthermore, in the method for manufacturing a memory card according to the present invention, at least a semiconductor memory is mounted on a component mounting surface, and a substantially rectangular board component in which a card edge connection terminal is provided on the back surface opposite to the component mounting surface. A first casing forming step of resin-molding a first casing that protects the mounting surface, and a second casing excluding the connection terminal on the back surface of the substrate after the first casing forming step. A second casing forming step of resin molding.

  In the memory card according to the present invention, at least a semiconductor memory is mounted on a component mounting surface, and a first housing is directly mounted on a substantially rectangular substrate having a card edge connection terminal on the back surface opposite to the component mounting surface. Since the body and the second casing are formed by resin molding, the number of processing steps can be reduced and the body can be manufactured at low cost.

  Further, the present invention can make use of the respective resin characteristics by forming the first casing and the second casing with different resins, and even when the memory card is made thin, Strength can be maintained.

  In addition, the present invention is a high quality product in which the first housing that protects the component mounting surface is compression-molded using a thermosetting resin, so that no side pressure is applied to the mounted electrical component such as a semiconductor memory. Memory cards can be manufactured.

  Furthermore, according to the present invention, by providing a convex portion that adjusts the length shape of the substrate by crushing, the positional accuracy of the first and second housings with respect to the substrate is improved, and the product yield is improved. Can do.

  Hereinafter, specific embodiments of the memory card 10 to which the present invention is applied will be described in detail with reference to the drawings. It should be noted that the present invention is not limited to the embodiments described below, and various modifications can be made without departing from the scope of the present invention.

  As shown in FIGS. 1 and 2, a memory card 10 according to the present invention includes a substantially rectangular plate-shaped card body 11 that is resin-molded. As shown in FIG. 2, the card body 11 is composed of a first housing 12 and a second housing 13, and a substrate 20 (FIG. 3) is built therein.

  As shown in FIGS. 3A to 3C, the board 20 is a substantially rectangular plate-like printed wiring board built in the card body 11. As shown in FIG. 3A, the substrate 20 is a flash having a large storage capacity of 4 megabytes (hereinafter simply referred to as MB) or more, for example, 16 MB, 32 MB, 64 MB, 128 MB, 256 MB, on the component mounting surface 20a. A semiconductor memory element 21 such as a memory, and a control circuit element 22 having a control circuit unit configured to control writing of data to the semiconductor memory element 21 and reading of data stored in the semiconductor memory element 21 are mounted. Yes.

  As shown in FIG. 3C, the board 20 has a memory card 1 and an external device (on the side face 20c on the short side of the board 20) on the back face 20b that is the face facing the component mounting face 20a. (Not shown) are connected in a card edge shape, for example, a connection terminal 23 comprising 10 electrodes provided in the short side direction is provided. Further, as shown in FIGS. 3A and 3C, the substrate 20 is provided with a notch 24 at a substantially central portion on the other side surface 20 d side of the substrate 20. A protrusion 25 formed in a mountain shape is provided on the bottom 24a. In addition, the substrate 20 is provided with through-holes 26 used for alignment of the substrate 20 when the first and second casings 12 and 13 are molded in the vicinity of the four corners of the rectangular shape excluding the connection terminals 23.

  The protrusions 25 are convex portions formed in a mountain shape at two locations of the bottom 24a of the notch 24 formed on the side 20d opposite to the side 20c on which the connection terminal 23 of the substrate 20 is provided, The height is slightly larger than the distance between the bottom 24a of the notch 24 and the side surface 20d. The protrusion 25 is formed on the side where the connection terminal 23 is provided by crushing the protrusion 25 in a direction parallel to the long side of the substrate 20 with a mold when forming the first casing 12 described later. The position of the side surface 20c with respect to the first housing 12 can be adjusted.

  The semiconductor memory element 21 having a volume capacity larger than that of the control circuit element 22 is provided with connection terminals 23 in order to reduce the amount of resin at the time of resin sealing, reduce molding shrinkage, and consequently suppress the warpage of the substrate 20. It is preferable to provide on the side 20c side.

  In addition, the protrusion 25 is not limited to the mountain shape as described above, and may have a size that can be crushed by a mold in order to align the first housing 12 during molding. For example, it may be a strip.

  As shown in FIGS. 4A to 4D, the first housing 12 seals the semiconductor memory element 21 and the control circuit element 22 mounted on the substrate 20 on the component mounting surface 20 a of the substrate 20. It is formed in the size to be. Specifically, the first housing 12 is formed over substantially the entire component mounting surface 20 a and seals the semiconductor memory element 21 and the control circuit element 22. The first housing 12 is formed from a thermosetting resin having toughness such as an epoxy resin. In addition, as shown in FIG. 4D, the first casing 12 is also sealed with resin at the peripheral surface of the through hole 26 of the substrate 20 and the vicinity of the through hole 26 on the back surface 20b side. A seat shape is formed on the back surface 26, and a positioning hole 27 is formed when the second casing 13 is molded.

  As shown in FIGS. 5A to 5D, the second housing 13 includes the entire portion excluding the connection terminals 23 on the back surface 20 b of the substrate 20, and the first mounting surface 20 a from the peripheral end of the substrate 20. It is formed so that the rib area | region over the housing | casing 12 may be covered. The second housing 13 forms the remaining card body 11 other than a part of the card body 11 formed by the first housing 12. Specifically, the second housing 13 covers substantially the entire back surface 20b of the substrate 20, and the partition wall 23a provided so as to separate each electrode of the connection terminal 23 from each other, and the memory card 10 by the user. Ejecting from the chamfer 23b for easily discriminating the insertion direction into the external device, the drop-out preventing recess 23c for preventing the memory card 10 from dropping out when the memory card 10 is mounted on the external device, and the external device of the memory card 10 And a recess 23e that makes it easy for the user to attach / detach the memory card 10 to / from an external device. The second housing 13 is formed of a thermoplastic resin having high impact resistance such as polycarbonate.

  The second housing 13 is not limited to the chamfered portion 23b, the drop-off preventing recessed portion 23c, the ejected recessed portion 23d, and the recessed portion 23e described above, and may include any member. It may not be.

  Next, the manufacturing method of the memory card 10 described above will be described in detail with reference to FIG. First, the memory card 10 performs primary molding for forming the first housing 12 on the component mounting surface 20a of the substrate 20 on which the semiconductor memory element 21 and the control circuit element 22 are mounted. It is manufactured by performing secondary molding that forms the second housing 13 on the peripheral ends of 20b and the substrate 20.

  First, as shown in FIG. 6A, the substrate 20 on which the semiconductor memory element 21 and the control circuit element 22 are mounted is set in a primary molding die (not shown). At that time, the substrate 20 is sandwiched between molds (not shown) at the protrusions 25 on the side surfaces 20c and 20d, and the length of the long side of the substrate 20 is adjusted by crushing the protrusions 25. The position where the first housing is formed on the substrate 20 is adjusted.

  Next, as shown in FIG. 6B, as the first molding, the first housing 12 including the positioning holes 27 is formed by allowing a thermosetting resin to flow into a mold (not shown). . This primary molding maintains the mechanical strength of the mounting components such as the semiconductor memory element 21 to be sealed, and does not apply high pressure to the mounting components during molding, and can be accurately molded along the contours of the mold and the mounting components. Compression molding is performed.

  Next, the substrate 20 on which the first housing 12 is formed is set in a secondary molding die (not shown). At that time, the substrate 20 is sandwiched by using the positioning holes 27 formed at the time of the primary molding and the upper surface portion of the card body 11 formed at the time of the primary molding, so that the substrate 20 is accurately set at a desired position. . As the secondary molding, as shown in FIG. 6C, a second housing including the partition wall 23a and the peripheral end portion of the card body 11 is obtained by allowing a thermoplastic resin to flow into a mold (not shown). 13 is formed. In this secondary molding, an external shape is easily molded, and injection molding with high impact resistance is performed.

  Finally, as shown in FIG. 6D, the memory card 10 is finished by laser-printing predetermined information such as a model number, for example, at a predetermined position of the formed card body 11.

  As described above, the memory card 10 according to the present invention is formed by directly molding the first casing 12 and the second casing 13 on the substrate 20 by resin molding, so that the processing steps are reduced and the manufacturing is inexpensive. can do.

  Further, in the present invention, by forming the first housing 12 and the second housing 13 with different resins, the respective resin characteristics can be utilized, and even when the memory card 10 is thinned. The mechanical strength can be maintained.

  Further, according to the present invention, the first casing 12 that protects the component mounting surface 20a is compression-molded using a thermosetting resin, so that a side pressure is applied to the electrical component mounted such as the semiconductor memory element 21. Therefore, a high quality memory card 10 can be manufactured.

  In the present invention, since the positioning hole 27 is provided at the time of molding the first casing 12, secondary molding is performed using the positioning hole 27 and the upper surface portion of the card body 11 formed at the time of primary molding. Sometimes accurate positioning can be performed, and the memory card 10 with high accuracy can be manufactured.

  Further, the present invention is provided with the protrusion 25 that adjusts the length shape of the substrate 20 by crushing, thereby improving the positional accuracy of the first and second casings 12 and 13 with respect to the substrate 20, Yield can be improved.

  In addition, although this invention demonstrated embodiment applied to the memory card, you may apply not only to this but to an IC card.

It is the perspective view which looked at the memory card concerning the present invention from the upper surface side. It is the perspective view which looked at the memory card concerning the present invention from the bottom side. (A) is a top view of the board | substrate incorporated in the memory card based on this invention, (b) is a bottom view, (c) is a rear view. (A) is a top view of the board | substrate with which the 1st housing | casing of the memory card based on this invention was shape | molded, (b) is a bottom view, (c) is a rear view, (d ) Is a right side view. (A) is a top view of the board | substrate with which the 2nd housing | casing of the memory card based on this invention was shape | molded, (b) is a bottom view, (c) is a rear view, (d ) Is a left side view. (A) is a figure which shows the board | substrate with which the electrical component was mounted, (b) is a figure which shows a primary shaping | molding process, (c) is a figure which shows a secondary shaping | molding process, (d ) Is a diagram showing a printing process of predetermined information.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Memory card, 11 Card main body, 12 1st housing | casing, 13 2nd housing | casing, 20 Board | substrate, 20a Component mounting surface, 20b Back surface, 20c, 20d Short side, 21 Semiconductor memory element, 22 Control circuit element, 23 Connection terminal, 23a Partition wall, 24 Notch, 24a Bottom, 25 Protrusion, 26 Through hole, 27 Positioning hole

Claims (10)

A substantially rectangular substrate having at least a semiconductor memory mounted on a component mounting surface;
A first housing protecting the component mounting surface of the board;
A second housing for protecting the substrate,
The second casing is molded after the first casing is molded, and the first casing is formed by resin-molding the entire component mounting surface of the substrate. A memory card formed by resin-molding a back surface of the substrate facing the component mounting surface and a peripheral edge of the substrate.   2. The memory card according to claim 1, wherein the first casing is made of a thermosetting resin, and the second casing is made of a thermoplastic resin.   The memory card according to claim 2, wherein the first casing is formed by resin compression molding, and the second casing is formed by resin injection molding.   2. The memory card according to claim 1, wherein the substrate has a card edge type connection terminal on the back surface, and the second casing protects the back surface of the substrate excluding the connection terminal.   The said board | substrate is provided with the convex part which adjusts the length shape of the said board | substrate by crushing in the said board | substrate edge part on the opposite side to which the said connection terminal of the said board | substrate was provided. Memory card.   2. The memory card according to claim 1, wherein a positioning pin for determining a formation position of the second casing is provided on the back surface of the substrate. Resin molding a first housing that protects a component mounting surface of a substantially rectangular substrate having at least a semiconductor memory mounted on the component mounting surface and a card edge connection terminal provided on the back surface opposite to the component mounting surface A first housing forming step,
A method for manufacturing a memory card, comprising: a second housing forming step of resin-molding a second housing except for the connection terminals on the back surface of the substrate after the first housing forming step.   In the first housing forming step, the length shape of the substrate is adjusted by crushing using a convex portion provided on the substrate end on the opposite side of the substrate where the connection terminal is provided. 8. The method of manufacturing a memory card according to claim 7, further comprising a length adjusting step.   8. The memory according to claim 7, wherein the first housing forming step further includes a pin forming step of forming positioning pins for determining a forming position of the second housing on the back surface of the substrate. Card manufacturing method.   10. The method of manufacturing a memory card according to claim 9, wherein the second housing forming step forms the second housing using the positioning pins formed by the pin forming step.

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