IC module board

Abstract

To provide an IC module substrate in which a difficulty does not occur even in a resin mold at a place where wire bonding is applied even if a deviation occurs at a boring position of a non-through hole.SOLUTION: In an IC module substrate for IC card having an RFID communication function, a bridge non-through hole 18 which penetrates a base material 10 and whose rear surface side is covered by bridge wiring 21 is formed in the vicinity of a second connection pad 15, the second connection pad is connected with the bridge wiring by wire bonding through the bridge non-through hole, and the peripheral edge of the bridge non-through hole is arranged so as to be in contact with two coils different in circulating of a loop coil 11, adjacent to each other, extending from the second connection pad and not a coil 19 of a portion that has not circle the loop coil yet.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an IC module substrate with RFID communication functions, which has an IC chip that combines contact communication functions and contactless communication functions, and which has a loop coil connected to the contactless communication terminal and a contact terminal connected to the contact communication terminal. [Background technology]

[0002] In an IC module substrate with RFID communication function, which has a loop coil connected to the non-contact communication terminal of an IC chip that combines contact communication function and contactless communication function, and a contact terminal connected to the contact communication terminal, the loop coil is generally mounted on the IC mounting surface side, and the contact terminal is mounted on the surface opposite the IC mounting surface, and each contact terminal and each contact communication terminal of the IC chip are electrically connected by wire bonding through non-through holes (see, for example, Patent Document 1).

[0003] In this case, the bonding pads provided at the outer end of the loop coil are generally in contact with the periphery of the non-through hole (Fig. 5(a)), or are positioned adjacent to the wiring pattern on the outermost periphery of the coil (Fig. 5(b)), as shown in Figure 5. The wiring pattern on the outermost periphery of the coil is designed to either be in contact with the periphery of the non-through hole, or to pass very close to the periphery of the non-through hole without passing through any other wiring patterns.

[0004] However, in the conventional configuration described above, if the bonding pad provided at the outer end of the loop coil is in contact with a non-through hole, and there is a deviation in the drilling position due to issues with the accuracy of the hole formation position using a drill, the wire bonding to the bonding pad cannot be positioned correctly using image recognition technology, which could result in a defect.

[0005] Furthermore, if the outermost wiring of the loop coil is arranged around the non-through hole so that the bonding pad does not come into contact with the drill hole, the bonding pad will be positioned further out (closer to the periphery) of the IC module substrate, which creates the problem of making it difficult to reinforce the wire-bonded area together with the IC chip using a resin mold or the like. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6090006 Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, an object of the present invention is to provide an IC module substrate in which bonding pads and non-through holes are arranged so that even if there is a deviation in the drilling position of the non-through holes, there is little difficulty in wire bonding to the bonding pads and there is no difficulty in resin molding at the wire-bonded locations. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides: One surface of a sheet-like substrate has an IC chip equipped with a contact communication terminal and a non-contact communication terminal, and a spiral loop coil; a contact terminal on the other surface of the substrate; the loop coil is connected to the non-contact communication terminal, The contact terminal is connected to the contact communication terminal. An IC module substrate for an IC card having an RFID communication function, a bridge wiring is further formed on the other surface so as to straddle the loop coil; a non-through hole is formed through the substrate, the other surface of which is covered by either the contact terminal or the bridge wiring; The loop coil has a recessed region formed therein, the recessed region being partly recessed toward the center of the substrate, a first connection pad for bonding is provided at an end of the loop coil on the center side of the substrate, and a second connection pad is provided at an end of the loop coil on the outer side of the substrate; the second connection pad is provided in the recessed area; a bridge non-through hole is formed near the second connection pad, passing through the base material and having the other surface side covered by the bridge wiring; the contact terminal and the contact communication terminal are connected by wire bonding through the non-through hole; the first connection pad and the non-contact communication terminal are connected by wire bonding, and the second connection pad is connected to the bridge wiring by wire bonding through the bridge non-through hole; the bridge wiring and the non-contact communication terminal of the IC chip are connected by wire bonding through a non-through hole formed inside the loop coil, This is an IC module substrate characterized in that the periphery of the bridge non-through hole is arranged so as to contact a portion of two adjacent windings of the loop coil that have different windings and that are not yet wound around the loop coil and are not the portion of the winding that is directly connected to the second connection pad.

[0009] In the above IC module substrate, Among the windings in contact with the periphery of the bridge non-through hole, the outer winding is a winding extending from the second connection pad of the loop coil, and the outer periphery of the coil Still It may be a winding adjacent to a portion of the winding that is not completely round.

[0010] In the above IC module substrate, The bridge non-through hole may be disposed at a position offset to one side from the center line of the long side of the base material.

[0011] In the above IC module substrate, The second connection pad may be arranged outside the outermost winding of the windings that contact the periphery of the bridge non-through hole.

[0012] In the above IC module substrate, The tip of the second connection pad on the center side of the base material may be located closer to the center of the base material than the center of the bridge non-through hole.

[0013] In the above IC module substrate, The angle formed by the line segment connecting the center of the bridge non-through hole and the tip of the second connection pad on the center side of the base material and the line segment parallel to the long side of the module may be between 0° and 30°. [Effects of the Invention]

[0014] According to the IC module substrate of the present invention, in an IC module substrate mounted on an IC card or the like capable of contactless communication and contact communication, the position of the non-through hole connected to the connection pad at the outer end of the loop coil is adjusted to the IC module by a line and space for one turn of the coil. By forming the non-through hole at the center of the coil substrate, the wire bonding that connects the non-through hole to the connection pad formed at the outer end of the coil can be more reliably reinforced together with the IC chip using a resin mold or the like. [Brief explanation of the drawings]

[0015] [Figure 1] 1A and 1B are a plan view and a partially enlarged view of an embodiment of an IC module substrate of the present invention. [Figure 2] 1 is a plan perspective view of an IC module substrate according to an embodiment of the present invention, in a resin-molded state; [Figure 3] 1A and 1B are a side perspective view and a rear plan view showing an outline of an IC module substrate according to one embodiment of the present invention; [Figure 4] 10A and 10B are a plan view and a partially enlarged view of another embodiment of the IC module substrate of the present invention. [Figure 5] 1A and 1B are a plan view and a partially enlarged view of an example of a conventional IC module substrate. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments described below. Furthermore, in the embodiments shown below, technically preferable limitations are imposed for carrying out the invention, but these limitations are not essential requirements for the present invention. Furthermore, equivalent components may be designated by the same reference numerals, and their description may be omitted.

[0017] FIG. 1 shows a plan view and a partially enlarged view of one embodiment of an IC module substrate according to the present invention. The IC module substrate 1 includes a sheet-like substrate 10 made of a material such as glass epoxy and having a thickness of approximately 110 μm. A spiral loop coil 11 is formed on one surface (the surface shown in the figure, referred to as the front surface) of the substrate 10, wrapping around the periphery of the substrate 10. A portion of the loop coil 11 forms a recessed region 12 recessed toward the center of the substrate 10. A first connection pad 14 is formed at the end of the loop coil 11 closest to the center of the substrate 10, and a second connection pad 15 is formed at the end of the loop coil 11 on the outer side, serving as connection terminals for wire bonding. The loop coil 11 can be patterned by etching copper or aluminum foil using an etching resist pattern. The thickness of the loop coil 11 can be, for example, 5 μm to 50 μm. Unless otherwise specified, the term "connection" used herein refers to electrical connection.

[0018] A space for mounting an IC chip (not shown) is provided in the approximate center of the substrate 10, inside the loop coil 11. A plurality of non-through holes 13 are formed around the space for connecting the IC chip or loop coil 11 to connection terminals provided on the other surface (referred to as the back surface) of the substrate 10. The diameter of the non-through holes 13 may be, for example, 300 μm to 500 μm. Holes penetrating the substrate 10 are formed in the non-through holes 13, and the back surface of the non-through holes 13 is covered with contact terminals 20 or bridge wiring 21, as shown in FIG. 3(b). The contact terminals 20 are communication terminals for contact communication with external devices, and the bridge wiring 21 is formed to straddle the loop coil 11 on the back surface to connect the loop coil 11 to the IC chip or contact terminals 20.

[0019] That is, when viewed from the front surface side, the contact terminals 20 or bridge wiring 21 are exposed at the bottom of the non-through holes 13, and therefore the IC chip or loop coil 11 can be connected to the contact terminals 20 or bridge wiring 21 by wire bonding through the non-through holes 13. For wire bonding, a bonding wire made of gold or copper and having a diameter of about 10 μm to 40 μm can be used.

[0020] The second connection pad 15, which is the outer end of the loop coil 11, is formed at the tip of the winding that extends from the outermost periphery of the loop coil 11 into the recessed area 12. Here, the second connection pad 15 is referred to as the winding 19 extending from the second connection pad 15. Although the second connection pad 15 extends into the recessed region 12, it is located outside the overall winding pattern of the loop coil 11. The size and shape of the second connection pad 15 are not particularly limited as long as they have an area and shape that allow stable wire bonding. A bridge non-through hole 18 that penetrates the substrate 10 is formed near the second connection pad 15. The back side of the bridge non-through hole 18 is covered with a bridge wiring 21. Therefore, the second connection pad 15 and the bridge wiring 21 can be connected by wire bonding through the bridge non-through hole 18. The bridge non-through hole 18 is located approximately at the center of the long side of the IC module substrate 1 (the left-right direction in FIG. 1), but it may be located at a position offset to either side of the left-right center line.

[0021] As is clear from the enlarged view on the right side of FIG. 1 , in this embodiment, the bridge non-through hole 18 is located near the second connection pad 15 and toward the center of the substrate 10. The bridge non-through hole 18 is not located completely outside the winding pattern of the loop coil 11, but is located toward the outside of the winding pattern when the loop coil 11 is viewed as a whole. More specifically, the bridge non-through hole 18 is formed between the second connection pad 15 and a winding (referred to as winding A) 16 that runs adjacent to the winding 19 extending from the second connection pad 15 and the winding (referred to as winding B) 17 adjacent thereto on the inside, with winding A 16 and winding B 17 contacting the periphery of the bridge non-through hole 18. Therefore, when viewed from the second connection pad 15, the bridge non-through hole 18 is located inside the space between the windings and winding A 16.

[0022] In other words, since the second connection pad 15 is not in contact with the bridge non-through hole 18, even if there is a slight deviation in the drilling position when forming the bridge non-through hole 18 by drilling, the second connection pad 15 is not affected, and there is no problem in positioning the wire bonding to the second connection pad.

[0023] 2 is a plan perspective view of an IC chip 30 mounted on the IC module substrate 1 of Fig. 1, with contact communication terminals 31 and first connection pads 14 of the IC chip 30 connected to contact terminals 20 on the back side of the substrate 10 by wire bonding 32, and with second connection pads 15 connected to bridge wiring 21, and then resin-molded. The IC chip 30 can be one of a known configuration having both contact and non-contact communication functions.

[0024] The molding 33 is formed to a size that covers at least the IC chip 30, the wire bonding 32, the non-through hole 13, and the bridge non-through hole 18. Therefore, the IC chip 30, the wire bonding 32, etc. are embedded in the resin of the molding 33 and are protected from external impacts, etc. The molding resin used for the molding 33 can be appropriately selected from known resins.

[0025] 3(a) is a side perspective view showing an overview of the IC module substrate 1 molded as shown in FIG. 2, as seen from the direction of arrow A in FIG. 2. When forming the molding 33, the natural fluidity of the resin tends to result in a cross-sectional shape that is thick in the center and thin in the peripheral areas. As a result, the molding 33 covering the wire bonding 32 connecting the second connection pad 15 and the bridge wiring 21 tends to become thin in the area of ​​the bridge non-through hole 18 located on the outer side of the loop coil 11, which may result in insufficient protection of the wire bonding 32. To prevent this, the bridge non-through hole 18 and the second connection pad 15 should be formed closer to the center of the substrate 10.

[0026] The width and number of turns of the winding of the loop coil 11 are determined to achieve a predetermined communication performance, and are therefore difficult to change. In addition, the amount of recessed area 12 that extends toward the center is limited by the need for space in the center to mount IC chip 30. Therefore, in order to form bridge non-through holes 18 and second connection pads 15 closer to the center of the substrate 10, measures such as providing bridge non-through holes 18 in a more inward portion of the winding or devising a new shape for second connection pads 15 are necessary.

[0027] In contrast to this, in this embodiment, by arranging the bridge non-through holes 18 and second connection pads 15 as described above, whereas in the conventional example shown in FIG. 5 , the non-through holes corresponding to the bridge non-through holes 18 are formed at positions where the bonding pads corresponding to the second connection pads 15 contact the periphery, or where the outermost winding corresponding to winding A16 surrounds the periphery, the bridge non-through holes 18 can be formed inside the spaces between the windings and winding A16, and therefore can be formed closer to the center of the substrate 10.

[0028] That is, according to the IC module substrate 1 of this embodiment, the bridge non-through holes 18 in the recessed regions 12 of the loop coil 11 can be formed toward the center of the base material 10 of the IC module substrate 1 by a line and space equivalent to a maximum of one turn of coil winding, compared to the conventional configuration, and the area where the bridge non-through holes 18 and the second connection pads 15 are wire-bonded can be easily reinforced together with the IC chip 30 by using a resin mold or the like.

[0029] Figure 4 is a plan view and a partially enlarged view of another embodiment of the IC module substrate of the present invention. Description of the same parts of the IC module substrate 2 of this embodiment as those of the previously described embodiment will be omitted. As is clear from the enlarged view on the right side of Figure 4, in this embodiment, the bridge non-through hole 18 is formed between the winding A16 that winds around the second connection pad 15 adjacent to the winding B17 adjacent to the winding B17 on the inside thereof, and the windings A16 and B17 are in contact with the periphery of the bridge non-through hole 18, similar to the previously described embodiment.

[0030] Meanwhile, in the previously described embodiment, the second connection pads 15 were formed outside the bridge non-through holes 18, but in this embodiment, they are formed so that they extend toward the center to a position that is approximately aligned horizontally in the left-right direction of Figure 4, that is, so that their tips T are closer to the center of the substrate 10 than the centers of the bridge non-through holes 18. Furthermore, to match this arrangement, the winding patterns of winding A 16, winding B 17, and others, and the arrangement of the bridge non-through holes 18 have also been changed. As described above, the arrangement of the bridge non-through holes 18 may be offset to one side or the other from the left-right center line of the IC module substrate 2, so the arrangement can be changed as needed without affecting the extent to which the recessed regions 12 extend into the substrate.

[0031] 4, it is preferable that the position of the tip T of the second connection pad 15 relative to the bridge non-through hole 18 be such that the angle α formed by the line segment connecting the center of the bridge non-through hole 18 (indicated by an x ​​in the drawing) to the tip T of the second connection pad 15 and the line segment parallel to the long side of the IC module substrate 2 is between 0° and 30°. If the angle is made any larger, the arrangement of the inner windings may extend too far toward the center of the base material 10, causing the recessed area 12 to extend too far toward the center.

[0032] In this embodiment, by adopting the shape and arrangement of the bridge non-through holes 18 and the second connection pads 15 as described above, the bridge non-through holes 18 can be formed closer to the center of the substrate than in the conventional example, and the second connection pads 15 can also be formed closer to the center of the substrate 10.

[0033] That is, according to the IC module substrate 2 of this embodiment, the position of the tip T of the second connection pad 15 of the loop coil 11 is set to be equal to the position of the bridge non-through hole 18, as compared with the conventional configuration. Alternatively, it becomes possible to position the bridge non-through holes 18 closer to the center of the IC module substrate 2, and the bridge non-through holes 18 and the second connection pads 15 can be formed together closer to the center of the base material 10, making it easier to reinforce the areas where the bridge non-through holes 18 and the second connection pads 15 are wire-bonded together with the IC chip 30 using molding 33 or the like. [Explanation of symbols]

[0034] 1, 2...IC module board 10...Base material 11. Loop coil 12...Concave area 13. Non-through hole 14. First connection pad 15 Second connection pad 16. Winding A 17 Winding B 18···Bridge non-through hole 19. Winding extending from the second connection pad 20...Contact terminal 21. Bridge wiring 30 IC chip 31 Contact communication terminal 32. Wire bonding 33 Molding

Claims

1. One surface of a sheet-like substrate has an IC chip equipped with a contact communication terminal and a non-contact communication terminal, and a spiral loop coil; a contact terminal on the other surface of the substrate; the loop coil is connected to the non-contact communication terminal, The contact terminal is connected to the contact communication terminal. An IC module substrate for an IC card having an RFID communication function, a bridge wiring is further formed on the other surface so as to straddle the loop coil; a non-through hole is formed through the substrate, the other surface of which is covered by either the contact terminal or the bridge wiring; The loop coil has a recessed region formed therein, the recessed region being partly recessed toward the center of the substrate, a first connection pad for bonding is provided at an end of the loop coil on the center side of the substrate, and a second connection pad is provided at an end of the loop coil on the outer side of the substrate; the second connection pad is provided in the recessed area; a bridge non-through hole is formed near the second connection pad, passing through the base material and having the other surface side covered with the bridge wiring; the contact terminal and the contact communication terminal are connected by wire bonding through the non-through hole; the first connection pad and the non-contact communication terminal are connected by wire bonding, and the second connection pad is connected to the bridge wiring by wire bonding through the bridge non-through hole; the bridge wiring and the non-contact communication terminal of the IC chip are connected by wire bonding through a non-through hole formed inside the loop coil, An IC module substrate characterized in that the periphery of the bridge non-through hole is arranged so as to contact a portion of two adjacent windings of the loop coil that have different windings and that have not yet wound around the loop coil and are not the portion of the winding that is directly connected to the second connection pad.

2. 2. The IC module substrate according to claim 1, wherein, of the windings contacting the periphery of the bridge non-through hole, the outermost winding is a winding extending from the second connection pad of the loop coil and adjacent to a portion of the winding that has not yet completely wound around the outer periphery of the coil.

3. 3. The IC module substrate according to claim 1, wherein the bridge non-through holes are arranged at positions offset to one side from the center line of the long side of the IC module substrate.

4. 4. The IC module substrate according to claim 1, wherein the second connection pad is arranged outside the outermost winding of the loop coil that is in contact with the periphery of the bridge non-through hole.

5. 4. The IC module substrate according to claim 1, wherein the tip of the second connection pad on the center side of the substrate is positioned closer to the center of the substrate than the center of the bridge non-through hole.

6. 6. The IC module substrate according to claim 5, wherein an angle formed by a line segment connecting the center of the bridge non-through hole and the tip of the second connection pad on the center side of the substrate and a line segment parallel to a long side of the module is between 0° and 30°.

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