JP2007266268A - Thermocompression bonding jig, thermocompression bonding device, and board connecting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermocompression bonding jig capable of a connection between boards at a high reliability. <P>SOLUTION: The thermocompression bonding jig 20 has a thermocompression face for connecting a first board 100 having a first electrode 102 arranged laterally at a given interval, with a second board 200 having a second electrode 202 arranged laterally at a given interval. The thermocompression face comprises a plurality of first grooves provided based on a first interval with a given depth, and a plurality of second grooves which are provided perpendicular to the first grooves, and provided based on a second interval with a given depth. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thermocompression bonding jig, and more particularly to a thermocompression bonding jig capable of highly reliable inter-substrate connection.

  One method of bonding between substrates is a thermocompression bonding method. The thermocompression bonding method is a method in which a crimping jig is instantly warmed and the workpieces are melted and joined by the heat. Since heat is applied from the outside (ceramic heater chip), the basic principle is a technique close to soldering. Mainly suitable for joining resins, soldering flat cables, brazing metals, etc.

Conventional thermocompression bonding methods have had a problem that soldering defects are likely to occur because the portion to be crimped of the crimping jig has a flat surface. For example, Patent Document 1 proposes a crimping jig that forms a large number of grooves on the crimping surface (pressing surface) in order to solve this problem.
Japanese Patent Laid-Open No. 11-320088 (page 4, FIG. 3)

  The above-described proposal is to prevent the soldering failure by causing the molten flux adhering to the crimping surface to flow into the concave portion of the groove so as to maintain good heat conduction.

  On the other hand, a bonding method using FPC (Flexible Printed Circuit) and PWB (Printed Wired Bond) bonding materials using FPC (Flexible Printed Circuit) bonding, represented by ACF (Anisotropic Conductive Film) and ACP (Anisotropic Conductive Paste). In recent years, the number of electrodes tends to increase as the number of I / O signal lines increases. As a result, it is necessary to increase the thrust applied to the pressure bonding jig in order to secure a load (for example, 10 MPa or more) for pressure bonding per electrode in a flat surface pressure bonding jig used in the conventional thermocompression bonding method. Therefore, there is a problem that the required thrust force may not be ensured due to a problem in the specification of the thermocompression bonding apparatus.

  In addition, along with the reduction in size and size of electronic devices typified by portable information terminal devices, for example, bonding between substrates accommodated in the electronic device such as bonding of a module such as an HDD and an FPC or PWB is narrow. It has become. Therefore, the size of the thermocompression bonding jig used for the thermocompression bonding apparatus tends to be small.

  When the thermocompression bonding jig is reduced, the heat capacity given to the thermocompression bonding jig is also correspondingly reduced. For this reason, the temperature of the surface that directly contacts outside air such as the outer peripheral surface of the thermocompression bonding jig tends to decrease.

As a result, even in the same thermocompression bonding jig, for example, a temperature difference of 20 ° C. to 30 ° C. at the maximum can occur between the center and both ends. Therefore, this temperature difference causes a significant difference in the degree of plastic deformation of the FPC and the adhesive that is the joining member at the time of thermocompression bonding, which causes a problem of joining failure.

  Therefore, the present invention has been made to solve the above problems, and by forming the groove portion on the crimping surface in a predetermined form, a thermocompression bonding jig, a thermocompression bonding apparatus, and the like that are capable of highly reliable inter-board connection, An object of the present invention is to provide a substrate connection method.

  In order to achieve the above object, a thermocompression bonding jig according to the present invention includes a first substrate having first electrode portions arranged at a predetermined interval in the width direction, and the predetermined interval in the width direction. A thermocompression bonding jig having a crimping surface for connecting the second substrate having the arranged second electrode portions, wherein a plurality of the crimping surfaces are provided based on the first interval, A first groove portion having a predetermined depth and a second groove portion provided perpendicular to the first groove portion, wherein a plurality of the first groove portions are provided based on the second interval and have a predetermined depth. The second groove portion is provided.

  The thermocompression bonding apparatus according to the present invention includes a first substrate having first electrode portions arranged at a predetermined interval in the width direction, and second electrodes arranged at the predetermined interval in the width direction. Thermocompression bonding in which a second electrode portion of the second substrate is arranged and connected to a second substrate having a portion so as to face the first electrode portion of the first substrate via a connection member An apparatus, a pedestal for arranging a substrate to be connected, and a thermocompression bonding jig having a pressure bonding surface for pressure welding and heating from above the second electrode portion of the second substrate, A plurality of the crimping surfaces are provided based on a first interval, and are a first groove part having a predetermined depth, and a second groove part provided perpendicular to the first groove part. A thermocompression bonding jig provided with a plurality of second grooves having a predetermined depth, and pressure welding and heating of the crimping jig. It is characterized by comprising a controller for controlling.

  Further, the substrate connection method according to the present invention includes a first substrate having first electrode portions arranged at a predetermined interval in the width direction, and second electrodes arranged at the predetermined interval in the width direction. A second substrate having a portion is provided, a connection member is disposed on the first electrode portion, and the second electrode is disposed so as to face the first electrode of the first substrate through the connection member. A second electrode portion of the substrate is disposed, and has a pressure-bonding surface that can cover the second electrode portion from above the second electrode portion of the second substrate, and the pressure-bonding surface has a first interval. A plurality of first groove portions having a predetermined depth and a second groove portion provided perpendicularly to the first groove portions, the plurality of grooves being provided based on the second interval, A thermocompression bonding jig having a second groove portion having a predetermined depth is pressed and heated to connect the first substrate and the second substrate. It is characterized in Rukoto.

  Highly reliable board-to-board connection is possible.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. FIG. 1 is a view showing a thermocompression bonding apparatus according to an embodiment of the present invention. As shown in FIG. 1, the thermocompression bonding apparatus 1 according to the present invention includes a pedestal 10, a crimping jig 20, and a controller 30 as main components.

  The pedestal 10 serves as a table on which, for example, two substrates to be connected (a first substrate 100 and a second substrate 200 described later) are placed.

  The crimping jig 20 is a jig for connecting the two substrates. As will be described later, the crimping jig 20 is placed so as to cover the second connection portion 204 (see FIG. 4) on the second substrate 200, and the first and second crimping jigs 202 are pressurized and heated to thereby form the first The substrate 100 and the second substrate 200 are connected via the connection member 300. The crimping jig 20 is connected to the controller 30 in order to be controlled by the controller 30.

  The crimping jig 20 is made of a material such as ceramic or metal, and has a plurality of groove portions (a first groove portion 20b and a second groove portion 20c described later). The shape of the crimping jig 20 will be described later.

  The controller 30 is a control unit that adjusts the pressurization and heating of the crimping jig 20. The controller 30 includes a display unit 31 that displays a pressurization and heating profile and the like, and an operation unit 32 for operating the position, pressurization, and heating of the crimping jig 20.

  Next, a substrate connecting method according to an embodiment of the present invention will be described. FIG. 2 is a flowchart showing a substrate connection method according to an embodiment of the present invention. FIG. 5 is a diagram showing each step when the substrate connecting method according to the embodiment of the present invention is performed.

  First, substrates (first substrate 100 and second substrate 200) to be connected are prepared in order to perform substrate connection according to the present embodiment (step S10).

  FIG. 3 is a view showing the first substrate 100. FIG. 3A is a view of the first substrate 100 as viewed from the top, and FIG. 3B is a view showing a cross section taken along the line AA. As shown in FIG. 3, in the first substrate 100, a plurality of wirings 102, which are conductive materials, are laminated at a predetermined interval on a base material 101, which is an insulating material, and a covering material 103 is laminated thereon. . In addition, the first substrate 100 is provided with a region of the first connection portion 104 where a part of the wiring 102 is exposed in order to perform inter-substrate connection. Note that the covering material 103 is directly laminated on the base material 101 in a portion where the wiring 102 is not provided. The exposed portion of the wiring 102 serves as an electrode.

  FIG. 4 is a view showing the second substrate 200. FIG. 4A is a view of the second substrate 200 viewed from the top surface, and FIG. 4B is a view showing a BB cross section. As shown in FIG. 4, in the second substrate 200, a plurality of wirings 202 that are conductive materials are stacked on a base material 201 that is an insulating material at the same predetermined intervals as the wirings 102, and a covering material 203 is formed thereon. Are stacked. In addition, the second substrate 200 is provided with a region of a second connection portion 204 where a part of the wiring 202 is exposed in order to perform inter-substrate connection. Note that the covering material 203 is directly laminated on the base material 201 in a portion where the wiring 202 is not provided. The exposed portion of the wiring 202 serves as an electrode. The second substrate 200 is, for example, an FPC.

  After preparing the substrate shown in step S10, next, the first substrate 100 is placed on the base 10 as shown in FIG. 5A (step S20).

  Next, as shown in FIG. 5B, the connection member 300 is disposed on the first connection portion 104 of the first substrate 100 (step S30). Here, the connection member 300 is, for example, ACF, ACP, NCP (Non-Conductive Paste), NCF (Non-Conductive Film), or other thermoplastic adhesives.

  Next, as shown in FIG. 5C, the second substrate 200 is placed on the first substrate 100 (step S40). In this arrangement, the first connection unit 104 and the second connection unit 204 are arranged to face each other. FIG. 5F shows the details of the crimping jig 20.

  Next, as shown in FIG. 5D, by operating the controller 30, the pressure bonding jig 20 is brought into contact with and pressed from the second substrate 200 (step S50). Further, the crimping jig 20 is heated by operating the controller 30 (step S60). The pressurization and heating are maintained for a predetermined time, and the first substrate 100 and the second substrate 200 are connected to each other. It should be noted that step S50 and step S60 may be interchanged to heat the crimping jig 20 in advance.

  FIG. 6 is a view showing a CC cross section of FIG. Here, FIG. 6A shows the whole, and FIG. 6B shows the details of the crimping jig 20. As can be seen from FIG. 6, the crimping jig 20 has a width W that is substantially the same as that of the second substrate 200, and a part of the crimping surface 20 a that serves as an electrode is a wiring 102. And a plurality of groove portions (first groove portions 20b) facing the wiring 202.

  The depth 20bL of the first groove 20b is preferably at least equal to or greater than the sum of the thickness of the second substrate 200 and the connection member 300, taking into account the biting of the second substrate and the like during crimping.

  As described above, by providing the first groove portion 20b, the surface that is actually in contact with the second substrate 200 in the pressure-bonding surface 20a is reduced, and the pressure per unit area is increased even with the same thrust, and the pressure is increased with less thrust. Can be added. Therefore, it is less necessary to secure a pressure larger than necessary as the specification of the thermocompression bonding apparatus. Therefore, connection reliability can be ensured even if a conventional thermocompression bonding apparatus is used.

  The first interval 20bT is preferably equal to the interval between the wirings (wirings 102 and 202) that are electrodes so that the crimping surface that is actually in contact with the second substrate 200 is provided on the electrodes. Thereby, pressure can be applied intensively on the electrodes, and the connection reliability between the first substrate 100 and the second substrate 200 can be improved.

  7 is a diagram showing the D1-D1 cross section or D2-D2 cross section of FIG. 6, FIG. 8 is a diagram showing the E1-E1 cross section or E2-E2 cross section of FIG. 6, and FIG. 9 is F1 of FIG. It is the figure which showed -F1 cross section or F2-F2 cross section.

  As can be seen from FIGS. 7 to 9, the crimping surface (20a) of the crimping jig 20 has a plurality of grooves (second grooves 20c) provided perpendicular to the first grooves 20b. Yes. Further, it is preferable that both ends of the second groove portion 20c (second interval 20cT) are denser at the both end portions than at the central portion. That is, as shown in FIGS. 7 to 9, the number of second grooves 20c is larger in FIG. 8 than in FIG. 9, and the second groove 20c in FIG. The number of the groove portions 20c is increased.

  The reason why the second interval is provided closer to both end portions than the central portion is because the surface temperature of the crimping jig, the applied pressure, and the amount of adhesive spread are taken into consideration. Details will be described below.

  Since the second interval 20cT is provided closer to both ends than the center portion, the crimping surface 20a of the crimping jig 20 is actually in contact with the second substrate 200 toward the end in the length L direction. A surface becomes small and a big pressure will be added per unit area compared with a center part.

  Further, since the second interval 20cT is provided closer to both ends than the center portion, the surface area of the first groove portion 20b and the second groove portion 20c that is in contact with the outside air formed in the depth 20cL direction is long. The closer to the end in the L direction, the wider, and heat conduction is easier to promote than at the center. That is, since heat conduction is promoted at the end portion in the length direction, heat at the center portion is easily transmitted to the end portion in the length L direction. Therefore, the problem of the temperature difference between the center portion and both end portions of the thermocompression bonding jig, which has occurred when the thermocompression bonding jig is reduced in size, is easily solved. In addition, it is preferable that the depth 20cL and the depth 20bL are the same depth.

  Experience has shown that with general ACFs and thermoplastic adhesives, the amount of resin expansion during thermocompression bonding tends to expand in response to increases in applied pressure and temperature. This is because, for example, in the case of a conventional flat-type crimping jig that does not have the grooves 20b and 20c described above, pressure is applied at the end compared to the center, and the fluidity of the adhesive resin decreases. Etc.

  As described above, the formation of the groove 20c has an effect of promoting the flow of the connection member 300. As a result, the connection member 300 is spread evenly in the length direction of the crimping jig, and as a result, the connection reliability between the first substrate 100 and the second substrate 200 can be improved.

  Next, as shown in FIG. 5E, the crimping jig 20 that has been in contact is released (step S70), and the inter-substrate connection between the first substrate 100 and the second substrate 200 is completed.

  By performing the above-described substrate connection method, highly reliable substrate-to-substrate connection is possible.

The figure which showed the thermocompression bonding apparatus which concerns on embodiment of this invention. The flowchart which showed the board | substrate connection method which concerns on embodiment of this invention. The figure which showed the 1st board | substrate 100. FIG. The figure which showed the 2nd board | substrate 200. FIG. The figure which showed each step at the time of implementing the board | substrate connection method which concerns on embodiment of this invention. The figure which showed CC cross section of FIG.5 (d). The figure which showed the D1-D1 cross section or D2-D2 cross section of FIG. The figure which showed the E1-E1 cross section or E2-E2 cross section of FIG. The figure which showed the F1-F1 cross section or F2-F2 cross section of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1a Thermocompression bonding apparatus 10 Base 20,21 Crimping jig 20a Crimp surface 20b 1st groove part 20c 2nd groove part 20bT 1st space | interval 20cT 2nd space | interval 20bL, 20cL Depth 30, 30a Controller 31 Display part 32 Operation unit 300 Connection member 100 First substrate 101 Base material 102 Wiring 103 Coating material 104 First connection unit 200 Second substrate 201 Base material 202 Wiring 203 Coating material 204 Second connection unit

Claims (9)

Connecting a first substrate having first electrode portions arranged at a predetermined interval in the width direction and a second substrate having second electrode portions arranged at a predetermined interval in the width direction A thermocompression bonding jig having a crimping surface for
The crimping surface is
A plurality of first grooves having a predetermined depth provided based on the first interval;
A second groove part provided perpendicular to the first groove part, wherein a plurality of second groove parts are provided based on the second interval and have a predetermined depth. Thermocompression jig.   The thermocompression bonding jig according to claim 1, wherein the first interval is the predetermined interval.   The thermocompression bonding jig according to claim 1, wherein the second interval is denser at both end portions than at the center portion. Connecting a first substrate having first electrode portions arranged at predetermined intervals in the width direction and a second substrate having second electrode portions arranged at predetermined intervals in the width direction A thermocompression bonding apparatus for arranging and connecting the second electrode portion of the second substrate so as to face the first electrode portion of the first substrate via a member,
A pedestal for placing the board to be connected;
A thermocompression-bonding jig having a pressure-bonding surface for pressure-welding and heating from above the second electrode portion of the second substrate, wherein a plurality of the pressure-bonding surfaces are provided on the basis of a first interval; A first groove portion having a depth of 2 and a second groove portion provided perpendicularly to the first groove portion, wherein a plurality of grooves are provided based on the second interval and have a predetermined depth. A thermocompression bonding jig provided with two grooves,
A thermocompression bonding apparatus comprising a controller for controlling the pressure welding and heating of the crimping jig.   The thermocompression bonding apparatus according to claim 4, wherein the first interval is the predetermined interval.   The thermocompression bonding apparatus according to claim 4, wherein the second interval is denser at both end portions than at the center portion. A first substrate having first electrode portions arranged at predetermined intervals in the width direction and a second substrate having second electrode portions arranged at predetermined intervals in the width direction are prepared. ,
A connecting member is disposed on the first electrode portion;
Disposing the second electrode portion of the second substrate so as to face the first electrode of the first substrate via the connection member;
There is a pressure-bonding surface that can be covered by the second electrode portion from above the second electrode portion of the second substrate, and a plurality of the pressure-bonding surfaces are provided on the basis of the first interval, and have a predetermined depth. A first groove portion having a first groove portion and a second groove portion provided perpendicular to the first groove portion, wherein a plurality of second groove portions are provided based on a second interval and have a predetermined depth. Press the thermocompression bonding jig
A substrate connecting method, wherein the crimping jig is heated to connect the first substrate and the second substrate.   The substrate connection method according to claim 7, wherein the first interval is the predetermined interval.   The substrate connection method according to claim 7, wherein the second interval is denser at both end portions than at the center portion.

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