JP2008098257A - Connection structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connection structure capable of being reduced in thickness and size while maintaining connection reliability of a flexible wiring board etc. <P>SOLUTION: The connection structure has a rigid printed wiring board 12 in which a wiring 11 having protrusions 13 is formed, a flexible printed wiring board 22 in which a wiring 21 having protrusions 23 is formed, and an anisotropic conductive sheet 30 having through electrodes 36. The protrusions 13, 23 are fitted to the common through electrodes 36, and this configuration allows the printed wiring boards 12, 22 to be firmly connected. Either the protrusions 13, 23 or the through hole 36 is tapered to enable a smooth fitting operation. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a connection structure for connecting wirings used in various electric devices such as a mobile phone, in particular, a flexible wiring board to another printed wiring board.

  2. Description of the Related Art Conventionally, film-shaped wiring bodies, so-called flexible wiring boards, are often arranged particularly in small and light electrical devices such as mobile phones. In recent years, flexible wiring boards have been used more frequently because they are very convenient for electrical connection in devices having an opening / closing mechanism and a rotating mechanism such as a mobile phone. The flexible wiring board is rich in flexibility, but unlike a rigid wiring board having a rigid structure, it is difficult to increase the insertion force when the flexible wiring board is inserted into the insertion port of the connector. Therefore, a non-insertion force connector (ZIF: Zero Interpose Force) is widely used as a connection structure (connector) for connecting a flexible wiring board to another wiring board (see Patent Documents 1 and 2).

  FIGS. 7A and 7B are a plan view and a side view showing the structure of a general ZIF connector. As shown in the figure, in a rigid printed wiring board, a ZIF connector 110 is disposed on a rigid substrate 100 having a rigid structure on which wirings 101 are formed. In the flexible printed wiring board, wiring 201 is formed on a flexible substrate 200. The ZIF connector 110 is provided with a plurality of metal wire-like contacts 103 each connected to the wiring 101. The contact 103 is provided in a U shape when viewed from the side, and an upper end portion of the contact 103 has a hook shape. When connecting, the flexible printed wiring board is inserted into the U-shaped opening of the contact 103 of the ZIF connector 110 with almost no insertion force. Then, in a state where the contact 103 and the wiring 201 are in contact with each other, the lock portion 105 is rotated around the shaft 106 to press the hook-shaped upper end portion of the contact 103 into the flexible substrate 200. This completes the connection between the wirings. The lock portion 105 is locked by both arm portions extending to the side of the ZIF connector 110 when the tip end portion moves to the lowest position.

  By the operation of the ZIF connector 110, the wiring 201 on the flexible substrate 200 and the wiring 101 on the rigid substrate 100 which is a mother board are electrically connected. Then, the flexible printed wiring board is held so that the connection state between the contact 103 and the wiring 201 on the flexible substrate 200 is maintained. Patent Documents 1 and 2 disclose various structures of the lock portion 105 and the contact 103.

Japanese Patent Publication No. 6-65090 Japanese Patent Publication No. 7-24230

  However, as the recent trend toward miniaturization of various electric devices such as mobile phones, when the ZIF connector is required to be thinner and smaller, the reliability of electrical connection in the ZIF connector 110 is maintained. It has become difficult to do.

  That is, there is a limit to reducing the wire-like contactor 103 and the thickness and width dimension of the portion supporting the contactor 103 while maintaining the mechanical strength for keeping the shape in the set state.

  Further, if the thickness and width dimension of the ZIF connector 110 and the contact 103 are reduced, it is difficult to maintain the gripping force of the flexible printed wiring board by the contact 103 of the ZIF connector 110 sufficiently high. On the other hand, if this gripping force is maintained sufficiently high to ensure connection reliability, it is difficult to make the ZIF connector 100 thinner and smaller. For example, when the width of the wirings 101 and 201 is about 0.1 mm and the gap between the wirings is about 0.1 mm due to the narrow pitch, the width of the contact 103 needs to correspond to that, but in that case, The gripping force is weakened and the flexible printed wiring board is very likely to come off.

  The above-described problems occur not only in the connection between the flexible printed wiring board and the rigid printed wiring board but also in the connection between the flexible printed wiring boards, and may also occur in various flexible wiring boards.

  An object of the present invention is to reduce the thickness and size of a connection structure for maintaining an electrical connection between a flexible wiring board and another wiring board, and to maintain connection reliability. To provide a structure.

  In the connection structure of the present invention, a plate-like intermediate member having a cylindrical through electrode is sandwiched between two wiring bodies provided with a protruding portion on the wiring, and the corresponding protruding portion of the wiring is shared through The electrode is fitted to both ends of the electrode.

  As a result, the two wiring bodies are connected to each other by the gripping force generated by the fitting between the through electrode and the protrusion, so that the conventional ZIF connector becomes unnecessary. Therefore, the thickness and width dimension of the entire connection structure can be reduced, and therefore it is possible to cope with the progress of thinning and miniaturization.

  Since either one of the protrusions or the fitting part of the through electrode has a taper, it becomes easy to fit the protrusions of the two wiring bodies to the through electrode.

  When the intermediate member is an elastic body, the gripping force of the protrusion by the intermediate member in the fitting portion is increased, and connection reliability can be ensured.

  The intermediate member retains the elasticity of the intermediate member by adopting a structure in which a porous resin having a plurality of micropores is used as a base material and a through electrode is formed on an inner wall portion including the inside of each micropore of the base material. On the other hand, the occurrence of poor conduction in the through electrode can be suppressed, and the connection reliability can be further improved.

  The connection structure of the present invention is particularly effective when at least one of the first wiring body and the second wiring body is a flexible wiring board.

  According to the connection structure of the present invention, since a plate-like intermediate member having a through electrode is used instead of the conventional ZIF connector, it is possible to cope with the progress of thinning and miniaturization.

(Embodiment 1)
-Overall structure of the connection structure-
FIG. 1 is a plan view of a rigid printed wiring board 12 which is a first wiring body according to the first embodiment. The rigid printed wiring board 12 is generally a wiring board 11 formed on a rigid substrate 10 made of glass epoxy resin or the like. The rigid substrate 10 is not limited to a glass epoxy plate but may be a paper phenol plate, a paper epoxy plate, a fluororesin plate, an alumina plate, or the like. As a material for the wiring 11, a copper alloy is generally used, but is not limited thereto. In the present embodiment, a partial conical protrusion 13 is further formed on the wiring 10. In the present embodiment, a taper is provided on the outer periphery of the protrusion 13, but the taper may not necessarily be provided. That is, even if it is a straight columnar projection, the basic effect of the present invention can be exhibited as long as it can be fitted with a through electrode described later.

  FIG. 2 is a plan view of the flexible printed wiring board 22 which is the second wiring body according to the first embodiment. The flexible printed wiring board 22 is generally a wiring board 21 formed on a flexible substrate 20 made of polyimide resin or the like. As the flexible substrate 20, not only a polyimide plate but also a polyester plate (low temperature use), a glass epoxy plate (thin plate), or the like is used. The material of the wiring 21 is generally a copper alloy, but is not limited to this. In the present embodiment, a partial conical projection 23 is further formed on the wiring 20. In the present embodiment, a taper is provided on the outer periphery of the protrusion 23, but the taper may not necessarily be provided. That is, even if it is a straight columnar projection, the basic effect of the present invention can be exhibited as long as it can be fitted to a through electrode described later.

  3A and 3B are cross-sectional views showing the structure before and after connection of the connection structure according to the embodiment of the present invention. As shown in FIG. 3A, the connection structure includes an anisotropic conductive sheet 30 that is an intermediate member having a rigid printed wiring board 12, a flexible printed wiring board 22, and a through electrode 36 (described in detail later). And. In the state shown in FIG. 3A, the anisotropic conductive sheet 30 is placed on the rigid substrate 10 and then pressed, so that the protruding portion 13 on the wiring 11 becomes the cylindrical through electrode 36 of the through electrode 36. It is mated.

  Then, as shown in FIG. 3 (b), by pressing the flexible printed wiring board 22 in a state where the flexible printed wiring board 22 is installed at a predetermined position on the anisotropic conductive sheet 30, a protrusion on the wiring 21 is obtained. The part 23 is fitted into the cylindrical through electrode 36 of the anisotropic conductive sheet 30.

  In the above-described operation, means for pressing the anisotropic conductive sheet 30 and the flexible printed wiring board 22 are known and commonly used means such as a mechanism using a tightening force by a screw, a cylinder mechanism using hydraulic pressure or pneumatic pressure, and the like. Can be used. Further, when it is desired to release the fitted state for repair or the like, the flexible printed wiring board 22 or the like can be easily removed by heating the connecting portion. Then, after the connection between the rigid printed wiring board 12 and the flexible printed wiring board 22 is completed, the pressing means becomes unnecessary, and thus a conventional ZIF connector having a lock mechanism is unnecessary. However, simple pressing means for always pressing the two wiring bodies and the intermediate member may be provided.

  Here, the number of protrusions 13 (or 23) in each wiring 11 (or 21) is a plurality (eight) in the present embodiment, but the number is not necessarily required, and one for one wiring. Only one protrusion may be used. In the present embodiment, the inner diameter of the through electrode 36 is about 30 to 200 μm. However, as the anisotropic conductive sheet 30, the inner diameter of the through electrode 36 may be 10 μm or less. The thickness of the through electrode 36, that is, the thickness of the anisotropic conductive sheet 30 is about 0.1 to 0.5 mm. In the case of using a through electrode 36 having a large wiring width and an inner diameter of about 200 μm, both projections are fitted to both end portions of one through electrode 36 by fitting one projection portion with respect to one wiring. The gripping force for the wiring boards 13 and 23 can be kept high.

-Structure of anisotropic conductive sheet-
6 (a) to 6 (e) are cross-sectional views showing a manufacturing process of the anisotropic conductive sheet. Hereinafter, the manufacturing process of the anisotropic conductive sheet will be described with reference to FIGS. In the step shown in FIG. 6A, a frame plate 30a that is a porous PTFE membrane is prepared. Generally, methods for producing a porous film using a synthetic resin include a pore making method, a phase separation method, a solvent extraction method, a stretching method, a laser irradiation method, and the like. By forming a porous film using a synthetic resin, elasticity can be given in the plate thickness direction and the dielectric constant can be further lowered. In particular, the porous film obtained by the stretching method (porous PTFE film in the present embodiment) is excellent in heat resistance, processability, mechanical characteristics, dielectric characteristics, etc., and has a uniform pore size distribution. Therefore, it is an optimum material for the base material of the anisotropic conductive sheet.

  The porous PTFE membrane of the present embodiment can be produced by, for example, the method described in Japanese Patent Publication No. 42-13560. First, a liquid lubricant is mixed with the unsintered powder of PTFE, and extruded into a tube shape or a plate shape by ram extrusion. When a thin sheet is desired, the plate is rolled with a rolling roll. After the extrusion rolling process, the liquid lubricant is removed from the extruded product or the rolled product as necessary. When the extruded product or the rolled product thus obtained is stretched at least in a uniaxial direction, unsintered porous PTFE is obtained in the form of a film. An unsintered porous PTFE membrane is highly porous when heated and stretched to a temperature of 327 ° C. or higher, which is the melting point of PTFE, while being fixed so that shrinkage does not occur. A PTFE membrane is obtained. When the porous PTFE membrane is in a tube shape, a flat membrane can be obtained by opening the tube.

  Next, in the step shown in FIG. 6 (b), the mask films 31 and 32 are fused to both surfaces of the frame plate 30a, which is a porous PTFE film obtained by the stretching method, to form a laminate 33 having a three-layer structure. The through-hole 35 is formed in the whole laminated body 33 (refer to a broken line). As the mask films 31 and 32, a PTFE film made of the same material as that of the frame plate 30a, preferably a porous PTFE film is used. At this time, for example, three layers of porous PTFE membranes are fused to each other by sandwiching both surfaces of three laminated porous PTFE membranes with two stainless steel plates and heating each stainless steel plate to a high temperature. Can do.

  In general, examples of a method for forming a through hole in a film thickness direction at a specific position of a synthetic resin include a chemical etching method, a thermal decomposition method, an ablation method using laser light or soft X-ray irradiation, and an ultrasonic method. For the laminate 33 made of a porous PTFE film formed by a stretching method, a method of irradiating synchrotron radiation or laser light having a wavelength of 250 nm or less, and an ultrasonic method are preferable. The diameter of the through-hole 35 by the laser method is generally about 5 to 100 μm. In the present embodiment, the diameter of the through hole 35 is 30 to 200 μm.

  Although description about the method of forming the through-hole 35 by the ultrasonic method is omitted, it is as disclosed in Japanese Patent Application Laid-Open No. 2004-265844 (see paragraphs [0042] to [0051]). The cross-sectional shape of the through hole 35 is arbitrary, such as a circle, a star, an octagon, a hexagon, a quadrangle, and a triangle. Further, the through hole 35 may be formed by machining using a drill or the like.

  Next, in the step shown in FIG. 6 (c), the catalyst is applied through conditioning, washing and pre-dip of the laminate 33. The purpose of conditioning is to make the surface of PTFE having water repellency as hydrophilic as possible, and to facilitate the adhesion of the catalyst (Pd) in a later step. For the porous PTFE membrane, a solution containing alcohol such as ethanol or a surfactant is used as a conditioner, and the conditioner is infiltrated to each fiber in the porous structure.

  And after completion | finish of a pre-dip process, the laminated body 33 is immersed in the catalyst liquid (for example, a tin chloride-palladium chloride colloid liquid) containing Pd, and the surface of each fiber of PTFE constituting the laminated body 33 is made of a Pd compound. Colloidal particles are adhered to form a colloidal particle adhesion region 34 formed by the colloidal particles adhering to the surface of each fiber on the surface region such as the inner wall of the through hole 35. In the colloidal particle adhesion region 34, the colloidal particles are rarely a continuous layer and are often island-shaped layers. At this time, the colloidal particle adhesion region 34 is also formed in the surface region (hatched region shown in FIG. 3C) where the mask films 31 and 32 are exposed. Even if the pre-dip step is omitted, the effect of the present invention can be exhibited.

  Next, in the step shown in FIG. 6D, the mask films 31 and 32 are peeled off from both surfaces of the frame plate 30a. At this time, the colloidal particle formation region 34 is not formed on both surfaces of the frame plate 30a. On the other hand, the colloidal particle adhesion region 34 is also formed on the side edge of the frame plate 30a. The colloidal particle adhesion region 34 formed in this part is appropriately formed after the end of this step or after the end of the electroless plating. Removed.

  Next, in the step shown in FIG. 6E, electroless plating is performed to form the through electrode 36. Before that, a colloidal particle adhesion region 34 made of a Pd compound is used by using diluted hydrochloric acid, diluted sulfuric acid, or the like. A process for activating Pd therein is performed. Thereby, activated catalyst particles are formed. The catalyst particles generally contain a Pd compound (for example, palladium-tin chloride) and simple Pd, and Pd is exposed on the surface even if all the colloidal particles are not changed to simple Pd. If it does, the function as a catalyst of electroless plating can be exhibited. Thereafter, the treatment liquid adhering to the surface of the frame plate 30a is washed away with water.

  In the electroless plating step, Cu is deposited around the catalyst particles from a copper sulfate solution or the like by electroless Cu plating using a solution containing copper ions such as copper sulfate and a reducing agent such as formaldehyde. Since the deposited Cu also has catalytic activity, a Cu layer having a thickness corresponding to the plating time is formed. When the electroless plating of Cu is completed, the process proceeds to the next step after washing with water.

  Next, in order to adhere the catalyst to the surface of the Cu layer, the frame plate 30a is immersed again in the catalyst solution. Here, a palladium chloride solution is used as the catalyst solution. Pre-dip and conditioning are not performed, and the catalyst liquid does not contain tin chloride, so that the catalyst particles hardly adhere to the exposed portions of PTFE that are not covered with the Cu layer. Thereafter, washing with water is performed to remove the catalyst solution remaining on the surface.

  Next, an Ni alloy layer (actually Ni-P alloy plating) is used on the Cu layer by electroless Ni plating (actually Ni-P alloy plating) using a solution containing Ni ions such as nickel sulfate and a reducing agent containing phosphinate ions. Is deposited with a Ni-P alloy layer). Then, it is washed with water.

  Thereafter, an Au layer is formed by displacement gold plating. When an electrochemically noble metal (Ni) is immersed in a solution containing electrochemically noble metal (Au) ions, noble metal ions are reduced by electrons released by the dissolution of the noble metal, A noble metal (Au) coating is deposited on the base metal (Ni) surface. Through the steps described above, the through electrode 36 composed of catalyst particles, a Cu layer, a Ni—P alloy layer, and an Au layer is formed. Note that the Au layer may be formed by autocatalytic electroless plating after displacement plating. Then, the electroless plating process is completed by drying through water washing and alcohol substitution.

  In the manufacturing process of the anisotropic conductive sheet 30, the frame plate 30 a is sandwiched between the mask films 31 and 32 from both sides to form the laminated body 33, and then the through holes are formed and immersed in the catalyst solution. However, the stacked body 33 is not necessarily formed. For example, the steps shown in FIGS. 3C to 3E, such as formation of through holes, application of a catalyst, activation treatment, and electroless plating, may be performed on the frame plate alone. In that case, an electroless plating layer is also formed on the plate surface of the frame plate, but may be removed by polishing or the like. However, by forming the through hole 35 in the stacked body 33 as in the present embodiment, a highly accurate through hole 35 can be obtained. In addition, the manufacturing cost can be reduced by not forming an extra electroless plating layer.

  The anisotropic conductive sheet 30 formed by the above steps includes a through electrode 36 serving as a conductive portion formed on the inner wall portion of the through hole 35. Thereby, the anisotropic conductive function of having conductivity in the plate thickness direction and no conductivity in the plate surface direction is provided. In order to prevent an electrical short circuit between the through electrodes 36 serving as a conduction portion, the frame plate 30a needs to be an insulator. In the present embodiment, in order to make the anisotropic conductive sheet 30 have both elasticity and high strength, the frame plate 30a is made of a synthetic resin of a porous film.

  Synthetic resin materials constituting the porous membrane frame plate 30a of the present embodiment include polytetrafluoroethylene (PTFE), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), tetrafluoroethylene / perfluoroalkyl. Fluorine resins such as vinyl ether copolymer (PFA), polyvinylidene fluoride (PVDF), polyvinylidene fluoride copolymer, ethylene / tetrafluoroethylene copolymer (ETFE resin); polyimide (PI), polyamideimide (PAI) ), Polyamide (PA), modified polyphenylene ether (mPPE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), polysulfone (PSU), polyethersulfone (PES), liquid crystal polymer (LCP), etc. -Engineering plastic, and the like. Among these, PTFE has excellent characteristics when comprehensively considering heat resistance, workability, mechanical characteristics, dielectric characteristics, and the like. Therefore, in the present embodiment, a porous PTFE film (porous polytetrafluoroethylene film) is used as the frame plate 30a. In the present embodiment, as will be described later, since a porous PTFE membrane obtained by a stretching method is used, the frame plate 30a is formed by very thin fibers (fibrils) formed by PTFE and the fibers, respectively. It has a fine fibrous structure (porous structure) composed of nodes (nodes) connected to each other.

  In the present embodiment, the porous PTFE membrane used as the frame plate 30a preferably has a porosity of about 20 to 80%. The porous PTFE membrane preferably has an average pore diameter of 10 μm or less or a bubble point of 2 kPa or more from the viewpoint of fine pitching of the conducting part, and an average pore diameter of 1 μm or less or a bubble point of 10 kPa or more. It is more preferable. The thickness of the porous PTFE membrane can be appropriately selected according to the purpose of use and the location of use, but is usually 0.05 to 3 mm.

  The through electrode 36 has a multilayer metal plating layer (electroless plating layer) with a tube thickness of 0.2 to 5 μm on the inner wall portion including the inner wall surface of the through hole 35 and the inside of the fine hole. That is, in the electroless plating, the through electrode 36 is formed in the surface region including the fibers of the porous PTFE film by the catalyst particles and the metal that have entered the fine holes from the inner wall surface. In the present embodiment, the through electrode 36 is constituted by a Cu layer, a Ni alloy layer (Ni—P alloy layer), and an Au layer deposited using catalyst particles attached to the fiber surface as nuclei. However, the Cu layer is not necessarily required.

  As described above, during electroless plating, the catalyst particles penetrate not only through the inner wall surface of the through-hole 35 but also through the micropores of the porous PTFE film and adhere to the fiber surface. The porous PTFE membrane is deposited by penetrating into the inside from the micropores. That is, the through electrode 36 includes not only the multilayer metal plating layer but also the fibers of the porous PTFE film. Since the through electrode 36 is formed by adhering to the surface of the resin portion having a porous structure, the through electrode 36 itself has a characteristic of being porous. Then, by applying a compressive load in the thickness direction of the anisotropic conductive sheet 30, conductivity is imparted only in the thickness direction of the anisotropic conductive sheet 30 while maintaining insulation between the through electrodes 36. (Anisotropic conductivity). Further, when the compressive load is removed, the entire anisotropic conductive sheet 30 including the through electrode 36 is elastically recovered, so that the anisotropic conductive sheet 30 of the present embodiment can be used repeatedly.

  It is preferable that the tube thickness of the through electrode 36 is such that the resistance value of the through electrode 36 which is a conducting portion in the fitted state is 0.1Ω or less.

  According to the present embodiment, instead of the conventionally used ZIF connector, the wires 11 of the rigid printed wiring board 12 and the flexible printed wiring board 22 are arranged via the plate-like anisotropic conductive sheet 30 (intermediate member). Since the electrical connection between 21 is performed, it is possible to easily cope with a reduction in thickness and size. That is, since the plate-like anisotropic conductive sheet 30 is used instead of the ZIF connector, the thickness can be significantly reduced. Even if the thickness of the anisotropic conductive sheet 30 is reduced to about 0.1 mm, a sufficiently high strength can be obtained. If necessary, a large gripping force for the printed wiring boards 12 and 22 can be secured via the many protrusions 13 and 23 and the through electrodes 36.

  In particular, in the present embodiment, like the anisotropic conductive sheet 30, the porous PTFE that is an elastic body is used as the base material of the anisotropic conductive sheet 30. The gripping force with respect to the printed wiring boards 12 and 22 is improved by utilizing the elastic deformation at the time of fitting between the protrusion 36 and the protrusions 13 and 23. Therefore, the reliability of electrical connection by the connection structure is further improved.

  Among porous resins, especially porous PTFE has high strength and heat resistance, and since there is almost no deterioration in elasticity due to repeated loading, it can prevent a decrease in gripping force due to deterioration in elasticity even after long-term use. Can do.

(Embodiment 2)
FIG. 4 is a cross-sectional view showing a connection structure according to the second embodiment. The members common to FIGS. 3A and 3B in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. As shown in the figure, in the present embodiment, the protrusions 13 a and 13 b on the wirings 11 and 21 have a cylindrical shape without a taper, and the both ends of the through electrode 36 are tapered. Also in this case, it can be easily understood that the same effects as those of the first embodiment can be obtained. The tapered shape of the through electrode 36 can be realized by performing the formation of the through hole 35 described in the first embodiment (see FIG. 6C) with a drill and using the taper at the tip of the drill. The conical through hole 35 can also be formed by laser processing.

(Other embodiments)
FIG. 5 is a cross-sectional view of rigid printed wiring board 12 or flexible printed wiring board 22 according to a modification of the first embodiment. The members common to FIGS. 3A and 3B in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. In this modification, bump-like protrusions 13b and 23b are provided on the wirings 11 and 21, respectively. By having such a structure, workability for fitting is good and the protrusions 13b and 23b are difficult to come off, so that particularly excellent gripping force can be exhibited. The protrusions 13b and 23b can be formed using a well-known and commonly used bump formation process.

  In the above-described embodiment, the anisotropic conductive sheet 30 in which the catalyst particles and the electroless plating layer are formed on the inner wall portion of the through hole 35 of the frame plate 30a made of the porous PTFE film is used as the intermediate member. However, the intermediate member of the present invention is not limited to such an anisotropic conductive sheet 30. For example, a through-hole may be formed in a plate made of a general-purpose resin that is not porous, and a through-electrode may be provided by electroless plating or the like.

  On the other hand, since the resin constituting the intermediate member has elasticity, the gripping force for gripping the flexible printed wiring board 22 can be increased, but the elasticity of the through electrode 36 made of metal is small. Therefore, since the resin constituting the intermediate member is porous, the through electrode 36 is also porous, and the entire through electrode 36 has elasticity like a spring. Therefore, it is preferable to use a porous resin as the base resin of the intermediate member.

  Among the porous resins, as described above, porous PTFE has high reliability in long-term use, but is expensive, but uses other inexpensive porous resins for the purpose of reducing costs. Is also possible.

  In the above embodiment, an example in which the rigid printed wiring board 12 (abbreviated as PCB) is used as the first wiring body and the flexible printed wiring board 22 (abbreviated as FPC) is used as the second wiring body has been described. The first wiring body is not limited to the rigid printed wiring board 12 but may be a flexible printed wiring board. Moreover, even if it is a flexible wiring board, there exists what is called a flexible flat cable (FFC), and it can be used for the connection of these various wiring boards. However, it is desirable that one is a flexible wiring board. This is because a simpler structure than that of the present invention can be adopted when electrical connection is made between rigid wiring boards.

  The structure of the embodiment of the present invention disclosed above is merely an example, and the scope of the present invention is not limited to the scope of these descriptions. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

  INDUSTRIAL APPLICABILITY The present invention can be used as a connector that performs electrical connection between wirings between a flexible wiring board mounted on an electric device such as a mobile phone and another wiring board.

3 is a plan view of a rigid printed wiring board that is a first wiring body according to Embodiment 1. FIG. 3 is a plan view of a flexible printed wiring board that is the second wiring body according to Embodiment 1. FIG. (A), (b) It is sectional drawing which shows the connection structure which concerns on Embodiment 2 of this invention. 6 is a cross-sectional view of a rigid printed wiring board and a flexible printed wiring board according to a modification of the first embodiment. FIG. (A)-(e) is sectional drawing which shows the manufacturing process of the anisotropically conductive sheet which concerns on embodiment. (A), (b) is the top view and side view which show the structure of the connector of a general ZIF structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rigid board | substrate 11 Wiring 12 Rigid printed wiring board 13 Protruding part 20 Flexible board 21 Wiring 22 Flexible printed wiring board 23 Protruding part 30 Anisotropic conductive sheet 30a Frame board 31 Mask film 32 Mask film 35 Through-hole 36 Through-electrode

Claims (5)

A first wiring body on which a first wiring having a protrusion is formed;
A second wiring body on which a second wiring having a protrusion is formed;
A plate-like intermediate member having a cylindrical through electrode,
The connection structure in which the protrusion of the first wiring and the protrusion of the second wiring are respectively fitted to both ends of a common cylindrical through electrode. The connection structure according to claim 1,
The connection structure in which either one of the protrusion or the through electrode has a tapered portion. The connection structure according to claim 1 or 2,
The connection structure, wherein the intermediate member is an elastic body. In the connection structure in any one of Claims 1-3,
The intermediate member is
Based on a porous resin having a plurality of micropores,
The through electrode is a connection structure formed on an inner wall portion including the inside of each micropore of the base material. In the connection structure in any one of Claims 1-4,
A connection structure in which at least one of the first wiring body and the second wiring body is a flexible wiring board.

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