JP2014082381A - Connection method, manufacturing method for connector and connection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow for double-sided mounting while suppressing deformation of a shield can, in a process for connecting a component to the other surface of a substrate, provided with a shield can, by using an ACF.SOLUTION: A connection device includes a pedestal 21, an elastic member 22 provided on the pedestal 21, and supporting one surface 1a of a substrate 1 previously connected with a frame member 3, and a press head 23 for pressing an electronic component 6 mounted on the other surface 1b of the substrate 1 via an adhesive 7. The sidewall 3a of the frame member 3 is aligned with the vicinity of the center of a support surface 22a of the elastic member 22 for supporting one surface 1a of the substrate 1, and then the electronic component 6 mounted at a part of the other surface 1b, corresponding to a part provided with the sidewall 3a, is pressed by means of the press head 23.

Description

  The present invention relates to a connection method for connecting a component using an anisotropic conductive film on the other surface of a substrate in which an electronic component and a shield can for covering the electronic component are previously provided on one surface, a method for manufacturing a connection body, and a connection device About.

  As a method of mounting electronic components such as ICs and flexible substrates on a rigid printed circuit board, an anisotropic conductive film (ACF) is placed between the substrate and the electronic component, and heat pressing is performed by soldering. This is advantageous in that it can be mounted at a low temperature in a short time compared to the connection. In recent years, mainly in mobile devices such as mobile phones, notebook PCs, and portable game machines, the trend toward smaller, lighter and thinner features and higher functionality has increased. On the other hand, high-density mounting has been demanded. Therefore, double-sided mounting in which components are mounted on both sides of the board is effective as means for realizing high-density mounting in these portable devices.

  In the mounting method using the anisotropic conductive film, as a method of performing double-sided mounting, the one surface of the substrate on which one part is mounted in advance is supported by an elastic member such as rubber and the other surface of the substrate is anisotropic conductive film. After mounting the electronic component, the heating is performed with a heater tool from above the electronic component. As a result, it is possible to eliminate variations in the pressing force caused by a buffer against a component that is previously mounted on one surface of the board and a difference in uneven height between components mounted on the one surface.

  By the way, a part of components mounted on a substrate may be covered with a shield can as a measure against so-called EMC (Electro Magnet Compatibility). This shield can is generally composed of a frame and a lid, and is mounted by soldering the frame to a substrate, inspecting the mounting state and operation of components, and finally fitting the lid. However, since the shield can is formed of a thin metal plate such as an aluminum alloy, when a double-sided mounting is performed using an anisotropic conductive film on the back side of the board after connecting the frame to one side of the board, There is a possibility that the frame body is deformed by pressurization and the lid body cannot be fitted thereafter. In addition, even when the lid can be fitted due to the deformation of the frame, a gap is generated between the frame and the lid, which may reduce the electromagnetic shielding function.

  Here, there is a method in which the above-mentioned cushioning material is interposed between one surface of the substrate and the cradle. However, when the rubber hardness is high, deformation and peeling of the frame of the shield can cannot be suppressed. If the pressure is lowered, the board tilts when the parts are thermally pressed to the other side of the board, and the parts cannot be pressed evenly. In addition, there is a problem that the shield can frame is locally pressed and deformed or peeled off. is there.

  In addition, since components such as connectors are often mounted near the outer edge of the board, when the outer edge of the board is pressed, the board tilts and this also applies pressure to the frame of the shield can and deforms it. There is a risk of peeling.

  For this reason, at present, the board space cannot be effectively utilized, such as mounting the ACF component while avoiding the back surface of the area covered with the shield can, or mounting the ACF only on the same side as the side where the shield can is provided. Moreover, it has become a limiting factor for the increase in the size of the substrate and the circuit design (see FIGS. 16A and 16B).

JP 2010-129682 A JP 2007-214434 A

  The present invention has been made in view of the above-described problems, and an anisotropic conductive film is used to connect a component to the other surface of a substrate on which an electronic component and a shield can that covers the electronic component are provided in advance. It is an object of the present invention to provide a connection method, a connection body manufacturing method, and a connection device that enable double-sided mounting while suppressing deformation of the shield can.

  In order to solve the above-described problem, a connection method according to the present invention includes a cradle and an elastic member that is provided on the cradle and supports the one surface of the substrate having a frame-like member connected to the one surface in advance. A pressing head that presses an electronic component mounted on the other surface of the substrate via an adhesive, and the side wall of the frame-shaped member is disposed near the center of the supporting surface that supports one surface of the substrate of the elastic member. In addition, the electronic component mounted on the portion on the other surface corresponding to the portion where the side wall is provided is pressed by the pressing head.

  The connection body manufacturing method according to the present invention includes a cradle, an elastic member which is provided on the cradle and supports the one surface of the substrate having a frame-like member connected to the one surface in advance, and other than the substrate. A pressing head that presses an electronic component mounted on the surface via an adhesive, and aligns the side wall of the frame-shaped member near the center of the support surface that supports one surface of the substrate of the elastic member, and the pressing The head is used to press and connect the electronic component mounted at the location on the other surface corresponding to the location where the side wall is provided.

  Further, the connection device according to the present invention is provided on the cradle, the elastic member that is provided on the cradle and supports the one surface of the substrate having a frame-like member connected to the one surface in advance, and is bonded to the other surface of the substrate. A pressing head that presses an electronic component mounted via an agent, and the elastic member is formed on the substrate on which the electronic component is mounted at a location on the other surface corresponding to a location where the side wall is provided. The position corresponding to the mounting part of the electronic component is supported, and the electronic component is pressed by the pressing head.

  According to the present invention, since the side wall of the frame-shaped member is aligned near the center of the elastic member, the elastic member can support the side wall without a gap even when the substrate is pressed by the pressing head. The pressure can be evenly distributed to the frame member. Therefore, the present invention can prevent side wall deformation due to pressure concentration.

It is a perspective view which shows the printed circuit board to which this invention was applied. It is sectional drawing which shows the printed circuit board to which this invention was applied. It is a perspective view which shows a shield can. It is a perspective view which shows the process of connecting the connecting terminal formed in the connecting terminal part of a printed circuit board, and the connecting terminal of a flexible substrate with an anisotropic conductive film. It is sectional drawing which shows an anisotropic conductive film. It is sectional drawing which shows the connection apparatus and connection process to which this invention was applied. It is sectional drawing which shows the connection apparatus and connection process to which this invention was applied. It is sectional drawing which shows the process pressurized according to the position where the side surface of the frame body remove | deviated from the upper surface center of the elastic member. It is sectional drawing which shows the state which the elastic member protruded from the press head slidably contacts to a flexible substrate. It is sectional drawing which shows the state which does not protrude from a press head when an elastic member is compressed. 6 is a cross-sectional view showing a connection process according to Embodiment 1. FIG. 10 is a cross-sectional view showing a connection process according to Embodiment 2. FIG. 10 is a cross-sectional view illustrating a connection process according to Example 3. FIG. 10 is a cross-sectional view showing a connection process according to Comparative Example 1. FIG. It is a figure for demonstrating the misalignment of connection terminals. It is a figure which shows the conventional printed circuit board to which the shield can was connected, (a) is a perspective view, (b) is sectional drawing.

  Hereinafter, a connection method, a connection body manufacturing method, and a connection device 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 following embodiments, and various modifications can be made without departing from the scope of the present invention. Further, the drawings are schematic, and the ratio of each dimension may be different from the actual one. Specific dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

[Printed board]
First, a printed circuit board to which electronic components are connected by a connection device to which the present invention is applied will be described. As shown in FIG. 1, the printed circuit board 1 is a so-called rigid board, on which various wiring patterns are formed, and electronic components such as an IC, a capacitor, and a connector are mounted. Further, the printed circuit board 1 is mounted on both sides in order to achieve high-density mounting, and as shown in FIG. 2, a shield can 2 that covers a semiconductor chip or the like is connected to one surface 1a by solder or the like as an EMC measure. ing.

  The shield can 2 is formed of a lightweight metal such as an aluminum alloy, and includes a frame-like frame body 3 and a lid body 4 that closes the frame body 3. As shown in FIG. 3, the frame 3 is provided with a side wall 3 a surrounding a region where a semiconductor chip or the like on the one surface 1 a of the printed board 1 is mounted, and an upper side is open. The lid 4 is attached to the frame 3 to cover the open end and close the inside of the frame 3.

  The shield can 2 is formed by inspecting the mounting state and operation of the components after the various components such as the semiconductor chip and the frame 3 are connected to a predetermined position by reflow soldering or the like, and finally inserting the lid 4 Mounted on the printed circuit board 1. Here, the printed circuit board 1 is provided with the side wall 3a of the frame body 3 in the vicinity of the outer edge portion of the one surface 1a in order to effectively use the space and realize space saving, and the distance from the side wall 3a to the outer edge portion of the substrate. For example, x is 1 mm.

  Further, the printed circuit board 1 is mounted with an IC, a capacitor, a connector, and the like on the other surface 1b, and as shown in FIG. 4, a connection terminal portion 5 including a plurality of connection terminals 5a is formed in the vicinity of the outer edge portion. A flexible substrate 6 on which a predetermined circuit or conductor pattern is formed as an electronic component is connected to the connection terminal portion 5. The flexible substrate 6 is formed with a plurality of connection terminals 6 a, and after various components and the frame 3 are connected to the one surface 1 a of the printed circuit board 1, the flexible substrate 6 is connected to the connection terminal portion 5 via the anisotropic conductive film 7. .

  Specifically, the anisotropic conductive film 7 is temporarily attached to the connection terminal portion 5, and the flexible substrate 6 is temporarily mounted thereon. At this time, alignment adjustment of the connection terminals between the flexible substrate 6 and the connection terminal portion 5 is performed. And it heat-presses for a predetermined | prescribed pressure and predetermined | prescribed time from the flexible substrate 6 with the press head 23 heated to the hardening temperature of the binder resin 10. FIG.

  In the anisotropic conductive film 7, the binder resin 10 is fluidized and flows out between the connection terminals 5 a and 6 a of the flexible substrate 6 and the connection terminal portion 5, and the conductive particles 11 are transferred to the connection terminals 5 a and 6 a. It is pinched and cured in this state. Thereby, a connection body in which the printed board 1 and the flexible board 6 are electrically and mechanically connected is manufactured.

[Anisotropic conductive film]
The anisotropic conductive film 7 is a thermosetting or ultraviolet curable adhesive and contains, for example, a film-forming resin, a thermosetting resin, a latent curing agent, a silane coupling agent, etc., as shown in FIG. The conductive particles 11 are dispersed in an ordinary binder resin 10 (adhesive), and this thermosetting adhesive composition is applied onto the base film 12 to be molded into a film.

  The base film 12 is formed by, for example, applying a release agent such as silicone to PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methlpentene-1), PTFE (Polytetrafluoroethylene), or the like.

  The film forming resin contained in the binder resin 10 is preferably a resin having an average molecular weight of about 10,000 to 80,000. Examples of the film forming resin include various resins such as an epoxy resin, a modified epoxy resin, a urethane resin, and a phenoxy resin. Among these, phenoxy resin is particularly preferable from the viewpoint of film formation state, connection reliability, and the like.

  It does not specifically limit as a thermosetting resin, For example, a commercially available epoxy resin, an acrylic resin, etc. are mentioned.

  The epoxy resin is not particularly limited. For example, naphthalene type epoxy resin, biphenyl type epoxy resin, phenol novolac type epoxy resin, bisphenol type epoxy resin, stilbene type epoxy resin, triphenolmethane type epoxy resin, phenol aralkyl type epoxy resin. Naphthol type epoxy resin, dicyclopentadiene type epoxy resin, triphenylmethane type epoxy resin and the like. These may be used alone or in combination of two or more.

  There is no restriction | limiting in particular as an acrylic resin, According to the objective, an acrylic compound, liquid acrylate, etc. can be selected suitably. For example, methyl acrylate, ethyl acrylate, isopropyl acrylate, isobutyl acrylate, epoxy acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, trimethylolpropane triacrylate, dimethylol tricyclodecane diacrylate, tetramethylene glycol tetraacrylate, 2-hydroxy- 1,3-diacryloxypropane, 2,2-bis [4- (acryloxymethoxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy) phenyl] propane, dicyclopentenyl acrylate, tricyclo Examples include decanyl acrylate, tris (acryloxyethyl) isocyanurate, urethane acrylate, and epoxy acrylate. In addition, what made acrylate the methacrylate can also be used. These may be used individually by 1 type and may use 2 or more types together.

  The latent curing agent is not particularly limited, and examples thereof include various curing agents such as a heat curing type and a UV curing type. The latent curing agent does not normally react, but is activated by various triggers selected according to applications such as heat, light, and pressure, and starts the reaction. The activation method of the thermal activation type latent curing agent includes a method of generating active species (cation, anion, radical) by a dissociation reaction by heating, etc., and it is stably dispersed in the epoxy resin near room temperature, and epoxy at high temperature There are a method of initiating a curing reaction by dissolving and dissolving with a resin, a method of initiating a curing reaction by eluting a molecular sieve encapsulated type curing agent at a high temperature, and an elution / curing method using microcapsules. Thermally active latent curing agents include imidazole, hydrazide, boron trifluoride-amine complexes, sulfonium salts, amine imides, polyamine salts, dicyandiamide, etc., and modified products thereof. The above mixture may be sufficient. Among these, a microcapsule type imidazole-based latent curing agent is preferable.

  Although it does not specifically limit as a silane coupling agent, For example, an epoxy type, an amino type, a mercapto sulfide type, a ureido type etc. can be mentioned. By adding the silane coupling agent, the adhesion at the interface between the organic material and the inorganic material is improved.

  Examples of the conductive particles 11 include any known conductive particles used in the anisotropic conductive film 7. Examples of the conductive particles 11 include particles of various metals and metal alloys such as nickel, iron, copper, aluminum, tin, lead, chromium, cobalt, silver, gold, metal oxide, carbon, graphite, glass, ceramic, Examples thereof include those in which the surface of particles such as plastic is coated with metal, or those in which the surface of these particles is further coated with an insulating thin film. In the case where the surface of the resin particle is coated with metal, examples of the resin particle include an epoxy resin, a phenol resin, an acrylic resin, an acrylonitrile / styrene (AS) resin, a benzoguanamine resin, a divinylbenzene resin, a styrene resin, and the like. Can be mentioned.

  In addition, the anisotropic conductive film 7 is good also as a structure which provides a cover film in the surface opposite to the surface where the base film 12 was laminated | stacked from viewpoints of the ease of handling, storage stability, etc. The shape of the anisotropic conductive film 7 is not particularly limited. For example, as shown in FIG. 5, the anisotropic conductive film 7 has a long tape shape that can be wound around the take-up reel 13 and is cut by a predetermined length. can do.

  Moreover, although the above-mentioned embodiment demonstrated as an example the adhesive film which shape | molded the thermosetting resin composition which contained the electroconductive particle 11 in the binder resin 10 suitably as an adhesive agent, it concerns on this invention. An adhesive agent is not limited to this, For example, it can be set as the structure which laminated | stacked the insulating adhesive layer which consists only of binder resin 10, and the electroconductive particle content layer which consists of binder resin 10 containing the electroconductive particle 11. FIG. . Moreover, an adhesive agent is not limited to the electroconductive adhesive film formed by such a film formation, It is good also as an electroconductive adhesive paste by which the electroconductive particle 11 was disperse | distributed to the binder resin composition. Further, the adhesive may be an insulating adhesive film in which the conductive particles 11 are not contained in the binder resin 10 or an insulating adhesive paste. The adhesive according to the present invention includes any of the forms described above.

[Connecting device]
Next, the connection device 20 that connects the flexible substrate 6 to the printed circuit board 1 will be described. As shown in FIG. 6, the connection device 20 is provided on the cradle 21, the elastic member 22 that supports the one surface 1 a of the printed circuit board 1, and the other surface 1 b of the printed circuit board 1 is anisotropic. And a pressing head 23 that heat-presses the flexible substrate 6 temporarily mounted via the conductive film 7.

  The cradle 21 supports the printed board 1 and the flexible board 6 that are thermally pressed by the pressing head 23 via the elastic member 22. An elastic member 22 is provided on the cradle 21.

  The elastic member 22 prevents damage, deformation, and peeling by buffering the pressure applied to the components such as the frame 3 and the semiconductor chip mounted on the one surface 1a of the printed circuit board 1 when heat is applied by the pressing head 23. The variation in the pressing force of the pressing head 23 against the flexible substrate 6 due to the difference in the uneven height of the frame 3 and other components mounted on the one surface 1a is eliminated. The elastic member 22 is made of an elastic material such as silicon rubber. For example, the elastic member 22 is formed in a substantially sheet shape, a substantially square shape, a substantially prismatic shape, a substantially cylindrical shape, or the like. Upper and lower surfaces 22a and 22b that contact each other are formed.

  As shown in FIG. 6, the printed board 1 may be arranged so that the side wall 3a of the frame 3 mounted on one surface 1a and the center of the upper surface 22a of the elastic member 22 are on the same line. preferable. Thereby, as shown in FIG. 7, the elastic member 22 can be supported with no gap to the side wall 3 a even when the printed circuit board 1 is thermally pressed by the pressing head 23. Pressure can be evenly distributed.

On the other hand, as shown in FIG. 8A, when the side wall 3a is disposed at a position biased to the outside of the upper surface 22a as shown in FIG. and the gap G ₁ is generated between the frame 3 is not distributed pressure against the side wall 3a, which may lead to deformation of the side wall 3a by pressure concentration. Further, the elastic member 22 protrudes from the one surface 1a of the printed circuit board 1 other than the frame 3, and there are many areas where the pressing force from the pressing head 23 is not generated, and the buffering action may be impaired.

  In addition, according to the connection device 1, an electronic component such as the flexible substrate 6 can be connected directly above the side wall 3 a by using the anisotropic conductive film 7. Is not required, the area of the printed circuit board 1 can be used effectively, and space can be saved. In addition, it is possible to prevent an increase in the size of the substrate by separately securing a connection point of the electronic component, avoiding the connection point of the shield can 2.

  In the present embodiment, the flexible substrate 6 is described as an example of an electronic component connected directly above the side wall 3a of the shield can 2. However, as the electronic component, in addition to the flexible substrate 6, an IC chip, a capacitor, a connector, and the like In addition, it includes all components that are connected to the printed circuit board 1 using the anisotropic conductive film 7.

  In addition, when the elastic member 22 is narrower than the pressing surface 23a of the pressing head 23 and is compressed by being pressed by the pressing head 23 in an uncompressed state before being pressed by the pressing head 23. In addition, it is preferably formed so as not to protrude from the pressing surface 23 a of the pressing head 23.

  When the connection part of the flexible substrate 6 or the connection part of the frame 3 is in the vicinity of the outer edge of the printed circuit board 1, the elastic member 22 also supports the vicinity of the outer edge of the printed circuit board 1, so that the pressure head 23 receives pressure. As shown in FIG. 9, the upper surface 22 a may protrude outward from the outer edge of the printed circuit board 1. At this time, the elastic member 22 is in sliding contact with the flexible substrate 6, pulling the flexible substrate 6 outward from the outer edge of the printed circuit board 1, and causing misalignment with the connection terminal portion 5.

  Therefore, the elastic member 22 is formed so as not to protrude from the pressing surface 23a of the pressing head 23 even when compressed by receiving pressure from the pressing head 23, thereby supporting the vicinity of the outer edge of the printed circuit board 1. Also in this case, as shown in FIG. 10, the repulsive force from the elastic member 22 that protrudes outward from the outer edge of the printed circuit board 1 is received by the pressing surface 23 a of the pressing head 23. Therefore, the flexible substrate 6 does not receive a force pulling outward from the protruding portion of the elastic member 22 from the outer edge of the printed circuit board 1, and can prevent misalignment.

  In addition, it is preferable that the elastic member 22 is 10-40 by Asker A hardness. If the hardness is higher than this, the pressing force applied by the pressing head 23 applied to the side wall 3a cannot be buffered, and the side wall 3a may be deformed.

  Further, the elastic member 22 is preferably set to be twice or more the height of the shield can 2, that is, the height of the side wall 3 a of the frame 3. This is because when the elastic member 22 is formed of silicone rubber, the repulsive force increases abruptly when the compression rate exceeds 50%. Therefore, for example, since the height of the shield can 2 used in a mobile phone or the like is about 1.0 to 2.0 mm, in this case, the elastic member 22 is preferably formed with a height of about 4 mm. .

  Moreover, it is preferable that the elastic member 22 has an area of the upper surface 22a when uncompressed larger than an area of the region where the connection terminal portion 5 of the printed circuit board 1 and the connection terminals 5a and 6a of the flexible circuit board 6 are provided. If the area of the upper surface 22a of the elastic member 22 that receives the pressing force of the pressing head 23 is smaller than the area of the connection terminals 5a and 6a of the flexible substrate 6, no uniform pressing force is applied to all the connection terminals. Connection failure may occur.

  The pressing head 23 heat-presses an electronic component anisotropically conductively connected to the other surface 1b of the printed circuit board 1 such as the flexible circuit board 6 at a predetermined pressure and temperature, and is supported up and down by a lifting mechanism (not shown). Has been. The pressing head 23 is provided with a pressing surface 23a for heating and pressing the electronic component.

  Further, as shown in FIGS. 6 and 7, the connection device 20 may be provided with a pressing member 25 that prevents the printed board 1 from being tilted when being pressed by the pressing head 23. The pressing member 25 prevents the printed circuit board 1 from tilting by contacting the other surface 1 b of the printed circuit board 1 when pressed by the pressing head 23.

  The pressing member 25 is provided on the side opposite to the outer edge to which the flexible substrate 6 of the printed circuit board 1 is connected, and is supported on the other surface 1b of the printed circuit board 1 so as to be movable up and down by a lifting mechanism (not shown). The pressing member 25 may be moved up and down in synchronization with the pressing head 23.

  By providing the pressing member 25, the connecting device 20 can prevent the printed circuit board 1 from tilting even when the flexible circuit board 6 is pressed in the vicinity of the outer edge of the printed circuit board 1, and the pressure of the pressing head 23 can be reduced. In addition, the connection terminals 5a and 6a of the connection terminal portion 5 can be uniformly applied, and the connection reliability can be improved. Further, by preventing the inclination of the printed circuit board 1, the repulsive force of the elastic member 22 on the one surface 1a of the printed circuit board 1 and the side wall 3a of the frame is also dispersed, and the deformation of the side wall due to the concentration of the repulsive force can be prevented. .

  In particular, the printed circuit board 1 is required to be mounted with high density, and the connection area between the connection terminal portion 5 and the flexible substrate 6 is narrowed. The pressing head 23 also has a narrow pressing surface 23a because it is necessary to narrow the connection area and prevent interference with other connecting parts. On the other hand, as the pressing force required for the heating and pressing using the anisotropic conductive film 7, a predetermined pressure is required regardless of the width of the connection region.

  And when pressing the outer edge of the printed circuit board 1 using the small size pressing head 23 in this way, the printed circuit board 1 is more easily inclined than when using a large size pressing head. When the printed circuit board 1 is tilted, the pressure of the pressing head 23 is concentrated immediately above the side wall 3a, the pressure applied to the entire connection terminals 5a and 6a is insufficient, the outflow of the binder resin 10 is insufficient, and the conductive particles 11 Insufficient clamping of the metal leads to an increase in conduction resistance. Therefore, the connection device 20 can reliably prevent the printed circuit board 1 from being tilted even when the small-sized pressing head 23 is used, and can improve the connection reliability. it can.

  Further, the connecting device 20 may be provided with a positioning member 26 for positioning the printed circuit board 1 as shown in FIGS. The positioning member 26 is provided at the same height as the printed board 1 in the vicinity of the outer edge to which an electronic component such as the flexible board 6 of the printed board 1 is connected. As a result, when the printed circuit board 1 is swung when the positioning member 26 is pressed by the pressing head 23 or the like, the positioning member 26 abuts on the outer surface to prevent the positional displacement of the printed circuit board 1, and the alignment displacement with the flexible substrate 6 is prevented. Can be prevented.

  Further, as shown in FIG. 7, the positioning member 26 also has the flexible substrate 6 and the elastic member 22 even when the elastic member 22 protrudes outward from the outer edge of the printed circuit board 1 when pressed by the pressing head 23. It is interposed between. Therefore, the positioning member 26 does not contact the flexible substrate 6 even when the elastic member 22 protrudes from the outer edge of the printed circuit board 1, and reliably prevents misalignment between the flexible substrate 6 and the printed circuit board 1. Can do.

[Connection process]
Next, a process of anisotropically conductively connecting the flexible substrate 6 to the other surface 1b of the printed circuit board 1 using the connection device 20 will be described. The printed circuit board 1 is preliminarily mounted with an electronic component such as a semiconductor chip on one surface 1a, and a frame 3 of a shield can 2 that covers the semiconductor chip or the like is connected by solder or the like as an EMC measure. The printed circuit board 1 is also provided with various electronic components such as a semiconductor chip and a capacitor on the other surface 1b, and a connection terminal portion 5 to which a flexible substrate 6 is connected is provided near the outer edge of the other surface 1b. It has been. The printed circuit board 1 is provided with a side wall 3 a of the frame 3 on the side opposite to the connection terminal portion 5.

  Then, after the anisotropic conductive film 7 is temporarily attached to the connection terminal portion 5, the printed board 1 is temporarily mounted with the flexible substrate 6 in alignment. In this state, the printed circuit board 1 is disposed on the connection device 20. At this time, the printed circuit board 1 aligns the side wall 3 a near the center of the upper surface 22 a of the elastic member 22. Next, the connection area between the connection terminal portion 5 and the flexible substrate 6 is heated and pressed from above the flexible substrate 6 by the pressing head 23.

  Thereby, the connection apparatus 20 can contact the elastic member 22 with respect to the side wall 3a without a gap, and can disperse the repulsive force evenly with respect to the frame 3. Therefore, the connection device 20 can prevent the side wall 3a from being deformed without the repulsive force of the elastic member 22 being concentrated on a specific portion of the frame 3.

  Further, when the connecting device 20 is formed so as not to protrude from the pressing surface 23a of the pressing head 23 even when the elastic member 22 is pressed by the pressing head 23, as shown in FIG. The repulsive force from the elastic member 22 that protrudes outward from the outer edge of the printed circuit board 1 is received by the pressing surface 23a. Therefore, the flexible substrate 6 does not receive a force pulling outward from the protruding portion of the elastic member 22 from the outer edge of the printed circuit board 1, and can prevent misalignment.

  In addition, the connection device 20 is provided with a pressing member 25 that prevents the printed board 1 from being tilted when pressed by the pressing head 23, so that the pressing member 25 is placed on the other surface 1 b of the printed board 1 when pressed by the pressing head 23. It is possible to prevent the printed circuit board 1 from tilting.

  Thereby, the connection apparatus 20 can apply the pressure of the press head 23 uniformly to both the connection terminals 5a and 6a of the flexible substrate 6 and the connection terminal part 5, and can improve connection reliability. Further, by preventing the inclination of the printed circuit board 1, the repulsive force of the elastic member 22 on the one surface 1a of the printed circuit board 1 and the side wall 3a of the frame is also dispersed, and the deformation of the side wall due to the concentration of the repulsive force can be prevented. .

  Further, the connecting device 20 is provided with a positioning member 26 for positioning the printed circuit board 1, thereby positioning the printed circuit board 1 when pressed by the pressing head 23, and an elastic member 22 protruding from the outer edge of the printed circuit board 1. Can be prevented from coming into contact with the flexible substrate 6 and misalignment between the flexible substrate 6 and the printed circuit board 1 can be reliably prevented.

  The pressing head 23 is heated and pressed from above the flexible substrate 6 at a curing temperature of the binder resin 10 for a predetermined pressure and a predetermined time. In the anisotropic conductive film 7, the binder resin 10 is fluidized and flows out between the connection terminals 5 a and 6 a of the flexible substrate 6 and the connection terminal portion 5, and the conductive particles 11 are transferred to the connection terminals 5 a and 6 a. It is pinched and cured in this state. Thereby, a connection body in which the printed board 1 and the flexible board 6 are electrically and mechanically connected is manufactured.

  The connection body inspects the mounting state and operation of the semiconductor chip, the frame body 3, the flexible substrate 6, etc., and finally the lid body 4 is fitted into the frame body 3. Thereby, electronic components, such as a semiconductor chip mounted on one surface 1a of the printed circuit board 1, are shielded.

  Next, examples of the present invention will be described. In the present embodiment, after adjusting the alignment by superimposing the flexible substrate 6 (FPC) on the other surface of the evaluation printed circuit board, to which the shield body frame 3 is connected on one surface, via the ACF, the pressing head 23 is used. The flexible substrate 6 was connected by applying heat and pressure to manufacture a connection body. And about this connection body, the presence or absence of a deformation | transformation of a frame, the presence or absence of the alignment shift | offset | difference of a printed circuit board and the flexible substrate 6, the inclination of the printed circuit board at the time of the pressurization with a press head, and the connection reliability of the flexible circuit board 6 were evaluated.

  The printed circuit board is 1.1 mm thick, and 35 μm thick gold-plated Cu wiring is formed at a pitch of 200 μm (L / S = 1/1).

  As the flexible substrate 6, NFX-2ABEPFE (25T) was used. In this flexible substrate, a gold-plated Cu wiring having a thickness of 12 μm is formed on a polyimide substrate having a thickness of 25 μm at a pitch of 200 μm (L / S = 1/1).

  The adhesive used to connect the flexible substrate 6 and the printed circuit board is ACF: DP3342MS manufactured by Dexerials Corporation. This ACF contains gold / nickel plating resin particles having an average particle diameter of 10 μm.

  Samples used in the examples and comparative examples are temporarily mounted on the printed circuit board by adjusting the alignment of the flexible circuit board 6 and the connection terminals 5a and 6a of the printed circuit board after temporarily attaching ACF on the connection terminal area of the printed circuit board. did. After the alignment adjustment, the flexible substrate 6 was connected on the printed circuit board using the pressing head 23. The heat and pressure conditions using ACF are 130 ° C., 2 MPa, and 6 seconds.

  In Example 1, as shown in FIG. 11, the printed circuit board is disposed in the vicinity of the center of the upper surface 22 a of the elastic member 22 so that the side wall 3 a of the frame 3 is aligned. The elastic member 22 was made of silicone rubber having a height of 30 mm and an Asker A hardness of 10 °. In the first embodiment, the elastic member 22 has a width before compression substantially equal to the pressing surface of the pressing head 23. In the first embodiment, the pressing member 25 and the positioning member 26 are not used.

  In the second embodiment, as shown in FIG. 12, the width of the elastic member 22 before compression is narrower than the width of the pressing surface 23 a of the pressing head 23, and the pressing is performed even when the pressing head 23 is pressed and compressed. The thing which does not protrude from the pressing surface 23a of the head 23 was used. Other conditions are the same as those in the first embodiment.

  In the third embodiment, as shown in FIG. 13, in addition to the configuration of the second embodiment, a pressing member 25 that prevents the printed board from being tilted when pressed by the pressing head 23 is provided.

  In the fourth embodiment, as shown in FIG. 6, in addition to the configuration of the third embodiment, a positioning member 26 for positioning the printed circuit board is provided.

  In Comparative Example 1, as shown in FIG. 14, the printed circuit board was supported by an elastic member over a wide range covering not only the connection area of the flexible circuit board 6 but also the entire frame 3, and heat-pressed with a pressing head. That is, in Comparative Example 1, the side wall 3a of the frame 3 is not aligned with the vicinity of the center of the upper surface of the elastic member. In the first embodiment, the pressing member 25 and the positioning member 26 are not used.

  Regarding the connection body in which the flexible substrate 6 is anisotropically conductively connected to the printed circuit board using the connection devices according to the above embodiments and comparative examples, the frame body is deformed and the printed circuit board and the flexible substrate 6 are not aligned. The inclination of the printed circuit board and the connection reliability of the flexible circuit board 6 during pressurization by the pressing head were evaluated. The evaluation results are shown in Table 1.

  Note that the deformation of the frame was visually observed, and the presence or absence of deformation in the side wall 3a and the beam portion extending between the side walls 3a was evaluated.

Further, the presence or absence of misalignment is shown in FIG. between the outer edge of the connecting terminal 6a is provided in the flexible substrate 6, it was evaluated by whether the gap G ₂ is generated.

  The inclination of the printed circuit board at the time of pressurization was evaluated by observing the connection location between the connection terminal portion 5 of the printed circuit board 5 and the flexible circuit board 6 with a microscope and indentation by the pressing head 23. That is, when the printed circuit board is tilted, the pressure of the pressing head 23 is concentrated immediately above the side wall 3a, and an indentation is observed only in the portion directly above the side wall 3a. Therefore, the inclination of the printed circuit board at the time of pressurization is determined depending on whether the indentation is observed over the entire connection portion between the connection terminal portion 5 and the flexible substrate 6 of the printed circuit board or only in a part of the connection portion. evaluated.

  As for the conductivity of the flexible substrate 6, for each connection structure, a conduction resistance value when a current of 1 mA is passed by a four-terminal method using a digital multimeter (part number: 34401A, manufactured by Agilent Technologies). (Initial) and the presence or absence of a short circuit was measured.

  As shown in Table 1, in Examples 1 to 4, the printed circuit board is arranged near the center of the upper surface 22a of the elastic member 22 so that the side wall 3a of the frame 3 is aligned. Even when the pressure is applied, the elastic member 22 can support the side wall 3a without any gap, and the pressure can be evenly distributed to the frame 3. Therefore, in Examples 1 to 4, no deformation of the frame 3 was observed.

  On the other hand, in Comparative Example 1, since the side wall 3a of the frame 3 is aligned at a position shifted from the center of the upper surface of the elastic member, a gap is generated between the side wall 3a and the frame 3, and the pressure on the side wall 3a is dispersed. The side wall 3a was deformed by pressure concentration. Moreover, with the pressure concentration to the specific location of a frame, the pressing force with respect to the whole connection location of the connection terminal part 5 of the printed circuit board 5 and the flexible substrate 6 was insufficient, resulting in inferior resistance value and short circuit.

  In contrast to Example 1 and Example 2, in Example 2, even when the elastic member 22 is compressed, the upper surface 22a does not protrude from the pressing surface 23a of the pressing head 23, and the elastic member 22 extends from the outer edge of the printed circuit board. Even in the case of sliding contact with the protruding flexible substrate 6, all the repulsive force at the protruding portion can be received by the pressing head 23. Therefore, in Example 2, the pulling force by the elastic member 22 is hardly applied to the flexible substrate 6, and it can be seen that the misalignment can be suppressed, which is advantageous compared to Example 1.

  Further, when the second embodiment and the third embodiment are compared, since the pressing member 25 is provided in the third embodiment, the printed circuit board may be inclined even when the flexible substrate 6 is pressed near the outer edge of the printed circuit board. Thus, the pressure of the pressing head 23 can be applied uniformly to the entire connection terminals 5a and 6a of the flexible substrate 6 and the connection terminal portion 5, and the connection reliability can be improved.

  Further, when the embodiment 3 and the embodiment 4 are compared with each other, the embodiment 4 includes the positioning member 26. Therefore, the positioning is achieved even when the printed circuit board is swung during the pressurization by the pressing head 23, and Even when the elastic member 22 protrudes from the outer edge portion of the printed circuit board, the elastic member 22 does not slidably contact the flexible substrate 6 because the positioning member 26 is interposed between the elastic substrate 22 and the flexible substrate 6. Therefore, according to the fourth embodiment, the misalignment between the printed circuit board and the flexible substrate 6 can be more reliably prevented as compared with the third embodiment.

DESCRIPTION OF SYMBOLS 1 Printed circuit board, 2 Shield can, 3 Frame body, 4 Cover body, 5 Connection terminal part, 5a Connection terminal, 6 Flexible substrate, 6a Connection terminal, 7 Anisotropic conductive film, 10 Binder resin, 11 Conductive particle, 12 Base film, 13 take-up reel, 20 connecting device, 21 cradle, 22 elastic member, 22a upper surface, 23 pressing head, 23a pressing surface, 25 pressing member, 26 positioning member

Claims (14)

A cradle,
An elastic member that is provided on the cradle and supports the one surface of the substrate having a frame-like member connected to the one surface in advance;
A pressing head for pressing an electronic component mounted on the other surface of the substrate via an adhesive;
The side wall of the frame member is aligned with the vicinity of the center of the support surface that supports one surface of the substrate of the elastic member,
An electronic component connecting method of pressing the electronic component mounted at a location on the other surface corresponding to a location where the side wall is provided by the pressing head.   The elastic member is narrower than the pressing surface of the pressing head when not compressed by the pressing head and is compressed by receiving pressure from the pressing head. The connection method according to claim 1, wherein the connection method does not protrude from the pressing surface.   The connection method according to claim 1, further comprising a pressing member that prevents the substrate from being tilted, wherein the pressing member is brought into contact with the other surface of the substrate when pressed by the pressing head.   A positioning member is provided near the outer edge of the substrate to which the electronic component is connected to position the substrate, and the positioning member is interposed between the electronic component and the elastic member when pressed by the pressing head. The connection method according to claim 1.   The connection method according to claim 1, wherein the elastic member has an Asker A hardness of 40 or less.   The connection method according to claim 1, wherein the elastic member has an area larger than a connection region of the electronic component to the substrate. A cradle,
An elastic member that is provided on the cradle and supports the one surface of the substrate having a frame-like member connected to the one surface in advance;
A pressing head for pressing an electronic component mounted on the other surface of the substrate via an adhesive;
The side wall of the frame member is aligned with the vicinity of the center of the support surface that supports one surface of the substrate of the elastic member,
The manufacturing method of the connection body which presses and connects the said electronic component mounted in the location of the said other surface corresponding to the location in which the said side wall was provided with the said press head. A cradle,
An elastic member that is provided on the cradle and supports the one surface of the substrate having a frame-like member connected to the one surface in advance;
A pressing head for pressing an electronic component mounted on the other surface of the substrate via an adhesive;
The elastic member supports a position corresponding to a mounting site of the electronic component on the substrate on which the electronic component is mounted at a location on the other surface corresponding to the location where the side wall is provided,
An electronic component connecting apparatus for pressing the electronic component by the pressing head.   The connection device according to claim 8, wherein a side wall of the frame-shaped member is aligned with a center of a support surface that supports one surface of the substrate of the elastic member.   The elastic member is narrower than the pressing surface of the pressing head when not compressed by the pressing head and is compressed by receiving pressure from the pressing head. The connecting device according to claim 8 or 9, wherein the connecting device does not protrude from the pressing surface.   The connection device according to any one of claims 8 to 10, further comprising a pressing member that prevents the substrate from tilting, wherein the pressing member is brought into contact with the other surface of the substrate when pressed by the pressing head.   A positioning member is provided near the outer edge of the substrate to which the electronic component is connected to position the substrate, and the positioning member is interposed between the electronic component and the elastic member when pressed by the pressing head. The connection device according to any one of claims 8 to 11.   The connection device according to claim 8, wherein the elastic member has an Asker A hardness of 40 or less.   The connection device according to claim 8, wherein the elastic member has an area larger than a connection region of the electronic component to the substrate.

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