JP4312148B2 - Relay board and three-dimensional wiring structure - Google Patents

Description

  The present invention relates to a relay board that relays a circuit module or the like on which an electronic component is mounted on a base circuit board, and a three-dimensional wiring structure using the relay board.

In recent years, in an electronic circuit device in which a resistor, a capacitor, a semiconductor element, and the like are mounted on an insulating circuit board, as the equipment becomes lighter and thinner, there is a strong demand for higher mounting density.
Conventionally, in this type of electronic circuit device, the high density of component mounting has been realized by reducing the wiring pitch and stacking a plurality of electronic circuit boards.

  For example, an electronic circuit device described in the following (Patent Document 1) has a structure in which a module circuit board 350 is stacked on a base printed circuit board 310 via a spacer 360 as shown in FIG.

  The spacer 360 has a structure that is temporarily fixed by spherical solders 380 and 390 that are electrically connected to the upper and lower surfaces through the via holes 320. The spacer 360 is collectively reflow soldered in a state of being temporarily fixed between the base printed circuit board 310 and the module circuit board 350. Reference numeral 330 denotes a surface mount component mounted on the module circuit board 350, and 340 denotes a semiconductor bare chip 340 mounted on the module circuit board 350.

  In addition, as shown in FIG. 14, the electronic circuit device described in (Patent Document 2) includes electronic circuit boards 410 and 430 through a heat-resistant elastic body 400 whose outer periphery is coated with a conductive material. It is a stacked structure. The heat-resistant elastic body 400 is soldered to the connection land 420 of one electronic circuit board 410, and is crimped to the connection land 440 of the other electronic circuit board 430 with a clip, a bolt 470, or the like. 450 is a surface mount component, and 460 is a semiconductor bare chip.

  Further, in the electronic circuit device described in the following (Patent Document 3), the module circuit board 500 is mechanically and electrically connected to the mother board 540 via the connection chip 550 as shown in FIG. The IC package 510, 520, and 530 are passive components.

  In addition, an electronic circuit device described in the following (Patent Document 4) includes a lens 660, an optical filter 670, and a semiconductor imaging device 610 on a three-dimensional printed circuit board 600, as shown in FIGS. The lens 660 is integrated on the optical axis. The three-dimensional printed circuit board 600 has a wiring pattern 650 for connecting the semiconductor imaging device 610 and the chip component 615. Reference numeral 640 denotes a printed circuit board on which the three-dimensional printed circuit board 600 is mounted by soldering.

  Furthermore, the electronic circuit device described in the following (Patent Document 5) includes a semiconductor imaging device 610 and an infrared filter 680 on a three-dimensional printed circuit board 600 as shown in FIGS. 17 (a), (b), and (c). The three-dimensional printed circuit board 600 is mounted and mounted on the circuit integrated printed circuit board 640.

In addition to the above, there is a method of joining using a connector which is a general connection component.
JP 2001-177235 A JP 2001-267715 A Japanese Patent Laid-Open No. 6-260736 JP 2001-245186 A JP 2000-341666 A

  As mobile terminal devices become more advanced and lighter, thinner, and smaller, planar electronic circuit devices have limitations in improving mounting density by reducing the connection pitch and reducing the spacing between adjacent components. . For this purpose, module circuit boards are three-dimensionally stacked to increase the density.

  The spacer 360 of (Patent Document 1) and the connecting chip 550 of (Patent Document 3) are three-dimensional via conductive vias or via holes 320 that connect lands formed on the upper and lower surfaces of the circuit board and corresponding lands. Connected.

  Further, when a clip 470, a bolt, or the like is used for fixing between the stacked module circuit boards in (Patent Document 2), the area occupied by the fixing and connecting member increases, so that the mounting area decreases. Moreover, the area of the connection connector which occupies for the connection of a module circuit board is increasing by the increase in the number of connection terminals between module circuit boards. Therefore, there is a problem that the mounting density cannot be increased due to an increase in the connection area between the module circuit boards.

  Further, the three-dimensional printed circuit board 600 of (Patent Document 4) and (Patent Document 5) discloses a three-dimensional wiring structure of the image sensor 610 and is connected to the printed circuit board 640 in three dimensions via the solder 620. is there. However, there is a problem that connection reliability cannot be increased simply by soldering the tip of the land electrode 630 of the three-dimensional printed circuit board 600 formed on the substrate surface and the wiring 650 of the printed circuit board 640.

  An object of the present invention is to solve the above-mentioned conventional problems and to provide a relay substrate that can realize high-density mounting and high connection reliability.

The relay board according to claim 1 of the present invention includes a relay board body interposed between the first circuit board and the second circuit board, and a surface of the relay board body on the first circuit board side. To the second circuit board side surface corresponding to the electrical connection location, and the relay board body is in the vicinity of the end of the board connection wiring. Forming a recess in each of a corner continuous from the surface on the side of the circuit board to the side and a corner connected to the side of the side of the second circuit board near the end of the board connection wiring; The end portion of the substrate connection wiring extends along the recess, the end treatment material is filled in the recess, and the end portion of the substrate connection wiring is embedded in the end treatment material.

The relay board according to claim 2 of the present invention is the relay board according to claim 1, wherein the relay board body in the middle of the board connection wiring is connected to a corner portion continuous from the upper surface to the side surface of the relay board body near the middle of the board connection wiring. A recess is formed in at least one of the lower surface of the substrate and a corner portion connected to the side surface portion, a substrate connection wiring is formed along the recess, the corner processing material is filled in the recess, and the corner portion of the substrate connection wiring is the corner portion. It is embedded in the processing material.

  The relay board according to claim 3 of the present invention is a relay board main body interposed between the first circuit board and the second circuit board, and a surface of the relay board main body on the first circuit board side. To the second circuit board side surface corresponding to the electrical connection location, and the relay board body is connected to the first circuit board side surface from the side surface portion. At least one of a corner portion connected to the side surface and a corner portion continuous from the surface on the second circuit board side to the side surface portion is formed on an inclined surface having a corrugated curved surface; The part and the corner are pasted along the slope having the corrugated curved surface.

  According to a fourth aspect of the present invention, there is provided a three-dimensional wiring structure including the relay board according to any one of the first to third aspects interposed between the first circuit board and the second circuit board. The first and second circuit boards are three-dimensionally connected.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a relay board, in which a circuit board is connected in the vertical direction and a first resin is injection-molded using a first mold into a board shape to be relayed, and a three-dimensional molded body is formed. Forming first
In the second step, a second resin is used to injection-mold the fourth resin in addition to the step of forming the substrate connection wiring for electrically connecting the connection land electrode and the connection land electrode to the side surface. And the process of
A third step of forming a plating catalyst on the substrate connection wiring portion that electrically connects the connection land electrode portions on the upper and lower surfaces of the three-dimensional molded body and the connection land electrodes on the side surfaces; A fourth step of removing and plating the resin, and a fifth step of covering the end portion of the connection land electrode so as to be embedded by injection molding of the second resin using a third mold. It is characterized by comprising.

According to a sixth aspect of the present invention, there is provided the relay substrate manufacturing method according to the fifth aspect , wherein the first insulating resin and the second resin in which the end portion of the land electrode of the relay substrate is formed in an S-curve shape. And a step of molding so as to be embedded between the two.

According to a seventh aspect of the present invention, there is provided a relay board manufacturing method according to the fifth aspect of the present invention, in which secondary wiring is performed so that the wiring in the corner portion connected to the side surface portion from the land electrode on the upper and lower surfaces of the relay substrate is embedded in the resin. It is characterized by comprising the step of:

  The relay board according to the present invention is provided with the terminal connection wiring provided on the relay board main body embedded in the terminal treatment material, so that the relay board is not easily peeled off even by a thermal shock or a drop impact, and thus has high reliability. realizable.

  In addition, since the end part of the board connection wiring is pasted along the slope with the corrugated curved surface provided in the relay board body, it is hard to be peeled off even by thermal shock or drop impact, so high reliability can be realized .

  Even if the relay board body is embedded in the corner processing material corresponding to the corner part of the board connection wiring as well as the end part of the board connection wiring, or is attached to a slope with a corrugated curved surface, High adhesion can be realized by improving the adhesion between the resin, the land electrode end and the corner, and suppressing the shear stress and the peeling stress by the corrugated curved surface.

  In addition, each electronic component mounted on the first circuit board or the second circuit board can be electrically connected up and down with a relay board in the shortest distance, and the frequency characteristics of the three-dimensional wiring structure and the high-speed signal Improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1 and 2 show a three-dimensional wiring structure using a relay board according to the first embodiment of the present invention. 1 is a cross-sectional view taken along line AA ′ of FIG.

  The three-dimensional wiring structure shown in FIG. 1 has a three-dimensional connection structure (3 in which a first circuit board 1 and a second circuit board 2 are electrically and mechanically connected by a bonding layer 4 via a relay board 3. Dimension module).

  The first circuit board 1 has electronic components 16 (including a semiconductor device) mounted on both sides and is provided with lead terminal electrodes 11 from the electronic components to the outside. It may be a part of a connection wiring board or a functional board connected to the circuit board.

  The second circuit board 2 has electronic components (including a semiconductor device) mounted on both sides and is provided with lead-out terminal electrodes 12 from the electronic components to the outside, but may have such a module structure. However, it may be a part of a so-called motherboard.

  Although not shown in the drawing, the first and second circuit boards 1 and 2 are composed of a conductive via and an insulating base material. Each circuit board is a double-sided board or a multilayer wiring board configured by mounting electronic components 16 (including a semiconductor device).

  Each electronic component 16 is a general passive component such as a semiconductor element such as an IC or LSI, a semiconductor package, a resistor, a capacitor, or an inductor. It is also possible to mount a bare chip-shaped electronic component by flip chip mounting or wire bonding connection.

  Further, the relay board 3 having a connector function for connecting the first circuit board 1 and the second circuit board 2 is an annular relay having a through hole 3c formed in the center as shown in FIG. Substrate connection wiring 10 is required at a predetermined interval from the upper surface 13 on the back surface side of the first circuit board 1 to the lower surface 14 on the upper surface side of the second circuit board 2 at necessary portions of the substrate body 3a. The number is formed. Specifically, the annular relay substrate body 3a has a planar shape of 20 mm to 30 mm, a thickness: h1 = 1.0 mm to 2.0 mm, and a width: w1 = 0.5 mm to 1.0 mm.

  In FIG. 2, the first and second circuit boards 1 and 2 positioned above and below the relay board 3 are abbreviated and indicated by virtual lines. Further, a part of the relay board 3 is shown by a solid line so that it can be easily understood even if it is not visible in FIG. Specifically, a portion along the inner wall surface of the through hole 3c of the relay substrate body 3a and a portion along the lower surface 14 in the board connection wirings 10 arranged on the near side in FIG. The board connection wirings 10 arranged on the back side in FIG. 2 are configured in the same manner as the board connection wirings 10 on the front side.

  With this configuration, the lead terminal electrode 11 of the first circuit board 1 is bonded to the land electrode 5a of the board connection wiring 10 located on the upper surface 13 of the relay board body 3a via the bonding layer 4. The lead-out terminal electrode 12 of the second circuit board 2 is joined to the land electrode 5b of the board connection wiring 10 located on the lower surface 14 of the relay board body 3a via the joining layer 4.

Here, the bonding layer 4 uses any of various bonding members such as solder, solder balls, microconnectors, heat seal connectors, anisotropic conductive films, and conductive adhesives.
Thus, according to the three-dimensional wiring structure using the relay board 3, the first and second circuit boards 1 and 2 correspond to the inside of the through hole 3c formed at the center of the relay board 3. In addition, since the electronic component 16 can be mounted, more circuit components can be taken in while securing the connection area between the first and second circuit boards 1 and 2, so that high-density mounting can be realized.

  Further, by connecting the electronic component 15 mounted on the first circuit board 1 or the second circuit board 2 through the relay board 3 at the shortest distance, the frequency characteristics of the three-dimensional wiring structure can be improved, and the signal Speeding up is possible, and high-speed operation of electronic devices can be realized.

  Further, a recess 3b is formed in the relay board body 3a at a position corresponding to the end of the board connection wiring 10 of the relay board 3, and the end of the board connection wiring 10 extends along the inside of the recess 3b. Each recess 3b is filled with an insulating resin end treatment material 9.

  Since the end portion of the substrate connection wiring 10 is embedded in the end treatment material 9 in this way, the peeling stress acting between the upper and lower substrates and the land electrode due to the thermal shock or the drop impact, the peeling due to the shear stress, and the crack initiation are suppressed or buffered. And high reliability can be realized.

  The first and second circuit boards 1 and 2 can be general resin boards, inorganic boards, or composite boards. In particular, a glass epoxy substrate, a substrate using an aramid base material, a build-up substrate, a glass ceramic substrate, an alumina substrate, or the like is preferable.

  For the relay substrate body 3a of the relay substrate 3, a general thermoplastic resin, thermosetting resin, or the like is used. In the case of a thermoplastic resin, it can be formed into a desired shape by injection molding, cutting, laser processing, or chemical processing. Moreover, in the case of a thermosetting resin, it can be made into a desired shape by cutting the cured product. As thermoplastic resins, PPA (polyphthalamide), LCP (liquid crystal polymer), TPX (polymethylbenten), PEI (polyamideimide), PPS (polyphenylene sulfide), PES (polyethersulfone), PSF (polysulfone) ), PBT (polybutylene terephthalate), PA (polyamide) -based, ester-based resin, SPS, PPO, PPE, and thermosetting resin, it is preferable to use a normal epoxy resin or the like. By using a resin material having a low Young's modulus for the relay substrate 3, it is possible to relieve shear stress and peeling stress caused by the difference in thermal expansion coefficient between the first and second circuit substrates 1 and 2.

  Further, the substrate connection wiring 10 of the relay substrate 3 is manufactured by a printing method using a conductive paste, a metal foil attached to the substrate surface, or a method of laser processing a plating layer deposited on the substrate surface. . As the three-dimensional wiring material, metals such as Ag, Sn, Zn, Pd, Bi, Ni, Au, Cu, C, Pt, Fe, Ti, and Pb are used.

The end treatment material 9 is selected from the same material as the relay substrate body 3a or a material having good adhesion to the relay substrate body 3a.
The relay board 3 in FIG. 1 is exaggerated to show the inside in detail, but is basically not different from the relay board 3 in FIG. The same applies to the following embodiments.

  In FIG. 1 and FIG. 2, the end located on the upper side 13 of the relay board body 3a at the end of the board connection wiring 10 and the end located on the lower side 14 of the relay board body 3a are defined as the relay board body. Although it embedded in the terminal treatment material 9 with which the separate recessed part 3b formed in 3a was filled, this is an edge part located in the upper side 13 of the relay substrate main body 3a in the edge part of the board | substrate connection wiring 10 as shown in FIG. And the end located on the lower side 14 of the relay board body 3a may be embedded in the end treatment material 9 filled in the common recess 3d formed in the relay board body 3a. Can be expected. In particular, in the case of FIG. 3, as shown in FIGS. 1 and 2, the end treatment material 9 filled in the recess 10 on the upper side 13 of the relay board body 3a and the end filled in the recess 10 on the lower side 14 of the relay board body 3a. Since it is not necessary to increase the resin molding accuracy required for separating the treatment material 9, it is possible to reduce the cost.

In each of the above embodiments, the circuit wiring and the electrical characteristics may be taken into consideration regardless of whether the substrate wiring electrode 10 is inside or outside the relay substrate 3.
Further, in each of the above-described embodiments, both the end portion on the first circuit board 1 side and the end portion on the second circuit board 2 side of the substrate connection wiring 10 are used as the end treatment material 9. Although embedded, at least one of the end part on the first circuit board 1 side and the end part on the second circuit board 2 side is expected to have some effect. it can.

(Second Embodiment)
FIG. 4 and FIG. 5 show a three-dimensional wiring structure using a relay board in (second embodiment) of the present invention. 4 is a cross-sectional view taken along line AA ′ of FIG.

  The shape of the relay substrate 3 is different from that of the first embodiment. Others are the same. Specifically, in FIG. 1, only the end portions of the respective board connection wirings 10 are embedded in the end treatment material 9, but in FIG. 4, the connection from the upper surface 13 of the relay substrate body 3a to the side surface portion of the through hole 3c is continued. Second recesses 3e are respectively formed at the corners and corners continuous from the lower surface 14 of the relay substrate body 3a to the side surfaces of the through holes 3c, and the substrate connection wirings 10 are formed along the second recesses 3e. The second recess 3 e is filled with a resin as the corner portion treatment material 8, and the corner portion 7 of the substrate connection wiring 10 is embedded in the corner portion treatment material 8. The corner treatment material 8 and the end treatment material 9 are the same or different resins depending on the part.

According to this configuration, it is possible to realize high reliability that is more resistant to thermal shock and drop impact.
In this embodiment, the second recess is formed in both the corner portion 7 of the relay board 3 on the first circuit board 1 side and the corner portion 7 of the relay board 3 on the second circuit board 2 side. 3e is formed, and both of the second recesses 3e are filled with the corner treatment material 8, but the corner portion 7 on the side of the first circuit board 1 of the relay board 3 and the second circuit of the relay board 3 are formed. A second concave portion 3e is formed in at least one of the corner portion 7 on the substrate 2 side, and the corner portion 7 of the substrate connection wiring 10 is processed by the corner portion treatment by filling the second concave portion 3e with a corner portion treatment material 8. Some effects can be expected by embedding in the material 8.

  4 and 5, the end portion of the board connection wiring 10 that is located on the upper side 13 of the relay board body 3a and the end portion that is located on the lower side 14 of the relay board body 3a are the relay board body. Although it embedded in the terminal treatment material 9 with which the separate recessed part 3b formed in 3a was filled, this is an edge part located in the upper side 13 of the relay substrate main body 3a in the edge part of the board | substrate connection wiring 10 as shown in FIG. And the end located on the lower side 14 of the relay board body 3a may be embedded in the end treatment material 9 filled in the common recess 3d formed in the relay board body 3a. Can be expected. In particular, in the case of FIG. 6, as shown in FIGS. 4 and 5, the end treatment material 9 filled in the recess 10 on the upper side 13 of the relay board body 3a and the end filled in the recess 10 on the lower side 14 of the relay board body 3a. Since it is not necessary to increase the resin molding accuracy required for separating the treatment material 9, it is possible to reduce the cost.

(Third embodiment)
FIG. 7 is a schematic cross-sectional view of a three-dimensional wiring structure using a relay board according to the (third embodiment) of the present invention. The same components as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In the first embodiment shown in FIG. 1, the end of the substrate connection wiring 10 on the first circuit board 1 side and the end on the second circuit board 2 side are connected to the end treatment material. In order to embed it in the recess 9, the recess 3b formed in the relay substrate body 3a is filled with the end treatment material 9, but in FIG. 7, the recess 3b is not formed in the relay substrate body 3a, and an elastic bonding material is provided. 17 is bonded to the surface of the relay substrate body 3a, and the end portions of the board connection wiring 10 on the first and second circuit boards 1 and 2 side are embedded in a bonding material 17 as a terminal treatment material. . In FIG. 7, the cross-sectional shape of the relay substrate body 3a is formed in an octagon so that the bonding material 17 can be easily bonded.

  Note that the bonding material 17 may be a resin having a lower Young's modulus than the relay substrate body 3 a and the end treatment material 9. For example, a silicone resin such as room temperature vulcanization (RTV) is used. Others are the same as those in the first embodiment. More specifically, (liquid crystal polymer LCP, PPA): 13.8 to 17.0 GPa is used as the relay substrate body 3a and the end treatment material 9, and RTV silicone: 0.5 to 5 Pa or a low elastic epoxy as the bonding material 17 is used. : 10-100 MPa is used.

  Since the end of the substrate connection wiring 10 is covered with the bonding material 17 and buried in this way, the shear stress and peeling acting between the first and second circuit boards 1 and 2 and the upper and lower land electrodes 5 due to a thermal shock or a drop impact. It is possible to suppress or buffer the occurrence of peeling or cracking due to stress, and high reliability can be realized.

(Fourth embodiment)
FIG. 8 is a schematic cross-sectional view of a three-dimensional wiring structure using a relay board according to the (fourth embodiment) of the present invention. The same components as those in FIGS. 1, 4 and 7 will be described with the same reference numerals.

  In FIG. 4 in (second embodiment), the end treatment material 9 is filled and embedded in the recess 3b provided in the relay substrate body 3a. In this (fourth embodiment), the relay substrate body 3a is embedded. As shown in FIG. 8, the cross-sectional shape is formed on the inclined side 3f at the position corresponding to the end of the substrate connection wiring 10 as in the case of FIG. The end of the substrate connection wiring 10 is buried by bonding the resin 17 on the inclined side 3f. Furthermore, the second recesses 3e are respectively formed at the corners that are continuous from the upper surface 13 of the relay substrate body 3a to the side surface of the through hole 3c and the corners that are connected from the lower surface 14 of the relay substrate body 3a to the side surface of the through hole 3c. The substrate connection wiring 10 is formed along the second recess 3e, the corner processing material 8 is filled in the second recess 3e, and the corner portion 7 of the substrate connection wiring 10 is used as the corner processing material 8. The point of burying is the same as FIG.

  With this configuration, not only the high reliability described in the (second embodiment) but also low cost and shortened delivery time can be realized. Specifically, it is not necessary to make the second metal mold 19 shown in FIG. 12 to be described later to form the end treatment material 9, and the cost can be reduced and the delivery time can be shortened.

(Fifth embodiment)
FIG. 9 is a schematic cross-sectional view of a three-dimensional wiring structure using a relay board according to the (fifth embodiment) of the present invention. The same components as those in FIG. 7 will be described with the same reference numerals.

  In the (third embodiment) shown in FIG. 7, the end of the board connection wiring 10 is embedded in the bonding material 17 bonded to the inclined side 3f of the relay board main body 3a. In the embodiment, as shown in FIG. 9, the inclined side 3 f is formed on the wavefront curved surface 20. Further, the corner portion of the relay substrate main body 3 a is also formed on the wavefront curved surface 20, and both the end portion and the corner portion of the substrate connection wiring 10 are pasted along the wavefront curved surface 20.

  According to this configuration, the adhesion between the end portion of the substrate connection wiring 10 and the corner portion 7 is improved, and the corrugated curved surface is used, so that a shear stress or a peeling stress generated in the vicinity of the land electrode 5 due to a thermal shock or a drop impact. By suppressing the above, high reliability can be realized.

  In each of the above-described embodiments, the relay board body 3a includes the corner portion that continues from the surface on the first circuit board 1 side to the side surface portion, and the side surface from the surface on the second circuit board 2 side. Both the corners connected to the part are formed on a slope having a corrugated curved surface, and the end part of the substrate connection wiring 10 is pasted here, but it is connected from the surface on the first circuit board 1 side to the side part. At least one corner portion of the corner portion and the corner portion continuous from the surface on the second circuit board 2 side to the side surface portion is formed on an inclined surface having a corrugated curved surface, and an end portion of the substrate connection wiring 10 Some effect can be expected by pasting along the slope having the corrugated curved surface.

  In each embodiment of the present invention, the relay board having a quadrangular shape and the configuration in which the first circuit board and the second circuit board are disposed on the upper and lower surfaces of the relay board have been described. The first circuit board and the second circuit board may be relayed by a relay board having a substantially L shape, a triangle shape, a circular shape, or the like.

  Moreover, although the relay board | substrate 3 of each embodiment of this invention was the shape which has the through-hole 3c in the center, the relay board | substrate which does not have the through-hole 3c may be sufficient. Specifically, an electronic component may be mounted in the recess by forming a recess partway in the middle of the relay substrate 3 and not having the through hole 3c.

Further, it goes without saying that the embodiments described in the present invention can be applied to each other, and are not limited to these embodiments.
(Sixth embodiment)
10A to 10F show a method for manufacturing a three-dimensional wiring structure of the present invention.

The three-dimensional wiring structure of FIG. 6 is manufactured in the following process.
First, the bonding layer 4 is formed by printing or the like on the desired terminal electrode 15 on which the electronic component 16 and the relay board 3 of the first circuit board 1 are mounted (FIG. 10A). The bonding layer 4 may be formed by a plating method, a printing method (printing using the metal plate 23 or a screen), a dispensing method, or the like.

  Next, the electronic component 16 and the relay substrate 3 are aligned and placed on the first circuit board 1 on which the bonding layer 4 is formed. At this time, when the electronic components 16 are mounted on both surfaces of the first circuit board 1, the electronic components 16 are placed on the upper (front) side of the first circuit board 1 and then reversed. Then, the electronic component 16 and the relay substrate 3 are placed on the lower (back) side (FIG. 10B).

  Next, the first circuit board 1 on which the electronic component 16 and the annular relay substrate 3 are placed is melted or cured by the heat process such as reflow or a curing furnace to melt the electronic component 16 and the relay substrate. 3 are electrically joined (FIG. 10C). Alternatively, the front and back surfaces may be combined by performing a thermal process.

Next, the bonding layer 4 is formed by printing or the like on the desired terminal electrode 15 on which the electronic component 16 and the relay substrate 3 of the second circuit board 2 are mounted (FIG. 10D).
Next, the electronic component 15 and the first circuit board 1 with the relay board 3 are positioned and placed on the second circuit board 2 on which the bonding layer 4 is formed. At this time, when the electronic component 16 is mounted on both surfaces of the second circuit board 2, after the electronic component 16 is placed on the upper (front) side of the second circuit board 2, the electronic component 16 is reversed. The electronic component 16 and the first circuit board 1 with the relay board 3 are placed on the lower (back) side (FIG. 10E). Again, the back side may be passed through the heat step first.

  Finally, the second circuit board 2 on which the electronic circuit board 15 and the first circuit board 1 with the relay board 3 are placed is melted or hardened by a heat process such as reflow or a curing furnace so that the electronic circuit board 2 is melted or hardened. 16 and the first circuit board 1 with the relay board 3 are electrically joined (FIG. 10F).

  By adopting such a manufacturing method, the first circuit board 1 and the second circuit board 2 are separately made into module boards and then connected, so that the characteristic inspection of each module board can be easily performed.

(Seventh embodiment)
11 (a) to 11 (i) show another method for manufacturing a three-dimensional wiring structure according to the present invention.
The three-dimensional wiring structure of FIG. 11 is manufactured by the following process.

First, the bonding layer 4 is formed by printing or the like on the desired terminal electrode 15 on which the electronic component 16 and the relay substrate 3 of the first circuit board 1 are mounted (FIG. 11A).
Next, the electronic component 16 and the relay substrate 3 are aligned and placed on the first circuit board 1 on which the bonding layer 4 is formed (FIG. 11B).

  Next, the first circuit board 1 on which the electronic component 16 and the annular relay substrate 3 are placed is melted or cured by a thermal process such as reflow or a curing furnace to melt or cure the electronic component 16 and the relay substrate 3. Are electrically joined (FIG. 11C).

Next, the bonding layer 4 is formed by printing or the like on the desired terminal electrode 15 on which the electronic component 16 and the relay substrate 3 of the second circuit board 2 are mounted (FIG. 11D).
Next, the electronic component 16 is positioned and placed on the second circuit board 2 on which the bonding layer 4 has been formed (FIG. 11E).

  Next, the second circuit board 2 on which the electronic component 16 is placed is melted or cured by a heat process such as reflow or a curing furnace to electrically join the electronic component 16 and the relay substrate 3. (FIG. 11 (f)).

  Next, a conductive material 21 such as an anisotropic conductive film sheet such as ACF or a conductive adhesive is applied or applied on the terminal electrode 15 of the second circuit board 2 with the electronic component 16 (FIG. 11 (g )).

Next, the relay board 3 bonded to the first circuit board 1 is placed after being aligned with the second circuit board 2 (FIG. 11 (h)).
Finally, the second circuit board 2 on which the first circuit board 1 with the relay board 3 is placed is held in a pressurized and heated state, or at least a heat process such as a soft beam or a curing furnace, or ultraviolet rays (UV rays). The first conductive circuit board 1 and the second printed circuit board 2 are electrically bonded to each other through the relay substrate 3 by curing the conductive material by the light irradiation step (FIG. 11 (i)).

  By making such a manufacturing method, the first circuit board 1 and the second circuit board 2 are separately made into module boards and then connected, so that the characteristic inspection of each module board can be easily performed, Since the connection temperature between the first circuit board 1 and the second circuit board 2 can be lowered, the temperature load on the electronic component 16 and the relay board 3 to be mounted, the warp of the circuit board and the relay board 3, Connection instability due to undulation is suppressed, and a connection structure with high electrical and mechanical connection reliability can be realized.

(Eighth embodiment)
12A to 12E show a method for manufacturing the relay substrate 3 of the present invention.
The relay substrate 3 used for the three-dimensional wiring structure of FIG. 6 is manufactured in the following process.

12A to 12E, the first mold is 18, the second mold is 19, the fourth resin is 25, and the third mold is 26. Here, each is shown with a virtual line.
First, the first and second circuit boards 1 and 2 are connected in the vertical direction, and the relay board main body 3a is formed in the shape of the board to be relayed, and the first insulating resin is injection molded using the first mold 18. (FIG. 12A).

  Next, the 4th resin 25 is inject | emitted using the 2nd metal mold | die 19 except the part which forms the board | substrate connection wiring 10 which electrically connects between the connection land electrode 5 and the connection land electrode 5 on a side surface. Molding is performed (FIG. 12B).

  Next, a plating catalyst 27 is formed on the connection land electrode 5 on the upper and lower surfaces of the relay substrate body 3a and on the side surface of the substrate connection wiring 10 that electrically connects the connection land electrodes 5 (FIG. 12). (C)).

  Next, the fourth resin 25 is removed and plating is performed (FIG. 12D). The fourth resin 25 serves as a resist and can be melted by weak alkali, weak acid, or heating. For example, when biodegradable polylactic acid resin (PLLA) is used, dissolution can be performed with weak alkaline hot water.

Finally, using the third mold 26, the end treatment material 9 is injection-molded to cover the end portion 6 of the connection land electrode 5 (FIG. 12E).
By adopting such a manufacturing method, the end portion 6 in the vicinity of the land electrode 5 can be suppressed and alleviated from shear stress and peeling stress due to thermal shock and drop impact, so electrical and mechanical connection reliability can be achieved. High connection relay board 3 can be realized.

  Further, after the end portion 6 of the land electrode 5 of the relay substrate 3 is formed on the corner portion processing material 8 formed in an S-curve shape, the manufacturing method is performed so as to be embedded in the end processing material 9. In this way, it is possible to suppress or alleviate the shear stress or peeling stress caused by the thermal shock or the drop impact.

  Further, by adopting a manufacturing method in which the wiring of the corner portion 7 connected to the side surface portion from the land electrodes 5 on the upper and lower surfaces of the relay substrate 3 is secondarily formed so as to be embedded in the end treatment material 9, more thermal shock and drop impact can be achieved. It can be suppressed and relaxed from shearing stress and peeling stress.

  The three-dimensional wiring structure of the present invention is a three-dimensional connection structure in which a first circuit board and a second circuit board are connected via a relay board, and the circuit boards can be joined and high-density mounting can be realized. Therefore, the present invention can be widely used in various mobile devices such as mobile phones and the like that are highly functional, multifunctional, and compact, and mobile terminal devices such as door remote controllers for automobiles.

Schematic cross-sectional view of the three-dimensional wiring structure in the first embodiment of the present invention Schematic perspective view of relay board of same three-dimensional wiring structure Schematic sectional view of a three-dimensional wiring structure in another example of the first embodiment of the present invention Schematic sectional view of the three-dimensional wiring structure in the second embodiment of the present invention Schematic perspective view of relay board of same three-dimensional wiring structure Schematic sectional view of a three-dimensional wiring structure in another example of the second embodiment of the present invention Schematic sectional view of a three-dimensional wiring structure according to a third embodiment of the present invention Schematic sectional view of a three-dimensional wiring structure according to a fourth embodiment of the present invention Schematic sectional view of a three-dimensional wiring structure according to a fifth embodiment of the present invention Process drawing of the manufacturing method of the three-dimensional wiring structure in the 6th Embodiment of this invention Process drawing of the manufacturing method of the three-dimensional wiring structure in the 7th Embodiment of this invention Process drawing of the manufacturing method of the relay substrate in the eighth embodiment of the present invention Sectional drawing of the electronic circuit device of (patent document 1) Sectional drawing of the electronic circuit device of (patent document 2) Sectional drawing of the electronic circuit device of (patent document 3) Sectional drawing of the electronic circuit device of (patent document 4) Sectional drawing of the electronic circuit device of (patent document 5)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st circuit board 2 2nd circuit board 3 Relay board 3a Relay board main body 3b Recessed part 3c Through-hole 3d Recessed part 3e Recessed part 3f Inclined side 4 Bonding layer 5 Land electrode 6 End part of board connection wiring 7 Corner part 8 Corner part Treatment material 9 Terminal treatment material 10 Substrate connection wiring 11 Lead terminal electrode 12 Lead terminal electrode 13 Upper surface 14 Lower surface 15 Terminal electrode 16 Electronic component 17 Bonding material 18 First die 19 Second die 20 Wave surface 27 Curved surface Metal plate 24 Squeegee 25 Fourth resin 26 Third mold

Claims (8)

A relay board body interposed between the first circuit board and the second circuit board;
Board connection wiring formed corresponding to the electrical connection location from the surface on the first circuit board side of the relay board body to the surface on the second circuit board side, and the relay board body A corner portion extending from the surface on the first circuit board side to the side surface portion in the vicinity of the end portion of the substrate connection wiring, and from the surface on the second circuit board side in the vicinity of the end portion of the substrate connection wiring. Concave portions are formed in the corners connected to the side surface portions, the end portions of the substrate connection wiring are arranged along the recess portions, and the end treatment material is filled in the recess portions, and the end portions of the substrate connection wiring are embedded in the end treatment material. Relay board. A recess is formed in at least one of a corner portion connected to the side surface portion from the upper surface of the relay board body near the middle of the substrate connection wiring and a corner portion connected to the side surface portion from the lower surface of the relay board body near the middle of the board connection wiring. The relay board according to claim 1, wherein the board connection wiring is formed along the recess, the corner processing material is filled in the recess, and the corner of the substrate connection wiring is embedded in the corner processing material. A relay board body interposed between the first circuit board and the second circuit board;
Board connection wiring formed corresponding to the electrical connection location from the surface on the first circuit board side of the relay board body to the surface on the second circuit board side, and the relay board body The corrugated curved surface has at least one of the corner portion continuous from the surface on the first circuit board side to the side surface portion and the corner portion continuous from the surface on the second circuit board side to the side surface portion. The relay substrate is formed on a slope having a curved surface, and an end portion and a corner portion of the substrate connection wiring are attached along the slope having the corrugated curved surface. The relay board according to any one of claims 1 to 3 is interposed between the first circuit board and the second circuit board, and the first and second circuit boards are three-dimensionally connected. Three-dimensional wiring structure. A first step of forming a three-dimensional molded body by injection-molding a first resin using a first mold in a substrate shape to connect and relay a circuit board in the vertical direction;
A second step of injection-molding a fourth resin by using a second mold in addition to the portion for forming the substrate connection wiring for electrically connecting the connection land electrode to the side surface of the connection land electrode;
A third step of forming a plating catalyst on the substrate connection wiring portion that electrically connects the connection land electrode portions on the upper and lower surfaces of the three-dimensional molded body and the connection land electrodes on the side surfaces;
A fourth step of removing and plating the fourth resin;
And a fifth step of covering the end portion of the connection land electrode with a third mold so as to embed the second resin by injection molding. And a step of forming the land electrode so that the end portion of the land electrode is embedded between the first insulating resin and the second resin formed in an S-shaped curve. The method for manufacturing a relay board according to claim 5. 6. The method of manufacturing a relay board according to claim 5, further comprising a step of secondary molding so that the wiring at the corner portion connected to the side surface portion from the land electrodes on the upper and lower surfaces of the relay board is embedded in the resin. .   The portable terminal device by which the electric circuit board was mounted by the three-dimensional wiring structure of Claim 4.

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