JP2014067794A - Mounting structure and method of manufacturing mounting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve high-density mounting of electronic components to reduce the size and thickness of the whole mounting structure.SOLUTION: A main substrate 11 and a plurality of sub-substrates 12 which are placed on the main substrate 11 and electrically connected to the main substrate 11 are provided. The sub-substrate 12 has a pad 13 on its end. A main surface 12a of the sub-substrate 12 is arranged so as to intersect a main surface 11a of the main substrate 11. The pad 13 is bonded to the main surface 11a of the main substrate 11. A plurality of the sub-substrates 12 surround a part of the main surface 11a of the main substrate 11 and are arranged so as to form a space 15 inside. The main surface 12a of the plurality of the sub-substrates 12 is tilted toward the inside. An electronic component 16 is mounted on at least one of the main surface 12a inside the sub-substrate 12 and the main surface 11a of the main substrate 11 in the space 15.

Description

  The present invention relates to a mounting structure in which a sub-board is provided on a main board and a manufacturing method thereof.

  There is a demand for downsizing and thinning of electronic devices, especially portable devices. To reduce the size of the main surface of the main board, electronic components mounted on the main board are downsized and mounted on the main board. By reducing the gap between electronic components, downsizing and thinning have been promoted.

  Also known is a structure for mounting more electronic components by providing a connector on the main board and inserting the mounting board on which the electronic components are mounted through the connector so as to stand vertically with respect to the main board. Yes.

  However, in this structure, since the connector provided on the main board is thicker than the thickness of the main board, the main board is increased in size in the thickness direction, and the connector is disposed on the main surface of the main board. There is a disadvantage that the mounting area on the main board is reduced.

  Furthermore, as a mounting structure related to the present invention, in order to increase the mounting density of electronic components, a sub-board on which electronic components are mounted on the main surface of the main board is soldered without using a connector. The structure connected by attaching is disclosed (for example, refer patent document 1).

Japanese Utility Model Publication No. 60-109358

  However, in the configuration described in Patent Document 1 described above, the height of the sub-board that extends in a direction orthogonal to the main surface of the main board is bulky, and the sub-board increases in size in the thickness direction of the main board. There is a problem that invites.

  As a countermeasure, when the height of the sub-board extending in the direction orthogonal to the main surface of the main board is lowered, the mounting area of the sub-board is reduced, so it is difficult to sufficiently realize a high mounting density. It is.

  Then, an object of this invention is to provide the manufacturing method of the mounting structure which can solve the subject of the said related technique, and a mounting structure. An example of the object of the present invention is to provide a mounting structure and a manufacturing method of the mounting structure that can increase the mounting density of electronic components and reduce the size and thickness of the mounting structure.

  In order to achieve the above-described object, a mounting structure according to the present invention includes a main board and a plurality of sub-boards provided on the main board and electrically connected to the main board. A terminal is provided at the end, the main surface of the sub-board is arranged so as to intersect the main surface of the main substrate, and the terminal is bonded to the main surface of the main substrate. The plurality of sub-boards are arranged so as to surround a part of the main surface of the main board and form a space inside, and the main faces of the plurality of sub-boards are inclined inward. An electronic component is mounted on at least one of the main surface inside the sub-board and the main surface of the main board in the space.

  The method for manufacturing a mounting structure according to the present invention includes a main board and a plurality of sub boards provided on the main board and electrically connected to the main board, and the sub board is provided at an end portion. A method of manufacturing a mounting structure having a terminal, the main surface of the sub-board intersecting with the main surface of the main substrate, and the terminal bonded to the main surface of the main substrate, There is a step of arranging the main surfaces of the plurality of sub-boards to be inclined inward so as to surround a part of the main surface of the main board and to form a space inside.

  According to the present invention, the plurality of sub-boards are arranged so as to surround a part of the main surface of the main board and form a space on the inner side, and are inclined toward the inner side. It is possible to reduce the height of the sub-board occupying the direction orthogonal to the main surface of the substrate, increase the mounting density of the electronic components, and reduce the size and thickness of the mounting structure.

It is a perspective view which shows the mounting structure of 1st Embodiment. It is sectional drawing which shows the mounting structure of 1st Embodiment. It is a perspective view which shows the state which assembled the sub-board | substrate in the mounting structure of 1st Embodiment. It is a top view for demonstrating the sub-board | substrate in the mounting structure of 1st Embodiment. It is sectional drawing for demonstrating the junction location of the main board | substrate and subboard | substrate in the mounting structure of 1st Embodiment. It is sectional drawing for demonstrating the junction location of the main board | substrate and subboard | substrate in the mounting structure of 1st Embodiment. It is a perspective view which shows typically the mounting structure of 2nd Embodiment. It is a top view which shows typically the mounting structure of 2nd Embodiment. It is a perspective view which shows typically the mounting structure of 3rd Embodiment. It is a top view which shows typically the mounting structure of 3rd Embodiment. It is a perspective view which shows the other structural example of the mounting structure of embodiment. It is a perspective view which shows the other structural example of the mounting structure of embodiment. It is a perspective view for demonstrating the other structural example of the mounting structure of embodiment.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a perspective view of the mounting structure according to the first embodiment. FIG. 2 is a sectional view of the mounting structure according to the first embodiment. 2 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a perspective view showing a state in which the sub-board is assembled in the mounting structure according to the first embodiment.

  As shown in FIG. 1, the mounting structure 1 of the first embodiment includes a main board 11 and a plurality of sub-boards 12 provided on the main board 11 and electrically connected to the main board 11. I have. The sub-board 12 has a pad 13 as a terminal at the end, the main surface 12 a of the sub-board 12 is disposed orthogonal to the main surface 11 a of the main substrate 11, and the pad 13 is on the main surface 11 a of the main substrate 11. It is joined.

  As shown in FIG. 1 and FIG. 2, the plurality of sub-boards 12 are arranged so as to surround a part of the main surface 11 a of the main board 11 and form a space 15 on the inner side. Twelve major surfaces 12 a are inclined toward the inner space 15. Electronic components 16 are mounted on both the main surface 12 a inside the sub-board 12 and the main surface 11 a of the main substrate 11 in the space 15.

  In FIG. 4, the top view for demonstrating the subboard | substrate 12 in the mounting structure 1 of 1st Embodiment is shown. As shown in FIGS. 3 and 4, each of the four sub-boards 12 includes a rigid board 12r having a main surface 12a formed in a substantially trapezoidal shape, and is connected to each other via a flexible board 12f. It is configured. The rigid flexible substrate constituting the four sub-substrates 12 forms a space 15 inside the four sub-substrates 12 by bending the flexible substrate 12f so as to form a substantially quadrangular pyramid shape as a predetermined three-dimensional shape. It is formed in a cylindrical shape.

  Since the four sub-boards 12 are rigid flexible boards, the relative positioning work, the adjustment work of the inclination angle of the sub-board 12 with respect to the main board 11, and the work of fixing the ends of the sub-boards 12 are one. Since it becomes unnecessary except for the part, the assemblability is improved.

  An electronic component 16 is mounted in advance on the main surface 12 a inside each sub-board 12. Of course, the electronic component 16 may be mounted on the outer main surface 12a of each sub-board 12 as necessary. In the embodiment, the rigid flexible substrate constituting the four sub-substrates 12 is used. However, it is needless to say that only the sub-substrate composed of the rigid substrates may be used.

  FIG. 5 and FIG. 6 are cross-sectional views for explaining the joint location between the main board 11 and the sub board 12 in the mounting structure 1 of the first embodiment. As shown in FIGS. 5 and 6, the sub-board 12 is arranged such that the pads 13 provided at one end of the main surface 12 a are in contact with the pads 14 on the main surface 11 a of the main substrate 11.

  Subsequently, a connection paste 17 such as a solder paste or a conductive paste is applied to a connection portion between the pad 13 of the sub-board 12 and the terminal of the main board 11 using a dispenser. Then, the connection paste 17 applied to the connection portion between the sub-substrate 12 and the main substrate 11 is heated and melted, and the connection paste 17 is solidified, so that the connection paste 17 is solidified at a predetermined position on the main surface 11 a of the main substrate 11. Connected.

  The inclination angle formed between the main surface 12a inside the sub-board 12 and the main surface 11a of the main board 11 in the space 15 is set to be less than 90 degrees and 30 degrees or more. When the inclination angle formed by the main surface inside the sub-board 12 with respect to the main board 11 is less than 30 degrees, the electronic component 16 mounted on the main surface 11a of the main board 11, the sub-board 12 and the sub-board 12 is not preferable because the electronic component 16 mounted on the connector 12 may come into contact with the electronic component 16.

  Moreover, although not shown in figure, the electronic component 16 is mounted on the main surface 11a of the main board 11 in a region on the outer peripheral side of the sub board 12 assembled in a cylindrical shape as necessary. In the technology related to the mounting structure of the present invention, for example, chip components as electronic components 16 such as a decoupling capacitor and a damping resistor are mounted in a wide range around an LSI (Large Scale Integrated Circuit). According to the embodiment, these chip components are mounted on a plurality of sub-boards 12, and the sub-board 12 is arranged in a narrow range around the LSI, whereby the electronic component 16 occupies the main surface 11a of the main board 11. The area can be reduced. As a result, the mounting density of the electronic components 16 is increased, and the plurality of sub-boards 12 are inclined in a compact manner, whereby the entire mounting structure 1 is reduced in size and thickness.

  A manufacturing method for manufacturing the mounting structure 1 configured as described above will be described. On the plurality of sub-boards 12 used in the mounting structure 1, electronic components 16 are mounted in advance on the inner main surface 12 a located in the space 15. Further, the electronic component 16 is mounted on the main surface 11 a of the main board 11 in an inner region surrounded by the plurality of sub-boards 12. If necessary, the electronic component 16 may be mounted on only one of the main surface 11a of the main board 11 and the main surface 12a of the sub-board 12 in the space 15.

  Next, the plurality of sub-boards 12 on which the electronic components 16 are mounted are bent and assembled into a cylindrical shape as shown in FIG. The sub-boards 12 assembled in a cylindrical shape are arranged at predetermined positions on the main surface 11 a of the main board 11 so that the pads 13 of each sub-board 12 abut on the terminals of the main board 11.

  On the main surface 11a of the main substrate 11, the sub substrate 12 bent in a cylindrical shape is disposed, and the main substrate 11 and the pads 13 of each sub substrate 12 are electrically connected using a connection paste. As described above, by assembling the plurality of sub-substrates 12 assembled in a cylindrical shape on the main substrate 11, the work of assembling the plurality of sub-substrates 12 into a predetermined form is simplified, and the workability of the assembly process is improved. Is improved.

  As described above, according to the mounting structure 1 of the embodiment, the plurality of sub-boards 12 are disposed so as to surround a part of the main surface 11a of the main board 11 and form the space 15 inside. In both cases, the plurality of sub-boards 12 are inclined inward, whereby the height of the sub-board 12 occupying in the direction orthogonal to the main surface 11a of the main board 11 can be reduced. In addition, the electronic component 16 is mounted on the main substrate 11 and the sub substrate 12 in the space 15 formed by the plurality of sub substrates 12, thereby realizing high-density mounting of the electronic components 16. As a result, the mounting density of the electronic components 16 can be increased, and the entire mounting structure 1 can be reduced in size and thickness.

  Next, a mounting structure according to another embodiment will be described. Although the mounting structure 1 of the first embodiment is configured using four sub-boards 12, the present invention does not limit the number or shape of the sub-boards. In other embodiments, differences from the first embodiment will be described, and the same reference numerals as those in the first embodiment are used for the same components as those of the mounting structure of the first embodiment. The description is omitted.

(Second Embodiment)
FIG. 7 is a perspective view of the mounting structure according to the second embodiment. FIG. 8 is a plan view of the mounting structure according to the second embodiment.

  As shown in FIGS. 7 and 8, the mounting structure 2 of the second embodiment is configured by combining two sub-boards 22. The sub-board 22 is configured by a flexible board having a main surface 22a formed in a trapezoidal shape, and is assembled by being bent into an arc shape.

  Also in the present embodiment, as in the first embodiment, the plurality of sub-boards 22 are arranged so as to surround a part of the main surface 11a of the main board 11 so as to form a space on the inner side. It is inclined toward. The two sub-boards 22 constituting the mounting structure 2 are arranged on the main board 11 in a substantially truncated cone shape having an upper end opened.

  Also in the second embodiment, as in the first embodiment, the mounting density of the electronic components 16 can be increased, and the entire mounting structure 2 can be reduced in size and thickness.

(Third embodiment)
FIG. 9 is a perspective view of the mounting structure according to the third embodiment. FIG. 10 is a plan view of the mounting structure according to the third embodiment.

  As shown in FIGS. 9 and 10, the mounting structure 3 according to the third embodiment is configured by combining three sub-boards 32. The three sub-boards 32 are constituted by a rigid flexible board in which a rigid board having a main surface 32a formed in a trapezoidal shape is connected via a flexible board.

  Also in the present embodiment, as in the first embodiment, the plurality of sub-substrates 32 surround a part of the main surface 11a of the main substrate 11 and are arranged so as to form a space 15 inside. It is inclined toward the inner space 15. The three sub-boards 32 constituting the mounting structure 3 are arranged on the main board 11 in a substantially triangular frustum shape whose upper end is open.

  In the third embodiment, as in the first embodiment, the mounting density of the electronic components 16 can be increased, and the entire mounting structure 3 can be reduced in size and thickness.

  Finally, another configuration example of the mounting structure according to the embodiment will be described with reference to FIGS. As shown in FIG. 11, the mounting structure 4 of this embodiment is provided with a top plate 19 made of a conductive material so as to close the openings 18 of the four sub-boards 12 assembled in a cylindrical shape.

  A so-called solid pattern as a conductive layer is formed on the inner main surface or the outer main surface of the space 18 on the sub-board 12, and the solid pattern and the top plate 19 are electrically connected.

  The mounting structure 4 according to the present embodiment includes the top plate 19 that is electrically connected to the sub-board 12, thereby improving the electromagnetic shielding characteristics of the electronic component 16 mounted in the space 15. Moreover, the top plate 19 may be connected to any of the four sub-boards 12 so as to be bendable, and the assemblability can be improved.

  As shown in FIG. 12, in the mounting structure 5, another sub-board 52 is electrically connected to at least one of the four sub-boards 12 in a space 15 formed by the four sub-boards 12. Arranged. The main surface 52a of the other sub-board 52 is arranged orthogonal to the main surface 11a of the main board 11, and the electronic component 16 is mounted thereon.

  According to the mounting structure 5, the other sub-board 52 is arranged in the space 15 formed by the sub-board 12, thereby increasing the mounting area inside the space 15 and further increasing the mounting density, and the mounting structure. The mechanical strength of the body 5 can be increased. Of course, the mounting structure 5 may include the top plate 19 described above.

  As shown in FIG. 13, when manufacturing the mounting structure 5 using another sub-board 52, the other sub-board 52 and the sub-board 12 connected to the other sub-board 52 are placed on the main board 11. Each has a step of bonding in advance, and a step of assembling the mounting structure 5 by bonding the remaining sub-board 12 onto the main board 11 after this step.

  The mounting structure according to the present invention is preferably applied to a portable device that is required to be reduced in size and thickness.

DESCRIPTION OF SYMBOLS 1 Mounting structure 11 Main board 11a Main surface 12 Sub-board 12a Main surface 13 Pad 15 Space 16 Electronic component

Claims (7)

A main board; and a plurality of sub boards provided on the main board and electrically connected to the main board, the sub board having a terminal at an end thereof, and a main surface of the sub board Is disposed so as to intersect the main surface of the main substrate, and the terminal is bonded to the main surface of the main substrate,
The plurality of sub-substrates are disposed so as to surround a part of the main surface of the main substrate and form a space inside, and the main surfaces of the plurality of sub-substrates are inclined toward the inner side. ,
An electronic component is mounted on at least one of the inner main surface of the sub-board and the main surface of the main board in the space. The opening of the other end opposite to the end of the plurality of sub-substrates is closed by a top plate made of a conductive material,
The conductive layer is formed on the inner main surface or the outer main surface of the space, and the conductive layer and the top plate are electrically connected to the sub-board. 2. The mounting structure according to 1. The plurality of sub-boards are connected to each other through a flexible board,
The mounting structure according to claim 2, wherein the top plate is foldably connected to the sub-board.   The mounting structure according to any one of claims 1 to 3, further comprising another sub-board disposed in the space and electrically joined to the plurality of sub-boards.   The mounting structure according to claim 1, wherein an inclination angle formed by the inner main surface of the sub-board with respect to the main surface of the main board is 30 degrees or more. A main board; and a plurality of sub boards provided on the main board and electrically connected to the main board, the sub board having a terminal at an end thereof, and a main surface of the sub board Is arranged to intersect with the main surface of the main substrate, and the terminal is bonded to the main surface of the main substrate,
The plurality of sub-boards are arranged with the main surfaces of the plurality of sub-boards inclined toward the inside so as to surround a part of the main surface of the main board and form a space inside. The manufacturing method of the mounting structure which has the process to do.   The method for manufacturing a mounting structure according to claim 6, further comprising a step of mounting an electronic component on at least one of the inner main surface of the sub-board and the main surface of the main board in the space. .

Images