JP2011071421A - Circuit module and method of mounting circuit module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit module whose attitude angle to a mounting substrate of the circuit module can be controlled with high precision. <P>SOLUTION: The circuit module 1 includes a circuit board 10 having at least a first and second surface, an element chip 20 mounted on the first surface, and a projection electrode 30 formed on the second surface of the circuit board, the projection electrode 30 being connected to a wiring pattern 101 on the mounting substrate 100. The circuit module 1 includes: the circuit board; spacer members 50a, 50b having a first abutting surface which protrudes from the projection electrode toward the mounting substrate and abuts against the mounting substrate side so as to predefine an interval with the mounting substrate, and abutting against the mounting substrate and a second abutting surface provided opposite the first abutting surface; and a pressing member 60 pressing the spacer members 50a, 50b against the mounting substrate side. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a circuit module and a circuit module mounting method, and more particularly to mounting a circuit module on a mounting board (motherboard).

For example, as shown in FIG. 7, solder 130 is often used when an electronic component in which an element chip 120 such as a gyro sensor is mounted on a circuit board 110 is mounted on the mounting board 100. FIGS. 8A and 8B are diagrams showing a circuit module including the element chip 120 and the circuit board 110 for each component. 9A to 9C show a process of mounting the circuit board 110 on which the element chip 120 is mounted on the mounting board 100. FIG.
One of the conditions for exerting the function of the gyro sensor is that the sensor needs to be arranged so as to be perpendicular to the mounting substrate.
For this reason, a method is adopted in which the module and the substrate are arranged vertically by applying the solder to a uniform thickness or fixing the position until the solder is fixed after the solder mounting. This method is very difficult because it controls an unstable amount of solder application. Even if the control of the solder amount is realized, there are problems that the control lead time is extended for fixing the position, and the position fixing jig is exposed to a high temperature and the position accuracy is not stable.

  For example, a configuration has been proposed in which an electronic component is provided with an insulator portion that protrudes toward a mounting substrate such as a printed circuit board to secure an adhesive region by solder (Patent Document 1).

Japanese Patent Laid-Open No. 11-026910

  Even in the mounting structure of Patent Document 1, it is difficult to control the unstable amount of solder application, and the control lead time is extended to fix the position, or the position fixing jig is exposed to high temperatures and the position accuracy is increased. There was a problem that was not stable.

  As described above, conventionally, when solder mounting on a circuit module such as an electronic component, it has been extremely difficult to control the attitude angle of the circuit module with respect to the mounting substrate with high accuracy.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a circuit module capable of controlling the attitude angle of the circuit module with respect to the mounting substrate with high accuracy.

Therefore, the present invention includes a circuit board having at least first and second surfaces, an element chip mounted on the first surface, and a protruding electrode formed on the second surface of the circuit board. A circuit module configured such that the protruding electrode is connected to a wiring pattern on a mounting substrate, wherein the mounting is performed more than the protruding electrode so as to define an interval between the circuit substrate and the mounting substrate. A spacer member that protrudes toward the substrate and has a first contact surface that contacts the mounting substrate; and a second contact surface that is provided opposite to the first contact surface; A circuit module having a pressing member for pressing toward the substrate side is configured.
According to this configuration, since the spacer member is pressed using the pressing member, the protruding electrode can be efficiently fixed to the mounting substrate while maintaining the posture angle of the circuit module, and a highly accurate posture angle can be obtained. Implementation of a circuit module is realized. Here, the first and second surfaces may be in any positional relationship as long as they are other than the same surface.

The present invention includes the above circuit module, wherein the pressing member is a weight placed on the second contact surface.
According to this configuration, since the spacer member is pressed against the mounting board using the weight as the pressing member, the protruding electrode can be efficiently mounted on the mounting board.

The present invention includes the above circuit module, wherein the pressing member is insert-molded on the spacer member.
According to this configuration, the pressing member is insert-molded in the resin, so that the pressing member can be attached without mounting a separate weight during the mounting process.

Further, the present invention includes the above circuit module, wherein the spacer member is a support leg provided so as to protrude on both sides of the circuit board.
According to this configuration, more stable support is realized by using the support leg portions that protrude from both sides.

According to the present invention, in the circuit module, the second surface is smaller than the other surface, and the support leg protrudes on both sides of the circuit board, and is further orthogonal to the protruding direction. Including a stretched portion that is stretched.
According to this configuration, even when the circuit module is supported on a surface having a smaller area than the other surfaces, the posture angle can be stably controlled by the presence of the supporting leg portion.

The present invention also includes a circuit board having at least a first surface and a second surface, an element chip mounted on the first surface, and a protruding electrode formed on the second surface of the circuit board. The protruding electrode is configured to be connected to a wiring pattern on a mounting substrate, and protrudes toward the mounting substrate from the protruding electrode to define a distance between the circuit substrate and the mounting substrate. A circuit module is provided that includes a first contact surface that contacts the mounting substrate, a spacer member provided opposite to the first contact surface, and a pressing member that presses the spacer member toward the mounting substrate. A step of supplying solder onto a mounting substrate having a wiring pattern, and positioning the circuit module on the mounting substrate and pressing the pressing member to cure and shrink the solder. substrate Wherein providing a mounting method of a circuit module comprising a step of securing the circuit module to.
According to this configuration, the circuit module is positioned on the mounting substrate and soldered while being pressed by the pressing member, so that the management of the solder application amount and the management of the inclination of the substrate and the module at the time of mounting are insufficient. Even in this case, the angle between the circuit module and the mounting substrate can be maintained as intended.

  According to the present invention, when the circuit module is mounted on the mounting board, the angle between the mounting board and the circuit module is determined by positioning the circuit module on the mounting board and curing and shrinking the solder while pressing with the pressing member. It is possible to maintain a constant angle without severely managing the solder application balance and mounting angle.

The perspective view which shows the state which mounted the circuit module of Embodiment 1 of this invention on the mounting board | substrate. The perspective view which shows the mounting process on the mounting substrate of the circuit module of Embodiment 1 of this invention The perspective view which shows the state which mounted the circuit module of the modification of Embodiment 2 of this invention on the mounting board | substrate. The perspective view which shows the state which mounted the circuit module of Embodiment 2 of this invention on the mounting board | substrate. The perspective view which shows the state which mounted the circuit module of Embodiment 3 of this invention on the mounting board | substrate. The perspective view which shows the circuit module of Embodiment 3 of this invention. The perspective view which shows the state which mounted the circuit module of the prior art example on the mounting board. A perspective view showing a manufacturing process of a conventional circuit module The perspective view which shows the process of mounting the circuit module of a prior art example.

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

(Embodiment 1)
FIG. 1 is a perspective view showing a state in which the circuit module according to Embodiment 1 of the present invention is mounted on a mounting board, and FIGS. 2 and 3 are perspective views showing a process of mounting the circuit module on the mounting board.
As shown in FIGS. 1 and 2, the circuit module 1 according to the present embodiment includes a circuit board 10 on which an element chip 20 constituting a gyro sensor is mounted on a first surface 10A that is a main surface. A protruding electrode 30 is formed on the third surface 10C, which is a side surface that is perpendicular to the first surface 10A and the second surface 10B opposite to the first surface 10B, and has a smaller area. The spacer members 50a and 50b projecting from each other and the weight as the pressing member 60 that presses the spacer members 50a and 50b are provided. The circuit board 10 is brought into contact with a printed wiring board as the mounting board 100, and the protruding electrode 30 formed on the third surface 10C and the mounting board 100 are fixed to each other through the solder layer 40. Has been. Here, the circuit board 10 is a resinous three-dimensional board formed by injection molding. Then, it is bonded via a solder layer 40 onto a pad made of the wiring pattern 101 formed on the mounting substrate 100. Here, the wiring conductor layer connected to the pad on the mounting surface on the circuit board 10, the die pad (element mounting area) formed on the element chip mounting surface, and the wiring conductor layer (not shown) including the bonding pad are three-dimensionally molded. Thus, a base layer is formed by a sputtering method on a resin substrate on which a protrusion having a predetermined height is formed, and a plating layer is formed on the base layer. Here, the protruding electrode is composed of a plating layer formed on the protruding portion. The connection between the element chip 20 and the circuit board 10 may be flip chip bonding or wire bonding.

  Here, the protruding electrode 30 is fixed by the solder layer 40, but in the solder reflow process, the spacer members 50a and 50b are fixed in a pressed state by a weight as the pressing member 60. For this reason, a gap is not formed between the protruding electrode 30 and the mounting substrate 100 at the time of mounting, and the shrinkage at the time of hardening of the solder layer is promoted by the weight, so that the protruding electrode 30 and the mounting substrate 100 are spaced from each other. Without touching.

  In manufacturing, since the gyro sensor is mounted on the first surface 10A, the circuit board 10 is designed and manufactured so that the directionality of the first surface 10A is maintained.

  Here, when the wiring conductor layer is formed on the three-dimensional board constituting the circuit board 10, first, the lower surface made of a conductive thin film is formed on the entire surface of the circuit board 10 by performing electroless plating, CVD, sputtering, or the like. Form a stratum. Here, a copper thin film is formed by electroless copper plating or sputtering. Then, by irradiating the surface of the circuit board 10 with a laser beam, the underlying layer of the irradiated portion is patterned and selectively removed. Here, the laser beam is irradiated while moving on the surface of the circuit board 10 along the outline of the wiring conductor layer to be formed by scanning with a galvanometer mirror or the like, and a portion of the underlying layer that matches the pattern of the wiring conductor layer And the base layer in the boundary region between the portion not matching the pattern of the wiring conductor layer is removed. Therefore, the surface of the circuit board 10 is removed by laser beam irradiation only on the inner layer of the contour irradiated with the laser beam (underlying layer matching the pattern of the wiring conductor layer) and the portion along the contour of the underlying layer. The underlying layer (not shown) remains. However, when the interval between the adjacent wiring conductor layers is narrow, it is possible to remove not only the contour portion but also the entire underlying layer between the wiring conductor layers by laser beam irradiation as described above.

  Subsequently, a surface conductor layer is formed by thickening a plating layer such as copper on the underlying layer that matches the pattern of the wiring conductor layer by electroplating, and unnecessary underlying plating layers other than the underlying layer are removed by etching. Then, the circuit board 10 on which a desired circuit pattern is formed can be obtained.

  In this way, the circuit board 10 having the protruding electrode 30 and the wiring conductor layer on the surface is designed, the element chip 20 is mounted on the circuit board, and electrical connection is performed by wire bonding or flip chip bonding. Form.

  The spacer members 50a and 50b are also formed on the side facing the mounting substrate, that is, on the third surface 10C side by forming a wiring conductor layer in the bonding process using the solder layer 40. As a result, a good connection can be made, and a more stable connection can be achieved.

A method for mounting the circuit module thus formed on the mounting substrate 100 will be described.
First, as shown in FIG. 2A, a mounting board 100 made of a printed wiring board is prepared. Then, the solder layer 40 is formed on the mounting substrate 100 while controlling the supply amount with a dispenser. At this time, the wiring pattern 101 is also formed on the mounting substrate 100 in a region corresponding to the protruding electrode 40 on the circuit board.

  Then, as shown in FIG. 2B, the solder layer 40 and the third surface 10C of the circuit board 10 are brought close to contact with each other. At this time, the protruding electrode 30 and the wiring pattern 101 are not yet connected.

  Then, it is heated to the solder reflow temperature, the solder is solidified and contracted, and the distance between the circuit module and the mounting substrate is reduced, so that the protruding electrode 30 and the wiring pattern 101 on the substrate 100 are arranged as shown in FIG. Are electrically connected. At this time, electrical connection is made by pressing the solder layer 40 through the spacer members 50a and 50b.

  Thus, by maintaining the distance between the circuit module 1 and the mounting substrate 100 with high accuracy, the attitude angle with respect to the circuit module can be maintained with high accuracy.

  In addition, according to the above configuration, it is possible to maintain a highly accurate angle in mounting a sensor device such as a gyro sensor whose directionality is extremely important.

  In the above embodiment, an example in which a flat circuit board is used as a circuit board has been described. is there.

  As a modification of the above embodiment, the weight may be constituted by a solder layer 41 as shown in FIG.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. FIG. 4 is a perspective view showing a state where the circuit module 2 according to the second embodiment of the present invention is mounted on a mounting board.
In the above embodiment, the weight is used as the pressing member 60. However, in this embodiment, the weight is insert-molded as the pressing member 61 in the spacer members 50a and 50b, and is used as an embedded weight. It is characterized by maintaining the above.
Since other parts are formed in the same manner as in the first embodiment, the description is omitted here.

In this case as well, the angle between the three-dimensional circuit board constituting the circuit module and the mounting board can be maintained at a constant angle without severely managing the solder application balance, the mounting angle, and the like.
Note that the insert molding of the weight is realized by placing the weight in a mold and performing injection molding.

(Embodiment 3)
Next, a third embodiment of the present invention will be described. FIG. 5 is a perspective view showing a state where the circuit module 2 according to Embodiment 3 of the present invention is mounted on a mounting board.
In the above-described embodiment, a weight is used as the pressing member. However, in this embodiment, a jig such as a suction nozzle is used for pressing only when bonding without using a weight. Here, the spacer members 51a and 51b are characterized in that they occupy a small area only by slightly protruding from the mounting surface of the circuit board.
Since other parts are formed in the same manner as in the first embodiment, the description is omitted here.

  In this case as well, the angle between the three-dimensional circuit board constituting the circuit module and the mounting board can be maintained at a constant angle without strictly managing the solder application balance, the mounting angle, and the like.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described. FIG. 6 is a perspective view showing a circuit module according to Embodiment 4 of the present invention.
In the first and second embodiments, the circuit module having the third surface 10C of the circuit board as the mounting surface has been described. However, the circuit module 3 having two or more surfaces as the mounting surface will be described.
In the present embodiment, the spacer member 52 is provided not only on the third surface 10C but also on the second surface 10B orthogonal to the third surface 10C, and on the spacer member 52 from the weight according to the mounting surface. The pressing member 60 is put on.
Since the basic structure is the same as that of the first embodiment, description thereof is omitted.

In the present embodiment, at the time of mounting, the height of the solder layer 40 may be determined by the protruding electrode as the spacer member 52 to ensure the connection.
Thereby, the space | interval of a circuit module and a mounting board can be maintained with high precision.
Note that when two or more surfaces are used as mounting surfaces, it is necessary to maintain a very high accuracy. However, according to the present embodiment, the height of the solder layer 40 is formed high and the protruding electrode 30 is formed. Since the height of the solder layer may be adjusted by the height of the height, it is possible to maintain a highly accurate interval.

  In the above embodiment, the circuit module (sensor module) on which a sensor chip such as a gyro sensor is mounted has been described. However, the present invention is not limited to the sensor module, and is mounted on a module mounted on a portable terminal or the like or on a wall surface. The present invention can be applied to various circuit modules such as LED modules for LED lighting.

In the above embodiment, a resin solid substrate formed by injection molding is used as the circuit substrate. However, a ceramic substrate or a laminated substrate using a green sheet may be used. Here, for example, it is made of ceramic dielectric material LTCC (Low Temperature Co-fired Ceramics) that can be sintered at a low temperature of 1000 ° C. or lower, and is made of a low resistivity Ag on a green sheet having a thickness of 10 μm to 200 μm. A conductive paste such as Cu or Cu is printed to form a predetermined pattern, and a plurality of green sheets are used as an insulating layer, and are laminated together as appropriate, and sintered to provide an insulating layer (dielectric) Body layer). As these dielectric materials, for example, Al, Si, Sr as main components, Ti, Bi, Cu, Mn, Na, K as subcomponents, Al, Si, Sr as main components, Ca, Pb A material containing Na, K as a multicomponent, a material containing Al, Mg, Si, Gd, or a material containing Al, Si, Zr, Mg is applicable. Here, a material having a dielectric constant of about 5 to 15 is used. In addition to the ceramic dielectric material, it is also possible to use a resin multilayer substrate or a multilayer substrate made of a composite material obtained by mixing a resin and ceramic dielectric powder. Further, the ceramic substrate is made of HTCC (High Temperature Co-fired Ceramics) technology, the dielectric material is mainly Al ₂ O ₃ , and the transmission line is made of tungsten as an internal conductor layer. You may comprise as a metal conductor which can be sintered at high temperature, such as molybdenum.

  Moreover, it is applicable to other ceramics without being limited to the green sheet, and when a resin substrate such as glass epoxy resin, polyimide resin, polyester resin, polyethylene terephthalate resin is used, a laminated substrate using a prepreg It is also applicable to.

Although the case where the element chip is mounted on the circuit board has been described in the above embodiment, an electronic component package may be used instead of the element chip.
Although the adhesive member is solder here, it is needless to say that the adhesive member is not limited to solder but can be applied to a conductive adhesive such as silver paste or an insulating adhesive.

1, 2, 3 Circuit module 10 Circuit board 10A First surface 10B Second surface 10C Third surface 20 Element chip 30 Protruding electrode 40 Solder layer 41 Solder layer (for weight)
50a, 50b, 52 Spacer member 60 Pressing member 61 Pressing member 100 Mounting board (printed wiring board)
101 Wiring pattern (pad)
110 Circuit board 120 Element chip 130 Solder

Claims (6)

A circuit board having at least first and second surfaces;
An element chip mounted on the first surface;
A protruding electrode formed on the second surface of the circuit board,
A circuit module configured such that the protruding electrode is connected to a wiring pattern on a mounting substrate,
A first contact surface that protrudes closer to the mounting substrate than the protruding electrode and contacts the mounting substrate, and a second contact surface that faces the mounting substrate, in order to define a distance between the circuit board and the mounting substrate. A spacer member having
A circuit module including a pressing member that presses the spacer member toward the mounting substrate. The circuit module according to claim 1,
A circuit module, wherein the pressing member is a weight placed on the second contact surface. The circuit module according to claim 2, wherein
A circuit module in which the pressing member is insert-molded in the spacer member. The circuit module according to any one of claims 1 to 3,
The circuit module, wherein the spacer member is a support leg provided so as to protrude from both sides of the circuit board. The circuit module according to claim 4,
The second surface is smaller than the other surfaces;
The circuit module having an extending portion in which the support leg protrudes on both sides of the circuit board and further extends in a direction orthogonal to the protruding direction. A circuit board having at least first and second surfaces;
An element chip mounted on the first surface;
A protruding electrode formed on the second surface of the circuit board,
The protruding electrode is configured to be connected to a wiring pattern on a mounting substrate,
In order to define the distance between the circuit board and the mounting board, the first contact surface protrudes from the protruding electrode toward the mounting board and contacts the mounting board, and is opposed to the first contact surface. A spacer member having a second contact surface provided as
Preparing a circuit module including a pressing member that presses the spacer member toward the mounting substrate;
Supplying solder onto a mounting substrate having a wiring pattern;
A method of mounting a circuit module, comprising: positioning the circuit module on the mounting board and fixing the circuit module on the mounting board by curing and shrinking solder while pressing the pressing module with the pressing member.

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