JP2008311267A - Circuit module manufacturing method and circuit module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit module manufacturing method for reducing an occupied area of a spacer as much as possible to ensure a mounting area of electronic components, and provide a small-sized circuit module having a high component mounting density by using the manufacturing method. <P>SOLUTION: The manufacturing method includes the steps of: preparing an assembled substrate 2a of a first circuit substrate 2; mounting spacers 4 on the assembled substrate 2a of the first circuit substrate 2 at a cutting scheduled line CL; laminating a second circuit substrate 3 on the spacer 4; filling a sealing resin 5 in a space between the assembled substrate 2a of the first circuit substrate 2 and the second circuit substrate 3; and cutting and dividing the assembled substrate 2a of the first circuit substrate 2 for every spacer 4 along the cutting scheduled line CL. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a circuit module by three-dimensional mounting and a circuit module obtained by the manufacturing method.

  In recent years, communication devices such as mobile phones and various electronic devices have been reduced in size and functionality. For this reason, there is an increasing demand for miniaturization of circuit modules constituting these devices, and with the increase in functionality of devices, the density of electronic components mounted on the circuit modules is increasing.

In order to meet such demands for high-density mounting accompanying downsizing and further enhancement of functionality, three-dimensional mounting in which a plurality of circuit boards on which electronic components are mounted has been proposed. As an example of three-dimensional mounting, there is a circuit device disclosed in Japanese Patent Laid-Open No. 2001-144244. In this circuit device, a plurality of mounting boards are connected in the vertical direction using bumps as spacers, and a space formed by the bumps or the entire space including the spaces is covered with an insulating resin. The circuit module formed by such three-dimensional mounting can realize high-density mounting, and further can achieve downsizing.

JP 2001-144244 A

However, in the method of stacking the mounting substrates using the bumps as spacers as described above, the area occupied by the bumps has become a problem as the circuit module becomes smaller. In the case of three-dimensional mounting, electronic parts are also mounted in the space between the mounting boards, so that the space needs to be higher than the height of the component to be mounted. Therefore, for example, when a solder ball is used as the bump, an area corresponding to a diameter approximately equal to the height of the bump is required. Therefore, as a method for reducing the area occupied by the bumps, a method using a bump having a relatively large aspect ratio such as a stud bump or a metal post can be considered. However, as the bump mounting area becomes smaller, it becomes more difficult to mount the bump and the support of the second circuit board becomes unstable, so there is a limit to increasing the bump aspect ratio. .

In recent years, in order to improve productivity and reduce manufacturing costs, a large number of circuit modules are formed on a single substrate, and then cut and divided by a dicing saw or wire saw in a later process to manufacture individual circuit modules. That is, a large number of pieces are taken. In such a method, a space for cutting is required, which further presses down the mounting area of the electronic component. Therefore, miniaturization and high-density mounting are becoming difficult.

Therefore, the present invention proposes a method of manufacturing a circuit module that can secure the mounting area of an electronic component by minimizing the area occupied by the spacer when a large number of three-dimensionally mounted circuit modules are obtained. In addition, a small circuit module having a high component mounting density that can be manufactured by using this manufacturing method is proposed.

  In the present invention, as a first solution, a first circuit board having an electronic component mounted on one surface and a second circuit board having an electronic component mounted on one surface are stacked via a spacer. In the method of manufacturing a circuit module, the step of preparing a collective board of the first circuit board, the step of mounting the spacer on a part of the cutting line of the collective board of the first circuit board, Mounting the second circuit board on a spacer, sealing a space between the assembly board of the first circuit board and the second circuit board with a curable resin, and Proposing a method of manufacturing a circuit module comprising: a step of cutting and dividing the aggregate substrate of the first circuit boards together with the spacers along the planned cutting line.

In the first solution, when the collective substrate is cut and divided, the spacer is divided at the same time. Therefore, the aspect ratio of the spacer after the division in the step of laminating the second circuit board on the first circuit board is increased (the aspect ratio is doubled when the spacer is divided in half). ). Therefore, by using a spacer having a relatively small aspect ratio in the laminating step, the mounting of the spacer on the first circuit board can be simplified and the support of the second circuit board can be stabilized. Further, after the division, the spacer aspect ratio can be increased to reduce the area occupied by the spacer on the circuit board.

Since the circuit module obtained by such a manufacturing method has a small occupied area of the spacer, the mounting area of the electronic component is increased, and the circuit module is small and has a high component mounting density.

Further, in such a circuit module, since the spacer is exposed on the side surface, the spacer can be used as a side terminal electrode by forming the spacer with a conductor such as metal. Therefore, in the present invention, as a second solution means, in addition to the first solution means, in the step of mounting the spacer on the first circuit board, the cutting line of the collective board of the first circuit board A method of manufacturing a circuit module is proposed in which a via is formed so as to straddle the substrate and the spacer formed of a conductor is mounted on the via.

According to the second solution, since the via conductor and the conductive spacer are electrically connected, soldering to the spacer is possible with the assistance of the via conductor. Therefore, the spacer can be used as a side terminal electrode.

  According to the present invention, the area occupied by the spacer can be reduced as much as possible, so that the mounting area of the electronic component in the circuit module can be increased. Further, by using this manufacturing method, a small circuit module having a high component mounting density can be obtained.

  A first embodiment according to a circuit module of the present invention will be described with reference to FIGS. In the following drawings, wiring on the circuit board is omitted for convenience. In the circuit module 1 shown in FIGS. 1 and 2, a second circuit board 3 is laminated on a first circuit board 2 via a spacer 4. The space between the substrate 2 and the second circuit board 3 and the second circuit board 3 are covered and filled with a sealing resin 5.

  This circuit module 1 is one of those obtained by cutting and dividing from a collective substrate in which a number of similar circuit modules are arranged in a lattice pattern. Therefore, the four side surfaces of the circuit module 1 are cut surfaces. The spacer 4 is exposed at a part of this side surface. Since the spacers 4 are arranged on the planned cutting line of the collective substrate, they are cut at the same time during the cutting division. Therefore, the cut surface of the spacer 4 exists on the same plane as the cut surface of the circuit module 1.

  The first circuit board 2 is provided in the form of a collective board, and is divided into individual circuit boards when the circuit module 1 is cut out from the collective board. Therefore, the cut surface of the first circuit board 2 exists on the same plane as the cut surface of the circuit module 1, and also exists on the same plane as the cut surface of the spacer 4. The first circuit board 2 is a single-layer board in FIGS. 1 and 2, but a multi-layer board may be used, or a multi-layer board incorporating passive electronic components such as a capacitor and a coil conductor may be used. Further, the first circuit board 2 has electronic components mounted on one side in FIGS. 1 and 2, but it may also have electronic components mounted on both sides. As the material for the substrate, a resin substrate such as glass-epoxy resin, paper-phenol, polyimide resin, or a ceramic substrate such as alumina or titanium oxide is used.

  The second circuit board 3 is laminated on the first circuit board 2 via the spacer 4. When the second circuit board 3 is stacked, the second circuit board 3 may be supplied in the form of a collective board, or may be supplied after being divided into individual circuit boards in advance. Further, the second circuit board 3 has a size smaller than that of the first circuit board 2 in FIGS. 1 and 2, but may be a board having the same size. Further, the second circuit board 3 is exposed at the side surface of the board in FIGS. 1 and 2, but may be entirely covered with a sealing resin. Similarly to the first circuit board 2, the second circuit board 3 may be an electronic component mounted on one side or an electronic component mounted on both sides, and the same substrate material is used. . However, the material of the first circuit board 2 and the material of the second circuit board 3 may be different or the same.

  The spacer 4 forms a space between the first circuit board 2 and the second circuit board 3, and the height dimension thereof is mounted on the first circuit board 2 and the second circuit board 3. It is set as appropriate depending on the height of the electronic component. The spacers 4 are arranged on the planned cutting line of the collective substrate, and are divided into two at the time of cutting and dividing. That is, by sharing the spacer 4 between two adjacent individual circuit modules, the occupation area of the spacer 4 per circuit module can be reduced to half or less. Here, “to occupy less than half the area occupied by the spacer 4” means that when the spacer 4 is cut by using a relatively thick dicing blade when the aggregate substrate is cut and divided, the remaining spacer 4 This means that the occupied area is smaller than half of the occupied area of the original spacer 4 by the amount of cutting waste. Since the spacer 4 is cut and divided simultaneously with the circuit board, the same material as the first circuit board 2 and the second circuit board 3 can be used. Moreover, when using resin as the material of the spacer 4, various resin other than the same material as a circuit board can be utilized suitably. When a conductive metal such as Cu or Ni is used as the material of the spacer 4, it can be used as a connector for electrically connecting the wiring of the first circuit board 2 and the wiring of the second circuit board 3. it can. One or more spacers 4 may be provided for each individual circuit module, and the number thereof can be adjusted as appropriate. Moreover, when providing the spacer 4 with two or more, you may insert suitably what differs in a material.

  The sealing resin 5 is formed using an insulating curable resin such as a thermosetting resin, an ultraviolet effect resin, or a photocurable resin. Specific examples include epoxy resins and silicone resins. The sealing resin 5 may cover the entire circuit module 1 or a part of the circuit module 1, for example, fills only the space between the first circuit board 2 and the second circuit board 3. You may let them. The sealing resin 5 may be coated and filled before dividing the aggregate substrate, or may be coated and filled after dividing.

  Such a circuit module 1 is formed as follows. In addition, the manufacturing method of the circuit module of this invention is not limited to the following method, In the range of invention, it can change suitably.

First, as shown in FIG. 3, a first circuit board aggregate board 2a is prepared. As shown in FIG. 3A, the first circuit board collective board 2a has a plurality of circuit boards having the same wiring pattern and the same component arrangement arranged in a lattice pattern, and is divided by cutting lines CL. By doing so, the individual first circuit board 2 is obtained. The arrangement of the first circuit board collective boards 2a is such that the individual boards adjacent in the longitudinal direction are rotated by 180 degrees, and the individual boards adjacent in the width direction are arranged in the same direction. Yes. Further, the aggregate substrate 2a of the first circuit board may be provided with a groove or a perforation for facilitating cutting and dividing at a position corresponding to the planned cutting line CL.

  Next, as shown in FIG. 4A, the spacer 4 is mounted on the planned cutting line CL of the collective substrate 2a of the first circuit board. The spacer 4 is arranged to be in a line-symmetrical position with respect to the center line when the CC line in FIG. 4A is the center line of the individual substrate. When the spacer 4 is made of resin or ceramics, the space between the first circuit board 2 and the second circuit board 3 is simply formed, so the arrangement of the spacer 4 is not limited. 4 is used as a bump for electrically connecting the first circuit board 2 and the second circuit board 3, since the connection position is determined, it is arranged so as to be in a line symmetrical position with respect to the center line. To do. In this way, as shown in FIG. 4B, the spacers 4 are arranged so as to be divided by the planned cutting line CL.

  As a method of joining the spacer 4 to the collective substrate 2a of the first circuit board, when the material is resin or ceramic, bonding by an adhesive is exemplified, and when the material is metal, in addition to joining by an adhesive Various methods used for bonding metal bumps, such as soldering and ultrasonic bonding, can be used. In this case, a land is preferably formed at a position where the spacer 4 is mounted. The shape of the spacer 4 may be any shape that can stably support the substrate, such as a columnar shape or a prismatic shape.

  Next, as shown in FIG. 5A, the second circuit board collective substrate 3 a is mounted on the spacer 4. In FIG. 5, since the dimension of the second circuit board 3 is smaller than the dimension of the first circuit board 2, the collective board 3 a of the second circuit board is parallel to the length direction of the first circuit board 2. It will be two in a row. The two sheets are arranged in a 180 degree rotation with respect to each other. As shown in FIG. 5 (b), the cut line of the collective board 3a of the second circuit board is mounted so as to match the cut line of the collective board 2a of the first circuit board. As a joining method, the method used for joining the aggregate substrate 2a of the first circuit board and the spacer 4 can be used.

  Next, as shown in FIG. 6, the sealing resin 5 covers and fills the assembly board 2 a of the first circuit board, the assembly board 3 a of the second circuit board, and the periphery of the spacer 4. Next, it is cut and divided using a dicing saw or a wire saw along the planned cutting line CL. In this way, individual circuit modules 1 are obtained. The sealing resin 5 may be coated / filled after the aggregate substrate is cut and divided, but cut in a state where the production efficiency and the lamination of the first circuit board 2 and the second circuit board 3 are stabilized. In order to perform the division, it is preferable to cover and fill the sealing resin 5 first.

  Next, a second embodiment according to the circuit module of the present invention will be described with reference to FIGS. In the circuit module 11 shown in FIGS. 7 and 8, a second circuit board 13 is laminated on a first circuit board 12 via a spacer 14, and the first circuit board 12 has a first circuit. The space between the substrate 12 and the second circuit board 13 and the second circuit board 13 are covered and filled with a sealing resin 15. The difference from the first embodiment is that the spacer 14 serves as a terminal electrode, and the spacer 14 is mounted on the via 16 formed in the first circuit board 12.

  The via 16 is formed to assist in using the spacer 14 as a side terminal electrode. When the via is not formed, the first circuit board 12 itself does not have good solder wettability, which prevents the solder from attaching to the spacer 14. As a result, the terminal electrode is not soldered. Here, when the spacer 14 is mounted on the via 16, the metal film of the via 16 improves the solder wettability, so that the solder wets the spacer 14. As a result, the terminal electrode is soldered. That is, since the via 16 helps the solder to be attached to the spacer 14, the spacer 14 can be used as a side terminal electrode.

  Such a circuit module 11 is formed as follows. First, as shown in FIG. 9, a first circuit board aggregate board 12a is prepared. The first circuit board collective board 12a is similar to the first circuit board collective board 2a of the first embodiment described above in that a plurality of circuit boards having the same wiring pattern and the same component arrangement are arranged in a grid pattern. Are listed. And the via | veer 16 is formed so that the cutting planned line CL of the position in which a side terminal electrode is formed may be straddled. The via 16 can be formed by a well-known via forming method, for example, a method of making a hole with a drill and filling the hole with electroless plating or a conductive paste. The vias 16 are arranged so as to be line-symmetric with respect to the center line in the length direction of the first circuit board 12.

  Next, as shown in FIG. 10, a spacer 14 made of a conductive metal is mounted on the via 16. For joining the spacer 14 and the via 16, various methods used for joining metal bumps, such as soldering and ultrasonic joining, can be used.

  Next, as shown in FIG. 11, a second circuit board aggregate board 13 a is mounted on the spacer 14. When the spacer 14 is used as a terminal electrode of the second circuit board 13, it is preferable that a land is provided on the second circuit board 13 at a position where the spacer 14 is joined to be electrically joined. . However, when it is not necessary to electrically connect, it is not necessary to form a land, and a bonding method can be applied as a bonding method. The subsequent steps are the same as in the first embodiment. Thus, the circuit module 14 using the spacer 14 as the side terminal electrode can be obtained.

  The circuit modules 1 and 11 according to the first embodiment and the second embodiment can minimize the area occupied by the spacer and maximize the mounting area of the electronic component. As a result, it is possible to realize a three-dimensional mounting that provides a small and highly functional circuit module.

1 is a perspective view schematically showing a first embodiment of a circuit module of the present invention. It is the schematic cross section which looked at the circuit module of FIG. 1 from the AA line. It is a figure which shows the step in 1st embodiment of the circuit module of this invention, (a) is a fragmentary perspective view which shows typically the aggregate substrate 2a of a 1st circuit board. (B) is the typical fragmentary sectional view which looked at the aggregate substrate 2a of (a) from the BB line. It is a figure which shows the step in 1st embodiment of the circuit module of this invention, (a) is a fragmentary perspective view which shows typically a mode that the spacer 4 was mounted in the aggregate substrate 2a of a 1st circuit board. (B) is the typical fragmentary sectional view which looked at the aggregate substrate 2a of (a) from CC line. It is a figure which shows the step in 1st embodiment of the circuit module of this invention, (a) mounts the assembly board 3a of the 2nd circuit board on the assembly board 2a of the 1st circuit board via the spacer 4. It is a fragmentary perspective view which shows the mode which performed. (B) is the typical fragmentary sectional view which looked at the aggregate substrate 2a of (a) from the DD line. It is a figure which shows the step in 1st embodiment of the circuit module of this invention, and is a fragmentary sectional view which shows typically a mode that the aggregate substrate was coat | covered with sealing resin. It is a perspective view showing typically a 2nd embodiment of a circuit module of the present invention. It is the schematic cross section which looked at the circuit module of FIG. 7 from the EE line. It is a figure which shows the step in 2nd embodiment of the circuit module of this invention, and is a fragmentary perspective view which shows typically the aggregate substrate 12a of a 1st circuit board. It is a figure which shows the step in 2nd embodiment of the circuit module of this invention, and is a fragmentary perspective view which shows typically a mode that the spacer 14 was mounted in the aggregate substrate 12a of the 1st circuit board. It is a figure which shows the step in 2nd embodiment of the circuit module of this invention, and shows a mode that the collective board 13a of the 2nd circuit board was mounted on the collective board 12a of the 1st circuit board via the spacer 14. FIG. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 11 Circuit module 2, 12 1st circuit board 2a, 12a 1st circuit board aggregate board 3, 13 2nd circuit board 3a, 13a 2nd circuit board aggregate board 4, 14 Spacer 5, 15 Sealing resin 16 Via

Claims (4)

In a method for manufacturing a circuit module, in which a first circuit board having an electronic component mounted on one surface and a second circuit board having an electronic component mounted on one surface are stacked via a spacer,
Preparing a collective substrate of the first circuit board;
Mounting the spacer on a portion of the first circuit board on the cutting line of the assembly board; and
Laminating the second circuit board on the spacer;
Sealing the space between the assembly board of the first circuit board and the second circuit board with a curable resin;
Cutting and dividing the aggregate substrate of the first circuit board together with the spacer along the planned cutting line;
A method for manufacturing a circuit module, comprising:   2. The via according to claim 1, wherein a via is formed so as to straddle a scheduled cutting line of the collective substrate of the first circuit board, and the spacer formed of a conductor is mounted on the via. Circuit module manufacturing method. A first circuit board with electronic components mounted on one side and a second circuit board with electronic components mounted on one side are stacked via a spacer and cut and divided into a substantially rectangular shape. In the formed circuit module,
The spacer is disposed near a side surface of the first circuit board, and the cut surface of the spacer and the cut surface of the first circuit board exist on the same plane. Circuit module. The circuit module according to claim 3, wherein the spacer is formed of a conductor and constitutes a side terminal electrode.

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