JP7354513B2 - Electronic circuit device and its manufacturing method - Google Patents

Description

The present invention relates to an electronic circuit device in which electronic components are mounted on a mounting board and a method for manufacturing the same, and more particularly to an electronic circuit device in which electronic components that are required to be mounted in an airtight manner are mounted and a method for manufacturing the same.

There is a strong demand for higher functionality and smaller size in mobile devices such as smartphones and tablet terminals, and wearable devices such as wristwatch-type pedometers, and the electronic circuit devices installed in these devices are required to be smaller.

In order to downsize electronic circuit devices, it is preferable to mount electronic components on a mounting board with high density. Various high-density-packed electronic circuit devices have been proposed (for example, Patent Document 1).

On the other hand, it is known that some electronic components mounted on a mounting board need to be mounted in an airtight state because their characteristics deteriorate due to moisture in the atmosphere. For example, all-solid-state batteries employ a method of maintaining an airtight state by glass sealing. (Patent Document 2).

Japanese Patent Application Publication No. 2002-76561 JP 2018-170297 Publication

With conventional high-density mounting structures, electronic components cannot be mounted in an airtight manner. Therefore, it was necessary to add a complicated manufacturing process to make the electronic component itself airtight. SUMMARY OF THE INVENTION In view of these circumstances, an object of the present invention is to provide an electronic circuit device that can easily realize high-density packaging and an airtight structure, and a method for manufacturing the same.

In order to achieve the above object, an electronic circuit device according to claim 1 of the present application includes a mounting board including a mounting surface, a wall section continuous with the mounting surface and having a U-shaped cross section, and the mounting board. a first electronic component mounted on one surface between the walls, a sealing resin filled between the walls and covering the first electronic component, and the other surface of the mounting board. a second electronic component mounted on the wall, a side surface perpendicular to the wall is partially or entirely made of the sealing resin, and the first electronic component is mounted on the surface of the wall. The device is characterized in that an electrode connected to the component or the second electronic component is exposed , and the first electronic component is an all-solid-state battery .

A method for manufacturing an electronic circuit device according to claim 2 of the present application includes the steps of: preparing a collective substrate having a recessed portion in a region where electronic circuit devices arranged in a row are to be formed; a step of forming an internal wiring continuous to an external extraction electrode; a step of mounting a first electronic component on the bottom of the recess; and a step of injecting a resin into the recess and sealing the first electronic component with the resin. a step of mounting a second electronic component on the other surface of the collective substrate, and a step of mounting the first electronic component and the second electronic component on the other surface of the collective substrate; The method is characterized in that it includes a step of separating each electronic circuit device into individual pieces each having an exposed external extraction electrode .

In the method for manufacturing an electronic circuit device according to claim 3 of the present application, in the method for manufacturing an electronic circuit device according to claim 2, when forming a recess in the collective substrate, the recess is perpendicular to the wall of the recess and a notch is formed in a part. and a step of cutting and removing part or all of the other wall during the individualization.

A method of manufacturing an electronic circuit device according to claim 4 of the present application is the method of manufacturing an electronic circuit device according to claim 2 or 3, characterized in that an all-solid-state battery is mounted as the first electronic component .

INDUSTRIAL APPLICABILITY The present invention can provide an electronic circuit device that is capable of high-density mounting and that allows electronic components to be easily and airtightly mounted, and that can be easily manufactured without going through a complicated manufacturing process. can.

In particular, the present invention enables electronic components that require airtight mounting, such as all-solid-state batteries, to be hermetically sealed by simply sealing them with a sealing resin, making it possible to very easily and easily encapsulate electronic circuits equipped with all-solid-state batteries. It becomes possible to form a device. On the other hand, electronic components that do not require airtight mounting can be mounted exposed on the mounting board, which has the advantage that parts can be easily replaced.

In the present invention, the external lead electrode can be easily formed by providing a wall portion that is continuous with the mounting board. Furthermore, by selecting a material that has a coefficient of thermal expansion equal to or close to that of the motherboard or the like on which the electronic circuit device is mounted, reliability can also be improved.

Furthermore, if another wall part is formed that protrudes from one side to the other side at a position perpendicular to the wall parts at both ends, the interval between the recesses can be narrowed, so that a large number of electronic circuit devices can be mounted on the collective board. It becomes possible to form. Since this separate wall part has a notch in part, it has the advantage of being able to suppress variations in the thickness of the resin injected during the manufacturing process.

FIG. 3 is a diagram illustrating a manufacturing process of an electronic circuit device according to a first embodiment of the present invention. FIG. 3 is a diagram illustrating a manufacturing process of an electronic circuit device according to a first embodiment of the present invention. FIG. 3 is a diagram illustrating a manufacturing process of an electronic circuit device according to a first embodiment of the present invention. FIG. 3 is a diagram illustrating a manufacturing process of an electronic circuit device according to a first embodiment of the present invention. FIG. 3 is a diagram illustrating a manufacturing process of an electronic circuit device according to a first embodiment of the present invention. FIG. 1 is an explanatory diagram of an electronic circuit device according to a first embodiment of the present invention. FIG. 7 is a diagram illustrating a manufacturing process of an electronic circuit device according to a second embodiment of the present invention. FIG. 7 is a diagram illustrating a manufacturing process of an electronic circuit device according to a second embodiment of the present invention. FIG. 3 is an explanatory diagram of an electronic circuit device according to a second embodiment of the present invention. It is a figure explaining the manufacturing process of the electronic circuit device of the 3rd Example of this invention. FIG. 7 is an explanatory diagram of an electronic circuit device according to a third embodiment of the present invention. FIG. 7 is an explanatory diagram of an electronic circuit device according to a fourth embodiment of the present invention.

The electronic circuit device and the manufacturing method thereof of the present invention relate to an invention that allows electronic components that are required to be mounted in an airtight state and electronic components that are not required to be mounted in an airtight state to be mounted with high density. Examples of the present invention will be described in detail below.

A first embodiment of the present invention will be described according to its manufacturing process. First, a collective substrate 1 made of epoxy resin or the like is prepared. As this type of collective substrate 1, a resin substrate (organic substrate) used in a normal semiconductor device manufacturing process can be used. It is preferable to select the collective board appropriately depending on the material of the mother board on which the electronic circuit device to be completed is mounted. For example, if a material with the same or similar coefficient of thermal expansion is selected, mounting reliability can be improved. can.

FIG. 1 is an explanatory diagram of a collective substrate in which a recess 2 is formed, with FIG. 1(a) showing a cross-sectional view and FIG. 1(b) showing a plan view. In FIG. 1, it is assumed that four electronic circuit devices are formed according to the steps described below. The collective substrate 1 with the recesses 2 shown in FIG. Accordingly, the through hole 4, the electrode 5, and internal wiring (not shown) connected to the electrode 5 can be formed and prepared.

As shown in FIG. 1(a), wall portions 3 are formed at both ends of the recess 2. As shown in FIG. The through hole 4 has a circular or horizontally elongated oval shape. The diameter of the through hole 4 is about 200 μm, and the thickness of the collective substrate 1 (thickness of the wall portion 3) between the recess 2 and the through hole 4 is about 0.5 mm to 1.0 mm, so that the strength of the collective substrate 1 can be maintained. Can be done.

Next, as shown in FIG. 2, the electronic component 6a is mounted in the recess 2. Wiring for connecting to the electronic component 6a is formed on the bottom surface of the recess 2, and the electronic component 6a is connected by a desired method. At this time, since there is no wall or the like between the recess 2 and the area where the adjacent electronic circuit device is to be formed, it is easy to drop adhesive material to the bottom of the recess 2 for mounting and to transport electronic components. can be done. In particular, by applying a method of applying solder to the bottom surface of the recess 2 using a dispenser when dropping the adhesive material, it is possible to reliably supply the adhesive material such as solder to the bottom surface of the deep recess 2. This is preferable because reliability can be ensured. Furthermore, it becomes possible to easily mount a plurality of electronic components within the recess 2.

The electronic component 6a to be mounted in the recess 2 can be selected from among the electronic components to be mounted in an airtight state. For example, all-solid-state batteries can be selected. Generally, the characteristics of all-solid-state batteries deteriorate due to moisture in the atmosphere. Therefore, in order to prevent such characteristic deterioration, as shown in FIG. 3, a sealing resin 7 such as an epoxy resin is filled into the recess 2 and sealed with the resin. In order to maintain sufficient airtightness, it is necessary to sufficiently cover the surface of the electronic component 6a with the sealing resin 7. Therefore, it is preferable that the depth of the recess 2 (in other words, the height of the wall 3) is deeper (higher) than the height of the electronic component 6a mounted on the collective substrate 1. Specifically, when the height of the electronic component 5a is 0.6 mm, by setting the height of the wall 3 of the recess 2 to about 0.8 mm, it is possible to mount the electronic component 6a on the bottom of the recess 2. Even if variations in the height of the adhesive member occur, an airtight structure that does not allow moisture to enter can be formed. If it is necessary to form the sealing resin 7 thicker to form an airtight structure, the thickness of the frame plate 1b may be appropriately selected in consideration of its thickness, the height of the electronic component 6a, etc.

Although FIG. 2 shows an example in which two electronic components 6a that are required to be mounted in an airtight state are mounted, other types of electronic components that are not required to be mounted in an airtight state may be mounted in combination.

In this way, the surface of the collective substrate 1 is flattened by the sealing resin 7 (FIG. 3). The sealing resin 7 used preferably has a viscosity of about 100 Pa·s or less so that it can be flattened by dropping it from a dispenser. Furthermore, in consideration of chemical resistance, reflow resistance, etc., it is preferable to select, for example, epoxy resin. By increasing the amount of filler such as silicon dioxide (for example, about 60 wt% or more) and using a resin whose water absorption is about 0.3 wt% or less, it is possible to implement airtight mounting. When mounting the electronic component 6a using solder, a process of removing flux may be added. Note that this planarization is suitable for proceeding with the manufacturing process described later even if none of the electronic components to be mounted requires hermetic sealing.

After that, another electronic component is mounted on the back surface (corresponding to the other surface) of the collective substrate 1. In the example shown in FIG. 4, three electronic components 6b, 6c, and 6d are mounted.

As shown in FIG. 4, in this type of electronic circuit device, electronic components of various sizes are mounted on a collective substrate 1. In such a case, if the electronic components 6b to 6d on the back side are mounted and then the electronic components 6a on the front side are mounted and resin-sealed, the electronic components 6b to 6d may fall off. Therefore, as described above, it is preferable to mount the electronic component 6a on the front side and perform resin sealing first. Of course, the process can be reversed as long as no electronic components fall off.

Next, the assembled substrate is separated into individual pieces. This singulation is performed so that the electrodes 5 are exposed on the outer periphery of the electronic circuit device. Specifically, as shown in FIG. 5, this is carried out by running, for example, a dicing saw in a grid pattern passing through the center of the through hole 4. As a result, the wall portions 3 of the collective substrate 1 remain at both ends in the left-right direction in the drawing. On the other hand, no side walls of the recess 2 remain at both ends in the vertical direction of the drawing. In the example shown in FIG. 5, the electronic circuit devices are separated into four pieces. Generally, the singulation process is carried out by pasting the collective substrate onto a sheet for fixing it, so by flattening the back surface of the collective substrate, the collective substrate or the electronic circuit device after singulation can be attached to the sheet. This is preferable because it can be reliably adhered to. Furthermore, it is preferable that the back surface of the collective substrate is flat because cutting debris will not enter the gap between the wall portion 3 and the electronic component 6a.

FIG. 6 shows a perspective view of the electronic circuit device after being singulated. As shown in FIG. 6, in the singulated electronic circuit device, a plurality of electronic components 6b, 6c, and 6d are mounted on a mounting board 8 in which the collective board is separated into pieces, and the electronic circuit device is mounted on the opposite side of the mounting board 8. , an electronic component 6a is covered with a sealing resin 7. Further, on the wall portion 3, an electrode 5 for external extraction of the electronic circuit device (corresponding to an external extraction electrode) is exposed.

The electronic circuit device of this embodiment can mount a plurality of electronic components 6a to 6d at high density, and when the electronic component 6a is required to be mounted in an airtight state, it can be covered with a sealing resin. It can be hermetically sealed. In addition, since the electrode 5 is structured to be exposed on the side wall of the electronic circuit device, when mounting the electronic circuit device, connection materials such as solder creep up the side wall of the electrode 5, making it impossible to form a reliable connection. This also facilitates visual inspection.

Next, a second embodiment will be described. Although the first embodiment has a structure in which the electrode 5 is exposed on the side wall of the electronic circuit device, it is also possible to change the electrode structure.

Specifically, the shape of the collective substrate 1 is changed. FIG. 7 is a diagram corresponding to FIG. 1 described in the first embodiment. It can be seen that the shape of the electrode 5a is different from that in FIG. In this embodiment, a circular through hole 4a is formed in the collective substrate 1 in which the recess 2 is formed, for example, by drilling or router processing. The through hole 4a of this embodiment is formed to have a smaller diameter than the through hole 4 described in the first embodiment. Thereafter, the electrodes 5a can be formed by filling conductive paste or the like and forming surface electrodes on the front and back surfaces of the collective substrate.

Thereafter, as in the first embodiment, the electronic component 6a is mounted in the recess 2, and the recess 2 is filled with the sealing resin 7 to be resin-sealed. Thereafter, other electronic components 6b, 6c, and 6d are mounted on the back surface (front side in FIG. 8) of the collective substrate 1 and separated into individual pieces. This singulation process is carried out by running, for example, a dicing saw in a grid pattern passing through positions where there are no through holes 5a as shown in FIG.

As a result, an electronic circuit device whose perspective view is shown in FIG. 9 is completed. In the electronic circuit device having such a shape, the electrodes 5a are not exposed on the outer circumference but only on the front and back surfaces of the mounting board 8, so that higher density mounting is possible.

Next, a third embodiment will be described. In the first and second embodiments described above, the recess 2 formed in the collective substrate 1 has a vertically elongated shape. Here, in order to increase the number of electronic circuit devices that can be formed from the collective substrate 1, if the interval between adjacent recesses 2 is narrowed, a part of the collective substrate 1 that constitutes the wall remaining between the recesses 2 will be deformed. There is a risk of it getting lost. Therefore, it is also possible to change the shape of the recess 2.

FIG. 10 is a diagram corresponding to FIG. 1 described in the first embodiment. As shown in FIG. 10, a protrusion 9 (corresponding to another wall) can be formed within the recess 2. By arranging this protrusion 9 at a position that will be a cutting area during singulation, it will not affect the area where electronic components are mounted. Note that the protruding portion 9 extends from one wall portion 3, and a gap is provided between its tip and the opposing wall portion 3. This is to make the thickness of the sealing resin in the recess 2 uniform when the sealing resin is dropped into the recess 2 as explained in FIG. 3, for example.

The protrusion 9 may be formed by, for example, router processing so that the protrusion 9 remains when the recess 2 is formed.

Thereafter, as in the first embodiment, the electronic component 6a is mounted in the recess 2, and the recess 2 is filled with sealing resin 7 and sealed. Thereafter, other electronic components 6b, 6c, and 6d are mounted on the back surface (front side in FIG. 7) of the collective substrate 1 and separated into individual pieces. This separation is performed by running a dicing saw, for example, in a grid pattern passing through the center of the through hole 5 shown in FIG.

If the width of the protrusion 9 is made narrower than the width cut and removed by the dicing saw, the protrusion 9 will be cut and removed during the singulation, and an electronic circuit device having the shape shown in FIG. 6 will be completed. In this case, the mounting board has a U-shaped wall continuous to the mounting surface, and the side surface perpendicular to this has a structure in which the entire wall continuous to the mounting surface is cut out. Further, by making the width of the protrusion 9 wider than the width to be removed and leaving a portion of the protrusion 9, an electronic circuit device having the shape shown in FIG. 11 is completed. In this case, the mounting board has a U-shaped side surface that is continuous with the mounting surface, and the side surface that is perpendicular to the U-shaped side surface has a structure in which a part of the wall that is continuous with the mounting surface is cut out.

The arrangement of the protrusions 9 is not limited to the case shown in FIG. 10. For example, if the length of the recess 2 is long and it is necessary to form a plurality of protrusions 9, the protrusions 9 may be arranged so that they protrude from one wall toward the opposing wall, or they may be arranged so that they protrude from both walls alternately. Various modifications are possible, such as an arrangement in which the protrusions protrude toward the wall (staggered structure), or a change in the arrangement of the protrusions arranged in adjacent recesses. In particular, when all the protrusions 9 are removed during singulation, no protrusions 9 remain in the completed electronic circuit device, so various modifications are possible. On the other hand, if a portion of the protrusion 9 remains, the arrangement of the protrusion 9 must be determined by considering where in the completed electronic circuit device the protrusion 9 will remain.

The height of the protrusion 9 can also be changed as appropriate, and if there is a problem such as contact with the dispenser when dropping the adhesive member into the recess 2, the height of the protrusion 9 can be lowered. . If the width of the protruding portion 9 is made narrower than the width to be cut and removed, the protruding portion 9 can be cut and removed during singulation, and an electronic circuit device having the shape shown in FIG. 6 can be completed. In this case, the mounting board has a U-shaped wall continuous to the mounting surface, and the side surface perpendicular to this has a structure in which the entire wall continuous to the mounting surface is cut out. Further, by making the width of the protrusion 9 wider than the width to be removed and leaving a portion of the protrusion 9, an electronic circuit device having the shape shown in FIG. 12 is completed. In this case, the mounting board has a U-shaped side surface that is continuous with the mounting surface, and the side surface that is perpendicular to the U-shaped side surface has a structure in which a part of the wall that is continuous with the mounting surface is cut out.

The above description has been made as a modification of the electronic circuit device described in the first embodiment, but it goes without saying that it is applicable to the second embodiment, which has a different electrode structure.

Although the embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to these embodiments. For example, the shape of the electrode 5 can be changed as appropriate depending on the connection structure with the motherboard on which the electronic circuit device is mounted. Further, the number of electrodes 5 can be changed as appropriate depending on the electronic components and circuit configuration mounted on the electronic circuit device. Furthermore, the number of electronic components mounted on the electronic circuit device can also be changed as appropriate.

1: Collective board, 1a: Double-sided board, 1b: Frame board, 2: Recess, 3: Wall, 4, 4a: Through hole, 5: Electrode, 6a to 6d: Electronic component, 7: Sealing resin, 8: Mounting board, 9: Protrusion part

Claims (4)

a mounting board comprising a mounting surface and a wall portion continuous with the mounting surface and having a U-shaped cross section;
a first electronic component mounted on one surface between the walls of the mounting board;
a sealing resin filled between the wall portions and covering the first electronic component;
a second electronic component mounted on the other surface of the mounting board,
A side surface perpendicular to the wall portion is partially or entirely composed of the sealing resin;
an electrode connected to the first electronic component or the second electronic component is exposed on the surface of the wall ;
An electronic circuit device , wherein the first electronic component is an all-solid-state battery . preparing a collective substrate having recesses in areas where electronic circuit devices arranged in rows are to be formed;
forming an external lead electrode and an internal wiring continuous to the external lead electrode on the collective substrate;
mounting a first electronic component on the bottom of the recess;
Injecting a resin into the recess and sealing the first electronic component with the resin;
mounting a second electronic component on the other surface of the collective substrate;
A step of separating into individual electronic circuit devices each including the first electronic component and the second electronic component sealed with resin and having external extraction electrodes exposed on the surface of the collective substrate. A method for manufacturing an electronic circuit device. The method for manufacturing an electronic circuit device according to claim 2,
When forming a recess in the collective substrate, forming another wall that is perpendicular to the wall of the recess and has a notch in a part;
A method for manufacturing an electronic circuit device, comprising the step of cutting and removing part or all of the other wall portion during the individualization . The method for manufacturing an electronic circuit device according to claim 2 or 3 ,
A method of manufacturing an electronic circuit device, characterized in that an all-solid-state battery is mounted as the first electronic component .

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