JP7438656B2 - collective board - Google Patents

Description

This disclosure relates to a collective substrate in which a plurality of ceramic multilayer substrates are integrally formed.

In recent years, miniaturization of circuit modules used in small mobile communication devices and the like has been progressing. Therefore, there is a need to reduce the thickness of ceramic multilayer substrates used in circuit modules. On the other hand, reducing the thickness of the multilayer ceramic substrate leads to a decrease in the strength of the aggregate substrate, which is an aggregate thereof. As a result, there is a possibility that cracks or chips may occur in the aggregate substrate during various processes in which the aggregate substrate is handled.

An interesting technique for reducing cracks or chips in such a collective substrate is described in International Publication No. 2011/152085 (Patent Document 1). The collective substrate described in Patent Document 1 includes a substrate region including a portion that becomes an individual ceramic multilayer substrate including a dielectric layer, a pattern conductor, and a via conductor, a peripheral region surrounding the substrate region, and a peripheral region. and a shrinkage suppressing layer formed on. Here, the shrinkage suppressing layer is provided in each layer of the ceramic green sheets before lamination. Moreover, it is preferable that the shrinkage suppressing layer is formed of the same material as the patterned conductor.

International Publication No. 2011/152085

In the collective substrate described in Patent Document 1, the shrinkage suppressing layer formed in the peripheral region can suppress a decrease in strength of the collective substrate. On the other hand, the shrinkage suppressing layers are formed in the peripheral area of each layer of the ceramic green sheets before lamination so as to be stacked on top of each other. Therefore, when the ceramic green sheets are stacked and pressure-bonded, pressure is applied preferentially to the peripheral region that is thicker due to the inclusion of the shrinkage suppressing layer.

Therefore, the pressure applied to the substrate region is relatively small compared to the pressure applied to the peripheral region. As a result, the pressure bonding of the substrate region becomes insufficient, and there is a possibility that structural defects such as delamination may occur in the substrate region.

That is, an object of this disclosure is to provide an aggregate substrate that can suppress a decrease in strength even when the thickness is reduced, and can suppress structural defects in the substrate region.

In the collective substrate according to this disclosure, the structure of the peripheral region is improved.

An aggregate substrate according to this disclosure includes an aggregate substrate body having a first main surface, a second main surface, and a side surface connecting the first main surface and the second main surface, and a first resin It is equipped with a membrane. The collective substrate element includes a substrate region including portions that become individual ceramic multilayer substrates by being divided, and a peripheral region integrally formed with the substrate region so as to surround the substrate region. The first resin film is provided in at least a portion of the peripheral region of the first main surface so as to surround the substrate region.

Since the collective substrate according to this disclosure has the above structure, it is possible to suppress a decrease in strength even when the thickness is reduced, and it is possible to suppress structural defects in the substrate region.

FIG. 1(A) is a perspective view of the collective substrate 100. FIG. 1(B) is a cross-sectional view of the collective substrate 100 taken along the A1 plane. FIG. 2(A) is a cross-sectional view of an aggregate substrate 100A, which is a first modified example of the aggregate substrate 100. FIG. 2(B) is a cross-sectional view of an aggregate substrate 100B, which is a second modification example of the aggregate substrate 100. 7 is a perspective view of a collective substrate 100C which is a third modification example of the collective substrate 100. FIG. FIG. 4(A) is a perspective view of the collective substrate 200. FIG. 4(B) is a cross-sectional view of the collective substrate 200 taken along the A2 plane. FIG. 5(A) is a cross-sectional view of an aggregate substrate 200A, which is a first modified example of the aggregate substrate 200. FIG. 5(B) is a cross-sectional view of an aggregate substrate 200B, which is a second modification example of the aggregate substrate 200. FIG. 6(A) is a perspective view of the collective substrate 300. FIG. 6(B) is a cross-sectional view of the collective substrate 300 taken along the A3 plane. FIG. 7(A) is a cross-sectional view of an aggregate substrate 300A that is a first modification example of the aggregate substrate 300. FIG. 7(B) is a cross-sectional view of an aggregate substrate 300B, which is a second modified example of the aggregate substrate 300.

Features of this disclosure will be described based on embodiments of this disclosure with reference to the drawings. In the embodiments described below, the same or common parts are denoted by the same reference numerals in the figures, and the description thereof may not be repeated.

-First embodiment of collective board-
A collective substrate 100, which is a first embodiment of a collective substrate according to this disclosure, will be described using FIG. 1.

FIG. 1(A) is a perspective view of the collective substrate 100. Further, FIG. 1(B) is a cross-sectional view of the collective substrate 100 taken along the A1 plane. The collective substrate 100 has a first main surface S1 (top surface), a second main surface S2 (bottom surface), and a side surface S3 connecting the first main surface S1 and the second main surface S2. It includes a substrate body 10 and a first resin film 20.

The aggregate substrate body 10 is obtained by firing under predetermined conditions a crimped body obtained by laminating and crimping ceramic green sheets on which at least one of a pre-fired pattern conductor and a pre-fired via conductor is formed as required. can get. The stacking direction of the green sheets is a direction perpendicular to the pattern conductor.

That is, the aggregate substrate element 10 includes a dielectric layer 11 formed by firing a ceramic green sheet, a pattern conductor 12, and a via conductor 13. The pattern conductor 12 includes, in each ceramic multilayer substrate 1, a first pattern conductor 12a that constitutes circuit wiring and circuit elements, and a second pattern conductor 12b that is connected to the ground. The second pattern conductor 12b is formed as a pattern on the entire surface of the ceramic multilayer substrate 1.

For the dielectric layer 11, for example, a low-temperature sintered ceramic material is used. For the pattern conductor 12 and the via conductor 13, a metal material selected from, for example, Cu and a Cu alloy is used. Note that the pattern conductor 12 may include a base layer using the above metal material and a plating film such as Ni plating or Au plating formed on the base layer. The above materials and configurations are merely examples, and are not limited thereto.

The collective substrate element 10 is divided into a substrate area 10a (shaded area in FIG. 1(A)) including parts that will become individual ceramic multilayer substrates 1, and is integrated with the substrate area 10a so as to surround the substrate area 10a. It includes a peripheral region 10b formed into a. The peripheral region 10b is a region surrounded by dotted lines on both sides of the substrate region 10a in FIG. 1(B). The substrate region 10a and the peripheral region 10b are integrally formed by firing a laminate in which ceramic green sheets including regions corresponding to the substrate region 10a and the peripheral region 10b are laminated and pressed together as described above. be done.

A first electrode group 14 is arranged in the substrate region 10a on the first main surface S1. The first electrode group 14 becomes a land to which electronic components are connected in each ceramic multilayer substrate 1 obtained after dividing the collective substrate 100. On the other hand, a second electrode group 15 is arranged in the substrate region 10a on the second main surface S2. The second electrode group 15 serves as an external electrode when the circuit module is connected to a motherboard of an electronic device or the like in a circuit module in which electronic components are connected to the ceramic multilayer substrate 1.

The first resin film 20 is provided in a frame shape in the peripheral region 10b of the first main surface S1 so as to surround the substrate region 10a.

As the first resin film 20, for example, epoxy resin, polyimide resin, polyamide resin, and those obtained by adding additives to these resins can be used. The first resin film 20 is formed by applying a liquid precursor of the resin described above to the peripheral region 10b of the first main surface S1 by a coating method such as screen printing or an inkjet method, and then converting it into a solid resin by heating or the like. It is formed by The above-mentioned materials and forming means are merely examples, and the present invention is not limited thereto.

In the collective substrate 100, the first resin film 20 is provided in the peripheral region 10b on the first main surface S1 so as to surround the substrate region 10a. That is, the peripheral region 10b is reinforced by the first resin film 20. Therefore, it is possible to suppress a decrease in strength due to a reduction in the thickness of the aggregate substrate 100 (the aggregate substrate element 10).

Further, the first resin film 20 is formed in the state of the aggregate substrate element body 10 after firing. That is, the aggregated substrate element 10 has a means for suppressing a decrease in the strength of the aggregated substrate, such as the shrinkage suppressing layer described in Patent Document 1 mentioned above, inside the peripheral region 10b of the aggregated substrate element 10. You don't need to prepare.

Therefore, in the manufacturing process of the aggregate substrate body 10, when the ceramic green sheets are stacked and pressure-bonded, it is possible to suppress a relative decrease in the pressure applied to the substrate region 10a with respect to the pressure applied to the peripheral region 10b. As a result, the substrate region 10a is sufficiently compressed, and the occurrence of structural defects in the substrate region 10a can be suppressed.

Note that in the collective substrate 100, in addition to the first resin film 20, a second resin film 30 is provided in a frame shape in the peripheral region 10b of the second main surface S2 so as to surround the substrate region 10a. . That is, the peripheral region 10b is further reinforced by the second resin film 30. Therefore, it is possible to further suppress a decrease in strength due to a reduction in the thickness of the collective substrate 100 (the collective substrate body 10).

As the second resin film 30, for example, epoxy resin, polyimide resin, polyamide resin, and those obtained by adding additives to these resins can be used. The second resin film 30 is formed by applying a liquid precursor of the above resin to the peripheral region 10b of the second main surface S2 by a coating method such as screen printing or an inkjet method, and then converting it into a solid resin by heating or the like. It is formed by The first resin film 20 and the second resin film 30 may be formed of the same material or may be formed of different materials. The above-mentioned materials and forming means are merely examples, and the present invention is not limited thereto.

In addition, in the collective substrate 100, the first resin film 20 and the second resin film 30 are formed to have the same shape and the same position when viewed from the normal direction of the first main surface S1. . However, it is not essential that the first resin film 20 and the second resin film 30 be formed in the same shape and at the same position.

In the collective substrate 100, the pattern conductor 16 is arranged inside the peripheral region 10b. The pattern conductor 16 includes a third pattern conductor 16a and a fourth pattern conductor 16b. The third pattern conductor 16a is a dummy conductor that does not constitute circuit wiring or circuit elements, and is arranged so that the portions that overlap each other are reduced, as in the staggered arrangement illustrated in the cross-sectional view of FIG. 1B. It's a pattern. Note that the arrangement of the third pattern conductor 16a is not limited to this. The fourth pattern conductor 16b is a part of the second pattern conductor 12b described above.

Since the third pattern conductor 16a is arranged as described above, it suppresses an increase in the thickness of the peripheral region 10b when the ceramic green sheets are laminated and crimped in the manufacturing process of the aggregate substrate element 10. be able to. As a result, it is possible to suppress a relative decrease in the pressure applied to the substrate region 10a with respect to the pressure applied to the peripheral region 10b. Moreover, since the fourth pattern conductor 16b is a part of the second pattern conductor 12b, it does not increase only the thickness of the peripheral region 10b.

Therefore, the arrangement of the patterned conductor 16 inside the peripheral region 10b can further improve the strength of the collective substrate 100 while suppressing an increase in structural defects in the substrate region 10a.

- Modification of the first embodiment of the collective board -
Collective substrates 100A to 100C, which are modified examples of the first embodiment of the collective substrate according to this disclosure, will be described using FIGS. 2 and 3.

FIG. 2(A) is a cross-sectional view of an aggregate substrate 100A, which is a first modified example of the aggregate substrate 100. FIG. 2(B) is a cross-sectional view of an aggregate substrate 100B, which is a second modification example of the aggregate substrate 100. The sectional views shown in FIGS. 2(A) and 2(B) correspond to the sectional view taken in the direction of the arrows shown in FIG. 1(B). FIG. 3 is a perspective view of a collective substrate 100C, which is a third modified example of the collective substrate 100.

The collective substrates 100A to 100C are different from the collective substrate 100 in the resin film provided in the peripheral region 10b. The rest of the configuration is the same as that of the collective substrate 100, so a detailed explanation will be omitted.

In the collective substrate 100A, which is the first modification, the first resin film 20 is provided in a frame shape in the peripheral region 10b of the first main surface S1 so as to surround the substrate region 10a. The resin film 30 is not provided. Also in this case, as described above, it is possible to suppress a decrease in strength due to a reduction in thickness, and it is possible to suppress structural defects in the substrate region 10a.

In the collective substrate 100B that is the second modification, in addition to the first resin film 20 and the second resin film 30, a third resin film 40 is provided so as to cover the side surface S3. Further, the first resin film 20 and the second resin film 30 are connected via a third resin film 40.

By providing the third resin film 40 to cover the side surface S3, in addition to suppressing the decrease in strength due to the reduction in the thickness described above, damage to the aggregate substrate element 10 due to impact applied to the side surface S3 is suppressed. be able to. In addition, like the collective substrate 100B, the first resin film 20 and the second resin film 30 are connected via the third resin film 40, so that the collective substrate element is particularly susceptible to chipping due to impact. 10 corners are covered with a resin film. As a result, damage to the aggregate substrate element 10 due to impact applied to the corner can be suppressed.

Note that in the collective substrate 100B, the first resin film 20 and the second resin film 30 are formed to have the same shape and the same position when viewed from the normal direction of the first main surface S1. is not required.

Also in the collective substrate 100C, which is the third modification, the first resin film 20 is provided in the peripheral region 10b of the first main surface S1 so as to surround the substrate region 10a. Further, the second resin film 30 is provided in the peripheral region 10b of the second main surface S2 so as to surround the substrate region 10a. However, in the first resin film 20 and the second resin film 30 in the collective substrate 100C, short strip-shaped resin films are arranged at intervals in the shape of a broken line.

Even in this case, as described above, it is possible to suppress a decrease in strength due to a reduction in thickness, and it is possible to suppress structural defects in the substrate region. Note that also in the collective substrate 100C, the first resin film 20 and the second resin film 30 are formed to have the same shape and the same position when viewed from the normal direction of the first main surface S1. That is not necessary.

-Second embodiment of collective board-
A collective substrate 200, which is a second embodiment of the collective substrate according to this disclosure, will be described using FIG. 4.

FIG. 4(A) is a perspective view of the collective substrate 200. Further, FIG. 4(B) is a cross-sectional view of the collective substrate 200 taken along the A2 plane. The collective substrate 200 differs from the collective substrate 100 in the resin film provided in the peripheral region 10b so as to surround the substrate region 10a (the shaded area in FIG. 4(A)). The rest of the configuration is the same as that of the collective substrate 100, so detailed explanation will be omitted.

In the collective substrate 200, the first resin film 20 includes a frame-shaped first portion 20a, a second portion 20b, and a third portion 20c, which are formed at intervals. Note that the first resin film 20 only needs to include two parts, a first part 20a and a second part 20b, which are formed with an interval between them.

Also in this case, as described above, it is possible to suppress a decrease in strength due to a reduction in thickness, and it is possible to suppress structural defects in the substrate region 10a. Further, by reducing the amount of the first resin film 20, the manufacturing cost of the collective substrate 200 can be reduced.

The first resin film 20 on the collective substrate 200 can be formed, for example, by applying a liquid resin precursor using an inkjet method. Since the first resin film 20 including the first portion 20a and the second portion 20b having a narrow line width is formed by an inkjet method, it is possible to suppress the impact applied to the aggregate substrate element 10 during formation.

Note that in the collective substrate 200, in addition to the first resin film 20, a second resin film 30 is provided in a frame shape in the peripheral region 10b of the second main surface S2 so as to surround the substrate region 10a. . The second resin film 30 includes a first portion 30a, a second portion 30b, and a third portion 30c formed at intervals. The second resin film 30 only needs to include two parts, a first part 30a and a second part 30b, which are spaced apart from each other.

That is, the peripheral region 10b is further reinforced by the second resin film 30. Therefore, it is possible to further suppress a decrease in strength due to a reduction in the thickness of the collective substrate 200 (the collective substrate body 10).

Note that in the collective substrate 200, the first resin film 20 and the second resin film 30 are formed to have the same shape and the same position when viewed from the normal direction of the first main surface S1. is not required. Further, the first to third portions of each resin film may be short strip-shaped resin films arranged in a broken line shape at intervals, as in the collective substrate 100C. Further, in the collective substrate 200 as well, the pattern conductor 16 may be arranged inside the peripheral region 10b.

- Modification of the second embodiment of the collective board -
Collective substrates 200A and 200B, which are modified examples of the second embodiment of the collective substrate according to this disclosure, will be described using FIG. 5.

FIG. 5(A) is a cross-sectional view of an aggregate substrate 200A, which is a first modified example of the aggregate substrate 200. FIG. 5(B) is a cross-sectional view of an aggregate substrate 200B, which is a second modification example of the aggregate substrate 200. The cross-sectional views shown in FIGS. 5A and 5B correspond to the cross-sectional view taken in the direction of the arrows shown in FIG. 4B.

The collective substrates 200A and 200B are different from the collective substrate 200 in the resin film provided in the peripheral region 10b. The rest of the configuration is the same as that of the collective substrate 200, so a detailed explanation will be omitted.

In the collective substrate 200A, which is the first modification, the first resin film 20 is provided in a frame shape in the peripheral region 10b of the first main surface S1 so as to surround the substrate region 10a. The resin film 30 is not provided. Even in this case, as described above, it is possible to suppress a decrease in strength due to a reduction in thickness, and it is possible to suppress structural defects in the substrate region.

In the collective substrate 200B that is the second modification, in addition to the first resin film 20 and the second resin film 30, a third resin film 40 is provided so as to cover the side surface S3. Further, the first resin film 20 (third portion 20c) and the second resin film 30 (third portion 30c) are connected via a third resin film 40.

By providing the third resin film 40 to cover the side surface S3, in addition to suppressing the decrease in strength due to the reduction in the thickness described above, damage to the aggregate substrate element 10 due to impact applied to the side surface S3 is suppressed. be able to. In addition, like the collective substrate 200B, the first resin film 20 and the second resin film 30 are connected via the third resin film 40, so that the collective substrate element is particularly susceptible to chipping due to impact. 10 corners are covered with a resin film. As a result, damage to the aggregate substrate element 10 due to impact applied to the corner can be suppressed.

Note that in the collective substrate 200B, the first resin film 20 and the second resin film 30 are formed to have the same shape and the same position when viewed from the normal direction of the first main surface S1. is not required.

-Third embodiment of collective board-
A collective substrate 300, which is a second embodiment of the collective substrate according to this disclosure, will be described using FIG. 6.

FIG. 6(A) is a perspective view of the collective substrate 300. Further, FIG. 6(B) is a cross-sectional view of the collective substrate 300 taken along the A3 plane. The collective substrate 300 also differs from the collective substrate 100 in the resin film provided in the peripheral region 10b so as to surround the substrate region 10a (the shaded area in FIG. 6(A)). The rest of the configuration is the same as that of the collective substrate 100, so a detailed explanation will be omitted.

In the collective substrate 300, the first resin film 20 covers the first main surface S1 while exposing the first electrode group 14 arranged in the substrate region 10a on the first main surface S1. It is provided. Further, the first resin film 20 is a resist film. Examples of this resist film include a solder resist that is applied on the first main surface S1 in order to prevent short circuits due to solder bridges when electronic components are soldered to the first electrode group 14, for example.

Also in this case, as described above, it is possible to suppress a decrease in strength due to a reduction in thickness, and it is possible to suppress structural defects in the substrate region 10a. Further, by using a resist film such as a solder resist as the first resin film 20, it is not necessary to separately form the resist film and the first resin film 20, and the manufacturing process can be simplified.

The first resin film 20 on the collective substrate 300 can be formed, for example, by applying a liquid resin precursor by spin coating and patterning by photolithography. In this case, the first resin film 20 can be efficiently formed to cover the first main surface S1 with the first electrode group 14 exposed.

Note that in the collective substrate 300, in addition to the first resin film 20, the second resin film 30 exposes the second electrode group 15 disposed in the substrate region 10a on the second main surface S2. is provided so as to cover the second main surface S2. Like the first resin film 20, the second resin film 30 is also a resist film such as a solder resist film.

That is, the peripheral region 10b is further reinforced by the second resin film 30. Therefore, it is possible to further suppress a decrease in strength due to a reduction in the thickness of the collective substrate 300 (the collective substrate body 10).

Note that in the collective substrate 300 as well, the pattern conductor 16 may be arranged inside the peripheral region 10b.

- Modification of the third embodiment of the collective board -
Collective substrates 300A and 300B, which are modified examples of the second embodiment of the collective substrate according to this disclosure, will be described using FIG. 7.

FIG. 7(A) is a cross-sectional view of an aggregate substrate 300A that is a first modification example of the aggregate substrate 300. FIG. 7(B) is a cross-sectional view of an aggregate substrate 300B, which is a second modified example of the aggregate substrate 300. The cross-sectional views shown in FIGS. 7A and 7B correspond to the cross-sectional view taken in the direction of the arrows shown in FIG. 6B.

The collective substrates 300A and 300B are different from the collective substrate 300 in the resin film provided in the peripheral region 10b. The rest of the configuration is the same as that of the collective substrate 300, so a detailed explanation will be omitted.

In the collective substrate 300A, which is the first modification, the first resin film 20 is arranged on the first main surface S1 with the first electrode group 14 disposed in the substrate region 10a exposed. Although it is provided so as to cover the main surface S1, the second resin film 30 is not provided. The first resin film 20 is a resist film similarly to the collective substrate 300. Even in this case, as described above, it is possible to suppress a decrease in strength due to a reduction in thickness, and it is possible to suppress structural defects in the substrate region.

In the second modified example substrate 300B, in addition to the first resin film 20 and the second resin film 30, which are resist films, a third resin film 40 is provided to cover the side surface S3. . Further, the first resin film 20, the second resin film 30, and the third resin film 40 are made of the same material.

By providing the third resin film 40 to cover the side surface S3, in addition to suppressing the decrease in strength due to the reduction in the thickness described above, damage to the aggregate substrate element 10 due to impact applied to the side surface S3 is suppressed. be able to. In addition, like the collective substrate 300B, the first resin film 20 and the second resin film 30 are connected via the third resin film 40, so that the collective substrate element is particularly susceptible to chipping due to impact. 10 corners are covered with a resin film. In this case, each resin film is integrated. As a result, damage to the aggregate substrate element 10 due to impact applied to the corner can be suppressed.

Furthermore, with the first electrode group 14 and the second electrode group 15 exposed, the outer surface of the aggregate substrate element 10 is integrally covered with the respective resin films, thereby suppressing peeling of the resin films. can do.

The embodiments disclosed in this specification are illustrative, and the invention according to this disclosure is not limited to the above embodiments and modifications. That is, the scope of the invention according to this disclosure is indicated by the claims, and it is intended that the meaning equivalent to the claims and all changes within the range are included. Furthermore, various applications and modifications can be made within the above range.

The invention according to this disclosure is applied to an aggregate board, which is an aggregate of ceramic multilayer substrates, which is a circuit board of a circuit module, but is not limited thereto.

100 Collective substrate 1 Ceramic multilayer substrate 10 Collective substrate element 10a Substrate region 10b Peripheral region 11 Dielectric layer 12 Patterned conductor 12a First patterned conductor 12b Second patterned conductor 13 Via conductor 14 First electrode group 15 Second Electrode group 16 Pattern conductor 16a Third pattern conductor 16b Fourth pattern conductor 20 First resin film 30 Second resin film S1 First main surface S2 Second main surface S3 Side surface

Claims (7)

comprising a collective substrate element body having a first main surface, a second main surface, and a side surface connecting the first main surface and the second main surface, and a first resin film,
The collective substrate element includes a substrate region including portions that become individual ceramic multilayer substrates by being divided, and a peripheral region integrally formed with the substrate region so as to surround the substrate region,
The first resin film is provided on at least a portion of the peripheral area on the first main surface so as to surround the substrate area,
The first resin film is a film obtained by hardening a liquid precursor of the first resin film on the first main surface,
The first resin film includes a frame-shaped first part and a second part formed at intervals, and the second part is arranged on the outer peripheral side of the first part. , collective substrate. A second resin film is provided in at least a portion of the peripheral region on the second main surface so as to surround the substrate region,
The second resin film includes a frame-shaped first part and a second part formed at intervals, and the second part is arranged on the outer peripheral side of the first part. The aggregate substrate according to claim 1, characterized in that: 3. The collective substrate according to claim 2 , wherein a third resin film is provided to cover the side surface. 4. The collective substrate according to claim 3 , wherein the first resin film and the second resin film are connected via the third resin film. 5. The collective substrate according to claim 4 , wherein the third resin film is made of the same material as the first resin film and the second resin film. 2. The collective substrate according to claim 1, further comprising a third resin film provided to cover the side surface. The collective substrate according to any one of claims 1 to 6 , wherein a patterned conductor is arranged inside the peripheral area.