CN211702527U

CN211702527U - Multilayer substrate

Info

Publication number: CN211702527U
Application number: CN202020133278.7U
Authority: CN
Inventors: 多胡茂; 古村知大
Original assignee: Murata Manufacturing Co Ltd
Current assignee: Murata Manufacturing Co Ltd
Priority date: 2019-01-25
Filing date: 2020-01-20
Publication date: 2020-10-16
Anticipated expiration: 2030-01-20
Also published as: JP2020120024A; JP7234651B2

Abstract

The utility model discloses a multilayer substrate that has restrained the interlaminar peeling-off that results from residual gas in the substrate when ensureing the joint strength of insulating substrate layer faying face each other. A multilayer substrate (101) comprises: a substrate (10A) which is a laminate formed by laminating a plurality of insulating substrate layers (11 a-14 a); and conductor patterns (conductors 31-34) formed on the plurality of insulating base material layers (11 a-14 a), wherein at least one insulating base material layer (12a) of the plurality of insulating base material layers (11 a-14 a) has: and exhaust sections (NR 11-NR 14) which, when viewed in the stacking direction (Z-axis direction) of the insulating base material layers (11 a-14 a), partially overlap the planar conductor (32) that is the conductor pattern having the largest area among the conductor patterns (conductors 31-34), and extend from the inside to the outside of the planar conductor (32).

Description

Multilayer substrate

Technical Field

The present invention relates to a multilayer substrate including a base material formed by laminating a plurality of insulating base material layers and a conductor pattern formed on the base material.

Background

Conventionally, there is known a multilayer substrate including a base material formed by laminating a plurality of insulating base material layers and a conductor pattern formed on the base material.

For example, patent document 1 discloses a multilayer substrate having a structure in which a resin sheet having excellent air permeability is disposed on the surface of any one of a plurality of insulating base material layers. According to this configuration, gas generated inside the base material during the production of the multilayer substrate or the like is efficiently discharged to the outside of the base material through the resin sheet having excellent gas permeability, and therefore interlayer peeling caused by residual gas inside the base material can be suppressed.

Prior art documents

Patent document

Patent document 1: international publication No. 2018/079477

However, in the multilayer substrate disclosed in patent document 1, since the resin sheet is not an adhesive layer for bonding the insulating base material layers to each other, the bonding strength of the bonding surface (interface) between the insulating base material layer and the resin sheet is not high in many cases. Further, if the bonding strength at the bonding surface between the insulating base layer and the resin sheet is low, interlayer peeling at the bonding surface (interface) is likely to occur.

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

An object of the present invention is to provide a multilayer substrate in which interlayer peeling caused by residual gas in a base material is suppressed while securing bonding strength of bonding surfaces of insulating base material layers to each other.

Means for solving the problems

(1) The utility model discloses a multilayer substrate's characterized in that has:

a substrate which is a laminate formed by laminating a plurality of insulating substrate layers; and

a conductor pattern formed on the plurality of insulating base material layers,

at least one of the plurality of insulating substrate layers has: and an exhaust section that partially overlaps a planar conductor that is a conductor pattern having a largest area among the conductor patterns, as viewed in a direction in which the plurality of insulating base material layers are stacked, and extends from an inner side to an outer side of the planar conductor.

If a large conductor pattern (metal pattern) is present in the base material, gas generated in the base material during production or the like cannot permeate through the conductor pattern, and therefore, depending on the place where the gas is generated, the discharge path may become long, and the gas may remain in the base material. In particular, gas generated in the vicinity of the center of a planar conductor (a conductor pattern having a large area) is more likely to remain than gas generated at the edge of the planar conductor. Therefore, the conductor pattern may be deformed by the gas remaining in the base material, and desired characteristics may not be obtained. Further, if a gas remains in the base material, the gas may expand and cause interlayer peeling during heating of the multilayer substrate (during manufacturing of the multilayer substrate, during a reflow step during mounting of the multilayer substrate, during mounting of the multilayer substrate using a heat bar or the like, or during bending of the multilayer substrate accompanied by heating, or the like).

On the other hand, according to the multilayer substrate, the insulating base material layer has the exhaust portion extending from the inside to the outside of the planar conductor (the conductor pattern having the largest area) as viewed in the laminating direction. Therefore, a path for discharging the gas generated in the substrate during the production to the outside can be secured, and the gas can be efficiently discharged to the outside of the substrate, so that delamination caused by the gas remaining in the substrate can be suppressed. Further, according to the multilayer substrate, the base material can be formed without using a member having excellent air permeability (for example, a resin sheet having excellent air permeability) having weak bonding strength with the insulating base material layer, and therefore the bonding strength of the bonding surface (interface) between the insulating base material layers can be ensured.

(2) Preferably, in the above (1), the exhaust portion is a recess or a through hole having a partially reduced thickness in the stacking direction.

(3) Preferably, in the above (2), at least a part of the exhaust part is buried in an insulating base material layer other than the insulating base material layer in which the exhaust part is formed.

(4) Preferably, in any one of the above (1) to (3), the insulating base material layer is composed of a thermoplastic resin.

(5) Preferably, in any one of the above (1) to (4), two or more of the plurality of insulating base material layers have the exhaust portion, and two of the two or more insulating base material layers are disposed at positions sandwiching the planar conductor in the stacking direction.

(6) Preferably, in any one of the above (1) to (5), the insulating substrate layer to which the planar conductor is in contact has the exhaust portion.

(7) Preferably, in any one of the above (1) to (6), two or more of the plurality of insulating substrate layers have the exhaust part, and the plurality of insulating substrate layers are stacked such that the exhaust parts adjacent in the stacking direction do not overlap with each other when viewed from the stacking direction.

(8) Preferably, in any one of the above (1) to (7), the plurality of exhaust portions are formed in the same insulating base material layer, and the plurality of exhaust portions formed in the same insulating base material layer are arranged in line symmetry with respect to a straight line passing through a center of the planar conductor as viewed in the stacking direction.

(9) Preferably, in any one of the above (1) to (8), the plurality of exhaust portions are formed in the same insulating base material layer, and the plurality of exhaust portions formed in the same insulating base material layer are arranged in point symmetry with respect to the center of the planar conductor as viewed in the stacking direction.

Effect of the utility model

According to the present invention, there is provided a multilayer substrate in which interlayer peeling caused by residual gas in a base material is suppressed while securing bonding strength of bonding surfaces of insulating base material layers to each other.

Drawings

Fig. 1A is an external perspective view of the multilayer substrate 101 according to embodiment 1, and fig. 1B is an exploded perspective view of the multilayer substrate 101.

Fig. 2 is a plan view of the insulating base material layer 13a according to embodiment 1.

Fig. 3 is a sectional view sequentially showing the manufacturing process of the multilayer substrate 101.

Fig. 4A is an external perspective view of the multilayer substrate 102 according to embodiment 2, and fig. 4B is an exploded perspective view of the multilayer substrate 102.

Fig. 5 is a plan view of the insulating base material layer 13b according to embodiment 2.

Fig. 6A is an external perspective view of the multilayer substrate 103 according to embodiment 3, and fig. 6B is an exploded perspective view of the multilayer substrate 103.

Fig. 7 is a plan view of the insulating base material layer 12c according to embodiment 3.

Fig. 8 is a sectional view sequentially showing the manufacturing process of the multilayer substrate 103.

Fig. 9A is an external perspective view of the multilayer substrate 104 according to embodiment 4, and fig. 9B is an exploded perspective view of the multilayer substrate 104.

Fig. 10 is a plan view of the insulating base layer 13d according to embodiment 4.

Fig. 11 is a sectional view sequentially showing the manufacturing process of the multilayer substrate 104.

Description of the reference numerals

And (3) CP: a center of the planar conductor;

p1, P1A: an electrode;

s1: a 1 st major surface of the substrate;

s2: a 2 nd major surface of the substrate;

v1, V2, V3, V4: an interlayer connection conductor;

10A, 10B, 10C, 10D: a substrate;

11a, 11b, 11c, 11d, 12a, 12b, 12c, 12d, 13a, 13b, 13c, 13d, 14a, 14b, 14 d: an insulating substrate layer;

31. 32, 33, 34: a conductor;

101. 102, 103, 104: a multilayer substrate.

Detailed Description

Hereinafter, a plurality of modes for carrying out the present invention will be described with reference to the drawings and by way of specific examples. In the drawings, the same reference numerals are given to the same parts. The embodiments are separately shown for convenience in view of ease of explanation or understanding of the points, but partial replacement or combination of the structures shown in different embodiments can be made. In embodiment 2 and thereafter, descriptions of common matters with embodiment 1 are omitted, and only differences will be described. In particular, the same operational effects based on the same structure will not be mentioned successively in each embodiment.

EXAMPLE 1 embodiment

Fig. 1A is an external perspective view of the multilayer substrate 101 according to embodiment 1, and fig. 1B is an exploded perspective view of the multilayer substrate 101. Fig. 2 is a plan view of the insulating base material layer 13a according to embodiment 1. In fig. 2, to make the structure easy to understand, the positions where the exhaust portions NR11, NR12, NR13, and NR14 overlap when a plurality of insulating base material layers are stacked are shown by broken lines. The multilayer substrate 101 according to the present embodiment is an electronic component surface-mounted on a circuit board or the like.

The multilayer substrate 101 includes a base 10A, conductor patterns (

conductors

31, 32, 33, and 34, and an electrode P1), interlayer connection conductors V1, V2, V3, and V4. In the present embodiment, the conductor 32 having the largest area among the plurality of conductor patterns corresponds to a "planar conductor" in the present invention.

The base 10A is a rectangular parallelepiped made of resin (thermoplastic resin) having the longitudinal direction aligned with the X-axis direction, and has a 1 st main surface S1 and a 2 nd main surface S2 facing each other. The electrode P1 is formed on the 1 st main surface S1, and the

conductors

33, 34 are formed on the 2 nd main surface S2 of the substrate 10A. The

conductors

31 and 32 and the interlayer connection conductors V1 to V4 are formed inside the substrate 10A.

The substrate 10A is a laminate in which insulating

substrate layers

11a, 12a, 13a, and 14a made of resin (thermoplastic resin) are sequentially laminated. The insulating base layers 11a to 14a are each a flat plate made of the same material. The insulating base layers 11a to 14a are resin sheets mainly composed of, for example, Liquid Crystal Polymer (LCP), polyether ether ketone (PEEK), or the like.

An electrode P1 is formed on the lower surface of the insulating base material layer 11 a. The electrode P1 is a rectangular conductor pattern disposed near the 4 th corner (the lower right corner of the insulating base material layer 11a in fig. 1B) of the insulating base material layer 11 a. The electrode P1 is a conductor pattern such as Cu foil, for example. Further, an interlayer connection conductor V1 is formed on the insulating base layer 11 a.

A conductor 31 is formed on the upper surface of the insulating base material layer 12 a. The conductor 31 is a linear conductor pattern extending in the X-axis direction and disposed on the 3 rd side (the right side of the insulating base material layer 12a in fig. 1B) from the center of the insulating base material layer 12 a. The conductor 31 is a conductor pattern such as Cu foil, for example. Further, an interlayer connection conductor V2 is formed on the insulating base material layer 12 a.

Further, the insulating base material layer 12a is formed with a plurality of exhaust sections NR11, NR12, NR13, and NR 14. The two exhaust gas portions NR11 are rectangular through holes whose longitudinal direction coincides with the X-axis direction, and are arranged near the 1 st side (left side of the insulating base material layer 12a in fig. 1B) of the insulating base material layer 12 a. The two exhaust gas portions NR12 are rectangular through holes whose longitudinal direction coincides with the Y-axis direction, and are arranged near the 2 nd side of the insulating base material layer 12a (the upper side of the insulating base material layer 12a in fig. 1B). The two exhaust gas portions NR13 are rectangular through holes whose longitudinal direction coincides with the X-axis direction, and are arranged near the 3 rd side (the right side of the insulating base material layer 12a in fig. 1B) of the insulating base material layer 12 a. The two exhaust gas portions NR14 are rectangular through holes whose longitudinal direction coincides with the Y-axis direction, and are arranged near the 4 th side of the insulating base material layer 12a (the lower side of the insulating base material layer 12a in fig. 1B). The sizes of the exhaust portions NR11, NR12, NR13, and NR14 are, for example, 20 to 100 μm in width and 50 to 100 μm in height in the case of through holes.

A conductor 32 is formed on the upper surface of the insulating base layer 13 a. The conductor 32 is a substantially rectangular conductor pattern disposed near the center of the insulating base layer 13 a. The conductor 32 is a conductor pattern such as Cu foil, for example. Further, an interlayer connection conductor V3 is formed on the insulating base layer 13 a.

Conductors

33 and 34 are formed on the upper surface of the insulating base material layer 14 a. The conductor 33 is a linear conductor pattern extending in the Y-axis direction and disposed on the 1 st side (left side of the insulating base material layer 14a in fig. 1B) from the center of the insulating base material layer 14 a. The conductor 34 is an L-shaped conductor pattern disposed on the 3 rd side (the right side of the insulating base material layer 14a in fig. 1B) from the center of the insulating base material layer 14 a. The

conductors

33 and 34 are conductor patterns such as Cu foils. Further, an interlayer connection conductor V4 is formed on the insulating base material layer 14 a.

As shown in fig. 1B, the electrode P1 is connected to one end of the conductor 31 via interlayer connection conductors V1 and V2. The other end of the conductor 31 is connected to the conductor 32 via the interlayer connection conductor V3. The conductor 32 is connected to the conductor 33 via the interlayer connection conductor V4.

As shown in fig. 2, the exhaust gas portions NR11 to NR14 formed in the same insulating base material layer (12a) partially overlap the planar conductor (conductor 32) when viewed from the stacking direction (Z-axis direction) of the insulating base material layers 11a to 14 a. The exhaust portions NR11 to NR14 are formed to extend from the inside to the outside of the planar conductor when viewed in the Z-axis direction.

In the present embodiment, the exhaust gas portions NR11 to NR14 are partially provided in the same insulating base material layer 12a, and are not uneven. In the present embodiment, as shown in fig. 2, the exhaust gas portions NR11 to NR14 formed in the same insulating base layer 12a are arranged in line symmetry with respect to a straight line (for example, a straight line extending in the X axis direction) passing through the center CP of the planar conductor (conductor 32) when viewed from the Z axis direction. Further, in the present embodiment, the exhaust gas portions NR11 to NR14 formed in the same insulating base material layer 12a are arranged point-symmetrically with respect to the center CP of the planar conductor when viewed from the Z-axis direction.

The multilayer substrate 101 according to the present embodiment is manufactured by, for example, the following manufacturing method. Fig. 3 is a sectional view sequentially showing the manufacturing process of the multilayer substrate 101. In fig. 3, for convenience of explanation, a single chip (single piece) is illustrated, but the actual manufacturing process of the multilayer substrate 101 is performed in a collective substrate state. The "collective substrate" refers to a mother substrate including a plurality of multilayer substrates 101. This is the same also in the drawings showing the subsequent manufacturing steps.

First, as shown in fig. 3 (1), a plurality of insulating

base material layers

11a, 12a, 13a, and 14a made of resin (thermoplastic resin) are prepared. The insulating base layers 11a to 14a are resin sheets mainly composed of, for example, Liquid Crystal Polymer (LCP), polyether ether ketone (PEEK), or the like.

Next, a conductor pattern is formed on the plurality of insulating base material layers 11a to 14 a. Specifically, a metal foil (e.g., Cu foil) laminated to one face of the insulating base material layer is patterned by photolithography. Thus, the electrode P1 is formed on the lower surface of the insulating base material layer 11a, the conductor 32 is formed on the upper surface of the insulating base material layer 13a, and the

conductors

33 and 34 are formed on the upper surface of the insulating base material layer 14 a.

The step of forming a conductor pattern (the

conductors

32, 33, 34, etc., the electrode P1) on any one of the plurality of insulating base material layers 11a to 14a is an example of the "conductor pattern forming step" of the present invention.

Further, exhaust sections NR11, NR13, and the like are formed in the insulating base material layer 12 a. The exhaust portions NR11 and NR13 are through holes that partially overlap the planar conductor (conductor 32) when viewed in the Z-axis direction when the plurality of insulating base material layers 11a to 14a are subsequently laminated, and extend from the inside to the outside of the planar conductor. The exhaust sections NR11, NR13, and the like are formed by etching the insulating base material layer 12a with a laser or the like, for example. The exhaust portions NR11, NR13, and the like may be formed by punching or the like.

The step of forming the exhaust parts NR11, NR13, and the like on any one of the plurality of insulating base material layers 11a to 14a is an example of the "exhaust part forming step" of the present invention.

When the through hole is formed by a laser or the like, the through hole has a tapered shape, for example.

Further, an interlayer connection conductor V4 is formed on the insulating base material layer 14 a. The interlayer connection conductor V4 is provided, for example, by providing a through hole in the insulating base material layer 14a with a laser or the like, disposing a conductive paste containing Cu, Sn, an alloy thereof, or the like, and a resin material in the through hole, and then curing the conductive paste by heating and pressing. Interlayer connection conductors other than the interlayer connection conductor V4 are formed on the insulating base material layers 11a to 13a, but are not shown in fig. 3.

Next, as shown in fig. 3 (2), a plurality of insulating

base material layers

11a, 12a, 13a, and 14a are sequentially stacked.

The step of laminating the plurality of insulating base material layers 11a to 14a after the conductor pattern forming step and the exhaust portion forming step is an example of the "laminating step" of the present invention.

Then, the laminated plurality of insulating base material layers 11a to 14a are heated and pressed (collectively pressed) to form a multilayer substrate 101 (base material 10A) shown in fig. 3 (3). At the time of heating and pressing, in the exhaust portions NR11, NR13, and the like, the insulating base material layer (resin material) flows (see an arrow shown in (2) in fig. 3). Thereby, the exhaust sections NR11, NR13, and the like are buried.

The step of forming the base material 10A by heating and pressing the plurality of insulating base material layers 11a to 14a laminated after the laminating step is an example of the "heating and pressing step" of the present invention.

In the present embodiment, since the insulating base material layers 11a to 14a and the interlayer connection conductors V1 to V4 are made of resin, when they are subjected to heat of a predetermined temperature or higher, a part of them is thermally decomposed to generate CO₂Such as gases and moisture. When such gas and moisture remain in the laminate, the gas (the gas and the gas generated from the moisture) expands during heating of the multilayer substrate (during manufacturing of the multilayer substrate, during a reflow step during mounting of the multilayer substrate, during mounting of the multilayer substrate using a heat bar or the like, or during bending of the multilayer substrate accompanied by heating), and thus delamination (delamination) and poor bonding between the interlayer connection conductor and another conductor accompanied by the delamination are likely to occur. Therefore, it is important to discharge the gas to the outside of the substrate during the production of the multilayer substrate.

However, if a large conductor pattern (metal pattern) is present in the base material, the conductor pattern is not permeable to gas generated in the base material during production or the like, and therefore, depending on the place where the gas is generated, the discharge path may become long, and the gas may remain in the base material. In particular, gas generated in the vicinity of the center of a planar conductor (a conductor pattern having a large area) is more likely to remain than gas generated at the edge of the planar conductor. Therefore, the conductor pattern may be deformed by the gas remaining in the base material, and desired characteristics may not be obtained. Further, if a gas remains in the base material, the gas may expand and cause interlayer peeling during heating of the multilayer substrate (during manufacturing of the multilayer substrate, during a reflow step during mounting of the multilayer substrate, during mounting of the multilayer substrate using a heat bar or the like, or during bending of the multilayer substrate accompanied by heating, or the like).

On the other hand, according to the above manufacturing method, the exhaust portions NR11 to NR14 are formed in the insulating base material layer 12a, and the exhaust portions NR11 to NR14 extend from the inside to the outside of the planar conductor (conductor 32) when viewed from the Z-axis direction. Therefore, a path for discharging the gas generated in the substrate 10A during the manufacturing process to the outside can be secured, and the gas can be efficiently discharged to the outside of the substrate, so that delamination caused by the gas remaining in the substrate 10A can be suppressed.

Further, according to the above-described manufacturing method, the base material 10A can be formed without using a member having excellent air permeability (for example, a resin sheet having excellent air permeability) having weak bonding strength with the insulating base material layer, and therefore, the bonding strength of the bonding surface (interface) between the insulating base material layers can be ensured. Specifically, the base material 10A according to the present embodiment is a base material in which a plurality of insulating base material layers 11a to 14a made of the same material are heated and pressed (collectively pressed) and the surfaces thereof are welded to each other. Therefore, the bonding surface of the different materials does not exist on the bonding surface of the insulating base material layers 11a to 14a, and interlayer peeling due to a difference in physical properties between the different materials can be suppressed.

Further, according to the above manufacturing method, the exhaust parts NR11 to NR14 are partially provided in the same insulating base material layer 12a, and are not uneven. This can suppress deformation (deflection or the like) during transport or lamination of the insulating base material layer 12a on which the exhaust gas sections NR11 to NR14 are formed. In addition, according to the above manufacturing method, since the surrounding insulating base material layer flows to fill the exhaust portions NR11 to NR14 during the heating and pressing, the substrate 10A having a flat surface (the 1 st main surface S1 or the 2 nd main surface S2) can be easily formed.

In the present embodiment, since the plurality of insulating base material layers 11a to 14a are made of thermoplastic resin, the insulating base material layers (resin material) easily flow during heating and pressing, and the exhaust portions NR11 to NR14 are easily buried after the substrate 10A is formed. Therefore, the substrate 10A having a flat surface (the 1 st main surface S1 or the 2 nd main surface S2) can be easily formed. Further, since the substrate 10A can be easily formed by heating and pressing (collectively pressing) the plurality of insulating base material layers 11a to 14a made of thermoplastic resin, the number of manufacturing steps of the substrate 10A can be reduced, and the cost can be reduced. Further, according to the above-described manufacturing method, a multilayer substrate which can be easily plastically deformed and can maintain (hold) a desired shape can be obtained.

In the present embodiment, the plurality of exhaust gas sections NR11 to NR14 are formed on the same insulating base material layer 12a so as to be arranged in line symmetry with respect to a straight line passing through the center CP of the planar conductor (conductor 32) when viewed in the Z-axis direction when the plurality of insulating base material layers 11a to 14a are stacked. This reduces the deviation of the distribution of the exhaust portions NR11 to NR14 with respect to the planar conductor, and facilitates the uniformity of the exhaust effect in the planar direction. That is, the gas does not locally remain, and the effect of suppressing interlayer peeling is improved. Further, according to the above-described manufacturing method, since the non-uniformity of the flow of the insulating base material layer from the inside to the outside of the planar conductor as viewed from the Z-axis direction can be suppressed at the time of heating and pressing, the generation of the unevenness on the surface of the substrate 10A and the deformation of the conductor pattern (the conductors 31 to 34 or the electrode P1) accompanying the irregular flow of the insulating base material layer at the time of heating and pressing can be suppressed.

Further, in the present embodiment, the plurality of exhaust gas portions NR11 to NR14 are formed in the same insulating base material layer 12a so as to be disposed in point symmetry with respect to the center CP of the planar conductor (conductor 32) when viewed from the Z-axis direction when the plurality of insulating base material layers 11a to 14a are stacked. This can suppress local gas remaining, and further improve the effect of suppressing interlayer peeling. In addition, according to the above-described manufacturing method, the occurrence of irregularities on the surface of the substrate 10A and the deformation of the conductor pattern (the conductors 31 to 34 or the electrode P1) due to the irregular flow of the insulating base material layer during heating and pressing can be further suppressed.

EXAMPLE 2 EXAMPLE

In embodiment 2, an example is shown in which the exhaust unit is a through hole group composed of a plurality of small through holes.

Fig. 4A is an external perspective view of the multilayer substrate 102 according to embodiment 2, and fig. 4B is an exploded perspective view of the multilayer substrate 102. Fig. 5 is a plan view of the insulating base material layer 13b according to embodiment 2. In fig. 5, to make the structure easier to understand, the positions where the exhaust sections NR11A, NR12A, NR13A, and NR14A overlap when a plurality of insulating base material layers are stacked are shown by broken lines.

The multilayer substrate 102 is different from the multilayer substrate 101 according to embodiment 1 in that it includes a base material 10B. The other structure of the multilayer substrate 102 is the same as that of the multilayer substrate 101.

Hereinafter, a description will be given of a portion different from the multilayer substrate 101 according to embodiment 1.

The substrate 10B is a laminate in which a plurality of insulating substrate layers 11B, 12B, 13B, and 14B are sequentially laminated. The insulating base material layer 12b is different from the insulating base material layer 12a described in embodiment 1 in that a plurality of exhaust sections NR11A, NR12A, NR13A, and NR14A are formed. The materials and the outer shapes of the insulating base layers 11b to 14b are the same as those of the insulating base layers 11a to 14a described in embodiment 1.

The two exhaust sections NR11A are a through hole group in which four small rectangular through holes are arranged in the X axis direction, and are arranged near the 1 st side (the left side of the insulating base material layer 12B in fig. 4B) of the insulating base material layer 12B. The two exhaust parts NR12A are a through hole group in which three small rectangular through holes are arranged in the Y axis direction, and are arranged in the vicinity of the 2 nd side of the insulating base material layer 12B (the upper side of the insulating base material layer 12B in fig. 4B). The two exhaust sections NR13A are a through hole group in which four small rectangular through holes are arranged in the X axis direction, and are arranged near the 3 rd side (the left side of the insulating base material layer 12B in fig. 4B) of the insulating base material layer 12B. The two exhaust sections NR14A are a through hole group in which three small rectangular through holes are arranged in the Y axis direction, and are arranged near the 4 th side of the insulating base material layer 12B (the lower side of the insulating base material layer 12B in fig. 4B).

As shown in fig. 5, the exhaust gas portions NR11A to NR14A formed in the same insulating base material layer (12a) partially overlap the planar conductor (conductor 32) when viewed in the Z-axis direction. The exhaust portions NR11A to NR14A are formed to extend from the inside to the outside of the planar conductor when viewed in the Z-axis direction.

In this manner, the exhaust unit may be a hole group in which a plurality of small holes are arranged. In addition, when the exhaust unit is a hole group, it is preferable that the gaps between the plurality of small holes are short. The gap (D1) between the plurality of small holes in the exhaust section (hole group) is preferably shorter than the thickness (T1) in the lamination direction of the insulating base material layer in which the exhaust section is formed (D1 < T1), for example.

In the case where the exhaust portion is a large hole, even if the insulating base material layer flows during heating and pressing, the exhaust portion is difficult to be buried, and it is difficult to ensure flatness of the surface of the base material. Further, in the case where the vent portion is a large hole, the amount of flow of the insulating base material layer during heating and pressing also increases, and therefore deformation and positional displacement of the conductor pattern due to the flow of the insulating base material layer are likely to occur. On the other hand, since the exhaust sections NR11A to NR14A according to the present embodiment are hole groups in which a plurality of small holes are arranged, the through hole groups are easily filled by the flow of the insulating base material layer during heating and pressing, and the flatness of the surface of the substrate 10B is easily ensured. Further, according to the above-described manufacturing method, the amount of flow of the insulating base material layer is also reduced during heating and pressing, and deformation of the conductor pattern and the like associated with the flow of the insulating base material layer can be suppressed.

EXAMPLE 3

In embodiment 3, an example is shown in which the exhaust part is in contact with the planar conductor.

Fig. 6A is an external perspective view of the multilayer substrate 103 according to embodiment 3, and fig. 6B is an exploded perspective view of the multilayer substrate 103. Fig. 7 is a plan view of the insulating base material layer 12c according to embodiment 3. In fig. 7, to make the structure easy to understand, the positions where the exhaust portions NR11, NR12, NR13, and NR14 overlap when a plurality of insulating base material layers are stacked are shown by broken lines.

The multilayer substrate 103 is different from the multilayer substrate 101 according to embodiment 1 in that it includes a base material 10C. The other structures of the multilayer substrate 103 are substantially the same as those of the multilayer substrate 101.

The substrate 10C is a laminate in which a plurality of insulating substrate layers 11C, 12C, and 13C are sequentially laminated. The materials and the outer shapes of the insulating base layers 11c to 13c are the same as those of the insulating base layers 11a to 13c described in embodiment 1.

An electrode P1A is formed on the lower surface of the insulating base layer 11 c. The electrode P1A is a rectangular conductor pattern disposed on the 3 rd side (the right side of the insulating base material layer 11c in fig. 6B) of the center of the insulating base material layer 11 c. The electrode P1A is a conductor pattern such as Cu foil, for example. Further, an interlayer connection conductor V1 is formed on the insulating base layer 11 c.

A conductor 31 is formed on the upper surface of the insulating base material layer 12 c. The conductor 31 is the same as the conductor 31 described in embodiment 1. Further, an interlayer connection conductor V2 is formed on the insulating base material layer 12 c.

Further, the insulating base material layer 12c is formed with a plurality of exhaust sections NR11, NR12, NR13, and NR 14. The exhaust sections NR11 to NR14 are the same as the exhaust sections NR11 to NR14 described in embodiment 1.

Conductors

33 and 34 are formed on the upper surface of the insulating base layer 13 c. The

conductors

33 and 34 are the same as the

conductors

33 and 34 described in embodiment 1. Further, an interlayer connection conductor V3 is formed on the insulating base layer 13 c.

As shown in fig. 6B, the electrode P1A is connected to the conductor 32 via interlayer connection conductors V1 and V2. The conductor 32 is connected to the conductor 33 via the interlayer connection conductor V3.

In the present embodiment, the exhaust sections NR11 to NR14 are formed in the insulating base material layer 12c on which the planar conductor (conductor 32) is formed.

The multilayer substrate 103 according to the present embodiment is manufactured by, for example, the following manufacturing method. Fig. 8 is a sectional view sequentially showing the manufacturing process of the multilayer substrate 103.

First, as shown in fig. 8 (1), a plurality of insulating

base material layers

11c, 12c, and 13c are prepared. Next, a conductor pattern is formed on the plurality of insulating base material layers 11c to 13 c. Specifically, the electrode P1A is formed on the lower surface of the insulating base material layer 11c, the conductor 32 is formed on the upper surface of the insulating base material layer 12c, and the

conductors

33 and 34 are formed on the upper surface of the insulating base material layer 13 c.

The step of forming the conductor pattern (the

conductors

32, 33, 34, the electrode P1A) on any one of the plurality of insulating base material layers 11c to 13c is an example of the "conductor pattern forming step" of the present invention.

Further, exhaust sections NR11, NR13, and the like are formed in the insulating base material layer 12 c. Further, an interlayer connection conductor V3 is formed on the insulating base layer 13 c.

The subsequent step of forming the exhaust parts NR11, NR13, and the like on the insulating base material layer 12c in contact with the planar conductor (conductor 32) in the laminating step (when a plurality of insulating base material layers 11c to 13c are laminated) is an example of the "exhaust part forming step" of the present invention.

Next, as shown in fig. 8 (2), a plurality of insulating

base material layers

11c, 12c, and 13c are sequentially stacked.

The step of laminating the plurality of insulating base material layers 11c to 13c after the conductor pattern forming step and the exhaust section forming step is an example of the "laminating step" of the present invention.

Then, the plurality of laminated insulating base material layers 11C to 13C are heated and pressed (collectively pressed) to form a multilayer substrate 103 (base material 10C) shown in (3) in fig. 8. At the time of heat pressing, the insulating base material layer (resin material) flows into the exhaust sections NR11, NR13, and the like (refer to an arrow shown in (2) in fig. 8). Thereby, the exhaust sections NR11, NR13, and the like are buried.

The step of forming the base material 10C by heating and pressing the plurality of insulating base material layers 11C to 13C stacked after the stacking step is an example of the "heating and pressing step" of the present invention.

In the present embodiment, the exhaust sections NR11 to NR14 are formed in the insulating base material layer 12c where the planar conductor (conductor 32) contacts when the plurality of insulating base material layers 11c to 13c are stacked in the stacking step. According to the above manufacturing method, the gas generated in the vicinity of the planar conductor during the manufacturing of the substrate 10A is quickly discharged to the outside without being blocked by the planar conductor. Therefore, the amount of gas remaining in the substrate 10A can be reduced, and interlayer peeling during heating during production or use can be suppressed.

In the present embodiment, the exhaust portions NR11 to NR14 are formed in the insulating base material layer 12c on which the planar conductor (conductor 32) is formed, but the present invention is not limited to this. For example, even when the insulating base material layer 13c in contact with the planar conductor forms the exhaust portion when the plurality of insulating base material layers 11c to 13c are stacked, the same effect can be obtained.

EXAMPLE 4 embodiment

In embodiment 4, an example of a multilayer substrate in which exhaust portions are formed in two or more insulating base material layers is shown.

Fig. 9A is an external perspective view of the multilayer substrate 104 according to embodiment 4, and fig. 9B is an exploded perspective view of the multilayer substrate 104. Fig. 10 is a plan view of the insulating base layer 13d according to embodiment 4. In fig. 10, to make the structure easy to understand, positions where the exhaust portions NR11, NR12, NR13, NR14, NR21, NR22, NR23, and NR24 overlap when a plurality of insulating base material layers are stacked are shown by broken lines. Further, fig. 10 shows exhaust portions NR21 to NR23 in a dot pattern.

The multilayer substrate 104 is different from the multilayer substrate 101 according to embodiment 1 in that it includes a base material 10D. The multilayer substrate 104 is different from the multilayer substrate 101 in that the

conductors

33 and 34 are formed inside the base 10D. The other structure of the multilayer substrate 104 is substantially the same as that of the multilayer substrate 101.

The substrate 10D is a laminate in which a plurality of insulating substrate layers 11D, 12D, 13D, and 14D are sequentially laminated. The structures of the insulating substrate layers 11d to 14d are substantially the same as those described in embodiment 1.

An electrode P1A is formed on the lower surface of the insulating base layer 11 d. The electrode P1A is a rectangular conductor pattern disposed on the 3 rd side (the right side of the insulating base material layer 11d in fig. 9B) of the center of the insulating base material layer 11 d. Further, an interlayer connection conductor V1 is formed on the insulating base layer 11 d.

A conductor 32 is formed on the upper surface of the insulating base layer 12 d. The conductor 32 is the same as the conductor 32 described in embodiment 1. Further, an interlayer connection conductor V2 is formed on the insulating base layer 12 d.

Further, the insulating base layer 12d is formed with a plurality of exhaust sections NR11, NR12, NR13, and NR 14. The exhaust sections NR11 to NR14 are the same as the exhaust sections NR11 to NR14 described in embodiment 1.

Conductors

33 and 34 are formed on the upper surface of the insulating base layer 13 d. The

conductors

33 and 34 are the same as the

conductors

33 and 34 described in embodiment 1. Further, an interlayer connection conductor V3 is formed on the insulating base layer 13 d.

Further, the insulating base layer 13d has exhaust sections NR21, NR22, NR23, and NR 24. The exhaust portion NR21 is a rectangular through hole whose longitudinal direction coincides with the X-axis direction, and is disposed near the center of the 1 st side (the left side of the insulating base material layer 13d in fig. 9B) of the insulating base material layer 13 d. The exhaust portion NR22 is a rectangular through hole whose longitudinal direction coincides with the Y-axis direction, and is disposed near the center of the 2 nd side (the upper side of the insulating base material layer 13d in fig. 9B) of the insulating base material layer 13 d. The exhaust portion NR23 is a rectangular through hole whose longitudinal direction coincides with the X-axis direction, and is disposed near the center of the 3 rd side (the right side of the insulating base layer 13d in fig. 9B) of the insulating base layer 13 d. The exhaust portion NR24 is a rectangular through hole whose longitudinal direction coincides with the Y-axis direction, and is disposed near the center of the 4 th side (the lower side of the insulating base material layer 13d in fig. 9B) of the insulating base material layer 13 d.

As shown in fig. 9B, the electrode P1A is connected to the conductor 32 via interlayer connection conductors V1 and V2. The conductor 32 is connected to the conductor 33 via the interlayer connection conductor V3.

In the present embodiment, the exhaust portions NR11 to NR14 and NR21 to NR24 are formed in the pair of insulating base material layers 12d and 13d disposed at positions sandwiching the planar conductor (conductor 32) in the Z-axis direction, respectively. In the present embodiment, as shown in fig. 9B and 10, the exhaust portions NR11 to NR14 and NR21 to NR24 adjacent to each other in the Z-axis direction do not overlap with each other when viewed from the Z-axis direction.

The multilayer substrate 104 according to the present embodiment is manufactured by, for example, the following manufacturing method. Fig. 11 is a sectional view sequentially showing the manufacturing process of the multilayer substrate 104.

First, as shown in fig. 11 (1), a plurality of insulating

base material layers

11d, 12d, 13d, and 14d are prepared. Next, a conductor pattern is formed on the insulating

base material layers

11d, 12d, and 13 d. Specifically, the electrode P1A is formed on the lower surface of the insulating base layer 11d, the conductor 32 is formed on the upper surface of the insulating base layer 12d, and the

conductors

33 and 34 are formed on the upper surface of the insulating base layer 13 d.

The step of forming the conductor pattern (the

conductors

32, 33, 34, the electrode P1A) on any one of the plurality of insulating base material layers 11d to 14d is an example of the "conductor pattern forming step" of the present invention.

Two exhaust sections NR14 and the like are formed in the insulating base layer 12d, and an exhaust section NR24 and the like are formed in the insulating base layer 13 d. The insulating base material layers 12d and 13d are insulating base material layers disposed at positions sandwiching the planar conductor (conductor 32) in the Z-axis direction when the plurality of insulating base material layers 11d to 14d are stacked. Further, an interlayer connection conductor V3 is formed on the insulating base layer 13 d.

The step of forming the exhaust portions NR14, NR24 and the like in the pair of insulating

base material layers

12d, 13d arranged at positions sandwiching the planar conductor (conductor 32) in the Z-axis direction when the plurality of insulating base material layers 11d to 14d are laminated is an example of the "exhaust portion forming step" of the present invention.

Next, as shown in fig. 11 (2), a plurality of insulating

base material layers

11d, 12d, 13d, and 14d are sequentially stacked. At this time, the plurality of insulating base material layers 11d to 14d are stacked such that, when viewed in the Z-axis direction, a plurality of exhaust sections (an exhaust section NR14 or the like and an exhaust section NR24 or the like) adjacent in the Z-axis direction do not overlap each other.

The step of laminating the plurality of insulating base material layers 11d to 14d so that the exhaust portions NR14 and NR24 adjacent to each other in the Z-axis direction do not overlap each other when viewed from the Z-axis direction is an example of the "laminating step" of the present invention.

Then, the plurality of laminated insulating base material layers 11D to 14D are heated and pressed (collectively pressed) to form a multilayer substrate 104 (base material 10D) shown in fig. 11 (3). At the time of heat pressing, the insulating base material layer (resin material) flows into the exhaust sections NR14, NR24, and the like (refer to an arrow shown in (2) in fig. 11). Thereby, the exhaust sections NR14, NR24, and the like are buried.

The step of forming the substrate 10D by heating and pressing the plurality of insulating base material layers 11D to 14D stacked after the stacking step is an example of the "heating and pressing step" of the present invention.

In the present embodiment, when a plurality of insulating base material layers 11d to 14d are stacked, exhaust sections NR14, NR24, and the like are formed in a pair of insulating base material layers 12d and 13d arranged at positions sandwiching the planar conductor (conductor 32) in the Z-axis direction, respectively. According to this manufacturing method, the gas can be efficiently discharged from both sides of the planar conductor in the Z-axis direction.

In the present embodiment, the plurality of insulating base material layers 11d to 14d are stacked such that the exhaust sections NR14 and NR24 adjacent to each other in the Z-axis direction do not overlap each other when viewed from the Z-axis direction. Therefore, as compared with the case where the exhaust portions adjacent in the Z-axis direction overlap each other, the flatness of the main surface (the 1 st main surface S1 or the 2 nd main surface S2) of the substrate 10D can be ensured.

Other embodiments

In the above-described embodiments, the multilayer substrate is surface-mounted on an electronic component such as a circuit board, but the multilayer substrate of the present invention is not limited to this. The multilayer substrate of the present invention may be a cable connecting two circuit substrates to each other or a cable connecting between a circuit substrate and another component. Further, a connector may be provided on the multilayer substrate as necessary.

In the embodiments described above, the substrate is a rectangular parallelepiped of thermoplastic resin, but the shape of the substrate is not limited to this. The planar shape of the substrate may be, for example, a polygon, a circle, an ellipse, an L-shape, a T-shape, a Y-shape, a crank shape, or the like. The substrate may be made of a thermosetting resin. The substrate may be a dielectric ceramic such as low temperature co-fired ceramic (LTCC). The substrate is not limited to being formed by heating and pressing a plurality of insulating base material layers made of the same material, and may have an adhesive layer (a layer having a higher bonding strength with one insulating base material layer than with another insulating base material layer). When the substrate has an adhesive layer (insulating substrate layer), the exhaust section may be formed in the adhesive layer. When the substrate has an adhesive layer, the substrate may be a composite laminate of a plurality of resins. For example, the substrate may be a laminate of a thermosetting resin sheet such as a glass/epoxy plate and a thermoplastic resin sheet.

In the above-described embodiments, examples of the substrate in which three or four insulating base material layers are laminated are shown, but the number of the insulating base material layers to be laminated is not limited to this. The number of insulating base material layers forming the base material can be changed as appropriate. In addition, in the multilayer substrate, a protective layer such as a solder resist may be formed on the 1 st main surface S1 or the 2 nd main surface S2.

In the above-described embodiments, the through hole (or the plurality of small through holes) in which the exhaust portion is rectangular is illustrated as an example, but the exhaust portion of the present invention is not limited to this. The exhaust portion may be, for example, a recess (or a plurality of small recess groups) having a partially reduced thickness in the Z-axis direction.

The circuit structure formed on the multilayer substrate is not limited to the structure of each of the embodiments described above, and can be appropriately modified within the range that achieves the operation and effect of the present invention. The circuit formed on the multilayer substrate may be formed with, for example, a coil formed of a conductor pattern, an inductor, a capacitor formed of a conductor pattern, a frequency filter such as various filters (a low-pass filter, a high-pass filter, a band-pass filter, or a band-stop filter). Further, various other transmission lines (microstrip lines, coplanar lines, etc.) may be formed on the resin multilayer substrate, for example. Further, various electronic components such as chip components may be mounted or embedded on the resin multilayer substrate.

In the above embodiments, the conductive paste is disposed in the through hole formed in the insulating base material layer and the interlayer connection conductor is provided by curing the conductive paste by subsequent heating and pressing, but the interlayer connection conductor of the present invention is not limited to this. The interlayer connection conductor may be a conductor formed of, for example, a via plating layer or the like filled in the through hole formed in the insulating base material layer, and a conductive bonding material provided on the surface of the via plating layer or the like.

In the above-described embodiments, the example of the multilayer substrate in which the rectangular electrodes are formed on the 1 st main surface S1 of the base material is shown, but the present invention is not limited to this configuration. The shape, number, arrangement, and the like of the electrodes can be changed as appropriate. The planar shape of the electrode may be, for example, a polygon, a circle, an ellipse, an arc, a ring, an L-shape, a U-shape, a T-shape, a Y-shape, a crank-shape, or the like. The electrodes may be provided only on the 2 nd main surface S2, or may be provided on both the 1 st main surface S1 and the 2 nd main surface S2.

Finally, the above description of the embodiments is illustrative in all respects and not restrictive. It is obvious to those skilled in the art that the modifications and variations can be appropriately made. The scope of the present invention is shown not by the above-described embodiments but by the claims. Further, the scope of the present invention includes modifications from the embodiments within the equivalent scope of the claims.

Claims

1. A multilayer substrate, comprising:

a conductor pattern formed on the plurality of insulating base material layers,

2. The multilayer substrate of claim 1,

the exhaust portion is a recess or a through hole having a partially reduced thickness in the stacking direction.

3. The multilayer substrate of claim 2,

at least a part of the exhaust section is embedded in an insulating base material layer other than the insulating base material layer in which the exhaust section is formed.

4. The multilayer substrate according to any one of claims 1 to 3,

the insulating base material layer is made of thermoplastic resin.

5. The multilayer substrate according to any one of claims 1 to 3,

two or more of the plurality of insulating base material layers have the exhaust part,

two of the two or more insulating base material layers are disposed at positions sandwiching the planar conductor in the stacking direction.

6. The multilayer substrate according to any one of claims 1 to 3,

the insulating base material layer to which the planar conductor is connected has the exhaust portion.

7. The multilayer substrate according to any one of claims 1 to 3,

the plurality of insulating base material layers are laminated such that the exhaust gas portions adjacent to each other in the lamination direction do not overlap each other when viewed from the lamination direction.

8. The multilayer substrate according to any one of claims 1 to 3,

the plurality of exhaust portions are formed in the same insulating base material layer, and the plurality of exhaust portions formed in the same insulating base material layer are arranged in line symmetry with respect to a straight line passing through the center of the planar conductor as viewed in the stacking direction.

9. The multilayer substrate according to any one of claims 1 to 3,

the plurality of exhaust portions are formed in the same insulating base material layer, and the plurality of exhaust portions formed in the same insulating base material layer are arranged point-symmetrically with respect to the center of the planar conductor as viewed in the stacking direction.