JP2024031783A - Multilayer substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer substrate capable of suppressing occurrence of characteristics impedance mismatch in a section between a signal conductor layer and a radiation conductor layer.

SOLUTION: The maximum width of a second connection section A12 in a widthwise direction is smaller than that of a first connection section A11. A first intermediate section A21 includes a first heavy-line section A21b having a width in a line width direction larger than that of a rail track section A31. A second intermediate section A22 includes a second heavy-line section A22b having a width in a line width direction larger than that of the rail track section A31. The first heavy-line section A21b and the second heavy-line section A22b are adjacent to the rail track section A31.

SELECTED DRAWING: Figure 3

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a multilayer substrate including a radiation conductor layer.

As an invention related to a conventional multilayer board, an antenna module described in Patent Document 1 is known. The antenna module includes an antenna package and a connection member. The connecting member is a flexible strip-shaped substrate. The connection member includes a power supply line. The antenna package is fixed on the connecting member. The antenna package includes a patch antenna. The patch antenna is electrically connected to the feed line.

US Patent Application Publication No. 2020/0194893

By the way, in the antenna module described in Patent Document 1, a mismatch in characteristic impedance may occur in the section between the patch antenna and the feed line.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a multilayer substrate that can suppress the occurrence of characteristic impedance mismatch in the section between the signal conductor layer and the radiation conductor layer.

A multilayer substrate according to one embodiment of the present invention includes:
A laminate having a structure in which a plurality of insulator layers including an intermediate insulator layer and a negative adjacent insulator layer are stacked in alignment in the Z-axis direction, each of the plurality of insulator layers having a positive main surface. , and has a negative main surface located on the negative side of the Z-axis from the positive main surface, and the negative side adjacent insulator layer is located on the negative side of the Z-axis of the intermediate insulator layer, and a laminate that is in contact with the intermediate insulator layer;
a radiation conductor layer provided in the laminate and located on the positive side of the Z axis from the intermediate insulator layer;
a signal conductor layer provided in the laminate and located on the negative side of the Z axis from the intermediate insulator layer;
provided in the laminate, located on the negative main surface of the intermediate insulator layer, and including a first connection section, a second connection section, a line section, a first intermediate section, and a second intermediate section. the first intermediate section is adjacent to the first connection section, the second intermediate section is adjacent to the second connection section, and the line section is a connecting conductor layer adjacent to the first intermediate section and the second intermediate section;
provided in the laminate, located on the negative side of the Z-axis relative to the connection conductor layer and the signal conductor layer, and viewed in the Z-axis direction, at least a portion of the connection conductor layer and the a first ground conductor layer overlapping at least a portion of the signal conductor layer;
a first interlayer connection conductor in contact with the first connection section;
a second interlayer connection conductor in contact with the second connection section;
It is equipped with
One of the first interlayer connection conductor and the second interlayer connection conductor penetrates the intermediate insulator layer in the Z-axis direction and electrically connects the radiation conductor layer and the connection conductor layer. Ori,
The other of the first interlayer connection conductor and the second interlayer connection conductor penetrates the negative adjacent insulator layer in the Z-axis direction and electrically connects the signal conductor layer and the connection conductor layer. and
The direction in which the connecting conductor layer extends is defined as the stretching direction,
A direction perpendicular to the stretching direction and the Z-axis direction is defined as the line width direction,
The first connection section is located at a first end of the connection conductor layer in the stretching direction, and the second connection section is located at a second end of the connection conductor layer in the stretching direction, In the stretching direction, the second end of the connection conductor layer is located on the opposite side of the first end of the connection conductor layer,
In the stretching direction, both ends of the first connection section are located at equal distances from the center of the first interlayer connection conductor as viewed in the Z-axis direction,
In the stretching direction, both ends of the second connection section are located at equal distances from the center of the second interlayer connection conductor as seen in the Z-axis direction,
The maximum width of the second connection section in the line width direction is smaller than the maximum width of the first connection section in the line width direction,
The first intermediate section includes a first thick line section having a width in the line width direction that is larger than the width in the line width direction of the line section,
The second intermediate section includes a second thick line section having a width in the line width direction that is larger than the width in the line width direction of the line section,
The first thick line section and the second thick line section are adjacent to the line section.

According to the multilayer substrate according to the present invention, it is possible to suppress the occurrence of characteristic impedance mismatch in the section between the signal conductor layer and the radiation conductor layer.

FIG. 1 is an exploded perspective view of the multilayer substrate 10. FIG. 2 is a cross-sectional view of the multilayer substrate 10 taken along line AA in FIG. FIG. 3 is a top view of the connection conductor layer 24. FIG. 4 is a Smith chart. FIG. 5 is a top view of the connection conductor layer 24a. FIG. 6 is a top view of the connection conductor layer 24b. FIG. 7 is a top view of the connection conductor layer 24c. FIG. 8 is a Smith chart. FIG. 9 is a top view of the connection conductor layer 24d. FIG. 10 is a cross-sectional view of the multilayer substrate 10a. FIG. 11 is a cross-sectional view of the multilayer substrate 10b. FIG. 12 is a top view of the connection conductor layer 24 provided on the multilayer substrate 10b.

(First embodiment)
[Structure of multilayer substrate 10]
Below, the structure of the multilayer substrate 10 according to the first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view of the multilayer substrate 10. FIG. 2 is a cross-sectional view of the multilayer substrate 10 taken along line AA in FIG. FIG. 3 is a top view of the connection conductor layer 24.

Hereinafter, the stacking direction of the stacked body 12 of the multilayer substrate 10 will be defined as the vertical direction. The up-down direction coincides with the Z-axis direction. The upward direction is the positive direction of the Z axis. The downward direction is the negative direction of the Z axis. When looking at the multilayer substrate 10 in the vertical direction, the two directions in which the sides of the multilayer substrate 10 extend are defined as the left-right direction and the front-back direction, respectively. The left-right direction coincides with the X-axis direction. The front-back direction coincides with the Y-axis direction. The left-right direction is perpendicular to the up-down direction. The front-rear direction is orthogonal to the up-down direction and the left-right direction. Note that the definition of direction in this specification is an example. Therefore, the direction in which the multilayer substrate 10 is actually used does not need to match the direction in this specification. Further, the vertical direction may be reversed in each drawing. Similarly, the left and right directions may be reversed in each drawing. The front and rear directions may be reversed in each drawing.

In the following, X is a component or member of the multilayer substrate 10. In this specification, unless otherwise specified, each part of X is defined as follows. The front part of the X means the front half of the X. The rear part of the X means the rear half of the X. The left part of X means the left half of X. The right side of X means the right half of X. The upper part of X means the upper half of X. The lower part of X means the lower half of X. The front end of X means the front end of X. The rear end of X means the end of X in the rear direction. The left end of X means the left end of X. The right end of X means the right end of X. The upper end of X means the upper end of X. The lower end of X means the lower end of X. The front end of X means the front end of X and its vicinity. The rear end of X means the rear end of X and its vicinity. The left end of X means the left end of X and its vicinity. The right end of X means the right end of X and its vicinity. The upper end of X means the upper end of X and its vicinity. The lower end of X means the lower end of X and its vicinity.

The multilayer substrate 10 is used, for example, in electronic devices such as mobile phones. As shown in FIG. 1, the multilayer board 10 includes a laminate 12, a second ground conductor layer 18, a radiation conductor layer 20, connection conductor layers 22a, 22b, 24, a signal conductor layer 26, a first ground conductor layer 28, and an interlayer. It is provided with connection conductors v1 to v4.

The laminate 12 has a plate shape. The laminate 12 has a structure in which insulator layers 14a to 14g and protective layers 15a to 15c are stacked in the Z-axis direction. The insulator layers 14a to 14d and the protective layer 15a have a rectangular shape when viewed in the vertical direction. The insulator layers 14e to 14g and the protective layers 15b and 15c have a band shape extending in the horizontal direction when viewed in the vertical direction. The protective layer 15a, the insulator layers 14a to 14f, and the protective layer 15b are arranged in this order from top to bottom. The insulator layers 14e, 14f and the protective layer 15b extend rightward from the insulator layers 14a to 14d when viewed in the vertical direction.

The insulator layer 14g is laminated on the insulator layer 14e. The insulator layer 14g is located to the right of the insulator layer 14d. However, the insulator layer 14g is not in contact with the insulator layer 14d. The protective layer 15c is laminated on the insulator layer 14g.

Each of the insulating layers 14a to 14g and the protective layers 15a to 15c as described above is located on the upper main surface (positive main surface) and below the upper main surface (positive main surface) (on the negative side of the Z axis). It has a lower principal surface (negative principal surface). Further, the insulator layers 14a to 14g include an insulator layer 14d that is an intermediate insulator layer and an insulator layer 14e that is an adjacent negative insulator layer. The insulator layer 14e, which is the negative side adjacent insulator layer, is located below the insulator layer 14d, which is the intermediate insulator layer (on the negative side of the Z axis), and is located below the insulator layer 14d, which is the intermediate insulator layer. are in contact.

The material of the insulator layers 14a to 14g is a thermoplastic resin such as polyimide or liquid crystal polymer. The protective layers 15a to 15c are insulating films coated on the upper or lower main surface of the insulating layer. Each of the protective layers 15a to 15c protects the radiation conductor layer 20, the first ground conductor layer 28, and the second ground conductor layer 18. The laminate 12 as described above has flexibility.

Here, as shown in FIG. 2, the laminate 12 has a first section A1, a second section A2, and a third section A3 arranged in this order in the left-right direction (X-axis direction perpendicular to the Z-axis direction). There is. The first section A1, the second section A2, and the third section A3 are arranged in this order from left to right. The thickness of the first section A1 in the vertical direction (Z-axis direction) is larger than the thickness of the second section A2 in the vertical direction (Z-axis direction). The thickness of the third section A3 in the vertical direction (Z-axis direction) is larger than the thickness of the second section A2 in the vertical direction (Z-axis direction). The thickness of the third section A3 in the vertical direction (Z-axis direction) is smaller than the thickness of the first section A1 in the vertical direction (Z-axis direction).

Further, as shown in FIG. 2, the laminate 12 includes a first laminate part 12a and a second laminate part 12b. The first laminate part 12a includes insulator layers 14a to 14c located above (on the positive side of the Z axis) an insulator layer 14d that is an intermediate insulator layer, an insulator layer 14d that is an intermediate insulator layer, and It includes a protective layer 15a. The second laminate portion 12b includes insulator layers 14e and 14f located below (on the negative side of the Z axis) the insulator layer 14d, which is an intermediate insulator layer. The second laminate section 12b further includes an insulator layer 14g and protective layers 15b and 15c. The laminate 12 is created by thermocompression bonding the first laminate section 12a, thermocompression bonding the second laminate section 12b, and then thermocompression bonding the first laminate section 12a and the second laminate section 12b. be done.

The radiation conductor layer 20 functions as a patch antenna. The radiation conductor layer 20 emits and/or receives high frequency signals. The radiation conductor layer 20 is provided on the laminate 12, as shown in FIG. The radiation conductor layer 20 is located above the insulator layer 14d, which is an intermediate insulator layer (on the positive side of the Z-axis). More specifically, the radiation conductor layer 20 is located on the upper main surface of the insulator layer 14a. The radiation conductor layer 20 has a rhombus shape with diagonal lines extending in the left-right direction and the front-back direction when viewed in the up-down direction.

A high frequency signal is transmitted to the signal conductor layer 26 . The signal conductor layer 26 is provided on the laminate 12, as shown in FIG. The signal conductor layer 26 is located below (on the negative side of the Z axis) the insulator layer 14d, which is an intermediate insulator layer. More specifically, the signal conductor layer 26 is located on the lower main surface of the insulator layer 14e. The signal conductor layer 26 has a linear shape extending in the left-right direction when viewed in the up-down direction. As shown in FIG. 2, the signal conductor layer 26 is located in a first section A1, a second section A2, and a third section A3.

A high frequency signal is transmitted to the connection conductor layer 24 . The connection conductor layer 24 is provided on the laminate 12 . The connection conductor layer 24 is located on the lower main surface (negative main surface) of the insulator layer 14d, which is an intermediate insulator layer. More specifically, the connection conductor layer 24 is located on the lower main surface of the insulator layer 14d. The connection conductor layer 24 has a linear shape extending in the left-right direction when viewed in the up-down direction. The right end portion of the connection conductor layer 24 overlaps the left end portion of the signal conductor layer 26 when viewed in the vertical direction. The connection conductor layer 24 is located in the first section A1, as shown in FIG. The connection conductor layer 24 is not located in the second section A2 and the third section A3.

The first ground conductor layer 28 is connected to ground potential. The first ground conductor layer 28 is provided on the laminate 12 . The first ground conductor layer 28 is located below the connection conductor layer 24 and the signal conductor layer 26 (on the negative side of the Z-axis). The first ground conductor layer 28 is located on the lower main surface of the insulator layer 14f. The first ground conductor layer 28 covers almost the entire lower main surface of the insulator layer 14f. As a result, the first ground conductor layer 28 overlaps at least a portion of the connection conductor layer 24 and at least a portion of the signal conductor layer 26 when viewed in the vertical direction (Z-axis direction). In this embodiment, the first ground conductor layer 28 overlaps the entire connection conductor layer 24 and the entire signal conductor layer 26 when viewed in the vertical direction. Moreover, no conductor exists between the first ground conductor layer 28 and the connection conductor layer 24. No conductor exists between the first ground conductor layer 28 and the signal conductor layer 26. Furthermore, the first ground conductor layer 28 overlaps with the radiation conductor layer 20 when viewed in the vertical direction (Z-axis direction). The first ground conductor layer 28 as described above is located in the first section A1, the second section A2, and the third section A3.

The second ground conductor layer 18 is connected to ground potential. The second ground conductor layer 18 is provided on the laminate 12 . The second ground conductor layer 18 is located above the signal conductor layer 26 (on the positive side of the Z-axis). The second ground conductor layer 18 is located on the upper main surface of the insulator layer 14g. The second ground conductor layer 18 covers almost the entire upper main surface of the insulator layer 14g. Thereby, the second ground conductor layer 18 overlaps at least a portion of the signal conductor layer 26 when viewed in the vertical direction (Z-axis direction). In this embodiment, the second ground conductor layer 18 overlaps the entire signal conductor layer 26 when viewed in the vertical direction. Moreover, no conductor other than the interlayer connection conductor v4 and the first ground conductor layer 28 exists between the second ground conductor layer 18 and the signal conductor layer 26. The second ground conductor layer 18 as described above is located in the third section A3. The second ground conductor layer 18 is not located in the first section A1 and the second section A2.

As described above, the signal conductor layer 26 forms a microstrip line structure together with the first ground conductor layer 28 in the first section A1 and the second section A2. The signal conductor layer 26 forms a strip line structure together with the first ground conductor layer 28 and the second ground conductor layer 18 in the third section A3. As a result, the characteristic impedance generated in the signal conductor layer 26 is a predetermined characteristic impedance (50Ω).

The connection conductor layer 22a is located on the upper main surface of the insulator layer 14b. The connection conductor layer 22a has a linear shape extending in the left-right direction. The left end portion of the connection conductor layer 22a overlaps with the radiation conductor layer 20 when viewed in the vertical direction.

The connection conductor layer 22b is located on the upper main surface of the insulator layer 14c. The connection conductor layer 22b has a linear shape extending in the left-right direction. The left end of the connection conductor layer 22b overlaps the left end of the connection conductor layer 24 when viewed in the vertical direction. The right end portion of the connection conductor layer 22b overlaps the right end portion of the connection conductor layer 22a when viewed in the vertical direction.

The interlayer connection conductor v1 vertically penetrates the insulator layer 14a. The interlayer connection conductor v1 is in contact with the left end portions of the radiation conductor layer 20 and the connection conductor layer 22a. Thereby, the interlayer connection conductor v1 electrically connects the radiation conductor layer 20 and the connection conductor layer 22a.

The interlayer connection conductor v2 vertically penetrates the insulator layer 14b. The interlayer connection conductor v2 is in contact with the right end of the connection conductor layer 22a and the right end of the connection conductor layer 22b. Thereby, the interlayer connection conductor v2 electrically connects the connection conductor layer 22a and the connection conductor layer 22b.

The interlayer connection conductor v3 is an example of a second interlayer connection conductor. The interlayer connection conductor v3 penetrates the insulator layer 14d and the insulator layer 14c, which are intermediate insulator layers, in the vertical direction (Z-axis direction). The interlayer connection conductor v3 is in contact with the left end of the connection conductor layer 22b and the left end of the connection conductor layer 24. Thereby, the interlayer connection conductor v3 electrically connects the connection conductor layer 22b and the connection conductor layer 24. In this way, the interlayer connection conductor v3 is electrically connected to the radiation conductor layer 20.

The interlayer connection conductor v4 is an example of a first interlayer connection conductor. The interlayer connection conductor v4 passes through the insulator layer 14e, which is the negative adjacent insulator layer, in the vertical direction (Z-axis direction). The interlayer connection conductor v4 is in contact with the right end of the connection conductor layer 24 and the left end of the signal conductor layer 26. Thereby, the interlayer connection conductor v4 electrically connects the connection conductor layer 24 and the signal conductor layer 26. Therefore, the interlayer connection conductor v4 is electrically connected to the signal conductor layer 26.

Here, the length of the current path from the interlayer connection conductor v3 to the radiation conductor layer 20 is shorter than the length of the current path from the interlayer connection conductor v4 to the radiation conductor layer 20, which will be described later. The length of the current path from the interlayer connection conductor v4 to the signal conductor layer 26 is shorter than the length of the current path from the interlayer connection conductor v3 to the signal conductor layer 26.

The second ground conductor layer 18, the radiation conductor layer 20, the connection conductor layers 22a, 22b, 24, the signal conductor layer 26, and the first ground conductor layer 28 as described above are formed on the upper main surface or the lower surface of the insulator layers 14a to 14g. It is formed by patterning a metal foil pasted on the main surface. The metal foil is, for example, copper foil. Further, the interlayer connection conductors v1 to v3 are formed, for example, by filling conductive paste into through holes vertically penetrating the insulating layers 14a to 14d, and solidifying the conductive paste by heating. The interlayer connection conductor v4 is formed by filling a through hole that vertically penetrates the insulator layer 14e with solder. In this way, the material of the interlayer connection conductor v3, which is the second interlayer connection conductor, is different from the material of the interlayer connection conductor v4, which is the first interlayer connection conductor.

The details of the structure of the connection conductor layer 24 will be described below with reference to FIG. 3. The direction in which the connection conductor layer 24 extends is defined as the stretching direction. The stretching direction is the left-right direction. The direction perpendicular to the stretching direction and the up-down direction (Z-axis direction) is defined as the line width direction. The line width direction is the front-back direction.

The connection conductor layer 24 includes a first connection section A11, a second connection section A12, a line section A31, a first intermediate section A21, and a second intermediate section A22. The first connection section A11, the first intermediate section A21, the track section A31, the second intermediate section A22, and the second connection section A12 are arranged in this order from right to left. Therefore, the first intermediate section A21 is adjacent to the first connecting section A11. The second intermediate section A22 is adjacent to the second connection section A12. The track section A31 is adjacent to the first intermediate section A21 and the second intermediate section A22. The first connection section A11 is located at the right end (first end) of the connection conductor layer 24 in the stretching direction. The second connection section A12 is located at the left end (second end) of the connection conductor layer 24 in the stretching direction. Therefore, the right end of the first connection section A11 coincides with the right end of the connection conductor layer 24. The left end of the second connection section A12 coincides with the left end of the connection conductor layer 24.

The interlayer connection conductor v4 (first interlayer connection conductor) is in contact with the first connection section A11. In the left-right direction, which is the stretching direction, both ends of the first connection section A11 are located at equal distances from the center of the interlayer connection conductor v4 (first interlayer connection conductor) when viewed in the up-down direction (Z-axis direction). Therefore, the distance from the center of the interlayer connection conductor v4 to the left end of the first connection section A11 is equal to the distance from the center of the interlayer connection conductor v4 to the right end of the first connection section A11.

The interlayer connection conductor v3 (second interlayer connection conductor) is in contact with the second connection section A12. In the left-right direction, which is the stretching direction, both ends of the second connection section A12 are located at equal distances from the center of the interlayer connection conductor v3 (second interlayer connection conductor) when viewed in the up-down direction (Z-axis direction). Therefore, the distance from the center of the interlayer connection conductor v3 to the left end of the second connection section A12 is equal to the distance from the center of the interlayer connection conductor v3 to the right end of the second connection section A12. The maximum width of the second connection section A12 in the front-rear direction (line width direction) is smaller than the maximum width of the first connection section A11 in the front-rear direction (line width direction). The first connection section A11 and the second connection section A12 have a circular shape. The diameter of the second connection section A12 is smaller than the diameter of the first connection section A11.

The first intermediate section A21 includes a first thin line section A21a and a first thick line section A21b. The first thin line section A21a has a width in the front-rear direction (line width direction) that is smaller than the width in the front-rear direction (line width direction) of the second thick line section A22b. The first thick line section A21b is adjacent to the line section A31. The first thick line section A21b has a width in the longitudinal direction (line width direction) that is larger than the width in the longitudinal direction (line width direction) of the line section A31.

The second intermediate section A22 includes a second thin line section A22a and a second thick line section A22b. The second thin line section A22a has a width in the front-rear direction (line width direction) that is smaller than the width in the front-rear direction (line width direction) of the second thick line section A22b. The second thick line section A22b is adjacent to the line section A31. The second thick line section A22b has a width in the longitudinal direction (line width direction) smaller than the width in the longitudinal direction (line width direction) of the line section A31.

[effect]
According to the multilayer substrate 10, it is possible to suppress the occurrence of characteristic impedance mismatch in the section between the signal conductor layer 26 and the radiation conductor layer 20. This will be explained below with reference to the drawings. FIG. 4 is a Smith chart. Z0 is the characteristic impedance occurring in the line section A31. Z0 is 50Ω. Z1 is the characteristic impedance occurring in the first connection section A11. Z1 is, for example, 20Ω.

More specifically, in the multilayer substrate 10, the width in the line width direction of the first connection section A11 and the second connection section A12 of the connection conductor layer 24 is larger than the width in the line width direction of the line section A31. Moreover, the interlayer connection conductor v4 is in contact with the first connection section A11. The interlayer connection conductor v3 is in contact with the second connection section A12. Therefore, the characteristic impedance generated in the first connection section A11 and the second connection section A12 of the connection conductor layer 24 tends to deviate from the desired specific impedance (50Ω).

Therefore, the connection conductor layer 24 includes the first intermediate section A21. The first intermediate section A21 includes a first thin line section A21a having a width in the line width direction smaller than the width in the line width direction of the second thick line section A22b. The first intermediate section A21 is adjacent to the first connection section A11. Thereby, the first thin line section A21a functions as an inductance. That is, an inductor is connected in series to the line section A31. Thereby, as shown by the arrow X1 of the Smith chart in FIG. 4, the first thin line section A21a rotates the impedance clockwise from Z1 as the starting point.

Further, the first intermediate section A21 includes a first thick line section A21b having a width in the line width direction larger than the width in the line width direction of the line section A31. The first thick line section A21b is adjacent to the line section A31. Further, the first thick line section A21b overlaps with the first ground conductor layer 28 when viewed in the vertical direction. Therefore, a capacitance is generated in the first thick line section A21b. That is, a capacitor is connected in parallel to the line section A31. Thereby, as shown by the arrow X2 in the Smith chart of FIG. 4, the first thick line section A21b rotates the impedance clockwise with the tip of the arrow X1 as the starting point.

As a result, the characteristic impedance occurring in the line section A31 and the characteristic impedance occurring in the first connection section A11 are matched by the first intermediate section A21. Although the explanation is omitted, based on the same principle, the characteristic impedance occurring in the line section A31 and the characteristic impedance occurring in the second connection section A12 are matched by the second intermediate section A22. As described above, according to the multilayer substrate 10, it is possible to suppress the occurrence of characteristic impedance mismatch in the section between the signal conductor layer 26 and the radiation conductor layer 20. By suppressing the occurrence of characteristic impedance mismatch in the section between the signal conductor layer 26 and the radiation conductor layer 20, the multilayer substrate 10 can have a wider band.

Moreover, according to the multilayer board 10, the first connection section A11 and the interlayer connection conductor v4 are connected more reliably. More specifically, the laminate 12 is produced by thermocompression bonding the first laminate section 12a, thermocompression bonding the second laminate section 12b, and then thermocompression bonding the first laminate section 12a and the second laminate section 12b. It is created by When the first laminate part 12a and the second laminate part 12b are bonded by thermocompression, the first connection section A11 and the interlayer connection conductor v4 are connected. Therefore, the maximum width of the first connection section A11 in the line width direction is larger than the maximum width of the second connection section A12 in the line width direction. Thereby, the first connection section A11 and the interlayer connection conductor v4 are connected more reliably.

(First modification)
The connection conductor layer 24a according to the first modification will be described below with reference to the drawings. FIG. 5 is a top view of the connection conductor layer 24a.

The connection conductor layer 24a differs from the connection conductor layer 24 in the following points.
- The width w1 of the first thick line section A21b in the line width direction is larger than the width w2 of the second thick line section A22b in the line width direction.
- The width w11 in the line width direction of the first thin line section A21a and the width w12 in the line width direction of the second thin line section A22a are smaller than the width w3 in the line width direction of the line section A31.

The other structure of the connection conductor layer 24a is the same as the structure of the connection conductor layer 24, so a description thereof will be omitted. The multilayer substrate 10 including the connection conductor layer 24a can have the same effects as the multilayer substrate 10 including the connection conductor layer 24.

Further, according to the multilayer substrate 10 including the connection conductor layer 24a, the first intermediate section A21 allows matching of the characteristic impedance occurring in the line section A31 and the characteristic impedance occurring in the first connection section A11. It will be done. The maximum width of the first connection section A11 in the line width direction is larger than the maximum width of the second connection section A12 in the line width direction. Therefore, the characteristic impedance occurring in the first connection section A11 is smaller than the characteristic impedance occurring in the second connection section A12. That is, the difference between the predetermined characteristic impedance (50Ω) and the characteristic impedance occurring in the first connection section A11 becomes large. Therefore, the width w1 of the first thick line section A21b in the line width direction is larger than the width w2 of the second thick line section A22b in the line width direction. As a result, the capacitance value generated in the first thick line section A21b increases. The width w11 in the line width direction of the first thin line section A21a and the width w12 in the line width direction of the second thin line section A22a are smaller than the width w3 in the line width direction of the line section A31. This increases the inductance value generated in the first thin line section A21a. As a result, the characteristic impedance occurring in the line section A31 and the characteristic impedance occurring in the first connection section A11 are matched by the first intermediate section A21.

(Second modification)
The connection conductor layer 24b according to the second modification will be described below with reference to the drawings. FIG. 6 is a top view of the connection conductor layer 24b.

The connection conductor layer 24b is different from the connection conductor layer 24a in the shapes of the first thick line section A21b and the second thick line section A22b. The first thick line section A21b and the second thick line section A22b have a tapered shape. The width of the first thick line section A21b and the second thick line section A22b in the line width direction becomes smaller as they approach the line section A31. As a result, rapid changes in characteristic impedance occurring in the first thick line section A21b and the second thick line section A22b are suppressed. The other structure of the connection conductor layer 24b is the same as that of the connection conductor layer 24a. The multilayer substrate 10 including the connection conductor layer 24b can have the same effects as the multilayer substrate 10 including the connection conductor layer 24a.

(Third modification)
A connection conductor layer 24c according to a third modification will be described below with reference to the drawings. FIG. 7 is a top view of the connection conductor layer 24c.

The connection conductor layer 24c differs from the connection conductor layer 24 in that the first thin line section A21a and the second thin line section A22a are not present. The first thick line section A21b is adjacent to the first connection section A11. The second thick line section A22b is adjacent to the second connection section A12. The other structure of the connection conductor layer 24c is the same as that of the connection conductor layer 24, so the description thereof will be omitted.

According to the multilayer substrate 10 including the connection conductor layer 24c, it is possible to suppress the occurrence of characteristic impedance mismatch in the section between the signal conductor layer 26 and the radiation conductor layer 20. This will be explained below with reference to the drawings. FIG. 8 is a Smith chart. Z0 is the characteristic impedance occurring in the line section A31. Z0 is 50Ω. Z1 is the characteristic impedance occurring in the first connection section A11. Z1 is, for example, 20Ω.

More specifically, in the multilayer substrate 10, the width in the line width direction of the first connection section A11 and the second connection section A12 of the connection conductor layer 24c is larger than the width in the line width direction of the line section A31. Moreover, the interlayer connection conductor v4 is in contact with the first connection section A11. The interlayer connection conductor v3 is in contact with the second connection section A12. Therefore, the characteristic impedance generated in the first connection section A11 and the second connection section A12 of the connection conductor layer 24c tends to deviate from the desired specific impedance (50Ω).

Therefore, the connection conductor layer 24c includes the first intermediate section A21. The first thick line section A21b overlaps with the first ground conductor layer 28 when viewed in the vertical direction. Thereby, the first thick line section A21b functions as a transmission line. The first intermediate section A21 includes a first thick line section A21b having a width in the line width direction larger than the width in the line width direction of the line section A31. Therefore, the characteristic impedance Z2 occurring in the first thick line section A21b is smaller than the predetermined characteristic impedance (50Ω). As a result, the impedance moves along a circle centered on the characteristic impedance Z2 occurring in the first thick line section A21b and passing through Z0. Therefore, the characteristic impedance Z2 generated in the first thick line section A21b is set to an appropriate value, and the length of the first thick line section A21b is set to an appropriate length. Thereby, the characteristic impedance occurring in the line section A31 and the characteristic impedance occurring in the first connection section A11 are matched by the first intermediate section A21. Although the explanation is omitted, based on the same principle, the characteristic impedance occurring in the line section A31 and the characteristic impedance occurring in the second connection section A12 are matched by the second intermediate section A22. As described above, the multilayer substrate 10 including the connection conductor layer 24c can suppress the occurrence of characteristic impedance mismatch in the section between the signal conductor layer 26 and the radiation conductor layer 20.

(Fourth modification)
A connection conductor layer 24d according to a fourth modification will be described below with reference to the drawings. FIG. 9 is a top view of the connection conductor layer 24d.

The connection conductor layer 24d differs from the connection conductor layer 24 in that the line section A31 is bent when viewed in the vertical direction. In this way, the line section A31 does not have to have a straight line shape. The other structure of the connection conductor layer 24d is the same as that of the connection conductor layer 24, so the description thereof will be omitted. The multilayer substrate 10 including the connection conductor layer 24d can have the same effects as the multilayer substrate 10 including the connection conductor layer 24.

(Second embodiment)
A multilayer substrate 10a according to a second embodiment will be described below with reference to the drawings. FIG. 10 is a cross-sectional view of the multilayer substrate 10a.

The multilayer substrate 10a differs from the multilayer substrate 10 in that the main insulating material of the second laminate part 12b is different from the main insulating material of the first laminate part 12a. The Young's modulus of the main insulating material of the second laminate part 12b is higher than the Young's modulus of the main insulating material of the first laminate part 12a. The material of the first laminate portion 12a is Teflon (registered trademark) or FR-4. The material of the second laminate portion 12b is, for example, polyimide or liquid crystal polymer. The other structure of the multilayer substrate 10a is the same as that of the multilayer substrate 10, so the description thereof will be omitted. The multilayer substrate 10a can have the same effects as the multilayer substrate 10.

In the multilayer substrate 10a, the Young's modulus of the main insulating material of the second laminate part 12b is higher than the Young's modulus of the main insulating material of the first laminate part 12a. Thereby, it is possible to easily process the second laminate portion 12b into any shape.

(Third embodiment)
A multilayer substrate 10b according to a third embodiment will be described below with reference to the drawings. FIG. 11 is a cross-sectional view of the multilayer substrate 10b. FIG. 12 is a top view of the connection conductor layer 24 provided on the multilayer substrate 10b.

The multilayer substrate 10b differs from the multilayer substrate 10 mainly in that the interlayer connection conductor v3 is located on the signal conductor layer 26 side, and the interlayer connection conductor v4 is located on the radiation conductor layer 20 side.

In the third embodiment, not only the insulator layers 14e and 14f but also the insulator layer 14d extend rightward from the insulator layers 14a to 14c. The insulator layer 14g is laminated on the insulator layer 14d. In the third embodiment, the insulator layer 14c corresponds to the intermediate insulator layer, and the insulator layer 14d corresponds to the negative side adjacent insulator layer.

The first stacked body portion 12a includes insulator layers 14a to 14c and a protective layer 15a. The second laminate portion 12b includes insulator layers 14d to 14g and protective layers 15b and 15c. The laminate 12 is created by thermocompression bonding the first laminate section 12a, thermocompression bonding the second laminate section 12b, and then thermocompression bonding the first laminate section 12a and the second laminate section 12b. be done.

The connection conductor layer 24 is located on the upper main surface of the insulator layer 14d. As shown in FIG. 12, the connection conductor layer 24 is provided so that the direction from the first connection section A11 to the second connection section A12 coincides with the right direction. In the third embodiment, the left end of the connection conductor layer 24 corresponds to the first end of the connection conductor layer 24, and the right end of the connection conductor layer 24 corresponds to the second end of the connection conductor layer 24.

The interlayer connection conductor v3 vertically penetrates the insulator layers 14d and 14e. The interlayer connection conductor v3 is in contact with the right end of the connection conductor layer 24, that is, the second connection section A12 of the connection conductor layer 24, and the left end of the signal conductor layer 26. Thereby, the interlayer connection conductor v3 electrically connects the connection conductor layer 24 and the signal conductor layer 26. Therefore, the interlayer connection conductor v3 is electrically connected to the signal conductor layer 26.

The interlayer connection conductor v4 vertically penetrates the insulator layer 14c. The interlayer connection conductor v4 is in contact with the left end of the connection conductor layer 22b and the left end of the connection conductor layer 24, that is, the first connection section A11 of the connection conductor layer 24. Thereby, the interlayer connection conductor v4 electrically connects the connection conductor layer 22b and the connection conductor layer 24. Therefore, the interlayer connection conductor v4 is electrically connected to the radiation conductor layer 20.

Here, the length of the current path from the interlayer connection conductor v4 to the radiation conductor layer 20 is shorter than the length of the current path from the interlayer connection conductor v3 to the radiation conductor layer 20. The length of the current path from the interlayer connection conductor v3 to the signal conductor layer 26 is shorter than the length of the current path from the interlayer connection conductor v4 to the signal conductor layer 26.

The other structure of the multilayer substrate 10b is the same as that of the multilayer substrate 10, so a description thereof will be omitted. The multilayer substrate 10b can have the same effects as the multilayer substrate 10.

(Other embodiments)
The multilayer substrate according to the present invention is not limited to the multilayer substrates 10, 10a, and 10b, and can be modified within the scope of the gist. Furthermore, the structures of the multilayer substrates 10, 10a, and 10b may be combined arbitrarily. Furthermore, the structures of the connection conductor layers 24, 24a to 24d may be combined arbitrarily.

Note that the width in the line width direction of the first thick line section A21b may be less than or equal to the width in the line width direction of the second thick line section A22b.

Note that the width in the line width direction of the first thin line section A21a and the width in the line width direction of the second thin line section A22a may be greater than or equal to the width in the line width direction of the line section A31.

Note that the multilayer substrates 10, 10a, and 10b may further include a ground conductor located above the signal conductor layer 26 and overlapping with the signal conductor layer 26 when viewed in the vertical direction.

Note that the laminate 12 does not need to have flexibility.

Note that the material of the insulator layers 14a to 14g may be a material other than thermoplastic resin.

Note that the material of the interlayer connection conductor v3, which is the second interlayer connection conductor, may be the same as the material of the interlayer connection conductor v4, which is the first interlayer connection conductor.

The present invention includes the following structure.

(1)
A laminate having a structure in which a plurality of insulator layers including an intermediate insulator layer and a negative adjacent insulator layer are stacked in alignment in the Z-axis direction, and each of the plurality of insulator layers has a positive main surface. , and has a negative main surface located on the negative side of the Z-axis from the positive main surface, and the negative side adjacent insulator layer is located on the negative side of the Z-axis of the intermediate insulator layer, and a laminate in contact with the intermediate insulator layer;
a radiation conductor layer provided in the laminate and located on the positive side of the Z axis from the intermediate insulator layer;
a signal conductor layer provided in the laminate and located on the negative side of the Z axis from the intermediate insulator layer;
provided in the laminate, located on the negative main surface of the intermediate insulator layer, and including a first connection section, a second connection section, a line section, a first intermediate section, and a second intermediate section. the first intermediate section is adjacent to the first connection section, the second intermediate section is adjacent to the second connection section, and the line section is a connecting conductor layer adjacent to the first intermediate section and the second intermediate section;
provided in the laminate, located on the negative side of the Z-axis relative to the connection conductor layer and the signal conductor layer, and viewed in the Z-axis direction, at least a portion of the connection conductor layer and the a first ground conductor layer overlapping at least a portion of the signal conductor layer;
a first interlayer connection conductor in contact with the first connection section;
a second interlayer connection conductor in contact with the second connection section;
It is equipped with
One of the first interlayer connection conductor and the second interlayer connection conductor penetrates the intermediate insulator layer in the Z-axis direction and electrically connects the radiation conductor layer and the connection conductor layer. Ori,
The other of the first interlayer connection conductor and the second interlayer connection conductor penetrates the negative adjacent insulator layer in the Z-axis direction and electrically connects the signal conductor layer and the connection conductor layer. and
The direction in which the connecting conductor layer extends is defined as the stretching direction,
A direction perpendicular to the stretching direction and the Z-axis direction is defined as the line width direction,
The first connection section is located at a first end of the connection conductor layer in the stretching direction, and the second connection section is located at a second end of the connection conductor layer in the stretching direction, In the stretching direction, the second end of the connection conductor layer is located on the opposite side of the first end of the connection conductor layer,
In the stretching direction, both ends of the first connection section are located at equal distances from the center of the first interlayer connection conductor as seen in the Z-axis direction,
In the stretching direction, both ends of the second connection section are located at equal distances from the center of the second interlayer connection conductor as viewed in the Z-axis direction,
The maximum width of the second connection section in the line width direction is smaller than the maximum width of the first connection section in the line width direction,
The first intermediate section includes a first thick line section having a width in the line width direction that is larger than a width in the line width direction of the line section,
The second intermediate section includes a second thick line section having a width in the line width direction that is larger than the width in the line width direction of the line section,
The first thick line section and the second thick line section are adjacent to the railway line section,
Multilayer board.

(2)
The width of the first thick line section in the line width direction is larger than the width of the second thick line section in the line width direction.
The multilayer substrate according to (1).

(3)
The first intermediate section includes a first thin line section having a width in the line width direction smaller than the width in the line width direction of the first thick line section,
The second intermediate section includes a second thin line section having a width in the line width direction smaller than the width in the line width direction of the second thick line section,
The first thin line section is adjacent to the first connection section,
The second thin line section is adjacent to the second connection section,
The multilayer substrate according to either (1) or (2).

(4)
The width of the first thin line section in the line width direction and the width of the second thin line section in the line width direction are smaller than the width of the line section in the line width direction.
The multilayer substrate according to (3).

(5)
The first ground conductor layer overlaps the radiation conductor layer when viewed in the Z-axis direction.
The multilayer substrate according to any one of (1) to (4).

(6)
The laminate has a first section and a second section arranged in the X-axis direction perpendicular to the Z-axis direction,
The thickness of the first section in the Z-axis direction is greater than the thickness of the second section in the Z-axis direction,
The connection conductor layer is located in the first section,
The signal conductor layer is located in the first section and the second section,
The multilayer substrate according to any one of (1) to (5).

(7)
The laminate has a first section, a second section, and a third section arranged in this order in the X-axis direction perpendicular to the Z-axis direction,
The thickness of the first section in the Z-axis direction is greater than the thickness of the second section in the Z-axis direction,
The thickness of the third section in the Z-axis direction is greater than the thickness of the second section in the Z-axis direction,
The multilayer substrate includes:
A second ground conductor layer located in the third section and not located in the first section and the second section,
Furthermore, we are equipped with
The first ground conductor layer is located in the first section, the second section, and the third section,
The second ground conductor layer is located on the positive side of the Z-axis from the signal conductor layer, and overlaps at least a portion of the signal conductor layer when viewed in the Z-axis direction,
The signal conductor layer forms a microstrip line structure together with the first ground conductor layer in the first section and the second section,
The signal conductor layer forms a strip line structure together with the first ground conductor layer and the second ground conductor layer in the third section.
The multilayer substrate according to any one of (1) to (6).

(8)
The laminate includes a first laminate part and a second laminate part,
The first laminate section includes one or more of the insulator layers and the intermediate insulator layer located on the positive side of the Z-axis from the intermediate insulator layer,
The second laminate section includes one or more of the insulator layers located on the negative side of the Z axis than the intermediate insulator layer,
The main insulating material of the second laminate part is different from the main insulating material of the first laminate part,
The multilayer substrate according to any one of (1) to (7).

(9)
The Young's modulus of the main insulating material of the second laminate part is higher than the Young's modulus of the main insulating material of the first laminate part.
The multilayer substrate according to (8).

(10)
The material of the second interlayer connection conductor is different from the material of the first interlayer connection conductor,
The multilayer substrate according to either (8) or (9).

(11)
The laminate has flexibility,
The multilayer substrate according to any one of (1) to (10).

(12)
The material of the plurality of insulator layers is a thermoplastic resin,
The multilayer substrate according to any one of (1) to (11).

10, 10a, 10b: Multilayer substrate 12: Laminated body 12a: First laminated body part 12b: Second laminated body parts 14a to 14g: Insulator layers 15a to 15c: Protective layer 18: Second ground conductor layer 20: Radiation conductor Layers 22a, 22b, 24, 24a to 24d: Connection conductor layer 26: Signal conductor layer 28: First ground conductor layer A1: First section A11: First connection section A12: Second connection section A2: Second section A21: First intermediate section A21b: First thick line section A21a: First thin line section A22: Second intermediate section A22b: Second thick line section A22a: Second thin line section A3: Third section A31: Line section v1 to v4: Interlayer connection conductor

Claims (12)

A laminate having a structure in which a plurality of insulator layers including an intermediate insulator layer and a negative adjacent insulator layer are stacked in alignment in the Z-axis direction, and each of the plurality of insulator layers has a positive main surface. , and has a negative main surface located on the negative side of the Z axis from the positive main surface, and the negative side adjacent insulator layer is located on the negative side of the Z axis of the intermediate insulator layer, and a laminate in contact with the intermediate insulator layer;
a radiation conductor layer provided in the laminate and located on the positive side of the Z axis from the intermediate insulator layer;
a signal conductor layer provided in the laminate and located on the negative side of the Z axis from the intermediate insulator layer;
provided in the laminate, located on the negative main surface of the intermediate insulator layer, and including a first connection section, a second connection section, a line section, a first intermediate section, and a second intermediate section. the first intermediate section is adjacent to the first connection section, the second intermediate section is adjacent to the second connection section, and the line section is a connecting conductor layer adjacent to the first intermediate section and the second intermediate section;
provided in the laminate, located on the negative side of the Z-axis relative to the connection conductor layer and the signal conductor layer, and viewed in the Z-axis direction, at least a portion of the connection conductor layer and the a first ground conductor layer overlapping at least a portion of the signal conductor layer;
a first interlayer connection conductor in contact with the first connection section;
a second interlayer connection conductor in contact with the second connection section;
It is equipped with
One of the first interlayer connection conductor and the second interlayer connection conductor penetrates the intermediate insulator layer in the Z-axis direction and electrically connects the radiation conductor layer and the connection conductor layer. Ori,
The other of the first interlayer connection conductor and the second interlayer connection conductor penetrates the negative adjacent insulator layer in the Z-axis direction and electrically connects the signal conductor layer and the connection conductor layer. and
The direction in which the connecting conductor layer extends is defined as the stretching direction,
A direction perpendicular to the stretching direction and the Z-axis direction is defined as the line width direction,
The first connection section is located at a first end of the connection conductor layer in the stretching direction, and the second connection section is located at a second end of the connection conductor layer in the stretching direction, In the stretching direction, the second end of the connection conductor layer is located on the opposite side of the first end of the connection conductor layer,
In the stretching direction, both ends of the first connection section are located at equal distances from the center of the first interlayer connection conductor as seen in the Z-axis direction,
In the stretching direction, both ends of the second connection section are located at equal distances from the center of the second interlayer connection conductor as viewed in the Z-axis direction,
The maximum width of the second connection section in the line width direction is smaller than the maximum width of the first connection section in the line width direction,
The first intermediate section includes a first thick line section having a width in the line width direction that is larger than a width in the line width direction of the line section,
The second intermediate section includes a second thick line section having a width in the line width direction that is larger than the width in the line width direction of the line section,
The first thick line section and the second thick line section are adjacent to the railway line section,
Multilayer board. The width of the first thick line section in the line width direction is larger than the width of the second thick line section in the line width direction.
The multilayer substrate according to claim 1. The first intermediate section includes a first thin line section having a width in the line width direction smaller than the width in the line width direction of the first thick line section,
The second intermediate section includes a second thin line section having a width in the line width direction smaller than the width in the line width direction of the second thick line section,
The first thin line section is adjacent to the first connection section,
The second thin line section is adjacent to the second connection section,
The multilayer substrate according to claim 1 or 2. The width of the first thin line section in the line width direction and the width of the second thin line section in the line width direction are smaller than the width of the line section in the line width direction.
The multilayer substrate according to claim 3. The first ground conductor layer overlaps the radiation conductor layer when viewed in the Z-axis direction.
The multilayer substrate according to claim 1 or claim 2. The laminate has a first section and a second section arranged in the X-axis direction perpendicular to the Z-axis direction,
The thickness of the first section in the Z-axis direction is greater than the thickness of the second section in the Z-axis direction,
The connection conductor layer is located in the first section,
The signal conductor layer is located in the first section and the second section,
The multilayer substrate according to claim 1 or claim 2. The laminate has a first section, a second section, and a third section arranged in this order in the X-axis direction perpendicular to the Z-axis direction,
The thickness of the first section in the Z-axis direction is greater than the thickness of the second section in the Z-axis direction,
The thickness of the third section in the Z-axis direction is greater than the thickness of the second section in the Z-axis direction,
The multilayer substrate includes:
A second ground conductor layer located in the third section and not located in the first section and the second section,
Furthermore, we are equipped with
The first ground conductor layer is located in the first section, the second section, and the third section,
The second ground conductor layer is located on the positive side of the Z-axis from the signal conductor layer, and overlaps at least a portion of the signal conductor layer when viewed in the Z-axis direction,
The signal conductor layer forms a microstrip line structure together with the first ground conductor layer in the first section and the second section,
The signal conductor layer forms a strip line structure together with the first ground conductor layer and the second ground conductor layer in the third section.
The multilayer substrate according to claim 1 or claim 2. The laminate includes a first laminate part and a second laminate part,
The first laminate section includes one or more of the insulator layers and the intermediate insulator layer located on the positive side of the Z-axis from the intermediate insulator layer,
The second laminate section includes one or more of the insulator layers located on the negative side of the Z axis than the intermediate insulator layer,
The main insulating material of the second laminate part is different from the main insulating material of the first laminate part,
The multilayer substrate according to claim 1 or claim 2. The Young's modulus of the main insulating material of the second laminate part is higher than the Young's modulus of the main insulating material of the first laminate part.
The multilayer substrate according to claim 8. The material of the second interlayer connection conductor is different from the material of the first interlayer connection conductor,
The multilayer substrate according to claim 8. The laminate has flexibility,
The multilayer substrate according to claim 1 or claim 2. The material of the plurality of insulator layers is a thermoplastic resin,
The multilayer substrate according to claim 1 or claim 2.

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