Printed wiring board

Abstract

A printed wiring board according to the present invention comprises a stacked body and a first conductor pattern. The stacked body has a plurality of stacked dielectric layers, and has a first surface and a second surface opposite of the first surface in the stacking direction of the plurality of dielectric layers. The stacked body has an incident port on the first surface and a first waveguide connected to the incident port inside the stacked body. The first conductor pattern has an antenna that is disposed on the second surface and radiates electromagnetic waves, which are incident from the incident port and propagate through the first waveguide.

Description

printed wiring board

[0001] The present disclosure relates to a printed wiring board. This application claims priority to Japanese Patent Application No. 2024-088764, filed on May 31, 2024. The entire contents of the Japanese patent application are incorporated herein by reference.

[0002] International Publication No. 2021 / 010125 (Patent Document 1) describes an antenna module. The antenna module described in Patent Document 1 includes a substrate and a conductor pattern formed on a main surface of the substrate, the conductor pattern including an antenna and wiring connected to the antenna.

[0003] International Publication No. 2021 / 010125

[0004] The printed wiring board of the present disclosure includes a laminate and a first conductor pattern. The laminate has a plurality of stacked dielectric layers and has a first surface and a second surface opposite the first surface in the stacking direction of the plurality of dielectric layers. The laminate has an incident port on the first surface and a first waveguide inside the laminate connected to the incident port. The first conductor pattern has an antenna disposed on the second surface and radiates electromagnetic waves incident from the incident port and propagating through the first waveguide.

[0005] FIG. 1 is a cross-sectional view of printed wiring board 100. FIG. 2 is a partial plan view of printed wiring board 100. FIG. 3 is a partial plan view of printed wiring board 100 with dielectric layer 13 not shown. FIG. 4 is a schematic cross-sectional view showing an example of use of printed wiring board 100. FIG. 5 is a manufacturing process diagram of printed wiring board 100. FIG. 6 is a cross-sectional view illustrating patterning step S2. FIG. 7 is a cross-sectional view illustrating hole drilling step S3. FIG. 8 is a cross-sectional view illustrating conductor layer forming step S4. FIG. 9 is a cross-sectional view illustrating dielectric layer attaching step S5. FIG. 10 is a cross-sectional view of printed wiring board 100 according to a modified example. FIG. 11 is a cross-sectional view of printed wiring board 100A. FIG. 12 is a cross-sectional view of printed wiring board 300. FIG. 13 is a cross-sectional view of printed wiring board 300 according to a modified example.

[0006] [Problem to be Solved by the Present Disclosure] The antenna module described in Patent Document 1 leaves room for improvement in the degree of freedom in designing the propagation path of the electromagnetic waves. The present disclosure provides a printed wiring board that improves the degree of freedom in designing the propagation path of the electromagnetic waves.

[0007] [Effects of the Present Disclosure] According to the printed wiring board of the present disclosure, it is possible to improve the degree of freedom in designing the propagation path of electromagnetic waves.

[0008] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described.

[0009] (1) A printed wiring board according to an embodiment includes a laminate and a first conductor pattern. The laminate has a plurality of dielectric layers stacked one on the other, and has a first surface and a second surface opposite the first surface in the stacking direction of the dielectric layers. The laminate has an incident port on the first surface, and has a first waveguide inside the laminate connected to the incident port. The first conductor pattern has an antenna disposed on the second surface, and radiates electromagnetic waves incident from the incident port and propagating through the first waveguide. The printed wiring board of (1) above improves the design freedom of the propagation path of the electromagnetic waves.

[0010] (2) The printed wiring board of (1) above may further include a second conductor pattern, a third conductor pattern, and a plurality of first conductor layers. The plurality of dielectric layers may include a first dielectric layer located closest to the first surface. The first dielectric layer may have, in the stacking direction, a first main surface forming the first surface and a second main surface opposite the first main surface. The second conductor pattern may be disposed on the first main surface and may have an opening forming an entrance. The third conductor pattern may sandwich the first dielectric layer between itself and the second conductor pattern. Each of the plurality of first conductor layers may be formed in the first dielectric layer so as to electrically connect the second conductor pattern and the third conductor pattern. The first waveguide may be a portion of the first dielectric layer defined by the second conductor pattern, the third conductor pattern, and the plurality of first conductor layers.

[0011] (3) In the printed wiring board of (1), the plurality of dielectric layers may include a second dielectric layer located closest to the second surface. The second dielectric layer may be disposed on the second main surface. The first conductor pattern may be disposed on the second dielectric layer.

[0012] (4) In the printed wiring board of (3), the first dielectric layer may be a first fluororesin layer, and the second dielectric layer may be a first adhesive layer and a second fluororesin layer disposed on the first adhesive layer.

[0013] (5) In the printed wiring board of (3), the first dielectric layer may be a first fluororesin layer and a first adhesive layer disposed on the first fluororesin layer, and the second dielectric layer may be a second fluororesin layer.

[0014] (6) In the printed wiring board of (4) or (5), the difference between the dielectric constant of the first fluororesin layer and the dielectric constant of the first adhesive layer may be 0.2 or less. The printed wiring board of (6) can reduce loss when electromagnetic waves propagate through the waveguide.

[0015] (7) In the printed wiring board of (4) or (5), the difference between the dielectric loss tangent of the first fluororesin layer and the dielectric loss tangent of the first adhesive layer may be 0.005 or less. The printed wiring board of (7) can reduce loss when electromagnetic waves propagate through the waveguide.

[0016] (8) The printed wiring boards of (2) to (7) above may further include a fourth conductor pattern and a plurality of second conductor layers. The laminate may have a second waveguide connected to the first waveguide inside the laminate. The plurality of dielectric layers may further include a second dielectric layer. The second dielectric layer may be disposed on the second main surface. The fourth conductor pattern may sandwich the second dielectric layer between itself and the third conductor pattern. Each of the plurality of second conductor layers may be formed within the second dielectric layer so as to electrically connect the third conductor pattern and the fourth conductor pattern. The second waveguide may be a portion of the second dielectric layer defined by the third conductor pattern, the fourth conductor pattern, and the plurality of second conductor layers. The printed wiring board of (8) above further improves the design freedom of the propagation path of the electromagnetic wave.

[0017] [Details of the embodiment of the present disclosure] Details of the embodiment of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and redundant description will not be repeated.

[0018] First Embodiment A printed wiring board according to a first embodiment will be described. The printed wiring board according to the first embodiment is designated as a printed wiring board 100.

[0019] <Configuration of Printed Wiring Board 100> The configuration of the printed wiring board 100 will be described below.

[0020] Fig. 1 is a cross-sectional view of a printed wiring board 100. Fig. 2 is a partial plan view of the printed wiring board 100. Fig. 3 is a partial plan view of the printed wiring board 100, omitting the illustration of the dielectric layer 13. As shown in Figs. 1, 2, and 3, the printed wiring board 100 has a laminate 10, a conductor pattern 20, a conductor pattern 30, a conductor pattern 40, and a plurality of conductor layers 50.

[0021] The laminate 10 has a plurality of stacked dielectric layers 11. In the example shown in Fig. 1, the number of stacked dielectric layers 11 is two. The direction in which the plurality of dielectric layers 11 are stacked is defined as a direction DR. The laminate 10 has a first surface 10a and a second surface 10b in the direction DR. The second surface 10b is the surface opposite to the first surface 10a.

[0022] Of the multiple dielectric layers 11, the dielectric layer 11 located closest to the first surface 10a is referred to as the dielectric layer 12. The dielectric layer 12 has a main surface 12a and a main surface 12b in the direction DR. The main surface 12a forms the first surface 10a. The main surface 12b is the surface opposite to the main surface 12a. The dielectric layer 12 is, for example, a layer formed of a fluororesin (fluororesin layer).

[0023] The conductor pattern 30 is made of, for example, copper or a copper alloy. The conductor pattern 30 is disposed on the principal surface 12a (first surface 10a). An opening 30a is formed in the conductor pattern 30. The opening 30a penetrates the conductor pattern 30 along the direction DR. That is, the principal surface 12a (first surface 10a) is exposed through the opening 30a.

[0024] The conductor pattern 40 is made of, for example, copper or a copper alloy. The conductor pattern 40 is disposed on the main surface 12b. From another perspective, the conductor pattern 40 sandwiches the dielectric layer 12 between itself and the conductor pattern 30. An opening 40a is formed in the conductor pattern 40. The opening 40a penetrates the conductor pattern 40 along the direction DR. In other words, the main surface 12b is exposed from the opening 40a.

[0025] A plurality of through holes 12c are formed in the dielectric layer 12 and the conductor pattern 40. The through holes 12c penetrate the dielectric layer 12 and the conductor pattern 40 along the direction DR. That is, the conductor pattern 30 is exposed from the bottom surface of the through holes 12c. The plurality of through holes 12c are arranged in a row in a plan view. The distance between two adjacent through holes 12c is set to 0.5 times or less the wavelength of an electromagnetic wave passing through the waveguide 10c described below.

[0026] The conductor layer 50 is disposed on the inner wall surface and bottom surface of the through hole 12c. This electrically connects the conductor pattern 40 to the conductor pattern 30. The conductor layer 50 is formed of, for example, copper or a copper alloy. The conductor layer 50 may also be disposed on the conductor pattern 40. As long as the conductor layer 50 is disposed on the inner wall surface and bottom surface of the through hole 12c, it is not necessary for the conductor layer 50 to completely fill the through hole 12c.

[0027] The dielectric layer 12 located on the path between the openings 30a and 40a in plan view is surrounded by a plurality of through holes 12c in plan view and is sandwiched between the conductor patterns 30 and 40 in the direction DR. Electromagnetic waves do not leak from the portion of the dielectric layer 12 defined by the conductor layer 50, conductor patterns 30, and conductor patterns 40 arranged in the through holes 12c, and electromagnetic waves incident from the opening 30a propagate through the dielectric layer 12 in that portion and exit from the opening 40a. In this way, the portion of the dielectric layer 12 defined by the conductor layer 50, conductor patterns 30, and conductor patterns 40 arranged in the through holes 12c forms a waveguide 10c. The openings 30a and 40a form the entrance and exit of the waveguide 10c, respectively.

[0028] Of the plurality of dielectric layers 11, the dielectric layer 11 located closest to the second surface 10b is referred to as the dielectric layer 13. A conductor pattern 40 is disposed between the dielectric layer 12 and the dielectric layer 13. The dielectric layer 13 has an adhesive layer 13a and a fluororesin layer 13b.

[0029] The adhesive layer 13a is disposed on the dielectric layer 12 (on the main surface 12b) so as to cover the conductor pattern 40 and the conductor layer 50. The adhesive layer 13a is a layer formed of an adhesive. The fluororesin layer 13b is a layer formed of a fluororesin. The difference between the dielectric constant of the dielectric layer 12 (fluororesin layer) and the dielectric constant of the adhesive layer 13a is, for example, 0.2 or less. The difference between the dielectric tangent of the dielectric layer 12 (fluororesin layer) and the dielectric tangent of the adhesive layer 13a is, for example, 0.005 or less. The difference between the dielectric constant of the fluororesin layer 13b and the dielectric constant of the adhesive layer 13a is, for example, 0.2 or less. The difference between the dielectric tangent of the fluororesin layer 13b and the dielectric tangent of the adhesive layer 13a is, for example, 0.005 or less. The values ​​of the dielectric constant and dielectric tangent are measured by a split cylinder method or a phase difference method.

[0030] The conductor pattern 20 is made of, for example, copper or a copper alloy. The conductor pattern 20 is disposed on the dielectric layer 13 (on the fluororesin layer 13b). That is, the conductor pattern 20 is disposed on the second surface 10b. The conductor pattern 20 includes an antenna 21 and wiring 22.

[0031] The antenna 21 is, for example, a patch antenna. The antenna 21 has, for example, a circular or rectangular shape in a plan view. One end of the wiring 22 is connected to the antenna 21. The other end of the wiring 22 overlaps with the opening 40a in a plan view. The electromagnetic waves propagating through the waveguide 10c further propagate through the dielectric layer 13 (adhesive layer 13a, fluororesin layer 13b) and the wiring 22, and reach the antenna 21. The electromagnetic waves that have reached the antenna 21 are radiated from the antenna 21.

[0032] FIG. 4 is a schematic cross-sectional view showing an example of use of the printed wiring board 100. As shown in FIG. 4, the printed wiring board 100 is disposed above a substrate 200. The substrate 200 is, for example, a rigid substrate. The substrate 200 has a main surface 200a and a main surface 200b opposite the main surface 200a, and the main surface 200b is disposed so as to face the conductor pattern 30. An integrated circuit (IC) 210 is mounted on the main surface 200a. The IC 210 generates electromagnetic waves. The electromagnetic waves generated by the IC 210 propagate through a waveguide 200c formed to penetrate the substrate 200, enter the waveguide 10c through an opening 30a (the entrance port of the waveguide 10c), propagate through the waveguide 10c, the dielectric layer 13, and the wiring 22, and are radiated from the antenna 21. Although not shown, the IC 210 may be mounted on the main surface 200a. Also, although not shown, the printed wiring board 100 may be attached to the substrate 200.

[0033] <Method for Manufacturing Printed Wiring Board 100> A method for manufacturing the printed wiring board 100 will be described below.

[0034] 5 is a manufacturing process diagram of the printed wiring board 100. As shown in FIG. 5, the manufacturing method of the printed wiring board 100 includes a preparation step S1, a patterning step S2, a hole drilling step S3, a conductor layer forming step S4, a dielectric layer attaching step S5, and a patterning step S6.

[0035] In the preparation step S1, a dielectric layer 12 is prepared. The dielectric layer 12 prepared in the preparation step S1 has a conductor pattern 30 on a main surface 12a and a conductor pattern 40 on a main surface 12b.

[0036] 6 is a cross-sectional view illustrating the patterning step S2. In the patterning step S2, the conductor pattern 40 is patterned so as to form an opening 40a, as shown in FIG. The conductor pattern 40 is patterned by etching the conductor pattern 40 using a resist pattern formed on the conductor pattern 40 as a mask. The resist pattern is formed, for example, by applying a dry film resist onto the conductor pattern 40 and then exposing and developing the dry film resist.

[0037] Fig. 7 is a cross-sectional view illustrating the hole-making step S3. As shown in Fig. 7, in the hole-making step S3, through holes 12c are formed in the conductor pattern 40 and the dielectric layer 12 by, for example, laser processing or drilling. Fig. 8 is a cross-sectional view illustrating the conductor layer-forming step S4. As shown in Fig. 8, in the conductor layer-forming step S4, a conductor layer 50 is formed by, for example, electroless plating.

[0038] 9 is a cross-sectional view illustrating the dielectric layer attachment step S5. As shown in FIG. 9, in the dielectric layer attachment step S5, the dielectric layer 13 is attached onto the dielectric layer 12. In the dielectric layer attachment step S5, first, the dielectric layer 13 is prepared. At this stage, the adhesive layer 13a is uncured, and a conductor pattern 20 is disposed on the surface of the fluororesin layer 13b opposite the adhesive layer 13a. Second, the dielectric layer 13 is disposed on the dielectric layer 12 so that the adhesive layer 13a faces the dielectric layer 12. Third, the dielectric layer 13 is heat-pressed against the dielectric layer 12. This hardens the adhesive layer 13a, and the dielectric layer 13 is attached onto the dielectric layer 12.

[0039] In the patterning step S6, the conductor pattern 20 is patterned in the same manner as in the patterning step S2 so as to have the antenna 21 and the wiring 22. At this time, the conductor pattern 30 is also patterned, and an opening 30a is formed. In this manner, the structure of the printed wiring board 100 shown in FIGS. 1 to 3 is formed.

[0040] <Modification> Fig. 10 is a cross-sectional view of a printed wiring board 100 according to a modification. As shown in Fig. 10, the dielectric layer 12 may have a fluororesin layer 12d and an adhesive layer 13a, and the dielectric layer 13 may be a fluororesin layer. The dielectric layer 13 has a main surface 13c and a main surface 13d opposite the main surface 13c, which forms the second surface 10b. A conductor pattern 40 is disposed on the main surface 13c. A through hole 12c is formed to penetrate the conductor pattern 30, the fluororesin layer 12d, and the adhesive layer 13a. A conductor layer 50 is disposed on the inner wall surface of the through hole 12c, on the bottom surface of the through hole 12c, and on the conductor pattern 30 around the through hole 12c. In this case as well, the portion of the dielectric layer 12 defined by the plurality of conductor layers 50, the conductor patterns 30, and the conductor pattern 40 forms a waveguide 10c.

[0041] In the method for manufacturing the printed wiring board 100 according to the modified example, the steps are performed in the following order: preparation step S1, patterning step S2, dielectric layer attachment step S5, hole drilling step S3, conductor layer formation step S4, and patterning step S6. In the method for manufacturing the printed wiring board 100 according to the modified example, in the preparation step S1, a dielectric layer 13 having conductor patterns 40 and 20 on the main surface 13c and the main surface 13d, respectively, is prepared. In the method for manufacturing the printed wiring board 100 according to the modified example, the patterning step S2 is performed after the preparation step S1, and the conductor pattern 40 is patterned to have an opening 40a.

[0042] Thereafter, a dielectric layer attaching step S5 is performed, in which the dielectric layer 12 is attached to the dielectric layer 13. After the dielectric layer attaching step S5, a hole drilling step S3 is performed, in which the through-hole 12c is formed. After the hole drilling step S3, a conductor layer 50 is formed in a conductor layer forming step S4. After the conductor layer forming step S4, a patterning step S6 is performed, in which the conductor pattern 20 is patterned to have the antenna 21 and the wiring 22, and the conductor pattern 30 is patterned to have the opening 30a. As a result of the above, the structure shown in FIG. 10 is formed.

[0043] <Effects of Printed Wiring Board 100> The effects of printed wiring board 100 will be described below in comparison with a printed wiring board according to a comparative example (printed wiring board 100A).

[0044] Fig. 11 is a cross-sectional view of printed wiring board 100A. As shown in Fig. 11, printed wiring board 100A has a dielectric layer 14, a conductor pattern 20, and a conductor pattern 30. Dielectric layer 14 has a main surface 14a and a main surface 14b. Conductive patterns 30 and 20 are arranged on main surface 14a and main surface 14b, respectively.

[0045] The propagation distance of the electromagnetic wave to one antenna 21 and the propagation distance of the electromagnetic wave to another antenna 21 must be equal. Printed wiring board 100A does not have waveguide 10c, and the propagation distance of the electromagnetic wave must be adjusted only by wiring 22. Therefore, printed wiring board 100A has a low degree of freedom in designing wiring 22 (degree of freedom in designing the propagation path of the electromagnetic wave), and in some cases, overlapping between wiring 22 connected to one antenna 21 and wiring 22 connected to another antenna 21 cannot be resolved, making the design itself impossible.

[0046] On the other hand, since the printed wiring board 100 has the waveguide 10c in the laminate 10 (in the dielectric layer 12), it is possible to adjust the propagation distance of the electromagnetic wave by both the wiring 22 and the waveguide 10c. Therefore, the printed wiring board 100 has a high degree of freedom in designing the propagation path of the electromagnetic wave, and it is possible to avoid a situation in which the design becomes impossible due to the overlap of the wiring 22 connected to one antenna 21 with the wiring 22 connected to another antenna 21.

[0047] In printed wiring board 100, electromagnetic waves propagate through the two fluororesin layers before reaching wiring 22, and therefore also propagate through adhesive layer 12b. When the difference between the dielectric constant of dielectric layer 12 (fluororesin layer) or fluororesin layer 13b and the dielectric constant of adhesive layer 13a is 0.2 or less, the loss of electromagnetic waves propagating through adhesive layer 12b can be reduced. This also applies when the difference between the dielectric loss tangent of dielectric layer 12 (fluororesin layer) or fluororesin layer 13b and the dielectric loss tangent of adhesive layer 13a is 0.005 or less.

[0048] Second Embodiment A printed wiring board according to a second embodiment will be described. The printed wiring board according to the second embodiment is designated as printed wiring board 300. Here, differences from printed wiring board 100 will be mainly described, and overlapping descriptions will not be repeated.

[0049] <Configuration of Printed Wiring Board 300> The configuration of the printed wiring board 300 will be described below.

[0050] 12 is a cross-sectional view of printed wiring board 300. As shown in Fig. 12, printed wiring board 300 has laminate 10, conductor pattern 20, conductor pattern 20 and conductor pattern 30, and a plurality of conductor layers 50. In this respect, the configuration of printed wiring board 300 is common to the configuration of printed wiring board 100.

[0051] In the printed wiring board 300, the multiple dielectric layers 11 include a dielectric layer 15. The dielectric layer 15 is disposed between the dielectric layer 12 and the dielectric layer 13. The dielectric layer 15 has a main surface 15a facing the dielectric layer 12 and a main surface 15b opposite the main surface 15a and facing the dielectric layer 13. The dielectric layer 15 has an adhesive layer 15c and a fluororesin layer 15d. The adhesive layer 15c forms the main surface 15a. The fluororesin layer 15d is disposed on the adhesive layer 15c and forms the main surface 15b.

[0052] The printed wiring board 300 further includes a conductor pattern 60. The conductor pattern 60 is made of, for example, copper or a copper alloy. The conductor pattern 60 is disposed on the main surface 15b. That is, the conductor pattern 60 is disposed between the dielectric layer 13 and the dielectric layer 15, sandwiching the dielectric layer 15 between the conductor pattern 60 and the conductor pattern 40. An opening 60a is formed in the conductor pattern 60, penetrating the conductor pattern 60 along the direction DR.

[0053] A plurality of through holes 15e are formed in the dielectric layer 15 and the conductor pattern 60. The through holes 15e penetrate the dielectric layer 15 and the conductor pattern 60 along the direction DR. The plurality of through holes 15e are arranged in a row in a plan view. The distance between two adjacent through holes 15e is equal to or less than 0.5 times the wavelength of an electromagnetic wave propagating in the waveguide 10d described below.

[0054] The printed wiring board 300 further has a plurality of conductor layers 70. The conductor layers 70 are arranged on the inner wall surfaces and bottom surfaces of the through holes 15e. This electrically connects the conductor pattern 60 to the conductor pattern 40. The conductor layers 70 may also be arranged on the conductor patterns 60. As long as the conductor layers 70 are arranged on the inner wall surfaces and bottom surfaces of the through holes 15e, it is not necessary for the conductor layers 70 to completely fill the through holes 15e.

[0055] In the printed wiring board 300, the dielectric layer 15 has a portion surrounded by the conductor layer 70 disposed in the through hole 15e in a plan view, and this portion is sandwiched between the conductor pattern 60 and the conductor pattern 40. This portion of the dielectric layer 15 forms the waveguide 10d. The waveguides 10c and 10d are connected to each other through the opening 40a. That is, the electromagnetic waves propagating in the waveguide 10c further propagate in the waveguide 10d, and the electromagnetic waves propagating in the waveguide 10d propagate in the dielectric layer 13 to reach the wiring 22 and are radiated from the antenna 21. In these respects, the configuration of the printed wiring board 300 differs from the configuration of the printed wiring board 100.

[0056] <Modification> Fig. 13 is a cross-sectional view of a printed wiring board 300 according to a modification. As shown in Fig. 13, the dielectric layer 12 may have a fluororesin layer 12d and an adhesive layer 15c, and the dielectric layer 15 may be a fluororesin layer. The through hole 12c is formed to penetrate the conductor pattern 30, the fluororesin layer 12d, and the adhesive layer 15c. The conductor layer 50 is disposed on the inner wall surface of the through hole 12c, on the bottom surface of the through hole 12c, and on the conductor pattern 30 around the through hole 12c. Furthermore, the through hole 15e is formed to penetrate the conductor pattern 40 and the dielectric layer 15.

[0057] The conductor layer 70 is disposed on the inner wall surface of the through hole 15 e, on the bottom surface of the through hole 15 e, and on the conductor pattern 40 around the through hole 15 e. In this case as well, the portion of the dielectric layer 12 defined by the plurality of conductor layers 50, conductor patterns 30, and conductor patterns 40 forms the waveguide 10 c, and the portion of the dielectric layer 15 defined by the plurality of conductor layers 70, conductor patterns 40, and conductor patterns 60 forms the waveguide 10 d.

[0058] <Effects of Printed Wiring Board 300> The effects of printed wiring board 300 will be described below.

[0059] The printed wiring board 300 has a waveguide 10c in the dielectric layer 12 and a waveguide 10d in the dielectric layer 15. Therefore, in the printed wiring board 300, the propagation path of the electromagnetic wave can be provided three-dimensionally within the laminate 10, further improving the degree of freedom in designing the propagation path of the electromagnetic wave.

[0060] The embodiments disclosed herein are illustrative in all respects and should not be considered limiting. The scope of the present invention is defined by the claims, not by the above-described embodiments, and is intended to include all modifications within the meaning and scope of the claims.

[0061] 10 laminate, 10a first surface, 10b second surface, 10c, 10d waveguide, 11 dielectric layer, 12 dielectric layer, 12a, 12b main surface, 12c through hole, 12d fluororesin layer, 13 dielectric layer, 13a adhesive layer, 13b fluororesin layer, 13c, 13d main surface, 14 dielectric layer, 14a, 14b main surface, 15 dielectric layer, 15a, 15b main surface, 15c adhesive layer, 15d fluororesin layer, 15e through hole, 20 conductor pattern, 21 antenna, 22 wiring, 30 conductor pattern, 30a opening, 40 conductor pattern, 40a opening, 50 conductor layer, 60 conductor pattern, 60a opening, 70 conductor layer, 100, 100A printed wiring board, 200 Base material, 200a, 200b main surfaces, 200c waveguide, 210 IC, 300 printed wiring board, DR direction, S1 preparation step, S2 patterning step, S3 hole drilling step, S4 conductor layer forming step, S5 dielectric layer attachment step, S6 patterning step.

Claims

1. A printed wiring board comprising: a laminate; and a first conductor pattern, wherein the laminate has a plurality of dielectric layers stacked one on the other, and has a first surface and a second surface opposite to the first surface in the stacking direction of the plurality of dielectric layers, the laminate has an incident port on the first surface, and has a first waveguide inside the laminate connected to the incident port, and the first conductor pattern has an antenna disposed on the second surface, and radiates electromagnetic waves that are incident from the incident port and propagate within the first waveguide.

2. The printed wiring board according to claim 1, further comprising a second conductor pattern, a third conductor pattern, and a plurality of first conductor layers, wherein the plurality of dielectric layers has a first dielectric layer located closest to the first surface, the first dielectric layer having, in the stacking direction, a first main surface forming the first surface and a second main surface opposite the first main surface, the second conductor pattern being disposed on the first main surface and having an opening forming the incident port, the third conductor pattern sandwiching the first dielectric layer between itself and the second conductor pattern, each of the plurality of first conductor layers being formed in the first dielectric layer so as to electrically connect the second conductor pattern and the third conductor pattern, and the first waveguide being a portion of the first dielectric layer defined by the second conductor pattern, the third conductor pattern, and the plurality of first conductor layers.

3. The printed wiring board according to claim 2, wherein the plurality of dielectric layers includes a second dielectric layer located closest to the second surface, the second dielectric layer being disposed on the second main surface, and the first conductor pattern being disposed on the second dielectric layer.

4. The printed wiring board according to claim 3, wherein the first dielectric layer is a first fluororesin layer, and the second dielectric layer is a first adhesive layer and a second fluororesin layer disposed on the first adhesive layer.

5. The printed wiring board according to claim 3, wherein the first dielectric layer is a first fluororesin layer and a first adhesive layer disposed on the first fluororesin layer, and the second dielectric layer is a second fluororesin layer.

6. The printed wiring board according to claim 4 or 5, wherein the difference between the dielectric constant of the first fluororesin layer and the dielectric constant of the first adhesive layer is 0.2 or less.

7. A printed wiring board according to claim 4 or 5, wherein the difference between the dielectric loss tangent of said first fluororesin layer and the dielectric loss tangent of said first adhesive layer is 0.005 or less.

8. The printed wiring board according to claim 2, further comprising: a fourth conductor pattern; and a plurality of second conductor layers, wherein the laminate has a second waveguide connected to the first waveguide inside the laminate, the plurality of dielectric layers further having a second dielectric layer, the second dielectric layer being disposed on the second main surface, the fourth conductor pattern sandwiching the second dielectric layer between itself and the third conductor pattern, each of the plurality of second conductor layers being formed within the second dielectric layer so as to electrically connect the third conductor pattern and the fourth conductor pattern, and the second waveguide being a portion of the second dielectric layer defined by the third conductor pattern, the fourth conductor pattern, and the plurality of second conductor layers.

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