Wireless System Package

Abstract

A device (100) having a substrate (104), the substrate including opposing first and second surfaces (124) and (126), the first surface including a metal pad (128), a dielectric layer between the first and second surfaces, and an opening (134) extending through the dielectric layer and connecting between the first and second surfaces, the opening including a first raised structure and a second raised structure, each of the first raised structure and the second raised structure extending with a uniform cross-section along the opening.

Description

[Technical field]

[0001] The wireless system may include an integrated circuit and an antenna. The integrated circuit may transmit or receive radio signals via the antenna. The wireless system may also include a waveguide coupled between the integrated circuit and the antenna to transmit the radio signals. If the wireless system transmits / receives radio signals of multiple frequency bands / channels, the wireless system may include multiple antennas for transmitting / receiving radio signals of multiple frequency bands / channels or to separate received and transmitted radio signals. The wireless system may also include multiple waveguides coupled between the integrated circuit and the multiple antennas. Different waveguides may be isolated from each other to reduce cross-coupling of radio signals between the waveguides. However, the degree of isolation may be limited by various factors, such as the form factor of the wireless system. Summary of the Invention

[0002] In one example, there is a device that includes a substrate having first and second opposing surfaces, the first surface including a metal pad, a dielectric layer between the first and second surfaces, and an opening extending through the dielectric layer and connecting between the first and second surfaces, the opening including first and second raised structures, each of the first and second raised structures extending with a uniform cross-section along the opening.

[0003] In another example, there is a device that includes a substrate having first and second opposing surfaces, the first surface including metal pads, a first metal layer on the second surface, the first metal layer including openings, a network of interconnects between the first and second surfaces and coupled to the metal pads, a dielectric layer between the first and second surfaces and surrounding the network of interconnects, the dielectric layer including a first dielectric material, a cavity in the dielectric layer extending from the opening, the cavity including a second dielectric material, and a second metal layer covering side and bottom surfaces of the cavity.

[0004] Other aspects are also described and claimed. [Brief description of the drawings]

[0005] [Figure 1A] FIG. 1 is a schematic diagram illustrating various views of an example wireless system. [Figure 1B] FIG. 1 is a schematic diagram illustrating various views of an example wireless system. [Figure 1C] FIG. 1 is a schematic diagram illustrating various views of an example wireless system.

[0006] [Figure 2A] FIG. 2 is a schematic diagram illustrating a top view of an example raised waveguide. [Figure 2B] FIG. 2 is a schematic diagram illustrating a top view of an example raised waveguide.

[0007] [Figure 2C] FIG. 2 is a schematic diagram illustrating a plan view of an example rectangular waveguide.

[0008] [Figure 2D] 5 is a graph illustrating the characteristics of the example waveguides of FIGS. 2A-2C.

[0009] [Figure 3A] FIG. 2 is a schematic diagram illustrating a plan view of an example waveguide. [Figure 3B] FIG. 2 is a schematic diagram illustrating a plan view of an example waveguide. [Figure 4A] FIG. 2 is a schematic diagram illustrating a plan view of an example waveguide. [Figure 4B] FIG. 2 is a schematic diagram illustrating a plan view of an example waveguide.

[0010] [Figure 5A] FIG. 2 is a schematic diagram illustrating a top view of an example isolation structure in contact with a waveguide. [Figure 5B] 1 is a schematic diagram illustrating a cross-sectional view of an example isolation structure in contact with a waveguide.

[0011] [Figure 6A] FIG. 2 is a schematic diagram illustrating a top view of an example isolation structure in contact with a waveguide. [Figure 6B] 1 is a schematic diagram illustrating a cross-sectional view of an example isolation structure in contact with a waveguide.

[0012] [Figure 7] FIG. 1 is a schematic diagram illustrating a cross-sectional view of an example wireless system. [Figure 8] FIG. 1 is a schematic diagram illustrating a cross-sectional view of an example wireless system. [Figure 9] FIG. 1 is a schematic diagram illustrating a cross-sectional view of an example wireless system.

[0013] [Figure 10A] 1A-1C are schematic diagrams illustrating cross-sectional views of respective example wireless systems. [Figure 10B] 1A-1C are schematic diagrams illustrating cross-sectional views of respective example wireless systems.

[0014] [Figure 11A] FIG. 1 is a schematic diagram illustrating various views of an example printed circuit board (PCB) substrate of a wireless system. [Figure 11B] FIG. 1 is a schematic diagram illustrating various views of an example printed circuit board (PCB) substrate of a wireless system. [Figure 11C] FIG. 1 is a schematic diagram illustrating various views of an example printed circuit board (PCB) substrate of a wireless system. [Figure 11D] FIG. 1 is a schematic diagram illustrating various views of an example printed circuit board (PCB) substrate of a wireless system.

[0015] [Figure 12A] 1 is a schematic diagram illustrating various views of an example 3D antenna of a wireless system. [Figure 12B] 1 is a schematic diagram illustrating various views of an example 3D antenna of a wireless system.

[0016] [Figure 13] FIG. 1 is a schematic diagram illustrating a perspective view of an example PCB board and an example 3D antenna of a wireless system.

[0017] In the drawings, the same or different reference numbers are used to denote identical or similar (structural and / or functional) features. Also, some figures include dimensional indicators indicating x, y, and z dimensions. References to these dimensions and corresponding directions (e.g., top, bottom, above, below, etc.) are intended to aid in orientation and are not necessarily limiting. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] 1A is a schematic diagram illustrating a simplified cross-sectional view of a wireless system 100, according to some examples. In some examples, the wireless system 100 may be configured to transmit and / or receive millimeter wave signals (e.g., having a frequency range of 30 GHz to 300 GHz). The wireless system 100 includes a packaged semiconductor device 102, a system substrate 104, and a 3D antenna 106, where the system substrate 104 is between and interfaces with the packaged semiconductor device 102 and the 3D antenna 106.

[0019] In some examples, the packaged semiconductor device 102, the system substrate 104, and the 3D antenna 106 may be stacked to form a launch-on-package (LoP). Specifically, the packaged semiconductor device 102 includes an integrated circuit (IC) 108 that may have both transmitting and receiving capabilities. The IC 108 may be partially or fully encapsulated, and the illustrated example includes the IC 108 on a substrate 110 that is covered with an encapsulation layer 112. The encapsulation layer 112 may include plastic, ceramic, resin, or other suitable material. The substrate 110 has a surface 114. A portion of a metal layer 115 is along the surface 114 as a patch 116 and a patch 118. Each of the patches 116 and 118 is connected to the IC 108 by a respective signal path 120 and 122, which may be formed as a combination of metal layer portions and vias, or striplines, by way of example. The signal paths 120 and 122 facilitate wave communication. For example, signal path 120 may be a transmit path along which IC 108 communicates a first electrical signal for transmission by patch 116, thus converting the mode propagating on signal path 120 to a waveguide mode. Similarly, signal path 122 may be a receive path for receiving a second electrical signal received by patch 118 and communicated to IC 108. Patch 116 may receive the first electrical signal from IC 108 via signal path 120, convert the first electrical signal to a first wireless signal, and radiate the first wireless signal. Patch 118 may receive the second wireless signal, convert the second wireless signal to a second electrical signal, and transmit the second electrical signal to IC 108 via signal path 122.

[0020] The packaged semiconductor device 102 may be mounted on a system substrate 104, which may be configured as part of a LoP. The system substrate 104 has opposing surfaces 124 and 126. The surface 124 faces the surface 114 (and / or the metal layer 115, and the patches 116 and 118) of the packaged semiconductor device 102. The system substrate 104 includes an electrically insulating material between the surfaces 124 and 126. The electrically insulating material may include a dielectric material, a fiberglass material, such as one or more layers. In some examples, the system substrate 104 may include a printed wiring board (PCB). The system substrate 104 may include various conductors or conductive regions (e.g., metal pads) on the surfaces 124 and 126 and a network of interconnects (e.g., traces, vias, etc.) coupled between some of the regions and surrounded by an electrically insulating material. The conductors and interconnects are not shown in FIG. 1A for simplicity. The packaged semiconductor device 102 may be mounted to the system substrate 104 via solder balls (or solder columns) 128, which may form part of a ball grid array (BGA).

[0021] The system substrate 104 further includes openings 130 and 132 through a thickness (e.g., in the z dimension) of the system substrate 104, which may be filled with air, extending from the surface 124 to the surface 126. The opening 130 may be aligned with the patch 116, and the opening 132 may be aligned with the patch 118. Additionally, the opening 130 has a sidewall 138, and the opening 132 has a sidewall 140, which may be metallized as described further below. The opening 130 may provide (or be part of) a waveguide 134 for transmitting wireless signals to or from the patch 116. The opening 132 may provide (or be part of) a waveguide 136 for transmitting wireless signals to or from the patch 118. In various examples, openings 130 and 132 can each have a particular uniform cross-sectional shape through the thickness of system substrate 104 between surfaces 124 and 126 .

[0022] The 3D antenna 106 may also be mounted on or to the system substrate 104. The 3D antenna 106 may have opposing surfaces 142 and 144, with the surface 142 facing the surface 126 of the system substrate 104. The 3D antenna 106 may include a structure formed, for example, by molding or 3D printing a material (e.g., plastic), and the surfaces of the 3D antenna 106, including the surfaces 142 and 144, may be metallized (or coated with a layer of metal). In some examples, the 3D antenna 106 may also be formed as a metal structure. The 3D antenna 106 may be mounted on the system substrate 104 based on various techniques, such as a screw 146 as shown in FIG. 1A. In some examples, the 3D antenna 106 may be attached to the surface 126 of the system substrate 104 by an adhesive. There may be a gap 148 (e.g., an air gap, or a gap defined by the thickness of an adhesive) between the surfaces 126 and 142. The 3D antenna 106 may also include or be mounted on additional portions that are not shown for ease of illustration and description.

[0023] The 3D antenna 106 may include apertures 150 and 152 formed through a thickness (e.g., in the z dimension) of the 3D antenna 106. Each of the apertures 150 and 152 may extend from the surface 142 to the surface 144. The aperture 150 may have a sidewall 158 that is covered with metal, and the aperture 152 may have a sidewall 160 that is covered with metal. The aperture 150 may be aligned with the aperture 130 of the system substrate 104, and the aperture 150 may provide a waveguide 154 that connects with the waveguide 134. The aperture 152 may also be aligned with the aperture 132 of the system substrate 104, and the aperture 152 may provide a waveguide 156 that connects with the waveguide 136. In various examples, the apertures 150 and 152 may each have a particular uniform cross-sectional shape through the thickness of the 3D antenna 106 between the surfaces 142 and 144. The cross-sectional shape and area of ​​aperture 150 can be matched to the cross-sectional shape and area of ​​aperture 130 to improve the continuity of the connection between waveguide 134 and waveguide 154. Also, the cross-sectional shape and area of ​​aperture 152 can be matched to the cross-sectional shape and area of ​​aperture 132 to improve the continuity of the connection between waveguide 136 and waveguide 156.

[0024] The LoP package of the wireless system 100 can provide a reduced form factor or reduced footprint by stacking the packaged semiconductor device 102, the system package 104, and the 3D antenna 106. However, the LoP package can present challenges to isolation between the waveguides 134 and 136 and between the waveguides 154 and 156. In particular, a radio signal propagating in a waveguide (e.g., the waveguide 134) can propagate through the gap 148 to an adjacent waveguide (e.g., the waveguide 136), which can contribute to cross-coupling between the waveguides. The distance / width of the gap 148 can affect the power of the radio signal propagating along the gap 148 and the degree of cross-coupling, and the distance / width can vary due to tolerances and / or specifications in the assembly of the LoP package. Also, to reduce the form factor of the LoP package, adjacent waveguides may be closer to each other, which may reduce the propagation distance of wireless signals between adjacent waveguides and further exacerbate cross-coupling.

[0025] 1B illustrates an example of a wireless system 100 from a perspective view of the metal layer 115 of FIG. 1A along the surface 114, and illustrates only a partial view so that only a single patch 116 is shown. The patch 116 may be square or rectangular and has a length I patch and width w patch For example, I patch = 0.82 mm and width w patch =0.98 mm. Metal layer 115 provides a boundary surrounding patch 116, the boundary having a dimension I border and w border For example, I border = 1.11 mm, and the width w border = 2.15 mm. The border and patch 116 are surrounded by an array of solder balls 128, illustratively five in the y dimension and four in the x dimension. The patch 116 may also generally be surrounded by ground vias 162. Finally, the signal path 120 is shown to include a stripline 164 and a via 166.

[0026] FIG. 1C illustrates an example of a wireless system 100 for providing improved isolation. Referring to FIG. 1C, the packaged semiconductor device 102 may include patches 176 and 178 in addition to patches 116 and 118. The nearest neighboring patches (and their respective waveguides with which they communicate) are separated by a distance d. Each of the patches 116, 118, 176, and 178 may transmit a radio signal having a particular polarization axis based on the orientation of the major axis (the longest symmetrically located axis) of the respective patch. For example, the major axis of patch 116 is orthogonal to the major axis of patch 118, and thus the respective signals from those patches are cross-polarized with respect to each other. In such a configuration, a radio signal propagating from one patch and one waveguide (e.g., patch 116 and waveguide 134) may have an orthogonal polarization axis as a radio signal in an adjacent patch and waveguide (e.g., patch 118 and waveguide 136). Thus, if a radio signal in one waveguide leaks into an adjacent waveguide, it may be rejected by the patch through the adjacent waveguide, reducing cross-coupling between the adjacent waveguides. However, the cross-polarized arrangement increases the spacing between the patch and the waveguide, which may increase the footprint of the wireless system 100.

[0027] FIG. 2A is a plan view of an example waveguide 200 that can promote isolation against cross-coupling of wireless signals. FIG. 2A and FIG. 2B show the same view of the waveguide 200, but with different sets of labels showing different features. In some examples, the waveguide 200 can be a waveguide 134 / 136 of the system substrate 104. In some examples, the waveguide 200 can also be a waveguide 154 / 156 of the 3D antenna 106. FIG. 2A shows a view of the cross-sectional shape of the waveguide 200 at a particular point along the thickness of the system substrate 104 or the 3D antenna 106.

[0028] 2A, the waveguide 200 may include an aperture 202, which may be created by drilling, milling, a combination of both, or even other techniques. The waveguide 200 may have a footprint having a first dimension (e.g., x-dimension) having a length L1 and a second dimension (e.g., y-dimension) having a length L2. Just as a reference and in one example, L1 may be 2.20 mm and L2 may be 1.11 mm. In different examples, the values ​​of L1 and L2 may be determined using, for example, numerical approximation or simulation (e.g., full-wave simulation). Further considerations regarding the determination of L1 and L2 are described in "Closed Forms for the Parameters of Finned and Ridged Waveguides," Wolfgang J. R. Hofer and Miles N. Burton, IEEE Transactions on Microwave Theory and Techniques, Vol. MTT-30, No. 12, December 1982, which is incorporated herein by reference in its entirety. Aperture 202 may include flat sidewalls 206, 208, 210, and 212 on each of the four sides of aperture 202. [Non-Patent Document 1] “Closed-Form Expressions for the Parameters of Finned and Ridged Waveguides” by Wolfgang JR Hoefer and Miles N. Burton, IEEE Transactions On Microwave Theory and Techniques, Vol. MTT-30, No. 12, December 1982

[0029] The waveguide 200 also includes ridges 214 and 216 that further provide a cross-sectional shape (perpendicular to the z-dimension) of the aperture 202. Each of the ridges 214 and 216 may extend along a thickness (e.g., in the z-dimension of the drawings) of the system substrate 104 or the 3D antenna 106. The ridge 214 has a width w ridge and may have a distance h from side wall 206 toward side wall 208 (e.g., in the y dimension) ridgeThe ridges 216 may extend apart from each other by a width w ridge and a distance h from side wall 208 towards side wall 206 (also in the y dimension) ridge Similar to L1 and L2 above, w ridge and h ridge The value of w can be determined, for example, by simulation and by considering the "Closed forms for parameters of finned and ridged waveguides" incorporated above. ridge = 0.5mm and h ridge = 0.2 mm. Thus, the ridges 214 and 216 can protrude inward, m void It is possible to create a restricted portion 230 (see FIG. 2B) of the aperture 202 that has a reduced length in a particular dimension (e.g., the y dimension) of m void =L2-2×(h ridge 2A , the ridge 214 may have flat surfaces 242, 244, and 246, the ridge 216 may have flat surfaces 252, 254, and 256, and the opening 202 includes only flat sidewalls.

[0030] The ridges 214 and 216 may promote isolation between adjacent waveguides by reducing the footprint of the waveguide for transmitting a particular frequency band of a wireless signal. Because the footprint of the waveguide is reduced, the separation distance between adjacent waveguides (e.g., represented by distance d in FIG. 1C) may be increased within a given footprint of the wireless system 100. The increased separation may improve isolation and reduce cross-coupling between adjacent waveguides. In some examples, the increased separation allows for a co-polarized configuration in which the long axes of each of the patches are parallel (and thus co-polarized), which may further reduce the footprint of the wireless system 100.

[0031] Specifically, referring to Figure 2D, Figure 2D shows the waveguide behavior over frequency on the horizontal axis and gamma (propagation constant) on the vertical axis, comparing such behavior for a waveguide 250 having a rectangular cross-sectional area and no ridges 214 and 216 as shown in Figure 2C with the waveguide 200 of Figures 2A and 2B. As shown in Figure 2D, the cutoff frequency f of the waveguide 250 of Figure 2C can be related to the dimensions L3 and L4 of the waveguide 250 as follows: TIFF2025515390000002.tif822 Bumps 214 and 216 allow the dimensions of waveguide 200 to be reduced relative to waveguide 250 while maintaining a similar cutoff frequency f. In one example, for similar cutoff frequencies, waveguide 250 has a footprint of L3=2.55 mm×L4=1.11 mm, and waveguide 200 has a footprint of L1=2.20 mm×L2=1.11 mm, which represents approximately a 14% reduction in footprint.

[0032] The positioning of the ridges and the number of ridges may also vary among various examples. In one example, the first ridge 214 and the second ridge 216 are positioned directly opposite one another, as FIG. 2A illustrates each of the ridges 214 and 216 positioned at the same point in the x dimension along the respective flat sidewalls 206 and 208. Also, in one example and as shown in FIG. 2A, the ridges 214 and 216 may be aligned along a centerline 218 of the aperture 202, and the cross-sectional area of ​​the aperture 202 may be symmetrical about the centerline 218. Also, in some examples, the waveguide 200 may include a single ridge (e.g., one of the ridges 214 or 216).

[0033] The dimensions of the ridges can be configured to achieve a particular set of waveguide properties, including cutoff frequency and bandwidth. As mentioned above, the lengths of L1 and L2 can set the cutoff frequency and bandwidth of the waveguide in its fundamental mode. Also, h ridge can strongly control the cutoff frequency of the fundamental mode, and therefore h ridge The larger w is, the smaller the cutoff frequency is, and vice versa.ridge h ridge It is possible to shift the cutoff frequency, although not as strongly as w ridge The value of may be inversely proportional to the cutoff frequency. void Adjusting for these other considerations, therefore, L2, h ridge , and w ridge is brought about by.

[0034] 3A and 3B are plan views of another example waveguide 300 with a ridge in the aperture 202 as a possible implementation for the example waveguide 200 of FIG. 2A / FIG. 2B, taking into account milling and drilling of the waveguide shape. FIG. 3A and 3B show the same cross-sectional view of the waveguide 300, but with a different set of labels showing different features. In some examples, the waveguide 300 can be a waveguide 134 / 136 of the system substrate 104. In some examples, the waveguide 300 can also be a waveguide 154 / 156 of the 3D antenna 106. FIG. 3A and 3B illustrate the cross-sectional shape of the waveguide 300 at a particular point along the thickness of the system substrate 104 or the 3D antenna 106.

[0035] Waveguide 300 may have a footprint of L1×L2. Waveguide 300 includes aperture 202 and ridges 214 and 216. In the example of FIG. 3, aperture 202 may have curved sidewalls 302 and 304 that define circular portions 312 and 314 of aperture 202. Ridge 214 has curved surfaces 316 and 318 extending from curved sidewalls 302 and 304, respectively, and a top surface 320 coupled between curved surfaces 316 and 318. Ridge 216 has surfaces 326 and 328 extending from curved sidewalls 302 and 304, respectively, and a top surface 330 coupled between curved surfaces 326 and 328. The ridges 214 and 216 may define a constrained portion 332 (FIG. 3B) of the opening 202 between the circular portions 312 and 314. In the example of FIGS. 3A and 3B, both of the top surfaces 320 and 330 may be flat, with each top surface having a respective width (e.g., x dimension) of w ridgeAlso, the distance between the top surface (e.g., top surface 330) and the closest parallel tangent (e.g., tangent 340) to the circular region 312 / 314 can be defined as h ridge The diameter of each of the circular regions 312 and 314 may be less than 0.5×L1. The opening 202 may be symmetrical about the centerline 218.

[0036] 4A and 4B are plan views of another example waveguide 400 having ridges 214 and 216 in the aperture 202 as a possible implementation for the example waveguide 200 of FIG. 2A / FIG. 2B, again taking into account milling and drilling of the waveguide shape. FIGS. 4A and 4B illustrate the same cross-sectional view of the waveguide 400, but with different sets of labels showing different features. FIGS. 4A and 4B illustrate the cross-sectional shape of the waveguide 400 at a particular point along the thickness of the system substrate 104 or the 3D antenna 106. In some examples, the waveguide 400 can be the waveguide 134 / 136 of the system substrate 104. In some examples, the waveguide 400 can also be the waveguide 154 / 156 of the 3D antenna 106.

[0037] 4A, the waveguide 400 may have a footprint of L1×L2. The waveguide 400 includes an aperture 202 and ridges 214 and 216. The waveguide 400 includes curved sidewalls 402, 404 and a flat sidewall 406 that defines an oval region 408 of the aperture 202. The waveguide 400 also includes curved sidewalls 412, 414 and a flat sidewall 416 that defines an oval region 418 of the aperture 202. The ridges 214 and 216 may define a constrained region 420 of the aperture 202. The ridge 214 includes a top surface 422 and the ridge 216 includes a top surface 424. If the distance between the nearest linear boundaries of the oval regions 408 and 418 is w ridge Also, the distance between the top surface (e.g., top surface 424) and the closest parallel tangent to the oval region 408 / 418 (e.g., tangent 440) may be defined as h ridge The opening 202 may be symmetrical about the centerline 218.

[0038] 5A and 5B are schematic diagrams illustrating a plan view and a cross-sectional view of an example isolation structure 500 that surrounds or is adjacent to a waveguide, such as one of the waveguides 138, 140, 154, 156, 200, 300, and 400. FIG. 5A is a plan view and FIG. 5B is a cross-sectional view. The isolation structure 500 may be part of the system substrate 104 and has a surface 502 that interfaces with the gap 148. The isolation structure 500 may include an opening 504 on the surface 502 and a cavity 506 extending from the opening 504. The cavity 506 has a bottom surface 508 and a sidewall 509. The cavity 506 or its sidewall 509 may abut the opening 510 of the waveguide. The bottom surface 508 and the sidewall 509 may be coated with a metal layer. In some examples, the cavity 506 may be filled with an electrically insulating material, such as a dielectric material.

[0039] In the example of Figures 5A and 5B, the cavity 506 may be configured as a shorting stub that traps the radio signal propagating along the gap 148 to prevent (or attenuate) cross-coupling of the radio signal between adjacent waveguides. The shorting stub may provide a propagation distance equal to an odd multiple (e.g., 1, 3, or 5) of a quarter wavelength (λ / 4) of the radio signal before it is reflected. In the example of Figures 5A and 5B, the cavity 506 may have a depth D equal to an odd multiple of λ / 4. The radio signal exiting the aperture 510 may propagate through the gap 148 and enter the cavity 506 through the aperture 504. The radio signal may propagate along a vertical direction (e.g., along the z dimension) and may be reflected at the bottom surface 508, which may be coated with a metal layer to provide a shorting termination of the stub. The reflected radio signal may overlap with the incident radio signal. The depth D of the cavity 506 may set the phase difference between the reflected and incident radio signals at an odd multiple of λ / 4. Destructive interference may occur and the radio signal may be trapped and prevented from entering adjacent waveguides, which may reduce cross-coupling between adjacent waveguides.

[0040] In some examples, the opening 504 / cavity 506 can extend along one side of the opening 510 to provide isolation between two adjacent waveguides along one direction. In some examples, referring to FIG. 5A, the opening 504 / cavity 506 can extend around the opening 510 of the waveguide, for example in the form of a trench, to provide isolation between adjacent waveguides along multiple directions. In FIGS. 5A and 5B, the opening 504 / cavity 506 can have a rectangular cross-sectional shape and the isolation structure 500 can include a trench with a rectangular outline. In FIGS. 6A and 6B, the waveguide can include ridges 214 and 216 that define the cross-sectional shape of the opening 602 and the trench provided by the opening 504 / cavity 506 can have a contour that matches the shape of the opening 602. In an alternative embodiment, the shape of the opening 504 / cavity 506 does not necessarily have to match the shape of the opening 602, as will be shown later by way of example in FIG.

[0041] The isolation structures 500 and 600 of Figures 5A-6B may be implemented as part of the system substrate 104, as part of the 3D antenna 106, or both. Figures 7, 8, and 9 show an example of a wireless system 100 including an isolation structure. With reference to Figure 7, the system substrate 104 may include a shorting stub 724 as part of the isolation structure 500 / 600, and the 3D antenna 106 may include a shorting stub 732 as part of the isolation structure 500 / 600. Both the shorting stubs 724 and 732 may include a cavity having an opening that interfaces with the gap 148. Each of the cavities of the shorting stubs 724 and 732 may have sidewalls and a bottom that are covered with metal. Each of the cavities of the shorting stubs 724 and 732 may have a depth (e.g., along the z dimension) equal to an odd multiple of λ / 4, or may otherwise provide a propagation distance equal to an odd multiple of λ / 4 for the radio signal between the aperture and the reflection location. The system substrate 104 may include a shorting stub 724 between adjacent waveguides 134 and 136 to improve isolation between the adjacent waveguides. The 3D antenna 106 may also include a shorting stub 732 between adjacent waveguides 154 and 156 to improve isolation between the adjacent waveguides. FIG. 8 illustrates another example cross-sectional view of the wireless system 100, where the system substrate 104 includes a shorting stub 724 and the 3D antenna 106 does not include a shorting stub that interfaces with the gap 148. FIG. 9 illustrates another example cross-sectional view of the wireless system 100 in which the 3D antenna 106 includes a shorting stub 732 and the system substrate 104 does not include a shorting stub that interfaces with the gap 148.

[0042] 10A and 10B are schematic diagrams illustrating a first 1000A and a second 1000B example of shorting stubs 724 and 732 of wireless system 100. Generally, the cross-section of FIG. 10A is arranged as shown in subsequent FIGS. 11A-12B, while FIG. 10B includes alternative structural options in system substrate 104. In both FIGS. 10A and 10B, examples 1000A and 1000B illustrate cross-sections of patches 116 and 118 in terms of their different respective widths (e.g., along the x-dimension), matched by different widths between apertures 130 and 132 and between apertures 158 and 160. 10A illustrates three examples of shorting stubs 724a, 724b, and 724c of the system substrate 104 that interface with the gap 148, and FIG. 10B illustrates three examples of shorting stubs 724d, 724e, and 724f of the system substrate 104 that interface with the gap 148. Each of the shorting stubs 724a, 724b, and 724c, or 724d, 724e, and 724f, may be integrated into (or may be part of) the system substrate 104. Each of the shorting stubs 724a, 724b, and 724c of FIG. 10A may extend through a portion of the thickness of the system substrate 104, and each of the shorting stubs 724d, 724e, and 724f of FIG. 10B may extend through the entire thickness of the system substrate 104. The difference between Figures 10A and 10B is that Figure 10A includes a metal layer 1001 in the system substrate 104, which metal layer 1001 defines a depth D1 of the cavity formed by each of the shorting stubs 724a, 724b, and 724c, while Figure 10B does not include such a metal layer between its outermost surfaces, and as a result, there is a depth D2 in the cavity formed by each of the shorting stubs 724d, 724e, and 724f.

[0043] In Figure 10A, each of shorting stubs 724a, 724b, and 724c may have a respective cavity 1002, 1004, and 1006 that extends between metal layer 1007 and metal layer 1001 on surface 126 of system substrate 104, and thus extends only through a partial thickness of the dielectric of system substrate 104. In Figure 10A, each of cavities 1002, 1004, and 1006 may correspond to cavity 506 in Figures 5B and 6B. Cavity 1002 may also include metal sidewalls 1008 and 1010, cavity 1004 may include metal sidewalls 1012 and 1014, and cavity 1006 may include metal sidewall 1016, although on the right side of FIG. 10A cavity 1006 includes area 1020 which is shown to exclude the metal sidewalls, although isolation (e.g., high impedance) may be provided in area 1020 by a dielectric extending in the x-dimension or by air, or metal sidewalls may be included thereon. Metal sidewalls 1008 and 1010 (or 1012 and 1014, or 1016) may extend to and bond to a metal layer 1017 on surface 124 of system substrate 104. Any of the metal sidewalls may abut the waveguide opening and become part of the waveguide sidewalls. For example, in cavity 1002, metal sidewall 1010 abuts opening 130 and may be part of sidewall 138 of waveguide 134 in Figure 1A. Metal layer 1007 also includes opening 1022 in cavity 1002. Similarly, metal layer 1007 also includes opening 1024 in cavity 1004 and opening 1026 in cavity 1006. Each of openings 1022, 1024, and 1026 interfaces with gap 148 and each faces metal layer 1001, such that each opening may correspond to opening 504 in Figures 5B and 6B.

[0044] 10B, each of the shorting stubs 724d, 724e, and 724f may have a respective cavity 1030, 1032, and 1034 that extends between the metal layer 1007 on the surface 126 of the system substrate 104 and the metal layer 1017 on the surface 124, and thus extends throughout the entire dielectric thickness of the system substrate 104. In FIG. 10B, each of the cavities 1030, 1032, and 1034 may correspond to the cavity 506 of FIGS. 5B and 6B. The cavity 1030 may also include metal sidewalls 1038 and 1040, the cavity 1032 may also include metal sidewalls 1042 and 1044, and the cavity 1034 may include a metal sidewall 1046, which may include an area 1060 that does not have (or has) a metal sidewall. Any of the metal sidewalls may abut an opening in a waveguide and may be part of a sidewall of the waveguide. For example, in cavity 1030, metal sidewall 1040 abuts opening 130 and may be part of sidewall 138 of waveguide 134 in FIG. 1A. Metal layer 1007 also includes opening 1048 in cavity 1030. Similarly, metal layer 1007 also includes opening 1050 in cavity 1032 and opening 1052 in cavity 1034. Each of openings 1048, 1050, and 1052 interfaces with gap 148 and each faces metal layer 1017, such that each opening may correspond to opening 504 in FIGS. 5 and 6.

[0045] 10A and 10B , some or all of each of cavities 1002, 1004, and 1006, or 1030, 1032, and 1034, may be filled with an electrically insulating material, such as a dielectric material, a fiberglass material, etc., and the electrically insulating material may be exposed at respective openings 1022, 1024, and 1026, or 1048, 1050, and 1052. A radio signal propagating along gap 148 may enter any of cavities 1002, 1004, and 1006, or 1030, 1032, and 1034, via respective openings 1022, 1024, 1026, or 1048, 1050, and 1052. In Fig. 10A, such an incident signal may be reflected off of metal layer 1001, which may be a short-circuit terminated, and similarly in Fig. 10B, such an incident signal may be reflected off of metal layer 1017. To enable destructive interference between the incident and reflected radio signals, the depth D1 of each of cavities 1002, 1004, and 1006, or the depth D2 of each of cavities 1038, 1040, and 1042 may be an odd multiple of λ / 4 of the radio signal. In some examples, if the depth of the thickness of system substrate 104 does not match (or approximate) an odd multiple of λ / 4 of the radio signal, metal layer 1001 of Fig. 10A may be provided on system substrate 104 to define depth D1. Thus, a radio signal propagating along the gap 148 may enter one of the cavities and be reflected by the metal layer (1001 in FIG. 10A, 1017 in FIG. 10B), which may be a short-circuit termination, allowing destructive interference between the incident radio signal and the reflected radio signal, for example, in response to the depth D1 or D2, respectively. Also, in some examples, a radio signal propagating along the gap 148 and entering the cavity through its opening may propagate towards one of the respective side walls and be reflected by the side wall as a short-circuit termination. For example, in FIG. 10A, such a signal may enter the opening 1022 of the cavity 1002 and be reflected by the side walls 1008 and 1010. As another example, in FIG. 10B, such a signal may enter the opening 1048 of the cavity 1030 and be reflected by the side walls 1038 and 1040.To allow for destructive interference between the incident and reflected radio signals, the distance between the sidewall providing the short termination (e.g., sidewall 1012) and the opening 1024 labeled W2 in FIG. 10A (or between sidewall 1042 and opening 1050 in FIG. 10B) may be an odd multiple of λ / 4 of the radio signal. In some examples, the combination of D1 and W2 or D2 and W2 may be an odd multiple of λ / 4 of the radio signal, which may allow for additional distance traveled by the radio signal before reflection.

[0046] The 3D antenna 106 may also include cavities 1070 that interface with the gaps 148 to provide the shorting stubs 732. Each cavity 1070 may have an inner surface (e.g., sidewalls and bottom surface) that is coated with a metal layer, and the cavity depth H C may be an odd multiple of λ / 4 of the radio signal propagating through the gap 148.

[0047] 11A-11D illustrate various views of a PCB substrate 1102 as an example including certain aspects introduced above. The PCB substrate 1102 may be an example of the system substrate 104 of the wireless system 100 of FIGS. 1A-10B. Specifically, FIG. 11A provides a plan view of a surface 1114 of the PCB substrate 1102 (e.g., surface 124 of the system substrate 104) that interfaces with the packaged semiconductor device 102, and FIG. 11B provides a perspective view of the PCB substrate 1102 including the surface 1114. Also, FIG. 11C provides a plan view of a surface 1116 of the PCB substrate 1102 (e.g., surface 126 of the system substrate 104) that interfaces with the 3D antenna, and FIG. 11D provides a perspective view of the PCB substrate 1102 including the surface 1116. The PCB substrate 1102 includes openings 1124, 1126, 1128, and 1130. Each of the openings 1124, 1126, 1128, and 1130 may correspond to / represent one of the openings in the system substrate described above (eg, openings 134, 136, 154, 156, 202, 510, and 602).

[0048] In the illustrated example, each of the apertures 1124, 1126, 1128, and 1130 has a pair of ridges that provide a generally figure-8 shape for each of the apertures. Also, in the illustrated example, each of the apertures 1124, 1126, 1128, and 1130 is oriented such that its long axis (the longest symmetrically located axis) is orthogonal to the long axis of the nearest (or nearest) other apertures. This orthogonal orientation may provide cross-polarization between waves traveling through one waveguide relative to waves in adjacent waveguides or respective waves, improving signal isolation between those waveguides.

[0049] 11B, the PCB substrate 1102 includes a dielectric layer 1132. A metallized layer 1134 provides the surface 1114, and the metallized layer 1134 may have a thickness ranging from 15 μm to 35 μm or more. In one example, the openings 1124, 1126, 1128, and 1130 are first formed through the entire thickness (in the z dimension) of the dielectric layer 1132, and then the upper surface 1114 is metallized, thereby producing the metallized layer 1134. Metallization is also formed (simultaneously or in separate steps and / or processes) on the sidewalls 1154, 1156, 1158, and 1160 of the respective openings 1124, 1126, 1128, and 1130. In some examples, intermediate metal layers 1152 are also formed in the x / y plane, and thus oriented parallel to the surface 1114, but at a depth (e.g., in the z dimension) within the dielectric layer 1132 or separating the dielectric layer into separate layers. The PCB substrate 1102 may also include solder balls (or solder columns) 1162 on the surface 1114. The solder balls 1162 may provide electrical connections between traces / vias in the PCB substrate 1102. The solder balls 1162 may be separated from the metallized layer 1134 by an insulating layer (e.g., solder mask), not shown.

[0050] 11C provides a plan view of a surface 1116 of the PCB substrate 1102, and FIG. 11D provides a perspective view of the PCB substrate 1102 including the surface 1116. With reference to FIGS. 11C and 11D, the PCB substrate 1102 includes an isolation structure 1170 on the surface 1116. The isolation structure 1170 may include a set of cavities / trench that border the sidewalls 1154, 1156, 1158, and 1160 of the opening, and may include a shorting stub, such as the shorting stub 724 of FIG. 10A. The set of cavities / trench of the isolation structure may be filled with the same dielectric material as the dielectric layer 1132. The surface 1116 may include metal layers 1172, 1174, 1176, 1178, and 1180, and opposing edges of the metal layers may define the openings of the cavities / trench of the isolation structure 1170. Also, metal layer 1172 may surround opening 1130, metal layer 1174 may surround opening 1126, metal layer 1176 may surround opening 1128, and metal layer 1178 may surround opening 1130. In some examples, some of the metal layers may include angled edges to create a cavity opening with a constrained portion (e.g., an opening having an hourglass shape) to improve the bandwidth of the waveguide. For example, metal layer 1172 may include angled edge 1182, metal layer 1174 may include angled edge 1184, metal layer 1176 may include angled edge 1186, and metal layer 1178 may include angled edge 1188.

[0051] 12A and 12B illustrate various views of an example 3D antenna 1202, or a portion thereof, that may be mounted on the surface 1116 of the PCB substrate 1102 of FIGS. 11A-11D. Specifically, FIG. 12A provides a plan view of the surface 1204 of the 3D antenna 1202 that interfaces with the PCB substrate 1102, and FIG. 12B provides a perspective view of the 3D antenna 1202 including the surface 1204. The 3D antenna 1202 includes apertures 1212, 1214, 1216, and 1218. Each of the apertures 1212, 1214, 1216, and 1218 may correspond to / represent one of the apertures of the 3D antenna described above (e.g., apertures 150, 152, 202, 510, and 602). The 3D antenna 1202 includes waveguides 1222, 1224, 1226, and 1228 that include respective apertures 1212, 1214, 1216, and 1218. The 3D antenna 1202 may include a metallic structure or may have a surface coated / plated with a layer of metal.

[0052] 12A and 12B, the 3D antenna 1202 includes an isolation structure 1230 associated with the surface 1204. The isolation structure 1230 may include a set of cavities / trenches that border the waveguides 1222, 1224, 1226, and 1228, and may include shorting stubs, such as the shorting stub 734 of FIGS.

[0053] FIG. 13 is a perspective view of an example of a PCB substrate 1300 and a 3D antenna 1302 that may be part of a wireless system such as the wireless system 100. In FIG. 13, the PCB substrate 1300 includes apertures 1306, 1308, 1310, and 1312, each having a pair of raised structures that provide a generally figure-8 shape for each of the apertures. Each of the apertures 1306, 1308, 1310, and 1312 is oriented in a co-polarized configuration with its long axis parallel to the long axis of its nearest (or nearest) other aperture. As mentioned above, the raised structures may reduce the footprint of each aperture (and the waveguides) and increase the separation distance between the apertures. This allows the apertures to be oriented in a co-polarized configuration, reducing the footprint of the wireless system while reducing the degradation of cross-coupling between the waveguides. The 3D antenna 1302 also includes apertures 1314, 1316, 1318, and 1320 that are oriented in a co-polarized arrangement and aligned with respective apertures 1306, 1308, 1310, and 1312. The 3D antenna 1302 also includes an isolation structure 1330 that includes a set of cavities / trenches configured as shorted stubs that border the waveguides having apertures 1306, 1308, 1310, and 1312.

[0054] In this description, the term "couple" may encompass a connection, communication, or signal path that enables a functional relationship consistent with this description. For example, if device A provides a signal to control device B to perform a certain action, (A) in a first example, device A is directly coupled to device B, or (b) in a second example, device A is indirectly coupled to device B via an intervening component C, where the intervening component C does not substantially change the functional relationship between device A and device B, such that device B is controlled by device A via a control signal provided by device A.

[0055] A device that is "configured to" perform a certain task or function may be configured (e.g., programmed and / or hardwired) at the time of manufacture by a manufacturer to perform that function and / or may be configurable (or reconfigurable) by a user after manufacture to perform that function and / or other additional or alternative functions. Such configuration may be via firmware and / or software programming of the device, via the configuration and / or layout of hardware components, via the device's interconnections, or via a combination thereof.

[0056] A circuit or device described herein as including certain components may instead be adapted to be coupled to those components to form the described circuit or device. For example, a structure described herein as including one or more semiconductor elements (such as transistors), one or more passive elements (such as resistors, capacitors, and / or inductors), and / or one or more sources (such as voltage and / or current sources) may instead include only semiconductor elements within a single physical device (e.g., a semiconductor die and / or integrated circuit (IC) package) and be adapted to be coupled to at least some of the passive elements and / or sources, either during or after manufacture, such as by an end user and / or a third party, to form the described structure.

[0057] Although certain components may be described herein as being of a particular process technology, these components may be replaced with components of other process technologies. The circuits described herein are reconfigurable to include the replaced components to provide functionality at least partially similar to that available prior to the component replacement. A component shown as a resistor generally represents any one or more elements coupled in series and / or parallel to provide the amount of impedance represented by the resistor shown, unless otherwise noted. For example, a resistor or capacitor shown and described herein as a single component may instead be multiple resistors or capacitors, respectively, coupled in series or parallel between the same two nodes as a single resistor or capacitor.

[0058] Use of the phrase "ground voltage potential" herein includes chassis ground, ground, floating ground, virtual ground, digital ground, common ground, and / or any other form of ground connection applicable or suitable to the teachings herein. Unless otherwise specified herein, "about," "approximately," or "substantially" preceding a parameter means within + / - 10% of that parameter.

[0059] Modifications may be made to the exemplary embodiments described, and other embodiments are possible, within the scope of the invention.

Claims

1. It is a device, A waveguide substrate having a first surface and a second surface facing the first surface, The metal pad on the first surface, A dielectric layer between the first surface and the second surface, A first opening extending through the dielectric layer, connecting the first surface and the second surface, A side wall surrounding the first opening, comprising a first planar side wall defining a first oval region within the first opening and a second planar side wall defining a second oval region within the first opening, Including the waveguide substrate, A device wherein the side wall defines first and second raised structures located between the first oval region and the second oval region, and each of the first and second raised structures extends along the first opening.

2. The device according to claim 1, A device in which each of the first and second raised structures extends symmetrically with respect to each other along the first opening to reach the first and second surfaces.

3. The device according to claim 1, A device in which the first raised structure is located on the first side of the first opening, and the second raised structure is located on the second side of the first opening, with the first side and the second side facing each other.

4. The device according to claim 3, A device in which the first raised structure extends along the midline of the first side, and the second raised structure extends along the midline of the second side.

5. The device according to claim 1, A device in which the first aperture is configured to be a waveguide, and the dimensions of the footprint of the first aperture are based on the cutoff frequency of the waveguide.

6. The device according to claim 1, A device further comprising an isolation structure adjacent to the first opening.

7. The device according to claim 6, A device in which the isolation structure includes a cavity opening toward the second surface.

8. The device according to claim 7, A device further comprising a metal member between the first opening and the cavity opening.

9. The device according to claim 7, A device further comprising a first dielectric material within the cavity opening.

10. The device according to claim 9, The device further includes a metal layer covering the side walls and bottom of the cavity opening.

11. The device according to claim 9, A device further comprising a metal layer facing the cavity opening.

12. The device according to claim 11, A device further comprising a second dielectric material between the metal layer and the first surface.

13. The device according to claim 7, The waveguide substrate further includes a second opening that penetrates the dielectric layer and connects the first surface and the second surface, The aforementioned device A first metal layer covering the first side wall of the first opening, the first metal layer extending along the first opening and reaching the first and second surfaces, A second metal layer covering the second side wall of the second opening, the second metal layer extending along the second opening and reaching the first and second surfaces, It further includes, A device wherein the first and second metal layers provide the side walls of the cavity opening.

14. The device according to claim 13, A third metal layer on the second surface, which joins the first metal layer to the third metal layer, A fourth metal layer on the second surface, which joins the second metal layer to the fourth metal layer, It further includes, A device in which the third metal layer and the fourth metal layer are spaced apart and define a third opening connected to the cavity opening.

15. The device according to claim 14, A device in which the third metal layer has an angled edge, and the fourth metal layer has a straight edge, and the angled edge and the straight edge are on opposite sides of the first opening.

16. The device according to claim 7, The isolation structure includes a trench structure surrounding the first opening, and the trench structure opens toward the second surface. The aforementioned device The trench structure further includes a metal layer covering the side walls and bottom, A device in which the cavity opening is part of the trench structure.

17. The device according to claim 1, A packaged semiconductor device coupled to the metal pad via an interconnect, the packaged semiconductor device comprising a signal patch facing the first opening, wherein the interconnect surrounds the first opening, An antenna attached to the second surface, Devices that further include the following.

18. The device according to claim 17, The antenna has an antenna surface facing the second surface, The aforementioned antenna, A second opening extending from the surface of the antenna, which is aligned with the first opening, A first trench structure opening toward the surface of the antenna, the first trench structure surrounding the second opening, A device that includes this.

19. The device according to claim 18, The waveguide substrate further includes a second trench structure extending toward the second surface, which surrounds the first opening. A device in which the first trench structure is aligned with the second trench structure.

20. The device according to claim 19, A device further comprising a dielectric material within the second trench structure.

21. The device according to claim 1, The waveguide substrate is a device that includes a printed circuit board (PCB).

22. It is a device, Packaged semiconductor devices and A waveguide substrate having a first surface and a second surface facing the first surface, The metal pad on the first surface, A first metal layer on the second surface, comprising a first opening, A network of interconnections between the first surface and the second surface, wherein the network of interconnections is coupled to the metal pad, A dielectric layer enclosing the interconnection network between the first surface and the second surface, comprising a first dielectric material, A second opening extending through the dielectric layer and connecting the first surface and the second surface, which is matched to the packaged semiconductor device, A cavity in the dielectric layer extending from the first opening, comprising a second dielectric material, A second metal layer covering the side surface and bottom surface of the cavity, the second metal layer joining the first metal layer, The waveguide substrate includes, A device that includes this.

23. The device according to claim 22, A device further comprising a third dielectric material between the bottom surface of the cavity and the first surface.

24. The device according to claim 22, A device in which the first dielectric material and the second dielectric material are the same dielectric material.

25. The device according to claim 22, A device in which the second opening is in contact with the cavity.

26. The device according to claim 22, A device in which the second metal layer forms the side surface and contacts the second opening.

27. The device according to claim 22, A trench structure surrounding the second opening, further comprising the trench structure opening toward the second surface, A device in which the cavity is part of the trench structure.

28. The device according to claim 22, The packaged semiconductor device includes a signal patch facing the second aperture, The aforementioned device A device further comprising an antenna attached to the second surface.

29. The device according to claim 28, The antenna has an antenna surface facing the second surface, The aforementioned antenna, A third opening extending from the surface of the antenna, which is aligned with the second opening, A first trench structure opening toward the surface of the antenna, the first trench structure surrounding the third opening, A device that includes this.

30. The device according to claim 29, The waveguide substrate further comprises a second trench structure extending toward the second surface and surrounding the second opening, the second trench structure including the cavity, A device in which the first trench structure is aligned with the second trench structure.

31. The device according to claim 22, The waveguide substrate is a device that includes a printed circuit board (PCB).

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