Slow wave and vertical interconnection structure of substrate integrated notch mirror image dielectric waveguide

Abstract

The invention provides a slow wave and vertical interconnection structure of a substrate integrated notch mirror image dielectric waveguide, which belongs to the field of microwave engineering and comprises an upper dielectric substrate and a lower dielectric substrate which are stacked from top to bottom. A first metal layer, a second metal layer and a third metal layer are arranged on the upper surface of the upper-layer dielectric substrate, between the upper-layer dielectric substrate and the lower-layer dielectric substrate and on the lower surface of the lower-layer dielectric substrate respectively, and a plurality of metalized through holes are regularly arranged in the upper-layer dielectric substrate and the lower-layer dielectric substrate respectively. The first metal layer and the third metal layer are respectively provided with a first gap, a plurality of metalized blind holes or air holes located on the inner sides of the first gaps are regularly arranged in the upper-layer dielectric substrate and the lower-layer dielectric substrate respectively, one end of the second metal layer is provided with a second gap, and electromagnetic signals are input from an input port on the side edge of the upper-layer dielectric substrate. The signal is transmitted to the upper-layer notch mirror image dielectric waveguide through the upper-layer substrate integrated waveguide, then is transmitted to the lower-layer notch mirror image dielectric waveguide through the second slot, and is transmitted to an output port at the side edge of the lower-layer dielectric substrate through the lower-layer substrate integrated waveguide; and horizontal and vertical transmission of electromagnetic energy in the multilayer dielectric substrate is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave engineering, and particularly to slow-wave and vertical interconnection structures of a substrate integrated notch image dielectric waveguide. Background Art

[0002] Integrated Dielectric Waveguide (IDW) is a new type of waveguide structure based on high dielectric constant dielectric materials, mainly used in high-frequency and millimeter-wave communication systems. Compared with traditional metal waveguides, IDW utilizes the high dielectric constant characteristics of dielectric materials to concentrate electromagnetic field energy inside the dielectric for transmission, thereby achieving low-loss and high-efficiency signal transmission. Its structure is compact and easy to integrate with planar circuits, suitable for high-density integrated circuit design. IDW has important application prospects in the fields of 5G communication, terahertz technology, photonic integrated circuits, etc., and can meet the requirements of modern communication systems for high frequency, high speed, and high integration. In addition, IDW also supports multimode transmission and flexible design freedom, providing new solutions for the development of future wireless communication and sensing technologies.

[0003] The integration degree of traditional dielectric waveguides is not high, and it is not easy to form an array to transmit signals simultaneously. The substrate integrated notch image dielectric waveguide can achieve multimode simultaneous transmission because there is a metal isolation layer in the middle. The notch image dielectric waveguide has a compact structure and is easy to integrate with planar circuits, suitable for high-density integrated circuit design. For example, the Chinese invention patent application "Substrate Integrated Notch Image Dielectric Waveguide Cross-Slot Antenna" with publication number CN119481700A can achieve planar integration and is suitable for high-density integrated circuit design. However, it is difficult for a single-layer structure to simultaneously achieve multifunctional integration such as signal transmission, power distribution, and filtering. An additional planar circuit connection is required, which will introduce parasitic effects. Therefore, for the current requirements of wireless communication integrated circuits for miniaturization and integration degree, based on the advantages of the notch image waveguide, in order to make the notch image dielectric waveguide transmission more suitable for high-density integrated circuits in current wireless communication systems and meet the requirements of contemporary technology for miniaturization and integration degree, not only planar integration is required, but also multi-layer design is needed. To achieve multi-layer design, a vertical interconnection structure is essential. However, the vertical interconnection of traditional dielectric waveguides generally relies on external coaxial connectors or vertical via arrays, which will introduce additional losses. Summary of the Invention

[0004] The technical problem to be solved by the present invention is how to achieve horizontal and vertical transmission of electromagnetic energy in a multi-layer dielectric substrate.

[0005] The present invention solves the above technical problems through the following technical solutions: a slow-wave and vertical interconnection structure of a substrate integrated notch mirror dielectric waveguide, including an upper dielectric substrate and a lower dielectric substrate stacked from top to bottom. A first metal layer, a second metal layer, and a third metal layer are respectively provided on the upper surface of the upper dielectric substrate, between the upper dielectric substrate and the lower dielectric substrate, and on the lower surface of the lower dielectric substrate. A plurality of metallized vias are regularly arranged in the upper dielectric substrate and the lower dielectric substrate respectively. First slits are respectively formed in the first metal layer and the third metal layer. A plurality of metallized blind holes or air holes located inside the first slits are regularly arranged in the upper dielectric substrate and the lower dielectric substrate respectively. A second slit is formed at one end of the second metal layer. The electromagnetic signal is input from the input port on the side of the upper dielectric substrate, transmitted to the upper notch mirror dielectric waveguide through the upper substrate integrated waveguide, then transmitted to the lower notch mirror dielectric waveguide through the second slit, and transmitted to the output port on the side of the lower dielectric substrate through the lower substrate integrated waveguide.

[0006] Beneficial effects: In the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide of the present invention, the electromagnetic signal is input from the input port on the side of the upper dielectric substrate, horizontally transmitted to the upper notch mirror dielectric waveguide through the upper substrate integrated waveguide, then vertically transmitted to the lower notch mirror dielectric waveguide through the second slit, and horizontally transmitted to the output port on the side of the lower dielectric substrate through the lower substrate integrated waveguide, realizing the horizontal and vertical transmission of electromagnetic energy in multiple dielectric substrates and achieving the substrate integration of a three-dimensional structure. In addition, the present invention applies the slow-wave principle to the notch mirror waveguide. By loading metallized blind holes inside the metallized vias, the propagation speed of electromagnetic waves in this transmission structure is slowed down, and slow-wave transmission is realized in the notch mirror waveguide, which helps to achieve the miniaturization of device integration and can meet the requirements of high integration and miniaturization of future millimeter-wave communication systems.

[0007] Preferably, the upper dielectric substrate and the lower dielectric substrate have the same shape and size, and the long sides of the upper dielectric substrate are parallel to the long sides of the lower dielectric substrate. The metallized vias inside the upper dielectric substrate and the lower dielectric substrate are symmetrically distributed with respect to the symmetry axes formed by the midpoint connection lines of the short sides of the upper dielectric substrate and the midpoint connection lines of the short sides of the lower dielectric substrate respectively.

[0008] Preferably, the distance between the metallized vias in the substrate integrated waveguide along the short side direction of the upper dielectric substrate is less than the distance between the metallized vias in the notch mirror dielectric waveguide along the short side direction of the upper dielectric substrate.

[0009] Preferably, the metallized vias in the upper dielectric substrate are connected to the first metal layer and the second metal layer to form a common ground, and the metallized vias in the lower dielectric substrate are connected to the second metal layer and the third metal layer to form a common ground.

[0010] Beneficial effects: By regularly arranging a plurality of metallized vias in the upper dielectric substrate and the lower dielectric substrate respectively, and wrapping the dielectric channels for electromagnetic signal transmission therein, the present invention realizes the function of a metal wall.

[0011] Preferably, one end of the first slot is triangular, and the triangular transition substrate integrates a waveguide and a notch mirror dielectric waveguide.

[0012] Beneficial effects: By opening a triangular slot in the first metal layer and the third metal layer, the present invention realizes the transition from SIW to a notch mirror dielectric waveguide structure.

[0013] Preferably, the edge of the first slot is located between the edge of the metallized via and the edge of the metallized blind via or the air hole.

[0014] Preferably, the second slot is a rectangular slot, and the line connecting the midpoints of the two long sides of the rectangular slot is parallel to the line connecting the midpoints of the two short sides of the upper dielectric substrate.

[0015] Beneficial effects: By opening a rectangular slot in the second metal layer, the present invention enables the electromagnetic energy transmitted in the upper layer to be effectively transmitted to the lower layer without an external structure.

[0016] Preferably, the materials of the upper dielectric substrate and the lower dielectric substrate are both Rogers 3010, with a dielectric constant of 10.2 and a loss tangent value of 0.0022.

[0017] Preferably, the first metal layer, the second metal layer and the third metal layer have the same shape, and the shape is rectangular.

[0018] Preferably, the air hole is a hexagonal air column or a cylindrical air column. Description of the Drawings

[0019] Figure 1 Schematic diagram of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 1 of the present invention;

[0020] Figure 2 Top view of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 1 of the present invention;

[0021] Figure 3 Front view of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 1 of the present invention;

[0022] Figure 4 Side view of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 1 of the present invention;

[0023] Figure 5Schematic diagram of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 2 of the present invention;

[0024] Figure 6 Top view of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 2 of the present invention;

[0025] Figure 7 |S 11 | curve graph of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 1 of the present invention;

[0026] Figure 8 Cross-sectional view of the internal magnetic field of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 1 of the present invention;

[0027] Figure 9 Cross-sectional view of the internal electric field of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided in Embodiment 1 of the present invention;

[0028] In the figure: 1 input port, 2 output port, 3 first metal layer, 4 upper dielectric substrate, 5 second metal layer, 6 lower dielectric substrate, 7 third metal layer, 8 metallized through hole, 9 metallized blind hole, 10 air hole. Detailed implementation manners

[0029] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following combines specific embodiments and refers to the accompanying drawings to clearly and completely describe the technical solutions of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] Embodiment 1

[0031] See Figure 1, this embodiment provides a slow-wave and vertical interconnection structure for a substrate integrated notch mirror dielectric waveguide, including an upper dielectric substrate 4 and a lower dielectric substrate 6 arranged in a stacked manner from top to bottom. The materials of the upper dielectric substrate 4 and the lower dielectric substrate 6 are both Rogers 3010, with a dielectric constant of 10.2 and a loss tangent value of 0.0022. Loading with a Rogers 3010 dielectric substrate with a dielectric constant of 10.2 enables applications in the millimeter-wave band. A first metal layer 3, a second metal layer 5, and a third metal layer 7 are respectively provided on the upper surface of the upper dielectric substrate 4, between the upper dielectric substrate 4 and the lower dielectric substrate 6, and on the lower surface of the lower dielectric substrate 6. The first metal layer 3, the second metal layer 5, and the third metal layer 7 have the same shape, which is rectangular, and the size of the rectangle can be designed as 10 mm × 6.23 mm. A plurality of metallized vias 8 are regularly arranged in the upper dielectric substrate 4 and the lower dielectric substrate 6 respectively, and the dielectric channels for transmitting electromagnetic signals are wrapped therein to achieve the function of metal walls. The radius of the metallized vias 8 is 0.25 mm, and they are arranged at an interval period distance. The distance between adjacent metallized vias 8 is 0.8 mm. First slots are respectively opened on the first metal layer 3 and the third metal layer 7. A plurality of metallized blind vias 9 located inside the first slots are regularly arranged in the upper dielectric substrate 4 and the lower dielectric substrate 6 respectively. The height of the metallized blind vias 9 is less than or equal to the thickness of the upper dielectric substrate 4. When the height of the metallized blind vias 9 is equal to the thickness of the upper dielectric substrate 4, the metallized blind vias 9 do not penetrate the first metal layer 3 and the second metal layer 5, which is equivalent to blind vias. Similarly, the height of the metallized blind vias 9 is less than or equal to the thickness of the lower dielectric substrate 6. When the height of the metallized blind vias 9 is equal to the thickness of the lower dielectric substrate 6, the metallized blind vias 9 do not penetrate the second metal layer 5 and the third metal layer 7, which is equivalent to blind vias. The radius of the metallized blind vias 9 is 0.1 mm, and they are arranged at an interval period distance. The distance between adjacent metallized blind vias 9 is 0.56 mm. A second slot is opened at one end of the second metal layer 5. The electromagnetic signal is input from the input port 1 on the side of the upper dielectric substrate 4, horizontally transmitted through the upper substrate integrated waveguide to the upper notch mirror dielectric waveguide, and then vertically transmitted through the second slot to the lower notch mirror dielectric waveguide. Without an external structure, the electromagnetic energy transmitted in the upper layer can be effectively transmitted to the lower layer, horizontally transmitted through the lower substrate integrated waveguide to the output port on the side of the lower dielectric substrate 6, realizing the horizontal and vertical transmission of electromagnetic energy in multiple dielectric substrates and achieving the substrate integration of a three-dimensional structure. In addition, the present invention applies the slow-wave principle to the notch mirror waveguide. By loading metallized blind vias 9 inside the metallized vias 8, the metallized blind vias 9 are symmetrically arranged along the midline of the long side of the dielectric substrate at an interval period distance to form a slow-wave and vertical interconnection structure, which promotes the propagation speed of electromagnetic waves to slow down in this transmission structure, realizing the slow-wave transmission of electromagnetic signals, and the loss result is good. Realizing slow-wave transmission in the notch mirror waveguide helps to achieve the integration and miniaturization of devices, and can meet the requirements of high integration and miniaturization of future millimeter-wave communication systems.

[0032] See Figure 2 , the upper dielectric substrate 4 and the lower dielectric substrate 6 have the same shape and size. Both the upper dielectric substrate 4 and the lower dielectric substrate 6 are rectangular, with a thickness of 1.7 mm. The long side of the upper dielectric substrate 4 is parallel to the long side of the lower dielectric substrate 6. The metallized vias 8 inside the upper dielectric substrate 4 and the lower dielectric substrate 6 are symmetrically distributed with respect to the symmetry axes formed by the midpoint connection lines of the short sides of the upper dielectric substrate 4 and the lower dielectric substrate 6 respectively.

[0033] The pitch between the metallized vias 8 along the short side direction of the upper dielectric substrate in the substrate integrated waveguide is smaller than the pitch between the metallized vias 8 along the short side direction of the upper dielectric substrate in the notch mirror dielectric waveguide.

[0034] See Figure 3 and Figure 4 , the metallized vias 8 inside the upper dielectric substrate 4 are connected to the first metal layer 3 and the second metal layer 5 to form a common ground, and the metallized vias 8 inside the lower dielectric substrate 6 are connected to the second metal layer 5 and the third metal layer 7 to form a common ground.

[0035] Continue to refer to Figure 2 , one end of the first slot is triangular, which transitions between the substrate integrated waveguide and the notch mirror dielectric waveguide. The edge of the first slot is located between the edge of the metallized via 8 and the edge of the metallized blind hole 9 or the air hole 10.

[0036] The second slot is a rectangular slot, and the midpoint connection line of the two long sides of the rectangular slot is parallel to the midpoint connection line of the two short sides of the upper dielectric substrate 4.

[0037] Embodiment 2

[0038] See Figure 5 and Figure 6 , the difference between this embodiment and Embodiment 1 is that: this embodiment uses the air hole 10 to replace the metallized blind hole 9, and the rest of the structure is the same. The air hole 10 can be a hexagonal air column or a cylindrical air column.

[0039] See Figure 8 and Figure 9 , Figure 8 The internal magnetic field cross-sectional view of the slow wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided by Embodiment 1 of the present invention, Figure 9 The internal electric field cross-sectional view of the slow wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide provided by Embodiment 1 of the present invention. In the simulation, the slow wave effect is realized by using the metallized blind hole structure, and its conductive sidewall reconstructs the surface current path to make the current density distribution uniform. At the same time, the slow wave effect phenomenon is realized, and it is easier to verify the results in the simulation. In practical applications, the use of metal blind holes has higher technical process requirements.

[0040] Adopt an air column structure. The equivalent dielectric constant of the air hole region is equivalent to 1, reducing dielectric loss. At the same time, the energy can be more concentrated in the low-loss region. Selecting a hexagonal air column is convenient for actual production, and it is also possible to change the hexagon to a cylindrical shape.

[0041] The slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide of the present invention is vertically symmetric with respect to the plane of the second metal layer as a whole. Each layer includes a transmission structure and a transition structure. Taking the upper layer as an example, the transmission structure inputs an electromagnetic signal through a substrate integrated waveguide (SIW) via an input port, and transmits the electromagnetic signal to the notch mirror dielectric waveguide structure through the transition structure. The SIW is composed of upper and lower metal layers, two rows of metallized vias, and an upper dielectric substrate. The notch mirror dielectric waveguide is composed of two rows of metallized vias, a first metal layer with a slit between the two rows of metallized vias, a second metal layer, and an upper dielectric substrate. At the same time, metallized blind holes or air holes are integrated on both sides of the internal transmission line to form a slow-wave and vertical interconnection structure. The transition structure of the present invention is a triangular slit opened on the first metal layer, transitioning from the SIW to the notch mirror dielectric waveguide structure. The structure of the present invention can achieve the horizontal and vertical transmission of electromagnetic energy in a multi-layer dielectric substrate, realize the substrate integration of a three-dimensional structure, ensure the excellent performance of the three-dimensional structure, be easily integrated with other planar microwave radio frequency circuits, and at the same time, the slow-wave and vertical interconnection structure can be used to realize the miniaturization of device integration.

[0042] Figure 7 This is the S-parameter curve graph of the slow-wave and vertical interconnection structure of the substrate integrated notch mirror dielectric waveguide of the present invention after electromagnetic simulation. The solid line is the reflection curve, and the dashed line is the transmission curve. By loading excitation probes on both sides of the input port and the output port, the transmission and reflection characteristics of this transmission structure can be obtained. It has a good transmission coefficient from 29.4 GHz to 32 GHz, the insertion loss is about 3 dB, and the reflection coefficient is less than -10 dB.

[0043] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A substrate integrated notch mirror dielectric waveguide slow wave and vertical interconnect structure, characterized in that: The invention comprises an upper dielectric substrate (4) and a lower dielectric substrate (6) which are stacked from top to bottom; a first metal layer (3), a second metal layer (5), and a third metal layer (7) are respectively provided on the upper surface of the upper dielectric substrate (4), between the upper dielectric substrate (4) and the lower dielectric substrate (6), and on the lower surface of the lower dielectric substrate (6); a plurality of metallized through holes (8) are respectively regularly arranged in the upper dielectric substrate (4) and the lower dielectric substrate (6); and a first slit is respectively provided on the first metal layer (3) and the third metal layer (7). A plurality of metalized blind holes (9) or air holes (10) located inside the first gap are regularly arranged in the upper dielectric substrate (4) and the lower dielectric substrate (6), a second gap is provided at one end of the second metal layer (5), an electromagnetic signal is input from an input port (1) on the side of the upper dielectric substrate (4), transmitted to the upper trap mirror dielectric waveguide through the upper substrate integrated waveguide, then transmitted to the lower trap mirror dielectric waveguide through the second gap, and transmitted to the output port (2) on the side of the lower dielectric substrate (6) through the lower substrate integrated waveguide.

2. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: The upper dielectric substrate (4) and the lower dielectric substrate (6) have the same shape and size, and the long side of the upper dielectric substrate (4) is parallel to the long side of the lower dielectric substrate (6). The metallized through holes (8) inside the upper dielectric substrate (4) and the lower dielectric substrate (6) are symmetrically distributed with the line connecting the midpoints of the short sides of the upper dielectric substrate (4) and the line connecting the midpoints of the short sides of the lower dielectric substrate (6) as the symmetry axis.

3. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: The spacing between the metallized through holes (8) in the substrate integrated waveguide along the short side direction of the upper dielectric substrate is smaller than the spacing between the metallized through holes (8) in the trap mirror dielectric waveguide along the short side direction of the upper dielectric substrate.

4. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: The metallized through hole (8) in the upper dielectric substrate (4) is connected to the first metal layer (3) and the second metal layer (5) to form a common ground, and the metallized through hole (8) in the lower dielectric substrate (6) is connected to the second metal layer (5) and the third metal layer (7) to form a common ground.

5. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: One end of the first slot is in the shape of a triangle, and the triangle transition substrate integrated waveguide and the notch mirror dielectric waveguide.

6. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: The edge of the first gap is located between the edge of the metallized through hole (8) and the edge of the metallized blind hole (9) or the air hole (10).

7. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: The second slit is a rectangular slit, and a line connecting the midpoints of two long sides of the rectangular slit is parallel to a line connecting the midpoints of two short sides of the upper dielectric substrate (4).

8. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: The materials of the upper dielectric substrate (4) and the lower dielectric substrate (6) are both Rogers 3010, with a dielectric constant of 10.2 and a loss tangent value of 0.0022.

9. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: The first metal layer (3), the second metal layer (5) and the third metal layer (7) have the same shape and are rectangular.

10. The slow wave and vertical interconnect structure of substrate integrated notch mirror dielectric waveguide according to claim 1, characterized in that: The air hole (10) is a hexagonal air column or a cylindrical air column.

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