An interlayer radio frequency transmission structure
By setting isolation trenches and metal pillars in the multilayer dielectric substrate and metal layer, the problem of parasitic effects and large insertion loss in the high-frequency band of the RF vertical interconnect structure is solved, realizing low-loss RF microwave signal transmission, which is suitable for three-dimensional integrated packaging.
Patent Information
- Application Number
- CN202411634451.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-15
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2044-11-15
AI Technical Summary
Existing RF vertical interconnect structures suffer from parasitic effects and high insertion loss at high frequencies, leading to degraded RF performance in three-dimensional integrated packaging and complex design and fabrication.
An interlayer radio frequency transmission structure is adopted, including multiple dielectric substrates and metal layers. By setting isolation trenches and metal pillars, a capacitance effect and resonant structure are formed. Combined with a CPW structure, the distributed capacitance and spacing are adjusted to achieve low-loss transmission.
It achieves low-loss interlayer transmission of radio frequency and microwave signals, has a simple structure that is easy to integrate, has small parasitic effects, good electrical performance, and is suitable for millimeter wave and microwave frequency bands.
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Figure CN119674483B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the field of microwave radio frequency technology, and particularly relates to an interlayer radio frequency transmission structure. BACKGROUND
[0002] With the rapid development of modern microwave electronic technology in the fields of communication and navigation, the traditional two-dimensional packaging based on planar layout cannot meet the requirements of consumers on product volume, weight and power consumption and the like. Therefore, under the existing process conditions, three-dimensional integrated packaging is usually performed on products to solve such problems.
[0003] When three-dimensional integrated packaging is performed in the radio frequency field, the key structure is an interlayer radio frequency transmission structure. However, due to the existence of parasitic effects in the radio frequency field, the use of vertical interconnection structures in the radio frequency field is mainly concentrated in the Ku frequency band and below, and is seldom used in the Ka frequency band and above.
[0004] Most of the existing radio frequency vertical interconnection structures include direct LTCC vertical vias, pin bumps and silicon vias, and coaxial form ground holes are arranged around the vias. However, the pin bump structure has large volume and insertion loss; the silicon via is limited by the current process, and the parasitic effect in the radio frequency band is obvious, which is not conducive to direct use in the field of millimeter wave three-dimensional integration; the coaxial form ground holes arranged around the vias make the design and processing more complex. In addition, the metal holes arranged in the vertical direction between different substrate layers mainly present capacitive effect in the high frequency state, which will deteriorate the radio frequency performance. SUMMARY
[0005] The application provides an interlayer radio frequency transmission structure, which can realize low-loss interlayer transmission of radio frequency microwave signals.
[0006] The application achieves the above-mentioned purpose by the following technical scheme.
[0007] The interlayer radio frequency transmission structure comprises, from bottom to top, a first dielectric substrate layer, a first metal layer, a second dielectric substrate layer, a second metal layer, a third dielectric substrate layer, a third metal layer and a fourth dielectric substrate layer which are stacked in sequence, and the first metal layer, the second metal layer and the third metal layer are grounded.
[0008] A first radio frequency port transmission line is arranged between the first dielectric substrate layer and the second dielectric substrate layer, and a second radio frequency port transmission line is arranged between the third dielectric substrate layer and the fourth dielectric substrate layer.
[0009] The first metal layer is provided with a first strip-shaped isolation groove and a first fan-shaped isolation groove which are communicated with each other, and the first radio frequency port transmission line is arranged in the first strip-shaped isolation groove in an interval manner; the second metal layer is provided with an isolation hole; the third metal layer is provided with a second strip-shaped isolation groove and a second fan-shaped isolation groove which are communicated with each other, and the second radio frequency port transmission line is arranged in the second strip-shaped isolation groove in an interval manner;
[0010] The first fan-shaped isolation groove, the second dielectric substrate layer, the isolation hole, the third dielectric substrate layer and the second fan-shaped isolation groove are provided with a metal column for transmitting signals in a vertical direction, the first fan-shaped isolation groove, the isolation hole and the second fan-shaped isolation groove are arranged in an interval manner with the metal column, and the first radio frequency port transmission line and the second radio frequency port transmission line are connected with the metal column;
[0011] The first dielectric substrate layer is detachably connected with a metal strip for adjusting a resonance frequency.
[0012] In an embodiment, the first dielectric substrate layer, the first metal layer, the second dielectric substrate layer, the second metal layer, the third dielectric substrate layer, the third metal layer and the fourth dielectric substrate layer are vertically provided with a plurality of vias for grounding.
[0013] The beneficial effect of the above technical solution is that the first metal layer, the second metal layer and the third metal layer realize grounding through the plurality of vias.
[0014] In an embodiment, the horizontal positions of the plurality of vias on the first dielectric substrate layer, the first metal layer, the second dielectric substrate layer, the second metal layer, the third dielectric substrate layer, the third metal layer and the fourth dielectric substrate layer are matched with each other.
[0015] The beneficial effect of the above technical solution is that the horizontal positions of the plurality of vias on the first dielectric substrate layer, the first metal layer, the second dielectric substrate layer, the second metal layer, the third dielectric substrate layer, the third metal layer and the fourth dielectric substrate layer are matched with each other, so that when a vertical hole is opened each time, the first dielectric substrate layer, the first metal layer, the second dielectric substrate layer, the second metal layer, the third dielectric substrate layer, the third metal layer and the fourth dielectric substrate layer are all provided with vias, thereby facilitating rapid processing of the vias.
[0016] In an embodiment, the diameters of the first fan-shaped isolation groove, the isolation hole and the second fan-shaped isolation groove are all greater than the diameter of the metal column.
[0017] The beneficial effect of the above technical solution is that the diameters of the first fan-shaped isolation groove, the isolation hole and the second fan-shaped isolation groove are all greater than the diameter of the metal column, so that the diameters of the first fan-shaped isolation groove, the isolation hole and the second fan-shaped isolation groove are arranged in an interval manner.
[0018] In one embodiment, the axes of the first fan-shaped isolation groove, the isolation hole and the second fan-shaped isolation groove are all coincident with the axis of the metal column.
[0019] In one embodiment, the width of the first strip-shaped isolation groove is greater than the width of the first radio frequency port transmission line, and the width of the second strip-shaped isolation groove is greater than the width of the second radio frequency port transmission line.
[0020] The beneficial effects of the above technical solutions are that the width of the first strip-shaped isolation groove is greater than the width of the first radio frequency port transmission line, so that the first strip-shaped isolation groove is arranged apart from the first radio frequency port transmission line; and the width of the second strip-shaped isolation groove is greater than the width of the second radio frequency port transmission line, so that the second strip-shaped isolation groove is arranged apart from the second radio frequency port transmission line.
[0021] In one embodiment, the symmetry plane of the first strip-shaped isolation groove is coincident with the symmetry plane of the first radio frequency port transmission line, and the symmetry plane of the second strip-shaped isolation groove is coincident with the symmetry plane of the second radio frequency port transmission line.
[0022] In one embodiment, the metal strip is connected with the first radio frequency port transmission line through a gold wire.
[0023] The beneficial effects of the above technical solutions are that the first radio frequency port transmission line can be connected with different metal strips mounted on the first dielectric substrate layer through a gold wire, so as to facilitate adjustment of the resonant frequency.
[0024] In one embodiment, the first dielectric substrate layer is detachably connected with a plurality of metal strips.
[0025] In one embodiment, the upper end of the fourth dielectric substrate layer is provided with a fourth metal layer.
[0026] The beneficial effects of the present application are that:
[0027] The first metal layer with the first fan-shaped isolation groove and the third metal layer with the second fan-shaped isolation groove are arranged around the metal column to form a capacitive effect, the value of the distributed capacitance can be adjusted by changing the central angle of the first fan-shaped isolation groove and the second fan-shaped isolation groove, and the capacitive effect can form a resonant structure with the inductive effect formed by the metal column, thereby avoiding the problem of excessive space occupation of the traditional coaxial structure in the four ground through holes, and facilitating the miniaturization of the interlayer transmission structure.
[0028] In addition, the first strip isolation groove is spaced apart from the first RF port transmission line to form a CPW structure, and the second strip isolation groove is spaced apart from the second RF port transmission line to form a CPW structure. The RF transmission performance can be adjusted by adjusting the spacing between the first strip isolation groove and the first RF port transmission line or by adjusting the spacing between the second strip isolation groove and the second RF port transmission line. Furthermore, the resonant frequency can be changed by replacing different metal strips, which helps to improve the RF transmission performance and thus achieve low-loss interlayer transmission of RF microwave signals. Attached Figure Description
[0029] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.
[0030] Figure 1 A schematic diagram of the structure of the present invention is shown;
[0031] Figure 2 This diagram shows the mounting schematic of the upper end of the first dielectric substrate layer in this invention;
[0032] Figure 3 This diagram shows the mounting schematic of the upper end of the third dielectric substrate layer in this invention;
[0033] Figure 4 The simulation curves of the S-parameters of the present invention are shown;
[0034] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not to scale.
[0035] Figure label:
[0036] 1-First dielectric substrate layer, 2-First RF port transmission line, 3-First metal layer, 301-First sector-shaped isolation trench, 302-First strip-shaped isolation trench, 4-Second dielectric substrate layer, 5-Second metal layer, 6-Third dielectric substrate layer, 7-Third metal layer, 701-Second sector-shaped isolation trench, 702-Second strip-shaped isolation trench, 8-Fourth dielectric substrate layer, 9-Fourth metal layer, 10-Metal pillar, 11-Second RF port transmission line, 12-Metal strip, 13-Via. Detailed Implementation
[0037] The invention will now be further described with reference to the accompanying drawings.
[0038] This invention provides an interlayer radio frequency transmission structure, such as Figure 1 As shown, it includes a first dielectric substrate layer 1, a first metal layer, a second dielectric substrate layer 4, a second metal layer 5, a third dielectric substrate layer 6, a third metal layer and a fourth dielectric substrate layer 8 stacked sequentially from bottom to top, with the first metal layer 3, the second metal layer 5 and the third metal layer 7 grounded.
[0039] A first radio frequency port transmission line 2 is provided between the first dielectric substrate layer 1 and the second dielectric substrate layer 4, and a second radio frequency port transmission line 11 is provided between the third dielectric substrate layer 6 and the fourth dielectric substrate layer 8.
[0040] like Figure 2 As shown, the first metal layer 3 has a first strip-shaped isolation groove 302 and a first sector-shaped isolation groove 301 that are interconnected, and the first radio frequency port transmission lines 2 are spaced apart in the first strip-shaped isolation groove 302; the second metal layer 5 has isolation holes; as shown Figure 3 As shown, the third metal layer 7 is provided with a second strip-shaped isolation groove 702 and a second sector-shaped isolation groove 701 that are interconnected, and the second radio frequency port transmission line 11 is spaced out in the second strip-shaped isolation groove 702;
[0041] Metal pillars 10 for signal transmission are vertically disposed in the first sector-shaped isolation groove 301, the second dielectric substrate layer 4, the isolation hole, the third dielectric substrate layer 6, and the second sector-shaped isolation groove 701. The first sector-shaped isolation groove 301, the isolation hole, and the second sector-shaped isolation groove 701 are all spaced apart from the metal pillars 10. The first radio frequency port transmission line 2 and the second radio frequency port transmission line 11 are both connected to the metal pillars 10.
[0042] like Figure 2 As shown, a metal strip 12 for adjusting the resonant frequency is detachably connected to the first dielectric substrate layer 1.
[0043] It is understandable that by setting a first metal layer 3 with a first sector-shaped isolation groove 301 and a third metal layer 7 with a second sector-shaped isolation groove 701 around the metal pillar 10, a capacitance effect is formed. The value of the distributed capacitance can be adjusted by changing the size of the central angle of the first sector-shaped isolation groove 301 and the second sector-shaped isolation groove 701, and a resonant structure can be formed with the inductive effect of the metal pillar 10. This avoids the problem of the traditional coaxial structure occupying too much space by drilling grounding holes around the perimeter, and thus is conducive to the miniaturization of the interlayer transmission structure.
[0044] In addition, the first strip isolation groove 302 is spaced apart from the first RF port transmission line 2 to form a CPW structure, and the second strip isolation groove 702 is spaced apart from the second RF port transmission line 11 to form a CPW structure. The RF transmission performance can be adjusted by adjusting the spacing between the first strip isolation groove 302 and the first RF port transmission line 2 or by adjusting the spacing between the second strip isolation groove 702 and the second RF port transmission line 11. Furthermore, the resonant frequency can be changed by replacing different metal strips 12, which is beneficial to improving the RF transmission performance and thus realizing low-loss interlayer transmission of RF microwave signals.
[0045] It should be noted that the length of the metal strip 12 can be related to the working wavelength, such as the length of the metal strip 12 can be one quarter of the working wavelength; the first dielectric substrate layer 1, the second dielectric substrate layer 4, the third dielectric substrate layer 6 and the fourth dielectric substrate layer 8 can be the same kind of medium, such as all using Rogers5880 medium substrate, the dielectric constant is 2.2, the thickness is 0.254mm-0.508mm, the loss tangent is 0.0009, or it can be a combination of different medium layers; in addition, the interlayer radio frequency transmission structure can be used in millimeter wave and microwave and other radio frequency fields.
[0046] In one embodiment, a plurality of vias 13 for grounding are vertically arranged on the first dielectric substrate layer 1, the first metal layer 3, the second dielectric substrate layer 4, the second metal layer 5, the third dielectric substrate layer 6, the third metal layer 7 and the fourth dielectric substrate layer 8.
[0047] It can be understood that the first metal layer 3, the second metal layer 5 and the third metal layer 7 are grounded through a plurality of vias 13.
[0048] In one embodiment, the horizontal positions of the plurality of vias 13 on the first dielectric substrate layer 1, the first metal layer 3, the second dielectric substrate layer 4, the second metal layer 5, the third dielectric substrate layer 6, the third metal layer 7 and the fourth dielectric substrate layer 8 are matched with each other.
[0049] It can be understood that the horizontal positions of the plurality of vias 13 on the first dielectric substrate layer 1, the first metal layer 3, the second dielectric substrate layer 4, the second metal layer 5, the third dielectric substrate layer 6, the third metal layer 7 and the fourth dielectric substrate layer 8 are matched with each other, so that each time a vertical hole is opened, the first dielectric substrate layer 1, the first metal layer 3, the second dielectric substrate layer 4, the second metal layer 5, the third dielectric substrate layer 6, the third metal layer 7 and the fourth dielectric substrate layer 8 are provided with vias 13, thereby facilitating the rapid processing of the vias 13.
[0050] It should be noted that the plurality of vias 13 on the first dielectric substrate layer 1 are symmetrically arranged on the first dielectric substrate layer 1, and the axis of the metal column 10 is located on the symmetry plane of the first dielectric substrate layer 1.
[0051] In one embodiment, the diameters of the first fan-shaped isolation groove 301, the isolation hole and the second fan-shaped isolation groove 701 are greater than the diameter of the metal column 10.
[0052] It can be understood that the diameters of the first fan-shaped isolation groove 301, the isolation hole and the second fan-shaped isolation groove 701 are greater than the diameter of the metal column 10, so that the diameters of the first fan-shaped isolation groove 301, the isolation hole and the second fan-shaped isolation groove 701 are arranged at intervals.
[0053] In one embodiment, the axes of the first sector-shaped isolation groove 301, the isolation hole and the second sector-shaped isolation groove 701 all coincide with the axis of the metal column 10.
[0054] In one embodiment, the width of the first strip-shaped isolation groove 302 is greater than the width of the first radio frequency port transmission line 2, and the width of the second strip-shaped isolation groove 702 is greater than the width of the second radio frequency port transmission line 11.
[0055] It can be understood that the width of the first strip-shaped isolation groove 302 is greater than the width of the first radio frequency port transmission line 2, so that the first strip-shaped isolation groove 302 is arranged apart from the first radio frequency port transmission line 2; the width of the second strip-shaped isolation groove 702 is greater than the width of the second radio frequency port transmission line 11, so that the second strip-shaped isolation groove 702 is arranged apart from the second radio frequency port transmission line 11.
[0056] In one embodiment, the symmetry plane of the first strip-shaped isolation groove 302 coincides with the symmetry plane of the first radio frequency port transmission line 2, and the symmetry plane of the second strip-shaped isolation groove 702 coincides with the symmetry plane of the second radio frequency port transmission line 11.
[0057] In one embodiment, the metal strip 12 is connected with the first radio frequency port transmission line 2 through a gold wire.
[0058] It can be understood that the first radio frequency port transmission line 2 can be connected with different metal strips 12 mounted on the first dielectric substrate layer 1 through gold wires, so as to facilitate adjustment of the resonant frequency.
[0059] In one embodiment, the first dielectric substrate layer 1 is detachably connected with a plurality of metal strips 12.
[0060] It should be noted that the metal strip 12 is located on the side of the first radio frequency port transmission line 2, and it is not covered by the second dielectric substrate.
[0061] In one embodiment, the upper end of the fourth dielectric substrate layer 8 is provided with a fourth metal layer 9.
[0062] The present application gives a specific example of an interlayer radio frequency transmission structure. Among them, the first dielectric substrate layer 1, the second dielectric substrate layer 4, the third dielectric substrate layer 6 and the fourth dielectric substrate layer 8 all adopt the dielectric substrate of Rogers 5880, whose dielectric constant is 2.2, the thickness is 0.254mm, and the loss tangent is 0.0009; the length of the metal strip 12 is one quarter of the working wavelength; the port impedance of the first radio frequency port transmission line 2 and the second radio frequency port transmission line 11 is 50Ω, and the included angle between the two ports is 180°. In addition, the present application uses HFSS simulation to obtain the S parameter simulation curve of the specific example as shown in Figure 4
[0063] In conclusion, the interlayer radio frequency transmission structure in the application has simple structure, is easy to integrate, has convenient parasitic effect adjustment, small dispersion effect and good electrical performance.
[0064] In the description of the present application, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "back", "inner", "outer", "left", "right" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.
[0065] Although the present application is described herein with reference to particular embodiments, it is to be understood that these examples are merely illustrative of the principles and applications of the present application. It should therefore be understood that numerous modifications can be made to the illustrative embodiments and that other arrangements can be devised without departing from the spirit and scope of the present application as defined by the appended claims. It should be understood that the different dependent claims and features described herein can be combined with each other in different ways than the original claims describe. It should also be understood that features described in relation to one embodiment can be used in other described embodiments.
Claims
1. An interlayer radio frequency transmission structure, characterized in that, It includes a first dielectric substrate layer (1), a first metal layer (3), a second dielectric substrate layer (4), a second metal layer (5), a third dielectric substrate layer (6), a third metal layer (7), and a fourth dielectric substrate layer (8) stacked sequentially from bottom to top, wherein the first metal layer (3), the second metal layer (5), and the third metal layer (7) are grounded; A first radio frequency port transmission line (2) is provided between the first dielectric substrate layer (1) and the second dielectric substrate layer (4), and a second radio frequency port transmission line (11) is provided between the third dielectric substrate layer (6) and the fourth dielectric substrate layer (8). The first metal layer (3) is provided with a first strip-shaped isolation groove (302) and a first sector-shaped isolation groove (301) that are interconnected, and the first radio frequency port transmission lines (2) are spaced apart in the first strip-shaped isolation groove (302); the second metal layer (5) is provided with isolation holes; the third metal layer (7) is provided with a second strip-shaped isolation groove (702) and a second sector-shaped isolation groove (701) that are interconnected, and the second radio frequency port transmission lines (11) are spaced apart in the second strip-shaped isolation groove (702); Metal pillars (10) for transmitting signals are vertically disposed in the first sector-shaped isolation groove (301), the second dielectric substrate layer (4), the isolation hole, the third dielectric substrate layer (6), and the second sector-shaped isolation groove (701). The first sector-shaped isolation groove (301), the isolation hole, and the second sector-shaped isolation groove (701) are all spaced apart from the metal pillars (10). The first radio frequency port transmission line (2) and the second radio frequency port transmission line (11) are both connected to the metal pillars (10). A metal strip (12) for adjusting the resonant frequency is detachably connected to the first dielectric substrate layer (1); The metal strip (12) is connected to the first radio frequency port transmission line (2) via gold wire.
2. The interlayer radio frequency transmission structure according to claim 1, characterized in that, The first dielectric substrate layer (1), the first metal layer (3), the second dielectric substrate layer (4), the second metal layer (5), the third dielectric substrate layer (6), the third metal layer (7), and the fourth dielectric substrate layer (8) are all vertically provided with a plurality of vias (13) for grounding.
3. The interlayer radio frequency transmission structure according to claim 2, characterized in that, The horizontal positions of a plurality of vias (13) on the first dielectric substrate layer (1), the first metal layer (3), the second dielectric substrate layer (4), the second metal layer (5), the third dielectric substrate layer (6), the third metal layer (7), and the fourth dielectric substrate layer (8) are all matched with each other.
4. The interlayer radio frequency transmission structure according to claim 1, characterized in that, The diameters of the first sector-shaped isolation groove (301), the isolation hole, and the second sector-shaped isolation groove (701) are all larger than the diameter of the metal column (10).
5. The interlayer radio frequency transmission structure according to claim 4, characterized in that, The axes of the first sector-shaped isolation groove (301), the isolation hole and the second sector-shaped isolation groove (701) all coincide with the axis of the metal column (10).
6. The interlayer radio frequency transmission structure according to claim 1, characterized in that, The width of the first strip isolation groove (302) is greater than the width of the first radio frequency port transmission line (2), and the width of the second strip isolation groove (702) is greater than the width of the second radio frequency port transmission line (11).
7. The interlayer radio frequency transmission structure according to claim 6, characterized in that, The plane of symmetry of the first strip isolation groove (302) coincides with the plane of symmetry of the first radio frequency port transmission line (2), and the plane of symmetry of the second strip isolation groove (702) coincides with the plane of symmetry of the second radio frequency port transmission line (11).
8. The interlayer radio frequency transmission structure according to claim 1, characterized in that, A plurality of the metal strips (12) are detachably connected to the first dielectric substrate layer (1).
9. The interlayer radio frequency transmission structure according to claim 1, characterized in that, A fourth metal layer (9) is provided at the upper end of the fourth dielectric substrate layer (8).
Citation Information
Patent Citations
Frequency-adjustable microstrip filter device
CN221552126U