Interlayer radio frequency transmission structure

Abstract

The interlayer radio frequency transmission structure comprises 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 sequentially stacked from bottom to top, and the first metal layer, the second metal layer and the third metal layer are grounded; the first metal layer is provided with a first fan-shaped isolation groove, the third metal layer is provided with a second fan-shaped isolation groove, and the first dielectric substrate layer is detachably connected with a metal strip used for adjusting resonant frequency. The radio frequency transmission performance can be adjusted by adjusting the distance between the first strip-shaped isolation groove and the first radio frequency port transmission line or the distance between the second strip-shaped isolation groove and the second radio frequency port transmission line, and the resonance frequency can be changed by replacing different metal strips, so that the radio frequency transmission performance can be improved; and thus, low-loss interlayer transmission of radio frequency microwave signals is realized.

Description

Technical Field

[0001] The invention belongs to the field of microwave radio frequency technology, and in particular relates to an interlayer radio frequency transmission structure. Background Art

[0002] With the rapid development of modern microwave electronic technology in fields such as communications and navigation, traditional two-dimensional packaging based on planar layout can no longer meet consumers' requirements for product volume, weight, power consumption and other parameters. Therefore, under existing process conditions, three-dimensional integrated packaging is often used to solve such problems.

[0003] When three-dimensional integrated packaging is performed in the RF field, the key structure is the interlayer RF transmission structure. However, due to the widespread parasitic effects in the RF field, the application of vertical interconnection structures in RF is mainly concentrated in the Ku band and below, and rarely works in the Ka band and above.

[0004] Most of the existing RF vertical interconnect structures include direct LTCC vertical vias, buttons and silicon vias, and coaxial grounding holes are opened around the vias. However, the button structure has a large volume and insertion loss; the silicon via is limited by the current process, and the parasitic effect in the RF segment is obvious, which is not conducive to direct use in the field of millimeter wave three-dimensional integration; the coaxial grounding holes opened around the vias make the design and processing more complicated. In addition, the metal holes set in the vertical direction between different substrate layers mainly show a capacitive effect in the high-frequency state, which will deteriorate the RF performance. Summary of the invention

[0005] In order to overcome the defects of the prior art, the present invention provides an interlayer radio frequency transmission structure, which can realize low-loss interlayer transmission of radio frequency microwave signals.

[0006] The object of the present invention is achieved through the following technical solutions:

[0007] An interlayer radio frequency transmission structure comprises 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 stacked in sequence from bottom to top, wherein 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 isolation groove and a first fan-shaped isolation groove that are interconnected, and the first radio frequency port transmission line is arranged in the first strip isolation groove; the second metal layer is provided with an isolation hole; the third metal layer is provided with a second strip isolation groove and a second fan-shaped isolation groove that are interconnected, and the second radio frequency port transmission line is arranged in the second strip isolation groove;

[0010] A metal column for transmitting signals is vertically arranged through 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, the first fan-shaped isolation groove, the isolation hole and the second fan-shaped isolation groove are spaced apart from the metal column, and the first RF port transmission line and the second RF port transmission line are connected to the metal column;

[0011] A metal strip for adjusting the resonance frequency is detachably connected to the first dielectric substrate layer.

[0012] In one embodiment, a plurality of via holes for grounding are vertically arranged 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.

[0013] The beneficial effect of adopting the above technical solution is that the first metal layer, the second metal layer and the third metal layer are grounded through a plurality of vias.

[0014] In one embodiment, horizontal positions of the 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 all match each other.

[0015] The beneficial effect of adopting the above technical solution is that the horizontal positions of the plurality of via holes 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 each time a vertical hole is opened, 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 via holes, which is conducive to rapid processing of via holes.

[0016] In one embodiment, the diameters of the first fan-shaped isolation trench, the isolation hole, and the second fan-shaped isolation trench are all larger than the diameter of the metal column.

[0017] The beneficial effect of adopting 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 larger 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 at intervals.

[0018] In one embodiment, the axes of the first fan-shaped isolation groove, the isolation hole, and the second fan-shaped isolation groove all coincide 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 adopting the above technical solution are: the width of the first strip isolation groove is greater than the width of the first RF port transmission line, so that the first strip isolation groove and the first RF port transmission line are spaced apart; the width of the second strip isolation groove is greater than the width of the second RF port transmission line, so that the second strip isolation groove and the second RF port transmission line are spaced apart.

[0021] In one embodiment, the symmetric plane of the first strip-shaped isolation groove coincides with the symmetric plane of the first RF port transmission line, and the symmetric plane of the second strip-shaped isolation groove coincides with the symmetric plane of the second RF port transmission line.

[0022] In one embodiment, the metal strip is connected to the first RF port transmission line via a gold wire.

[0023] The beneficial effect of adopting the above technical solution is that the first RF port transmission line can be connected to different metal strips installed on the first dielectric substrate layer through gold wires, thereby facilitating the adjustment of the resonance frequency.

[0024] In one embodiment, a plurality of metal strips are detachably connected to the first dielectric substrate layer.

[0025] In one embodiment, a fourth metal layer is disposed on the upper end of the fourth dielectric substrate layer.

[0026] The beneficial effects of the present invention are:

[0027] A first metal layer with a first fan-shaped isolation groove and a third metal layer with a second fan-shaped isolation groove are arranged on the periphery of the metal column to form a capacitance 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 a resonant structure can be formed with the inductance effect formed by the metal column, thereby avoiding the problem of excessive space occupied by grounding vias on all sides of the traditional coaxial structure, and thus facilitating the miniaturization of the interlayer transmission structure;

[0028] In addition, the first strip isolation groove and the first RF port transmission line are spaced apart to form a CPW structure, and the second strip isolation groove and the second RF port transmission line are spaced apart 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 adjusting the spacing between the second strip isolation groove and the second RF port transmission line, and the resonant frequency can be changed by replacing different metal strips, which is beneficial to improving the RF transmission performance and further realizing low-loss interlayer transmission of RF microwave signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings, wherein:

[0030] Figure 1 Shows a schematic diagram of the structure of the present invention;

[0031] Figure 2 The schematic diagram of the installation of the upper end of the first dielectric substrate layer in the present invention is shown;

[0032] Figure 3 The schematic diagram of the installation of the upper end of the third dielectric substrate layer in the present invention is shown;

[0033] Figure 4 The S parameter simulation curve diagram of the present invention is shown;

[0034] In the drawings, like reference numerals are used for like parts. The drawings are not necessarily to scale.

[0035] Reference numerals:

[0036] 1-first dielectric substrate layer, 2-first RF port transmission line, 3-first metal layer, 301-first fan-shaped isolation groove, 302-first strip-shaped isolation groove, 4-second dielectric substrate layer, 5-second metal layer, 6-third dielectric substrate layer, 7-third metal layer, 701-second fan-shaped isolation groove, 702-second strip-shaped isolation groove, 8-fourth dielectric substrate layer, 9-fourth metal layer, 10-metal column, 11-second RF port transmission line, 12-metal strip, 13-via. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with the accompanying drawings.

[0038] The present invention provides an inter-layer 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 in sequence from bottom to top, and the first metal layer 3, the second metal layer 5 and the third metal layer 7 are 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 is provided with a first strip-shaped isolation groove 302 and a first fan-shaped isolation groove 301 which are interconnected, and the first RF port transmission line 2 is arranged in the first strip-shaped isolation groove 302 at intervals; the second metal layer 5 is provided with an isolation hole; Figure 3 As shown, the third metal layer 7 is provided with a second strip-shaped isolation groove 702 and a second fan-shaped isolation groove 701 which are interconnected, and the second RF port transmission line 11 is arranged in the second strip-shaped isolation groove 702 at intervals;

[0041] A metal column 10 for transmitting signals is vertically arranged through the first fan-shaped isolation groove 301, the second dielectric substrate layer 4, the isolation hole, the third dielectric substrate layer 6 and the second fan-shaped isolation groove 701. The first fan-shaped isolation groove 301, the isolation hole and the second fan-shaped isolation groove 701 are spaced apart from the metal column 10, and the first RF port transmission line 2 and the second RF port transmission line 11 are connected to the metal column 10.

[0042] like Figure 2 As shown, a metal strip 12 for adjusting the resonance frequency is detachably connected to the first dielectric substrate layer 1 .

[0043] It can be understood that, by arranging the first metal layer 3 with the first fan-shaped isolation groove 301 and the third metal layer 7 with the second fan-shaped isolation groove 701 on the periphery of the metal column 10 to form a capacitive effect, the value of the distributed capacitance can be adjusted by changing the size of the central angle of the first fan-shaped isolation groove 301 and the second fan-shaped isolation groove 701, and a resonant structure can be formed with the inductance effect formed by the metal column 10, thereby avoiding the problem of the traditional coaxial structure having ground vias around the periphery occupying too much space, and thus facilitating the miniaturization of the interlayer transmission structure;

[0044] In addition, the first strip isolation groove 302 and the first RF port transmission line 2 are spaced apart to form a CPW structure, and the second strip isolation groove 702 and the second RF port transmission line 11 are spaced apart 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 adjusting the spacing between the second strip isolation groove 702 and the second RF port transmission line 11, and the resonant frequency can be changed by replacing different metal strips 12, which is beneficial to improving the RF transmission performance and further realizing low-loss interlayer transmission of RF microwave signals.

[0045] It should be noted that the length of the metal strip 12 may be related to the working wavelength, such as the length of the metal strip 12 may 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 may be the same dielectric, such as all using Rogers5880 dielectric substrates, which have a dielectric constant of 2.2, a thickness of 0.254mm~0.508mm, and a loss tangent of 0.0009, or a combination of different dielectric layers; in addition, this interlayer RF transmission structure can be used in RF fields such as millimeter waves and microwaves.

[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, horizontal positions of the 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 match 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, which is conducive to 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 trench 301 , the isolation hole, and the second fan-shaped isolation trench 701 are all larger than the diameter of the metal pillar 10 .

[0052] It can be understood that the diameters of the first fan-shaped isolation trench 301 , the isolation hole and the second fan-shaped isolation trench 701 are all larger than the diameter of the metal column 10 , so that the diameters of the first fan-shaped isolation trench 301 , the isolation hole and the second fan-shaped isolation trench 701 are spaced apart.

[0053] In one embodiment, the axes of the first fan-shaped isolation trench 301 , the isolation hole, and the second fan-shaped isolation trench 701 all coincide with the axis of the metal pillar 10 .

[0054] In one embodiment, the width of the first strip-shaped isolation trench 302 is greater than the width of the first RF port transmission line 2 , and the width of the second strip-shaped isolation trench 702 is greater than the width of the second RF port transmission line 11 .

[0055] It can be understood that the width of the first strip isolation groove 302 is greater than the width of the first RF port transmission line 2, so that the first strip isolation groove 302 is spaced apart from the first RF port transmission line 2; the width of the second strip isolation groove 702 is greater than the width of the second RF port transmission line 11, so that the second strip isolation groove 702 is spaced apart from the second RF port transmission line 11.

[0056] In one embodiment, the symmetric plane of the first strip-shaped isolation trench 302 coincides with the symmetric plane of the first RF port transmission line 2 , and the symmetric plane of the second strip-shaped isolation trench 702 coincides with the symmetric plane of the second RF port transmission line 11 .

[0057] In one embodiment, the metal strip 12 is connected to the first RF port transmission line 2 via a gold wire.

[0058] It is understandable that the first RF port transmission line 2 can be connected to different metal strips 12 installed on the first dielectric substrate layer 1 through gold wires, so as to facilitate the adjustment of the resonant frequency.

[0059] In one embodiment, a plurality of metal strips 12 are detachably connected to the first dielectric substrate layer 1 .

[0060] It should be noted that the metal strip 12 is located on the side of the first RF port transmission line 2 and is not covered by the second dielectric substrate.

[0061] In one embodiment, a fourth metal layer 9 is disposed on the upper end of the fourth dielectric substrate layer 8 .

[0062] The present invention provides a specific example of an interlayer RF transmission structure. 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 use Rogers 5880 dielectric substrates, whose dielectric constant is 2.2, thickness is 0.254 mm, and 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 RF port transmission line 2 and the second RF port transmission line 11 is 50Ω, and the angle between the two ports is 180°. In addition, the present invention uses HFSS simulation to obtain the following Figure 4 The S-parameter simulation curve of this specific example is shown.

[0063] In summary, the interlayer radio frequency transmission structure in the present invention has a simple structure, is easy to integrate, is convenient to adjust parasitic effects, has a small dispersion effect and has good electrical performance.

[0064] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "bottom", "top", "front", "back", "inside", "outside", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0065] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. An inter-layer radio frequency transmission structure, characterized in that: The invention comprises 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) which are stacked in sequence 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 fan-shaped isolation groove (301) which are interconnected, and the first radio frequency port transmission line (2) is arranged in the first strip-shaped isolation groove (302) at intervals; the second metal layer (5) is provided with an isolation hole; the third metal layer (7) is provided with a second strip-shaped isolation groove (702) and a second fan-shaped isolation groove (701) which are interconnected, and the second radio frequency port transmission line (11) is arranged in the second strip-shaped isolation groove (702) at intervals; A metal column (10) for transmitting signals is vertically arranged through the first fan-shaped isolation groove (301), the second dielectric substrate layer (4), the isolation hole, the third dielectric substrate layer (6) and the second fan-shaped isolation groove (701); the first fan-shaped isolation groove (301), the isolation hole and the second fan-shaped isolation groove (701) are arranged at intervals from the metal column (10); and the first radio frequency port transmission line (2) and the second radio frequency port transmission line (11) are connected to the metal column (10); A metal strip (12) for adjusting the resonance frequency is detachably connected to the first dielectric substrate layer (1).

2. The inter-layer radio frequency transmission structure according to claim 1, characterized in that: A plurality of via holes (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).

3. The inter-layer radio frequency transmission structure according to claim 2, characterized in 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) all match each other.

4. The inter-layer radio frequency transmission structure according to claim 1, characterized in that: The diameters of the first fan-shaped isolation groove (301), the isolation hole and the second fan-shaped isolation groove (701) are all greater than the diameter of the metal column (10).

5. The inter-layer radio frequency transmission structure according to claim 4, characterized in that: The axes of the first fan-shaped isolation groove (301), the isolation hole and the second fan-shaped isolation groove (701) all coincide with the axis of the metal column (10).

6. The inter-layer radio frequency transmission structure according to claim 1, characterized in 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), 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).

7. The inter-layer radio frequency transmission structure according to claim 6, characterized in that: 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).

8. The inter-layer radio frequency transmission structure according to claim 1, characterized in that: The metal strip (12) is connected to the first radio frequency port transmission line (2) via a gold wire.

9. The inter-layer 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).

10. The inter-layer radio frequency transmission structure according to claim 1, characterized in that: A fourth metal layer (9) is provided on the upper end of the fourth dielectric substrate layer (8).

Images