Fully-shielded stacked radio frequency transmission line and manufacturing method thereof

Abstract

The invention provides a fully-shielded stacked radio frequency transmission line, which comprises a signal line, a first lateral shielding body, a second lateral shielding body, a first shielding line and a second shielding line, and is characterized in that the first lateral shielding body, the first shielding line, the second lateral shielding body and the second shielding line are sequentially connected end to end to form a shielding cavity; and the signal circuit is arranged in the shielding cavity. The fully-shielded stacked radio frequency transmission line provided by the invention has the advantage of high-frequency shielding. In addition, the invention also provides a manufacturing method of the fully-shielded stacked radio frequency transmission line.

Description

Technical Field

[0001] The present invention belongs to the field of circuit board manufacturing, and particularly relates to a fully shielded stacked RF transmission line and a manufacturing method thereof. Background Art

[0002] With the rapid progress of wireless communication technology, especially the popularization and application of 5G technology, the performance standards for RF transmission lines and mobile device antennas are increasing day by day. This demand is mainly reflected in two aspects: one is the requirement for high-frequency signal transmission ability, and the other is the expectation for electromagnetic shielding performance.

[0003] Aiming at frequencies in the range of up to 50 GHz and above, existing shielding methods are difficult to achieve the expected electromagnetic shielding performance in these ultra-high frequency bands, which directly affects the overall performance and signal quality of wireless communication systems. Summary of the Invention

[0004] To solve the above deficiencies of the prior art, the present application provides a fully shielded stacked RF transmission line to provide high-quality electromagnetic shielding in high-frequency transmission.

[0005] A manufacturing method of a fully shielded stacked RF transmission line includes the steps of:

[0006] Providing a core board, the core board being divided into a shielded area, a first enclosing area, and a second enclosing area, the shielded area being disposed between the first enclosing area and the second enclosing area, a signal line being provided in the shielded area, a first inner conductor being provided in the first enclosing area, and a second inner conductor being provided in the second enclosing area.

[0007] Providing a first side plate on one side of the core board, the first side plate including a first outer conductor, a second outer conductor, and a first shielding line, the first shielding line being connected between the first outer conductor and the second outer conductor, the first outer conductor corresponding to the first enclosing area, the second outer conductor corresponding to the second enclosing area, the first shielding line corresponding to the shielded area, the first outer conductor connecting to one end of the first inner conductor, and the second outer conductor connecting to one end of the second inner conductor.

[0008] A second side plate is provided on the other side of the core board. The second side plate includes a third outer conductor, a fourth outer conductor, and a second shielding circuit. The second shielding circuit is connected between the third outer conductor and the fourth outer conductor. The third conductor is arranged corresponding to the first enclosed area, the fourth outer conductor is arranged corresponding to the second enclosed area, the second shielding circuit is arranged corresponding to the shielding area, the third outer conductor is connected to the other end of the first inner conductor, and the fourth outer conductor is connected to the other end of the second inner conductor.

[0009] Remove a part of the first inner conductor, a part of the first outer conductor, and a part of the third outer conductor corresponding to the first enclosed area. The other part of the first outer conductor, the other part of the first inner conductor, and the other part of the third outer conductor are sequentially connected to form a first lateral shielding body. The two ends of the first lateral shielding body are respectively connected to one end of the first shielding circuit and one end of the second shielding circuit.

[0010] Remove a part of the second inner conductor, a part of the second outer conductor, and a part of the fourth outer conductor corresponding to the second enclosed area. The other part of the second outer conductor, the other part of the second inner conductor, and the other part of the fourth outer conductor are sequentially connected to form a second lateral shielding body. The two ends of the second lateral shielding body are respectively connected to the other end of the first shielding circuit and the other end of the second shielding circuit, thereby obtaining the fully shielded stacked RF transmission line.

[0011] In some possible embodiments, the core board further includes an inner insulating layer. The signal circuit includes a first signal circuit and a second signal circuit. The first signal circuit and the second signal circuit are respectively arranged on opposite sides of the inner insulating layer. The manufacturing method of the core board includes the steps of: providing a first slot and a second slot in the inner substrate. The inner substrate includes the inner insulating layer and a first inner copper foil layer and a second inner copper foil layer arranged on opposite sides of the inner insulating layer. Both the first slot and the second slot penetrate through the first inner copper foil layer and the inner insulating layer. Arrange the first inner conductor in the first slot, arrange the second inner conductor in the second slot, etch the first inner copper foil layer to form the first signal circuit layer, and etch the second inner copper foil layer to form the second signal circuit layer.

[0012] In some possible embodiments, the first side plate further includes a first outer insulating layer. The manufacturing method of the first side plate includes the steps of: providing a first through hole and a second through hole in the first outer substrate, where the first outer substrate includes the first outer insulating layer and a first outer copper foil layer, the first outer insulating layer is disposed between the core board and the first outer copper foil layer, and both the first through hole and the second through hole penetrate through the first outer copper foil layer and the first outer insulating layer. Disposing a first outer conductor in the first through hole, and disposing a second outer conductor in the second through hole, and etching the first outer copper foil layer to form the first shielding circuit.

[0013] In some possible embodiments, the second side plate further includes a second outer insulating layer. The manufacturing method of the second side plate includes the steps of: providing a third through hole and a fourth through hole in the second outer substrate, where the second outer substrate includes the second outer insulating layer and a second outer copper foil layer, the second outer insulating layer is disposed between the core board and the second outer copper foil layer, and both the third through hole and the fourth through hole penetrate through the second outer copper foil layer and the second outer insulating layer.

[0014] Disposing a third outer conductor in the third through hole, and disposing a fourth outer conductor in the fourth through hole, and etching the second outer copper foil layer to form the second shielding circuit.

[0015] In some possible embodiments, the method further includes the steps of: providing a first adhesive layer between one side of the core board and the first side plate, with the first outer conductor and the second outer conductor passing through the first adhesive layer; providing a second adhesive layer between the other side of the core board and the second side plate, with the third outer conductor and the fourth outer conductor passing through the second adhesive layer.

[0016] In some possible embodiments, both the first outer conductor and the third outer conductor are formed at both ends of the first inner conductor by electroplating, and both the second outer conductor and the fourth outer conductor are formed at both ends of the second inner conductor by electroplating.

[0017] In some possible embodiments, a part of the first inner conductor, a part of the first outer conductor, and a part of the third outer conductor corresponding to the first enclosed area are removed by laser etching, and a part of the second inner conductor, a part of the second outer conductor, and a part of the fourth outer conductor corresponding to the second enclosed area are removed by laser etching.

[0018] In some possible embodiments, it further includes steps of: providing a first protective layer on the first shielding line, where the first protective layer covers one end of the first lateral shielding body and one end of the second lateral shielding body; and providing a second protective layer on the second shielding line, where the second protective layer covers the other end of the first lateral shielding body and the other end of the second lateral shielding body.

[0019] In some possible embodiments, it further includes steps of: providing a third protective layer on the first lateral shielding body and providing a fourth protective layer on the second lateral shielding body.

[0020] A fully shielded stacked RF transmission line includes a signal line, a first lateral shielding body, a second lateral shielding body, a first shielding line, and a second shielding line. The first lateral shielding body, the first shielding line, the second lateral shielding body, and the second shielding line are sequentially connected end to end to form a shielding cavity, and the signal line is disposed within the shielding cavity.

[0021] The manufacturing method of the transmission line provided in this application removes part of the enclosed areas (the first enclosed area, the second enclosed area), so that the remaining part forms the lateral shielding bodies (the first lateral shielding body, the second lateral shielding body). The lateral shielding bodies are connected to the shielding lines (the first shielding line, the second shielding line) to form a shielding cavity, which can achieve omnidirectional electromagnetic shielding for the signal lines (the first signal line, the second signal line). At the same time, the shielding cavity has good structural stability, enabling the transmission line to maintain a stable expected shielding effect during both dynamic and static bending processes, thereby ensuring the overall performance and signal quality of the wireless communication system in the high-frequency band. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a cross-sectional schematic view of an inner substrate provided in an embodiment of the present application.

[0023] Figure 2 For Figure 1 It is a cross-sectional schematic view of the first inner copper foil layer of the inner substrate shown after setting the first opening.

[0024] Figure 3 For Figure 2 It is a cross-sectional schematic view of the inner insulating layer of the inner substrate shown after setting the first opening.

[0025] Figure 4 For Figure 3 It is a cross-sectional schematic view of the first inner conductor disposed within the first slot shown.

[0026] Figure 5 For etching Figure 4 It is a cross-sectional schematic view of the core board obtained after etching the first inner copper foil layer to form the first signal line shown.

[0027] Figure 6 is Figure 5 A cross-sectional schematic diagram of the core board after setting the first adhesive layer and the first outer substrate as shown.

[0028] Figure 7 is Figure 6 A cross-sectional schematic diagram of the first outer copper foil layer as shown after etching to form the first side plate.

[0029] Figure 8 is Figure 7 A cross-sectional schematic diagram of the first side plate as shown after setting the first through hole.

[0030] Figure 9 is Figure 8 A cross-sectional schematic diagram of the first via hole as shown after setting the first outer conductor.

[0031] Figure 10 is Figure 9 A cross-sectional schematic diagram of the first outer conductor as shown after setting the first protective layer.

[0032] Figure 11 is for removing Figure 9 A cross-sectional schematic diagram of the process of removing a part of the first outer conductor as shown.

[0033] Figure 12 is for removing Figure 9 A cross-sectional schematic diagram of removing a part of the first outer conductor as shown and obtaining a fully shielded stacked RF transmission line.

[0034] Description of main component symbols

[0035] Transmission line 100

[0036] Shielded area 101

[0037] First enclosed area 102

[0038] Second enclosed area 103

[0039] First inner conductor 20

[0040] Second inner conductor 21

[0041] First signal line 22

[0042] Second signal line 23

[0043] Core board 24

[0044] First adhesive layer 30

[0045] First through hole 301

[0046] Second through hole 302

[0047] Second adhesive layer 31

[0048] First outer substrate 40

[0049] First outer insulating layer 401

[0050] First outer copper foil layer 402

[0051] Second outer substrate 41

[0052] Second outer insulating layer 411

[0053] Second outer copper foil layer 412

[0054] First outer circuit layer 43

[0055] First shielding circuit 431

[0056] First side plate 432

[0057] Second outer circuit layer 44

[0058] Second shielding circuit 441

[0059] Second side plate 442

[0060] First through hole 50

[0061] Second through hole 51

[0062] First via hole 52

[0063] Second via hole 53

[0064] Third through hole 54

[0065] Fourth through hole 55

[0066] Third via hole 56

[0067] Fourth via hole 57

[0068] First outer conductor 60

[0069] Second outer conductor 61

[0070] Third outer conductor 62

[0071] Fourth outer conductor 63

[0072] First protective layer 70

[0073] Second protective layer 71

[0074] First lateral shield 80

[0075] The second lateral shielding body 81

[0076] The third protective layer 90

[0077] The fourth protective layer 91

[0078] The inner substrate 10

[0079] The inner insulating layer 11

[0080] The first opening 111

[0081] The second opening 112

[0082] The first inner copper foil layer 12

[0083] The first window 121

[0084] The second window 122

[0085] The second inner copper foil layer 13

[0086] The first slot 14

[0087] The second slot 15

[0088] The thickness direction A

[0089] The following specific embodiments will further illustrate the present application in conjunction with the above-mentioned drawings. Specific embodiments

[0090] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments.

[0091] Please refer to Figures 1 to 12 , an embodiment of the present application provides a manufacturing method of a fully shielded stacked radio frequency transmission line 100 (hereinafter referred to as the transmission line 100), including the steps:

[0092] S1: Please refer to Figure 1 , provide an inner substrate 10. The inner substrate 10 is a double-sided copper-clad substrate. The inner substrate 10 includes an inner insulating layer 11, a first inner copper foil layer 12, and a second inner copper foil layer 13. The first inner copper foil layer 12 and the second inner copper foil layer 13 are respectively disposed on opposite sides of the inner insulating layer 11. The inner substrate 10 has a thickness direction A, and along the thickness direction A, the inner substrate 10 is divided into a shielded area 101, a first enclosed area 102, and a second enclosed area 103. The shielded area 101 is connected between the first enclosed area 102 and the second enclosed area 103.

[0093] In this embodiment, the material of the inner insulating layer 11 is polyimide. In other embodiments of the present application, the material of the inner insulating layer 11 includes at least one of liquid crystal polymer (LCP), phenolic epoxy resin (EP), polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polyphenylene oxide (PPO), polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate glycol ester (PEN).

[0094] S2: Please refer to Figure 2 , and a first opening 121 and a second opening 122 are provided in the first inner copper foil layer 12. The first opening 121 is located in the first enclosing area 102. The second opening 122 is located in the second enclosing area 103. Part of the inner insulating layer 11 is respectively exposed at the bottom of the first opening 121 and at the bottom of the second opening 122. Specifically, the first opening 121 and the second opening 122 are formed by means of dry film, exposure and development, and etching. The etching solution used in this etching process is for metallic copper, and this etching solution can be ferric chloride etching solution.

[0095] S3: Please refer to Figure 3 , and a first opening 111 and a second opening 112 are provided in the inner insulating layer 11. The first opening 111 is provided corresponding to the first opening 121. The second opening 112 is provided corresponding to the second opening 122. The first opening 111 communicates with the first opening 121 to form a first slot 14. The second opening 112 communicates with the second opening 122 to form a second slot 15. Specifically, the first opening 111 and the second opening 112 are formed by means of dry film, exposure and development, and etching. The solution used in this etching process is for polyimide, and this etching solution can be hydrofluoric acid.

[0096] S4: Please refer to Figure 4, a first inner conductor 20 is disposed in the first slot 14, and a second inner conductor 21 is disposed in the second slot 15. The first inner conductor 20 is connected to the second inner copper foil layer 13. The second inner conductor 21 is connected to the second inner copper foil layer 13. The first inner conductor 20 and the second inner conductor 21 are both formed by selective electroplating of copper.

[0097] S5: Please refer to Figure 5 , etch the first inner copper foil layer 12 to form a first signal line 22, and etch the second inner copper foil layer 13 to form a second signal line 23, a first connection pad 131, and a second connection pad 132 to obtain a core board 24. Wherein, the first connection pad 131 and the second connection pad 132 are spaced apart and insulated. The second signal line 23 is disposed between the first connection pad 131 and the second connection pad 132, and the second signal line 23 is electrically insulated from the first connection pad 131 and the second connection pad 132 respectively. The first signal line 22 and the second signal line 23 are disposed opposite to each other on opposite sides of the inner insulating layer 11. The first signal line 22 and the second signal line 23 are both used to transmit electrical signals in a frequency range up to 50 GHz and above. Specifically, the first signal line 22 and the second signal line 23 are both formed through steps such as dry film, exposure and development, and etching.

[0098] S6: Please refer to Figure 6 , a first adhesive layer 30 is disposed on one side of the core board 24, and a second adhesive layer 31 is disposed on the other side of the core board 24. The first adhesive layer 30 is provided with a first through hole 301 and a second through hole 302. The first through hole 301 is disposed corresponding to the first inner conductor 20, and the second through hole 302 is disposed corresponding to the second inner conductor 21. The second adhesive layer 31 is provided with a third through hole 311 and a fourth through hole 312. The third through hole 311 is disposed corresponding to the first through hole 301, and the fourth through hole 312 is disposed corresponding to the second through hole 302.

[0099] S7: Please refer to again Figure 6 , a first outer substrate 40 is disposed on the first adhesive layer 30, and a second outer substrate 41 is disposed on the second adhesive layer 31. Wherein, the first outer substrate 40 includes a first outer insulating layer 401 and a first outer copper foil layer 402. The first outer insulating layer 401 is disposed between the first outer copper foil layer 402 and the first adhesive layer 30. The second outer substrate 41 includes a second outer insulating layer 411 and a second outer copper foil layer 412. The second outer insulating layer 411 is disposed between the second outer copper foil layer 412 and the second adhesive layer 31.

[0100] S8: Refer to Figure 7 , etch the first outer copper foil layer 402 into the first outer circuit layer 43 to obtain the first side plate 432. Etch the second outer copper foil layer 412 into the second outer circuit layer 44 to obtain the second side plate 442. Among them, in the first side plate 432, the first outer circuit layer 43 includes a first shielding circuit 431 corresponding to the shielded area 101. In the second side plate 442, the second outer circuit layer 44 includes a second shielding circuit 441 corresponding to the shielded area 101.

[0101] S9: Refer to Figure 8 , provide a first through hole 50 and a second through hole 51 in the first side plate 432. The first through hole 50 communicates with the first through hole 301 of the first adhesive layer 30 to form a first via hole 52. The second through hole 51 communicates with the second through hole 302 of the first adhesive layer 30 to form a second via hole 53. Similarly, provide a third through hole 54 and a fourth through hole 55 in the second side plate 442. The third through hole 54 communicates with the third through hole 311 of the second adhesive layer 31 to form a third via hole 56. The fourth through hole 55 communicates with the fourth through hole 312 of the second adhesive layer 31 to form a fourth via hole 57.

[0102] Among them, the first via hole 52 is provided corresponding to the third via hole 56, the first inner conductor 20 is exposed at the bottom of the first via hole 52, the first connection pad 131 is exposed at the bottom of the third via hole 56, and both the first via hole 52 and the third via hole 56 are provided corresponding to the first enclosed area 102. The second via hole 53 and the fourth via hole 57 are provided corresponding to each other, the second inner conductor 21 is exposed at the bottom of the second via hole 53, the second connection pad 132 is exposed at the bottom of the fourth via hole 57, and both the second via hole 53 and the fourth via hole 57 are provided corresponding to the second enclosed area 103.

[0103] S10: Refer to Figure 9, a first outer conductor 60 is provided on the first via 52, and a second outer conductor 61 is provided on the second via 53. The first outer conductor 60 connects one end of the first inner conductor 20 and the first shielding line 431, and the second outer conductor 61 connects the other end of the second inner conductor 21 and the first shielding line 431. A third outer conductor 62 is provided on the third via 56, and a fourth outer conductor 63 is provided on the fourth via 57. The third outer conductor 62 connects one end of the first connection pad 131 and the second shielding line 441, and the fourth outer conductor 63 connects the other end of the second connection pad 132 and the second shielding line 441. Among them, the first outer conductor 60, the second outer conductor 61, the third outer conductor 62, and the fourth outer conductor 63 are all formed by electroplating.

[0104] S11: Please refer to Figure 10 , a first protective layer 70 is provided on the first outer conductor 60, the second outer conductor 61, and the first shielding line 431, and a second protective layer 71 is provided on the third outer conductor 62, the fourth outer conductor 63, and the second shielding line 441.

[0105] In this embodiment, the materials of the first protective layer 70 and the second protective layer 71 are polyimide.

[0106] S12: Please refer to Figure 11 , a part of the first outer conductor 60, a part of the first inner conductor 20, a part of the first connection pad 131, and a part of the third outer conductor 62 within the first enclosed area 102 are cut along the thickness direction A, so that another part of the first outer conductor 60, another part of the first inner conductor 20, another part of the first connection pad 131, and another part of the third outer conductor 62 together form a first lateral shielding body 80. Two ends of the first lateral shielding body 80 are respectively connected to one end of the first shielding line 431 and one end of the second shielding line 441. Similarly, a part of the second outer conductor 61, a part of the second inner conductor 21, a part of the second connection pad 132, and a part of the fourth outer conductor 63 within the second enclosed area 103 are cut along the thickness direction A, so that another second outer conductor 61, another part of the second inner conductor 21, another part of the second connection pad 132, and another part of the fourth outer conductor 63 together form a second lateral shielding body 81. Two ends of the second lateral shielding body 81 are respectively connected to the other end of the first shielding line 431 and the other end of the second shielding line 441, and the transmission line 100 is obtained.

[0107] In this embodiment, the manufacturing method of the transmission line 100 further includes the steps of:

[0108] S13: Refer to Figure 12 , a third protective layer 90 is provided on the first lateral shielding body 80, and both ends of the third protective layer 90 are respectively connected to the first protective layer 70 and the second protective layer 71. Similarly, a fourth protective layer 91 is provided on the second lateral shielding body 81, and both ends of the fourth protective layer 91 are respectively connected to the first protective layer 70 and the second protective layer 71. Wherein, the third protective layer 90 and the fourth protective layer 91 can be formed by three-dimensional printing, and the materials of the third protective layer 90 and the fourth protective layer 91 are the same as the material of the first protective layer 70.

[0109] Compared with the prior art, the manufacturing method of the transmission line 100 provided by this application has the following advantages:

[0110] (1) By removing some of the enclosing areas (the first enclosing area 102, the second enclosing area 103), the remaining enclosing areas form lateral shielding bodies (the first lateral shielding body 80, the second lateral shielding body 81). The lateral shielding bodies are connected to the shielding lines (the first shielding line 431, the second shielding line 441) to form a shielding cavity, which can achieve omnidirectional electromagnetic shielding of the signal lines (the first signal line, the second signal line). At the same time, the shielding cavity has good structural stability, so that stable expected shielding effects can be maintained during the dynamic bending and static bending processes of the transmission line 100, thereby ensuring the overall performance and signal quality of the wireless communication system in the high-frequency band (range greater than 50 GHz).

[0111] (2) The method of forming the lateral shielding body by cutting some of the enclosing areas is beneficial to avoiding the micro-connection design in the traditional plating hole process, which is not only convenient for processing, but also can achieve full coverage of the signal lines.

[0112] In addition, refer to Figure 12 , this embodiment of the application also provides a transmission line 100, including signal lines (the first signal line, the second signal line), a first lateral shielding body 80, a second lateral shielding body 81, a first shielding line 431, and a second shielding line 441. The first lateral shielding body 80, the first shielding line 431, the second lateral shielding body 81, and the second shielding line 441 are sequentially connected end to end to form a shielding cavity (not marked), and the signal lines are arranged in the shielding cavity. The transmission line 100 can be a radio frequency transmission line or an antenna, and is used for signal transmission in a frequency range above 50 GHz and maintains a stable shielding effect.

[0113] The above description is only a specific implementation of an optimization of the present application, but in the actual application process, it cannot be limited to this implementation. For those of ordinary skill in the art, other deformations and changes made according to the technical concept of the present application should fall within the protection scope of the present application.

Claims

1. A manufacturing method of a fully shielded stacked RF transmission line, characterized in that, it includes the steps of: providing a core board, the core board is divided into a shielded area, a first enclosed area and a second enclosed area, the shielded area is arranged between the first enclosed area and the second enclosed area, a signal line is arranged in the shielded area, a first inner conductor is arranged in the first enclosed area, and a second inner conductor is arranged in the second enclosed area; arranging a first side board on one side of the core board, the first side board includes a first outer conductor, a second outer conductor and a first shielding line, the first shielding line is connected between the first outer conductor and the second outer conductor, the first outer conductor corresponds to the first enclosed area, the second outer conductor corresponds to the second enclosed area, the first shielding line corresponds to the shielded area, the first outer conductor is connected to one end of the first inner conductor, and the second outer conductor is connected to one end of the second inner conductor; arranging a second side board on the other side of the core board, the second side board includes a third outer conductor, a fourth outer conductor and a second shielding line, the second shielding line is connected between the third outer conductor and the fourth outer conductor, the third outer conductor corresponds to the first enclosed area, the fourth outer conductor corresponds to the second enclosed area, the second shielding line corresponds to the shielded area, the third outer conductor is connected to the other end of the first inner conductor, and the fourth outer conductor is connected to the other end of the second inner conductor; removing a part of the first inner conductor, a part of the first outer conductor and a part of the third outer conductor corresponding to the first enclosed area, and connecting the other part of the first outer conductor, the other part of the first inner conductor and the other part of the third outer conductor in sequence to form a first side shielding body, and both ends of the first side shielding body are respectively connected to one end of the first shielding line and one end of the second shielding line; removing a part of the second inner conductor, a part of the second outer conductor and a part of the fourth outer conductor corresponding to the second enclosed area, and connecting the other part of the second outer conductor, the other part of the second inner conductor and the other part of the fourth outer conductor in sequence to form a second side shielding body, and both ends of the second side shielding body are respectively connected to the other end of the first shielding line and the other end of the second shielding line to obtain the fully shielded stacked RF transmission line.

2. The manufacturing method according to claim 1, characterized in that, the core board further includes an inner insulating layer, the signal line includes a first signal line and a second signal line, the first signal line and the second signal line are respectively arranged on opposite sides of the inner insulating layer, and the manufacturing method of the core board includes the steps of: A first slot and a second slot are provided on the inner substrate, the inner substrate comprising the inner insulating layer and a first inner copper foil layer and a second inner copper foil layer disposed on opposite sides of the inner insulating layer, the first slot and the second slot both penetrating through the first inner copper foil layer and the inner insulating layer; a first inner conductor is disposed in the first slot, and a second inner conductor is disposed in the second slot, and the first inner copper foil layer is etched to form the first signal line layer, and the second inner copper foil layer is etched to form the second signal line layer.

3. The manufacturing method according to claim 1, wherein, the first side plate further comprises a first outer insulating layer, and the manufacturing method of the first side plate comprises the steps of: a first through hole and a second through hole are provided on the first outer substrate, the first outer substrate comprising the first outer insulating layer and a first outer copper foil layer, the first outer insulating layer being disposed between the core board and the first outer copper foil layer, the first through hole and the second through hole both penetrating through the first outer copper foil layer and the first outer insulating layer; a first outer conductor is disposed in the first through hole, and a second outer conductor is disposed in the second through hole, and the first outer copper foil layer is etched to form the first shielding line.

4. The manufacturing method according to claim 1, wherein, the second side plate further comprises a second outer insulating layer, and the manufacturing method of the second side plate comprises the steps of: a third through hole and a fourth through hole are provided on the second outer substrate, the second outer substrate comprising the second outer insulating layer and a second outer copper foil layer, the second outer insulating layer being disposed between the core board and the second outer copper foil layer, the third through hole and the fourth through hole both penetrating through the second outer copper foil layer and the second outer insulating layer; a third outer conductor is disposed in the third through hole, and a fourth outer conductor is disposed in the fourth through hole, and the second outer copper foil layer is etched to form the second shielding line.

5. The manufacturing method according to claim 1, wherein, it further comprises the steps of: a first adhesive layer is disposed between one side of the core board and the first side plate, and the first outer conductor and the second outer conductor penetrate through the first adhesive layer, a second adhesive layer is disposed between the other side of the core board and the second side plate, and the third outer conductor and the fourth outer conductor penetrate through the second adhesive layer.

6. The manufacturing method according to claim 1, wherein, both the first outer conductor and the third outer conductor are formed at both ends of the first inner conductor by electroplating, and both the second outer conductor and the fourth outer conductor are formed at both ends of the second inner conductor by electroplating.

7. The manufacturing method according to claim 1, wherein, Removing a part of the first inner conductor, a part of the first outer conductor, and a part of the third outer conductor corresponding to the first enclosed area by laser etching, and removing a part of the second inner conductor, a part of the second outer conductor, and a part of the fourth outer conductor corresponding to the second enclosed area by laser etching.

8. The manufacturing method according to claim 1, characterized in that it further comprises the steps of: providing a first protective layer on the first shielding line, the first protective layer covering one end of the first lateral shielding body and one end of the second lateral shielding body, providing a second protective layer on the second shielding line, the second protective layer covering the other end of the first lateral shielding body and the other end of the second lateral shielding body.

9. The manufacturing method according to claim 1, characterized in that it further comprises the steps of: providing a third protective layer on the first lateral shielding body, and providing a fourth protective layer on the second lateral shielding body.

10. A fully shielded stacked radio frequency transmission line, characterized in that it comprises a signal line, a first lateral shielding body, a second lateral shielding body, a first shielding line, and a second shielding line. The first lateral shielding body, the first shielding line, the second lateral shielding body, and the second shielding line are sequentially connected end to end to form a shielding cavity, and the signal line is disposed in the shielding cavity.

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