A micro-coaxial radio frequency probe based on copper-nickel composite additive manufacturing process

Abstract

The present invention discloses a micro-coaxial radio frequency probe based on a copper-nickel composite additive manufacturing process, which belongs to the field of microwave radio frequency technology. The probe comprises a GSG needle tip, a rectangular micro-coaxial line and a micro-coaxial line-rectangular waveguide conversion structure. The rectangular micro-coaxial line comprises an outer conductor, an inner conductor and a 1 / 4 wavelength short-circuit branch support structure. The inner conductor is arranged in the outer conductor. The rectangular micro-coaxial line is arranged in the outer conductor along the center line of the outer conductor. The rear end of the rectangular micro-coaxial line is connected to the micro-coaxial line-rectangular waveguide conversion structure. A rectangular waveguide interface is provided at the micro-coaxial line-rectangular waveguide conversion structure. A 1 / 4 wavelength short-circuit branch support structure is extended from the inner conductor in the rectangular micro-coaxial line. The GSG needle tip is used to convert the TEM mode into a coplanar waveguide TEM mode. The micro-coaxial line-rectangular waveguide conversion structure is used to realize the conversion between the TEM mode and the TE10 mode. The inner conductor thickness of the GSG needle tip is greater than the outer conductor thickness by 10 μm. The present invention provides three different designs, and the operating frequency bands are W band (75-110 GHz), D band (110-170 GHz) and G band (140-220 GHz).

Description

Technical Field

[0001] The present invention belongs to the field of microwave radio frequency technology, and in particular relates to a design method for a micro-coaxial radio frequency probe based on a copper-nickel composite additive manufacturing process. Background Art

[0002] In recent years, millimeter-wave devices have been widely used in communications and radar systems. Due to their small size and high operating frequency, placing coaxial or waveguide connectors on these devices is difficult due to performance, cost, and space constraints. Therefore, on-chip probes have become an indispensable tool for wafer-level testing. Currently, commercial ACP probes are commonly used. However, these probes are expensive and lack flexibility, making on-chip testing across different frequency bands inconvenient.

[0003] A microcoaxial cable consists of a suspended inner conductor surrounded by a grounded outer conductor. Microcoaxial cables are fabricated using microfabrication techniques and additive manufacturing, stacking raw materials layer by layer. Compared to traditional planar microstrip devices, millimeter-wave devices developed using microcoaxial technology exhibit wide bandwidth, high isolation, low loss, and high power capacity, while retaining the advantages of planar devices, such as high integration density. RF devices fabricated using copper-based air microcoaxial technology exhibit excellent performance in terms of miniaturization, transmission loss, and synthesis efficiency. This technology possesses unique advantages and enormous application potential in the miniaturization and high-density integration of millimeter-wave systems.

[0004] Metal micromachining technology integrates multiple processes, including photolithography, electroplating, and chemical mechanical polishing. During the electroplating process, the plating speed is not always uniform. The electric field is always concentrated in conductive patterns surrounded by large insulating areas and near the edges of the pattern. The non-uniformity of the electric field produces a higher local current density on the cathode surface in these areas, which is commonly known as current clustering. This phenomenon can lead to large differences in the electrostatic field distribution on the layout surface during electroplating, resulting in uneven copper plating thickness, which increases the difficulty of subsequent polishing and affects the overall processing accuracy.

[0005] The inventor team previously applied for a micro-coaxial RF probe based on a multi-material additive manufacturing process. The probe has good RF performance, but its mechanical properties need to be improved. In addition, the probe is large in size and the cost of a single probe is high. Summary of the Invention

[0006] In order to solve the above problems and achieve the above objectives, the present invention provides a micro-coaxial radio frequency probe based on a copper-nickel composite additive manufacturing process. On the basis of the copper-based air micro-coaxial technology, a nickel layer is added to improve the mechanical properties of the probe, aiming to design a low-cost, highly flexible radio frequency probe.

[0007] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is a micro-coaxial RF probe based on a copper-nickel composite additive manufacturing process, comprising a GSG needle tip, a rectangular micro-coaxial line and a micro-coaxial line-rectangular waveguide conversion structure, the rectangular micro-coaxial line comprising an outer conductor, an inner conductor and a 1 / 4 wavelength short-circuit branch support structure, the inner conductor is arranged in the outer conductor, the rectangular micro-coaxial line is arranged in the outer conductor along the center line of the outer conductor, the rear end of the rectangular micro-coaxial line is connected to the micro-coaxial line-rectangular waveguide conversion structure, a rectangular waveguide interface is arranged at the micro-coaxial line-rectangular waveguide conversion structure, a 1 / 4 wavelength short-circuit branch support structure extends from the inner conductor in the rectangular micro-coaxial line, the GSG needle tip is used to convert the TEM mode into a coplanar waveguide TEM mode, and the micro-coaxial line-rectangular waveguide conversion structure is used to realize the conversion between the TEM mode and the TE10 mode; the inner conductor thickness of the GSG needle tip is 10 μm greater than the outer conductor thickness; the rectangular micro-coaxial line is a copper-nickel composite layer structure, and the nickel layer is located in the layer where the inner conductor is located.

[0008] The front end of the quarter-wavelength short-circuit branch support structure is connected to the inner conductor of the micro-coaxial transmission line, and the rear end of the branch support structure is connected to the outer conductor of the micro-coaxial transmission line, used to support the inner conductor of the micro-coaxial transmission line. Chamfering is performed at the short-circuit branch connection to reduce stress and improve the mechanical properties of the probe.

[0009] The thickness of the nickel layer is 25 μm.

[0010] The copper-nickel composite layer structure includes a five-layer structure, the inner conductor is located in the third layer, the outer conductor is located in the first to fifth layers, the first two layers of the third layer are nickel layers, and the third layer is a copper layer. The thickness of the first layer is L1 = 50μm, the thickness of the second layer is L2 = 100μm, and the third layer is divided into three layers, among which L 3-1 =10μm, L 3-2 =15μm, L 3-3 =50μm, the fourth layer thickness L4 =100μm, and the fifth layer thickness L5 =50μm.

[0011] The operating frequency bands are W-band 75-110GHz, D-band 110-170GHz and G-band 140-220GHz.

[0012] A plating sheet or plating hole is provided at the location of the outer conductor insulation area.

[0013] A positioning hole is provided on the outer conductor of the probe.

[0014] The length l2 of the short-circuit branch of the 1 / 4 wavelength short-circuit branch support structure is 0.6 mm to 0.93 mm, the width w2 is 0.10 mm, and the probe tip spacing w3 is 0.10 mm or 0.075 mm.

[0015] The 1 / 4 wavelength short-circuit branch support structure includes a first short-circuit branch support structure, a second short-circuit branch support structure and a third short-circuit branch support structure. The first short-circuit branch support structure, the second short-circuit branch support structure and the third short-circuit branch support structure are arranged in sequence along the axial direction of the inner conductor. The first short-circuit branch support structure is symmetrically arranged on both sides of the inner conductor, and the second short-circuit branch support structure and the third short-circuit branch support structure are respectively arranged on both sides of the inner conductor.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects:

[0017] The present invention proposes a micro-coaxial RF probe based on a copper-nickel composite additive manufacturing process. Based on the copper-based air micro-coaxial technology, a nickel layer is added to improve the mechanical properties of the probe. Due to the high hardness of nickel, it is not suitable for a dielectric support structure. The present invention uses a 1 / 4 short-circuit branch instead of a dielectric support structure. While ensuring RF performance, it achieves the same support effect for the inner conductor, improves mechanical properties, eliminates screw holes, reduces the probe volume, and further reduces the cost of a single probe.

[0018] The present invention is an improvement on the micro-coaxial RF probe based on a multi-material additive manufacturing process. The probe has good RF performance, but its mechanical performance needs to be improved. The processing material of the present invention adopts a copper-nickel composite material, so that when the probe tip is deformed, sufficient contact force is obtained between the device to be tested and the probe, and it has good mechanical properties.

[0019] Furthermore, accompanying plating sheets or accompanying plating holes are set at the locations of large insulating areas to bear part of the current, thereby reducing the high current density in the actual layout, increasing the uniformity of the plating, reducing the difficulty of subsequent polishing, and improving the accuracy of the overall design. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To more clearly illustrate the embodiments of the present invention or the prior art solutions, the following briefly introduces the drawings used in the embodiments or the prior art solutions. It should be noted that the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0021] Figure 1a An oblique isometric view of a micro-coaxial radio frequency probe A based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention; Figure 1b for Figure 1a Schematic diagram of the local structure;

[0022] Figure 2 A half-sectional view of a micro-coaxial radio frequency probe A based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0023] Figure 3 A cross-sectional view of a micro-coaxial radio frequency probe A based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0024] Figure 4 The return loss and insertion loss simulation results of a micro-coaxial RF probe A based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention;

[0025] Figure 5a An oblique isometric view of a micro-coaxial radio frequency probe B based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention; Figure 5b for Figure 5a Schematic diagram of the local structure;

[0026] Figure 6 A half-sectional view of a micro-coaxial radio frequency probe B based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0027] Figure 7 A cross-sectional view of a micro-coaxial radio frequency probe B based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0028] Figure 8 The return loss and insertion loss simulation results of a micro-coaxial RF probe B based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention;

[0029] Figure 9a An oblique isometric view of a micro-coaxial radio frequency probe C based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention; Figure 9b for Figure 9a Schematic diagram of the local structure;

[0030] Figure 10 A half-sectional view of a micro-coaxial radio frequency probe C based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0031] Figure 11 A cross-sectional view of a micro-coaxial radio frequency probe C based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0032] Figure 12 The return loss and insertion loss simulation results of a micro-coaxial RF probe C based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention;

[0033] Figure 13 An oblique isometric view of a micro-coaxial radio frequency probe fixture based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0034] Figure 14A half-sectional view of a micro-coaxial radio frequency probe fixture based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0035] Figure 15 A left view of a micro-coaxial radio frequency probe fixture based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0036] Figure 16 A right view of a micro-coaxial radio frequency probe fixture based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention;

[0037] Figure 17 A cross-sectional view of a micro-coaxial transmission line in a micro-coaxial radio frequency probe manufacturing process based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention; DETAILED DESCRIPTION

[0038] In order to make the objects, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be noted that the described embodiments are only part of the embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0039] In the description of the embodiments of the present invention, it needs to be understood that the terms "top surface", "bottom surface", "left side", "right side", "horizontal direction" and "vertical direction" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and it cannot be assumed that the indicated elements or devices are in a specific orientation.

[0040] In the description of the embodiments of the present invention, the structural dimensions given are preferred parameters. With reference to the embodiments of the present invention, the dimensional parameters of each component may be modified to further obtain the actual required performance.

[0041] The present invention provides a micro-coaxial radio frequency probe based on a copper-nickel composite additive manufacturing process, comprising a GSG needle tip 1, a rectangular micro-coaxial line 2, and a micro-coaxial line-to-rectangular waveguide conversion structure 3. The rectangular micro-coaxial line 2 includes an outer conductor, an inner conductor, and a 1 / 4 wavelength short-circuit branch support structure. The inner conductor is arranged in the outer conductor. The rectangular micro-coaxial line 2 is arranged in the outer conductor along the centerline of the outer conductor. The rear end of the rectangular micro-coaxial line 2 is connected to the micro-coaxial line-to-rectangular waveguide conversion structure 3. A rectangular waveguide interface is provided at the micro-coaxial line-to-rectangular waveguide conversion structure 3. A 1 / 4 wavelength short-circuit branch support structure extends from the inner conductor of the rectangular micro-coaxial line 2. The GSG needle tip 1 is used to convert the TEM mode into a coplanar waveguide TEM mode. The micro-coaxial line-to-rectangular waveguide conversion structure 3 is used to achieve conversion between the TEM mode and the TE10 mode. The present invention provides three different designs, with operating frequency bands of W band (75-110 GHz), D band (110-170 GHz), and G band (140-220 GHz). The outer conductor of the micro-coaxial radio frequency probe of the present invention is provided with a positioning hole 4 .

[0042] The front end of the quarter-wavelength short-circuit branch support structure is connected to the inner conductor of the micro-coaxial transmission line, and the rear end of the branch support structure is connected to the outer conductor of the micro-coaxial transmission line, used to support the inner conductor of the micro-coaxial transmission line. Chamfering is performed at the short-circuit branch connection to reduce stress and improve the mechanical properties of the probe.

[0043] The 1 / 4 wavelength short-circuit branch support structure includes a first short-circuit branch support structure, a second short-circuit branch support structure and a third short-circuit branch support structure. The first short-circuit branch support structure, the second short-circuit branch support structure and the third short-circuit branch support structure are arranged in sequence along the axial direction of the inner conductor. The first short-circuit branch support structure is symmetrically arranged on both sides of the inner conductor, and the second short-circuit branch support structure and the third short-circuit branch support structure are respectively arranged on both sides of the inner conductor.

[0044] As a preferred embodiment, the thickness of the inner conductor of the GSG needle tip is 10 μm greater than the thickness of the outer conductor; and the thickness of the nickel layer is 25 μm.

[0045] An air dielectric layer is provided between the outer conductor and the inner conductor of the micro-coaxial line.

[0046] See also Figure 1a 、 Figure 1b 、 Figure 2 and Figure 3 , Figure 1a An oblique isometric view of a micro-coaxial radio frequency probe A based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention, Figure 1b A detailed view of the tip of a micro-coaxial radio frequency probe A based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention. Figure 2A half-section view of a micro-coaxial radio frequency probe A based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention, Figure 3 A cross-sectional view of a micro-coaxial radio frequency probe A based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention.

[0047] The radio frequency probe A comprises: a GSG needle tip 1, a rectangular micro-coaxial line 2, a micro-coaxial line-WR-10 rectangular waveguide conversion structure 3, and a positioning hole 4 for positioning the probe and the fixture.

[0048] The micro-coaxial RF probe A, manufactured using a copper-nickel composite additive manufacturing process, has an inner conductor length l1 of 3.88 mm, a width w1 of 0.10 mm, and a thickness t1 of 0.05 mm. The short-circuit stub length l2 is 0.93 mm, w2 is 0.10 mm, and the probe tip spacing w3 is 0.10 mm. The probe has an overall length a1 of 5.75 mm and a width b1 of 7.60 mm. The waveguide interface length a2 is 0.310 mm and b2 is 0.438 mm. The positioning hole radius r1 is 0.825 mm, the accompanying plating hole length r2 is 0.25 mm, and the dimensions are 0.25 mm x 0.25 mm.

[0049] Figure 4 The return loss and insertion loss simulation and test results of a micro-coaxial RF probe A based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention are shown. The operating frequency band is the W band (75-110 GHz). It can be seen that the return loss in the operating frequency band is all maintained below -20 dB, indicating that the probe performance is good.

[0050] See also Figure 5a 、 Figure 5b 、 Figure 6 and Figure 7 , Figure 5a An oblique isometric view of a micro-coaxial radio frequency probe B based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention, Figure 5b A detailed view of the tip of a micro-coaxial radio frequency probe B based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention. Figure 6 A half-section view of a micro-coaxial radio frequency probe B based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention, Figure 7 A cross-sectional view of a micro-coaxial radio frequency probe B based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention.

[0051] The radio frequency probe B comprises: a GSG needle tip 1, a rectangular micro-coaxial line 2, a micro-coaxial line-WR-6 rectangular waveguide conversion structure 3, and a positioning hole 4 for positioning the probe and the fixture.

[0052] The micro-coaxial RF probe B, manufactured using a copper-nickel composite additive manufacturing process, has an inner conductor length l1 of 5.06 mm, a width w1 of 0.10 mm, and a thickness t1 of 0.05 mm. The short-circuit stub length l2 is 0.73 mm, w2 is 0.10 mm, and the probe tip spacing w3 is 0.10 mm. The probe has an overall length a1 of 6.42 mm and a width b1 of 7.60 mm. The waveguide interface length a2 is 0.245 mm and b2 is 0.333 mm. The positioning hole radius r1 is 0.825 mm, the accompanying plating hole length r2 is 0.25 mm, and the dimensions are 0.25 mm x 0.25 mm.

[0053] Figure 8 The return loss and insertion loss simulation and test results of a micro-coaxial RF probe B based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention are shown. The operating frequency band is the D band (110-170 GHz). It can be seen that the return loss in the operating frequency band is all maintained below -20 dB, indicating that the probe performance is good.

[0054] See also Figure 1a 、 Figure 1b 、 Figure 2 and Figure 3 , Figure 9a An oblique isometric view of a micro-coaxial radio frequency probe C based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention, Figure 9b A detailed diagram of the tip of a micro-coaxial radio frequency probe C based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention. Figure 10 A half-section view of a micro-coaxial radio frequency probe C based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention, Figure 11 A cross-sectional view of a micro-coaxial radio frequency probe C based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention.

[0055] The radio frequency probe C comprises: a GSG needle tip 1, a rectangular micro-coaxial line 2, a micro-coaxial line-WR-5 rectangular waveguide conversion structure 3, and a positioning hole 4 for positioning the probe and the fixture.

[0056] The micro-coaxial RF probe C, manufactured using a copper-nickel composite additive manufacturing process, has an inner conductor length l1 of 4.12 mm, a width w1 of 0.10 mm, and a thickness t1 of 0.05 mm. The short-circuit stub length l2 is 0.60 mm, w2 is 0.10 mm, the probe tip spacing w3 is 0.075 mm, the probe's total length a1 is 6.00 mm, its width b1 is 7.60 mm, the waveguide interface length a2 is 0.373 mm, and b2 is 0.244 mm. The positioning hole radius r1 is 0.825 mm, the accompanying plating hole length r2 is 0.25 mm, and the dimensions are 0.25 mm x 0.25 mm.

[0057] Figure 12 The return loss and insertion loss simulation and test results of a micro-coaxial RF probe C based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention are as follows: the operating frequency band is the G band (140-220GHz), and it can be seen that the return loss within the operating frequency band is all maintained below -15dB, indicating that the probe performance is good.

[0058] Figure 13 An oblique isometric view of a micro-coaxial radio frequency probe fixture based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention. Figure 14 A half-sectional view of a micro-coaxial radio frequency probe fixture based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention, Figure 15 This is a left view of a micro-coaxial radio frequency probe fixture based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention. Figure 16 The right side view of a micro-coaxial RF probe fixture based on a copper-nickel composite additive manufacturing process provided in an embodiment of the present invention. The RF probe fixture includes: a curved waveguide 11, a waveguide flange 12, a base 13 and a support structure 14. Among them, the flange is a part that connects the waveguide ports to each other, and the waveguide flange is a flange fixed to the waveguide terminal according to the design, and can be installed with accessories for alignment and clamping with the matching flange. The dimensions of all waveguide flanges in the embodiment of the present invention are the standard rectangular waveguide flange dimensions under the probe working frequency band. The dimensions of the waveguide interface of RF probe A are 2.54mm×1.27mm, the dimensions of the waveguide interface of RF probe B are 1.651mm×0.826mm, and the dimensions of the waveguide interface of RF probe C are 1.295mm×0.648mm. The thickness of the waveguide flange is 4mm.

[0059] The angle between the support structure and the bottom of the base is 30°, ensuring that the probe maintains a 30° angle (rot1) with the DUT during testing. One end of the curved waveguide is connected to the waveguide flange, and the other end is connected to the support structure. Screw holes are designed in the support structure, and the support structure and base are connected via threads. The back cavity depth h in the base of RF probe A is 0.61mm, the back cavity depth h in the base of RF probe B is 0.32mm, and the back cavity depth h in the base of RF probe C is 0.21mm. The rear screw hole is the same size as the screw hole in the standard probe station needle seat.

[0060] Figure 17A cross-sectional view of a micro-coaxial transmission line of a micro-coaxial radio frequency probe processing process based on a copper-nickel composite additive manufacturing process provided by an embodiment of the present invention, wherein the white part is copper, the black part is nickel, and the rectangular micro-coaxial line (2) is a copper-nickel composite layer structure. The copper-nickel composite layer structure includes a five-layer structure, the inner conductor is located in the third layer structure, the outer conductor is located in the first to fifth layers, the first two layers of the third layer are nickel layers, and the third layer is a copper layer. The thickness of the first layer is L1 = 50 μm, the thickness of the second layer is L2 = 100 μm, and the third layer is divided into three layers, wherein L 3-1 =10μm, L 3-2 =15μm, L 3-3 =50μm, the fourth layer thickness L4 = 100μm, the fifth layer thickness L5 = 50μm. 3-1 It is used to process the height difference of 10μm between the inner and outer conductors at the needle tip, and the total thickness of nickel is 25μm, which ensures the mechanical properties of the probe.

[0061] The above is a description of a micro-coaxial radio frequency probe and its manufacturing method provided by the present invention. For those skilled in the art, according to the concept of the embodiments of the present invention, there may be changes in the specific implementation and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A micro-coaxial radio frequency probe based on a copper-nickel composite additive manufacturing process, characterized in that: The invention comprises a GSG needle tip (1), a rectangular micro-coaxial line (2) and a micro-coaxial line-rectangular waveguide conversion structure (3), wherein the rectangular micro-coaxial line (2) comprises an outer conductor, an inner conductor and a 1 / 4 wavelength short-circuit branch support structure, the inner conductor is arranged in the outer conductor, and the inner conductor is arranged in the outer conductor along the center line of the outer conductor, the rear end of the rectangular micro-coaxial line (2) is connected to the micro-coaxial line-rectangular waveguide conversion structure (3), a rectangular waveguide interface is arranged at the micro-coaxial line-rectangular waveguide conversion structure (3), the inner conductor in the rectangular micro-coaxial line (2) extends out of the 1 / 4 wavelength short-circuit branch support structure, the GSG needle tip (1) is used to convert the TEM mode into the coplanar waveguide TEM mode, and the micro-coaxial line-rectangular waveguide conversion structure (3) is used to realize the conversion between the TEM mode and the TE10 mode; the thickness of the inner conductor of the GSG needle tip (1) is greater than the thickness of the outer conductor by 10 μm; the rectangular micro-coaxial line (2) is a copper-nickel composite layer structure, and the nickel layer is located at the layer where the inner conductor is located; The 1 / 4 wavelength short-circuit branch support structure includes a first short-circuit branch support structure, a second short-circuit branch support structure and a third short-circuit branch support structure. The first short-circuit branch support structure, the second short-circuit branch support structure and the third short-circuit branch support structure are arranged in sequence along the axial direction of the inner conductor. The first short-circuit branch support structure is symmetrically arranged on both sides of the inner conductor, and the second short-circuit branch support structure and the third short-circuit branch support structure are respectively arranged on both sides of the inner conductor.

2. The micro-coaxial radio frequency probe based on the copper-nickel composite additive manufacturing process according to claim 1 is characterized in that: The branch front end of the 1 / 4 wavelength short-circuit branch support structure is connected to the inner conductor of the rectangular micro-coaxial line (2), and the branch rear end of the 1 / 4 wavelength short-circuit branch support structure is connected to the outer conductor of the rectangular micro-coaxial line (2), and is used to support the inner conductor of the rectangular micro-coaxial line (2); a chamfered structure is provided at the short-circuit branch connection.

3. The micro-coaxial radio frequency probe based on the copper-nickel composite additive manufacturing process according to claim 1 is characterized in that: The thickness of the nickel layer is 25 μm.

4. The micro-coaxial radio frequency probe based on the copper-nickel composite additive manufacturing process according to claim 1 is characterized in that: Copper-nickel composite layer structure, including five layers, the inner conductor is located in the third layer, the outer conductor is located in the first to fifth layers, the first layer thickness L 1=50μm, thickness of the second layer L 2=100μm, the third layer is divided into three layers, the first two layers are nickel layers, the third layer is copper layer, L 3-1 =10μm, L 3-2 =15μm, L 3-3 =50μm, thickness of the fourth layer L 4=100μm, thickness of the fifth layer L 5=50μm.

5. The micro-coaxial radio frequency probe based on the copper-nickel composite additive manufacturing process according to claim 1 is characterized in that: The operating frequency bands are W-band 75-110GHz, D-band 110-170GHz and G-band 140-220GHz.

6. The micro-coaxial radio frequency probe based on the copper-nickel composite additive manufacturing process according to claim 1 is characterized in that: A plating sheet or plating hole is provided at the location of the outer conductor insulation area.

7. The micro-coaxial radio frequency probe based on the copper-nickel composite additive manufacturing process according to claim 1 is characterized in that: A positioning hole (5) is provided on the outer conductor of the probe.

8. The micro-coaxial radio frequency probe based on the copper-nickel composite additive manufacturing process according to claim 1 is characterized in that: The short-circuit branch length l2 of the 1 / 4 wavelength short-circuit branch support structure is 0.6 mm to 0.93 mm, its width w2 is 0.10 mm, and the probe tip spacing w3 is 0.10 mm or 0.075 mm.

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