Low-discontinuity air coplanar radio frequency microwave probe and preparation method thereof

Abstract

The invention relates to the technical field of microwave circuit testing equipment, in particular to a low-discontinuity air coplanar radio frequency microwave probe and a preparation method, and aims to reduce the influence of a dielectric support column on probe discontinuity and improve the sensitivity of the probe. The effective dielectric constant of the supporting medium is reduced in a punching mode, so that the supporting medium is closer to air, and discontinuity is reduced. According to the embodiment of the invention, for the discontinuous capacitance introduced by internal multistage broadband matching, the high-resistance transmission line is introduced through simulation optimization to compensate the discontinuous capacitance. According to the embodiment of the invention, simulation optimization is carried out on the tail part of the tip of the probe body for an internal unique interconnection welding spot, so that impedance step caused by the welding spot is reduced, and discontinuity is reduced. According to the embodiment of the invention, the needle point of the probe body is positioned and clamped by glass ribbon line eutectic welding, so that the distance between the transmission needle and the ground needle is effectively ensured, and the strength of the test needle point is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of microwave circuit testing equipment, and in particular to a low-discontinuity air coplanar radio frequency microwave probe and a preparation method thereof. Background Art

[0002] The development of the integrated circuit design industry has brought about a large demand for design verification testing. Testing is not only a part of the integrated circuit industry chain, but also a key step in the verification of integrated circuit products before they leave the factory. The probe accurately measures the characteristics of integrated circuit wafer chips to improve the design and manufacturing process, which is crucial to the development of high-speed and microwave integrated circuits. Therefore, microwave integrated circuit testing technology occupies a very important position in the current integrated circuit industry.

[0003] International research on microwave probes began in the 1980s, with the United States being the main country to initiate the research. In the early 1980s, Tektronix of the United States produced the earliest RF wafer probe model, TMP9600. In 1983, Cascade Microtech launched the WPH probe, and the frequency of the WPH probe reached 50GHz in 1987 to meet the needs of the rapidly developing monolithic microwave integrated circuits (MMIC).

[0004] However, the probes at that time were made of coplanar ceramic material, which cannot be bent too much, so the elasticity of the pressure contact is not large and it is very easy to be damaged during testing. Even if it can be replaced, its high price still limits its application, and the RF frequency it supports is also low. In 1988, GGB Industries invented and patented a RF probe based on micro-coaxial cable. It uses micro-coaxial cable as the intermediate transition medium, significantly improves and extends the life of the probe through mechanical improvements, reduces the cost of rebuilding the probe, and simplifies the manufacturing process.

[0005] At the same time, Cascade demonstrated a new 40-GHz air-coplanar probe (ACP) in 1994. To date, many engineers use ACP to detect gold pressure points due to its soft material, non-destructive contact, clear tip and low loss. ACP probes have become the most widely used probes at this stage.

[0006] A traditional ACP RF microwave probe consists of the following parts:

[0007] The coaxial adapter connected to the test equipment, the transition from the test interface to the micro-coaxial cable, the conversion from the micro-coaxial cable to the planar waveguide (CPW), and the coplanar interface to the contact point part, that is, the needle tip.

[0008] It can be seen from the implementation structure of ACP that due to factors such as process welding solder joints, there must be discontinuous capacitance. The signal needs to complete multiple conversions when completing the test transmission, which affects the high-speed, dispersion-free transmission of the signal and causes signal distortion.

[0009] Based on this, it is necessary to develop and design a low-discontinuity air coplanar RF microwave probe. Summary of the invention

[0010] The embodiments of the present invention provide a low-discontinuity air coplanar radio frequency microwave probe and a preparation method thereof, which are used to solve the problem that microwave probes in the prior art need to complete multiple conversions during test transmission, thus affecting signal transmission.

[0011] In a first aspect, an embodiment of the present invention provides a low discontinuity air coplanar radio frequency microwave probe, comprising:

[0012] Housing, coaxial interface and probe assembly;

[0013] The coaxial interface comprises: an inner conductor and a fixing component;

[0014] The inner conductor is coaxially fixedly disposed inside the fixing assembly, and the front end of the inner conductor is exposed at the front end of the fixing assembly;

[0015] The probe assembly is fixedly arranged at the front end of the housing;

[0016] The coaxial interface is fixedly arranged at the rear end of the shell, and the front end of the inner conductor is connected to the rear end of the probe assembly as a whole.

[0017] In a possible implementation, the inner conductor is a cylinder with at least four steps;

[0018] The step diameter of the inner conductor increases from front to back;

[0019] The step at the front end of the inner conductor is connected to the rear end of the probe assembly;

[0020] The inner conductor is fixedly connected to the interior of the fixing assembly through steps other than the front end step and the rear end step.

[0021] In a possible implementation, the fixing assembly includes: a supporting medium and a coaxial shell, wherein the supporting medium is an insulator and the coaxial shell is a conductor;

[0022] The inner conductor is a cylinder, and the inner conductor passes through the supporting medium and is fixedly connected to the supporting medium;

[0023] The supporting medium is fixedly arranged inside the coaxial housing;

[0024] The front end of the coaxial shell is a cylinder, the front end of the coaxial shell is provided with a thread, and the coaxial shell is screwed to the shell through the thread at the front end.

[0025] In a possible implementation, the supporting medium includes: a first supporting medium and a second supporting medium;

[0026] The inner conductor is provided with a first mounting step and a second mounting step, the diameter of the first mounting step is larger than the diameter of the second mounting step, and the first mounting step is located at the rear end of the second mounting step;

[0027] The first supporting medium and the second supporting medium are both provided with mounting holes, the first mounting step of the inner conductor is fixed through the mounting hole of the first supporting medium, and the second mounting step of the inner conductor is fixed through the mounting hole of the second supporting medium;

[0028] The two end surfaces of the first supporting medium are provided with annular grooves, and the first supporting medium is provided with holes penetrating the two end surfaces.

[0029] In a possible implementation, the first supporting medium and the second supporting medium are both polyetheretherketone materials.

[0030] In a possible implementation, the probe assembly includes: a first strip line, a second strip line, and a probe body;

[0031] The first strip wire is welded above the needle tip of the probe body;

[0032] The second strip wire is welded below the needle tip of the probe body;

[0033] The first strip line and the second strip line are both glass substrates with gold-tin plated surfaces;

[0034] The surface areas of the first strip line and the second strip line are both smaller than the surface area of ​​the probe body, and the front end of the probe body and the rear end of the probe body are respectively exposed to the sandwich layer formed by the first strip line and the second strip line.

[0035] In a possible implementation, the housing includes: a first housing and a second housing;

[0036] The coaxial interface is fixedly arranged at the rear end of the housing, and the front end of the inner conductor is connected to the rear end of the probe assembly as a whole;

[0037] The probe assembly is arranged between the second shell and the first shell, and the probe assembly is pressed against the front end of the shell by pressing the second shell onto the first shell.

[0038] In a possible implementation manner, surfaces of the inner conductor, the first shell, and the second shell are respectively plated with Au.

[0039] In a second aspect, an embodiment of the present invention provides a method for preparing a low-discontinuity air coplanar radio frequency microwave probe, which is used to implement the low-discontinuity air coplanar radio frequency microwave probe as described in the first aspect or any possible implementation of the first aspect, and the method for preparing the low-discontinuity air coplanar radio frequency microwave probe comprises:

[0040] Processing the first tape line and the second tape line by thin film process;

[0041] The probe tip is precisely machined by UV-LIGA;

[0042] Electroplating Au on the inner conductor, the first shell and the second shell surface;

[0043] Fixing the inner conductor with a first supporting medium and a second supporting medium;

[0044] Fixing the inner conductor, the first supporting medium and the second supporting medium with a coaxial housing to form a coaxial interface;

[0045] Welding the first strip wire, the probe body, and the second strip wire into a sandwich structure;

[0046] Installing the coaxial interface in the first housing;

[0047] welding the sandwich structure to the first shell;

[0048] Welding the needle tip tail of the probe body to the coaxial joint;

[0049] welding the ground pin of the probe body to the first housing;

[0050] The second housing is welded to the first housing.

[0051] In a possible implementation, welding the first strip wire, the probe body, and the second strip wire into a sandwich structure includes:

[0052] Precisely positioning and welding the first strip wire on the probe body by CTOW eutectic welding;

[0053] The second strip line is welded under the probe body through ball planting.

[0054] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0055] The embodiment of the present invention discloses a low discontinuity air coplanar radio frequency microwave probe, which uses a punching method to reduce the effective dielectric constant of the supporting medium in order to reduce the influence of the dielectric support column on the probe discontinuity, so as to make it closer to air and reduce the discontinuity. The embodiment of the present invention compensates for the discontinuity capacitance introduced by the internal multi-stage broadband matching by introducing a high-resistance transmission line through simulation optimization. The embodiment of the present invention simulates and optimizes the tail of the probe body tip for the only internal interconnection solder joint to reduce the impedance step caused by the solder joint and reduce the discontinuity. The probe body tip of the embodiment of the present invention is made by ultraviolet lithography micro-electroforming process (UV-LIGA), which has extremely high precision and repeatability. The probe body tip of the embodiment of the present invention adopts glass strip wire eutectic welding for positioning and clamping, which effectively ensures the spacing between the transmission needle and the ground needle and ensures the strength of the test needle tip. In order to achieve a frequency range covering DC-67GHz, multi-stage step matching and multiple dielectric constant material matching are adopted. In order to obtain lower transmission loss, the inner conductor of the radio frequency microwave probe adopts an electroplating Au solution. In order to obtain sufficient contact force between the device under test and the probe, the probe body and the probe tip are made of nickel material with strong plasticity. At the same time, gold is electroplated on the nickel to reduce loss. In order to make the device under test more fully contact with the probe, the second shell is thinned and the bottom space is designed to be large enough to minimize the impact on the device under test. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0057] Figure 1 It is a front schematic diagram of a low discontinuity air coplanar radio frequency microwave probe provided by an embodiment of the present invention;

[0058] Figure 2 It is a schematic diagram of the main structure of a low discontinuity air coplanar radio frequency microwave probe provided by an embodiment of the present invention;

[0059] Figure 3 It is a schematic diagram of the coordination between the internal conductor and the supporting medium of the coaxial interface provided by an embodiment of the present invention;

[0060] Figure 4 is a schematic diagram of a coaxial interface supporting medium provided by an embodiment of the present invention;

[0061] Figure 5 It is a schematic diagram of the steel sleeve assembly of the coaxial interface provided by the embodiment of the present invention;

[0062] Figure 6 This is a schematic diagram of the coaxial interface assembly completion provided by an embodiment of the present invention;

[0063] Figure 7 It is a schematic diagram of the assembly and matching of the probe body needle tip, the first strip line and the second strip line provided by an embodiment of the present invention;

[0064] Figure 8 It is a schematic diagram of the interconnection between the probe sandwich structure and the coaxial interface provided by an embodiment of the present invention;

[0065] Fig. 9 It is a schematic diagram of the second housing provided by an embodiment of the present invention being assembled on the first housing to fix the probe body;

[0066] In the figure:

[0067] A first housing 110;

[0068] A second housing 120;

[0069] Inner conductor 210;

[0070] A first supporting medium 220;

[0071] A second supporting medium 230;

[0072] Coaxial housing 240;

[0073] Probe body 310;

[0074] First belt line 320;

[0075] Second belt line 330. DETAILED DESCRIPTION

[0076] In the following description, specific details such as specific system structures and technologies are provided for the purpose of illustration rather than limitation so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, and methods are omitted so as not to obscure the description of the present invention with unnecessary details.

[0077] In order to make the purpose, technical solutions and advantages of the present invention more clear, a specific implementation method will be described below in conjunction with the accompanying drawings.

[0078] The following is a detailed description of an embodiment of the present invention. This example is implemented based on the technical solution of the present invention, and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0079] Figure 1-9A schematic diagram of various parts of a low-discontinuity air coplanar radio frequency microwave probe provided in an embodiment of the present invention.

[0080] In a first aspect, an embodiment of the present invention provides a low discontinuity air coplanar radio frequency microwave probe, comprising:

[0081] Housing, coaxial interface and probe assembly;

[0082] The coaxial interface includes: an inner conductor 210 and a fixing component;

[0083] The inner conductor 210 is coaxially fixedly disposed inside the fixing component, and the front end of the inner conductor 210 is exposed at the front end of the fixing component;

[0084] The probe assembly is fixedly arranged at the front end of the housing;

[0085] The coaxial interface is fixedly disposed at the rear end of the housing, and the front end of the inner conductor 210 is connected to the rear end of the probe assembly as a whole.

[0086] In a possible implementation, the inner conductor 210 is a cylinder with at least four steps;

[0087] The step diameter of the inner conductor 210 increases from front to back;

[0088] The frontmost step of the inner conductor 210 is connected to the rear end of the probe assembly;

[0089] The inner conductor 210 is fixedly connected to the interior of the fixing assembly through steps other than the front end step and the rear end step.

[0090] In a possible implementation, the fixing assembly includes: a supporting medium and a coaxial housing 240, wherein the supporting medium is an insulator and the coaxial housing 240 is a conductor;

[0091] The inner conductor 210 is a cylinder, and the inner conductor 210 passes through the supporting medium and is fixedly connected to the supporting medium;

[0092] The supporting medium is fixedly disposed inside the coaxial housing 240;

[0093] The front end of the coaxial housing 240 is a cylinder, and a thread is provided on the front end of the coaxial housing 240 . The coaxial housing 240 is screwed to the housing through the thread on the front end.

[0094] In a possible implementation, the supporting medium includes: a first supporting medium 220 and a second supporting medium 230;

[0095] The inner conductor 210 is provided with a first mounting step and a second mounting step, the diameter of the first mounting step is larger than the diameter of the second mounting step, and the first mounting step is located at the rear end of the second mounting step;

[0096] The first supporting medium 220 and the second supporting medium 230 are both provided with mounting holes, the first mounting step of the inner conductor 210 is fixed through the mounting hole of the first supporting medium 220, and the second mounting step of the inner conductor 210 is fixed through the mounting hole of the second supporting medium 230;

[0097] The two end surfaces of the first supporting medium 220 are provided with annular grooves, and the first supporting medium 220 is provided with holes penetrating the two end surfaces.

[0098] In a possible implementation, the first supporting medium 220 and the second supporting medium 230 are both made of polyetheretherketone material.

[0099] Exemplarily, the handheld probe of the present invention is in the form of GSG, the coaxial inner conductor 210 and the middle needle of the probe are assembled together to form a signal transmission end, denoted as S, and the grounding needle is assembled on the housing 2 to form a grounding end, denoted as G. In order to meet the electrical performance indicators and facilitate testing and use, the handheld radio frequency microwave probe of the present invention can be designed with any different G and S spacings, and can be designed into a variety of microwave probe combinations such as GS, SG, GSG, GSGSG, GSGS, GSS, GSSG, SGS, SGSG and SSG.

[0100] To achieve low discontinuity, the designed probe does not use micro-coaxial cables and achieves a direct transition from coaxial connection to air coplanar.

[0101] In an application scenario of the present invention, the coaxial interface inner conductor 210 is processed into a cylinder with a length of φ1.27*17 mm according to the simulated size.

[0102] In one application scenario of the present invention, the front end of the coaxial interface inner conductor 210 is processed into a φ0.4*4mm step, a second step φ0.9*6mm, a third step φ0.8*1.5mm, a fourth step φ1.1*3mm, and a fifth step φ1.27*3mm.

[0103] In some application scenarios, the coaxial housing 240 of the coaxial interface is processed to adapt to the shape and size of a 2.4 mm-V-type connector, and the front end milled thread length is 4.9 mm.

[0104] In some application scenarios, the inner conductor 210 is fixed inside the coaxial housing 240 through two supporting media. The first supporting medium 220 of the coaxial interface is processed into φ0.4*1.5mm, with φ2.3*0.1mm deep annular grooves milled on both sides, φ0.8*1.5mm holes punched in the middle, and 6 φ0.5*1.5mm holes punched in the array.

[0105] The second supporting medium 230 of the coaxial interface is processed into φ1.7*2mm, and a φ0.4*4mm hole is punched in the middle.

[0106] In some scenarios, the inner conductor 210 and the first supporting medium 220 are fixed with a stainless steel threaded sleeve to form a probe coaxial interface.

[0107] In order to reduce the influence of the dielectric support column on the discontinuity of the probe, the embodiment of the present invention uses a punching method to reduce the effective dielectric constant of the supporting medium, making it closer to air and reducing the discontinuity.

[0108] In the embodiment of the present invention, the discontinuous capacitance introduced by the internal multi-stage broadband matching is compensated by introducing a high-resistance transmission line through simulation optimization.

[0109] The supporting medium of the embodiment of the present invention uses polyetheretherketone (PEEK) material. The dielectric constant of the polyetheretherketone material is 3.15, the dielectric constant is stable, and it can meet the requirements of -65°C to +165°C, and has excellent performance.

[0110] In a possible implementation, the probe assembly includes: a first strip line 320, a second strip line 330 and a probe body 310;

[0111] The first strip line 320 is welded above the needle tip of the probe body 310;

[0112] The second strip line 330 is welded below the needle tip of the probe body 310;

[0113] The first strip line 320 and the second strip line 330 are both glass substrates with gold-tin plated surfaces;

[0114] The surface areas of the first strip line 320 and the second strip line 330 are both smaller than the surface area of ​​the probe body 310 , and the front end of the probe body 310 and the rear end of the probe body 310 are respectively exposed in the sandwich formed by the first strip line 320 and the second strip line 330 .

[0115] In a possible implementation, the housing includes: a first housing 110 and a second housing 120;

[0116] The coaxial interface is fixedly arranged at the rear end of the housing, and the front end of the inner conductor 210 is connected to the rear end of the probe assembly as a whole;

[0117] The probe assembly is disposed between the second shell 120 and the first shell 110 , and the probe assembly is pressed against the front end of the shells by pressing the second shell 120 against the first shell 110 .

[0118] In a possible implementation, surfaces of the inner conductor 210 , the first shell 110 , and the second shell 120 are respectively plated with Au.

[0119] For example, in one application scenario of an embodiment of the present invention, the first strip line 320 and the second strip line 330 are processed into a size of 2.1*1.6*0.127 mm using a glass substrate, and the surface is plated with gold tin. The length and width of the two strip lines are both 1.9*0.15.

[0120] The needle tip of the probe body 310 is processed by ultraviolet photolithography micro-electroforming process.

[0121] The coaxial interface inner conductor 210 is fixed by a first supporting medium 220 and a second supporting medium 230 .

[0122] The inner conductor 210 and the first supporting medium 220 are fixed with a stainless steel screw sleeve to form a probe coaxial interface.

[0123] The first tape line 320 is precisely positioned and welded on the probe tip by CTOW eutectic welding.

[0124] The second strip line 330 is welded under the probe tip by ball planting to form a strip line + needle tip + strip line sandwich structure.

[0125] The coaxial interface is mounted on the first housing.

[0126] In the embodiment of the present invention, for the only internal interconnection solder joint, the tail of the needle tip of the probe body 310 is simulated and optimized to reduce the impedance step caused by the solder joint and reduce the discontinuity.

[0127] The needle tip of the probe body 310 in the embodiment of the present invention is manufactured by ultraviolet lithography micro-electroforming process (UV-LIGA), which has extremely high precision and repeatability.

[0128] The needle tip of the probe body 310 of the embodiment of the present invention is positioned and clamped by eutectic welding of a glass ribbon wire, which effectively ensures the spacing between the transmission needle and the ground needle and ensures the strength of the test needle tip.

[0129] In order to achieve a frequency range covering DC-67GHz, multi-level step matching and multiple dielectric constant material matching are adopted.

[0130] In order to obtain lower transmission loss, the inner conductor 210 of the radio frequency microwave probe adopts an Au electroplating solution.

[0131] In order to obtain sufficient contact force between the device under test and the probe, the probe body 310 has a needle tip, which is made of a relatively plastic nickel material, and gold is electroplated on the nickel to reduce loss.

[0132] In order to make the device under test more fully contact with the probe, the second shell is thinned and the bottom space is designed to be large enough to minimize the impact on the device under test.

[0133] In a second aspect, an embodiment of the present invention provides a method for preparing a low-discontinuity air coplanar radio frequency microwave probe, which is used to implement the low-discontinuity air coplanar radio frequency microwave probe as described in the first aspect or any possible implementation of the first aspect, and the method for preparing the low-discontinuity air coplanar radio frequency microwave probe comprises:

[0134] Processing the first strip line 320 and the second strip line 330 by thin film process;

[0135] The probe tip is precisely machined by UV-LIGA;

[0136] Electroplating Au on the inner conductor 210, the first shell and the second shell surface;

[0137] The inner conductor 210 is fixed by a first supporting medium 220 and a second supporting medium 230;

[0138] The inner conductor 210, the first supporting medium 220 and the second supporting medium 230 are fixed with a coaxial housing 240 to form a coaxial interface;

[0139] Welding the first strip line 320, the probe body 310, and the second strip line 330 into a sandwich structure;

[0140] Installing the coaxial interface in the first housing;

[0141] welding the sandwich structure to the first shell;

[0142] Welding the needle tip tail of the probe body 310 to the coaxial connector;

[0143] Welding the ground pin of the probe body 310 to the first housing;

[0144] The second housing is welded to the first housing.

[0145] In a possible implementation, welding the first strip line 320, the probe body 310, and the second strip line 330 into a sandwich structure includes:

[0146] Precisely position and weld the first strip line 320 on the probe body 310 by CTOW eutectic welding;

[0147] The second strip line 330 is welded under the probe body 310 by ball implantation.

[0148] For example, in some application scenarios, a low discontinuity air coplanar radio frequency microwave probe is manufactured by the following steps:

[0149] The first shell and the second shell are processed into designed shapes, and mounting holes are left to facilitate installation and matching with the probe locator.

[0150] The coaxial interface inner conductor 210 is precisely machined into the simulated design size by turning.

[0151] The coaxial interface inner conductor 210 is fixed to the first supporting medium 220 and the second supporting medium 230 is processed into a simulated design size using peek material.

[0152] The coaxial housing 240 is processed into a 2.4 mm-V form.

[0153] The first strip line 320 and the second strip line 330 are manufactured by thin film processing.

[0154] The tip of the probe body 310 is precisely machined by UV-LIGA.

[0155] The coaxial interface inner conductor 210, the first shell, and the second shell surface are electroplated with Au.

[0156] The coaxial inner conductor 210 is fixed by a first supporting medium 220 and a second supporting medium 230 .

[0157] The inner conductor 210 and the dielectric first dielectric support are fixed with a stainless steel screw sleeve to form a probe coaxial interface.

[0158] The first strip line 320 is precisely positioned and welded above the needle tip of the probe body 310 by CTOW eutectic welding.

[0159] The second strip line 330 is welded below the needle tip of the probe body 310 by ball planting to form a strip line + needle tip + strip line sandwich structure.

[0160] The coaxial interface is mounted on the first housing 110 .

[0161] The needle tip of the probe body 310 fixed with a strip line+needle tip+strip line sandwich structure is welded to the first shell 110 .

[0162] The tail of the probe tip and the coaxial connector are welded to each other, and the needle of the probe body 310 is welded to the first shell 110 .

[0163] The second housing 120 is welded to the first housing 110 .

[0164] In order to reduce the influence of the dielectric support column on the probe discontinuity, the low discontinuity air coplanar radio frequency microwave probe implementation method of the present invention uses the form of punching to reduce the effective dielectric constant of the supporting medium, making it closer to air and reducing discontinuity. In the implementation method of the present invention, the discontinuity capacitance introduced by the internal multi-stage broadband matching is compensated by introducing a high-resistance transmission line through simulation optimization. In the implementation method of the present invention, for the only internal interconnection solder joint, the tail of the probe body 310 needle tip is simulated and optimized to reduce the impedance step caused by the solder joint and reduce discontinuity. The needle tip of the probe body 310 of the implementation method of the present invention is made by ultraviolet lithography micro-electroforming process (UV-LIGA), which has extremely high precision and repeatability. The needle tip of the probe body 310 of the implementation method of the present invention is positioned and clamped by glass strip wire eutectic welding, which effectively ensures the spacing between the transmission needle and the ground needle and ensures the strength of the test needle tip. In order to achieve a frequency range covering DC-67GHz, multi-stage step matching and multiple dielectric constant material matching are adopted. In order to obtain lower transmission loss, the inner conductor 210 of the radio frequency microwave probe adopts the Au electroplating solution. In order to obtain sufficient contact force between the device under test and the probe, the probe body 310 has a needle tip, and the needle tip is made of nickel material with relatively strong plasticity. At the same time, gold is electroplated on the nickel to reduce loss. In order to make the device under test more fully contact with the probe, the second shell is thinned, and the bottom space is designed to be large enough to minimize the impact on the device under test.

[0165] It should be understood that the size of the serial numbers of the steps in the above implementation does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the implementation method of the present invention.

[0166] The above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A low discontinuity air coplanar radio frequency microwave probe, characterized in that: include: Housing, coaxial interface and probe assembly; The coaxial interface comprises: an inner conductor (210) and a fixing component; The inner conductor (210) is coaxially fixedly disposed inside the fixing component, and the front end of the inner conductor (210) is exposed at the front end of the fixing component; The probe assembly is fixedly arranged at the front end of the housing; The coaxial interface is fixedly arranged at the rear end of the housing, and the front end of the inner conductor (210) is integrally connected with the rear end of the probe assembly.

2. The low discontinuity air coplanar radio frequency microwave probe according to claim 1, characterized in that: The inner conductor (210) is a cylinder with at least four steps; The step diameter of the inner conductor (210) increases from front to back; The frontmost step of the inner conductor (210) is connected to the rear end of the probe assembly; The inner conductor (210) is fixedly connected to the interior of the fixing assembly via steps other than the front end step and the rear end step.

3. The low discontinuity air coplanar radio frequency microwave probe according to claim 1, characterized in that: The fixing assembly comprises: a supporting medium and a coaxial housing (240), wherein the supporting medium is an insulator and the coaxial housing (240) is a conductor; The inner conductor (210) is a cylinder, and the inner conductor (210) passes through the supporting medium and is fixedly connected to the supporting medium; The supporting medium is fixedly arranged inside the coaxial housing (240); The front end of the coaxial outer shell (240) is a cylinder, the front end of the coaxial outer shell (240) is provided with a thread, and the coaxial outer shell (240) is screwed to the housing via the thread at the front end.

4. The low discontinuity air coplanar radio frequency microwave probe according to claim 3, characterized in that: The supporting medium comprises: a first supporting medium (220) and a second supporting medium (230); The inner conductor (210) is provided with a first mounting step and a second mounting step, the diameter of the first mounting step is larger than the diameter of the second mounting step, and the first mounting step is located at the rear end of the second mounting step; The first supporting medium (220) and the second supporting medium (230) are both provided with mounting holes, the first mounting step of the inner conductor (210) is fixed through the mounting hole of the first supporting medium (220), and the second mounting step of the inner conductor (210) is fixed through the mounting hole of the second supporting medium (230); The two end surfaces of the first supporting medium (220) are provided with annular grooves, and the first supporting medium (220) is provided with holes penetrating the two end surfaces.

5. The low discontinuity air coplanar radio frequency microwave probe according to claim 4, characterized in that: The first supporting medium (220) and the second supporting medium (230) are both made of polyetheretherketone material.

6. The low discontinuity air coplanar radio frequency microwave probe according to claim 1, characterized in that: The probe assembly comprises: a first strip line (320), a second strip line (330) and a probe body (310); The first strip wire (320) is welded above the needle tip of the probe body (310); The second strip line (330) is welded below the needle tip of the probe body (310); The first strip line (320) and the second strip line (330) are both glass substrates with gold-tin plated surfaces; The surface areas of the first strip line (320) and the second strip line (330) are both smaller than the surface area of ​​the probe body (310), and the front end of the probe body (310) and the rear end of the probe body (310) are respectively exposed to the interlayer formed by the first strip line (320) and the second strip line (330).

7. The low discontinuity air coplanar radio frequency microwave probe according to any one of claims 1 to 5, characterized in that: The housing comprises: a first housing (110) and a second housing (120); The coaxial interface is fixedly arranged at the rear end of the housing, and the front end of the inner conductor (210) is connected to the rear end of the probe assembly as a whole; The probe assembly is arranged between the second shell (120) and the first shell (110), and the probe assembly is pressed against the front end of the shell by pressing the second shell (120) against the first shell (110).

8. The low discontinuity air coplanar radio frequency microwave probe according to claim 6, characterized in that: The surfaces of the inner conductor (210), the first shell (110) and the second shell (120) are respectively plated with Au.

9. A method for preparing a low discontinuity air coplanar radio frequency microwave probe, characterized in that: Used to prepare the low discontinuity air coplanar radio frequency microwave probe according to any one of claims 1 to 8, the preparation method of the low discontinuity air coplanar radio frequency microwave probe comprising: Processing the first strip line (320) and the second strip line (330) by thin film technology; The probe tip is precisely machined by UV-LIGA; Electroplating Au on the surfaces of the inner conductor (210), the first shell and the second shell; Fixing the inner conductor (210) with a first supporting medium (220) and a second supporting medium (230); The inner conductor (210), the first supporting medium (220) and the second supporting medium (230) are fixed with a coaxial housing (240) to form a coaxial interface; Welding the first strip line (320), the probe body (310), and the second strip line (330) into a sandwich structure; Mounting the coaxial interface on the first housing; welding the sandwich structure to the first shell; Welding the needle tip tail of the probe body (310) to the coaxial joint; welding the ground pin of the probe body (310) to the first housing; The second housing is welded to the first housing.

10. The method for preparing a low discontinuity air coplanar radio frequency microwave probe according to claim 9, characterized in that: The step of welding the first strip line (320), the probe body (310) and the second strip line (330) into a sandwich structure comprises: Precisely positioning and welding the first strip wire (320) on the probe body (310) by CTOW eutectic welding; The second strip line (330) is welded below the probe body (310) by ball implantation.

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