Microwave circuit fine tuning probe and preparation method thereof

Abstract

The invention discloses a microwave circuit fine tuning probe and a preparation method thereof, the probe comprises an insulating needle body and a debugging metal layer arranged at the end part of the insulating needle body, the side wall of the end part of the insulating needle body is a smooth surface layer, and the smooth surface layer is formed by polishing side wall ridges. The probe is simple in structure, the contact position and the contact amount of the debugging metal layer and the to-be-debugged structure are flexible and controllable, the debugging accuracy is improved, the probe can be used for verification fine debugging of a microwave circuit, prediction of the optimization and improvement direction of a circuit structure is achieved, the microwave circuit can be prevented from being damaged in the debugging process, and the debugging efficiency is improved. A plurality of mature process steps are combined together, so that the formed debugging metal layer is good in uniformity, strong in adhesive force, resistant to abrasion, suitable for debugging operation of a microwave circuit and high in reliability.

Description

Technical Field

[0001] The invention belongs to the technical field of microwave debugging, and in particular relates to a microwave circuit fine-tuning probe and a preparation method thereof. Background Art

[0002] Due to device performance fluctuations, simulation design limitations and assembly deviations, there may be a certain gap between the measured values ​​and design indicators of microwave integrated circuit performance parameters. In order to optimize the circuit structure, improve the performance of microwave products and avoid repeated processing and verification, it is necessary to debug the line width of the transmission line (microstrip line, coplanar waveguide, etc.), the effective physical length of the filter resonant unit, the resistance value of the attenuator equivalent circuit, the matching branches of different cascade structures, and the resistance value of the active device voltage divider module.

[0003] However, the current debugging devices are prone to damage the microstrip circuit, and the debugging accuracy and reliability are poor. For example, Chinese utility model patent CN205050969U discloses a microwave debugging handle for a microstrip circuit. A copper sheet is fixed to the end of a polytetrafluoroethylene handle with 502 glue to obtain a debugging handle for debugging the radio frequency impedance of the microstrip circuit. On the one hand, it can only be used for impedance debugging of microstrip circuits, and its application field is narrow. On the other hand, the thin copper sheet is glued to the end of the handle with 502 glue, and the adhesion and flatness cannot be guaranteed. The copper sheet is easily oxidized and falls off, which can easily cause damage to the microstrip circuit. It has a single size, poor debugging accuracy and reliability, and cannot achieve fine debugging of different circuit structures. Therefore, there is an urgent need for a tool that can verify, nearly damage-free, and finely debug microwave circuits. Summary of the invention

[0004] The purpose of the present invention is to provide a microwave circuit fine-tuning probe and a preparation method thereof in order to overcome the defects of the prior art. The probe has a simple structure, and the contact position and contact amount between the debugging metal layer and the structure to be debugged are flexible and controllable. It can be used for verifying fine debugging of microwave circuits, realizing the prediction of the direction of circuit structure optimization and improvement, and avoiding damage to the microwave circuit during the debugging process.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A microwave circuit fine-tuning probe comprises an insulating needle body and a debugging metal layer arranged at the end of the insulating needle body. The end side wall of the insulating needle body is a smooth surface layer, and the smooth surface layer is formed by grinding the side wall ridge line.

[0007] In one embodiment, debugging metal layers are provided at both ends of the insulating needle body, and the widths of the two ends of the insulating needle body are inconsistent. The width of the insulating needle body changes uniformly along its axis. Through this embodiment, debugging metal layers with inconsistent widths are formed at both ends of the insulating needle to be compatible with precise debugging of microwave circuit structures of different sizes. For example, the narrower end can be used for debugging of small-size structures, and the wider end can be used for debugging of large-size structures.

[0008] In one embodiment, a clamping protection structure is also provided on the insulating needle body, and both ends of the insulating needle body are located outside the clamping protection structure. Through this embodiment, on the one hand, the insulating needle body is reinforced and protected to extend its service life, and on the other hand, it is convenient for the operator to hold it for operation.

[0009] In one embodiment, the clamping protection structure includes multiple layers of heat shrinkable tubes sequentially sleeved on the insulating needle body. Through this embodiment, the property of the heat shrinkable tubes to shrink when exposed to heat is utilized so that the heat shrinkable tubes are tightly wrapped around the insulating needle body through heat shrinkage, even if the clamping protection structure is firmly set on the insulating needle body, and the heat shrinkable tubes are insulating plastic tubes.

[0010] In one embodiment, the lengths of the multiple layers of heat shrink tubes increase layer by layer from the inside to the outside. Through this embodiment, the clamping protection structure can be more firmly wrapped on the insulating pin body.

[0011] The present invention also provides a method for preparing a microwave circuit fine-tuning probe, which is used to prepare the microwave circuit fine-tuning probe, comprising the following steps:

[0012] Step S1, grinding the sidewall ridges at the ends of the insulating substrate along the length or width direction to form a smooth surface layer;

[0013] Step S2, preparing a debugging metal layer on the polished side wall of the insulating substrate;

[0014] Step S3, starting from the side wall where the metal layer of the insulating substrate is located, cutting obliquely along the surface perpendicular to the insulating substrate to obtain insulating needles with inconsistent widths at both ends;

[0015] Step S4, a clamping protection structure is sleeved on the insulating needle, and the debugging metal layers at both ends of the insulating needle are located outside the clamping protection structure;

[0016] In one embodiment, in step S2, preparing the debugging metal layer includes:

[0017] Step S201, magnetron sputtering, so that the target material forms a conductive film on the surface and side wall of the insulating substrate;

[0018] Step S202, pasting a dry film on the conductive film on the surface of the insulating substrate;

[0019] Step S203, selective electroplating to thicken the conductive film on the side wall of the insulating substrate;

[0020] Step S204, removing the dry film on the insulating substrate;

[0021] Step S205 , etching to remove the conductive film on the insulating substrate to leave a uniform debugging metal layer on the side wall of the insulating substrate.

[0022] In one embodiment, in step S4, a clamping protection structure is sleeved on the insulating needle, comprising:

[0023] A heat shrink tube is sleeved on the insulating needle, and both ends of the insulating needle are located outside the heat shrink tube. The heat shrink tube is shrunk by high-temperature baking and attached to the insulating needle. Multiple layers of heat shrink tubes are sequentially sleeved and heat-shrunk to form a clamping protection structure.

[0024] In one embodiment, it further comprises:

[0025] In the process of sequentially baking each layer of the heat shrink tube at high temperature, the length of the heat shrink tube is increased layer by layer.

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

[0027] (1) The probe provided has a simple structure and can be used for verification and fine debugging of microwave circuits, realizing the prediction of the direction of circuit structure optimization and improvement, and avoiding damage to the microwave circuit during the debugging process;

[0028] (2) A debugging metal layer is formed by a sputtering-dry film-selective electroplating-dry film removal-etching process, and the formed debugging metal layer has good uniformity, strong adhesion and wear resistance;

[0029] (3) The debugging metal layers at both ends of the probe have different sizes, which can be compatible with the precise debugging of microwave circuit structures of different sizes;

[0030] (4) The placement of the debug probe and the contact amount between the debug metal layer and the structure to be debugged are flexible and controllable, which can achieve fine debugging;

[0031] (5) Multiple layers of heat shrink tubing are sequentially sleeved and heat-shrunk on the insulating needle body, and the length of the heat shrink tubing increases layer by layer, which not only reinforces and protects the insulating needle and improves the mechanical strength of the probe, but also facilitates handheld operation and prolongs its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings, wherein:

[0033] Figure 1 A schematic diagram showing the structure of the fine-tuning probe of the present invention is shown;

[0034] Figure 2 A schematic diagram showing the structure of the insulating needle of the present invention is shown;

[0035] Figure 3 Shows Figure 2 A magnified view of the local structure at point A in the middle;

[0036] Figure 4 A schematic diagram showing the end structure of the insulating substrate of the present invention after being polished;

[0037] Figure 5 It shows a schematic structural diagram of the insulating substrate end portion after a metal adjustment layer is prepared in the present invention;

[0038] Figure 6 A schematic diagram showing the working application of the probe of the present invention for debugging the line width of a transmission line in a microwave product;

[0039] In the drawings, the same reference numerals are used for the same components, but the drawings are not drawn to scale.

[0040] Reference numerals:

[0041] 1-insulating substrate, 2-debugging metal layer, 3-insulating needle body, 4-heat shrink tube, 5-debugging probe, 6-transmission line, 7-microwave product. DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with the accompanying drawings.

[0043] Example 1

[0044] The present invention provides a microwave circuit fine-tuning probe, such as Figure 2 and Figure 3 As shown, it includes an insulating needle body 3 and a debugging metal layer 2 arranged at the end of the insulating needle body 3, and the end side wall of the insulating needle body 3 is a smooth surface layer, and the smooth surface layer is formed by grinding the side wall edge line;

[0045] It should be noted that Figure 2 The schematic diagram of the structure of the insulating needle composed of the debugging metal layer 2 and the insulating needle body 3 is shown. Figure 3 The schematic diagram of the structure of the debugging metal layer 2 at the end of the insulating needle is enlarged and shown. The insulating needle has a simple structure, and the contact position and contact amount of the debugging metal layer 2 on it and the structure to be debugged are flexible and controllable, which can be used for verifying fine debugging of microwave circuits and realizing the prediction of the direction of circuit structure optimization and improvement. The edge line of the end side wall of the insulating needle body 3 is polished to form a smooth surface layer, so that the microwave circuit can be avoided from being damaged during the debugging process;

[0046] Furthermore, both ends of the insulating needle body 3 are provided with a debugging metal layer 2, and the widths of the two ends of the insulating needle body 3 are inconsistent, and the width of the insulating needle body 3 changes uniformly along its axis;

[0047] It should be noted that debugging metal layers 2 with inconsistent widths are provided at both ends of the insulating needle body 3 to accommodate accurate debugging of microwave circuit structures of different sizes, such as the narrower end can be used for debugging of small-size structures, and the wider end can be used for debugging of large-size structures;

[0048] Furthermore, a clamping protection structure is also provided on the insulating needle body 3, and both ends of the insulating needle body 3 are located outside the clamping protection structure, which not only reinforces and protects the insulating needle body 3, improves the mechanical strength of the probe, prolongs its service life, but also facilitates handheld operation;

[0049] Specifically, Figure 1 As shown, the clamping protection structure includes a multi-layer heat shrink tube 4 which is sequentially sleeved on the insulating needle body 3. The heat shrink tube 4 shrinks when heated so that it is tightly wrapped on the insulating needle body 3 through heat shrinkage, that is, the clamping protection structure is firmly arranged on the insulating needle body 3, and the heat shrink tube 4 is an insulating plastic tube;

[0050] Furthermore, the length of the multi-layer heat shrink tube 4 increases layer by layer from the inside to the outside, which not only enables the clamping protection structure to be more firmly wrapped on the insulating needle body 3, but also reduces the stress on the exposed end of the insulating needle.

[0051] Example 2

[0052] The present invention also provides a method for preparing a microwave circuit fine-tuning probe, which is characterized by comprising the following steps:

[0053] Step S1, grinding the sidewall ridges at the ends of the insulating substrate along the length or width direction to form a smooth surface layer;

[0054] Step S2, preparing a debugging metal layer on the polished side wall of the insulating substrate, comprising:

[0055] Step S201, magnetron sputtering, so that the target material forms a conductive film on the surface and side wall of the insulating substrate;

[0056] Step S202, pasting a dry film on the conductive film on the surface of the insulating substrate;

[0057] Step S203, selective electroplating to thicken the conductive film on the side wall of the insulating substrate;

[0058] Step S204, removing the dry film on the insulating substrate;

[0059] Step S205: etching to remove the conductive film on the insulating substrate to leave a uniform debugging metal layer on the side wall of the insulating substrate;

[0060] Step S3, starting from the side wall where the metal layer of the insulating substrate is located, cutting obliquely along the surface perpendicular to the insulating substrate to obtain insulating needles with inconsistent widths at both ends;

[0061] Step S4: a clamping protection structure is set on the insulating needle, and the debugging metal layers at both ends of the insulating needle are located outside the clamping protection structure.

[0062] Wherein, in step S4, setting the clamping protection structure includes:

[0063] A heat shrink tube is placed on the insulating needle, and both ends of the insulating needle are located outside the heat shrink tube. The heat shrink tube is shrunk by high-temperature baking and attached to the insulating needle. Multiple layers of heat shrink tubes are sequentially placed and heat-shrunk to form a clamping protection structure. During the process of sequentially baking each layer of heat shrink tube at high temperature, the length of the heat shrink tube is gradually increased.

[0064] It should be noted that in step S1, the insulating substrate is a substrate material with excellent insulating properties, such as ceramic, glass, quartz, etc., and the edge line of the end side wall of the insulating substrate is polished along the length or width direction of the insulating substrate, such as Figure 4 As shown, the end of the insulating substrate 1 is formed into a smooth surface layer, which can prevent the edge line of the end of the insulating needle from being too heavily indented during the debugging process and thus damaging the microwave circuit;

[0065] In step S2, the process steps of sputtering-dry film-selective electroplating-dry film removal-etching are adopted, such as Figure 5 As shown, a debugging metal layer 2 is formed at the end of the insulating substrate 1. Each process step in step S2 is a mature process, which is convenient for mass production. In this embodiment, the above-mentioned multiple process steps are combined together to make the formed debugging metal layer have good uniformity, strong adhesion and wear resistance, which is suitable for the debugging operation of the microwave circuit, has high reliability, improves the debugging accuracy, and is not easy to damage the microwave circuit;

[0066] In step S3, a debugging metal layer with inconsistent width is formed to be compatible with precise debugging of microwave circuit structures of different sizes. For example, the narrower end can be used for debugging of small-sized structures, and the wider end can be used for debugging of large-sized structures. In the process of cutting, the insulating substrate can be cut obliquely along the length direction to obtain a longer insulating needle, or the insulating substrate can be cut obliquely along the width direction to obtain a shorter insulating needle. Cutting can be performed according to actual needs. After step S3, an insulating needle composed of an insulating needle body and a debugging metal layer can be obtained, which can be used for verification and fine debugging of microwave circuits.

[0067] In step S4, the heat shrinkable tube is tightly wrapped around the insulating needle body by heat shrinkage, so that the clamping protection structure is firmly set on the insulating needle body to reinforce the insulating needle. After step S4, the insulating needle obtained in step S3 and the clamping protection structure together form the following structure: Figure 1 The fine-tuning probe shown can effectively improve the mechanical strength of the insulating needle, extend its service life, facilitate handheld operation, and increase the length of the heat shrink tube layer by layer from the inside to the outside to reduce the stress on the exposed end of the probe.

[0068] Example 3

[0069] Different from Example 2, this example provides a specific probe preparation process, including the following steps:

[0070] Step S1, grinding the edge lines of the end side walls of the thin film ceramic plate of 50mm*45mm*0.7mm in the length direction to be smooth;

[0071] Step S2, preparing a debugging gold layer of about 10 μm thick at both ends of the ceramic plate in the length direction;

[0072] Step S3, using a grinding wheel cutting method, starting from the side wall where the gold layer is located, cutting along its length direction, perpendicular to the surface of the ceramic plate, to obtain a ceramic needle with a length of 50 mm, a width of 0.8 mm at one end, and a width of 1.1 mm at the other end;

[0073] Step S4, put a transparent flame-retardant heat shrink tube on the ceramic needle, keep both ends of the ceramic needle exposed, and bake it with hot air at 200°C to shrink the heat shrink tube and closely adhere to the ceramic needle body. Repeat the installation and heat shrinkage of the heat shrink tube three times, and the length of each layer of heat shrink tube increases by 1 to 2m, forming a heat shrink tube protection structure with a wall thickness of about 0.9mm, and obtaining a microwave circuit fine-tuning probe, such as Figure 1 shown.

[0074] It should be noted that the type of insulating substrate, the thickness and type of the adjustment metal layer, the size of the insulating pin, the type of heat shrink tube, the arrangement of the heat shrink tube and the number of heat shrinkage times can all be adjusted according to actual needs.

[0075] Specifically, the debugging probe 5 prepared in this embodiment is used in debugging the transmission line width of microwave products. Figure 6 As shown, the debugging probe 5 is held in hand to make the debugging metal layer 2 at the end contact with the transmission line 6 in the microwave product 7, and the contact position and contact amount between the debugging metal layer 2 and the transmission line 6 are continuously adjusted, and the changing trend of the signal curve on the test instrument is observed to complete the verification debugging of the widening or narrowing of the transmission line. The contact position and contact amount between the debugging metal layer 2 and the transmission line 6 are flexibly controllable.

[0076] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "bottom", "top", "front", "back", "inside", "outside", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0077] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the features of the various dependent claims and herein may be combined in a manner different from that described in the original claims. It should also be understood that the features described in conjunction with the individual embodiments may be used in other embodiments.

Claims

1. A microwave circuit fine-tuning probe, characterized in that: It comprises an insulating needle body and a debugging metal layer arranged at the end of the insulating needle body. The end side wall of the insulating needle body is a smooth surface layer, and the smooth surface layer is formed by grinding the side wall edge line.

2. A microwave circuit fine-tuning probe according to claim 1, characterized in that: Both ends of the insulating needle body are provided with adjustment metal layers, and the widths of the two ends of the insulating needle body are inconsistent, and the width of the insulating needle body changes uniformly along its axis.

3. The microwave circuit fine-tuning probe according to claim 1, characterized in that: The insulating needle body is also provided with a clamping protection structure, and both ends of the insulating needle body are located outside the clamping protection structure.

4. A microwave circuit fine-tuning probe according to claim 3, characterized in that: The clamping protection structure includes multiple layers of heat shrinkable tubes which are sequentially sleeved on the insulating pin body.

5. A microwave circuit fine-tuning probe according to claim 4, characterized in that: The lengths of the multiple layers of heat shrinkable tubes increase layer by layer from the inside to the outside.

6. A method for preparing a microwave circuit fine-tuning probe, used for preparing the microwave circuit fine-tuning probe as claimed in any one of claims 1 to 5, characterized in that: The steps include: Step S1, grinding the sidewall ridges at the ends of the insulating substrate along the length or width direction to form a smooth surface layer; Step S2, preparing a debugging metal layer on the polished side wall of the insulating substrate; Step S3, starting from the side wall where the metal layer of the insulating substrate is located, cutting obliquely along the surface perpendicular to the insulating substrate to obtain insulating needles with inconsistent widths at both ends; Step S4, a clamping protection structure is sleeved on the insulating needle, and the adjustment metal layers at both ends of the insulating needle are located outside the clamping protection structure.

7. The method for preparing a microwave circuit fine-tuning probe according to claim 6, characterized in that: In step S2, preparing the debugging metal layer includes: Step S201, magnetron sputtering, so that the target material forms a conductive film on the surface and side wall of the insulating substrate; Step S202, pasting a dry film on the conductive film on the surface of the insulating substrate; Step S203, selective electroplating to thicken the conductive film on the side wall of the insulating substrate; Step S204, removing the dry film on the insulating substrate; Step S205 , etching to remove the conductive film on the insulating substrate to leave a uniform debugging metal layer on the side wall of the insulating substrate.

8. The method for preparing a microwave circuit fine-tuning probe according to claim 6, characterized in that: In step S4, a clamping protection structure is sleeved on the insulating needle, including: A heat shrink tube is sleeved on the insulating needle, and both ends of the insulating needle are located outside the heat shrink tube. The heat shrink tube is shrunk by high-temperature baking and attached to the insulating needle. Multiple layers of heat shrink tubes are sequentially sleeved and heat-shrunk to form a clamping protection structure.

9. The method for preparing a microwave circuit fine-tuning probe according to claim 8, characterized in that: Also includes: In the process of sequentially baking each layer of the heat shrink tube at high temperature, the length of the heat shrink tube is increased layer by layer.

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