A method for manufacturing a curved conformal antenna based on composite micro-nano additive manufacturing

Abstract

The present invention discloses a manufacturing method of a curved conformal antenna based on composite micro-nano additive manufacturing, including substrate pretreatment, printing a conformal antenna structure seed layer using a five-axis linkage electric field driven jet deposition micro-nano 3D printer based on an extraction electrode, conductive treatment of the printed conformal antenna structure seed layer, micro-electroforming or chemical plating of the conformal antenna structure, sample post-processing and the like. The method of the present invention is used to realize high-efficiency and low-cost batch manufacturing of large-size high-precision curved conformal antennas, especially to realize the manufacturing of large-size transparent curved conformal antennas, and the manufactured conformal antennas have the advantages of high precision, low profile, miniaturization, and ultra-wideband. In particular, it can realize the high-efficiency and low-cost manufacturing of large-size seeker missile-borne transparent curved conformal antennas, fighter aircraft-borne transparent curved conformal antennas, and optical instrument surface transparent curved conformal antennas.

Description

Technical Field

[0001] The present invention belongs to the field of micro-nano additive manufacturing and conformal antenna technology, and specifically relates to a method for efficiently and cheaply manufacturing large-size curved conformal antennas based on composite micro-nano additive manufacturing technology, and in particular to a method for highly precise and cheaply manufacturing transparent curved conformal antennas. Background Art

[0002] Conformal antennas (conformal array antennas) are antenna arrays that are consistent with the shape of the carrier platform and reduce the carrier load. In modern wireless communication systems, conformal antennas can conform to the surface of high-speed carrier platforms such as aircraft, missiles and satellites, and do not destroy the carrier's shape structure and aerodynamic characteristics. They have become a research hotspot and cutting-edge technology in the field of wireless communication antennas. Compared with planar array antennas, curved conformal antennas have greater advantages, mainly including: conformal antennas can be installed on surfaces of different curvatures of aircraft and aerospace equipment such as aircraft, missiles, drones, satellites, etc., and will not destroy the aerodynamic shape of aircraft and aerospace equipment like traditional antennas, so that the platform maintains a good aerodynamic layout and stealth characteristics; conformal antennas attached to the surface of the fuselage or directly made into skins can scan and detect targets in a larger airspace and distance, greatly improving the effectiveness of electronic attacks. Conformal antennas are small in size, light in weight, and do not occupy space inside the aircraft. They completely change the situation where the antenna protrudes from the surface of the weapon, and achieve an integrated design of the antenna and the fuselage, thereby maximizing the stealth characteristics and maneuverability of fighters and warships, thereby greatly improving the combat effectiveness.

[0003] In the airborne intelligent skin antenna technology, detection elements, microprocessor systems and drive elements are implanted in the shells of spacecraft, aircraft, drones, warships, submarines and other equipment, so that the shells of these equipment not only play the role of structural parts, but also have excellent aerodynamic, stealth, surveillance, early warning and communication performance. In the field of high-performance missiles, conformal antenna technology is adopted to integrate the antenna with the missile wall, missile wing and even the radome, making full use of the carrier surface area to increase the antenna caliber and improve the antenna gain. The radome design can give priority to the performance of the narrowband antenna in the hood, reduce the design difficulty of the radome, reduce the impact on the ground performance, and at the same time reduce the radar cross section (RCS) of the seeker carrier. Conformal antenna technology can greatly improve the survivability and combat effectiveness of missiles and is one of the key technologies used in the new generation of guided weapons. In transparent conformal antenna technology, a transparent conformal antenna can be installed on the surface of the seeker, and the internal space is left for other sensors. The conformal antenna of the seeker reduces the volume and weight of the missile body, realizes rapid and accurate tracking of multiple targets, and can also improve anti-interference and stealth performance. In addition, the manufacture of transparent conformal antennas based on transparent curved substrates has very broad application prospects in many fields such as sixth-generation fighter jets, military aerospace communications, intelligent drones, and autonomous driving.

[0004] At present, the main manufacturing methods of conformal antennas and conformal array antennas include printing, transfer printing, laser direct writing technology, holographic lithography technology, etc. Although these technologies can realize the manufacture of curved conformal antennas, these existing technologies all have serious shortcomings and limitations. Printing technology, as a non-contact printing method, reduces the restrictions on the shape and structure of the substrate (substrate), and does not require molds or masks, etc., has good material compatibility, and is more flexible in the process. However, there are still the following problems, such as traditional inkjet printing, low printing accuracy (the current minimum line width is 20 microns), limited printing materials (the viscosity of the material is less than 30mPa.s), and poor adhesion to the substrate. Extrusion printing has low printing resolution, and the current line width is generally 100 microns, which is difficult to meet the actual needs of high-performance conformal antennas, especially transparent conformal antennas; aerosol printing is currently the most mature solution for realizing curved conformal printing technology, but the equipment is currently expensive and the cost is high, especially the printing materials are limited (the printing materials must be atomized), and the minimum width of the printed line is currently 10 microns; in addition, the intellectual property rights of this technology are in the United States Optomec Company, and its development is subject to greater restrictions. Transfer technology uses a donor substrate to complete the production of a conductive film, and transfers the functional structure to the target substrate with the help of a flexible transfer stamp. It has the advantages of simple process and low cost, and has good application prospects in the integration of flexible and conformal transparent antennas. However, the main shortcomings are that the mold manufacturing process is complex, the precision is poor, the efficiency is relatively low, and it is very difficult for non-closed surfaces, especially arbitrary surfaces. Holographic lithography does not require a complex optical system and a traditional optical mask, and can effectively eliminate the broadening of diffraction lines when patterning on a non-planar substrate. It has high resolution and uniformity, and has received widespread attention in the manufacture of conformal antennas. Holographic lithography is limited by the substrate morphology, with poor process flexibility, long cycle, and low processing accuracy. Laser micromachining technology directly digitally manufactures various structures onto the curved surface through laser irradiation. All characteristic dimensions of the functional structure can be adjusted with the help of computer control, and the process flow is simple. Laser processing requires the substrate material carrying the circuit pattern to withstand high temperature and activation, which limits the range of materials that can be selected. It is difficult to evenly coat large-size curved surfaces and large average curvature substrates, and the material waste is relatively serious, and the processing accuracy is low.

[0005] Based on the above introduction, there is an urgent need for a manufacturing method that can solve the problem of efficient and low-cost manufacturing of large-size, high-precision conformal antennas (especially transparent curved conformal antennas), and overcome the difficulty that existing technologies cannot realize the manufacturing of high-precision conformal antennas on large-format, large-curvature curved carriers (especially the manufacturing of conformal transparent antennas with line widths below 10 microns and large aspect ratio structures). Summary of the invention

[0006] In order to overcome the shortcomings of the existing technology, the high-efficiency and low-cost batch manufacturing of large-sized high-precision curved conformal antennas can be realized, especially the manufacturing of large-sized transparent curved conformal antennas, and the manufactured conformal antennas have the advantages of high precision, low profile, miniaturization, and ultra-wideband. In particular, it can realize the efficient and low-cost manufacturing of large-sized transparent curved conformal antennas on seeker missiles, transparent curved conformal antennas on fighter aircraft (UAVs, fighters, early warning aircraft, etc.), and transparent curved conformal antennas on the surface of optical instruments.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A method for manufacturing a curved conformal antenna based on composite micro-nano additive manufacturing mainly includes the following process steps:

[0009] Step 1: Substrate pretreatment: The curved substrate is subjected to hydrophobic treatment, which includes decontamination, cleaning, surface hydrophobicity and drying. Specifically, first, the curved substrate surface is decontaminated and cleaned; then the surface is subjected to surface hydrophobic treatment to reduce its surface energy and improve the stability, consistency and high precision of printing; finally, drying and air drying are performed.

[0010] Step 2: Printing of seed layer of conformal antenna structure: Use a five-axis linkage electric field driven jet curved surface conformal micro-nano 3D printer to print the seed layer of conformal antenna structure, i.e. conductive layer, on the curved surface substrate. During the printing process, laser or UV lamp is used for in-situ curing and sintering to achieve simultaneous printing and sintering. Combine different printing modes and change different printing process parameters to achieve printing of seed layers with different line widths and precision. High-viscosity nano-conductive silver paste with a solid content of more than 70% is preferred as the printing material. The line width is 0.5μm-200μm.

[0011] Step 3: Conductive treatment of the printed conformal antenna structure seed layer: The conformal antenna structure seed layer substrate printed in step 2 is placed in a vacuum box for sintering and conductive treatment, followed by cleaning and nitrogen drying to completely remove dirt on the seed layer and substrate.

[0012] Step 4: Micro-electroforming or chemical plating of conformal antenna structure: The conformal antenna structure seed layer printed in step 3 is subjected to electroforming or chemical plating process, and metal material is further deposited on the seed layer. The thickness of the deposited metal material is 3 microns to 20 microns.

[0013] Step 5: Sample post-processing: Clean the micro-electroforming or chemically plated samples to remove the residues produced during the deposition process, and then dry the samples to prepare a large-size, high-precision curved conformal antenna.

[0014] As a further limitation, the curved substrate in step 1 can be a hemisphere, a cylinder, a cone, a parabola, an arbitrary curved surface, etc., or it can be a 3D substrate or an arbitrary curved surface substrate produced by cutting, molding, or 3D printing.

[0015] As a further limitation, the curved conformal antenna printing device in step 2 is a five-axis linkage electric field driven jet deposition micro-nano 3D printer based on extraction electrodes, which can complete five-degree-of-freedom printing in the X, Y, Z, A, and C directions, and can better realize the printing of conformal antenna patterns by adjusting the rotation angle of the rotating worktable.

[0016] As a further limitation, the printing material used for printing the conformal antenna seed layer in step 2 is a high-viscosity nano silver paste, a solution of metals such as nano nickel / silver, a modified liquid metal, and other conductive materials that adhere well to the substrate.

[0017] As a further limitation, the printing nozzle used in step 2 is a glass needle (glass sprayed with gold for conductive treatment) with an inner diameter ranging from 1 to 300 μm, a stainless steel nozzle, or a Musashi needle.

[0018] As a further limitation, the printing path of the conformal antenna in step 2 can generate corresponding processing codes according to the shape of different curved substrates, and be imported into the machine system to coordinately adjust different printing process parameters to complete the printing of conformal antennas with different line widths (0.5-200μm) and different printing speeds (1-200mm / s).

[0019] As a further limitation, the degree of conformality in step 2 depends on the distance and direction between the nozzle and the curved substrate remaining the same, that is, the distance is always within the range allowed by the accuracy, and the direction is always printed vertically along the normal direction of the curved substrate.

[0020] As a further limitation, the printing process parameter ranges in step 2 are: applied voltage is 100V-2000V, air pressure is 30-200kPa, printing speed is 1-100mm / s, and nozzle diameter is 1-300μm.

[0021] As a further limitation, the conductive treatment process of the conformal antenna in step 2 is to place the conductive silver paste under a laser sintering machine at 150°C for simultaneous curing and sintering with printing based on the optimal curing process conditions of the conductive silver paste used, so as to prevent the printed material from diffusing on the substrate and improve the printing accuracy and efficiency.

[0022] As a further limitation, the laser in step 2 is a fine-point laser with a spot diameter of less than 0.1 mm, which is beneficial to improving the curing effect.

[0023] As a further limitation, the laser and the nozzle in step 2 are fixed at the same time, a certain distance and direction are designed, and the printing path should be completely consistent to achieve synchronous curing and sintering after printing.

[0024] As a further limitation, the cleaning solvent selected in step 3 is required not to react with the conductive silver paste and the curved substrate, remove surface pollutants, and improve the smoothness of the conductive layer surface.

[0025] Furthermore, in the electroforming process in step 4, firstly, the reagent materials required for the electroforming solution are weighed in a certain proportion, and then they are fully dissolved in sequence to finally obtain the required electroforming solution, and the pH value of the solution is adjusted within the range of 3-4.5.

[0026] Furthermore, in the chemical plating process of the magnetic conductive layer in step 4, firstly, the reagent materials required for the chemical plating solution are weighed in a certain proportion, and then they are fully dissolved in sequence to finally obtain the required chemical plating solution, and the pH value of the solution is adjusted within the range of 3-4.5.

[0027] As a further limitation, in the micro-electroforming process in step 4, a conductive copper tape is attached to one side of the conductive layer of the conformal antenna and connected to the cathode of the precision micro-electroforming equipment. The metal plate is connected to the anode and placed in the electroforming liquid, waiting for the solution to undergo a chemical reaction to deposit a layer of nickel on the surface of the conductive layer.

[0028] As a further limitation, the height of the micro-electroforming in step 4 can be adjusted according to the concentration of the nickel solution and the electroforming time to achieve the desired height effect.

[0029] As a further limitation, in the electroforming process in step 4, a constant temperature monitoring system and a solution circulation system are used to control the temperature of the electroforming liquid in real time to ensure that the temperature of the electroforming liquid is always within 45-55°C, and the solution circulation speed in the solution circulation system is 1-2m / s.

[0030] As a further limitation, in the electroforming process in step 4, an ultrasonic vibrator is added to the electroforming solution to quickly discharge bubbles from the electrode surface to reduce concentration polarization and improve flow field characteristics.

[0031] As a further limitation, in the step 5, the drying temperature range of the sample post-processing is 80-90° C., and the cleaning agent should be a chemical reagent that does not affect the sample.

[0032] As a further limitation, the curved conformal antenna substrate is not limited to a spherical surface, a hemispherical surface, a cylindrical surface, etc., and can be any free-form surface shape.

[0033] As a further limitation, the micro-electroforming material is not limited to one or two or more alloy materials of nickel, chromium, titanium and copper.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The present invention combines the five-axis linkage electric field driven jet deposition curved surface conformal micro-nano 3D printing technology and the micro-electroforming process to achieve efficient and low-cost manufacturing of large-scale curved surface conformal antennas, especially the manufacturing of large-scale conformal antennas with complex 3D structures and arbitrarily complex surfaces.

[0036] (2) The synchronous laser sintering technology is used to achieve the synchronous sintering and solidification of the printed conformal antenna seed layer, preventing the printing material from flowing in the substrate and improving the printing efficiency.

[0037] (3) The present invention adopts a five-axis linkage electric field driven jet deposition curved surface conformal micro-nano 3D printing technology based on extraction electrodes, which can effectively improve the printing resolution so that the printed curved surface conformal antenna can reach sub-micron level accuracy.

[0038] (4) The five-axis linkage electric field driven jet deposition curved surface conformal micro-nano 3D printing technology can realize five-degree-of-freedom 3D printing, and can print complex curved surface conformal antennas. By adjusting the AC axis rotation angle, the printing freedom and efficiency can be achieved.

[0039] (5) The micro-electroplating process can achieve high-precision printing of two-layer or multi-layer conformal antenna structures.

[0040] (6) It can realize the manufacture of transparent curved conformal antennas on seeker missiles, transparent curved conformal antennas on fighter aircraft (UAVs, fighter jets, early warning aircraft, etc.), and transparent curved conformal antennas on the surface of optical instruments, and has a wide range of applications.

[0041] (7) The production cost is low, the efficiency is high, and the printed conformal antenna is of high precision.

[0042] (8) The present invention is based on composite micro-nano additive manufacturing, with high material utilization and low cost.

[0043] (9) The production of the present invention is carried out at normal temperature, normal pressure and room temperature, and has low requirements on the production environment.

[0044] (10) The present invention is suitable for various substrates, belongs to non-contact printing, and causes almost no damage to the substrate.

[0045] (11) The conformal antenna manufactured by the present invention has the advantages of simple process, short production process, high efficiency, low cost, green and good flexibility;

[0046] (12) Combined with 3D printing such as extrusion and injection, the present invention can also realize the integrated manufacturing of conformal antenna substrate and conductive structure.

[0047] (13) It is possible to manufacture multi-layer curved conformal antennas. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present application. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0049] Figure 1 Schematic diagram of the curved conformal antenna structure;

[0050] Figure 2 Schematic diagram of the manufacturing process of curved conformal antenna;

[0051] Figure 3 Schematic diagram of the manufacturing process of curved conformal antenna;

[0052] Figure 4 Schematic diagram of the structure of five-axis linkage electric field driven spray deposition surface conformal micro-nano 3D printing based on extraction electrode;

[0053] Figure 5 Schematic diagram of micro-electroforming principle;

[0054] Among them, 1-X axis, 2-Y axis, 3-Z axis, 4-A axis, 5-C axis, 6-high voltage power supply, 7-CCD camera, 8-hemispherical glass substrate, 9-conformal antenna, 10-nozzle module, 11-fiber laser. DETAILED DESCRIPTION

[0055] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0056] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0057] The present invention will be further described below in conjunction with embodiments

[0058] Example 1

[0059] In this embodiment, nano-conductive silver paste is used as the printing material. First, a metal conformal antenna seed layer structure is printed on a curved substrate using a five-axis linkage electric field-driven jet deposition curved conformal micro-nano 3D printing technology based on an extraction electrode; the printed metal conformal antenna seed layer structure is then subjected to a low-temperature sintering and conductive treatment; subsequently, the metal conformal antenna seed layer structure after the conductive treatment is subjected to precision micro-electroforming, and metal nickel or silver is deposited on the silver surface of the metal conformal antenna seed layer; finally, the electroformed sample is cleaned and dried to complete the manufacture of the curved conformal antenna.

[0060] The specific process steps of the method for manufacturing a glass cylindrical conformal antenna based on composite micro-nano additive manufacturing in this embodiment are as follows:

[0061] Step 1: Pre-treat the substrate

[0062] Cleaning, hydrophobicity and drying of cylindrical curved glass substrates. First, the surface of the curved glass substrate is cleaned and decontaminated; then the glass surface is hydrophobicized to reduce its surface energy and improve the stability, consistency and high precision of printing; finally, the glass substrate is dried and air-dried.

[0063] Step 2: Printing of the silver structure of the seed layer of the conformal antenna structure.

[0064] The pretreated cylindrical curved surface substrate is placed on the printing platform, and the seed layer silver structure (conductive layer) of the conformal antenna structure is printed on the cylindrical curved surface substrate using the curved surface conformal micro-nano 3D printing technology, with a printing line width of 6μm and an aspect ratio of 0.5:1. Printing process parameters: applied voltage 1200V, printing speed 10mm / s, applied air pressure 200kPa, printing height 120μm, and the printing nozzle is a glass-stainless steel coaxial nozzle with an inner diameter of 20μm. In the printing process, in-situ curing and sintering are performed simultaneously by laser, realizing printing-sintering synchronization.

[0065] Step 3: The printed conformal antenna structure seed layer is sintered and subjected to conductive treatment.

[0066] The conformal antenna structure seed layer substrate printed in step 2 is placed in a vacuum box for low-temperature sintering for conductivity treatment, followed by cleaning and nitrogen drying to completely remove dirt on the seed layer and substrate. The specific curing process is: curing and sintering at 160°C for 40 minutes. The purpose is to improve the conductivity of the seed layer on the one hand, and enhance the adhesion between the seed layer and the curved substrate on the other hand.

[0067] Step 4: Micro-electroforming of conformal antenna structure.

[0068] The conformal antenna structure seed layer printed in step 3 is subjected to an electroforming process, and the metal material nickel is further deposited on the seed layer silver. The deposition thickness is 5 microns. First, the components of the electroplating solution are weighed in proportion: 100g / L nickel sulfamate, 10g / L nickel chloride, 30g / L boric acid, 0.1g / L sodium dodecyl sulfate, the pH value of the electroforming solution is adjusted to 4, the solution temperature is set to 50°C, and the current density used is 1A / dm 2 , the electroforming time is 3 minutes, the solution circulation flow rate is 1.5 m / s, and then a conductive copper tape is attached to one side of the conductive metal grid structure and connected to the cathode of the precision micro-electroforming equipment. The metal nickel plate is connected to the anode and placed in the electroforming liquid, and the electroforming equipment is turned on to perform micro-electroforming of the metal nickel structure.

[0069] Step 5: Sample post-processing.

[0070] The electroformed samples were placed in an ultrasonic device for cleaning and ultrasonic treatment. The ultrasonic power was set to 400W to remove surface residues, and the samples were dried at a temperature of 85°C to finally obtain a composite structured curved conformal antenna.

[0071] Example 2

[0072] In this embodiment, nano-conductive silver paste is used as the printing material. First, a metal conformal antenna seed layer structure is printed on a curved substrate using a five-axis linkage electric field-driven jet deposition curved conformal micro-nano 3D printing technology based on an extraction electrode; the printed metal conformal antenna seed layer structure is then subjected to a low-temperature sintering and conductive treatment; subsequently, the metal conformal antenna seed layer structure after the conductive treatment is subjected to precise micro-electroforming, and metal nickel or silver is deposited on the silver surface of the metal conformal antenna seed layer; finally, the electroformed sample is cleaned and dried to complete the manufacture of the curved conformal antenna.

[0073] The specific process steps of the method for manufacturing a glass hemispherical conformal antenna based on composite micro-nano additive manufacturing in this embodiment are as follows:

[0074] Step 1: Pre-treat the substrate

[0075] Cleaning, hydrophobicity and drying of the hemispherical glass substrate. First, the surface of the hemispherical glass substrate is cleaned and decontaminated; then the glass surface is hydrophobicized to reduce its surface energy and improve the stability, consistency and high precision of printing; finally, the hemispherical glass substrate is dried and air-dried.

[0076] Step 2: Printing of the silver structure of the seed layer of the conformal antenna structure.

[0077] The pretreated hemispherical glass substrate was placed on the printing platform, and the conformal antenna structure seed layer silver structure was printed on the hemispherical glass substrate using the curved conformal micro-nano 3D printing technology, with a print line width of 15μm and an aspect ratio of 0.6:1. Printing process parameters: applied voltage 1000V, printing speed 8mm / s, applied air pressure 150kPa, printing height 140μm, and a stainless steel nozzle with an inner diameter of 30μm. In the printing process, in-situ curing and sintering were performed simultaneously by laser, achieving printing-sintering synchronization.

[0078] Step 3: The printed conformal antenna structure seed layer is sintered and subjected to conductive treatment.

[0079] The conformal antenna structure seed layer substrate printed in step 2 is placed in a vacuum box for sintering to conduction treatment, followed by cleaning and nitrogen drying to completely remove dirt on the seed layer and substrate. The specific sintering parameters are: 160°C curing and sintering for 40 minutes. The purpose is to improve the conductivity of the metal grid structure on the one hand, and enhance the adhesion of the metal grid structure to the curved substrate on the other.

[0080] Step 4: Micro-electroforming of conformal antenna structure.

[0081] The conformal antenna structure seed layer printed in step 3 is subjected to an electroforming process, and the metal material silver is further deposited on the seed layer silver. The deposition thickness is 6 microns.

[0082] Step 5: Sample post-processing.

[0083] The electroformed samples were placed in an ultrasonic device for cleaning and ultrasonic treatment. The ultrasonic power was set to 400W to remove surface residues, and the samples were dried at 90°C to obtain a hemispherical glass substrate curved conformal antenna.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a curved conformal antenna based on composite micro-nano additive manufacturing, characterized in that: The process steps include: Step 1: Substrate pretreatment: Perform hydrophobic treatment on the curved surface substrate, wherein the hydrophobic treatment includes decontamination and cleaning of the curved surface substrate, surface hydrophobicization and drying; Step 2: Printing of seed layer of conformal antenna structure: Use a five-axis linkage electric field driven jet deposition micro-nano 3D printer based on extraction electrodes to print the seed layer of conformal antenna structure on the curved substrate. During the printing process, laser or UV lamp is used for in-situ curing and sintering to achieve simultaneous printing and sintering. Combine different printing modes and change different printing process parameters to achieve printing of seed layers with different line widths and precisions. Line width is 0.5μm-200μm; Step 3: Conductive treatment of the printed conformal antenna structure seed layer: The conformal antenna structure seed layer substrate printed in step 2 is placed in a vacuum box for sintering to conduct the conductive treatment, and then cleaned and nitrogen-dried to completely remove the dirt on the seed layer and the substrate; Step 4: Micro-electroforming or chemical plating of conformal antenna structure: The conformal antenna structure seed layer printed in step 3 is subjected to electroforming or chemical plating process, and metal material is further deposited on the seed layer; Step 5: Sample post-processing: Clean the micro-electroformed or chemically plated samples to remove the residues produced during the deposition process, and then dry the samples to prepare a large-size, high-precision curved conformal antenna; The printing material used for the conformal antenna structure seed layer in step 2 includes high-viscosity nano silver paste, nano nickel / silver metal solution, and modified liquid metal; The thickness of the deposited metal material in step 4 is 3 microns to 20 microns; The printing device in step 2 is a five-axis linkage electric field driven jet deposition micro-nano 3D printer based on extraction electrodes, which can complete five-degree-of-freedom printing and realize the printing of conformal antenna patterns by adjusting the rotation angle of the rotating table; The conductive treatment process of the conformal antenna in step 2 is to place the conductive metal paste under a laser sintering machine at 150°C for simultaneous curing and sintering with printing according to the optimal curing process conditions of the conductive metal paste used, so as to prevent the printed material from diffusing on the substrate and improve the printing accuracy and efficiency; The micro-electroforming process in step 4 is as follows: firstly, the reagent materials required for the electroforming solution are weighed in a certain proportion, and then, they are fully dissolved in sequence to finally obtain the required electroforming solution, and the pH value of the solution is adjusted to be within the range of 3-4.5; In the chemical plating process of step 4, firstly, the reagent materials required for the chemical plating solution are weighed in a certain proportion, and then they are fully dissolved in sequence to finally obtain the required chemical plating solution, and the pH value of the solution is adjusted to be within the range of 3-4.5; In the micro-electroforming process in step 4, a conductive copper tape is attached to one side of the conductive layer of the conformal antenna and connected to the cathode of the precision micro-electroforming equipment, and a metal plate is connected to the anode and placed in the electroforming solution, waiting for the solution to undergo a chemical reaction to deposit a layer of metal on the surface of the conductive layer; The micro-electroforming material includes one or more of nickel, chromium, titanium and copper; In step 2, the distance and direction between the printing nozzle and the curved substrate remain the same, that is, the distance is always within the range allowed by the accuracy, and the direction is always vertically printed along the normal direction of the curved substrate; In the electroforming process in step 4, a constant temperature monitoring system and a solution circulation system are used to control the temperature of the electroforming solution in real time to ensure that the temperature of the electroforming solution is always within 45-55° C., and the solution circulation speed in the solution circulation system is 1-2 m / s; In the electroforming process in step 4, an ultrasonic vibrator is added to the electroforming solution.

2. The method according to claim 1, characterized in that: The curved surface substrate in step 1 is any one or more of a sphere, a hemisphere, a cylinder, a cone, a parabola, an arbitrary curved surface, and a 3D substrate obtained by cutting, molding, or 3D printing.

3. The method according to claim 1, characterized in that The printing path of the conformal antenna in step 2 can generate corresponding processing codes according to the shape of different curved substrates, and can be imported into the machine system to coordinately adjust different printing process parameters to complete the printing of conformal antennas with line widths in the range of 0.5-200 μm and different printing speeds in the range of 1-200 mm / s.

4. The method according to claim 1, characterized in that: The laser in step 2 is a fine-point laser with a spot diameter of less than 0.1 mm, which is beneficial to improving the curing effect.

5. The method according to claim 1, characterized in that The drying temperature range of the sample post-processing in step 5 is 80-90° C., and the cleaning agent is a reagent that does not chemically react with the sample.

6. The method according to claim 1, characterized in that The printing nozzle used in step 2 is a glass needle with an inner diameter ranging from 1 to 300 μm and treated with gold spraying and conductive treatment, a stainless steel nozzle or a Musashi needle.

7. The method according to claim 1, characterized in that The printing process parameter ranges in step 2 are: applied voltage of 100V-2000V, air pressure of 30-200kPa, printing speed of 1-100mm / s, and nozzle diameter of 1-300μm.

8. The method according to claim 1, characterized in that The laser and the nozzle in step 2 are fixed at the same time, and a certain distance and direction are designed so that the printing path remains completely consistent.

9. The method according to claim 1, characterized in that: The height of the micro-electroforming in step 4 can be adjusted according to the concentration of the metal solution and the electroforming time.

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