Method and system for manufacturing curved conformal multilayer circuits based on charge-controlled micro-nano 3D printing

Abstract

The present invention provides a method and system for charge-controlled electric field-driven jet micro-nano 3D printing of curved surface conformal multilayer circuits. This method utilizes charge injection electrowetting and contact electric field-driven jet micro-nano 3D printing to form high-precision conformal thin-film dielectric layers. This method combines active residual charge elimination with non-contact electric field-driven jet deposition micro-nano 3D printing to produce high-resolution curved surface conformal circuits. By organically combining active charge control with electric field-driven jet micro-nano 3D printing, high-precision conformal thin-film dielectric layers and conductive layers, as well as their interlayer interconnects, can be integrated to print conformal circuits. This method achieves efficient, low-cost, high-precision, and uniform production of curved surface conformal multilayer circuits.

Description

Technical Field

[0001] The present invention belongs to the field of electronic manufacturing and micro-nano 3D printing, and specifically relates to a method and system for printing curved surface conformal multilayer circuits based on charge-controlled electric field-driven jetting. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Conformal electronics is a cutting-edge new 3D structural electronics product that has emerged in recent years alongside advances in manufacturing technologies (particularly multi-material micro-nano 3D printing). This product overturns the traditional concept of separating mechanical structure and electronic circuitry (designed and manufactured separately, then assembled). By tightly integrating mechanical structure and electronic circuitry (fabricating conformal electronic circuits on 3D structures and complex curved surfaces, achieving organic integration of structure, functional circuitry, and electronics, and integrating structure and electronic functions), it not only facilitates product multifunctionality, miniaturization, lightweighting, and intelligence, but also provides a novel solution for the development of disruptive innovative products. Currently, conformal electronics has found widespread application in a wide range of fields, including aerospace, defense and military, biomedical, automotive, wearable devices, health monitoring, and smart structures. Typical applications of conformal electronics include conformal antennas, frequency selective surface (FSS) stealth radar radomes, structural electronics, 3D sensors, electronic skin, robotics, microsystem integration, and 3D packaging. Conformal electronics generally consist of a 3D substrate, dielectric layers, conductive layers, interlayer interconnects, and packaging layers.

[0004] Surface conformal electronics generally include a 3D substrate, a dielectric layer (dielectric layer), a conductive layer, an interlayer interconnection circuit, a packaging layer, etc. Currently, most surface conformal electronics directly pattern the conductive layer on the substrate surface, that is, pattern the conformal electronics and circuits on the substrate surface, and basically do not involve multi-layer dielectric layers, multi-layer conductive layers, and vertical interconnections between layers. This seriously limits the multifunctionality and high performance of surface conformal electronics. For example, the existing FSS faces problems such as poor conformality, low wave transmission efficiency, narrow-band response, and poor anti-interference ability. It cannot meet the problem of passing multi-band broadband electromagnetic waves. It is urgent to develop multi-layer frequency selective surfaces (FSS) and ultra-wideband FSS stealth radar cover technology based on multi-layer structures. Traditional single-layer conformal antennas have the problem of narrow bandwidth. It is urgent to develop multi-layer broadband conformal antennas to achieve multi-band communication. Therefore, many curved conformal electronic products and applications such as broadband and strong stealth FSS stealth radar radome, broadband omnidirectional conformal antenna, aircraft intelligent skin, curved multilayer printed circuit boards, smart wearable devices, 3D structural electronics, structural health monitoring, 3D sensors, intelligent structures, electromagnetic metamaterials, soft robots, etc. have a huge demand for 3D circuits and curved conformal multilayer circuits, especially the manufacturing of complex curved conformal multilayer circuits is the key core technology to realize these high-performance curved conformal electronic products.

[0005] At present, scholars at home and abroad have proposed a variety of curved surface conformal electronic circuit manufacturing technologies, mainly including: (1) conformal transfer technology; (2) LPKF-LDS laser direct forming of Germany's Lepco; (3) five-axis laser etching; (4) aerosol jet printing of the United States Optomec; (5) inkjet printing; (6) electrohydrodynamic jet printing; (7) vertical jet curved surface conformal micro 3D printing based on local polarization electric field drive; (8) curved surface lithography; (9) extrusion direct writing. In addition, there are multi-axis linkage machining, holographic lithography, etc. However, these existing technologies have difficulties in manufacturing complex curved surface conformal electronic circuits such as non-unfolded surfaces, variable curvature, and multiple curvatures; and the bonding strength between the conformal circuit and the substrate interface is poor, and the interlayer positioning accuracy is low. In addition, the existing curved conformal circuit manufacturing technology still finds it difficult to achieve high-precision dielectric film manufacturing, especially the high-precision ultra-thin film dielectric layer (high-precision 3D sensors, wearable devices, etc.) and ultra-thick dielectric layer (used for multi-layer FSS, conformal antennas, etc.) manufacturing, which currently cannot meet actual engineering needs.

[0006] In summary, the current manufacturing of curved surface conformal multilayer circuits mainly faces the following difficulties: (1) Existing manufacturing technologies cannot realize the manufacturing of high-precision, uniform and consistent curved surface dielectric layers (conformal films), resulting in the inability to realize the manufacturing of curved surface conformal multilayer circuits; (2) It is difficult or even impossible to realize the manufacturing of high-resolution, high-performance conformal circuits on non-expandable, multi-curvature and arbitrarily complex curved surface substrates; (3) Existing curved surface printing technologies face the problems of slippage and spreading of printed droplets (printing materials with low viscosity), poor printing uniformity and consistency, low precision, poor electrical performance, and poor interface bonding strength; (4) It is difficult to manufacture vertical interconnections of curved surface multilayer circuits. Therefore, existing technologies cannot realize the manufacturing of high-precision curved surface conformal multilayer circuits, especially the manufacturing of high-precision curved surface conformal multilayer circuits on non-expandable surfaces, multi-curvature surfaces, etc. Both academia and industry are in urgent need of developing new manufacturing technologies to realize the efficient, low-cost and high-consistency manufacturing of high-resolution, high-performance (high conductivity, high adhesion), high-precision curved surface conformal multilayer circuits on non-expandable, multi-curvature and arbitrarily complex curved surface substrates. Summary of the Invention

[0007] To address these issues, the present invention proposes a novel method for fabricating curved, conformal, multilayer circuits based on charge-controlled, electric-field-driven jet micro-nano 3D printing. This method combines charge injection electrowetting with electric-field-driven jet micro-nano 3D printing to form high-precision conformal thin-film dielectric layers. Furthermore, active residual charge elimination and contactless electric-field-driven jet deposition micro-nano 3D printing are combined to fabricate high-resolution curved, conformal circuits. By integrating active charge control with electric-field-driven jet micro-nano 3D printing, high-precision conformal thin films and conformal circuits can be simultaneously and integrated, achieving efficient and low-cost fabrication of high-precision, curved, conformal, multilayer circuits.

[0008] A method and system for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field-driven jet micro-nano 3D printing can achieve efficient and low-cost manufacturing of high-precision curved surface conformal multilayer circuits.

[0009] According to some embodiments, the present invention adopts the following technical solutions:

[0010] A method for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field-driven jet micro-nano 3D printing, comprising the following steps:

[0011] Step (1): pre-treating the substrate (a curved three-dimensional model formed by 3D printing, cutting, injection molding, etc.) by degreasing and cleaning the substrate and then fixing it on the printing platform;

[0012] Step (2): Print the dielectric layer. According to the design requirements, select a suitable dielectric material (polyimide PI, polytetrafluoroethylene PTFE, liquid crystal polymer LCP, resin, PDMS, etc.), and place the prepared printing material into the conformal thin film dielectric layer printing nozzle (using a conductive nozzle, the nozzle is connected to the positive pole of the high-voltage power supply). Use the charge injection electric field driven jet deposition micro-nano 3D printing process, combined with optimized process parameters (voltage, printing speed, back pressure, printing height, etc.) to print the first dielectric layer. Through active charge injection and charge injection electrowetting effect, combined with electric field driven jet deposition micro-nano 3D printing, high-precision curved surface conformal thin film dielectric layer manufacturing is achieved.

[0013] Step (3): Eliminate residual charge. Use a micro static eliminator to eliminate the residual charge on the printed dielectric layer and substrate.

[0014] Step (4): Print the conformal circuit of the conductive layer. Select a suitable conductive ink (nanosilver paste / silver ink, carbon paste, conductive polymer, etc.) and place it on the conformal circuit printing nozzle (using an insulating nozzle such as glass or ceramic, and the extraction electrode set on the outside of the nozzle is connected to the positive electrode of the high-voltage power supply). Use a non-contact electric field driven jet deposition micro-nano 3D printing process, combined with optimized process parameters (voltage, printing speed, back pressure, printing height, etc.) to print the first conductive layer conformal circuit. Using a non-contact electric field driven jet deposition micro-nano 3D printing process and a glass insulating nozzle, since there is no charge injection, crosstalk is reduced, printing stability is improved, and high-resolution, high-density curved surface conformal microcircuit manufacturing is achieved. And through curing, sintering and other processes, the printed circuit is made conductive.

[0015] Step (5): Printing the dielectric layer. Execute the operation of step (2) to print the second (or next) dielectric layer.

[0016] Step (6): Fabricating vertical interconnected vias. Use a laser printing module (to fabricate multiple vertically interconnected microvias on the second dielectric layer.

[0017] Step (7): Eliminate residual charge. Perform the operation of step (3).

[0018] Step (8): Print the conductive layer conformal circuit and fill the vertical interconnect vias. Perform the same steps as in step 4 to print the second conductive layer conformal circuit. Subsequently, print the circuit filling the vertical interconnect vias to complete the vertical interconnect circuit fabrication. Finally, through curing and sintering, the printed conformal circuit is made conductive.

[0019] Step (9): Repeat the operations of step (5), step (6), step (7), and step (8) to complete the manufacture of all curved conformal dielectric layers, conductive layer conformal circuits, and interlayer vertical interconnection circuits.

[0020] Step (10): Print the encapsulation layer.

[0021] Step (11): Post-processing.

[0022] As an optional embodiment, in step (1), the matrix material includes but is not limited to ceramic, PEEK, plastic, glass, resin, silicone, metal, etc., and the matrix shape includes but is not limited to any 3D curved surface geometry of developable surface and non-developable surface.

[0023] As an optional embodiment, in step (2), the dielectric material includes but is not limited to at least one of polyimide PI, polytetrafluoroethylene PTFE, liquid crystal polymer LCP, resin, PDMS, and ceramic; and the viscosity range is 1-50000 cps.

[0024] As an optional embodiment, in step (2), a charge injection electric field driven jet deposition micro-nano 3D printing process is used, and the conductive nozzle is directly connected to a high voltage power supply. Printing parameters include a printing voltage of -5000V to +5000V, a printing pressure of 0-500kPa, a printing speed of 0-80mm / s, and a printing height of 0.04-3mm.

[0025] As an optional embodiment, in step (4), the conductive material includes at least one of nanosilver ink / silver paste, conductive copper ink / copper paste, silver nanowire ink, carbon paste and conductive polymer, and has a viscosity ranging from 1 to 50,000 cps.

[0026] As an optional embodiment, in step (4), a non-contact electric field driven jet deposition micro-nano 3D printing process is used, using an insulating nozzle made of glass, ceramic, etc., and an extraction electrode disposed on the outside of the nozzle is connected to the positive electrode of a high-voltage power supply. Printing parameters include a printing voltage of -3000V to +3000V, a printing pressure of 0-300kPa, a printing speed of 0-50mm / s, and a printing height of 0.03-0.5mm.

[0027] As an optional embodiment, in step (8), a high-solid content stretchable conductive material is preferably used as the printing material. The high-solid content stretchable conductive material includes at least one of a stretchable silver paste, a stretchable carbon paste, and a conductive polymer, has a solid content greater than 60%, and a viscosity range of 0-50,000 cps. Printing parameters include a printing voltage of 0-2000 V, a printing pressure of 0-500 kPa, and a printing speed of 0-20 mm / s.

[0028] A charge-controlled electric field-driven jet micro-nano 3D printing curved surface conformal multi-layer circuit manufacturing system, including a five-axis linkage micro 3D printer, a laser drilling module, a control system, etc.

[0029] The five-axis linkage micro 3D printer includes a single potential contact electric field conductive nozzle (conformal thin film printing nozzle), a non-contact electric field nozzle (conformal circuit printing nozzle) and an electrostatic eliminator, wherein:

[0030] The single potential contact electric field conductive nozzle (conformal thin film dielectric printing nozzle) includes a barrel, an adapter and a printing nozzle, wherein the end of the barrel is provided with a printing conductive nozzle, the upper end of the barrel is provided with an adapter, and the barrel is connected to an air pressure module;

[0031] The non-contact electric field nozzle (conformal circuit printing nozzle) includes a barrel, an adapter, a printing nozzle and an annular electrode. The end of the barrel is provided with the printing nozzle, the outer cover of the printing nozzle is provided with the annular electrode, the upper end of the barrel is provided with an adapter, and the barrel is connected to the air pressure module;

[0032] The static eliminator and the single potential contact electric field conductive nozzle and the non-contact electric field nozzle are arranged side by side, or are automatically switched by using a special device.

[0033] As an optional embodiment, the optional range of the inner diameter of the print nozzle of the single potential contact electric field conductive nozzle is 0.1-0.6mm, the print nozzle material is conductive material, the print nozzle is externally connected to a high-voltage power supply, and the adjustable range of the high-voltage power supply is -5000V to +5000V.

[0034] As an optional embodiment, the print head of the non-contact electric field nozzle is made of non-conductive material, and the annular electrode is fixed on the outside of the print head and does not directly contact the printing material.

[0035] As an optional embodiment, the optional range of the inner diameter of the printing nozzle of the non-contact electric field nozzle is 0.1-0.6 mm, the annular electrode is connected to a high-voltage power supply, and the adjustable range of the high-voltage power supply is -5000V to +5000V.

[0036] As an optional implementation, the pressure range of the air pressure module is 0-500kPa.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The present invention solves the difficult problem of manufacturing high-resolution surface conformal multilayer circuits on arbitrarily complex surfaces (especially non-developable surfaces, multi-curvature, and arbitrarily complex surfaces).

[0039] The present invention can realize high-efficiency and low-cost manufacturing of high-precision curved surface conformal multi-layer circuits.

[0040] The present invention can realize high-precision manufacturing of curved surface conformal films, and solves the problem of conformal manufacturing of complex curved surface dielectric layers.

[0041] The manufacturing method of the present invention has the outstanding advantages of low cost, high precision and wide adaptability.

[0042] The present invention realizes the efficient, low-cost, high-precision and uniform manufacturing of curved conformal multilayer circuits, and in particular provides a new solution with industrial application prospects for many curved conformal electronic products and applications such as broadband strong stealth FSS stealth radar antenna covers, broadband omnidirectional conformal antennas, aircraft intelligent skins, curved multilayer printed circuit boards, smart wearable devices, 3D structural electronics, structural health monitoring, 3D sensors, smart structures, electromagnetic metamaterials, soft robots, etc.

[0043] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary 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.

[0045] Figure 1 This is a schematic diagram of the method for manufacturing curved conformal multilayer circuits based on charge-controlled electric field-driven jet micro-nano 3D printing of the present invention.

[0046] Figure 2 This is a schematic diagram of the charge injection electrowetting effect principle of the present invention.

[0047] Figure 3 This is a schematic diagram of the principle of micro-nano 3D printing based on non-contact electric field driving of the present invention.

[0048] Figure 4 This is a schematic diagram of the conductive nozzle structure for printing a conformal thin film dielectric layer according to the present invention.

[0049] Figure 5 This is a schematic diagram of the conformal circuit printing nozzle structure of the present invention.

[0050] Figure 6 This is a process flow chart for manufacturing curved conformal multilayer circuits using charge-controlled electric field-driven jet micro-nano 3D printing.

[0051] Among them, 1. Air pressure module, 2. Adapter, 3. Storage barrel, 4. Print head, 5. Ring electrode. DETAILED DESCRIPTION

[0052] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0053] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0054] 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 invention. As used herein, unless the context clearly indicates otherwise, the singular form is 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, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0055] In the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0056] Example 1

[0057] A method for manufacturing curved conformal multilayer circuits based on charge injection electrowetting and electric field driven micro-nano 3D printing, such as Figure 1 As shown, it mainly includes the following steps:

[0058] (1) Pretreatment of the substrate: First, the substrate (a curved three-dimensional model formed by 3D printing, cutting, injection molding, etc.) is degreased and cleaned; then, a processing code is generated according to the required circuit pattern and input into a five-axis linkage micro-nano 3D printer.

[0059] (2) Printing the first dielectric layer: According to the design requirements, select suitable dielectric materials (polyimide PI, polytetrafluoroethylene PTFE, liquid crystal polymer LCP, resin, PDMS, etc.), and place the prepared dielectric material into the conformal thin film dielectric layer printing nozzle (using a conductive nozzle, the nozzle is connected to the positive pole of the high-voltage power supply), use the charge injection electric field driven jet deposition micro-nano 3D printing process, combined with optimized process parameters (voltage, printing speed, back pressure, printing height, etc.), print the first dielectric layer. Through active charge injection and charge injection electrowetting effect, combined with electric field driven jet deposition micro 3D printing, high-precision curved surface conformal thin film dielectric layer manufacturing is achieved, and the dielectric layer is cured by heating, UV and other curing methods.

[0060] (3) Elimination of residual charge: The static eliminator device on the five-axis linkage micro 3D printer is used to eliminate the residual charge of the printed dielectric layer and substrate.

[0061] (4) Printing (first layer) conductive layer conformal circuit: Select a suitable conductive ink (nanosilver paste / silver ink, carbon paste, conductive polymer, etc.) and place it on the conformal circuit printing nozzle (using an insulating nozzle such as glass or ceramic, with the extraction electrode set on the outside of the nozzle connected to the positive electrode of the high-voltage power supply). Use a non-contact electric field driven jet deposition micro-nano 3D printing process, combined with optimized process parameters (voltage, printing speed, back pressure, printing height, etc.) to print the first conductive layer conformal circuit. Using a non-contact electric field driven jet deposition micro-nano 3D printing process and a glass insulating nozzle, since there is no charge injection, crosstalk is reduced, printing stability is improved, and high-resolution, high-density curved surface conformal microcircuit manufacturing is achieved. And through curing, sintering and other processes, the printed conformal circuit is made conductive.

[0062] (5) Print the second (or next) dielectric layer and repeat the steps in step (2).

[0063] (6) Fabrication of vertical interconnected vias: A laser printing module is used to fabricate multiple vertically interconnected microvias on the second dielectric layer.

[0064] (7) Eliminate residual charge. Perform the operation in step 3.

[0065] (8) Printing the conductive layer circuit and filling the vertical interconnect vias. Perform the operation in step 4 to print the second conductive layer circuit. Subsequently, print the circuit filling the vertical interconnect vias to complete the fabrication of the vertical interconnect circuit. Finally, through curing, sintering, and other processes, the printed circuit is made conductive.

[0066] (9) Repeat the operations (5) to (8) to complete the fabrication of all curved conformal dielectric layers and conductive layer conformal circuits.

[0067] (10) Printing the packaging layer: Use the packaging material as the printing material to encapsulate the circuit.

[0068] (11) Post-processing: Related electronic components, feed connectors, etc. can be connected as needed, and post-curing, sintering and other treatments can be performed.

[0069] In some embodiments, the matrix material of step (1) includes but is not limited to ceramics, PEEK, plastic, glass, resin, silicone, metal, etc., and the matrix shape includes but is not limited to any 3D curved surface geometry of developable surface and non-developable surface.

[0070] In some embodiments, the dielectric material in step (2) includes but is not limited to polyimide (PI), resin, ceramic, polydimethylsiloxane (PDMS), etc.; and the viscosity range is 1-50000 cps.

[0071] In some embodiments, the printing parameters in step (2) include a printing voltage of -5000V to +5000V, a printing pressure of 0-500kPa, a printing speed of 0-80mm / s, and a printing height of 0.04-3mm.

[0072] In some embodiments, the conductive material in step (4) includes nanosilver ink / silver paste, conductive copper ink / copper paste, silver nanowire ink, carbon paste, and conductive polymer, and has a viscosity ranging from 1 to 50,000 cps;

[0073] In some embodiments, the printing parameters in step (4) include a printing voltage of -3000V to +3000V, a printing pressure of 0-300kPa, a printing speed of 0-50mm / s, and a printing height of 0.03-0.3mm.

[0074] In some embodiments, the curing methods in steps (2), (4), (5), and (8) include but are not limited to heating curing, ultraviolet curing, infrared curing, and chemical curing.

[0075] Example 2

[0076] A method for manufacturing a conformal multilayer frequency selective surface device based on charge injection electrowetting and electric field driven micro 3D printing, such as Figure 6 shown.

[0077] This embodiment uses a hemispherical Teflon (PTFE) substrate with a radius of 10 cm, a printed circuit structure of a multi-layer frequency selective surface, a dielectric material of polyimide (PI), and a conductive material of nano-silver paste. The specific implementation steps are as follows:

[0078] Step 1: Pre-treat the substrate. First, clean the Teflon substrate to remove surface impurities. Then, use a scanner to digitally reverse engineer the printed substrate, establish a processing model, and generate processing code based on the desired circuit pattern. This code is then input into the five-axis micro-nano 3D printer.

[0079] Step 2: Print the first PI dielectric layer, using PI solution as the printing material, and place the prepared printing material into the conformal film printing nozzle (using a stainless steel conductive nozzle, the nozzle is connected to the positive pole of the high-voltage power supply), and use the charge injection electric field to drive the jet deposition micro-nano 3D printing process, such as Figure 4 Move the print head to the printing starting point of the substrate, connect the single potential print head to the positive electrode of the high voltage power supply, set the printing parameters (print head inner diameter 0.1mm, printing height 0.1mm, printing voltage 2000V, printing pressure 100kPa, workbench moving speed 20mm / s), load the printing path, and under the action of the charge injection electrowetting effect, conformally print the first dielectric layer PI film on the surface of the Teflon substrate, as shown. Figure 2The dielectric layer is cured by heating.

[0080] Step 3: Eliminate residual charge: Use the static eliminator on the five-axis linkage micro-nano 3D printer to eliminate the residual charge in the printed dielectric layer and substrate.

[0081] Step 4: Print the first conformal circuit layer: Use nano-conductive silver paste as the printing material and place it on the conformal circuit printing nozzle (a glass nozzle is used, and the extraction electrode set on the outside of the nozzle is connected to the positive electrode of the high-voltage power supply). Use a non-contact electric field driven jet deposition micro-nano 3D printing process, such as Figure 5 Move the print head to the circuit printing starting point, set the printing parameters (nozzle inner diameter 0.05mm, printing height 0.08mm, printing voltage 2000V, printing air pressure 200kPa, workbench moving speed 40mm / s), load the printing path, and use the self-excited electrostatic field effect to make the conductive material form a Taylor cone to achieve conformal printing of high-precision circuits, as shown. Figure 3 As shown in the figure, the absence of charge injection reduces crosstalk, improves printing stability, and enables the fabrication of high-resolution, high-density, curved surface conformal microcircuits. Furthermore, through heat curing and sintering, the printed wires become conductive.

[0082] Step 5: Since there is no interlayer interconnection in this embodiment, there is no need to print interlayer vertical interconnection circuits. Simply repeat steps (2)-(4) to complete the fabrication of conformal circuits for all dielectric and conductive layers.

[0083] Step 6: Printing the encapsulation layer and post-processing: After printing is complete, the multi-layer frequency selective surface device is sprayed with an anti-oxidation coating.

[0084] In other embodiments, the substrate material in step 1 includes but is not limited to ceramic, PEEK, plastic, glass, resin, silicone, metal, etc., and the substrate shape includes but is not limited to any 3D curved surface geometry of a developable surface and a non-developable surface;

[0085] In other embodiments, the dielectric material in step 2 is not limited to one of ceramic and polydimethylsiloxane (PDMS);

[0086] In other embodiments, the printing parameters in step 2 include a printing voltage of -5000V to +5000V, a printing pressure of 0-500kPa, a printing speed of 0-80mm / s, and a printing height of 0.04-3mm.

[0087] In other embodiments, the conductive material in step 4 includes nanosilver ink, conductive copper ink / copper paste, silver nanowire ink, carbon paste, or conductive polymer, and has a viscosity ranging from 0 to 10,000 cps;

[0088] In other embodiments, the printing parameters in step 4 include a printing voltage of -3000V to +3000V, a printing pressure of 0-300kPa, a printing speed of 0-50mm / s, and a printing height of 0.03-0.3mm.

[0089] Example 3

[0090] A method for manufacturing curved conformal multilayer circuits based on charge injection electrowetting and electric field-driven micro-nano 3D printing is described. In this embodiment, a non-developable curved ceramic substrate with an area of ​​20×20 cm is used. The printed circuit structure is a multilayer interconnected circuit. PDMS is used as the dielectric material, and nanosilver paste and stretched silver paste are used as the conductive materials. The specific implementation steps are as follows:

[0091] Step 1: Pre-treat the substrate. First, clean the ceramic substrate to remove surface impurities. Then, use a scanner to digitally reverse engineer the printed substrate, establish a machining model, and generate machining code based on the desired circuit pattern. This code is then input into the five-axis micro-nano 3D printer.

[0092] Step 2: Print the first PDMS dielectric layer. Use PDMS precursor solution as the printing material, and place the prepared printing material into the conformal thin film dielectric printing nozzle (using a stainless steel conductive nozzle, the nozzle is connected to the positive electrode of the high-voltage power supply), and use the charge injection electric field to drive the jet deposition micro-nano 3D printing process, such as Figure 4 Move the print head to the printing starting point of the substrate, connect the single potential print head to the positive electrode of the high voltage power supply, set the printing parameters (print head inner diameter 0.2mm, printing height 0.2mm, printing voltage 3000V, printing pressure 200kPa, workbench moving speed 20mm / s), load the printing path, and under the action of the charge injection electrowetting effect, conformally print a layer of PDMS dielectric film on the surface of the ceramic substrate, as shown in Figure 1. Figure 2 The dielectric layer is cured by heating.

[0093] Step 3: Eliminate residual charge: Use the static eliminator device of the five-axis linkage micro-nano 3D printer to eliminate the residual charge in the dielectric layer and the substrate.

[0094] Step 4: Print the conformal circuit of the first conductive layer: Use conductive silver paste as the printing material and place it on the conformal circuit printing nozzle (a glass nozzle is used, and the extraction electrode set on the outside of the nozzle is connected to the positive electrode of the high-voltage power supply), and use a non-contact electric field driven jet deposition micro-nano 3D printing process, such as Figure 5Move the print head to the circuit printing starting point, set the printing parameters (nozzle inner diameter 0.08mm, printing height 0.15mm, printing voltage -2000V, printing pressure 150kPa, workbench moving speed 40mm / s), load the printing path, and use the self-excited electrostatic field effect to make the conductive material form a Taylor cone to achieve conformal printing of high-precision circuits, as shown. Figure 3 As shown in the figure, the absence of charge injection reduces crosstalk, improves printing stability, and enables the fabrication of high-resolution, high-density, curved, conformal microcircuits. After printing, the conductors are cured by heating.

[0095] Step 5: Print the second PDMS dielectric layer. Repeat the steps in step 2 to print the second (or next) dielectric layer.

[0096] Step 6: Fabricating vertical interconnection vias: A plurality of vertical interconnection vias are fabricated on the second dielectric layer using a laser printing module.

[0097] Step 7: Eliminate residual charge. Perform the operation in step 3.

[0098] Step 8: Print the second conductive layer conformal circuit and fill the vertical interconnect vias. Repeat Step 4 to print the second conductive layer circuit. Next, print the circuit filling the vertical interconnect vias, completing the vertical interconnect circuit. Finally, heat-curing the silver paste completes the printed circuit's conductivity.

[0099] Step 9: Repeat the operations of step 5, step 6, step 7, and step 8 to complete the fabrication of all curved conformal dielectric layers, conductive layer conformal circuits, and vertical interconnect circuits.

[0100] Step 10: Print the packaging layer. Encapsulate the curved conformal multilayer circuit.

[0101] Step 11: Post-processing: Perform dust and oxidation prevention on the multi-layer circuit.

[0102] In other embodiments, the curved surface substrate material in step 1 includes but is not limited to ceramic, PEEK, plastic, glass, resin, silicone, metal, etc., and the substrate shape includes but is not limited to any 3D curved surface geometry of a developable surface and a non-developable surface;

[0103] In other embodiments, the dielectric material in step 2 includes but is not limited to ceramics, polyimide (PI), etc.

[0104] In other embodiments, the printing parameters in step 2 include a printing voltage of -5000V to +5000V, a printing pressure of 0-500kPa, a printing speed of 0-80mm / s, and a printing height of 0.04-3mm.

[0105] In other embodiments, the conductive material in step 4 includes nanosilver ink, conductive copper ink / copper paste, silver nanowire ink, carbon paste, conductive polymer, stretched carbon paste / conductive polymer, etc., with a viscosity ranging from 0 to 10,000 cps;

[0106] In other embodiments, the printing parameters in step 4 include a printing voltage of -3000V to +3000V, a printing pressure of 0-300kPa, a printing speed of 0-50mm / s, and a printing height of 0.03-0.3mm.

[0107] Example 4

[0108] A curved conformal multilayer circuit manufacturing system includes a five-axis linkage micro-nano 3D printer, wherein the five-axis linkage micro-nano 3D printer includes a single-contact electric field conductive nozzle, a non-contact electric field nozzle, and an electrostatic eliminator, wherein:

[0109] like Figure 4 As shown, the conformal film printing nozzle includes a barrel 3, an adapter 2 and a single potential nozzle 4. The end of the barrel 3 is provided with a conformal film printing nozzle (a conductive nozzle is used, and the nozzle is connected to the positive electrode of the high-voltage power supply). The adapter 2 is provided at the upper end of the barrel 3, and the barrel 3 is connected to the air pressure module 1;

[0110] like Figure 5 As shown, the conformal circuit print head (non-contact electric field driven jet 3D print head) includes a barrel 3, an adapter 2, an insulating print head 4 and a ring electrode 5. The end of the barrel 3 is provided with an insulating print head (made of glass, ceramic, etc.), and the insulating print head jacket is provided with the ring electrode (connected to the positive electrode of the high-voltage power supply). The upper end of the barrel 3 is provided with an adapter 2, and the barrel 3 is connected to the air pressure module 1;

[0111] The conformal film printing nozzle, the conformal circuit printing nozzle, the static eliminator and the laser printing module are arranged side by side.

[0112] The inner diameter of the conformal thin film print head can be selected in the range of 0.1-0.6 mm. The print head material is a conductive material. The print head is externally connected to a high-voltage power supply, and the high-voltage power supply can be adjusted in the range of -5000V to +5000V.

[0113] The print head portion of the conformal circuit print head is made of non-conductive material, and the annular electrode 5 is fixed outside the print head 4 and does not directly contact the printing material.

[0114] As an optional embodiment, the inner diameter of the conformal circuit print head can be selected in the range of 0.1-0.6 mm, the annular electrode is connected to a high voltage power supply, and the high voltage power supply can be adjusted in the range of -5000V to +5000V.

[0115] As an optional embodiment, the pressure range of the air pressure module is 0-500kPa.

[0116] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made by those skilled in the art that fall within the spirit and principles of the present invention and do not require creative effort are intended to be within the scope of protection of the present invention.

Claims

1. A method for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field-driven jet micro-nano 3D printing, characterized in that: The following steps are involved: Step (1): pre-treating the substrate, degreasing and cleaning the substrate, and then fixing it on the printing platform; Step (2): Print the dielectric layer. According to the design requirements, select the appropriate dielectric material and place the prepared printing material into the conformal thin film dielectric layer printing nozzle. Use the charge injection electric field driven jet deposition micro-nano 3D printing process, combined with optimized process parameters, to print the first dielectric layer. Through active charge injection and charge injection electrowetting effect, combined with electric field driven jet deposition micro-nano 3D printing, high-precision curved surface conformal thin film dielectric layer manufacturing is achieved; Step (3): Eliminate residual charges on the printed dielectric layer and substrate; Step (4): Printing the conductive layer conformal circuit, selecting a suitable conductive ink and placing it on the conformal circuit printing nozzle, using a non-contact electric field driven jet deposition micro-nano 3D printing process, combined with optimized process parameters, printing the first conductive layer conformal circuit, and achieving conductivity of the printed circuit through curing and sintering treatment; Step (5): Printing the dielectric layer, performing the operation of step (2) to print the second or next dielectric layer; Step (6): manufacturing vertical interconnected vias, using a laser printing module to manufacture a plurality of vertically interconnected micro-holes on the second dielectric layer; Step (7): Eliminate residual charge; Step (8): Printing the conductive layer conformal circuit and filling the vertical interconnection through-holes, performing the operation of step (4), printing the second conductive layer conformal circuit, and then printing the circuit filling the vertical interconnection through-holes to complete the manufacture of the vertical interconnection circuit, and completing the printed conformal circuit conductivity through curing and sintering treatment; Step (9): Repeat the operations of step (5) to step (8) to complete the fabrication of all curved conformal dielectric layers and conductive layer conformal circuits and interlayer vertical interconnection circuits; Step (10): Printing the encapsulation layer; Step (11): Perform post-processing.

2. The method for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field driven jet micro-nano 3D printing according to claim 1, characterized in that: In the step (1), the material of the substrate includes one of ceramic, PEEK, plastic, glass, resin, silicone and metal, and the shape of the substrate includes any 3D curved surface geometry of a developable surface or a non-developable surface.

3. The method for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field driven jet micro-nano 3D printing according to claim 1, characterized in that: In the step (2), the dielectric material includes at least one of polyimide PI, polytetrafluoroethylene PTFE, liquid crystal polymer LCP, resin, PDMS and ceramic; and the viscosity range is 1-50000 cps.

4. The method for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field driven jet micro-nano 3D printing according to claim 1, characterized in that: In the step (2), a charge injection electric field is used to drive the jet deposition micro-nano 3D printing process, and the conductive nozzle is directly connected to the high voltage power supply; The optimized process parameters include printing voltage -5000V~+5000V, printing pressure 0-500kPa, printing speed 0-80mm / s, and printing height 0.04-3mm.

5. The method for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field driven jet micro-nano 3D printing according to claim 1, characterized in that: In the step (4), the conductive material includes at least one of nanosilver ink / silver paste, conductive copper ink / copper paste, silver nanowire ink, carbon paste and conductive polymer, and has a viscosity in the range of 1-50000 cps.

6. The method for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field driven jet micro-nano 3D printing according to claim 1, characterized in that: In the step (4), a non-contact electric field driven jet deposition micro-nano 3D printing process is used, a glass or ceramic insulating nozzle is used, and an extraction electrode provided on the outside of the nozzle is connected to the positive electrode of the high voltage power supply; The optimized process parameters include printing voltage -3000V~+3000V, printing pressure 0-300kPa, printing speed 0-50mm / s, and printing height 0.03-0.5mm.

7. The method for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field driven jet micro-nano 3D printing according to claim 1, characterized in that: In the step (8), a high-solid content stretchable conductive material is selected as the printing material, wherein the high-solid content stretchable conductive material includes at least one of a stretchable silver paste, a stretchable carbon paste, and a conductive polymer, has a solid content greater than 60%, and a viscosity range of 0-50000 cps; Printing parameters include printing voltage 0-2000V, printing air pressure 0-500kPa, and printing speed 0-20mm / s.

8. A system for manufacturing curved conformal multilayer circuits based on charge-controlled electric field-driven jet micro-nano 3D printing, characterized by: It includes a five-axis linkage micro 3D printer, a laser drilling module and a control system, including: The five-axis linkage micro 3D printer includes a single potential contact electric field conductive nozzle, a non-contact electric field nozzle and an electrostatic eliminator, wherein: The single potential contact electric field conductive nozzle includes a barrel, an adapter and a printing nozzle. The end of the barrel is provided with a printing conductive nozzle, the upper end of the barrel is provided with an adapter, and the barrel is connected to the air pressure module; The non-contact electric field nozzle includes a barrel, an adapter, a print nozzle and an annular electrode. The end of the barrel is provided with the print nozzle, the outer cover of the print nozzle is provided with the annular electrode, the upper end of the barrel is provided with an adapter, and the barrel is connected to the air pressure module; The static eliminator and the single potential contact electric field conductive nozzle and the non-contact electric field nozzle are arranged side by side, or are automatically switched by an automatic switching device.

9. The charge-controlled electric field driven jet micro-nano 3D printing curved surface conformal multilayer circuit manufacturing system according to claim 8, characterized in that: The optional range of the inner diameter of the print nozzle of the single potential contact electric field conductive nozzle is 0.1-0.6mm. The print nozzle material is conductive material. The print nozzle is externally connected to a high-voltage power supply, and the adjustable range of the high-voltage power supply is -5000V to +5000V.

10. The system for manufacturing curved surface conformal multilayer circuits based on charge-controlled electric field driven jet micro-nano 3D printing as claimed in claim 8, characterized in that: The print head of the non-contact electric field print head is made of non-conductive material, and the annular electrode is fixed on the outside of the print head and does not directly contact the printing material; The optional range of the inner diameter of the printing nozzle of the non-contact electric field nozzle is 0.1-0.6mm, and the annular electrode is connected to a high-voltage power supply, and the adjustable range of the high-voltage power supply is -5000V to +5000V; The pressure range of the air pressure module is 0-500kPa.

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