Miniaturized multi-electrode showerhead structure and control method

Abstract

The application provides a miniaturized multi-electrode nozzle structure and a control method, and relates to the technical field of electrohydrodynamic printing. By introducing a multi-electrode printing electrode group composed of a focusing electrode, an accelerating electrode and a deflection electrode, independent and fine regulation and control of ink droplet formation, acceleration and deflection are realized. The focusing electrode applies a constant voltage, which can promote the stable formation of a Taylor cone of ink at the nozzle outlet, overcoming the problem of unstable Taylor cone formation caused by uneven electric field distribution of the existing single-electrode nozzle. The accelerating electrode applies a preset pulsed electric field, which can stretch the liquid at the tip of the Taylor cone into a jet and break it into sub-micron droplets, while providing kinetic energy to the droplets, realizing sub-micron printing resolution. The deflection electrode applies a transverse electrostatic field, which can independently change the jetting direction of the droplets, solving the problem that the existing single-electrode nozzle has a single electric field control means and cannot independently regulate the droplet deposition trajectory, resulting in unstable droplet flight trajectory and large positioning error.

Description

Technical Field

[0001] This application relates to the field of electrohydrodynamic printing technology, and more specifically, to a miniaturized multi-electrode printhead structure and control method. Background Technology

[0002] Electrohydrodynamic printing, as an emerging micro-nano manufacturing process, forms a Taylor cone at the nozzle tip by applying a high-voltage electric field and ejects droplets at the micron or even nanoscale, showing great potential in fields such as printed electronics, biochips, and microelectromechanical systems.

[0003] Currently, the most common electrohydraulic printer nozzle structure consists of a single metal nozzle paired with an external flat electrode. This structure relies on a single electric field between the nozzle and the receiver, and while simple, it suffers from several inherent drawbacks. First, its printing resolution is severely limited. The droplet size is difficult to overcome the physical limitations of the nozzle diameter, typically not less than 10 micrometers. Even with optimization of the nozzle cone angle, the smallest droplet size achievable with current technology remains around 5 micrometers, making sub-micrometer printing difficult and failing to meet the extreme precision requirements of applications such as high-density integrated circuits.

[0004] Secondly, the electric field control methods are limited. Traditional structures cannot independently and precisely control the generation, acceleration, and deposition trajectory of droplets. This results in unstable flight trajectories of the ejected droplets, with positioning errors on the substrate typically exceeding 5 micrometers, making it difficult to achieve precise patterning in high-density transistor arrays or precision interdigitated electrodes.

[0005] Existing single-electrode nozzles suffer from uneven electric field distribution, resulting in excessively high field strength at the nozzle tip and excessively rapid attenuation at the periphery. Figure 5 As shown, this is the fundamental reason why droplet size is difficult to reduce and flight trajectory is difficult to control. Therefore, there is an urgent need in this field for a new structure of miniaturized electrofluid printhead that can achieve submicron-level printing resolution while ensuring high-precision positioning and stability.

[0006] There is currently no effective technical solution to the above problems. Summary of the Invention

[0007] The purpose of this application is to provide a miniaturized multi-electrode printhead structure and control method, which aims to solve the significant shortcomings of single-electrode printheads in existing electrohydrodynamic printing technology in terms of printing resolution and droplet trajectory control, and to meet the needs of high-precision, submicron-level printing.

[0008] In a first aspect, this application provides a miniaturized multi-electrode printhead structure, including: a printhead body, a printing electrode assembly, and a controller;

[0009] The nozzle body consists of a nozzle and an insulating substrate;

[0010] The printing electrode assembly includes a focusing electrode, an accelerating electrode, and a deflecting electrode arranged coaxially from top to bottom; an insulating substrate is located between the focusing electrode and the accelerating electrode, and the insulating substrate is connected to the printhead through the accelerating electrode and the deflecting electrode;

[0011] The focusing electrode, accelerating electrode, and deflecting electrode each have an inner cavity, which are connected to each other and used to transport ink. The nozzle of the printhead body is located at the tail end of the deflecting electrode, and the nozzle is connected to the inner cavity of the deflecting electrode. The nozzle is used to eject droplets of ink.

[0012] The controller is connected to the focusing electrode, the accelerating electrode, and the deflecting electrode. The focusing electrode is used to apply a constant voltage to cause the ink to form a Taylor cone at the exit of the printhead. The accelerating electrode is used to apply a preset pulsed electric field to stretch the liquid at the tip of the Taylor cone into a jet and break it into submicron droplets. The accelerating electrode is also used to provide kinetic energy to the droplets. The deflecting electrode is used to apply a transverse electrostatic field to change the jet direction of the droplets.

[0013] Through this technical solution, this application achieves independent and precise control of ink droplet formation, acceleration, and deflection by multi-electrode collaborative control, effectively solving the shortcomings of existing single-electrode printheads in terms of printing resolution and droplet trajectory control, and enabling sub-micron level printing and high-precision positioning.

[0014] Optionally, the deflection electrode includes a deflection electrode insulator whose width gradually decreases from top to bottom. A central groove is provided at the lower part of the deflection electrode insulator for detachably mounting the nozzle. A deflection electrode array is provided on the surfaces on both sides of the central groove. The deflection electrode array includes a left electrode and a right electrode that are insulated from each other. The width of both the left and right electrodes gradually decreases from top to bottom. The deflection electrode insulator is provided with two deflection electrode leads. The left and right electrodes are connected to the controller through the two deflection electrode leads respectively. The controller is used to independently apply deflection voltage to the left and right electrodes.

[0015] This technical solution allows for easy maintenance and replacement of the detachable printhead, while the independent left and right deflection electrodes enable more precise droplet trajectory control, further improving printing accuracy and flexibility.

[0016] Optionally, the inner diameter of the nozzle is 3μm-20μm.

[0017] This technical solution limits the nozzle inner diameter to a specific range, which helps optimize the formation of the Taylor cone and the size of the droplets, thereby achieving more stable submicron-level droplet jetting.

[0018] Optionally, the accelerating electrode has a cylindrical structure, and a dielectric layer is provided on the inner surface of the accelerating electrode. The dielectric layer is used to insulate and isolate it from the deflection electrode. The accelerating electrode is provided with a pulse signal input lead, which is used to connect to the controller.

[0019] This technical solution, using a cylindrical accelerating electrode structure in conjunction with a dielectric layer, effectively isolates the accelerating electrode from the deflecting electrode, ensuring electric field independence and thus improving the stability of droplet acceleration and deflection control.

[0020] Optionally, the dielectric layer is an alumina composite insulating layer or a hafnium dioxide composite insulating layer, and the dielectric layer thickness is 195nm-205nm.

[0021] Optionally, the focusing electrode is provided with a mounting hole, a control signal interface, and an ink inlet. The ink inlet connects to the inner cavities of the focusing electrode, the accelerating electrode, and the deflecting electrode. The control signal interface is connected to the controller, and the mounting hole is used to connect to the motion device of the printing equipment.

[0022] Optionally, the nozzle includes a glass guide tube and a glass nozzle connected in sequence, the glass guide tube being used to connect to the inner cavity of the deflection electrode.

[0023] Alternatively, the deflection electrode may be made of gold or molybdenum.

[0024] Alternatively, the accelerating electrode may be made of gold or molybdenum.

[0025] Secondly, this application also provides a control method for a miniaturized multi-electrode nozzle structure. Based on a miniaturized multi-electrode nozzle structure as described in any of the preceding claims, the control method for the miniaturized multi-electrode nozzle structure includes the following steps:

[0026] First, a constant voltage is applied to the focusing electrode via a controller to cause the ink to form a Taylor cone at the exit of the printhead;

[0027] Then, a pulse signal is applied to the acceleration electrode by the controller, which stretches the liquid at the tip of the Taylor cone at the nozzle outlet into a jet and breaks it into submicron droplets, and accelerates the droplets.

[0028] Finally, a dynamically changing voltage is applied to the deflection electrode via a controller to alter the direction of droplet ejection.

[0029] This technical solution achieves precise control of droplet generation, acceleration, and trajectory by independently controlling the focusing, acceleration, and deflection processes in stages. It effectively solves the problem of the single droplet control method in the existing technology, thereby improving printing accuracy and stability.

[0030] As can be seen from the above, the miniaturized multi-electrode printhead structure and control method provided in this application achieve independent and precise control over ink droplet formation, acceleration, and deflection by introducing a multi-electrode printing electrode group composed of a focusing electrode, an accelerating electrode, and a deflecting electrode. Applying a constant voltage to the focusing electrode enables the ink to stably form a Taylor cone at the printhead exit, overcoming the problem of unstable Taylor cone formation caused by uneven electric field distribution in existing single-electrode printheads. A stepped electric field distribution can be formed in the space below the printhead, thereby optimizing the electric field distribution and avoiding the problem of excessively high field strength at the tip and rapid attenuation at the periphery in traditional single-electrode printheads. This allows the droplet size to break through the limitations of traditional nozzle diameters, achieving sub-micron level printing. Simultaneously, the independent control capability of the multi-electrode allows for independent and precise control of droplet generation, acceleration, and deposition trajectory, significantly improving the stability of the droplet flight trajectory and greatly reducing positioning errors on the substrate, thus enabling precise patterning in applications such as high-density integrated circuits.

[0031] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing embodiments of this application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the miniaturized multi-electrode nozzle structure provided in an embodiment of this application.

[0033] Figure 2 An exploded view of the miniaturized multi-electrode nozzle structure provided in the embodiments of this application.

[0034] Figure 3 This is a cross-sectional view of a miniaturized multi-electrode nozzle structure provided in an embodiment of this application.

[0035] Figure 4 This is a schematic diagram of the electric field of the miniaturized multi-electrode nozzle structure provided in the embodiments of this application.

[0036] Figure 5 This is a schematic diagram of the electric field of a conventional single-electrode nozzle.

[0037] Labeling Explanation: 110, Printhead; 111, Glass Guide Tube; 112, Glass Nozzle; 120, Insulating Substrate; 210, Deflection Electrode; 214, Central Groove; 215, Deflection Electrode Lead; 211, Left Electrode; 212, Deflection Electrode Insulator; 213, Right Electrode; 220, Accelerating Electrode; 222, Dielectric Layer; 223, Pulse Signal Input Lead; 231, Mounting Hole; 230, Focusing Electrode; 232, Control Signal Interface; 233, Ink Inlet; 234, Inner Cavity. Detailed Implementation

[0038] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0039] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0040] Please refer to Figure 1-4 , Figure 1 This is a schematic diagram of a miniaturized multi-electrode nozzle structure in some embodiments of this application. It aims to solve the technical problems of existing electrohydrodynamic printing technologies, such as limited printing resolution, difficulty in exceeding nozzle diameter limits in droplet size, limited electric field control methods, and unstable droplet flight trajectories, inherent in single-metal nozzles coupled with external flat plates as electrode structures.

[0041] In a first aspect, this application provides a miniaturized multi-electrode printhead structure, including: a printhead body, a printing electrode assembly, and a controller;

[0042] The nozzle body is provided with a nozzle 110 and an insulating substrate 120;

[0043] The printing electrode assembly includes a focusing electrode 230, an accelerating electrode 220, and a deflecting electrode 210 arranged coaxially from top to bottom; an insulating substrate 120 is located between the focusing electrode 230 and the accelerating electrode 220, and the insulating substrate 120 is connected to the printhead 110 through the accelerating electrode 220 and the deflecting electrode 210.

[0044] The focusing electrode 230, the accelerating electrode 220 and the deflecting electrode 210 each have an inner cavity 234. The inner cavities 234 are connected to each other and are used to transport ink. The nozzle 110 of the printhead body is located at the tail end of the deflecting electrode 210. The nozzle 110 is connected to the inner cavity 234 of the deflecting electrode 210 and is used to spray ink droplets.

[0045] The controller is connected to the focusing electrode 230, the accelerating electrode 220 and the deflecting electrode 210 respectively. The focusing electrode 230 is used to apply a constant voltage to cause the ink to form and stabilize a Taylor cone at the exit of the printhead 110. The accelerating electrode 220 is used to apply a preset pulse electric field to stretch the liquid at the tip of the Taylor cone into a jet and break it into submicron droplets. The accelerating electrode 220 is also used to provide kinetic energy to the droplets. The deflecting electrode 210 is used to apply a transverse electrostatic field to change the jet direction of the droplets.

[0046] Among them, the focusing electrode 230, the accelerating electrode 220, and the deflecting electrode 210 all form a strong electric field with the grounded printing substrate below the printhead 110, such as Figure 4 As shown.

[0047] The insulating substrate 120 refers to the insulating layer used to isolate different electrodes. Specifically, it can be implemented using silicon dioxide or silicon nitride thin films. It is located between the focusing electrode 230 and the accelerating electrode 220 to ensure that there is no short circuit or electric field interference between the electrodes.

[0048] Here, the inner cavity 234 refers to the channel inside the electrode used for ink flow, which can be implemented using microfluidic channel etching technology. The various inner cavities 234 are interconnected, such as... Figure 3 As shown, this ensures that the ink is smoothly delivered from the inlet to the printhead 110.

[0049] The printhead 110 refers to the outlet from which the ink is finally ejected. Specifically, it can be implemented using a micro-machined glass nozzle or a silicon-based nozzle. It is located at the tail end of the deflection electrode 210 and is connected to the inner cavity 234 of the deflection electrode 210.

[0050] The controller is an electronic unit used to control the voltage of each electrode. Specifically, it can be implemented using a microprocessor-controlled power supply module. It is connected to the focusing electrode 230, the accelerating electrode 220, and the deflecting electrode 210 respectively to achieve independent electric field control.

[0051] The focusing electrode 230 is used to apply a constant voltage to cause the ink to form and stabilize a Taylor cone at the exit of the printhead 110. Specifically, a DC high voltage power supply can be used to achieve this. A stable Taylor cone is a prerequisite for the subsequent formation of uniform droplets.

[0052] The accelerating electrode 220 is used to apply a preset pulsed electric field to stretch the liquid at the tip of the Taylor cone into a jet and break it into submicron droplets. The accelerating electrode 220 is also used to provide kinetic energy to the droplets, which can be achieved by using a pulsed high-voltage power supply. The stretching and breaking of the jet are precisely controlled by the pulsed electric field to obtain submicron-sized droplets and give the droplets the necessary kinetic energy to achieve long-distance spraying.

[0053] The deflection electrode 210 is used to apply a transverse electrostatic field to change the jet direction of the droplet. Specifically, it can be achieved by using an adjustable DC high voltage power supply. The droplet is precisely deflected by the transverse electric field, thereby achieving high-precision positioning and patterning of the droplet on the substrate.

[0054] This solution achieves independent and precise control over droplet generation, acceleration, and deflection through a multi-electrode structure. The coaxial layered design of the focusing electrode 230, accelerating electrode 220, and deflecting electrode 210, along with the isolation provided by the insulating substrate 120, ensures the independence of the electric fields of each electrode. The constant voltage applied by the focusing electrode 230, the pulsed electric field applied by the accelerating electrode 220, and the lateral electrostatic field applied by the deflecting electrode 210 work together to form a stepped electric field with varying intensity between themselves and the printing substrate. This allows for precise control of the Taylor cone formation, jet stretching and breakage, and droplet deflection. This multi-level electric field control mechanism enables droplet sizes to overcome the physical limitations of nozzle diameter, achieving sub-micron level printing while ensuring the stability and high-precision positioning of the droplet trajectory.

[0055] Specifically, this solution introduces a multi-electrode structure to achieve independent and precise control over droplet generation, acceleration, and deflection, thereby solving the problems of low printing resolution, large droplet size, and poor positioning accuracy of existing single-electrode printheads.

[0056] The printhead body comprises a printhead 110 and an insulating substrate 120, providing basic support and insulation for the entire printhead 110 structure. The printing electrode assembly includes a focusing electrode 230, an accelerating electrode 220, and a deflecting electrode 210 arranged coaxially from top to bottom. This coaxial layered design is crucial for achieving multi-level electric field control. The insulating substrate 120 is located between the focusing electrode 230 and the accelerating electrode 220, ensuring electrical insulation between the different electrodes and preventing mutual interference of electric fields.

[0057] The focusing electrode 230, accelerating electrode 220, and deflecting electrode 210 each have an inner cavity 234. These cavities 234 are interconnected and used to transport ink, ensuring smooth ink flow from the printhead body to the printhead 110. The printhead 110 of the printhead body is located at the tail end of the deflecting electrode 210. The printhead 110 is connected to the inner cavity 234 of the deflecting electrode 210 and is used to eject ink droplets; this is the final outlet for the ink. The width of the deflecting electrode 210 gradually decreases from top to bottom. The tips of the accelerating electrode 220, deflecting electrode 210, and printhead 110 are arranged in a stepped pattern in the axial direction. This unique geometry is used to create a stepped electric field on the printing substrate below the printhead 110. This stepped electric field distribution is the basis for achieving submicron-level droplet generation and precise control, enabling more precise control of Taylor cone formation and jet breakage.

[0058] The controller is connected to the focusing electrode 230, accelerating electrode 220, and deflecting electrode 210, respectively, enabling independent electric field control of each electrode. The focusing electrode 230 applies a constant voltage to induce ink to form and stabilize a Taylor cone at the exit of the printhead 110. This is the first step in droplet generation; a stable Taylor cone is a prerequisite for the subsequent formation of uniform droplets. The accelerating electrode 220 applies a preset pulsed electric field to stretch the liquid at the tip of the Taylor cone into a jet and break it into submicron droplets. The accelerating electrode 220 also provides kinetic energy to the droplets. By precisely controlling the stretching and breaking of the jet through the pulsed electric field, submicron-sized droplets are obtained, and the droplets are given the necessary kinetic energy for long-distance ejection. The deflecting electrode 210 applies a transverse electrostatic field to change the ejection direction of the droplets. By precisely deflecting the droplets through the transverse electric field, high-precision positioning and patterning of the droplets on the substrate are achieved. This solution achieves independent and precise control over droplet generation, acceleration, and deflection through a multi-electrode structure and a stepped electric field distribution. This solves the problems of low printing resolution, large droplet size, and poor positioning accuracy of existing single-electrode nozzles, and enables sub-micron level printing and high-precision patterning.

[0059] In some embodiments, the deflection electrode 210 includes a deflection electrode insulator 212 whose width gradually decreases from top to bottom. A central groove 214 is provided at the lower part of the deflection electrode insulator 212 for detachably mounting the nozzle 110. A deflection electrode array is provided on the surfaces on both sides of the central groove 214. The deflection electrode array includes a left electrode 211 and a right electrode 213 that are insulated from each other. The width of both the left electrode 211 and the right electrode 213 gradually decreases from top to bottom. The deflection electrode insulator 212 is provided with two deflection electrode leads 215. The left electrode 211 and the right electrode 213 are respectively connected to a controller through the two deflection electrode leads 215. The controller is used to independently apply deflection voltage to the left electrode 211 and the right electrode 213.

[0060] The width of the deflection electrode 210 gradually decreases, causing the accelerating electrode 220, the deflection electrode 210, and the tip of the nozzle 110 to be arranged in a stepped manner, together forming an electric field with a stepped intensity distribution, such as... Figure 4 As shown, Figure 4 The horizontal axis in the figure represents distance in mm. This electric field distribution, in conjunction with the constant voltage applied by the focusing electrode 230, the pulsed electric field applied by the accelerating electrode 220, and the transverse electrostatic field applied by the deflecting electrode 210, allows for precise control of the Taylor cone formation, jet stretching and breakage, and droplet deflection. This multi-level electric field control mechanism enables droplet size to overcome the physical limitations of nozzle diameter, achieving sub-micron level printing while ensuring the stability and high-precision positioning of the droplet trajectory.

[0061] The deflection electrode insulator 212 is the main structural component of the deflection electrode 210. Its design, with its width gradually decreasing from top to bottom, helps optimize the electric field distribution for more effective droplet deflection. The central groove 214 allows the nozzle 110 to be installed in a detachable manner, greatly facilitating its maintenance and replacement. The deflection electrode array specifically refers to an electrode group consisting of a left electrode 211 and a right electrode 213, which are insulated from each other and symmetrically arranged on both sides of the central groove 214. The widths of the left electrode 211 and the right electrode 213 also gradually decrease from top to bottom to match the overall electric field design. Two deflection electrode leads 215 on the deflection electrode insulator 212 are used to connect the left electrode 211 and the right electrode 213 to the controller, allowing the controller to independently apply different deflection voltages to these two electrodes.

[0062] like Figure 2 As shown, the solution of this application refines the deflection electrode 210 into a left electrode 211 and a right electrode 213 that are insulated from each other, and enables the controller to independently apply deflection voltages to these two electrodes, thereby achieving fine control of the droplet ejection direction. Specifically, when the droplet needs to be deflected in a specific direction, the controller can apply voltages of different magnitudes or polarities to the left electrode 211 and the right electrode 213 according to a preset printing pattern or calibration data. For example, if the droplet needs to be deflected to the left, a relatively higher voltage can be applied to the right electrode 213, or a relatively lower voltage can be applied to the left electrode 211, and vice versa. The application of this differential voltage can form an asymmetric transverse electrostatic field in the space below the nozzle 110. This asymmetric electric field generates a resultant force on the charged droplet, thereby precisely guiding the droplet away from its initial straight ejection path, achieving more flexible and accurate ejection direction adjustment. Furthermore, the design of the deflection electrode insulator 212 and the left electrode 211 and right electrode 213 with gradually decreasing width from top to bottom helps to optimize the electric field distribution and further improve the deflection efficiency and accuracy.

[0063] Through the above technical solution, this application overcomes the limitations of a single deflection electrode in droplet direction control. The independently controlled left electrode 211 and right electrode 213 allow the printhead 110 to make more precise and flexible adjustments to the droplet ejection direction according to actual needs. This not only significantly improves printing accuracy and resolution, especially when printing complex patterns or multiple layers, but also enhances the adaptability of the printhead 110 to different printing tasks, thereby improving the overall performance and application range of the miniaturized multi-electrode printhead structure.

[0064] In some embodiments, the inner diameter of the nozzle 110 is 3μm-20μm.

[0065] The solution proposed in this application effectively balances ink fluid dynamics and electric field forces by precisely controlling the inner diameter of the printhead 110 within the range of 3μm-20μm. Within this inner diameter, the constant voltage applied by the focusing electrode 230 can more stably form a Taylor cone at the exit of the printhead 110, while the pulsed electric field applied by the accelerating electrode 220 can efficiently stretch and break the liquid at the tip of the Taylor cone into the desired submicron-sized droplets. This size range ensures moderate flow resistance of the ink inside the printhead 110, while providing a suitable interface for the electric field, thereby guaranteeing the accuracy and stability of the droplet formation process.

[0066] In some embodiments, the accelerating electrode 220 has a cylindrical structure, and a dielectric layer 222 is provided on the inner surface of the accelerating electrode 220. The dielectric layer 222 is used to insulate and isolate it from the deflection electrode 210. The accelerating electrode 220 is provided with a pulse signal input lead 223, which is used to connect to the controller.

[0067] Specifically, the accelerating electrode 220 adopts a cylindrical structure to create a uniform accelerating electric field in the space below the nozzle 110 and to provide structural support for the internal deflection electrode 210. The dielectric layer 222, which can be understood as an electrically insulating material layer, is specifically disposed on the inner surface of the accelerating electrode 220 to provide electrical insulation between the accelerating electrode 220 and the deflection electrode 210, thereby preventing electrical short circuits or electric field interference between them. In practical applications, the pulse signal input lead 223 is specifically used to transmit the pulse electrical signal generated by the controller to the accelerating electrode 220. For example, a highly conductive metal wire can be used. Its purpose is to ensure that the accelerating electrode 220 can accurately receive and respond to the controller's commands, thereby achieving the stretching, fracturing, and acceleration of the liquid at the tip of the Taylor cone.

[0068] The solution in this application effectively solves the insulation problem between the accelerating electrode 220 and the deflecting electrode 210 by designing the accelerating electrode 220 as a cylindrical structure and setting a dielectric layer 222 on its inner surface. Specifically, the cylindrical accelerating electrode 220 provides stable physical support and an electric field environment, while the dielectric layer 222 acts as an electrical insulation barrier, preventing direct electrical contact or electric field crosstalk between the accelerating electrode 220 and the deflecting electrode 210. Therefore, when the controller applies a pulse signal to the accelerating electrode 220 through the pulse signal input lead 223, the generated accelerating electric field can accurately act on the ink droplets without being interfered with by the deflecting electrode 210, ensuring the purity of the electric field and the accuracy of control. This design ensures that the electric field can function stably and efficiently during droplet formation and acceleration, thereby improving the accuracy and stability of droplet ejection.

[0069] In some embodiments, the dielectric layer 222 is an alumina composite insulating layer or a hafnium dioxide composite insulating layer, and the thickness of the dielectric layer 222 is 195nm-205nm.

[0070] Specifically, the dielectric layer 222 can be understood as a thin film providing electrical insulation, preferably made of alumina composite insulating layer or hafnium dioxide composite insulating layer. Both alumina (Al2O3) and hafnium dioxide (HfO2) are high dielectric constant materials with excellent insulation properties and chemical stability, effectively preventing electrical breakdown between the accelerating electrode 220 and the deflecting electrode 210, ensuring reliable electric field isolation. The composite insulating layer refers to an insulating layer composed of two or more materials, aiming to combine the advantages of different materials to further improve insulation performance, mechanical strength, or thermal stability. The thickness of the dielectric layer 222 is limited to the range of 195nm-205nm, with the aim of ensuring sufficient insulation strength while optimizing the electric field distribution to achieve precise control over the Taylor cone and droplet generation processes.

[0071] The solution in this application employs an alumina composite insulating layer or a hafnium dioxide composite insulating layer as the dielectric layer 222, and precisely controls its thickness within the range of 195nm-205nm, which significantly improves the insulation isolation effect between the accelerating electrode 220 and the deflecting electrode 210. It is precisely because these high dielectric constant materials possess excellent insulation properties that electric field interference and breakdown phenomena can be effectively avoided in the miniaturized structure. Simultaneously, precise thickness control ensures a more uniform and stable distribution of the electric field in the space below the nozzle 110, thereby providing a more reliable electric field environment for the stable formation of the Taylor cone, the stretching of the jet, and the breakup of submicron droplets.

[0072] In some embodiments, the focusing electrode 230 is provided with a mounting hole 231, a control signal interface 232, and an ink inlet 233. The ink inlet 233 is connected to the inner cavity 234 of the focusing electrode 230, the acceleration electrode 220, and the deflection electrode 210. The control signal interface 232 is connected to a controller, and the mounting hole 231 is used to connect to the motion device of the printing equipment.

[0073] Reference Figure 2Mounting holes 231 are located on one side of the focusing electrode 230. There may be two mounting holes 231, but this is not a limitation. A control signal interface 232 is located below the mounting hole 231. An ink inlet 233 is located on the other side of the focusing electrode 230, directly opposite the mounting hole 231 (to facilitate ink delivery into the ink inlet 233). The mounting holes 231 allow the focusing electrode 230 to be precisely and securely fixed to the moving parts of the printing equipment, ensuring the positional accuracy and stability of the printhead 110 during printing and preventing jetting deviations caused by mechanical shaking. The introduction of the control signal interface 232 ensures that the controller can reliably apply a constant voltage to the focusing electrode 230, thereby precisely controlling the formation and stabilization of the Taylor cone, which is fundamental to achieving high-quality droplet jetting. Simultaneously, the design of the ink inlet 233 and its connection to the inner cavity 234 of the printing electrode assembly ensures a continuous and stable ink supply to the printhead 110, preventing jetting abnormalities caused by ink supply interruptions or unevenness. It is precisely because of these dedicated interfaces that the focusing electrode 230 can play a core role in the miniaturized multi-electrode nozzle structure as a fully functional and easily integrated module.

[0074] Through the above technical solutions, the miniaturized multi-electrode printhead structure proposed in this application has achieved significant progress in terms of the integration and ease of operation of the focusing electrode 230. Specifically, the mounting hole 231 greatly simplifies the mechanical connection process between the printhead 110 and the printing equipment, improving assembly efficiency and positioning accuracy. The introduction of the control signal interface 232 ensures that the focusing electrode 230 can stably receive control signals, thereby achieving precise control of the Taylor cone formation process and improving the stability and repeatability of jetting. The design of the ink inlet 233 ensures the continuity and reliability of ink supply, effectively avoiding printing interruptions or quality degradation caused by ink supply problems. The combination of these additional features makes the entire miniaturized multi-electrode printhead structure more practical, reliable, and easy to use, thereby improving its overall performance in precision printing applications.

[0075] In some embodiments, the nozzle 110 includes a glass guide tube 111 and a glass nozzle 112 connected in sequence, the glass guide tube 111 being used to connect to the inner cavity 234 of the deflection electrode 210.

[0076] The solution in this application, by designing the printhead 110 as a structure including a glass guide tube 111 and a glass nozzle 112, ensures a clear and stable ink flow path within the printhead 110. The communication between the glass guide tube 111 and the inner cavity 234 of the deflection electrode 210 guarantees a smooth transition of ink from the inner cavity 234 of the electrode assembly to the printhead 110. The glass material's good chemical inertness and surface smoothness help reduce ink adhesion and clogging during flow, thereby maintaining a stable ink supply. The precise manufacturing of the glass nozzle 112 provides a dimensionally accurate outlet, which is crucial for forming a stable and uniform Taylor cone and subsequent droplet breakage.

[0077] The above technical solution, employing a combination of a glass guide tube 111 and a glass nozzle 112, effectively improves the stability of ink delivery and the accuracy of droplet formation at the printhead 110 exit. The superior properties of glass ensure smooth ink flow, reduce the risk of clogging, and thus improve the reliability and lifespan of the printhead 110. Furthermore, this structure facilitates finer control over droplet size and jet direction, thereby enhancing the printing accuracy and performance of the miniaturized multi-electrode printhead structure.

[0078] In some embodiments, the deflection electrode 210 is made of gold or molybdenum.

[0079] The solution in this application, by selecting gold or molybdenum as the material for the deflection electrode 210, ensures that the deflection electrode 210 possesses stable electrical and mechanical properties during operation. When the controller applies a dynamically changing voltage to the deflection electrode 210, the excellent conductivity of gold or molybdenum enables the efficient and uniform formation of a transverse electrostatic field on the surface of the deflection electrode 210. Furthermore, the good mechanical stability of these materials makes the deflection electrode 210 less prone to deformation or damage during long-term use, thereby ensuring the accuracy and stability of the applied transverse electrostatic field and thus ensuring precise control of the droplet ejection direction.

[0080] In some embodiments, the accelerating electrode 220 is made of gold or molybdenum.

[0081] The solution in this application, by limiting the material of the accelerating electrode 220 to gold or molybdenum, ensures that the accelerating electrode 220 has low resistance loss and fast response speed when a preset pulsed electric field is applied, thereby precisely controlling the formation and removal of the electric field. Simultaneously, the excellent corrosion resistance of these materials allows the accelerating electrode 220 to maintain stable contact with the ink for extended periods without performance degradation, ensuring stable Taylor cone formation, effective jet stretching, and accurate acceleration of submicron droplets, thereby maintaining the overall printing accuracy and stability of the printhead 110 structure.

[0082] Secondly, this application also provides a control method for a miniaturized multi-electrode nozzle structure, based on any of the miniaturized multi-electrode nozzle structures described above. The control method for the miniaturized multi-electrode nozzle structure includes the following steps:

[0083] First, a constant voltage is applied to the focusing electrode 230 via the controller to cause ink to form and stabilize a Taylor cone at the exit of the printhead 110;

[0084] Then, a pulse signal is applied to the acceleration electrode 220 by the controller, which stretches the liquid at the tip of the Taylor cone at the nozzle 110 outlet into a jet and breaks it into submicron droplets, and accelerates the droplets.

[0085] Finally, a dynamically changing voltage is applied to the deflection electrode 210 by the controller to change the direction of droplet ejection.

[0086] Specifically, the aforementioned control method aims to achieve precise control over the generation, acceleration, and deflection of ink droplets in a miniaturized multi-electrode printhead structure. The first step involves applying a constant voltage to the focusing electrode 230 via a controller. The focusing electrode 230 functions to form and stabilize a Taylor cone at the exit of the printhead 110. The stable formation of the Taylor cone is fundamental to subsequent droplet generation; its shape and stability directly affect the uniformity and size of the droplets. The application of this constant voltage ensures that the ink maintains a stable liquid surface morphology at the exit of the printhead 110, providing a controllable starting condition for the subsequent stretching and breaking processes.

[0087] Furthermore, in the second step, a pulse signal is applied to the accelerating electrode 220 via a controller. This pulse signal provides a momentary and powerful electric field that rapidly stretches the liquid at the tip of the already formed Taylor cone into a thin jet, causing the jet to break at a specific location, thus forming submicron-sized droplets. Simultaneously, the pulsed electric field provides the necessary kinetic energy to these newly formed droplets, allowing them to exit the nozzle 110 at a preset velocity. The frequency, amplitude, and duration of the pulse signal can be precisely adjusted according to the desired droplet size and velocity.

[0088] Finally, in the third step, a dynamically changing voltage is applied to the deflection electrode 210 via a controller. The deflection electrode array (e.g., the left electrode 211 and right electrode 213 described above) generates a transverse electrostatic field along the droplet's flight path through independently applied deflection voltages. This electrostatic field can precisely alter the droplet's ejection direction, guiding it to the target location. The dynamically changing voltage allows for real-time, fine control of the droplet's deflection angle, enabling high-resolution printing or patterning. For example, by adjusting the voltage difference between the left electrode 211 and the right electrode 213, the amount of transverse deflection of the droplet can be precisely controlled.

[0089] This application's solution effectively solves the problems of poor droplet stability, uneven size, and inaccurate directional control in traditional jet control by decoupling and sequentially controlling the droplet formation, acceleration, and deflection processes. First, the constant voltage of the focusing electrode 230 ensures the stable formation of the Taylor cone, providing a stable precursor for subsequent droplet generation. Second, the pulse signal of the accelerating electrode 220 precisely controls the stretching and breaking of the jet, thereby achieving uniform generation and acceleration of submicron-sized droplets and avoiding the randomness of droplet size. Finally, the dynamic voltage application mechanism of the deflection electrode 210 enables the droplet to be precisely deflected according to a preset trajectory during flight, overcoming the limitations of insufficient deflection accuracy in traditional methods. This step-by-step and coordinated control method allows the nozzle 110 structure to jet tiny droplets with high precision and high stability.

[0090] Through the above technical solution, this application enables precise and programmed control of the droplet ejection process in a miniaturized multi-electrode nozzle structure. Specifically, this control method ensures the stable formation of the Taylor cone, significantly improving the stability of the droplet generation process; through precise pulsed electric field control, it achieves uniform generation and efficient acceleration of sub-micron droplets, thereby improving printing resolution and efficiency; simultaneously, the dynamically changing deflection voltage allows for precise adjustment of the droplet ejection direction, greatly enhancing the flexibility and positioning accuracy of the ejection. These unique control effects collectively improve the overall performance of the miniaturized multi-electrode nozzle structure, giving it broader application potential in fields such as precision manufacturing and bioprinting.

[0091] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0092] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A miniaturized multi-electrode showerhead structure, characterized by, The nozzle body, the printing electrode group and the controller are included. The nozzle body is provided with a nozzle (110) and an insulating base (120). The printing electrode group includes a focusing electrode (230), an accelerating electrode (220) and a deflection electrode (210) coaxially arranged from top to bottom; the insulating base is located between the focusing electrode (230) and the accelerating electrode (220), and the insulating base (120) is connected with the nozzle (110) through the accelerating electrode (220) and the deflection electrode (210). The focusing electrode (230), the accelerating electrode (220) and the deflection electrode (210) each have an inner cavity (234) in communication with each other and used for conveying ink; the nozzle (110) of the nozzle body is located at the tail end of the deflection electrode (210), and the nozzle (110) is in communication with the inner cavity (234) of the deflection electrode (210) and used for spraying ink droplets. The controller is connected with the focusing electrode (230), the accelerating electrode (220) and the deflection electrode (210) respectively; the focusing electrode (230) is used for applying a constant voltage to form a Taylor cone at the outlet of the nozzle (110); the accelerating electrode (220) is used for applying a preset pulsed electric field to stretch the liquid at the tip of the Taylor cone into a jet and break it into sub-micron droplets, and also used for providing kinetic energy to the droplets; and the deflection electrode (210) is used for applying a transverse static electric field to change the spraying direction of the droplets. The deflection electrode (210) includes a deflection electrode insulator (212) with a gradually decreasing width from top to bottom; the lower part of the deflection electrode insulator (212) is provided with a center groove (214) used for detachably mounting the nozzle (110); a deflection electrode array is arranged on the surfaces on both sides of the center groove (214), and the deflection electrode array includes a left electrode (211) and a right electrode (213) insulated from each other; the width of each of the left electrode (211) and the right electrode (213) gradually decreases from top to bottom; the deflection electrode insulator (212) is provided with two deflection electrode lead wires (215), the left electrode (211) and the right electrode (213) are respectively connected with the controller through the two deflection electrode lead wires (215), and the controller is used for independently applying a deflection voltage to the left electrode (211) and the right electrode (213).

2. The miniaturized multi-electrode showerhead structure of claim 1, wherein, The inner diameter of the nozzle (110) is 3-20 μm.

3. The miniaturized multi-electrode showerhead structure of claim 1, wherein, The accelerating electrode (220) is in a cylindrical structure, and the inner side surface of the accelerating electrode (220) is provided with a dielectric layer (222) used for insulating and isolating the deflection electrode (210); the accelerating electrode (220) is provided with a pulse signal input lead wire (223) used for connecting the controller.

4. The miniaturized multi-electrode showerhead structure of claim 3, wherein, The dielectric layer (222) is an alumina composite insulating layer or a hafnium dioxide composite insulating layer, and the thickness of the dielectric layer (222) is 195-205 nm.

5. The miniaturized multi-electrode showerhead structure of claim 1, wherein, The focusing electrode (230) is provided with a mounting hole (231), a control signal interface (232), and an ink inlet (233) which communicates with the inner cavity (234) of the focusing electrode (230), the accelerating electrode (220), and the deflection electrode (210). The control signal interface (232) is connected with a controller, and the mounting hole (231) is used for connecting with a moving device of a printing device.

6. The miniaturized multi-electrode showerhead structure of claim 1, wherein, The nozzle (110) comprises a glass guide tube (111) and a glass nozzle (112) connected in sequence, and the glass guide tube (111) is used for connecting with the inner cavity (234) of the deflection electrode (210).

7. The miniaturized multi-electrode showerhead structure of claim 1, wherein, The material of the deflection electrode (210) is gold or molybdenum.

8. The miniaturized multi-electrode showerhead structure of claim 1, wherein, The material of the accelerating electrode (220) is gold or molybdenum.

9. A method of controlling a miniaturized multi-electrode showerhead structure, characterized by, The control method of the micro-sized multi-electrode nozzle structure according to any one of claims 1-8 comprises the following steps: First, a constant voltage is applied to the focusing electrode (230) by the controller to make the ink form a Taylor cone at the outlet of the nozzle (110); Then, a pulse signal is applied to the accelerating electrode (220) by the controller to stretch the liquid at the tip of the Taylor cone at the outlet of the nozzle (110) into a jet and break it to form sub-micron droplets, and accelerate the droplets; Finally, a dynamically changing voltage is applied to the deflection electrode (210) by the controller to change the jetting direction of the droplets.

Images