A process for fabricating an electrode highly integrated electro-fluidic jet and an electro-fluidic jet

Abstract

The application relates to a processing technology of an electrode highly-integrated electro-fluid jet head and the electro-fluid jet head, and the processing technology comprises the following steps: processing a jet hole and a containing groove on the bottom surface of a glass substrate; opening a sunken ring groove on the bottom surface of the glass substrate to form a jet boss; and patterning a conductive layer, wherein the electrode ring of the conductive layer is respectively surrounded outside the jet boss, the lead wire of the conductive layer is connected with the electrode ring and extends into the containing groove to be connected with an external flexible circuit board. The electro-fluid jet head formed by the processing technology of the application is not easy to be polluted by the electrode ring outside the jet boss, and through processing of the wiring hole and the conductive ring, the flexible circuit board can be connected on the top surface of the glass substrate, the occupying structure on the bottom surface of the glass substrate is removed, the interference on the printing height adjustment is removed, and the normal operation of the printing processing is ensured.

Description

Technical Field

[0001] The present application relates to the field of inkjet printing technology, and in particular to a processing technology for an electrofluidic nozzle with highly integrated electrodes and the electrofluidic nozzle. Background Art

[0002] As a direct-write technology for additive manufacturing, inkjet printing offers advantages such as mask-free operation, flexible production, and high material utilization. It has promising applications in printed displays, printed circuits, printed solar cells, and other fields. Electrofluidic inkjet printing, which uses electric field force as its primary driving force, greatly enhances the ink's ability to drive the ink, enabling the printing of high-viscosity inks. Furthermore, because the ink is ejected locally on the curved liquid surface, the resulting droplet size can be much smaller than the nozzle diameter, significantly improving printing resolution. Electrofluidic inkjet printing overcomes the two major shortcomings of traditional inkjet printing and holds broad application prospects.

[0003] In related technologies, in order to achieve independent control of multiple nozzles of a nozzle, generally, electrode rings are arranged for multiple nozzles on the injection surface of the nozzle. The electrode rings are located at the nozzles. By separately controlling each electrode ring, the multiple nozzles can be independently controlled, thereby achieving work requirements such as shielding of defective nozzles and complex pattern printing.

[0004] However, when the electrode ring is arranged on the injection surface, on the one hand, when the functional liquid at the nozzle forms a Taylor cone, it may adhere to the electrode ring, corrode the electrode ring and affect the electric field at the nozzle, causing the nozzle to fail. On the other hand, when the external flexible circuit board is electrically connected to multiple electrode rings, one end of the flexible circuit board needs to be fixed and encapsulated on the injection surface of the nozzle. Due to the flexible circuit board on the injection surface of the nozzle, the printing height between the injection surface of the nozzle and the substrate is limited during printing, which interferes with the printing process and affects the normal printing process. Summary of the Invention

[0005] The embodiments of the present application provide a processing technology and an electrofluidic nozzle with highly integrated electrodes to solve the technical problems in related technologies that functional liquids easily corrode and damage electrode rings, and the packaging position of the circuit board interferes with the printing process, affecting normal printing processing.

[0006] In a first aspect, a process for manufacturing an electrofluidic ejector head with highly integrated electrodes is provided, comprising the following steps:

[0007] obtaining a glass substrate;

[0008] Processing an array of nozzle holes on the bottom surface of the glass substrate;

[0009] A sunken annular groove is machined around each nozzle hole on the bottom surface of the glass substrate to form a plurality of nozzle bosses;

[0010] Processing a receiving groove at the edge of the bottom surface of the glass substrate so that the bottom surface of the glass substrate is stepped, and the length direction of the receiving groove is consistent with the length direction of the arrangement of the nozzle holes;

[0011] A conductive layer is patterned on the bottom of the glass substrate, the conductive layer including a plurality of electrode rings and a plurality of leads, the plurality of electrode rings respectively surround the injection bosses, the plurality of leads are respectively connected to the plurality of electrode rings, and the plurality of leads all extend to the bottom of the receiving groove;

[0012] Covering the surface of the conductive layer with a protective layer, and keeping a portion of the conductive layer at the bottom of the receiving groove in an exposed state for connection with an external circuit board;

[0013] Complete the processing of the injection plate of the electrofluid nozzle.

[0014] In some embodiments, the step of machining a sunken annular groove around each nozzle hole on the bottom surface of the glass substrate comprises:

[0015] Laser etching to form a sunken ring groove;

[0016] The groove wall of the sinking ring groove is modified by CNC machining so that the groove wall slope of the sinking ring groove is 50-80 degrees.

[0017] In some embodiments, the height of the injection boss is no greater than the depth of the sinking annular groove, and the height of the injection boss ranges from 50 to 150 microns.

[0018] In some embodiments, the diameter of the injection end surface of the injection boss is 2-5 times the diameter of the injection hole.

[0019] In some embodiments, the thickness of the glass substrate is 2-5 times the depth of the receiving groove;

[0020] The depth of the receiving groove is not less than 150 microns.

[0021] In some embodiments, processing the receiving groove at the edge of the bottom surface of the glass substrate includes:

[0022] Laser etching forming receiving groove;

[0023] The groove wall of the receiving groove is modified by CNC machining so that the slope of the groove wall of the receiving groove is 50-80 degrees.

[0024] In some embodiments, the conductive layer is patterned on the bottom of the glass substrate, and the conductive layer includes a plurality of electrode rings and a plurality of leads. The plurality of electrode rings surround the injection bosses, and the plurality of leads are connected to the plurality of electrode rings, and the plurality of leads extend to the bottom of the receiving groove, including:

[0025] A conductive layer is formed on the bottom surface of the glass substrate using a metal lift-off process;

[0026] Forming an electrode ring of the conductive layer on the bottom surface of the glass substrate and arranging it around the nozzle;

[0027] The leads of the conductive layer are formed on the bottom surface of the glass substrate, the groove wall and the groove bottom of the receiving groove.

[0028] In some embodiments, the conductive layer is patterned on the bottom of the glass substrate, and the conductive layer includes a plurality of electrode rings and a plurality of leads. The plurality of electrode rings surround the injection bosses, and the plurality of leads are connected to the plurality of electrode rings, and the plurality of leads extend to the bottom of the receiving groove, including:

[0029] A conductive layer is formed on the bottom surface of the glass substrate using a metal lift-off process;

[0030] The electrode ring of the conductive layer is formed in the middle of the bottom of the sinking ring groove, with a safe distance between the electrode ring and the groove wall of the sinking ring, and the electrode ring is arranged around the nozzle hole;

[0031] The leads of the conductive layer are formed on the groove bottom and groove wall of the sinking ring groove, the bottom surface of the glass substrate, and the groove wall and groove bottom of the accommodating groove.

[0032] In some embodiments, the step of covering the surface of the conductive layer with a protective layer and maintaining a portion of the conductive layer at the bottom of the receiving groove exposed for connection to an external circuit board includes:

[0033] The passivation layer is covered on the surface of the conductive layer by using spray glue and metal stripping process;

[0034] A hydrophobic layer is sputtered on the surface of the passivation layer.

[0035] In some embodiments, after covering the surface of the conductive layer with a protective layer, the method further comprises:

[0036] A conductive protrusion is welded on the surface of the position where the lead is located at the bottom of the accommodating groove.

[0037] In a second aspect, an electrofluidic printhead is provided, comprising a spray plate and an ink cartridge connected to a top surface of the spray plate; the spray plate comprises:

[0038] A glass substrate, wherein a plurality of nozzle holes are formed through the bottom surface of the glass substrate, and a sunken annular groove is formed on the bottom surface of the glass substrate near the plurality of nozzle holes to form a plurality of injection bosses on the bottom of the glass substrate; an accommodating groove is formed on the edge of the bottom surface of the glass substrate, and a groove wall on one side of the accommodating groove is opened;

[0039] A plurality of electrode rings, each of which surrounds the outer sides of the plurality of injection bosses, and the electrode rings are arranged at the bottom of the sinking ring groove or the bottom surface of the glass substrate;

[0040] A plurality of lead wires, each of the plurality of lead wires corresponds to the plurality of electrode rings, one end of the lead wire is electrically connected to the electrode ring, and the other end of the lead wire extends to the bottom of the accommodating groove; wherein,

[0041] The parts of the plurality of leads at the bottom of the receiving groove are used for connection with an external flexible circuit board.

[0042] The beneficial effects of the technical solution provided by this application include:

[0043] The embodiment of the present application provides a process for processing an electrofluidic nozzle with a highly integrated electrode. A spray boss is formed by machining a sunken annular groove on the bottom surface of a glass substrate. An electrode ring is formed on the circumferential outer side of the spray boss. When a voltage is applied to the electrode ring and an electric field is applied to cause the functional liquid in the nozzle to be ejected, the functional liquid forms a Taylor cone on the spray surface of the spray boss. The functional liquid adheres to the spray surface of the spray boss. By machining the spray boss, a position for the functional liquid to form the Taylor cone is reserved. Since the electrode ring is located on the outer side of the spray boss, the functional liquid attached to the spray surface of the spray boss is not easily contaminated by the electrode ring, thereby ensuring the normal operation of the electrode ring and the normal operation of the corresponding nozzle. Furthermore, since the spray surface of the spray boss is an independent surface, the functional liquid can adhere to the spray surface of the spray boss in a more stable shape, forming a Taylor cone with a defined shape, thereby improving the consistency of the spray state of multiple nozzles.

[0044] In addition, by processing a receiving groove on the bottom surface of the glass substrate, the electrode ring is connected to the lead, and the lead extends to the bottom of the receiving groove. The external flexible circuit board is connected to multiple leads in the receiving groove to apply voltage to the multiple electrode rings to control the voltage at the nozzle, thereby achieving injection control of the nozzle. The placement position of the flexible circuit board is in the receiving groove, and the bottom of the flexible circuit board does not exceed the receiving groove. Therefore, the flexible circuit board and its packaging structure no longer occupy the space under the glass substrate, so as to support the glass substrate to be sufficiently close to the substrate to be printed, sufficiently reduce the printing height, and also increase the adjustment range of the printing height. The packaging position of the flexible circuit board will not affect the printing height, will not interfere with the printing process, and ensure the normal operation of the printing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0046] Figure 1 A flow chart of a process for manufacturing an electrofluidic nozzle with highly integrated electrodes provided in an embodiment of the present application;

[0047] Figure 2 A partial cross-sectional view of an electrofluidic showerhead provided in an embodiment of the present application;

[0048] Figure 3 A partial schematic diagram of the spray surface of the electrofluidic nozzle provided in an embodiment of the present application;

[0049] Figure 4 A partial cross-sectional view of an electric fluid ejector provided in another embodiment of the present application.

[0050] In the figure: 1. Glass substrate; 1a. Nozzle; 1b. Receiving groove; 1c. Sinking ring groove; 11. Injection boss; 2. Conductive layer; 21. Electrode ring; 22. Lead; 3. Protective layer; 31. Passivation layer; 32. Hydrophobic layer; 4. Conductive protrusion. DETAILED DESCRIPTION

[0051] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0052] The present invention provides a process for manufacturing an electrofluidic printhead with highly integrated electrodes and an electrofluidic printhead. The electrofluidic printhead formed using this process features an electrode ring on the outside of the ejection boss that is less susceptible to contamination. Furthermore, by processing a receiving groove to accommodate a flexible circuit board and removing the occupying structure beneath the glass substrate, interference with print height adjustment is eliminated, ensuring normal printing operation. This application addresses the technical issues in related technologies where functional fluids easily corrode and damage the electrode rings, and where the packaging position of the circuit board interferes with the printing process, impacting normal printing.

[0053] Reference Figure 1 A process for manufacturing an electrofluidic nozzle with highly integrated electrodes comprises the following steps:

[0054] S100 , obtaining a glass substrate 1 .

[0055] S200 , processing the array nozzle holes 1 a on the bottom surface of the glass substrate 1 .

[0056] S300 , a sunken annular groove 1 c is machined around each nozzle hole 1 a on the bottom surface of the glass substrate 1 to form a plurality of nozzle bosses 11 .

[0057] S400 , processing a receiving groove 1 b at the edge of the bottom surface of the glass substrate 1 so that the bottom surface of the glass substrate 1 is stepped, and the length direction of the receiving groove 1 b is consistent with the arrangement length direction of the nozzle holes 1 a.

[0058] S500. A conductive layer 2 is patterned on the bottom of the glass substrate 1. The conductive layer 2 includes a plurality of electrode rings 21 and a plurality of leads 22. The plurality of electrode rings 21 respectively surround the injection boss 11. The plurality of leads 22 are respectively connected to the plurality of electrode rings 21, and the plurality of leads 22 all extend to the bottom of the accommodating groove 1b.

[0059] S600 , covering the surface of the conductive layer 2 with a protective layer 3 , and keeping a portion of the conductive layer 2 at the bottom of the receiving groove 1 b exposed for connection to an external circuit board.

[0060] S700, completing the processing of the ejection plate of the electrofluidic ejector.

[0061] In this arrangement, the ejection boss 11 is formed by machining a sunken annular groove 1c on the bottom surface of the glass substrate 1. The electrode ring 21 is formed circumferentially outside the ejection boss 11. When a voltage is applied to the electrode ring 21, creating an electric field to eject the functional liquid from the nozzle 1a, the functional liquid forms a Taylor cone on the ejection surface of the ejection boss 11. The functional liquid adheres to the ejection surface of the ejection boss 11. The arrangement of the ejection boss 11 reserves space for the functional liquid to form a Taylor cone. Because the electrode ring 21 is located outside the ejection boss 11, the functional liquid adhering to the ejection surface of the ejection boss 11 is less likely to contaminate the electrode ring 21, thereby ensuring the proper functioning of the electrode ring 21 and the corresponding nozzle 1a. Furthermore, because the ejection surface of the ejection boss 11 is an independent surface, the functional liquid can adhere to the ejection surface of the ejection boss 11 in a more stable shape, forming a Taylor cone with a defined shape, thereby improving the consistency of the ejection state of the multiple nozzles 1a.

[0062] Furthermore, by machining a receiving groove 1b on the bottom surface of the glass substrate 1, the electrode rings 21 are connected to leads 22, which extend to the bottom of the receiving groove 1b. An external flexible circuit board is connected to multiple leads 22 within the receiving groove 1b to apply voltage to the multiple electrode rings 21, thereby controlling the voltage at the nozzle orifice 1a and thus controlling the jet from the nozzle 1a. The flexible circuit board is positioned within the receiving groove 1b, and the bottom of the flexible circuit board does not extend beyond the receiving groove 1b. Therefore, the flexible circuit board and its packaging structure no longer occupy space below the glass substrate 1, allowing the glass substrate 1 to be sufficiently close to the substrate to be printed, significantly reducing the printing height and increasing the adjustable range of the printing height. The packaging position of the flexible circuit board does not affect the printing height or interfere with the printing process, ensuring the normal operation of the printing process.

[0063] Reference Figure 2 and Figure 3, wherein, in step S100, a glass substrate 1 is obtained.

[0064] In this embodiment, the thickness of the receiving groove 1b is designed based on the thickness of the flexible circuit board itself, the thickness of the connection between the flexible circuit board and the conductive layer 2, and the thickness of the flexible circuit board package. The glass substrate 1 is selected to have a corresponding thickness according to the thickness of the receiving groove 1b.

[0065] In this embodiment, the thickness of the glass substrate 1 is 2-5 times the depth of the receiving groove 1b. This ensures that the glass substrate 1 is not too thin and therefore lacks strength. After the receiving groove 1b is formed in the glass substrate 1, it is less likely to deform or break. Furthermore, the glass substrate 1 is not too thick, which would result in the nozzle hole 1a being too long, thus reducing the possibility of nozzle hole 1a being clogged.

[0066] In this embodiment, the thickness of the receiving groove 1 b is not less than 150 micrometers, and the thickness of the glass substrate 1 is 300-800 micrometers.

[0067] Reference Figure 2 and Figure 3 In step S200 , an array of nozzle holes 1 a are processed on the bottom surface of the glass substrate 1 .

[0068] Specifically, the nozzle holes 1a are machined in the center of the bottom surface of the glass substrate 1 and arranged in multiple rows along the width of the glass substrate 1. Within each row, multiple nozzle holes 1a are spaced apart along the length of the glass substrate 1. In this embodiment, two rows of nozzle holes 1a are provided. Furthermore, in this embodiment, the receiving grooves 1b are formed at opposite edges of the bottom surface of the glass substrate 1, and the length of the receiving grooves 1b coincides with the length of the arrangement of the nozzle holes 1a.

[0069] In other embodiments, the glass substrate 1 is divided into multiple regions, each region is provided with a nozzle hole 1a and a receiving groove 1b, and the two rows of nozzle holes 1a are located between the two receiving grooves 1b. The glass substrate 1 can be subsequently divided into multiple regions through a scribing process to improve processing efficiency.

[0070] Furthermore, in this embodiment, the aperture of the nozzle 1a is 15-50 microns. If the aperture of the nozzle 1a is larger than 50 microns, the ejected droplets will be too large, affecting the printing accuracy; if the aperture of the nozzle 1a is too small, processing will be difficult and the nozzle 1a will be easily clogged.

[0071] Furthermore, the spacing between the nozzle holes 1a is 200-700 microns. By increasing the spacing between the nozzle holes 1a, the electric field crosstalk between the nozzle holes 1a is reduced, thereby ensuring printing accuracy.

[0072] In this embodiment, the nozzle hole 1a is processed into a through hole by using a laser etching process.

[0073] Laser processing is used to create marking points and nozzle holes 1a on the surface of the glass substrate 1. The locations of the nozzle holes 1a can be subsequently determined by capturing the marking points. Laser-induced etching of the nozzle holes 1a is used during this process to pre-form the structural features on the glass substrate 1, preventing subsequent laser processing from damaging the surface layer structure of the glass substrate 1.

[0074] Reference Figure 2 and Figure 3 In step S300 , a sunken annular groove 1 c is processed around each nozzle hole 1 a on the bottom surface of the glass substrate 1 to form a plurality of injection bosses 11 .

[0075] Specifically, the height of the ejection boss 11 is no greater than the depth of the sunken annular groove 1c, and the height range of the ejection boss 11 includes 50-150 microns. By arranging the ejection boss 11 and leaving a height difference between the ejection surface of the ejection boss 11 and the bottom of the sunken annular groove 1c, it is ensured that the functional liquid adheres to the ejection surface of the ejection boss 11 to form a Taylor cone. The functional liquid is not easy to spread to the bottom of the sunken annular groove 1c, and the functional liquid is not easy to accumulate and adhere to the circumferential outer side of the ejection boss 11, so as to keep the ejection surface of the ejection boss 11 in a clean state and not easy to affect the subsequent Taylor cone formation, thereby ensuring the ejection accuracy of the corresponding nozzle 1a. When the height of the ejection boss 11 is too high, it will affect the direction of the droplets ejected by the adjacent ejection boss 11, affecting the printing uniformity.

[0076] Specifically, step S300 includes steps S310 and S320.

[0077] S310, laser etching to form a sunken annular groove 1c;

[0078] S320, modifying the groove wall of the sunken annular groove 1c by numerical control machining so that the groove wall slope of the sunken annular groove 1c is 50-80 degrees.

[0079] This arrangement allows for laser etching of the sunken annular groove 1c, resulting in low cost and high processing efficiency. However, the verticality of the walls of the sunken annular groove 1c formed by laser etching is high, making subsequent deposition of the conductive layer 2 difficult. By modifying the walls of the sunken annular groove 1c using CNC machining to adjust the slope of the walls, when the slope of the sunken annular groove 1c is between 50 and 80 degrees, the conductive layer 2 is less likely to delaminate, curl, or even fall off when subsequently deposited on the walls, thereby improving molding quality.

[0080] Reference Figure 2 and Figure 3 Furthermore, after the sinking annular groove 1c is processed, the diameter of the injection end surface of the injection boss 11 is 2-5 times the diameter of the injection hole 1a.

[0081] This arrangement ensures that a stable Taylor cone is formed by designing the diameter of the ejection surface of the ejection boss 11 in accordance with the aperture of the ejection hole 1a, and that small-volume droplets can be printed. In this embodiment, printing of droplets smaller than 1 picoliter can be achieved.

[0082] In step S400 , a receiving groove 1 b is processed at the edge of the bottom surface of the glass substrate 1 so that the bottom surface of the glass substrate 1 is stepped, and the length direction of the receiving groove 1 b is consistent with the arrangement length direction of the nozzle holes 1 a.

[0083] In this way, by processing the receiving groove 1b, space for connecting and installing the flexible circuit board is reserved, thereby preventing the flexible circuit board from being directly packaged on the bottom surface of the glass substrate 1 and occupying the space on the bottom surface of the glass substrate 1.

[0084] Reference Figure 2 and Figure 3 The opening of the receiving groove 1b creates a stepped bottom edge of the glass substrate 1. It is understood that one side of the receiving groove 1b is open. The flexible printed circuit board (FPC) subsequently extends downward along the side of the glass substrate 1 and bends into the receiving groove 1b, facilitating its installation.

[0085] In this embodiment, the spray hole 1a, the receiving groove 1b and the sinking annular groove 1c can be processed together to improve the processing efficiency.

[0086] In some embodiments, the entire glass wafer is partitioned into multiple glass substrates 1, each glass substrate 1 is provided with a nozzle hole 1a and a receiving groove 1b, and after the conductive layer 2 and the protective layer 3 are processed, the entire glass wafer is divided into multiple glass substrates 1 by a scribing process to improve processing efficiency.

[0087] Specifically, step S400 includes steps S410 and S420.

[0088] S410 , laser etching to form the receiving groove 1b.

[0089] S420, modifying the groove wall of the receiving groove 1b by numerical control machining so that the groove wall of the receiving groove 1b has a slope of 50-80 degrees.

[0090] Laser etching of the receiving groove 1b is cost-effective and highly efficient. However, the walls of the laser-etched receiving groove 1b are highly vertical, making subsequent deposition of the conductive layer 2 difficult. By modifying the walls of the receiving groove 1b using CNC machining to adjust the slope of the walls, when the slope is between 50 and 80 degrees, the subsequent deposition of the conductive layer 2 on the walls is less likely to delaminate, curl, or even fall off, thereby improving the molding quality.

[0091] Reference Figure 2 and Figure 3In step S500, a conductive layer 2 is patterned on the bottom of the glass substrate 1, and the conductive layer 2 includes a plurality of electrode rings 21 and a plurality of leads 22. The plurality of electrode rings 21 respectively surround the injection boss 11, and the plurality of leads 22 are respectively connected to the plurality of electrode rings 21, and the plurality of leads 22 all extend to the bottom of the accommodating groove 1b.

[0092] Reference Figure 2 and Figure 3 Specifically, in this embodiment, the conductive layer 2 is formed on the bottom surface of the glass substrate 1, and the conductive ring of the conductive layer 2 surrounds the bottom surface of the glass substrate 1, and the lead 22 is formed on the bottom surface of the glass substrate 1 and the groove wall and groove bottom of the accommodating groove 1b.

[0093] In this embodiment, step S500 specifically includes:

[0094] A conductive layer 2 is formed on the bottom surface of the glass substrate 1 by adopting a metal lift-off process.

[0095] The electrode ring 21 of the conductive layer 2 is formed on the bottom surface of the glass substrate 1 and is arranged around the nozzle 1 a.

[0096] The lead wires 22 of the conductive layer 2 are formed on the bottom surface of the glass substrate 1 and the groove wall and groove bottom of the receiving groove 1 b.

[0097] Specifically, in this embodiment, the conductive layer 2 is formed using a metal lift-off process. This involves performing spray-on photolithography, electron beam evaporation, and lift-off cleaning steps to form the conductive layer 2 on the glass substrate 1. The conductive layer 2 is made of one or more of gold, silver, copper, aluminum, and chromium. In this embodiment, the conductive layer 2 comprises a laminated structure of chromium and gold. Specifically, a chromium layer is first sputtered, and then a gold layer is sputtered on the surface of the chromium layer. Preferably, the chromium layer has a thickness of 3-10 nanometers, and the gold layer has a thickness of 200-500 nanometers.

[0098] Reference Figure 2 and Figure 3 Specifically, the electrode ring 21 of the conductive layer 2 is formed on the bottom surface of the glass substrate 1 and is arranged around the sunken ring groove 1c. In this embodiment, the center lines of the electrode ring 21, the injection boss 11 and the injection hole 1a are consistent.

[0099] Furthermore, the ejection surface of the ejection boss 11 is higher than or flush with the bottom surface of the glass substrate 1. In this case, the electrode ring 21 is located below the ejection boss 11, forming a bottom-mounted electrode structure. Preferably, the ejection surface of the ejection boss 11 is higher than the bottom surface of the glass substrate 1, that is, the ejection boss 11 is located within the sunken annular groove 1c. This facilitates control of the depth of the sunken annular groove 1c and the height of the ejection boss 11. It also prevents the Taylor cone formed by the ejection surface of the ejection boss 11 from being attracted or contaminating the electrode ring 21 at the edge of the sunken annular groove 1c due to external factors.

[0100] Reference Figure 4 Specifically, in some embodiments, the conductive layer 2 is formed on the bottom of the sunken ring groove 1c and the bottom surface of the glass substrate 1, specifically, the electrode ring 21 of the conductive layer 2 is formed on the bottom of the sunken ring groove 1c, and the lead 22 is formed on the bottom and groove wall of the sunken ring groove 1c, the bottom surface of the glass substrate 1, and the groove wall and groove bottom of the accommodating groove 1b.

[0101] Reference Figure 4 In this embodiment, step S500 specifically includes:

[0102] A conductive layer 2 is formed on the bottom surface of the glass substrate 1 by adopting a metal lift-off process.

[0103] The electrode ring 21 of the conductive layer 2 is formed in the middle of the bottom of the sinking ring groove 1c. A safe distance is left between the electrode ring 21 and the groove wall of the sinking ring groove 1c, and the electrode ring 21 is arranged around the nozzle 1a.

[0104] The lead wires 22 of the conductive layer 2 are formed on the bottom and walls of the sunken annular groove 1 c , the bottom surface of the glass substrate 1 , and the walls and bottom of the receiving groove 1 b .

[0105] Reference Figure 4 Specifically, in this embodiment, a metal lift-off process is used to form the conductive layer 2 by photolithography. This involves performing spray photolithography, electron beam evaporation, and lift-off cleaning steps to form the conductive layer 2 on the glass substrate 1. The conductive layer 2 is made of one or more of gold, silver, copper, aluminum, and chromium. In this embodiment, the conductive layer 2 comprises a laminated structure of chromium and gold. Specifically, a chromium layer is first sputtered, and then a gold layer is sputtered on the surface of the chromium layer. Preferably, the chromium layer has a thickness of 3-10 nanometers, and the gold layer has a thickness of 200-500 nanometers.

[0106] Specifically, the electrode ring 21 of the conductive layer 2 is formed at the bottom of the sunken annular groove 1c. In this embodiment, the center lines of the electrode ring 21, the injection boss 11, and the injection hole 1a are aligned. A safe distance is left between the electrode ring 21 and the groove wall of the sunken annular groove 1c, preferably 20-100 microns.

[0107] This arrangement prevents the electrode ring 21 from being too close to the bottom edge of the sinking ring groove 1c. When the electrode ring 21 is formed using the metal stripping process, it prevents excessive deposition of photoresist at the corners of the sinking ring groove 1c, which affects the exposure effect. It ensures that the groove wall of the sinking ring groove 1c does not have an adverse effect on the conductive layer 2, and ensures that the conductive layer 2 is stably formed.

[0108] The leads 22 of the conductive layer 2 are formed on the walls of the sunken annular groove 1c, the bottom surface of the glass substrate 1, and the walls and bottom of the receiving groove 1b. The electrode ring 21 is electrically connected to the conductive ring. In this embodiment, the walls of the sunken annular groove 1c and the receiving groove 1b have a certain slope, which reduces the difficulty of forming the conductive layer 2 on the walls of the sunken annular groove 1c and the receiving groove 1b. The formed conductive layer 2 is more stable and less likely to fall off.

[0109] Reference Figure 4 In this embodiment, the ejection surface of the ejection boss 11 is flush with the bottom surface of the glass substrate 1, or the ejection surface of the ejection boss 11 is higher than the bottom surface of the glass substrate 1. Preferably, the ejection surface of the ejection boss 11 is flush with the bottom surface of the glass substrate 1, in which case an upper electrode structure is formed. This arrangement not only allows the ejection boss 11 to be formed by machining the sunken annular groove 1c, but also eliminates the need to machine the ejection boss 11 and adjust its height, thus saving processing costs. In addition, the ejection surface of the ejection boss 11 can be adjusted closer to the desired printing substrate, thereby expanding the print height adjustment range.

[0110] Reference Figure 2 and Figure 3 In step S600, a protective layer 3 is formed on the surface of the conductive layer 2, and a portion of the conductive layer 2 at the bottom of the receiving groove 1b is kept exposed for connection to an external circuit board.

[0111] A passivation layer 31 is coated on the surface of the conductive layer 2 by using a spraying and metal stripping process;

[0112] The hydrophobic layer 32 is sputtered on the surface of the passivation layer 31 .

[0113] Specifically, the passivation layer 31 is made of silicon dioxide and is patterned on the surface of the conductive layer 2 using a spray-on and metal lift-off process to protect the conductive layer 2. In this embodiment, the ends of the leads 22 at the bottom of the receiving groove 1b are not covered with the passivation layer 31 to reserve a connection position with the flexible circuit board. In this embodiment, the thickness of the passivation layer 31 is 300-600 nanometers.

[0114] Since the glass substrate 1 is provided with multiple nozzles 1a and the spacing between the nozzles 1a is small, the electrode rings 31 on the periphery of adjacent nozzles 1a are prone to electrical crosstalk when a DC pulse is passed through. Depositing the passivation layer 31 can prevent the generation of electrical crosstalk, oxidation of the electrode rings 31, and short circuits caused by ink droplet splashing.

[0115] The hydrophobic layer 32, made of parylene, is applied to the bottom surface of the glass substrate 1 via sputtering or vapor deposition, covering the structure on the bottom surface of the glass substrate 1 and also the passivation layer 31 to protect the conductive layer 2. In this embodiment, a mask is used to shield the end of the lead 22 at the bottom of the receiving groove 1b, allowing the hydrophobic layer 32 to be formed during sputtering. In this embodiment, the thickness of the hydrophobic layer 32 is 300-1000 nanometers.

[0116] The hydrophobic layer 32 can regulate the hydrophilic and hydrophobic properties at the nozzle hole 1 a , and has the functions of preventing oxidation and discharging static electricity, while not affecting the wire bonding process on the top surface of the glass substrate 1 .

[0117] Reference Figure 2 , wherein, after step 600, when the surface of the conductive layer 2 is covered with the protective layer 3, the method further includes:

[0118] The conductive protrusion 4 is welded on the surface of the lead 22 at the bottom of the receiving groove 1b.

[0119] In this configuration, by welding the conductive protrusion 4 at the end of the lead 22 to reserve a connection position for the flexible circuit board, the stability of the connection with the flexible circuit board is improved.

[0120] Specifically, the height of the conductive protrusion 4 is less than 20 micrometers. The conductive protrusion 4 is made of one of gold, silver, copper and aluminum.

[0121] When the flexible circuit board is subsequently installed, the thickness of the flexible circuit board is less than 80 microns and the sealing glue thickness is 20-30 microns.

[0122] In step S700, the processing of the ejection plate of the electrofluid ejector is completed.

[0123] Through steps S100 - S600 , the glass substrate 1 is processed into a spray plate of an electrofluidic printhead. Subsequently, an ink cartridge structure is mounted on the top surface of the glass substrate 1 to assemble the electrofluidic printhead.

[0124] The present invention provides a process for manufacturing an electrofluid ejector with a highly integrated electrode structure. A recessed annular groove 1c is machined on the bottom surface of a glass substrate 1 to form an ejection boss 11. An electrode ring 21 is formed circumferentially outside the ejection boss 11. When a voltage is applied to the electrode ring 21, creating an electric field to eject the functional liquid from the nozzle orifice 1a, the functional liquid forms a Taylor cone on the ejection surface of the ejection boss 11. The functional liquid adheres to the ejection surface of the ejection boss 11. The placement of the ejection boss 11 reserves space for the functional liquid to form a Taylor cone. Because the electrode ring 21 is located outside the ejection boss 11, the functional liquid adhering to the ejection surface of the ejection boss 11 is less likely to contaminate the electrode ring 21, ensuring the proper functioning of the electrode ring 21 and the corresponding nozzle orifice 1a. Furthermore, because the ejection surface of the ejection boss 11 is an independent surface, the functional liquid can adhere to the ejection surface of the ejection boss 11 in a more stable shape, forming a Taylor cone with a defined shape, thereby improving the consistency of the ejection state of the multiple nozzle orifices 1a.

[0125] Furthermore, by machining a receiving groove 1b on the bottom surface of the glass substrate 1, the electrode rings 21 are connected to leads 22, which extend to the bottom of the receiving groove 1b. An external flexible circuit board is connected to multiple leads 22 within the receiving groove 1b to apply voltage to the multiple electrode rings 21, thereby controlling the voltage at the nozzle orifice 1a and thus controlling the jet from the nozzle 1a. The flexible circuit board is positioned within the receiving groove 1b, and the bottom of the flexible circuit board does not extend beyond the receiving groove 1b. Therefore, the flexible circuit board and its packaging structure no longer occupy space below the glass substrate 1, allowing the glass substrate 1 to be sufficiently close to the substrate to be printed, significantly reducing the printing height and increasing the adjustable range of the printing height. The packaging position of the flexible circuit board does not affect the printing height or interfere with the printing process, ensuring the normal operation of the printing process.

[0126] Reference Figure 2 and Figure 3 In a second aspect, an electrofluidic printhead is provided, comprising a spray plate and an ink cartridge connected to a top surface of the spray plate; the spray plate comprises:

[0127] A glass substrate 1 is provided with a plurality of through-spray holes 1a on its bottom surface. A plurality of recessed annular grooves 1c are provided on the bottom surface of the glass substrate 1 near the plurality of spray holes 1a, thereby forming a plurality of spray bosses 11 on the bottom surface of the glass substrate 1. A receiving groove 1b is provided on an edge of the bottom surface of the glass substrate 1, and a groove wall of one side of the receiving groove 1b is provided.

[0128] A plurality of electrode rings 21, each of which surrounds the outer sides of the plurality of injection bosses 11, and is disposed at the bottom of the sinking ring groove 1c or the bottom surface of the glass substrate 1;

[0129] A plurality of lead wires 22, each corresponding to a plurality of electrode rings 21, one end of the lead wire 22 is electrically connected to the electrode ring 21, and the other end of the lead wire 22 extends to the bottom of the receiving groove 1b; wherein,

[0130] A plurality of leads 22 are located at the bottom of the receiving groove 1 b for connection with an external flexible circuit board.

[0131] Since the injection plate of the electrofluidic nozzle is processed by the processing technology of the electrofluidic nozzle with highly integrated electrodes, the beneficial effects of the electrofluidic nozzle are consistent with the beneficial effects of the processing technology of the electrofluidic nozzle with highly integrated electrodes, which will not be repeated here.

[0132] In the description of this application, it should be noted that the terms "upper" and "lower" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0133] It should be noted that, in this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0134] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. A process for manufacturing an electrofluidic nozzle with highly integrated electrodes, characterized in that: It includes the following steps: obtaining a glass substrate; Processing an array of nozzle holes on the bottom surface of the glass substrate; A sunken annular groove is machined around each nozzle hole on the bottom surface of the glass substrate to form a plurality of nozzle bosses; Processing a receiving groove at the edge of the bottom surface of the glass substrate so that the bottom surface of the glass substrate is stepped, and the length direction of the receiving groove is consistent with the length direction of the arrangement of the nozzle holes; A conductive layer is patterned on the bottom of the glass substrate, the conductive layer including a plurality of electrode rings and a plurality of leads, the plurality of electrode rings respectively surround the injection bosses, the plurality of leads are respectively connected to the plurality of electrode rings, and the plurality of leads all extend to the bottom of the receiving groove; Covering the surface of the conductive layer with a protective layer, and keeping a portion of the conductive layer at the bottom of the receiving groove in an exposed state for connection with an external circuit board; Complete the processing of the ejection plate of the electrofluidic nozzle; Among them, a metal lift-off process is used to form a conductive layer on the bottom surface of the glass substrate; The electrode ring of the conductive layer is formed on the bottom surface of the glass substrate and arranged around the nozzle hole; the lead wire of the conductive layer is formed on the bottom surface of the glass substrate, the groove wall and the groove bottom of the receiving groove; Alternatively, the electrode ring of the conductive layer is formed in the middle of the bottom of the sinking ring groove, with a safe distance between the electrode ring and the groove wall of the sinking ring, and the electrode ring is arranged around the nozzle; the lead wire of the conductive layer is formed on the groove bottom and groove wall of the sinking ring groove, the bottom surface of the glass substrate, and the groove wall and groove bottom of the accommodating groove.

2. The process for manufacturing an electrofluidic nozzle with highly integrated electrodes according to claim 1, characterized in that: The method of machining a sunken ring groove around each nozzle hole on the bottom surface of the glass substrate comprises: Laser etching to form a sunken ring groove; The groove wall of the sinking ring groove is modified by CNC machining so that the groove wall slope of the sinking ring groove is 50-80 degrees.

3. The process for manufacturing an electrofluidic nozzle with highly integrated electrodes according to claim 1, characterized in that: The height of the injection boss is not greater than the depth of the sinking ring groove, and the height range of the injection boss is 50-150 microns.

4. The process for manufacturing an electrofluidic nozzle with highly integrated electrodes according to claim 1, characterized in that: The diameter of the injection end surface of the injection boss is 2-5 times the diameter of the injection hole.

5. The process for manufacturing an electrofluidic nozzle with highly integrated electrodes according to claim 1, characterized in that: The thickness of the glass substrate is 2-5 times the depth of the receiving groove; The depth of the receiving groove is not less than 150 microns.

6. The process for manufacturing an electrofluidic nozzle with highly integrated electrodes according to claim 1, characterized in that: The step of machining a receiving groove at the edge of the bottom surface of the glass substrate comprises: Laser etching forming receiving groove; The groove wall of the receiving groove is modified by CNC machining so that the slope of the groove wall of the receiving groove is 50-80 degrees.

7. The process for manufacturing an electrofluidic nozzle with highly integrated electrodes according to claim 1, characterized in that: The method of covering the surface of the conductive layer with a protective layer and keeping a portion of the conductive layer at the bottom of the receiving groove exposed for connection with an external circuit board includes: The passivation layer is covered on the surface of the conductive layer by using spray glue and metal stripping process; A hydrophobic layer is sputtered on the surface of the passivation layer.

8. The process for manufacturing an electrofluidic nozzle with highly integrated electrodes according to claim 1, characterized in that: After the protective layer is covered on the surface of the conductive layer, the method further comprises: A conductive protrusion is welded on the surface of the position where the lead is located at the bottom of the accommodating groove.

9. An electrofluidic showerhead manufactured based on the processing technology of the electrofluidic showerhead with highly integrated electrodes according to any one of claims 1 to 8, characterized in that: The invention comprises an ejection plate and an ink cartridge connected to the top surface of the ejection plate; the ejection plate comprises: A glass substrate, wherein a plurality of nozzle holes are formed through the bottom surface of the glass substrate, and a sunken annular groove is formed on the bottom surface of the glass substrate near the plurality of nozzle holes to form a plurality of injection bosses on the bottom of the glass substrate; an accommodating groove is formed on the edge of the bottom surface of the glass substrate, and a groove wall on one side of the accommodating groove is opened; A plurality of electrode rings, each of which surrounds the outer sides of the plurality of injection bosses, and the electrode rings are arranged at the bottom of the sinking ring groove or the bottom surface of the glass substrate; A plurality of lead wires, each of the plurality of lead wires corresponds to the plurality of electrode rings, one end of the lead wire is electrically connected to the electrode ring, and the other end of the lead wire extends to the bottom of the accommodating groove; wherein, The parts of the plurality of leads at the bottom of the receiving groove are used for connection with an external flexible circuit board.

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