Manufacturing method of nozzle plate

Abstract

To improve the manufacturing method of nozzle sheets and the corresponding inkjet wafer structure in the prior art, this invention proposes a nozzle sheet manufacturing method, comprising the following steps: preparing a nozzle sheet material; coating the nozzle sheet material with photoresist; exposing and developing the photoresist to pattern the nozzle sheet material and the photoresist, defining a nozzle, and forming a nozzle exit diameter using an etching process; etching the nozzle sheet material and the photoresist to define a nozzle inlet diameter; removing the photoresist from the nozzle sheet material to form a nozzle sheet; and preparing an inkjet wafer and placing the nozzle sheet on the inkjet wafer. The nozzle inlet diameter is greater than or equal to the nozzle exit diameter.

Description

[Technical Field]

[0001] This case relates to a method for manufacturing a nozzle plate, and more specifically, to an improved process for manufacturing a nozzle plate to accommodate more detailed inkjet patterns and manufacturing costs. [Previous Technology]

[0002] Inkjet printing technology, commonly known as "Inkjet Printing," is a widely used printing technology whose history dates back to the 1950s when Hewlett-Packard (HP) in the UK invented it. Since then, inkjet printing technology has developed rapidly, making inkjet printers the mainstream technology for home and commercial printing. Inkjet printers have many advantages, including: low cost, especially economical for home and small business use; high print quality, providing high-resolution and high-quality images, especially for photos or pictures; ease of use, inkjet printers are easy to install, and most inkjet printers can print via computer or mobile devices. Combined with the multi-functional office machines (including fax, photocopying, and scanning) that have emerged in recent years, they can quickly expand the flexibility of office paperwork.

[0003] Existing inkjet printing technology has increasingly diverse applications, ranging from inkjet printers used in schools and offices to 3D printing or industrial printing on various material surfaces (such as label printing), all of which have various inkjet chips optimized for different needs. For example, US Patent 9016836B2 describes an inkjet chip structure. Figure 3 of this '836 case reveals that its architecture includes a stacked structure composed of components such as a protective layer, a resistive layer, a thermally resistive layer, and a silicon carbide layer. Ink flows from the lower layer of the inkjet chip upward through an ink channel through the aforementioned stacked structure and then into the ink supply chamber to supply the printing needs, enabling modern inkjet printing technology to achieve the goal of printing high-resolution and high-quality images.

[0004] Furthermore, the nozzle plate in the inkjet chip has nozzles for ink ejection. For inkjet printing technology, in order to achieve the above-mentioned goal of high resolution and high quality images during printing, the structure of the nozzles and the corresponding manufacturing method will directly affect the physical characteristics of the ink flow. For example, whether the atomization is uniform and whether the flow rate can be stably controlled will directly affect the printing effect. In the current market, with increasingly higher requirements for printing quality, in order to make the printed pattern more detailed, there is a certain demand for miniaturizing the size of the nozzles. In the past, the manufacturing of nozzle plates used laser drilling and cutting technology, which is insufficient for applications that require further miniaturization of the nozzle size. In view of this, proposing a novel nozzle plate structure and corresponding manufacturing method has become the subject of this invention. [Summary of the Invention]

[0005] The main objective of this invention is to provide a method for manufacturing a nozzle sheet, comprising a nozzle sheet and a corresponding inkjet chip. By manufacturing the nozzle sheet structure using a semiconductor process, the nozzle size in the manufactured nozzle sheet meets the requirements of detail and resolution of the pattern during inkjet printing. At the same time, the structure of the ink droplet generator can simultaneously integrate the ink supply chamber and the ink outlet on the barrier layer. This maintains the performance of printing high-resolution and high-quality images in traditional inkjet printing technology, while also making the manufacturing process more convenient. Furthermore, the cost of the nozzle sheet manufactured by this chip manufacturing method will be significantly reduced, further meeting the cost requirements of various office, commercial, and industrial applications, and achieving the goal of improving printing quality in industry as described in this invention. For detailed technical solutions, please refer to the following description.

[0006] One of the generalized embodiments of this case is to provide a method for manufacturing a nozzle sheet, applied to an inkjet wafer structure, comprising the following steps: preparing a nozzle sheet material; coating a photoresist material on a nozzle sheet material; exposing and developing the photoresist material to pattern the nozzle sheet material and the photoresist material to create a nozzle, and defining a nozzle exit diameter by an etching process; etching the nozzle sheet material and the photoresist material to define a nozzle inlet diameter; removing the photoresist material from the nozzle sheet material to form a nozzle sheet; and preparing an inkjet wafer and disposing the nozzle sheet on the inkjet wafer; wherein the nozzle inlet diameter is greater than or equal to the nozzle exit diameter.

[0007] According to one embodiment of the present invention, when the thickness of the nozzle material is between 43 μm and 57 μm, the nozzle inlet diameter minus the nozzle outlet diameter is greater than or equal to 12 μm. According to another embodiment of the present invention, when the thickness of the nozzle material is between 20 μm and 30 μm, the nozzle inlet diameter minus the nozzle outlet diameter is greater than or equal to 8 μm.

[0008] According to an embodiment of the present invention, the inkjet chip includes: a plurality of ink droplet generators, wherein each ink droplet generator includes a chip substrate, a thermal barrier layer, a heating resistance layer, a conductive layer, a protective layer, and a barrier layer stacked in sequence to form a stacked structure, wherein an ink supply chamber is provided between the protective layer and the barrier layer, and an ink outlet is provided at the top of the ink supply chamber for connecting the ink outlet plate to the nozzle.

[0009] In the above embodiments of the present invention, the thermal barrier layer is an insulating material formed on the wafer substrate, the heating resistance layer is a resistive material formed on the thermal barrier layer, the conductive layer is a conductive material, and a portion of the conductive layer is formed on the heating resistance layer, a portion of the protective layer is formed on the heating resistance layer, the other portion of the protective layer is formed on the conductive layer, and the barrier layer is a polymer material formed on the protective layer. In addition, the ink supply chamber and the ink outlet are integrally formed in the barrier layer, and the ink is supplied from the side of the ink supply chamber through an ink supply channel in a direction parallel to the plane of the stacked structure.

Implementation Method

[0012] This invention will be described in detail with reference to preferred embodiments and viewpoints so that the reader can fully understand how these embodiments are implemented. However, those skilled in the art will understand that this invention can also be implemented without these details. Furthermore, this invention can also be used and implemented by other specific embodiments, and the various details set forth in this specification can be applied based on different needs, and various modifications or changes can be made without departing from the spirit of this invention. Therefore, this invention will be described with reference to preferred embodiments and viewpoints. Such descriptions are for explaining the structure of this invention and are only for illustration and not for limiting the scope of the patent application of this invention. The terminology used in the following description will be interpreted in the broadest and most reasonable way so that it can be used with the detailed description of a particular embodiment of this invention. Those skilled in the art can adjust the structure of this invention to meet the needs of actual industry according to manufacturing or application requirements, which is hereby stated in advance.

[0013] Please refer to Figures 1, 2A, 2B, 2C, and 2D. To achieve the purpose of this invention, this application proposes a method for manufacturing an orifice sheet 10, applied to an inkjet wafer structure 1, comprising the following steps: In process S1, an orifice sheet material 501 is prepared; in process S2, a photoresist material 502 is coated on the orifice sheet material 501; in process S3, the photoresist material 502 is exposed and developed to pattern the orifice sheet material 501 and the photoresist material 502, forming an orifice 11, and an orifice outlet diameter D is defined by an etching process; in process S4, the orifice sheet material 501 and the photoresist material 502 are etched to define an orifice inlet diameter L; and in process S5, the photoresist material 502 is removed from the orifice sheet material 501 to form an orifice sheet 10; wherein the orifice inlet diameter L is greater than or equal to the orifice outlet diameter D. According to one aspect and physical characteristics of the present invention, for inkjet printing, when the nozzle inlet diameter L is less than or equal to the nozzle outlet diameter D, the nozzle 11 will generate a large flow resistance. When the ink remains in the nozzle 11 due to the aforementioned flow resistance, the inkjet chip 20 will need to heat the ink with greater heat energy in order to eject the ink out of the nozzle 11, which will be more energy-intensive. Therefore, in the manufacturing process of the nozzle chip 10, the condition that the nozzle inlet diameter L is greater than or equal to the nozzle outlet diameter D can make the inkjet process more energy-efficient. Since the ejection energy is small, it can also make the fineness of the pattern more precisely controlled during the inkjet process. The manufacturing process can also achieve the purpose that is insufficient when the traditional method of using laser drilling and cutting to form the nozzle chip 10 needs to be further miniaturized.

[0014] In an embodiment of the present invention, the nozzle sheet manufacturing method further includes execution process S6, preparing an inkjet chip 20, and forming a nozzle sheet 10 on the inkjet chip 20 to form an inkjet chip structure 1.

[0015] As described above, according to one embodiment of the present invention, when the thickness of the nozzle sheet material 501 is between 43 μm and 57 μm, the nozzle inlet diameter L - nozzle outlet diameter D is greater than or equal to 12 μm. According to another embodiment of the present invention, when the thickness of the nozzle sheet material 501 is between 20 μm and 30 μm, the nozzle inlet diameter L - nozzle outlet diameter D is greater than or equal to 8 μm. This allows inkjet printing to optimize the size of the nozzle 11 according to the application requirements. Specifically, according to embodiments of the present invention, the specifications of the nozzle sheet material 501, the nozzle inlet diameter L, and the nozzle outlet diameter D enable the inkjet wafer structure 1 to correspond to a resolution DPI (Dots Per Inch) ranging from 150 to 48000 DPI.

[0016] Please refer to Figures 3, 4, and 5. According to an embodiment of the present invention, the nozzle plate 10 can be disposed on the surface of the inkjet wafer 20 in a bonded manner, or it can be formed on the inkjet wafer 20 by a semiconductor process. Figure 4 is a cross-sectional view of Figure 3, and Figure 5 is a three-dimensional view formed by slightly rotating Figure 4 (omitting the nozzle plate 10). The inkjet wafer 20 further includes: a plurality of ink droplet generators 22, including a wafer substrate 228, a thermal barrier layer 221, a heating resistance layer 222, a conductive layer 223, a protective layer 224, and a barrier layer 225 stacked to form a stacked structure, with each nozzle 11 corresponding to the opposite ink droplet generator 22. In addition, according to an embodiment of the present invention, the wafer substrate 228 can be fabricated using a 3- to 20-inch wafer semiconductor process. In the above-described embodiments of the present invention, the thermal barrier layer 221 is an insulating material formed on the wafer substrate 228, the heating resistance layer 222 is a resistive material formed on the thermal barrier layer 221, the conductive layer 223 is a conductive material and is partially formed on the heating resistance layer 222 to form a heating resistor 222a, and the protective layer 224 is partially formed on the heating resistor 222a formed by the heating resistance layer 222. An ink supply chamber 226 is provided between the protective layer 224 and the barrier layer 225, and the top of the ink supply chamber 226 has an ink outlet 227 to connect to the nozzle 11. Furthermore, other portions of the protective layer 224 are formed on the conductive layer 223, while the barrier layer 225 is a polymer material and is formed on the protective layer 224. The ink supply chamber 226 and the ink outlet 227 are integrally formed in the barrier layer 225. The ink is supplied from the side of the ink supply chamber 226 through an ink supply channel 21 in a direction parallel to the plane of the stacked structure, so as to reduce the flow path of the ink during supply and increase the speed of ink supply. The ink flow in Figure 4 is the above-mentioned embodiment in which the ink is supplied from the side of the ink supply chamber 226 in a direction parallel to the plane of the stacked structure.

[0017] According to the present invention, the material of the nozzle plate 501 may be selected from any combination of one or more of polyimide (PI), metal, and ceramic.

[0018] According to the present invention, the thermal barrier layer 221 is an insulating material formed on the wafer substrate 228. The material of the wafer substrate 228 is a silicon wafer, and the insulating material can be selected from any combination of one or more of field oxide (FOX), silicon dioxide (SiO2), silicon nitride (Si3N4) and silicon phosphorus glass (PSG).

[0019] According to the present invention, the heating resistance layer 222 is a resistive material formed on the thermal barrier layer 221. The resistive material may be any combination of one or more of the following: polysilicon, tantalum aluminide (TaAl), tantalum (Ta), tantalum nitride (TaN), tantalum disilicide (Si2Ta), carbon (C), silicon carbide (SiC), indium tin oxide (ITO), zinc oxide (ZnO), cadmium sulfide (CdS), hafnium diboride (HfB2), titanium tungsten alloy (TiW), and titanium nitride (TiN).

[0020] According to the present invention, the conductive layer 223 is a conductive material, which is any combination of one or more of aluminum (Al), aluminum-copper alloy (AlCu), aluminum-silicon alloy (AlSi), gold (Au), palladium (Pd), palladium-silver alloy (PdAg), platinum (Pt), aluminum-silicon-copper (AlSiCu), niobium (Nb), vanadium (V), hafnium (Hf), titanium (Ti), zirconium (Zr), and yttrium (Y).

[0021] According to the present invention, a portion of the protective layer 224 is formed on the heating resistance layer 222, and the other portion of the protective layer 224 is formed on the conductive layer 223. The protective layer 224 is composed of a second protective layer 224B stacked on top of a first protective layer 224A below, and a third protective layer 224C on top of the second protective layer 224B (that is, the stacking order from bottom to top is the first protective layer 224A, the second protective layer 224B, and the third protective layer 224C). The first protective layer 224A is made of silicon nitride (Si3N4); the second protective layer 224B is a passivation material selected from one of silicon nitride (Si3N4), silicon dioxide (SiO2), titanium dioxide (TiO2), hafnium dioxide (HfO2), zirconium dioxide (ZrO2), tantalum pentoxide (Ta2O5), rhenium heptaoxide (Re2O7), niobium pentoxide (Nb2O5), uranium pentoxide (U2O5), tungsten trioxide (WO3), silicon oxynitride (Si4O5N3), and silicon carbide (SiC); and the third protective layer 224C is a metallic material, which is any combination of one or more of tantalum (Ta), tantalum nitride (TaN), titanium nitride (TiN), and tungsten nitride (TiW). The number and materials of the aforementioned protective layers 224 can be appropriately adjusted and modified according to the degree of erosion of each material by the ink, the thermal stress on the inkjet chip structure 1 caused by temperature changes when the heating resistor 222a is operating, and the required product life cycle of the inkjet chip structure 1. Similarly, the first protective layer 224A, the second protective layer 224B, and the third protective layer 224C described in this invention are for illustrative purposes only and are not intended to limit the scope of the invention.

[0022] The barrier layer 225 is a polymer material formed on the protective layer 224. The polymer material is one of polyimide or organic plastic material. The ink supply chamber 226 and the ink outlet 227 are integrally formed in the barrier layer 225. The bottom of the ink supply chamber 226 is connected to the protective layer 224, and the ink outlet 227 at the top of the ink supply chamber 226 is connected to the nozzle 11.

[0023] According to an embodiment of the present invention, the ink supply channels 21 in the inkjet chip 20 can be 1-6 colors. If single-color ink is provided, this single-color ink can be cyan (C): Cyan, magenta (M): Megenta, yellow (Y): Yellow, and black (K): Black. In other embodiments of the present invention, the ink supply channels 21 can be 6 colors, providing black (K): Black, cyan (C): Cyan, magenta (M): Megenta, yellow (Y): Yellow, light cyan (LC): Light cyan, and light magenta (LM): Light magenta. Of course, in another embodiment, the ink supply channels 21 can also be 4 colors, providing cyan (C): Cyan, magenta (M): Megenta, yellow (Y): Yellow, and black (K): Black. The number of ink supply channels 21 or the colors provided can be replaced or modified according to actual application requirements.

[0024] In summary, the nozzle sheet manufacturing method of this invention includes a nozzle sheet and a corresponding inkjet chip. By manufacturing the nozzle sheet using a semiconductor process, it improves upon the limitations of traditional laser-manufactured nozzle sheets, where the nozzle size is restricted, thus failing to meet the requirements for detailed patterns during printing. This enhances the performance of inkjet printing technology in printing high-resolution and high-quality images, while also making the manufacturing process more convenient. Furthermore, the cost of the nozzle sheet manufactured using this process is significantly reduced, further meeting the cost requirements of various office, commercial, and industrial applications. This achieves the purpose of improving printing quality in industry, making it highly applicable to industrial applications. This invention can be modified in various ways by those skilled in the art, but all modifications will not deviate from the scope of protection sought in the appended patent application. [Simplified Explanation of the Diagram]

[0010] The following detailed description of the invention and the schematic diagrams of the embodiments should enable the invention to be more fully understood; however, it should be understood that this is limited to the reference for understanding the application of the invention and not to limiting the invention to a particular embodiment.

[0011] Figure 1 illustrates the process flow of the nozzle plate manufacturing method. Figure 2A illustrates the process flow of the nozzle plate manufacturing method. Figure 2B illustrates the process flow of the nozzle plate manufacturing method. Figure 2C illustrates the process flow of the nozzle plate manufacturing method. Figure 2D illustrates the process flow of the nozzle plate manufacturing method. Figure 3 illustrates the configuration of the nozzle plate and inkjet chip in the inkjet chip structure. Figure 4 shows the stacked structure of the inkjet chip structure as seen from a three-dimensional perspective. Figure 5 shows the stacked structure of the ink droplet generator as viewed from the side in Figure 4 (the top nozzle plate is omitted).

Claims

1. A method for manufacturing a nozzle sheet, comprising: preparing a nozzle sheet material; coating a photoresist material onto the nozzle sheet material; exposing and developing the photoresist material to pattern the nozzle sheet material and the photoresist material, forming a plurality of nozzles, and defining a nozzle exit diameter by an etching process; etching the nozzle sheet material and the photoresist material to define a nozzle inlet diameter; removing the photoresist material from the nozzle sheet material to form a nozzle sheet; and preparing an inkjet wafer, disposing the nozzle sheet on the inkjet wafer to form an inkjet wafer structure, wherein the inkjet wafer further includes a plurality of droplet generators, the plurality of droplet generators further including a wafer substrate, a thermal barrier layer, a heating resistance layer, a conductive layer, a protective layer, and a barrier layer stacked to form a stacked structure; wherein... The conductive layer is partially formed on the heating resistance layer, the protective layer is partially formed on the heating resistance layer, and the remaining portion of the protective layer is formed on the conductive layer. An ink supply chamber and an ink outlet are integrally formed in the barrier layer, and the bottom of the ink supply chamber is connected to the protective layer, while the top of the ink outlet is connected to the plurality of nozzles. The nozzle inlet diameter is greater than or equal to the nozzle outlet diameter. When the thickness of the nozzle sheet material is between 43 μm and 57 μm, the nozzle inlet diameter - nozzle outlet diameter is greater than or equal to 12 μm. The protective layer includes a first protective layer, a second protective layer, and a third protective layer, which are stacked sequentially from bottom to top. The first protective layer is made of silicon nitride (Si3N4), the second protective layer is a passivation material, and the third protective layer is a metallic material.

2. The method for manufacturing a nozzle plate as described in claim 1, wherein the material of the nozzle plate may be selected from any combination of one or more of polyimide (PI), metal, and ceramic.

3. The method for manufacturing an inkjet chip as described in claim 1, wherein the resolution range corresponding to the inkjet chip structure is between 150 and 48000 DPI.

4. A method for manufacturing a nozzle sheet, comprising: preparing a nozzle sheet material; coating a photoresist material onto the nozzle sheet material; exposing and developing the photoresist material to pattern the nozzle sheet material and the photoresist material, forming a plurality of nozzles, and defining a nozzle exit diameter by an etching process; etching the nozzle sheet material and the photoresist material to define a nozzle inlet diameter; removing the photoresist material from the nozzle sheet material to form a nozzle sheet; and preparing an inkjet wafer, disposing the nozzle sheet on the inkjet wafer to form an inkjet wafer structure, wherein the inkjet wafer further includes a plurality of droplet generators, the plurality of droplet generators further including a wafer substrate, a thermal barrier layer, a heating resistance layer, a conductive layer, a protective layer, and a barrier layer stacked to form a stacked structure; wherein... The conductive layer is partially formed on the heating resistance layer, the protective layer is partially formed on the heating resistance layer, and the remaining portion of the protective layer is formed on the conductive layer. An ink supply chamber and an ink outlet are integrally formed in the barrier layer, and the bottom of the ink supply chamber is connected to the protective layer, while the top of the ink outlet is connected to the plurality of nozzles. The nozzle inlet diameter is greater than or equal to the nozzle outlet diameter. When the thickness of the nozzle sheet material is between 20 μm and 30 μm, the nozzle inlet diameter minus the nozzle outlet diameter is greater than or equal to 8 μm. The protective layer includes a first protective layer, a second protective layer, and a third protective layer, which are stacked sequentially from bottom to top. The first protective layer is made of silicon nitride (Si3N4), the second protective layer is a passivation material, and the third protective layer is a metallic material.

5. The method for manufacturing a nozzle plate as described in claim 4, wherein the material of the nozzle plate may be selected from any combination of one or more of polyimide (PI), metal, and ceramic.

6. The method for manufacturing an inkjet chip as described in claim 4, wherein the resolution range corresponding to the inkjet chip structure is between 150 and 48000 DPI.

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