Piezoelectric sprayer chip processing technology and chip

Abstract

The invention relates to a piezoelectric nozzle chip processing technology and a chip, which are used for forming a chip, and the piezoelectric nozzle chip processing technology comprises the following steps: obtaining a silicon wafer, and taking the silicon wafer as a main body plate; etching a flow channel on the top surface of the main body plate; a through liquid outlet hole is etched in the bottom surface of the flow channel; obtaining SOI silicon wafers, and sequentially connecting the SOI silicon wafers on the top surface and the bottom surface of the main body plate; sequentially etching to remove the bottom silicon layer and the buried oxide layer of the SOI silicon wafer on the top surface of the main body plate to form a vibration plate; sequentially etching and removing a bottom silicon layer and a buried oxide layer of the SOI silicon wafer on the bottom surface of the main body plate to form a bottom plate; a through jet hole is etched in the bottom surface of the bottom plate, and the jet hole is communicated with the liquid outlet hole; and forming a piezoelectric structure on the top surface of the vibration plate. The runner is formed in the top surface of the main body plate, and the top end of the runner is blocked by combining the vibration plate, so that the surface smoothness of the main body plate is ensured, and the combination quality and the forming quality of each structure are ensured.

Description

Technical Field

[0001] The present application relates to the field of inkjet printing technology, and in particular to a processing technology and chip of a piezoelectric nozzle chip. Background Art

[0002] Inkjet printing, a contactless, pressureless, and maskless technology for display device processing, can precisely apply tiny droplets (in the picoliter or femtoliter range) to the desired location. The solvent evaporates, dries, and solidifies to form a thin film. This makes it easy to create extremely high-resolution display devices, especially when processing large-scale panels. Conventionally, piezoelectric printheads are used for printing.

[0003] In related technologies, a piezoelectric printhead consists of a chip and an ink cartridge. The ink cartridge supplies a functional fluid to the chip, which is then controlled by the chip to eject the fluid. Specifically, the chip consists of a top plate and a bottom plate joined together. A flow channel is created on the bottom surface of the top plate, a piezoelectric structure is placed on the top surface of the top plate, and a spray hole is created on the bottom plate. The top plate and the bottom plate are joined together to form a chip with a flow channel inside and a piezoelectric structure on top.

[0004] Chips are typically made from silicon wafers. After leaving the factory, silicon wafers are thick and have a smooth surface, making it easier to form structures like piezoelectric structures on them. Because the top plate's piezoelectric structure is formed on its top surface and its bottom surface is bonded to the base plate, the smoothness of both its top and bottom surfaces must be guaranteed.

[0005] Due to the thickness of the top plate, when etching the flow channel on the bottom surface of the top plate, the required depth of the etched flow channel is required to ensure that the top wall of the flow channel is thinner to form a vibration plate. This can easily cause the top plate to burn, affecting the quality of chip formation. Generally, the flow channel is etched after the silicon wafer is thinned after leaving the factory to reduce the etching depth.

[0006] However, due to the limitations of the silicon wafer thinning process, mechanical grinding will make the surface of the thinned silicon wafer rough, affecting the subsequent molding quality of the piezoelectric structure and adversely affecting the bonding quality of the top plate and the bottom plate, thereby affecting the molding quality of the chip. Summary of the Invention

[0007] The embodiment of the present application provides a processing technology and chip for a piezoelectric nozzle chip to solve the technical problem in the related art that the surface of the top plate of the chip is rough, which has an adverse effect on the forming of the piezoelectric structure, and has an adverse effect on the bonding quality of the top plate and the bottom plate, thereby affecting the forming quality of the chip.

[0008] In a first aspect, a process for processing a piezoelectric nozzle chip is provided, which is used to form the chip, and includes the following steps:

[0009] Obtaining a silicon wafer and using the silicon wafer as the main board;

[0010] Etching flow channels on the top surface of the main body plate;

[0011] Etching a liquid outlet hole through the bottom surface of the end of the flow channel;

[0012] Obtain an SOI silicon wafer, and sequentially connect the SOI silicon wafer to the top and bottom surfaces of the main plate, with the top and bottom surfaces of the main plate both bonded to the top silicon layer of the SOI silicon wafer;

[0013] The bottom silicon layer and buried oxide layer of the SOI silicon wafer on the top surface of the main plate are sequentially etched away, and the top silicon layer of the retained SOI silicon wafer forms a vibration plate on the top surface of the main plate;

[0014] The bottom silicon layer and buried oxide layer of the SOI silicon wafer on the bottom surface of the main plate are sequentially etched away, and the top silicon layer of the retained SOI silicon wafer forms a bottom plate on the bottom surface of the main plate;

[0015] A spray hole is etched through the bottom surface of the bottom plate, and the spray hole is connected to the liquid outlet hole;

[0016] A piezoelectric structure is formed on the top surface of the vibration plate.

[0017] In some embodiments, the depth of the flow channel is less than one-fifth of the thickness of the silicon main plate.

[0018] In some embodiments, while etching the flow channel on the top surface of the main plate, the method further includes:

[0019] At least one filter block is etched and formed in the flow channel. The filter block is fixed in the flow channel, and the filter block divides the inner channel of the flow channel into a plurality of paths.

[0020] In some embodiments, while etching the flow channel on the top surface of the main plate, the method further includes:

[0021] A flow limiting block is etched in the flow channel, and the filter block and the flow limiting block are arranged in sequence in the flow direction of the functional fluid.

[0022] In some embodiments, one end of the flow channel extends to the side surface of the main plate to form an opening.

[0023] In some embodiments, before etching the flow channel on the top surface of the main body plate, the method further includes forming a liquid inlet groove on the bottom surface of the main body plate;

[0024] While etching a liquid outlet hole through the bottom surface of the end of the flow channel, a communication hole communicating with the liquid inlet groove is also etched in the flow channel;

[0025] Wherein, both ends of the flow channel are closed.

[0026] In some embodiments, one end of the liquid inlet groove extends to the side of the main body plate to form an opening.

[0027] In some embodiments, the diameter of the injection hole is smaller than the diameter of the liquid outlet hole.

[0028] In some embodiments, forming a piezoelectric structure on the top surface of the vibration plate includes:

[0029] growing a first electrode layer on the top surface of the vibration plate;

[0030] growing a piezoelectric thin film layer on the first electrode layer;

[0031] growing a second electrode layer on the piezoelectric film layer;

[0032] The first electrode layer, the piezoelectric film layer, and the second electrode layer are etched on the vibration plate to form the first electrode, the piezoelectric film, and the second electrode.

[0033] The beneficial effects of the technical solution provided in the application include:

[0034] This embodiment of the present application provides a process for processing a piezoelectric nozzle chip. Because the flow channel is directly formed on the top surface of the main plate, the opening at the top of the flow channel is sealed by attaching a vibration plate to the top surface of the main plate, and a piezoelectric structure is arranged on the vibration plate. Therefore, there is no need to further deepen the flow channel to form thin-walled features. During flow channel processing, the etching depth is shallow, the etching difficulty is low, and the glue is not easily pasted or the main plate is not easily burned, thus ensuring the processing quality of the flow channel.

[0035] Since there is no need to reduce the difficulty of the process by thinning the main plate, the main plate is in the factory state, and the upper and lower surfaces of the main plate are smoother. When the main plate is placed on the processing table to etch structures such as the flow channel, the main plate is placed flatter during processing to ensure etching accuracy.

[0036] Since the top and bottom surfaces of the main plate are both bonded to the top silicon layer of the SOI silicon wafer, the top silicon layer is made of silicon as a whole, the main plate is also made of silicon, and no additional processing is required on the surface of the top silicon layer and the surface of the main plate. Therefore, the smoothness and flatness of the surface of the top silicon layer and the main plate are guaranteed, ensuring the quality of the bonding between the vibration plate and the bottom plate and the main plate, and thus ensuring the molding quality of the chip.

[0037] In addition, since a through liquid outlet hole is opened at the bottom of the flow channel to ensure better depth consistency of multiple liquid outlet holes, and a through injection hole is opened on the bottom plate, the consistency of multiple injection holes is better, which improves the molding quality of the chip. Therefore, the flow resistance value of the functional liquid in different injection holes is more consistent. When the piezoelectric structure drives the functional liquid to be ejected from multiple injection holes, it is not easy for the functional liquid in part of the flow channel to flow back, and the printing consistency and printing quality are guaranteed.

[0038] In a second aspect, a piezoelectric nozzle chip is provided, which is manufactured based on the piezoelectric nozzle chip manufacturing process as described above, and comprises:

[0039] a main plate, a flow channel is formed on a top surface of the main plate, a bottom of an end of the flow channel is provided with a through liquid outlet hole, and a liquid inlet end of the flow channel is in communication with an external liquid supply device;

[0040] a vibrating plate, a piezoelectric structure is formed on a top surface of the vibrating plate, the vibrating plate is attached to the top surface of the main plate, the vibrating plate blocks an opening at a top of the flow channel, and an acting end of the piezoelectric structure is arranged directly above the flow channel;

[0041] a bottom plate, a jet hole is formed on the bottom plate, the bottom plate is attached to a bottom surface of the main plate, and the jet hole is in communication with the liquid outlet hole.

[0042] Another embodiment of the present application provides a piezoelectric nozzle chip, which is manufactured based on the piezoelectric nozzle chip manufacturing process as described above, and thus has the same beneficial effects as the piezoelectric nozzle chip manufacturing process. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort.

[0044] Figure 1 A flow chart of the piezoelectric nozzle chip manufacturing process provided by the embodiment of the present application;

[0045] Figure 2 A schematic diagram of the piezoelectric nozzle chip provided by the embodiment of the present application;

[0046] Figure 3 A perspective view of the piezoelectric nozzle chip provided by the embodiment of the present application;

[0047] Figure 4 An exploded view of the piezoelectric nozzle chip provided by the embodiment of the present application;

[0048] Figure 5 An exploded view of the piezoelectric nozzle chip provided by the embodiment of the present application from another perspective.

[0049] In the figure: 1. Main plate; 2. Vibration plate; 3. Bottom plate; 4. Piezoelectric structure; 41. First electrode; 42. Piezoelectric film; 43. Second electrode; a. Flow channel; a1. Filter block; a2. Current limiting block; b. Liquid outlet; c. Liquid inlet tank; d. Connecting hole; e. Injection hole; A. SOI silicon wafer; A1. Top silicon layer; A2. Buried oxide layer; A3. Bottom silicon layer; B1. First electrode layer; B2. Piezoelectric film layer; B3. Second electrode layer. DETAILED DESCRIPTION

[0050] 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.

[0051] The present invention provides a processing technology and chip for a piezoelectric nozzle chip. By providing a flow channel on the top surface of a main plate and sealing the top of the flow channel with a vibration plate, the surface smoothness of the main plate is ensured, thereby ensuring the bonding quality and the molding quality of each structure. This application solves the technical problem in the related art that the rough surface of the chip top plate has an adverse effect on the molding of the piezoelectric structure, and has an adverse effect on the bonding quality of the top and bottom plates, thereby affecting the molding quality of the chip.

[0052] Reference Figure 1 , a processing technology for a piezoelectric nozzle chip includes steps S100-S800.

[0053] S100 , obtaining a silicon wafer, and using the silicon wafer as the main plate 1 .

[0054] S200 , etching a flow channel a on the top surface of the main plate 1 .

[0055] S300 , etching a liquid outlet hole b through the bottom surface of the end of the flow channel a.

[0056] S400 , obtaining SOI silicon wafer A, sequentially connecting SOI silicon wafer A to the top and bottom surfaces of main plate 1 , and bonding the top and bottom surfaces of main plate 1 to top silicon layer A1 of SOI silicon wafer A.

[0057] S500 , sequentially etching away the bottom silicon layer A3 and the buried oxide layer A2 of the SOI silicon wafer A on the top surface of the main plate 1 , and the remaining top silicon layer A1 of the SOI silicon wafer A forms a vibration plate 2 on the top surface of the main plate 1 .

[0058] S600 , sequentially etching away the bottom silicon layer A3 and the buried oxide layer A2 of the SOI silicon wafer A on the bottom surface of the main plate 1 , and retaining the top silicon layer A1 of the SOI silicon wafer A to form a bottom plate 3 on the top surface of the main plate 1 .

[0059] S700 , etching a penetrating injection hole e on the bottom surface of the bottom plate 3 , wherein the injection hole e is connected to the liquid outlet hole b.

[0060] S800 , forming a piezoelectric structure 4 on the top surface of the vibration plate 2 .

[0061] With this arrangement, the flow channel a is formed on the top surface of the main plate 1, and the top silicon layer A1 of the SOI silicon wafer A is bonded to the top surface of the main plate 1 to form the vibration plate 2. Therefore, there is no need to further deepen the flow channel a to form a thin-walled feature. When processing the flow channel a, the etching depth is shallow, the etching difficulty is low, and it is not easy to cause glue paste and burn the main plate 1, thereby ensuring the processing quality of the flow channel a.

[0062] Since there is no need to thin the main plate 1 to reduce the difficulty of the process, the main plate 1 is in the factory state, and the upper and lower surfaces of the main plate 1 are smoother. When the main plate 1 is placed on the processing table to etch structures such as the flow channel a, the main plate 1 is placed flatter during processing to ensure the etching accuracy.

[0063] Since the top and bottom surfaces of the main plate 1 are both bonded to the top silicon layer A1 of the SOI silicon wafer A, the top silicon layer A1 is made of silicon as a whole, the main plate 1 is also made of silicon, and the surface of the top silicon layer A1 and the surface of the main plate 1 do not require additional processing, so the smoothness and flatness of the surface of the top silicon layer A1 and the main plate 1 are guaranteed, ensuring the quality of the bonding between the vibration plate 2 and the bottom plate 3 and the main plate 1, and ensuring the molding quality of the chip.

[0064] In step S100 , a silicon wafer is obtained, and the silicon wafer is used as the main board 1 .

[0065] Specifically, silicon wafers are provided by manufacturers, and their surface smoothness is relatively good after they leave the factory.

[0066] Before processing the silicon wafer, the silicon wafer is cleaned. In this embodiment, the surface of the silicon wafer is cleaned by ultrasonic cleaning and plasma cleaning to ensure that the surface of the silicon wafer is clean.

[0067] In this embodiment, the thickness of the silicon plate serving as the main plate 1 is preferably less than 500 microns.

[0068] This configuration allows the chip size to be sufficiently reduced.

[0069] In step S200 , a flow channel a is etched on the top surface of the main plate 1 .

[0070] Specifically, a flow channel a is formed on the top surface of the main body plate 1 through an etching process. In this embodiment, a plurality of flow channels a are formed, and the plurality of flow channels a are arranged at intervals. The flow channels a are connected to an external ink cartridge, and the functional liquid is supplied to the flow channels a through the external ink cartridge.

[0071] Furthermore, the depth of the flow channel a is less than one fifth of the thickness of the silicon main plate 1. In this embodiment, the depth of the flow channel a is less than 100 microns.

[0072] This arrangement reduces the difficulty of etching the channel a by limiting the depth of the channel a, and avoids damage to the main plate 1 itself caused by etching the channel a too deeply, thereby reducing the molding cost of the channel a and making the processing accuracy of the channel a easier to ensure.

[0073] Among them, while etching the flow channel a on the top surface of the main plate 1, it also includes: etching at least one filter block a1 in the flow channel a, the filter block a1 is fixed in the flow channel a, and the filter block a1 divides the inner channel of the flow channel a into multiple paths.

[0074] Reference Figure 2-Figure 5 Specifically, the device includes at least one filter block a1, which is formed within flow channel a and divides the interior of flow channel a into multiple paths through which the functional fluid flows. This flow diversion reduces the flow path of each functional fluid stream, allowing more functional fluid to contact the inner wall of flow channel a.

[0075] In this embodiment, when only one filter block a1 is provided, it is positioned in the middle of the width of channel a, dividing channel a into two paths. When multiple filter blocks a1 are provided, they are spaced apart across the width of channel a. Multiple rows of filter blocks a1 may be arranged in the direction of flow of channel a, with each row staggered in the direction of flow to create a path for the functional fluid to pass through. This increases the area in contact with the functional fluid.

[0076] This arrangement ensures that when the functional liquid flows through the filter block a1, it contacts the filter block a1 as much as possible. After contacting the filter block a1, impurities in the functional liquid are easily attached to the filter block a1, thereby filtering out the impurities. After the functional liquid is filtered and decontaminated, it is not easy to cause clogging of the ejection hole e, thereby ensuring normal printing.

[0077] Among them, while etching the flow channel a on the top surface of the main plate 1, it also includes: etching a flow limiting block a2 in the flow channel a, and in the flow direction of the functional liquid, the filter block a1 and the flow limiting block a2 are arranged in sequence.

[0078] Reference Figure 2-Figure 5Specifically, a flow-limiting block a2 is formed in the flow channel a, and the filter block a1 and the flow-limiting block a2 are arranged in sequence in the flow direction of the functional liquid. The flow-limiting block a2 is used to limit the backflow of the functional liquid in the flow channel a. The content of the functional liquid in the flow channel a is maintained, and stable ink supply to the ejection hole e is ensured. The backflow of the functional liquid is avoided, and the flow disorder of the functional liquid is avoided to generate bubbles.

[0079] Preferably, the flow-limiting block a2 is arranged in the middle of the flow channel a, and the flow-limiting block a2 blocks part of the flow channel a. The cross-sectional area of the part of the flow channel a where the flow-limiting block a2 is arranged is smaller.

[0080] In this way, by arranging the flow-limiting block a2 in the flow channel a to reduce the communication area at this position, the functional liquid in the flow channel a is more likely to flow to the outlet hole b due to the pressure difference, so as to maintain stable ink supply to the ejection hole e.

[0081] In addition, under the action of the flow-limiting block a2, the functional liquid is not prone to backflow, the flow of the functional liquid is not prone to disorder, and bubbles are avoided, thereby ensuring the printing quality.

[0082] In the embodiment, the flow-limiting block a2 is connected to the side wall of the flow channel a, and the flow-limiting block a2 includes a guide inclined surface. The included angle between the guide inclined surface and the side surface of the flow channel a is arranged as an obtuse angle. In the flow direction of the functional liquid, the cross-sectional area of the part of the flow channel a where the flow-limiting block a2 is arranged gradually decreases along the flow direction of the functional liquid.

[0083] In this way, since the cross-sectional area of the part of the flow channel a where the flow-limiting block a2 is arranged gradually decreases along the flow direction of the functional liquid, the functional liquid is not directly blocked when flowing through the flow-limiting block a2. The impact and backflow of the functional liquid are avoided, so as to avoid bubbles of the functional liquid. The functional liquid flows more stably to the outlet hole b, and the ink supply to the ejection hole e is more stable.

[0084] In the step S300, the outlet hole b is etched through the bottom surface of the end of the flow channel a.

[0085] Referring to Figure 2-Figure 5 Specifically, the outlet hole b is arranged at the end of each flow channel a, and the outlet hole b is etched through the bottom surface of the flow channel a. Therefore, the depth consistency of the plurality of outlet holes b is facilitated to be controlled, so as to ensure the printing consistency.

[0086] In some embodiments, one end of the flow channel a extends to the side surface of the main plate 1 and is arranged as an opening.

[0087] The end of the flow channel a that is arranged as an opening on the side surface of the main plate 1 is in communication with the external ink cartridge, so as to leave an inlet for the functional liquid to flow into the flow channel a.

[0088] This arrangement places the inlet of flow channel a on the side of the main plate 1, eliminating the need for a liquid inlet on the surface of the vibration plate 2 to communicate with flow channel a. This improves the integrity of the vibration plate 2. This reduces the number of openings required on the vibration plate 2 and, by eliminating any notches on the top surface of the vibration plate 2, ensures the quality of the piezoelectric structure 4 when subsequently formed on the surface of the vibration plate 2, thereby improving the quality of the chip.

[0089] Reference Figure 2-Figure 5 In this embodiment, both ends of flow channel a are closed. Liquid inlet grooves c are provided on the bottom surface of the main body plate 1, communicating with flow channel a. The number of liquid inlet grooves c corresponds to the number of flow channels a. One end of the liquid inlet groove c extends to the side of the main body plate 1, forming an opening.

[0090] Specifically, before etching the flow channel a on the top surface of the main plate 1, a liquid inlet groove c is formed on the bottom surface of the main plate 1. Furthermore, while etching a liquid outlet hole b through the bottom surface at the end of the flow channel a, a communication hole d is also etched within the flow channel a, connecting to the liquid inlet groove c. The liquid inlet groove c and the communication hole d allow the functional liquid to be supplied to the liquid inlet groove c, allowing the functional liquid to overflow from the liquid inlet groove c into the flow channel a.

[0091] Reference Figure 2-Figure 5 Specifically, before forming the flow channels a, multiple liquid inlet grooves c are formed on the bottom surface of the main plate 1. The depth of the liquid inlet grooves c is less than 100 microns. One end of the liquid inlet groove c extends to one side of the main plate 1, forming an opening for communication with an external ink cartridge. The length of the liquid inlet groove c is shorter than the length of the flow channels a. The multiple liquid inlet grooves c correspond one-to-one with the multiple flow channels a. The vertical projections of the distal ends of the liquid inlet grooves c and the liquid inlet ends of the flow channels a overlap.

[0092] In addition, when processing the liquid outlet b, a penetrating communication hole d is simultaneously engraved on the bottom surface of the liquid inlet end of the flow channel a, and the communication hole d connects the liquid inlet groove c and the flow channel a.

[0093] With this arrangement, the liquid inlet groove c is processed first before the flow channel a is processed. Since the liquid inlet groove c occupies a small area on the main plate 1, the bottom surface of the main plate 1 is still relatively complete and the smoothness is guaranteed after the liquid inlet groove c is processed. When the flow channel a is subsequently processed, the bottom surface of the main plate 1 is in contact with the processing table, ensuring that the main plate 1 is stable and placed flat, thereby ensuring the accuracy of the etching process of the flow channel a and ensuring the molding quality of the flow channel a.

[0094] In addition, the connecting hole d is etched while the outlet hole b is being processed. Since the opening surfaces of the connecting hole d and the outlet hole b are both the bottom surface of the flow channel a, the connecting hole d and the outlet hole b can be formed simultaneously, saving processing steps.

[0095] By machining the liquid inlet groove c and the connecting hole d, the external ink cartridge delivers functional liquid to the liquid inlet groove c. Once the functional liquid accumulates to a certain height, it overflows from the inlet groove c and flows into the flow channel a. This prevents bubbles from forming when the functional liquid enters the flow channel a, ensuring that the functional liquid entering the liquid outlet hole b is bubble-free, thus ensuring print quality.

[0096] Moreover, since the liquid inlet groove c is connected to the external ink cartridge on the side of the main plate 1, the external ink cartridge supplies functional liquid to the flow channel a from the side inside the main plate 1, thereby ensuring the integrity of the top and bottom surfaces of the main plate 1 and the integrity of the vibration plate 2, thereby ensuring the quality of the subsequent molding structure on the top surface of the vibration plate 2.

[0097] Among them, step 400, obtain SOI silicon wafer A, connect SOI silicon wafer A to the top and bottom surfaces of main plate 1 in sequence, and the top and bottom surfaces of main plate 1 are bonded to the top silicon layer A1 of SOI silicon wafer A.

[0098] Specifically, the SOI silicon wafer A includes a top silicon layer A1, a buried oxide layer A2 and a bottom silicon layer A3, and the thickness of the top silicon layer A1 is smaller than that of the bottom silicon layer A3. Specifically, the thickness of the top silicon layer A1 meets the required thickness of the vibration plate 2.

[0099] The SOI silicon wafer A is fixed to the main plate 1 by bonding the top silicon layer A1 to the top surface or bottom surface of the main plate 1. In this embodiment, the top silicon layer A1 and the main plate 1 are fixed by silicon-silicon bonding.

[0100] In this embodiment, the order of bonding the SOI silicon wafer A on the top surface of the main body plate 1 and bonding the SOI silicon wafer A on the bottom surface of the main body plate 1 is not limited.

[0101] With this arrangement, SOI silicon wafer A is bonded to the top surface of main plate 1, shielding the upper opening of flow channel a. SOI silicon wafer A is bonded to the bottom surface of main plate 1, forming base plate 3 at the bottom of main plate 1. Furthermore, because the top surface of main plate 1 is relatively flat, and the surface of SOI silicon wafer A is also relatively flat, the bonding quality between SOI silicon wafer A and main plate 1 is improved.

[0102] It should be noted that when SOI silicon wafer A is formed, a buried oxide layer A2 and a backing layer are formed on the opposite surfaces of the silicon wafer, respectively. The buried oxide layer A2 and the backing layer are both silicon dioxide layers. The layer structure at this time is, in order, a backing layer, a bottom silicon layer A3, and a buried oxide layer A2. Finally, a top silicon layer A1 is generated on the surface of the buried oxide layer A2. It can be understood that the original structure of the bottom silicon layer A3 of the SOI silicon wafer A is a silicon layer and a backing layer, while the original structure of the top silicon layer A1 is a silicon layer. When the main plate 1 is bonded to the top silicon layer A1, the surfaces of the main plate 1 and the top silicon layer A1 are both original structures, and their surface smoothness is good, so silicon-silicon bonding can be directly used to ensure the bonding quality.

[0103] However, if the bottom silicon layer A3 is used to bond with the main plate 1, the backing layer on the surface of the bottom silicon layer A3 must be removed first. After the backing layer of the bottom silicon layer A3 is removed, the surface structure of the bottom silicon layer A3 is not the original structure, and its surface smoothness is difficult to guarantee. Therefore, the reliability of the bonding between the bottom silicon layer A3 and the main plate 1 is poor, and the yield rate is low.

[0104] Therefore, in this embodiment, the top silicon layer A1 is combined with the main plate 1 to ensure the bonding quality between the SOI silicon wafer A and the main plate 1.

[0105] In step S500 , the bottom silicon layer A3 and the buried oxide layer A2 of the SOI silicon wafer A on the top surface of the main plate 1 are sequentially etched away, and the top silicon layer A1 of the retained SOI silicon wafer A forms a vibration plate 2 on the top surface of the main plate 1 .

[0106] Specifically, the bottom silicon layer A3 is first etched away, and then the buried oxide layer A2 is etched away. Since the bottom silicon layer A3 is composed of silicon and the buried oxide layer A2 is composed of silicon dioxide, the etching selectivity of the bottom silicon layer A3 and the buried oxide layer A2 is different.

[0107] Therefore, when etching away the bottom silicon layer A3, the buried oxide layer A2 is not damaged, thereby maintaining the surface flatness and smoothness of the buried oxide layer A2. When etching away the buried oxide layer A2, the top silicon layer A1 is not damaged, thereby maintaining the surface flatness and smoothness of the top silicon layer A1. This not only allows a thinner vibration plate 2 to be formed on the top surface of the main plate 1, but also ensures that the surface flatness and smoothness of the vibration plate 2 are improved, thereby ensuring the precision and quality of the subsequent molding of the piezoelectric structure 4 on the surface of the vibration plate 2.

[0108] In step S600 , the bottom silicon layer A3 and the buried oxide layer A2 of the SOI silicon wafer A on the bottom surface of the main plate 1 are sequentially etched away, and the top silicon layer A1 of the retained SOI silicon wafer A forms the bottom plate 3 on the bottom surface of the main plate 1 .

[0109] Specifically, the bottom silicon layer A3 is first etched away, and then the buried oxide layer A2 is etched away. Since the bottom silicon layer A3 is composed of silicon and the buried oxide layer A2 is composed of silicon dioxide, the etching selectivity of the bottom silicon layer A3 and the buried oxide layer A2 is different.

[0110] Therefore, when etching away the bottom silicon layer A3, the buried oxide layer A2 is not damaged, thereby ensuring the surface flatness and smoothness of the buried oxide layer A2. When etching away the buried oxide layer A2, the top silicon layer A1 is not damaged, thereby ensuring the surface flatness and smoothness of the top silicon layer A1. Therefore, after the bottom plate 3 is formed, its surface smoothness is relatively good. When machining the surface structure of the vibration plate 2, the bottom plate 3 serves as a support surface, and the bottom plate 3 has a better fit with the surface of the machining table, thereby ensuring the molding quality of the surface structure of the vibration plate 2.

[0111] In this embodiment, the order of step S500 and step S600 is not limited.

[0112] In step S700 , a penetrating injection hole e is etched on the bottom surface of the bottom plate 3 , and the injection hole e is connected to the liquid outlet hole b.

[0113] Reference Figure 2-Figure 5 Specifically, a spray hole e is formed on the bottom surface of the base plate 3, connecting the spray hole e to the liquid outlet hole b. The diameter of the spray hole e is smaller than that of the liquid outlet hole b, and the center lines of the liquid outlet hole b and the spray hole e are collinear. Because the spray holes e are arranged throughout the base plate 3, the depth of the multiple spray holes e is more consistent.

[0114] With this arrangement, the liquid outlet b collects the functional liquid, ensuring the supply of the functional liquid to the ejection hole e and ensuring better consistency of the functional liquid in the ejection hole e each time printing, thereby ensuring printing quality.

[0115] Since a deep through-hole b is provided at the bottom of flow channel a, it is directly etched through, ensuring the depth consistency of multiple through-holes b. Furthermore, a deep through-hole e is provided on the bottom plate 3, achieving better consistency among the multiple through-holes ee and improving chip molding quality.

[0116] Since the consistency of multiple liquid outlet holes b is good and the depth consistency of multiple injection holes e is good, the flow resistance value of the functional liquid in different injection holes e is more consistent. When the piezoelectric structure 4 drives the functional liquid to be ejected from multiple injection holes e, it is not easy for the functional liquid in some flow channels a to flow back, and the printing consistency and printing quality are guaranteed.

[0117] In step S800 , a piezoelectric structure 4 is formed on the top surface of the vibration plate 2 .

[0118] Specifically, it includes steps S810-S840.

[0119] S810 , growing a first electrode layer B1 on the top surface of the vibration plate 2 .

[0120] S820 , growing a piezoelectric film B2 on the first electrode layer B1 .

[0121] S830 , growing a second electrode layer B3 on the piezoelectric film B2 .

[0122] S840 , etching the first electrode layer B1 , the piezoelectric film B2 , and the second electrode layer B3 on the vibration plate 2 to form the first electrode 41 , the piezoelectric film 42 , and the second electrode 43 .

[0123] In this arrangement, the first electrode layer B1, the piezoelectric film B2 and the second electrode layer B3 are sequentially grown on the surface of the vibration plate 2, and finally the first electrode layer B1, the piezoelectric film B2 and the second electrode layer B3 are etched to form the piezoelectric structure 4.

[0124] Specifically, the first electrode layer B1 and the second electrode layer B3 are formed by magnetron sputtering or electron beam evaporation; and the piezoelectric film B2 is formed by a sol-gel method.

[0125] The present embodiment provides a process for processing a piezoelectric nozzle chip. Since the flow channel a is directly formed on the top surface of the main plate 1, the opening at the top of the flow channel a is sealed by attaching the vibration plate 2 to the top surface of the main plate 1, and the piezoelectric structure 4 is arranged on the vibration plate 2. Therefore, there is no need to further deepen the flow channel a to form a thin-walled feature. During the processing of the flow channel a, the etching depth is shallow, the etching difficulty is low, and the glue is not easily pasted or the main plate 1 is not easily burned, thereby ensuring the processing quality of the flow channel a.

[0126] Since there is no need to thin the main plate 1 to reduce the difficulty of the process, the main plate 1 is in the factory state, and the upper and lower surfaces of the main plate 1 are smoother. When the main plate 1 is placed on the processing table to etch structures such as the flow channel a, the main plate 1 is placed flatter during processing to ensure the etching accuracy.

[0127] Since the top and bottom surfaces of the main plate 1 are both bonded to the top silicon layer A1 of the SOI silicon wafer A, the top silicon layer A1 is made of silicon as a whole, the main plate 1 is also made of silicon, and the surface of the top silicon layer A1 and the surface of the main plate 1 do not require additional processing, so the smoothness and flatness of the surface of the top silicon layer A1 and the main plate 1 are guaranteed, ensuring the quality of the bonding between the vibration plate 2 and the bottom plate 3 and the main plate 1, and ensuring the molding quality of the chip.

[0128] In addition, since a through liquid outlet hole b is opened at the bottom of the flow channel a to ensure better depth consistency of multiple liquid outlet holes b, and a through injection hole e is opened on the bottom plate 3, the consistency of multiple injection holes e is better, which improves the molding quality of the chip. Therefore, the flow resistance value of the functional liquid in different injection holes e is more consistent. When the piezoelectric structure 4 drives the functional liquid to be ejected from multiple injection holes e, it is not easy for the functional liquid in part of the flow channel a to flow back, and the printing consistency and printing quality are guaranteed.

[0129] Reference Figure 2-Figure 4 Another embodiment of the present application provides a piezoelectric nozzle chip, which is manufactured based on the above processing technology of the piezoelectric nozzle chip. The piezoelectric nozzle chip includes:

[0130] The main body plate 1 has a flow channel a on its top surface, a liquid outlet b extending through the bottom of the end of the flow channel a, and a liquid inlet end of the flow channel a is connected to an external liquid supply device.

[0131] The vibration plate 2 has a piezoelectric structure 4 formed on its top surface. The vibration plate 2 is attached to the top surface of the main plate 1. The vibration plate 2 blocks the top opening of the flow channel a, and the active end of the piezoelectric structure 4 is arranged directly above the flow channel a.

[0132] The bottom plate 3 is provided with a spray hole e. The bottom plate 3 is attached to the bottom surface of the main plate 1, and the spray hole e is connected to the liquid outlet hole b.

[0133] Another embodiment of the present application provides a piezoelectric nozzle chip. Since the piezoelectric nozzle chip is manufactured based on the processing technology of the above-mentioned piezoelectric nozzle chip, the beneficial effects of the piezoelectric nozzle chip are consistent with the beneficial effects of the processing technology of the above-mentioned piezoelectric nozzle chip, which will not be repeated here.

[0134] 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.

[0135] 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.

[0136] 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 processing technology for a piezoelectric nozzle chip, used for forming a chip, characterized in that: It includes the following steps: Obtaining a silicon wafer and using the silicon wafer as the main board; Etching flow channels on the top surface of the main body plate; Etching a liquid outlet hole through the bottom surface of the end of the flow channel; Obtain an SOI silicon wafer, and sequentially connect the SOI silicon wafer to the top and bottom surfaces of the main plate, with the top and bottom surfaces of the main plate both bonded to the top silicon layer of the SOI silicon wafer; The bottom silicon layer and buried oxide layer of the SOI silicon wafer on the top surface of the main plate are sequentially etched away, and the top silicon layer of the retained SOI silicon wafer forms a vibration plate on the top surface of the main plate; The bottom silicon layer and buried oxide layer of the SOI silicon wafer on the bottom surface of the main plate are sequentially etched away, and the top silicon layer of the retained SOI silicon wafer forms a bottom plate on the bottom surface of the main plate; A spray hole is etched through the bottom surface of the bottom plate, and the spray hole is connected to the liquid outlet hole; A piezoelectric structure is formed on the top surface of the vibration plate.

2. The processing technology of the piezoelectric nozzle chip according to claim 1, characterized in that: The depth of the flow channel is less than one fifth of the thickness of the silicon main plate.

3. The processing technology of the piezoelectric nozzle chip according to claim 1, characterized in that: While etching the flow channel on the top surface of the main plate, the method further comprises: At least one filter block is etched and formed in the flow channel. The filter block is fixed in the flow channel, and the filter block divides the inner channel of the flow channel into a plurality of paths.

4. The processing technology of the piezoelectric nozzle chip according to claim 3, characterized in that: While etching the flow channel on the top surface of the main plate, the method further comprises: A flow limiting block is etched in the flow channel, and the filter block and the flow limiting block are arranged in sequence in the flow direction of the functional fluid.

5. The processing technology of the piezoelectric nozzle chip according to claim 1, characterized in that: One end of the flow channel extends to the side surface of the main body plate to form an opening.

6. The processing technology of the piezoelectric nozzle chip according to claim 1, characterized in that: Before etching the flow channel on the top surface of the main body plate, the method further includes providing a liquid inlet groove on the bottom surface of the main body plate; While etching a liquid outlet hole through the bottom surface of the end of the flow channel, it also includes etching a communication hole in the flow channel that communicates with the liquid inlet groove; Wherein, both ends of the flow channel are closed.

7. The processing technology for the piezoelectric nozzle chip according to claim 5, characterized in that: One end of the liquid inlet groove extends to the side surface of the main body plate to form an opening.

8. The processing technology of the piezoelectric nozzle chip according to claim 1, characterized in that: The diameter of the injection hole is smaller than the diameter of the liquid outlet hole.

9. The processing technology of the piezoelectric nozzle chip according to claim 1, characterized in that: The piezoelectric structure is formed on the top surface of the vibration plate, comprising: growing a first electrode layer on the top surface of the vibration plate; growing a piezoelectric thin film layer on the first electrode layer; growing a second electrode layer on the piezoelectric film layer; The first electrode layer, the piezoelectric film layer, and the second electrode layer are etched on the vibration plate to form the first electrode, the piezoelectric film, and the second electrode.

10. A piezoelectric nozzle chip, characterized in that: The piezoelectric nozzle chip is manufactured based on the processing technology of any one of claims 1 to 9, and the piezoelectric nozzle chip includes: A main body plate, wherein a flow channel is provided on the top surface of the main body plate, a liquid outlet hole is provided at the bottom of the end of the flow channel, and the liquid inlet end of the flow channel is connected to an external liquid supply device; a vibration plate, wherein a piezoelectric structure is formed on the top surface of the vibration plate, the vibration plate is attached to the top surface of the main plate, the vibration plate blocks the top opening of the flow channel, and the active end of the piezoelectric structure is arranged directly above the flow channel; The bottom plate is provided with a spray hole, the bottom plate is attached to the bottom surface of the main body plate, and the spray hole is communicated with the liquid outlet.

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