Patent Application
20250236984
The present invention relates to an electroplating apparatus and an electroplating method, and more specifically, to an electroplating apparatus and an electroplating method, which can plate a target on one side of a substrate while moving an anode horizontally, and consistently maintain the concentration of iron ions in a plating solution through the injection of inert gas when the plating solution is supplied during the plating process, thereby providing excellent plating quality.
An organic light-emitting diode (OLED) is a thin-film light-emitting diode (LED) made of a film of organic compounds, which has a light-emitting layer emits light in response to an electric current. Common OLED display devices emit light by electrically connecting fluorescent or phosphorescent organic compounds, enabling image expression by operating N×M organic light-emitting cells.
The organic light-emitting cell typically has a structure composed of an anode (ITO), an organic thin film, and a cathode (metal). To enhance the balance between electrons and holes and improve light-emission efficiency, the organic thin film has a multilayer structure that includes a light-emitting layer (EML), an electron transport layer (ETL), and a hole transport layer (HTL), and may also include an electron injecting layer (EIL) and a hole injecting layer (HIL).
To achieve full-color implementation in the OLED device, the red (R), green (G), and blue (B) light-emitting layers must be individually patterned. To pattern the light-emitting layer, a fine metal mask (FMM) is typically used.
The fine metal mask primarily uses invar, an alloy of steel and nickel, in consideration of thermal expansion and others.
The primary production method for invar alloy (36% Ni-64% Fe) or super invar alloy (32% Ni-63% Fe-5% Co) used in making fine metal masks is cold rolling. However, obtaining thin sheets with thicknesses below 50 microns through cold rolling requires a multi-stage rolling process, which makes the process lengthy and complex, leading to high manufacturing costs. Additionally, cold-rolled invar thin sheets of less than 50 microns are limited to widths of less than 500 mm, there are significant difficulties in applying as large-area processing materials.
The above problems result in increased manufacturing costs for OLED devices requiring thicknesses of 20 μm or less and reduced process yields for large-area OLED display production, further increasing costs and hindering advancements in display technology.
Recently, a production method for producing invar alloys for fine metal masks via electroforming using a master with a mask pattern formed on one surface thereof.
The general method for producing invar alloy plating for fine metal masks using the electroforming method includes: positioning an anode electrode plate and a master, which serves as the cathode, in parallel to be opposite each other inside a plating tank; supplying a plating solution (electrolyte) into an inner space of the plating tank; connecting an anode power supply to the anode electrode plate and a cathode power supply to the master; and applying current to form a plating layer (invar alloy) on one side of the master.
Thereafter, the plating layer is separated from the master, subjected to post-processing, and used to manufacture the fine metal mask. In this instance, the mask pattern pre-formed on the master's surface is transferred to the plating layer.
Here, the plating layer formed on one surface of the master is the invar alloy, which typically consists of an iron-nickel alloy (36% Ni-64% Fe), though the composition can vary depending on the intended purpose. The anode electrode plate is usually made of nickel or an insoluble anode, and the plating solution is formed to maintain iron ions (Fe2+) dissolved.
At this point, the iron ions dissolved in the plating solution are continuously consumed by adhering to the master, which serves as the cathode, to form the plating layer. Therefore, maintaining an accurate concentration of iron ions in the plating solution is a critical factor in determining the quality of the invar alloy.
However, iron oxide (4Fe3++3O2→2Fe2O3) can be produced by oxygen (O2) generated from the reaction at the insoluble anode (H2O→½O2+2H++2e) and Fe3+ generated from the spontaneous reaction of Fe2+ (Fe2+→Fe3++e−). So, the iron oxide generated through the above decreases the reduction of Fe3+ back to iron ions by the reduction reaction of Fe3+ (Fe3++e−→Fe2+).
As described above, when the reduction in the concentration of Fe2+ in the plating solution causes an imbalance in the NiFe alloy composition, an increase in the nickel content causes an increase in coefficient of thermal expansion (CTE).
Furthermore, iron oxide which is an insoluble material in the plating solution, acts as impurities in the plating solution, causing protrusions on the surface of a plated material, and degrading the electroforming properties of the invar plating layer or causing stains on the surface.
Accordingly, the present invention has been made in view of the above-mentioned problems occurring in the related art, and it is an objective of the present invention to provide an electroplating apparatus and an electroplating method, which can plate a target on one side of a substrate while moving an anode horizontally.
Specifically, it is another objective of the present invention to provide an electroplating apparatus and an electroplating method, which can consistently maintain the concentration of iron ions in a plating solution through the injection of inert gas when the plating solution is supplied during the plating process.
To accomplish the above-mentioned objects, according to the present invention, there is provided an electroplating apparatus including: a tank unit having an open top and an internal accommodation space; an electroplating unit installed in the tank unit to plate a target object arranged inside the tank unit depending on power supplied from a power supply unit; a plating solution supply unit supplying plating solution to the electroplating unit and circulating the plating solution by receiving the plating solution from the tank unit; and a gas supply unit supplying inert gas to the electroplating unit, wherein the electroplating unit sprays the supplied plating solution and inert gas onto the target object.
Preferably, the electroplating unit includes: an anode part electrically connected to a positive electrode of the power supply unit and emitting ions toward the target object in the tank unit; a cathode part electrically connected to a negative electrode of the power supply unit and supporting the target object within the tank unit; and a first supply nozzle and a second supply nozzle respectively installed on one side and the other side of the anode part, and spraying the plating solution and inert gas together toward the target object.
Preferably, the first supply nozzle and the second supply nozzle are formed such that spray holes of the first supply nozzle and the second supply nozzle are inclined downward toward the underside of the anode part.
Preferably, the first supply nozzle and the second supply nozzle include a main supply pipe, and a first branch supply pipe and a second branch supply pipe branching from the main supply pipe, such that the plating solution and the inert gas supplied to the main supply pipe are selectively supplied to the first supply nozzle and the second supply nozzle via the first branch supply pipe and the second branch supply pipe.
Preferably, the inert gas is compressed nitrogen.
Preferably, the compressed nitrogen is sprayed at a speed sufficient to maintain a supersaturated state in the plating solution to block oxygen inflow.
Preferably, the compressed nitrogen is supplied at a rate of 0.1 l to 1.0 l per minute based on 100 l of plating solution.
In another aspect of the present invention, there is provided an electroplating method for plating a target object in a tank unit using an electroplating unit positioned above the tank unit, including: spraying plating solution and inert gas onto the target object through a supply nozzle of the electroplating unit.
Preferably, the inert gas is compressed nitrogen.
Preferably, the compressed nitrogen is sprayed at a speed sufficient to maintain a supersaturated state in the plating solution to block oxygen inflow.
Preferably, the compressed nitrogen is supplied at a rate of 0.1 l to 1.0 l per minute based on 100 l of plating solution.
The electroplating apparatus and the electroplating method according to embodiments of the present invention can plate a target on one side of the substrate while moving the anode horizontally, and consistently maintain the concentration of iron ions in a plating solution through the injection of inert gas when the plating solution is supplied during the plating process, thereby providing excellent plating quality.
Additionally, the electroplating apparatus and the electroplating method can prevent the generation of iron oxide in the plating solution and suppress the increase in the coefficient of thermal expansion, allow the cyclic reuse of the plating solution and the electrolyte, and provide different sizes of the plurality of anodes or change the number of channels to reduce the plating deviation.
The present invention can be modified in various forms and can have various embodiments. Specific embodiments will be illustrated in the drawings and described in detail. However, the embodiments are not intended to limit the present invention, but it should be understood that the present invention includes all modifications, equivalents, and replacements belonging to the concept and the technical scope of the present invention. In drawings, similar reference numerals are used for similar components.
It will be understood that terms, such as “first”, “second”, “A”, “B”, etc. may be used in the specification to describe various components but are not restricted to the above terms. The terms may be used to discriminate one component from another component. For instance, the first component may be named as the second component, and on the contrary, the second component may be also named as the first component within the scope of the present invention. The term “and/or” refers to a combination of multiple items associated and listed or any one of the associated and listed items.
It will be understood that when a component is referred to as being “coupled” or “connected” to another component, it can be directly coupled or connected to the other component or intervening components may be present therebetween. In contrast, it should be understood that when a component is referred to as being “directly coupled” or “directly connected” to another component, there are no intervening components present. Other expressions that explain the relationship between components, such as “between,” “directly between,” “adjacent to,” or “directly adjacent to,” should be construed in the same way.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise”, “include”, “have”, etc. when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or combinations of them but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or combinations thereof.
Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Hereinafter, the present disclosure will be described in more detail with reference to the exemplary embodiments.
Referring to
The tank unit 600 is formed to have the internal accommodation space to accommodate the plating solution inside. The tank unit 600 has an open top to allow the target object I to be inserted and removed in a horizontal direction, and a height to accommodate the entire target object I.
The plating solution is an electrolyte and can be a plating material to be used as a mask. In one embodiment, when invar thin plates, which are iron-nickel alloys, are manufactured as plating layers, a mixture where a solution containing Ni ions and a solution containing Fe ions are mixed can be used as the plating solution. In another embodiment, when super invar thin plates, which are an iron-nickel-cobalt alloy, are manufactured as plating layers, a mixture where a solution containing Ni ions, a solution containing Fe ions, and a solution containing Co ions are mixed can be used as the plating solution. In manufacturing organic light-emitting diodes (OLEDs), the invar thin plates or the super invar thin plates can be used as fine metal masks (FMMs) or shadow masks and can serve to accurately guide electron beams to the phosphor. Furthermore, the invar thin plates or the super invar thin plates, which have very low coefficient of thermal expansion (CTE), are less likely to experience deformation of a pattern shape of the masks caused by thermal energy, so are mainly used for manufacturing high-resolution OLEDs. Additionally, the invar thin plates or the super invar thin plates allow the use of any desired plating solution for the target plating layer without limitation. In this specification, manufacturing invar thin plates will be described as a primary example.
The plating solution supply unit 200 can supply the plating solution to the electroplating unit 100.
The plating solution supply unit 200 is configured to have a storage space for storing the plating solution. The plating solution supply unit 200 can receive and store the plating solution from an external plating solution supply source and supply the stored solution to a first supply nozzle 160 and a second supply nozzle 170 of the electroplating unit 100 through a supply pump (not illustrated). Furthermore, the plating solution supply unit 200 is connected to the tank unit 600 to receive and store the plating solution stored in the tank unit 600.
Consequently, the plating solution supplied to the first supply nozzle 160 and the second supply nozzle 170 of the electroplating unit 100 via the plating solution supply unit 200 is sprayed onto a target object I. The plating solution which flows downward due to gravity after passing through the target object I is stored in the tank unit 600, and is then recovered to the plating solution supply unit 200 connected to the tank unit 600, thus facilitating the overall circulation of the plating solution. The reason the plating solution supply unit 200 can circulate the plating solution is that inert gas is introduced along with the plating solution via the gas supply unit 400 when the plating solution is supplied to consistently maintain the concentration of iron ions in the plating solution, thereby suppressing the formation of iron oxide in the plating solution.
In this instance, the plating solution supply unit 200 may additionally include filters or other components to remove impurities from the plating solution.
The electrolyte supply unit 300 can supply the electrolyte solution to the electroplating unit 100.
The electrolyte supply unit 300 is configured to have a storage space for storing the electrolyte solution. The electrolyte supply unit 300 can receive and store the electrolyte solution from an external electrolyte solution supply source and supply the electrolyte solution stored in the storage space to the electroplating unit 100 through the supply pump (not illustrated). Additionally, the electrolyte supply unit 300 is connected to the electroplating unit 100 to receive and store the electrolyte solution from the electroplating unit 100.
Consequently, the electrolyte solution supplied to the electroplating unit 100 via the electrolyte supply unit 300 is recovered to the electrolyte supply unit 300 connected to the electroplating unit 100, thereby facilitating the overall circulation of the electrolyte solution.
The gas supply unit 400 can supply inert gas to the electroplating unit 100.
The gas supply unit 400 is configured to have a storage space which can store inert gas inside. The gas supply unit 400 can receive and store inert gas from an external inert gas supply source, and supply the inert gas stored in the storage space to the first supply nozzle 160 and the second supply nozzle 170 of the electroplating unit 100 through the supply pump (not illustrated).
Ultimately, the inert gas supplied to the first supply nozzle 160 and the second supply nozzle 170 of the electroplating unit 100 through the gas supply unit 400 is sprayed into the plating solution of the tank unit 600 along with the supplied plating solution. During the above-mentioned process, the inert gas maintains a supersaturated gas state in the plating solution suppressing oxygen inflow into the plating solution, thereby consistently maintaining the concentration of iron ions in the plating solution and suppressing the formation of iron oxide in the plating solution.
The power supply unit 500 can supply current to the electroplating unit 100. The power supply unit 500 can form a plurality of channels, with at least four or more channels. Moreover, each of the plurality of channels of the power supply unit 500 can control current values individually. Thus, the power supply unit 500 can adjust the size of the anodes or increase the number of channels to reduce plating deviations in the electroplating unit 100.
The electroplating unit 100 can form a plating layer (invar alloy) on one surface of the master for fine metal masks.
The electroplating unit 100 can be placed in an upper portion of the tank unit 600 and move horizontally along the tank unit 600. The electroplating unit 100 is electrically connected to the power supply unit 500 to receive current. Additionally, the electroplating unit 100 is connected to the plating solution supply unit 200 and the gas supply unit 400 to receive plating solution and inert gas, and is connected to the electrolyte supply unit 300 to receive electrolyte solution.
Referring to
Here, the anode part 110 and the first supply nozzle 160 and the second supply nozzle 170 respectively installed on one side and the other side of the anode part 110 move horizontally in conjunction with the anode part 110 under the external horizontal movement control.
A plurality of anodes of the anode part 110 can be electrically connected to the positive electrode of the power supply unit 500. The anode part 110 may have the plurality of anodes, preferably four or more, each of which can be individually controlled. Here, the anodes may be insoluble anodes.
The anodes of the anode part 110 can be arranged within a case, where the interior of the case is connected to the electrolyte supply unit 300 in a communicating manner to receive and store the electrolyte solution from the electrolyte supply unit 300 and circulate the electrolyte solution back to the electrolyte supply unit 300.
Additionally, the first supply nozzle 160 and the second supply nozzle 170 installed on both sides of the anode part 110 spray plating solution and inert gas toward the target object I located below. The first supply nozzle 160 and the second supply nozzle 170 can operate together to simultaneously spray the plating solution and the inert gas or operate independently to selectively spray the plating solution and the inert gas.
For the spraying of the plating solution and the inert gas from the first supply nozzle 160 and the second supply nozzle 170, the first supply nozzle 160 and the second supply nozzle 170 include a main supply pipe 130, and a first branch supply pipe 140 and a second branch supply pipe 150 branching from the main supply pipe 130.
A plating solution inlet 190 and a gas inlet 180 are connected to an upper portion of the main supply pipe 130. The plating solution inlet 190 is connected to the plating solution supply unit 200 to supply plating solution to the main supply pipe 130. Furthermore, the gas inlet 180 is connected to the gas supply unit 400 to supply the inert gas to the main supply pipe 130. Therefore, the plating solution and inert gas move together within the main supply pipe 130.
In this instance, reference numeral 181 designates a solenoid-type gas valve, which is provided to control the supply and the supply amount of inert gas from the gas supply unit 400 to the main supply pipe 130.
A lower portion of the main supply pipe 130 branches into the first branch supply pipe 140 and the second branch supply pipe 150. Within the first and second branch supply pipes 140 and 150, the plating solution and the inert gas move together, and the supply and the supply amount of the plating solution and the inert gas through the respective branch supply pipes are controlled depending on the operation of the first branch valve 141 and the second branch valve 151 installed in each pipe.
Here, the first branch supply pipe 140 is connected to the first supply nozzle 160 to supply the plating solution and the inert gas, and the second branch supply pipe 150 is connected to the second supply nozzle 170 to supply the plating solution and the inert gas.
The first supply nozzle 160 is installed on one side of the anode part 110, and a spray hole of the first supply nozzle 160 is inclined downward toward the lower portion of the anode part 110.
In addition, the second supply nozzle 170 is installed on the other side of the anode part 110, and a spray hole of the second supply nozzle 170 is also inclined downward toward the lower portion of the anode part 110.
The first supply nozzle 160 and second supply nozzle 170 can independently adjust whether to spray and the spray amount of the plating solution and the inert gas by the first branch valve 141 and the second branch valve 151.
Here, the main supply pipe 130, the branch supply pipes 140 and 150, and the supply nozzles 160 and 170 may be integrally formed.
The main supply pipe 130, the branch supply pipes 140 and 150, and the supply nozzles 160 and 170 of the electroplating unit 100, which are integrally formed, can move horizontally and vertically via a driving mechanism (not illustrated). During the horizontal movement, the integrated main supply pipe 130, branch supply pipes 140 and 150, and supply nozzles 160 and 170, which are coupled at the lower part move in one direction or in the opposite direction relative to the target object I while maintaining a horizontal orientation. Moreover, during vertical movement, the integrated main supply pipe 130, branch supply pipes 140 and 150, and supply nozzles 160 and 170 move up and down.
Referring to
In conventional plating systems, vortices generated during the spraying of the plating solution caused plating stains on the plating layer. Additionally, the conventional plating systems worsened the degree of stains in proportion to the spray flow rate of the plating solution. In addition, when the flow rate of the sprayed plating solution is reduced to reduce stains on the plated surface, the conventional plating systems caused dent defects on the plated surface due to slow degassing of hydrogen gas.
The first branch valve 141 and the second branch valve 151 are respectively installed to the plating solution spray nozzles to selectively operate the first supply nozzle 160 and the second supply nozzle 170 in the movement direction of the insoluble anode, thereby eliminating the factors that cause vortices during the spray of the plating solution. Additionally, since the first supply nozzle 160 and the second supply nozzle 170 can independently adjust whether to spray and the spray flow rate, when the spray flow rate in the movement direction of the anode part 110 is increased, hydrogen gas generated on the cathode surface can be degassed rapidly, thus preventing dent defects on the plated surface. Furthermore, the first supply nozzle 160 and the second supply nozzle 170 according to an embodiment of the present invention are formed to be inclined downward toward the lower portion of the anode part 110, minimizing dent and stains formed on the plated surface.
In addition, the cathode parts 120 can be electrically connected to the negative electrodes of the power supply unit 500. The cathode parts 120 can be respectively positioned at both lateral edges of the tank unit 600. The cathode part 120 may include clamps 121 at the ends of both sides of the tank unit 600. The clamps 121 are in contact with the target object I, and grip and support the both lateral edges of the target object I. The clamps 121 can fix the target object I to prevent the horizontal movement of the target object I. The clamps 121, which is formed from conductive material, connect the cathode part 120 and the target object I, thus serving as a medium allowing current applied to the cathode part 120 to flow through the target object I and the anode part 110.
Meanwhile, when an invar thin plate, which is an iron-nickel alloy, is manufactured as a plating layer, the plating solution used as the material for the plating layer can allow the large/small area of an object to be plated, plating thickness variations between a via or thru hole and the ground, and an aspect ratio to be determined by additives introduced in amounts ranging from a few milliliters to several tens of milliliters.
The additives may be accelerators and brighteners, which are organic compounds, such as SPS, MPSA, DPS, and thiourea, suppressors and carriers, which are polymeric organic substances, such as PEG, gelatin, and collagen, and polymeric organic substances and levelers, such as Janus Green B (JGB), PEI, and HEC. Among them, sulfur compounds serving as accelerators can be easily decomposed by oxygen generated at the anode part 110 during plating.
Here, the priority qualification for invar materials used for fine metal masks FMMs is a low coefficient of thermal expansion (CTE). To obtain invar having low CTE through electroplating, a composition ratio of Ni2+ and Fe2+ in the plating solution is very important.
Therefore, the invar plating solution must precipitate Ni—Fe alloys onto the substrate at a consistent ratio, with a nickel content of 36% to 38%. To maintain the precipitation ratio, the concentrations of Ni salts (Ni2+) and Fe salts (Fe2+) in the plating solution must be kept stable.
However, iron oxide (4Fe3++3O2→2Fe2O3) can be produced by oxygen (O2) generated from the reaction at the insoluble anode (H2O→½O2+2H++2e−) and Fe3+ generated from the spontaneous reaction of Fe2+ (Fe2+→Fe3++e−).
The oxygen produced at the anode part 110 during plating promotes the unstable oxidation of Fe2+, rapidly decreasing the Fe2+ concentration in the plating solution. Furthermore, the iron oxide generated through the above may decrease the reduction of Fe3+ back to iron ions by the reduction reaction of Fe3+ (Fe3++e−>Fe2+). Additionally, when the Fe2+ concentration decreases significantly compared to the Ni2+ concentration, the Ni composition ratio in the alloy precipitated on the cathode increases relatively, making it impossible to obtain an invar material with a low coefficient of thermal expansion.
As illustrated in
To suppress iron oxide formation caused by oxygen generated at the anode part 110, one conventional technique attempted to install an ion exchange membrane, which allows the passage of ions emitted from the anode and blocks the movement of the plating solution and the electrolyte solution, at the anode part 110. The ion exchange membrane could block the oxygen entry pathway from the insoluble anode, but could not address the oxygen entry pathway caused by the contact between air and the plating solution.
In the present invention, as described above, to control two supply pathways of dissolved oxygen in the plating solution, the first supply nozzle 160 and the second supply nozzle 170 supply the plating solution and the inert gas together.
In this instance, the inert gas is preferably nitrogen (N2) gas, but other chemically stable and low-reactivity inert gases can also be used. Specifically, when the inert gas is nitrogen, compressed nitrogen gas with purity of 99.99% or higher and pressure of 120 kg/cm2 can be used.
The inert gas, when sprayed into the plating solution, facilitates the degassing of hydrogen gas attached to the surface of the cathode part 120 and maintains a nitrogen supersaturation state in the plating solution, thereby preventing iron oxide formation by controlling the introduction of oxygen generated at the insoluble anode and the introduction of oxygen from the atmosphere.
Dissolved oxygen (DO) is molecular oxygen dissolved in water or solution, generally supplied by oxygen in the air. The amount of dissolved oxygen in water or solution is influenced by temperature and pressure. Moreover, as the temperature of the solution increases, the dissolved oxygen content decreases.
In the usage conditions of the plating solution in the electroplating apparatus according to the present invention, the dissolved oxygen supply pathways in the plating solution are formed by two cases: contact between air and plating solution; and introduction of oxygen generated from the insoluble anode reaction. In the present invention, the first supply nozzle 160 and the second supply nozzle 170 continuously supply inert gas to the plating solution, preventing the additional influx of oxygen into the plating solution.
According to the number of plating cycles (zero to ten times), the Fe2+ concentrations in plating solution for a case where inert gas (N2) was not injected to the plating solution, a case where 0.1 l/min of N2 was injected to the plating solution, and a case where 1.0 l/min of N2 was injected to the plating solution are shown in the following Table 1.
Here, the supply amount of inert gas (N2) was measured based on 100 L of invar plating solution.
Referring to
According to the number of plating cycles (zero to ten times), the Ni contents in invar for a case where inert gas (N2) was not injected to the plating solution, a case where 0.1 L/min of N2 was injected to the plating solution, and a case where 1.0 L/min of N2 was injected to the plating solution are shown in the following Table 2.
Referring to
According to the number of plating cycles (zero to ten times), the dissolved oxygen contents (mg/l) in plating solution for a case where inert gas (N2) was not injected to the plating solution, a case where 0.1 l/min of N2 was injected to the plating solution, and a case where 1.0 l/min of N2 was injected to the plating solution are shown in the following Table 3.
Here, the supply amount of inert gas (N2) was measured based on 100 l of invar plating solution. Additionally, dissolved oxygen measurements were performed using the METTLER TOLEDO InPro6860i/12/120/nA sensor at 40° C.
Referring to
As described above, the optimal embodiments has been disclosed in the drawings and the specification. Specific terms have been used herein for descriptive purposes, not for purposes of limitation of meanings or to limit the scope of the invention as set forth in the claims. Therefore, it would be understood by those skilled in the art that various modifications and equivalent embodiments are possible from the present disclosure. Accordingly, the true scope of protection of the present disclosure should be determined by the technical concept of the attached claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202311537740.4 | Nov 2023 | CN | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2023/137032 | Nov 2023 | WO |
| Child | 19176981 | US |
