Silicon wafer texturing liquid level control device
By adopting a design that connects the secondary tank and the reaction tank in the silicon wafer texturing process, and using a liquid level control switch and controller to achieve precise liquid drainage, the problem of unstable liquid level is solved, costs are reduced and the texturing effect is improved.
Patent Information
- Application Number
- CN202422315737.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-09-23
AI Technical Summary
In the existing technology, the liquid level in the reaction tank is unstable during the silicon wafer texturing process, resulting in large liquid level detection errors, which affects the texturing effect. In addition, the drainage device is complex and costly.
The design connects the secondary tank to the reaction tank. The liquid level is detected by a liquid level control switch in the secondary tank, and the drain valve is triggered to open at a preset height. Combined with the controller, precise draining is achieved, reducing the reliance on additional draining devices.
It enables precise liquid drainage during the silicon wafer texturing process, reduces drainage costs, and improves the accuracy of liquid level detection and texturing effect.
Smart Images
Figure CN223535294U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of photovoltaic technology, and in particular to a silicon wafer texturing liquid level control device. Background Technology
[0002] During the texturing process of silicon wafers, the reactants in the reaction solution are consumed, requiring continuous replenishment of the reaction solution. In addition, the texturing reaction produces byproducts, causing the liquid level in the reaction tank to rise continuously, which may affect the texturing effect of silicon wafers. Therefore, in order to control the reaction solution in the reaction tank within a certain liquid level range, a special drainage device is required to achieve precise drainage, such as a device that can accurately measure the replenished solution and the volume of drainage. This device is not only complex to install and set up, but also has a high drainage cost. Utility Model Content
[0003] This application discloses a silicon wafer texturing liquid level control device, which can achieve precise liquid drainage during the silicon wafer texturing process and reduce drainage costs.
[0004] This application discloses a silicon wafer texturing liquid level control device, comprising:
[0005] A reaction tank, configured to hold a reaction solution;
[0006] A secondary tank, which is connected to the reaction tank, is used to hold the reaction solution together with the reaction tank;
[0007] A drain valve is provided in the reaction tank and / or the auxiliary tank;
[0008] A liquid level control switch is installed in the secondary tank to detect the liquid level of the reaction solution and trigger the opening of the drain valve when the liquid level of the reaction solution reaches a preset height.
[0009] In one embodiment, the secondary tank is provided with a drain port, the drain port is connected to a drain pipe, and the drain valve is provided on the drain pipe.
[0010] In one embodiment, the drain valve includes a pneumatic diaphragm valve.
[0011] In one embodiment, the volume of the secondary tank is smaller than the volume of the reaction tank.
[0012] In one embodiment, the silicon wafer texturing liquid level control device further includes a controller, which is connected to the liquid level control switch and the drain valve;
[0013] The controller is used to receive the control signal generated by the liquid level control switch when the liquid level of the reaction solution reaches a preset height, and to control the opening of the drain valve according to the control signal.
[0014] In one embodiment, the liquid level control switch includes a float switch, which includes a float, a fixed rod, and a magnetic switch. The float is movably disposed on the fixed rod and has a magnetic component. The magnetic switch is connected to the controller and is used to close under the magnetic field of the magnetic component when the liquid level of the reaction solution reaches the preset height, so as to transmit a control signal to the controller.
[0015] In one embodiment, the float includes a hollow portion, and the float is movably disposed on the fixed rod through the hollow portion.
[0016] In one embodiment, the magnetic element is a ring-shaped magnetic element.
[0017] In one embodiment, the controller is further configured to control the drain valve to open according to the control signal if the current time period is a preset time period.
[0018] In one embodiment, the controller includes a programmable logic controller (PLC).
[0019] In this embodiment, the silicon wafer texturing liquid level control device may include a tank, a drain valve, and a liquid level control switch. The connection between the secondary tank and the reaction tank within the tank effectively buffers fluctuations in the reaction solution during the silicon wafer texturing process. This ensures that the liquid level control switch in the secondary tank can accurately detect the liquid level of the reaction solution. When the preset height is reached, the drain valve is triggered to open, discharging the reaction solution held in both the reaction tank and the secondary tank. This achieves precise drainage during the silicon wafer texturing process, thereby accurately managing the liquid level of the reaction solution and preventing a reduction in the texturing effect due to excessive reaction solution. Furthermore, it reduces the reliance of the silicon wafer texturing liquid level control device on additional drain devices, effectively lowering drainage costs. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] Figure 1-A This is a schematic diagram of the structure of a silicon wafer texturing liquid level control device disclosed in an embodiment of this application;
[0022] Figure 1-B This is a schematic diagram of another silicon wafer texturing liquid level control device disclosed in the embodiments of this application;
[0023] Figure 2-A This is a schematic diagram of a float switch in a closed state as disclosed in an embodiment of this application;
[0024] Figure 2-B This is a schematic diagram of a float switch in the off state as disclosed in an embodiment of this application. Detailed Implementation
[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0026] It should be noted that the terms "comprising" and "having" and any variations thereof in the embodiments of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to these processes, methods, products, or devices.
[0027] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another.
[0028] This application discloses a silicon wafer texturing liquid level control device, which can achieve precise liquid drainage during the silicon wafer texturing process and reduce drainage costs.
[0029] The following will be described in detail with reference to the accompanying drawings.
[0030] In related technologies, silicon wafer texturing is a processing step in the fabrication of solar cells. Texturing creates a light-trapping structure on the surface of the silicon wafer, reducing reflectivity and improving the solar cell's utilization of sunlight. Currently, solar-grade crystalline silicon wafers include polycrystalline silicon and monocrystalline silicon. Polycrystalline silicon texturing uses an acidic etching solution, while monocrystalline silicon texturing uses an alkaline etching solution. The surface of the silicon wafer etched with the acidic solution has a wormhole-like texture, while the surface etched with the alkaline solution has a pyramidal texture. Both textured structures reduce the surface reflectivity of the silicon wafer, thus improving the solar cell's utilization of sunlight.
[0031] like Figure 1-A As shown, Figure 1-AThis is a schematic diagram of a silicon wafer texturing liquid level control device disclosed in an embodiment of this application. The silicon wafer texturing liquid level control device may include a tank (reaction tank 110 and auxiliary tank 120), a drain valve 130, and a liquid level control switch 140.
[0032] The reaction tank 110 is configured to hold the reaction solution;
[0033] The auxiliary tank 120 is connected to the reaction tank 110 so that they can hold the reaction solution together.
[0034] Drain valve 130 is installed in the tank body;
[0035] A liquid level control switch 140 is installed in the auxiliary tank 120. The liquid level control switch 140 is used to detect the liquid level of the reaction solution and trigger the drain valve 130 to open when the liquid level of the reaction solution reaches a preset height.
[0036] The reaction tank 110 is configured to hold the reaction solution and serves as the primary container for it. This reaction solution can refer to the solution required during the silicon wafer texturing process. Optionally, the reaction solution can be an alkaline solution, which may contain components such as potassium hydroxide and sodium hydroxide. The silicon wafer texturing process refers to the chemical etching of the silicon wafer surface to form the desired textured surface structure. It is understood that the reaction tank 110 can be made of a corrosion-resistant material, such as an alkali-resistant material, to ensure long-term use in highly corrosive environments. Alternatively, the reaction solution can also be an acidic solution, such as nitric acid or nitrous acid; there are no limitations on this.
[0037] Optionally, the capacity and shape of the reaction cell 110 can be determined according to the process requirements of silicon wafer texturing. Figure 1-A The intermediate reaction tank 110 is rectangular in shape, which is only an example and is not limited in this application embodiment.
[0038] In the silicon wafer texturing process, taking an alkaline reaction solution as an example, the reactant in the texturing reaction is the alkali in the reaction solution, and the byproducts include silicates, such as potassium silicate or sodium silicate. To maintain the reactivity of the reaction solution, the concentrations of alkali and silicates in the reaction tank 110 need to be controlled within a certain range. Therefore, to ensure the effectiveness of silicon wafer texturing, it is necessary to add reaction solution to the reaction tank 110 and remove the generated byproducts. Consequently, related technologies often use the detection of the reaction solution level to determine the timing of drainage.
[0039] However, the texturing process of silicon wafers in the reaction tank 110 may cause unstable fluctuations in the liquid level of the reaction solution in the reaction tank 110, such as bubbles and disturbances of reaction products. Therefore, liquid level detection in the reaction tank 110 may lead to errors, which in turn affect the accuracy of liquid level control.
[0040] To address this issue, this application introduces a secondary tank 120, which can be connected to the reaction tank 110 to share the reaction solution, ensuring consistent liquid levels between the two tanks. However, since no chemical reaction occurs in the secondary tank 120, its liquid level is more stable than that of the reaction tank 110. Therefore, a level control switch 140 can be installed in the secondary tank 110 for level detection, preventing interference from level fluctuations in the reaction tank 120 and improving the accuracy of level detection.
[0041] Optionally, this application embodiment does not limit the connection channel between the sub-tank 120 and the reaction tank 110, and the connection channel can be of any form.
[0042] like Figure 1-A As shown, the tank is provided with a partition 150, which divides the tank into a reaction tank 110 and a sub-tank 120. The partition 150 is provided with an opening 151, which is configured to connect the sub-tank 120 with the reaction tank 110. That is, the connecting channel can be the opening between the sub-tank 120 and the reaction tank 110, and the reaction solution flows between the reaction tank 110 and the sub-tank 120 through the opening.
[0043] Or, such as Figure 1-B As shown, Figure 1-B This is a schematic diagram of another silicon wafer texturing liquid level control device disclosed in the embodiments of this application, wherein the secondary tank 120 and the reaction tank 120 are arranged at intervals, and the secondary tank 120 is connected to the reaction tank 110 through a connecting pipe 160. That is, the connecting channel can be the connecting pipe 160 between the secondary tank 120 and the reaction tank 110, and the reaction solution flows between the reaction tank 110 and the secondary tank 120 through the pipe.
[0044] The height of the connecting channel in the reaction tank 110 can be lower than the liquid level range required during the silicon wafer texturing process, so that the reaction solution can flow between the two to ensure consistent liquid levels. For example, if the liquid level needs to be in the range of 20 cm to 40 cm during the silicon wafer texturing process, the height of the connecting channel can be 5 cm, that is, the connecting channel is 5 cm away from the bottom of the reaction tank 110.
[0045] Optionally, the bottom of the sub-tank 120 and the bottom of the reaction tank 110 may be at the same level, but this is not the only limitation. The embodiments of this application only limit the arrangement of the sub-tank 120, the reaction tank 110 and the connecting channel to ensure that the liquid levels of the sub-tank 120 and the reaction tank 110 are consistent.
[0046] Understandably, in order to avoid too much reaction solution flowing into the secondary tank 120 and failing to react chemically with the silicon wafer, the volume of the secondary tank 120 can be smaller than that of the reaction tank 110, thereby improving the efficiency of the silicon wafer texturing reaction and avoiding waste of the reaction solution.
[0047] Optionally, the secondary tank 120 may be equipped with a drain port, which can be connected to a drain pipe, and a drain valve 130 may be installed in the drain pipe. The drain port may be located at the bottom of the secondary tank 120, and one end of the drain pipe may be connected to the drain port, while the other end may be connected to a waste liquid collection device or other waste liquid treatment device, thereby enabling the collection of the reaction waste liquid discharged from the secondary tank.
[0048] The drain valve 130 can be used to drain excess reaction solution when the liquid level of the reaction solution reaches a preset height. The drain valve 130 can be installed in the tank body; that is, the drain valve can be installed in the reaction tank and / or the auxiliary tank. Specifically, for example… Figure 1-A As shown, the drain valve 130 can be located below the auxiliary tank 120. The reaction solution in the treatment tank 120 can be discharged from the open drain valve 130 under the action of gravity. It should be understood that... Figure 1-A as well as Figure 1-B The drain valve 130 is located in the secondary tank, which is only one example.
[0049] The opening of the drain valve 130 can be triggered by the level control switch 140. When the liquid level of the reaction solution in the auxiliary tank 120 reaches the preset height, the level control switch 140 can trigger the drain valve 130 to open, discharging the excess reaction solution to the waste liquid collection device or other waste liquid treatment device.
[0050] Optionally, the drain valve may include a pneumatic diaphragm valve, a solenoid valve, a pulse valve, etc., and achieves quantitative draining each time it is opened. Specifically, the drain valve can drain a fixed amount of reaction solution to lower the liquid level of the reaction solution in reaction tank 110 and auxiliary tank 120 to a certain range. After the drain valve drains a fixed amount of reaction solution, it indicates that the liquid level of the reaction solution in reaction tank 110 and auxiliary tank 120 has reached a certain range, at which point the drain valve 130 can be closed.
[0051] The liquid level control switch 140 can be installed inside the secondary tank 120. It can detect the liquid level of the reaction solution in the secondary tank 120 and generate a control signal when the liquid level of the reaction solution reaches a preset height. This control signal is used to enable the drain valve 130 to open when the liquid level of the reaction solution reaches the preset height.
[0052] In one embodiment, the silicon wafer texturing liquid level control device may further include a controller, which can be connected to the liquid level control switch 140 and the drain valve 130. The controller is used to receive the control signal generated by the liquid level control switch 140 when the liquid level of the reaction solution reaches a preset height, and to control the drain valve 130 to open according to the control signal. By coordinating the operation of the liquid level control switch 140 and the drain valve 130 through the controller, more intelligent liquid level management and automated control can be achieved.
[0053] The controller can communicate with the liquid level control switch 140 and the drain valve 130. The liquid level control switch 140 can send a control signal to the controller. The controller can control the drain valve 130 to open according to the control signal, or generate an opening signal for the drain valve 130 according to the control signal, so that the drain valve 130 opens.
[0054] Since drainage cannot be performed at any time, the controller is also used to control the drainage valve 130 to open during a preset time period based on a controller signal. The controller can also determine whether the current period is within the preset time period, which can refer to a pre-defined time frame during which drainage is permitted. Upon receiving a control signal from the level control switch 140, if the current period is within the preset time period, the controller will control the drainage valve to open according to the control signal; otherwise, it will not respond to the control signal.
[0055] Optionally, the controller may include a PLC (Programmable Logic Controller). Alternatively, the controller may also include a central processing unit, a microprocessor, etc.
[0056] Optionally, the level control switch may include a float switch, which uses the up-and-down movement of a float to determine the level of the reaction solution. When the level of the reaction solution reaches a preset height, the float switch can close to trigger the opening of the drain valve. Understandably, when the level control switch is closed, the controller can receive a control signal. Alternatively, the level control switch may also include a magnetic telescopic switch or a capacitive control switch, but compared to other level control switches, the float switch is less prone to jamming, more stable and reliable, and offers better cost-effectiveness.
[0057] Optionally, the liquid level control switch can also be set to output a liquid replenishment signal when the liquid level reaches the target height, so that the controller controls the liquid replenishment device to replenish the reaction solution to the reaction tank 110 to ensure that the silicon wafer texturing process proceeds normally. The target height can be less than the preset height or less than the liquid level range required in the silicon wafer texturing process.
[0058] To explain the working principle of a float switch more clearly, such as Figure 2-A and Figure 2-B As shown, Figure 2-A This is a schematic diagram of a float switch in the closed state as disclosed in an embodiment of this application. Figure 2-B This is a schematic diagram of a float switch in the off state according to an embodiment of this application. The float switch may include a float 210, a fixing rod 220, and a magnetic switch 230. The float 210 may be provided with a magnetic element 211.
[0059] The float 210 is fitted onto the fixed rod 220 through a hollow portion, allowing it to move relative to the fixed rod 220. This application does not limit the shape of the float 210. When the liquid level of the reaction solution reaches a preset height, the float 210 can be positioned at... Figure 2-A As shown, when float 210 is close to magnetic switch 230, magnetic component 211 is also close to magnetic switch 230. Under the influence of the magnetic field of magnetic component 211, magnetic switch 230 closes, thereby transmitting a control signal to the controller. When the liquid level of the reaction solution has not reached the preset height, float 210 can be positioned at... Figure 2-A As shown, when the float 210 is far away from the magnetic switch 230, the magnetic component 211 is also far away from the magnetic switch 230. The magnetic field of the magnetic component 211 cannot affect the magnetic switch 230, so the magnetic switch 230 can be disconnected, meaning it will not transmit control signals to the controller.
[0060] Optionally, the float switch may also include a height limiting element to prevent the float from being close to the magnetic switch 230 when the liquid level of the reaction solution is higher than a preset height. In both the closed and open states of the magnetic switch 230, the float switch can output two different control signals to open and close the drain valve 130. Specifically, if the liquid level of the reaction solution is higher than the preset height, the magnetic switch 230 is closed, and the control signal output by the float switch indicates that drainage should begin; the controller can then control the drain valve to open. If the liquid level of the reaction solution is not higher than the preset height, the magnetic switch 230 is open, and the control signal output by the float switch indicates that drainage should stop; the controller can then control the drain valve to close.
[0061] Optionally, in order to make the magnetic field effect more balanced, the magnetic component 211 can be a toroidal magnetic component.
[0062] In this embodiment, the silicon wafer texturing liquid level control device may include a tank, a drain valve, and a liquid level control switch. The connection between the secondary tank and the reaction tank within the tank effectively buffers fluctuations in the reaction solution during the silicon wafer texturing process. This ensures that the liquid level control switch in the secondary tank can accurately detect the liquid level of the reaction solution. When the preset height is reached, the drain valve is triggered to open, discharging the reaction solution held in both the reaction tank and the secondary tank. This achieves precise drainage during the silicon wafer texturing process, thereby accurately managing the liquid level of the reaction solution and preventing a reduction in the texturing effect due to excessive reaction solution. Furthermore, it reduces the reliance of the silicon wafer texturing liquid level control device on additional drain devices, effectively lowering drainage costs.
[0063] In the description of this specification, references to terms such as "some embodiments," "other embodiments," and "ideal embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.
[0064] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0065] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.
Claims
1. A silicon wafer texturing liquid level control device, characterized in that, include: The tank includes a reaction tank and a sub-tank. The reaction tank is configured to hold a reaction solution, and the sub-tank is connected to the reaction tank so as to hold the reaction solution together with the reaction tank. A drain valve is installed in the tank. A liquid level control switch is installed in the secondary tank. The liquid level control switch is used to detect the liquid level of the reaction solution and trigger the opening of the drain valve when the liquid level of the reaction solution reaches a preset height.
2. The silicon wafer texturing liquid level control device according to claim 1, characterized in that, The secondary tank is provided with a drain port, which is connected to a drain pipe, and the drain valve is located on the drain pipe.
3. The silicon wafer texturing liquid level control device according to claim 1, characterized in that, The drain valve includes a pneumatic diaphragm valve.
4. The silicon wafer texturing liquid level control device according to claim 1, characterized in that, The volume of the secondary tank is smaller than the volume of the reaction tank.
5. The silicon wafer texturing liquid level control device according to claim 4, characterized in that, The tank is equipped with a partition that divides the tank into a reaction tank and a secondary tank. The partition has an opening configured to allow communication between the secondary tank and the reaction tank. The secondary tank is spaced apart from the reaction tank, and the secondary tank is connected to the reaction tank through a connecting pipe.
6. The silicon wafer texturing liquid level control device according to claim 1, characterized in that, The silicon wafer texturing liquid level control device further includes a controller, which is connected to the liquid level control switch and the drain valve; The controller is used to receive the control signal generated by the liquid level control switch when the liquid level of the reaction solution reaches a preset height, and to control the opening of the drain valve according to the control signal.
7. The silicon wafer texturing liquid level control device according to claim 6, characterized in that, The liquid level control switch includes a float switch, which includes a float, a fixed rod, and a magnetic switch. The float is movably disposed on the fixed rod and has a magnetic component. The magnetic switch is connected to the controller and is used to close under the magnetic field of the magnetic component when the liquid level of the reaction solution reaches the preset height, so as to transmit a control signal to the controller.
8. The silicon wafer texturing liquid level control device according to claim 7, characterized in that, The float includes a hollow portion, and the float is sleeved on the fixed rod through the hollow portion so that it is movable relative to the fixed rod.
9. The silicon wafer texturing liquid level control device according to claim 6, characterized in that, The controller is also used to control the drain valve to open according to the control signal during a preset time period.
10. The silicon wafer texturing liquid level control device according to any one of claims 6 to 9, characterized in that, The controller includes a programmable logic controller.