Cleaning system

Abstract

This invention discloses a cleaning system, comprising: two sets of cleaning equipment arranged back-to-back; a solution preparation system for supplying and proportioning the required chemical solution to the treatment tank; a drainage system shared by both sets of cleaning equipment; a water supply system shared by both sets of cleaning equipment; and a control system including a solution replacement control device and a drainage control device. The solution replacement control device controls the solution preparation system to supply and proportion the required chemical solution to the treatment tank, and calculates the remaining number of treatment cycles for each treatment tank based on the relationship between the chemical solution volume and the weight of the silicon wafer. When the remaining number of treatment cycles for a treatment tank is less than 1, a drainage signal is sent to the drainage control device. The drainage control device then controls the valve of the drainage branch pipe connected to the corresponding treatment tank in the drainage system to drain the solution. Finally, the solution replacement control device replaces the solution in the corresponding treatment tank. This invention can save costs and improve the automation level of the cleaning system.

Description

Technical Field

[0001] This invention relates to the technical field of cleaning equipment for solar cell production, and more particularly to a cleaning system that automatically processes cleaning solutions for cleaning equipment. Background Technology

[0002] With the increasing global demand for renewable energy, the solar photovoltaic industry has developed rapidly. In the manufacturing process of solar cells, silicon wafers need to undergo processes such as cleaning (wet processing), diffusion, annealing, coating, and screen printing. Currently, the most common cleaning equipment is the tank-type equipment and the chain-type equipment. The tank-type equipment uses baskets to carry the silicon wafers, with robotic arms carrying the baskets and immersing them in various processing tanks for cleaning. Different solutions are prepared in each processing tank to facilitate the corresponding wet processing of the silicon wafers.

[0003] However, existing cleaning equipment is all independent units. For example, a cleaning system needs to be equipped with a corresponding solution preparation system, drainage system, water supply system, etc. This results in each cleaning system occupying a large space and having a high cost.

[0004] In addition, existing cleaning equipment requires the use of acidic and / or alkaline solutions such as HCl, H2O2, NaOH, and KOH. However, the replacement and drainage of solutions in existing cleaning equipment require intervention from process personnel. This intervention not only poses risks of personnel coming into contact with chemicals and exposure, but also leads to long solution preparation times, thereby affecting equipment capacity.

[0005] Therefore, how to provide a low-cost and automatically controlled cleaning system is a technical problem to be solved. Summary of the Invention

[0006] To address the technical problems of high cost and low automation in existing cleaning systems, this invention proposes a cleaning system.

[0007] The cleaning system proposed in this invention includes:

[0008] Two sets of cleaning equipment are set back to back. Each set of cleaning equipment includes at least one cleaning device. Each cleaning device includes multiple processing tanks arranged in sequence, a first weighing device set at the loading point for weighing the silicon wafers before processing, and a second weighing device set at the unloading point for weighing the silicon wafers after processing.

[0009] The solution preparation system delivers and proportions the required pharmaceutical solution to the treatment tank.

[0010] The drainage system is shared by two sets of cleaning equipment. The drainage system includes drainage branch pipes with first valves that are connected to the treatment tanks of each cleaning equipment in a one-to-one correspondence, and a drainage main pipe that is connected to the drainage branch pipes.

[0011] A water supply system shared by two sets of cleaning equipment provides cleaning water and chemical preparation water for the cleaning equipment.

[0012] The control system includes a liquid replacement control device and a liquid discharge control device. The liquid replacement control device controls the liquid preparation system to deliver and proportion the required chemical solution to the processing tank. Based on the relationship between the chemical solution volume and the weight of the silicon wafer, it calculates the remaining number of processing cycles for each processing tank. When the remaining number of processing cycles for a processing tank is less than 1, it sends a liquid discharge signal to the liquid discharge control device. The liquid discharge control device then controls the valve of the liquid discharge branch pipe connected to the corresponding processing tank in the liquid discharge system to discharge the liquid. After that, the liquid replacement control device replaces the liquid in the corresponding processing tank.

[0013] Furthermore, the remaining number of processing cycles in the processing tank is determined by formula [G] 总 -(G0+…+G i )] / G i+1 Calculations show that G 总 G0 is the total weight of silicon wafers that can be processed based on the solution volume of the first treatment tank at the top of the cleaning equipment before processing begins. G0 is the weight of silicon wafers processed in the first treatment tank at the top of the cleaning equipment after solution preparation. i It is the weight of the silicon wafer most recently processed after solution preparation, G i+1 This is the weight of the next batch of silicon wafers to be processed.

[0014] Furthermore, the drainage device controls each treatment tank in the same cleaning equipment to drain liquid sequentially from upstream to downstream, according to the position of the treatment tank in the cleaning equipment.

[0015] Furthermore, the cleaning equipment also includes a level gauge for detecting the liquid level in the treatment tank. The liquid replacement control device calculates the cleaning time and preparation time of each treatment tank based on the signal from the level gauge during the cleaning and dispensing process. The drain control device calculates the draining time based on the signal from the level gauge during the draining process.

[0016] Furthermore, each group of cleaning equipment includes one cleaning device. When two cleaning devices are started, the cleaning device with the relatively faster solution preparation time in the upstream treatment tank is given priority in solution preparation, and the solution is prepared within t... 排1 *β% of the time elapsed, the upstream treatment tank, where the solution preparation time is relatively slow, begins to prepare the cleaning equipment. 排1 The draining time of the upstream treatment tank of the cleaning equipment that prioritizes liquid preparation, 0 < β < 100.

[0017] Furthermore, the drainage system also includes a buffer branch pipe with a second valve connected to each of the treatment tanks, at least one buffer tank connected to the buffer branch pipe, and the drainage port of the buffer tank is connected to the main drainage pipe.

[0018] Furthermore, the drainage control device calculates the buffer time difference Δt = t_up of the next processing tank of the upstream processing tank for preparing the solution in the two cleaning devices. 排2 +t 配2 +t 洗2 -t 下游处理 -t 配1 -t 洗1 And when the buffer time difference is greater than γ, the treatment tank is controlled to drain through the buffer branch pipe, γ≥0, t 排2 t 洗2 and t 下游处理 The t represents the drainage time, cleaning time, and total processing time of the next processing tank after the upstream processing tank containing the solution to be prepared, respectively. 配1 and t 洗1 This refers to the solution preparation time and cleaning time for the upstream treatment tank containing the solution to be prepared within the same cleaning equipment.

[0019] Furthermore, the liquid replacement control device is set up one-to-one with the cleaning equipment. The liquid replacement control device is equipped with a one-button start / stop function. When the detection device detects an abnormality, the liquid replacement control device can pause or restart the liquid preparation function through the one-button start / stop function.

[0020] Furthermore, the solution includes an acidic solution and / or an alkaline solution.

[0021] This invention saves costs by setting up two sets of cleaning equipment back to back, allowing them to share a drainage system. Furthermore, by calculating the remaining number of cleaning cycles in the treatment tank and then controlling the timely drainage, cleaning, and liquid replacement of the corresponding treatment tank, this invention improves production efficiency. Attached Figure Description

[0022] The present invention will now be described in detail with reference to the embodiments and accompanying drawings, wherein:

[0023] Figure 1 This is a schematic diagram of the structural framework of an embodiment of the present invention.

[0024] Figure 2 This is a flowchart of a processing embodiment of the present invention. Detailed Implementation

[0025] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0026] Therefore, a feature pointed out in this specification is used to describe one feature of one embodiment of the invention, and does not imply that every embodiment of the invention must have the described feature. Furthermore, it should be noted that this specification describes many features. Although certain features may be combined to illustrate possible system designs, these features may also be used in other combinations not explicitly stated. Therefore, unless otherwise stated, the described combinations are not intended to be limiting.

[0027] The cleaning system of the present invention includes two sets of cleaning devices, which are arranged back to back. The front of the cleaning device refers to the side with a transparent observation window or an openable operating door, while the back of the cleaning device is the side opposite to the front.

[0028] Each cleaning unit comprises at least one cleaning device, and each cleaning device includes multiple processing tanks arranged in sequence, with the arrangement of the processing tanks perpendicular to the front or back of the cleaning device. Each cleaning device has a loading point and a unloading point. The loading point is equipped with a first weighing device for weighing the silicon wafers before processing, and the unloading point is equipped with a second weighing device for weighing the silicon wafers after processing.

[0029] In addition to cleaning equipment, a cleaning system also includes a liquid preparation system, a liquid drainage system, a water supply system, and a control system.

[0030] The solution preparation system delivers and proportions the required chemicals to the treatment tank. Two sets of cleaning equipment can share the same solution preparation system, but the control is relatively complex. It is better to configure one solution preparation system for each cleaning equipment so that the solution for each cleaning equipment can be controlled individually. If a cleaning equipment fails, the corresponding solution preparation system can control the cleaning equipment to stop the solution preparation. Relatively speaking, the control logic and control pipelines are much simpler and more reliable.

[0031] The drainage system allows all cleaning equipment to discharge waste liquid. The entire cleaning system can share a single liquid preparation system. That is, the drainage system is shared by two sets of cleaning equipment. The drainage system includes drainage branch pipes with first valves that are connected to the treatment tanks of each cleaning equipment, as well as drainage main pipes that are connected to all drainage branch pipes.

[0032] The water supply system provides cleaning water and chemical preparation water for the cleaning equipment, and can also be shared by two sets of cleaning equipment, thereby reducing costs.

[0033] The control system includes a fluid exchange control device and a fluid drain control device.

[0034] The liquid replacement control device controls the liquid dispensing system to deliver and proportion the required chemical solution to each processing tank. Based on the relationship between the chemical solution capacity and the weight of the silicon wafer, it calculates the remaining number of processing cycles for each processing tank. When the remaining number of processing cycles for a processing tank is less than 1, it sends a drain signal to the drain control device. The drain control device then controls the valve of the drain branch pipe connected to the corresponding processing tank in the drain system to drain the liquid. After that, the liquid replacement control device replaces the liquid in the corresponding processing tank.

[0035] In the above embodiments, the solution for the processing tank can be prepared according to the production plan, or the production plan can be planned according to the relationship between the solution capacity of the processing tank and the weight of the silicon wafers, or a combination of both. The production plan mainly refers to the production process and the number of silicon wafers to be processed. For example, the type of solution is determined according to the production process, the weight of silicon wafers that can be processed is calculated according to the capacity of the processing tank, and then the number of solution changes required is planned, etc.

[0036] This invention arranges two sets of cleaning equipment back-to-back, allowing them to share the same drainage system, saving costs and reducing space occupancy. Furthermore, the liquid replacement control device calculates the number of treatments required for each tank based on the relationship between the liquid capacity and the weight of the silicon wafers. For the same cleaning equipment, this calculation ensures that each tank within the same equipment has the same number of treatments, guaranteeing that all tanks within the same equipment reach the drainage condition after processing the same batch of silicon wafers. This eliminates the need to monitor only the remaining treatments in the upstream tank of a single cleaning system, avoiding the need for separate monitoring of different tanks and simplifying control costs. Moreover, the liquid dispensing process is fully automated, avoiding problems caused by human intervention.

[0037] Typically, a single cleaning device can process silicon wafers of a fixed size. That is, the surface area of ​​the silicon wafers processed by a single device has one or more specific dimensions. When the silicon wafer size is specific, its surface area can be represented by the formula S = f(G). The processing tank primarily performs wet processing on the silicon wafer surface; therefore, the solution capacity V is related to the silicon wafer surface area S, and consequently, the solution capacity V is related to the weight of the silicon wafer. In one embodiment, the total weight G of silicon wafers that can be processed by the solution capacity after preparation can be calculated in advance. 总 So, after each batch of silicon wafers is processed, the processing tank can use the formula [G] to determine the yield. 总 -(G0+…+G i )] / G i+1Calculations show that, since the number of silicon wafers processed in each batch may be the same or different, when the remaining processing cycles in the processing tank are less than 1, the tank can be drained. 总 G0 is the total weight of silicon wafers that can be processed based on the solution volume of the first treatment tank at the top of the cleaning equipment before processing begins. G0 is the weight of silicon wafers processed in the first treatment tank at the top of the cleaning equipment after solution preparation. i It is the weight of the silicon wafer most recently processed after solution preparation, G i+1 This is the weight of the next batch of silicon wafers to be processed.

[0038] This embodiment calculates the remaining number of processing cycles in the processing tank by weight, which is simpler to implement. Therefore, to check the quality of the cleaned silicon wafers, each batch of baskets in the cleaning equipment is weighed and recorded during loading. After cleaning in each processing tank (removing impurities), each silicon wafer will lose 0.4-0.5 grams in weight. Taking 600 wafers as an example, under normal cleaning quality, each basket will lose 240-300 grams at the unloading point. This is used to judge the quality of silicon wafer cleaning and also to determine whether the cleaning solution meets the requirements. Therefore, some existing cleaning equipment is equipped with corresponding weighing devices. This invention utilizes the weighing device at the loading point to calculate the remaining number of processing cycles in the processing tank, allowing the processing tank to be drained and the solution replaced in advance, improving production efficiency. This invention can also install a weighing device at the unloading point to determine the quality of silicon wafer cleaning.

[0039] In a preferred embodiment, the volume of the cleaning solution V can be controlled during solution preparation based on the relationship between the solution volume V and the weight of the silicon wafer. This ensures that the silicon wafers that can be processed in each tank of the same cleaning equipment are approximately or exactly the same weight, for example, all within the range of G. 总 Within the range of ±k, the control logic simplifies by focusing only on the remaining number of treatment cycles in the upstream treatment tank of a single cleaning device. Therefore, formula G... 总 / (G0+…+G i In ), G 总 G0 is the total weight of silicon wafers that can be processed based on the solution volume of the first treatment tank at the top of the cleaning equipment before processing begins. G0 is the weight of silicon wafers processed in the first treatment tank at the top of the cleaning equipment after solution preparation. i This is the weight of the silicon wafer most recently processed after solution preparation. This preferred embodiment simplifies the logic of the entire draining and changing solution control.

[0040] In a preferred embodiment, the draining device controls the sequential draining of each treatment tank in the same cleaning equipment according to its position within the cleaning equipment, proceeding from upstream to downstream. This can be described as draining the treatment tanks sequentially along the feeding-to-unloading direction. Each treatment tank can perform draining, cleaning, and solution preparation simultaneously with the last batch of cleaning (relative to the cleaning equipment), reducing the chemical treatment time and increasing equipment capacity. This can be understood as a "catch-up" draining process.

[0041] In one embodiment, the cleaning equipment further includes a level gauge for detecting the liquid level in the treatment tank.

[0042] The liquid replacement control device can calculate the cleaning time and drug preparation time of each treatment tank based on the signal from the level gauge during the cleaning and drug preparation process. The drain control device can calculate the drain time of each treatment tank based on the signal from the level gauge during the drain process.

[0043] In addition to the level gauge, the liquid exchange control device can also use one or more signals from the flow meter, valve opening, and thermometer to track cleaning time and chemical preparation time. To simplify control, the above embodiment only uses a level gauge to track the time for each process in the treatment tank; in this embodiment, the water in the chemical solution is hot water.

[0044] Since each cleaning device can independently complete the corresponding processing of silicon wafers, in a preferred embodiment, each group of cleaning devices includes one cleaning device, that is, two cleaning devices are set back to back and share a set of drainage systems. When the two cleaning devices are started, the cleaning device with the relatively faster preparation time of the chemical solution in the upstream processing tank is given priority in dispensing the solution, and the solution is dispensed at t 排1 *β% of the time elapsed, the upstream treatment tank, where the solution preparation time is relatively slow, begins to prepare the cleaning equipment. 排1 The draining time of the upstream treatment tank of the cleaning equipment that prioritizes liquid preparation, 0 < β < 100.

[0045] If the preparation time of the chemical solution in the upstream treatment tanks of two cleaning devices is the same, then one cleaning device can be randomly controlled to start the solution preparation first, and then... 排1 *β% of the time, control another cleaning device to start preparing the solution.

[0046] For example, β can be a value around 50, meaning the range of β is 50±A. Regardless of whether the two cleaning devices use the same process, the drainage of the two cleaning devices can be staggered for a certain period of time. This avoids the problem of slow drainage flow rate and reduced drainage rate when the main drainage pipe of the drainage system simultaneously handles the waste discharge of two cleaning devices. By staggering the production and / or drainage of the two back-to-back cleaning devices, this situation is avoided. The staggered time between the two cleaning devices should not be less than 2 hours.

[0047] In a further embodiment, the drainage system further includes a buffer branch pipe with a second valve connected to each of the treatment tanks, at least one buffer tank connected to the buffer branch pipe, and the drainage port of the buffer tank being connected to the main drainage pipe.

[0048] Although the solution preparation times of the two sets of cleaning equipment were staggered in the previous embodiments, i.e., the drainage times were staggered at the beginning, since this invention involves two sets of cleaning equipment, the processes of the two sets of cleaning equipment may be the same or different, especially when they are different. Due to the different reaction times and drainage times of each treatment tank, multiple treatment tanks may need to be drained as soon as possible. Therefore, setting up a buffer tank, even just one buffer tank, can effectively avoid this situation. In particular, setting up a buffer tank will not increase the complexity of the drainage system and can avoid drainage conflicts between the two sets of cleaning equipment.

[0049] In a preferred embodiment, the drain control device calculates the buffer time difference of the next processing tank after the upstream processing tank of the two cleaning devices. It is important to note that this refers to the upstream processing tank. At the initial startup of the cleaning system, the upstream processing tank is the same as the first processing tank (the upstream processing tank) of the cleaning device. However, as draining proceeds sequentially, at any subsequent point in time, the upstream processing tank may be the second, third, or nth processing tank. Therefore, the next processing tank after the upstream processing tank refers to the corresponding third, fourth, or (n+1)th processing tank.

[0050] The buffer time difference of the processing tank is calculated using the formula Δt = t 排2 +t 配2 +t 洗2 -t 下游处理 -t 配1 -t 洗1 Calculate and, when the buffer time difference is greater than γ, control the treatment tank to drain liquid through the buffer branch pipe, γ≥0, t 排2 t 洗2 and t 下游处理 These are the drainage time, cleaning time, and total processing time of the next processing tank after the upstream processing tank containing the solution to be prepared, respectively, t. 配1 and t 洗1 This refers to the solution preparation time and cleaning time for the upstream treatment tank containing the solution to be prepared within the same cleaning equipment.

[0051] This embodiment calculates the required drainage time, solution preparation time, and cleaning time of the processing tank, and then subtracts the downstream processing time, the solution preparation time, and the cleaning time of the previous processing tank to obtain a buffer time difference. When the buffer time difference is γ, it means that the processing tank takes a long time from the start of drainage to being fully ready to process the next batch of silicon wafers. If the drainage priority of the processing tank cannot be increased, even if the previous processing tank has finished processing the corresponding silicon wafers, it will still need to wait for the processing tank for a long time, which is not conducive to the optimization of the production line. Therefore, in this case, the drainage priority of the processing tank is increased, and the drainage is carried out through the buffer tank. Then, the buffer tank can discharge the waste liquid to the main drainage pipe according to the timing to avoid pipe congestion, thereby improving the efficiency of the production line.

[0052] In the above embodiments, the liquid replacement control device may also be equipped with a one-button start / stop function. When the detection device detects an abnormality, the liquid replacement control device can pause or restart the liquid preparation function through the one-button start / stop function.

[0053] Figure 1 A preferred embodiment of the cleaning system of the present invention is shown, in which two cleaning devices are arranged back to back, so that the two cleaning devices 1 are used in the same drainage system 7 and hot water machine (water supply system), which can save a set of water supply system and drainage system.

[0054] In this system, the robotic arm 2 is positioned along the processing direction of the cleaning equipment. Multiple processing tanks 3 are arranged sequentially within the two cleaning devices 1. Each cleaning device is equipped with a liquid change control device; the drain control device is not shown in the figure. A feeding device 5 is located on the left side of the cleaning equipment, and a basket 6 is mounted on the feeding device 5. In this embodiment, the drain branch pipes and main drain pipes of the drain system 7 have a fishbone-shaped structure when viewed from above. The drain system 7 is connected to the wastewater tank 8, and each processing tank is connected to a drain branch pipe equipped with a manual valve 701 and a solenoid valve 702.

[0055] After applying the technical solution of this invention, the cleaning system can automatically calculate the remaining cleaning cycles of the treatment tank solution. When the remaining cycles are less than one, no manual operation is required. The control system, in conjunction with the treatment tank, drainage system, and dispensing system, enables automatic discharge, self-washing, and dispensing of the treatment tank solution without manual proportioning. It also adds a one-button start / stop dispensing function to prevent the need for re-dispensing or stopping the dispensing process in case of emergencies. The treatment tank consists of a main tank and a secondary tank. The secondary tank is connected to the main tank by a circulation pipe for circulation. It is also equipped with an inlet pipe, a drain pipe, a thermometer, a level gauge (magnetostrictive level gauge, ultrasonic level gauge, etc.), and pumps, manual valves, solenoid valves, and flow meters (measuring tanks) on the pipes.

[0056] Figure 2The invention illustrates a specific method of use. A specific production plan can be formulated based on the relationship between the liquid capacity and the weight of the silicon wafers. The liquid replacement control device controls the liquid dispensing system to prepare the required liquid for each processing tank according to specific process requirements. The liquid includes acidic and / or alkaline solutions. Then, the weight of the silicon wafers weighed at the loading point is counted. The weight of silicon wafers already processed by the liquid in each batch of the corresponding processing tank (which can be the processing tank that can process the fewest silicon wafers, all processing tanks, or the upstream processing tank) is also counted. Given the minimum weight of silicon wafers processed in each batch, or the weight of the next batch of silicon wafers, the liquid replacement control device can calculate the remaining number of processing cycles for each processing tank based on the relationship between the liquid capacity and the weight of the silicon wafers. If the remaining number of cycles for a corresponding processing tank is less than 1, the liquid discharge control device controls the corresponding processing tank to discharge the liquid.

[0057] For example, if each processing tank is counted separately, then the tank with less than 1 remaining cycles will be drained. If all processing tanks have similar capacity to process silicon wafers, the upstream tank or the tank with the fewest silicon wafers will be selected for monitoring. Then, when the remaining cycles of that tank are less than 1, the drain control device will control each processing tank of the cleaning equipment to perform catch-up draining. Draining, cleaning, and liquid preparation can be carried out at the same time as the last batch of cleaning, reducing the liquid treatment time and increasing the equipment capacity. This can be understood as "catch-up" liquid replacement, where each cleaning tank (or multiple cleaning tanks as a batch) is prepared and replaced sequentially in the direction from loading to unloading.

[0058] Taking texturing as an example, each batch of silicon wafers is processed in the same quantity and weight. It is calculated that the new cleaning solution can be used for 200 batches of cleaning. When the cleaning solution is used for the 200th cleaning cycle, the remaining cycles are 0 (less than 1), so the feeding device stops feeding. At this time, the 200th cleaning cycle is in progress. When the basket is cleaned in the first processing tank and placed in the second processing tank, the drainage system of the first processing tank starts draining. After drainage, pure water is used to rinse the remaining cleaning solution in the tank through the inlet pipe. After cleaning, the solution is prepared. A flow meter (or metering tank) can be installed on the liquid exchange pipe, connected to a computer, to control the ratio and complete the solution preparation for the first processing tank. When the basket is in the second processing tank... After cleaning is completed in the first treatment tank, the second treatment tank repeats the draining, cleaning, and dispensing process of the first treatment tank when the basket enters the third treatment tank. When the basket enters the fifth treatment tank, the third treatment tank is draining (cleaning and dispensing), and the fourth treatment tank can also drain (cleaning and dispensing) at the same time to further improve dispensing efficiency. At this time, the third and fourth treatment tanks are the same batch of tanks for liquid replacement, saving dispensing time. Until the basket is cleaned, the last tank is also dispensing, realizing dispensing while cleaning. After all tanks have been cleaned and dispensed, the temperature of the liquid in each tank is tested to see if it meets the standard. Once it meets the standard, the new liquid is used and the equipment starts to be loaded.

[0059] The processing tank of this invention consists of a main tank and a secondary tank. The secondary tank is connected to the main tank by a circulation pipe for circulation and overflow. It is also equipped with an inlet pipe, a drain pipe, a thermometer, and a level gauge (magnetostrictive level gauge, ultrasonic level gauge, etc.). Depending on the process, the cleaning tank can be selected to always maintain an overflow state. The main tank overflows through the overflow port and flows into the secondary tank. The secondary tank is connected by a circulation pipe (the pipe is equipped with a circulation pump, a manual valve, and a solenoid valve). The thermometer is mainly used to detect the temperature of the medicine solution in the tank. The level gauge is used to monitor and prevent the tank from breaking or other reasons that cause the medicine solution level in the tank to be extremely low and fail to be detected in time, resulting in poor cleaning effect. The liquid replacement system includes a liquid replacement tank, a liquid replacement pipe, a pump, a manual valve, a solenoid valve, and a flow meter (measuring tank). The liquid replacement system is connected to the inlet pipe of part 301, which includes solutions such as pure water (hot water), HCl, H2O2, NaOH, and KOH. The flow meter can monitor and mix the solutions according to the preset medicine solution ratio.

[0060] This invention uses computer-controlled liquid replacement, drainage, and cleaning of the treatment tank to complete the liquid preparation without manual operation. The computer also features a one-button start / stop function for liquid preparation to prevent emergency situations requiring restarting or stopping the process. It can also record and analyze the weight of the wafer baskets. The baskets are weighed during loading, and after cleaning (removing impurities), each wafer will lose an average of approximately 0.4-0.5 grams. For example, with 600 wafers, under normal cleaning quality, each basket will lose 240-300 grams. This information is used to determine the quality of silicon wafer cleaning and whether the cleaning solution meets requirements.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A cleaning system, characterized in that, include: Two sets of cleaning equipment are set back to back. Each set of cleaning equipment includes at least one cleaning device. Each cleaning device includes multiple processing tanks arranged in sequence, a first weighing device set at the loading point for weighing the silicon wafers before processing, and a second weighing device set at the unloading point for weighing the silicon wafers after processing. The solution preparation system delivers and proportions the required pharmaceutical solution to the treatment tank. The drainage system is shared by two sets of cleaning equipment. The drainage system includes drainage branch pipes with first valves that are connected to the treatment tanks of each cleaning equipment in a one-to-one correspondence, and a drainage main pipe that is connected to the drainage branch pipes. A water supply system shared by two sets of cleaning equipment provides cleaning water and chemical preparation water for the cleaning equipment. The control system includes a liquid replacement control device and a liquid discharge control device. The liquid replacement control device controls the liquid preparation system to deliver and proportion the required chemical solution to the processing tank. Based on the relationship between the chemical solution volume and the weight of the silicon wafer, it calculates the remaining number of processing cycles for each processing tank. When the remaining number of processing cycles for a processing tank is less than 1, it sends a liquid discharge signal to the liquid discharge control device. The liquid discharge control device then controls the valve of the liquid discharge branch pipe connected to the corresponding processing tank in the liquid discharge system to discharge the liquid. After that, the liquid replacement control device replaces the liquid in the corresponding processing tank.

2. The cleaning system as described in claim 1, characterized in that, The remaining number of processing cycles in the processing tank is determined by the formula [G]. 总 -(G0+…+G i )] / G i+1 Calculations show that G 总 G0 is the total weight of silicon wafers that can be processed based on the solution volume of the first treatment tank at the top of the cleaning equipment before processing begins. G0 is the weight of silicon wafers processed in the first treatment tank at the top of the cleaning equipment after solution preparation. i It is the weight of the silicon wafer most recently processed after solution preparation, G i+1 This is the weight of the next batch of silicon wafers to be processed.

3. The cleaning system as described in claim 1, characterized in that, The drainage control device controls each treatment tank in the same cleaning equipment to drain liquid sequentially from upstream to downstream, according to the position of the treatment tank in the cleaning equipment.

4. The cleaning system as described in claim 3, characterized in that, The cleaning equipment also includes a level gauge for detecting the liquid level in the treatment tank. The liquid replacement control device calculates the cleaning time and preparation time of each treatment tank based on the signal from the level gauge during the cleaning and dispensing process. The drain control device calculates the draining time based on the signal from the level gauge during the draining process.

5. The cleaning system as described in claim 4, characterized in that, Each group of cleaning equipment includes one cleaning device. When two cleaning devices are started, the cleaning device with the relatively faster solution preparation time in the upstream treatment tank is given priority in solution preparation, and the solution is prepared within t... 排1 *β% of the time elapsed, the upstream treatment tank, where the solution preparation time is relatively slow, begins to prepare the cleaning equipment. 排1 The draining time of the upstream treatment tank of the cleaning equipment that prioritizes liquid preparation, 0 < β < 100.

6. The cleaning system as described in claim 5, characterized in that, The drainage system also includes a buffer branch pipe with a second valve connected to each of the treatment tanks, at least one buffer tank connected to the buffer branch pipe, and the drainage port of the buffer tank is connected to the main drainage pipe.

7. The cleaning system as described in claim 6, characterized in that, The drainage control device calculates the buffer time difference Δt=t between the upstream treatment tank and the next treatment tank in the two cleaning devices. 排2 +t 配2 +t 洗2 -t 下游处理 -t 配1 -t 洗1 And when the buffer time difference is greater than γ, the treatment tank is controlled to drain through the buffer branch pipe, γ≥0, t 排2 t 配2 t 洗2 and t 下游处理 The time t represents the drainage time, solution preparation time, and cleaning time of the next processing tank after the upstream processing tank, as well as the total processing time of its downstream processing tank. 配1 and t 洗1 This refers to the solution preparation time and cleaning time for the upstream treatment tank containing the solution to be prepared within the same cleaning equipment.

8. The cleaning system according to any one of claims 1 to 7, characterized in that, The liquid replacement control device is set up one-to-one with the cleaning equipment. The liquid replacement control device is equipped with a one-button start / stop function. When the detection device detects an abnormality, the liquid replacement control device can pause or restart the liquid preparation function through the one-button start / stop function.

9. The cleaning system according to any one of claims 1 to 7, characterized in that, The solution includes acidic and / or alkaline solutions.

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