CN114632759A - Efficiency-improving cleaning method for large-size monocrystalline silicon wafer - Google Patents

Abstract

The invention relates to a method for improving efficiency and cleaning a large-size monocrystalline silicon wafer, which comprises the following process flows of: degumming and pre-cleaning, inserting sheet feeding, pure water overflow ultrasonic rinsing, first ultrasonic alkali washing, second ultrasonic alkali washing, third ultrasonic alkali washing, pure water overflow ultrasonic rinsing, hydrogen peroxide ultrasonic rinsing, first pure water ultrasonic rinsing, second pure water ultrasonic rinsing, third pure water ultrasonic rinsing, fourth pure water overflow ultrasonic rinsing, pre-dewatering, drying tank and blanking; the invention aims at large-size silicon wafers, improves the cleaning capability, reduces the texturing reject ratio and improves the conversion efficiency.

Description

Efficiency-enhancing cleaning method for large-size monocrystalline silicon wafers

technical field

The invention relates to a cleaning method for improving the efficiency of large-sized single crystal silicon wafers, and belongs to the technical field of post-processing of cutting silicon wafers.

Background technique

At present, solar monocrystalline silicon wafers have all been cut by diamond wire, which has obvious advantages such as high cutting efficiency, low silicon consumption and low cost. However, compared with the original mortar structure line silicon wafer, the diamond wire-cut silicon wafer has a rougher surface and more pits, and the residual organic matter, inorganic matter, metal ions, silicon powder particles and other impurities generated during the cutting process are highly absorbent.

At the same time, the trend of large-size silicon wafers is increasing and downstream cells are pursuing greater efficiency. The size of silicon wafers is getting larger and larger, and the requirements for the surface cleanliness of the original silicon wafers are higher, so higher requirements are placed on the cleaning process. For example, the application No. 201110251543.7 discloses a "cleaning method for diamond wire-cut silicon wafers", and the application No. 201110111779.0 discloses "a cleaning method for diamond wire-cut silicon wafers". The cleaning methods in the two publications are mainly It is suitable for single / polycrystalline regular size silicon wafers, and its cleaning ability is difficult to remove impurities on the surface of large size silicon wafers, which affects the subsequent texturing effect and photoelectric conversion efficiency.

Therefore, it is urgent to develop a new cleaning process, which is different from the conventional size silicon wafer cleaning process, so as to improve the cleaning ability of large-size silicon wafers and reduce the defect rate of texturing.

SUMMARY OF THE INVENTION

The invention provides a cleaning method for improving the efficiency of a large-sized single crystal silicon wafer, aiming at the large-sized silicon wafer, the cleaning capability is improved, the texturing defect rate is reduced, and the conversion efficiency is improved.

The technical scheme adopted by the present invention to solve its technical problems is:

A method for cleaning large-size monocrystalline silicon wafers with improved efficiency, which specifically includes the following steps:

Step S1: pre-cleaning and degumming the ingot after cutting, after the pre-cleaning and degumming, take out the silicon wafer according to the width of the matching partition, and put it into the turnover water tank in sequence in the same direction;

Step S2: take out the silicon wafer from the turnover water tank and put it into the material holder, and the wafer inserter sends it into the flower basket in parallel;

Step S3: immersing the silicon wafer into the medicament tank body with the function of overflowing and replenishing water, and performing the first ultrasonic pre-cleaning;

Step S4: immersing the silicon wafer that has undergone the first ultrasonic pre-cleaning into the tank body of the chemical tank to perform the first ultrasonic chemical cleaning;

Step S5: continue to immerse the silicon wafer after the first ultrasonic cleaning in the chemical tank, and perform the second ultrasonic cleaning;

Step S6: immersing the silicon wafer after the second ultrasonic chemical cleaning into the chemical tank body again, and performing the third ultrasonic chemical cleaning;

Step S7: After three times of ultrasonic chemical alkali cleaning, the silicon wafer is immersed in the chemical tank body with the overflow water replenishing function, and ultrasonic pre-cleaning is performed;

Step S8: ultrasonically rinse the silicon wafer obtained in step S7 with hydrogen peroxide in a hydrogen peroxide tank;

Step S9: the silicon wafer after ultrasonic rinsing with hydrogen peroxide enters the fourth-stage overflow for the first rinsing;

Step S10: the silicon wafers rinsed for the first time by the four-stage overflow enter the fourth-stage overflow for the second rinse;

Step S11: the silicon wafers rinsed for the second time by the four-stage overflow enter the fourth-stage overflow for the third rinse;

Step S12: the silicon wafers that have been rinsed for the third time by the four-stage overflow enter the pharmacy tank body with the overflow water replenishment function for the fourth-stage overflow rinsing;

Step S13: placing the silicon wafers that have been rinsed four times in a slow lifting tank for pre-dehydration, and the slow lifting tank contains pure water;

Step S14: putting the pre-dehydrated silicon wafer into a drying tank for drying;

Step S15: After the dried silicon wafers are inspected by the sorting machine and manually re-inspected, they are packaged and put into storage according to their grades;

As a further preference of the present invention, the pre-cleaning and degumming treatment of the crystal rod in step S1 specifically includes:

Step S111: insert a special partition plate according to the width of 60±10mm in the crystal rod, and slowly push it into the feeding area of the degumming machine;

Step S112: set the temperature of the degumming tank to 55±5°C, the time of the degumming tank to be 10±2min, the degumming agent to use degumming agent and lactic acid, and the concentration of the degumming tank to be added at a ratio of 10-15% of the volume of the degumming tank;

Step S113: Set the degumming process parameters of the degumming machine, specifically set the degumming spray time to 10±2min, the spray water pressure to be 0.02-0.05Mpa, the water temperature to be 20-30°C, and the water quality to be tap water or concentrated water or return water. When spraying with water, adjust the spray pipe so that the nozzle is facing the partition, and the distance is 10-20mm, and the nozzle of the spray pipe is in the shape of a bell mouth for mist spraying;

Step S114: after the degumming process is completed, take out the silicon wafer according to the width of the partition, wipe the four end faces and chamfered positions of the silicon wafer, and finally put it into the turnover water tank;

As a further preference of the present invention, during the first ultrasonic pre-cleaning in step S3, the cleaning time of the pharmaceutical tank is set to be 220±20s, the temperature to be 45±5°C, the ultrasonic intensity power to be 24±2KHz, and the ultrasonic current to be 5 ±0.5A, the water quality in the chemical tank is pure water;

As a further preference of the present invention, the multiple ultrasonic alkaline washings performed in steps S4 to S6 all use conventional two-component silicon wafer cleaning agents, and are proportioned according to the ratio of alkaline agent and active agent to 2:1;

Among them, in the initial addition, the alkaline agent should be added according to 4-4.5% of the volume of the tank body of the medicine tank, and the active agent should be added according to 2.0-2.25% of the volume of the tank body of the medicine tank; during the ultrasonic alkali cleaning, the cleaning time should be set to 220±20s , the temperature is 55±5℃, the ultrasonic intensity power is 24±2KHz, the ultrasonic current is 5±0.5A, and the water quality in the medicine tank is pure water;

As a further preference of the present invention, in step S7, when ultrasonic pre-cleaning is performed again, the cleaning time is set to be 220±20s, the temperature to be 45±5°C, the ultrasonic intensity power to be 24±2KHz, and the ultrasonic current to be 5±0.5A, The water quality in the chemical tank is pure water;

As a further preference of the present invention, in step S8, the hydrogen peroxide is a strong oxidant, and when the hydrogen peroxide is initially added, the concentration of the original solution of the hydrogen peroxide is 7-8%, which is 15±2% of the volume of the tank body of the medicine tank, and the caustic soda is the tank body of the medicine tank 0.10-0.15% of the volume;

Set the cleaning time of the chemical tank to be 220±20s, the temperature to be 40±5℃, the ultrasonic intensity power to be 24±2KHz, the ultrasonic current to be 5±0.5A, and the water quality in the chemical tank to be pure water;

As a further preference of the present invention, for the multiple times of pure water ultrasonic rinsing performed in steps S9 to S11, the cleaning time of the pharmaceutical tank is set to be 220±20s, the temperature is 50±5°C, the ultrasonic intensity power is 24±2KHz, and the ultrasonic The current is 5±0.5A, and the water quality in the chemical tank is pure water;

As a further preference of the present invention, in step S12, during the fourth rinsing of the four-stage overflow, set the cleaning time of the pharmaceutical tank to be 220±20s, the temperature to be 55±5°C, the ultrasonic intensity power to be 24±2KHz, and the ultrasonic power to be 24±2KHz. The current is 5±0.5A, and the water quality in the chemical tank is pure water;

As a further preference of the present invention, in step S13, the cleaning time of the slow-lift tank is set to be 100±10s, the temperature to be 85±5°C, and the water quality in the slow-lift tank is pure water;

As a further preference of the present invention, in step S14, the total drying time of the drying tank is set to be 400±20s and the temperature to be 95±5°C.

Through the above technical solutions, with respect to the prior art, the present invention has the following beneficial effects:

1. The cleaning method provided by the present invention has strong adaptability, and improves the cleaning capacity under the premise of ensuring the reasonable cost of the agent;

2. In the cleaning method provided by the present invention, by adding a four-stage overflow rinsing function, it is possible to formulate and calculate the concentration of the agent that is more suitable for large-sized silicon wafers;

3. In the cleaning method provided by the present invention, the addition of the chemical agent is carried out in a step-by-step manner during cleaning, which balances the cleaning ability and avoids the deterioration of the chemical agent;

4. With the cleaning method provided by the present invention, the defect rate of texturing is lower than that of the same period by 0.04-0.08%, and the photoelectric conversion efficiency is increased by 0.02-0.03%.

Detailed ways

At present, the cleaning methods for diamond wire-cut silicon wafers on the market are all aimed at conventional size silicon wafers. However, as pointed out in the background art, in order to maximize the efficiency of downstream cells, the size of silicon wafers is getting larger and larger, exceeding the conventional size. Therefore, the cleaning method of the prior art can no longer meet the requirements for the cleanliness of the surface of the silicon wafer, and a more finely matched cleaning process needs to be formulated to achieve the purpose of improving the quality of the original silicon wafer.

Based on this, the present application provides a method for cleaning large-size monocrystalline silicon wafers with improved efficiency, which specifically includes the following steps:

Step S1: pre-cleaning and degumming the ingot after cutting, after the pre-cleaning and degumming, take out the silicon wafer according to the width of the matching partition, and put it into the turnover water tank in sequence in the same direction;

Specifically include:

Step S111: insert a special partition plate according to the width of 60±10mm, slowly push it into the feeding area of the degumming machine, and prepare to enter the degumming tank;

Step S112: The temperature and time of the degumming tank need to be strictly controlled, which has a certain impact on the residual impurities on the surface of the silicon wafer. High temperature and long time are very unfavorable for the cleanliness of the next process. Therefore, the temperature of the degumming tank is set to 55± 5 ℃, the degumming tank time is 10±2min, the degumming agent is degumming agent and lactic acid, and the concentration of the degumming tank is added according to the proportion of 10-15% of the volume of the degumming tank;

Step S113: Set the degumming process parameters of the degumming machine, specifically set the degumming spray time to 10±2min, the spray water pressure to be 0.02-0.05Mpa, the water temperature to be 20-30°C, and the water quality to be tap water or concentrated water or return water. When spraying with water, adjust the spray pipe so that the nozzle is facing the partition, and the distance is 10-20mm, and the nozzle of the spray pipe is in the shape of a bell mouth to spray mist. This adjustment can make the pre-cleaning effect of the silicon wafer better. It is good for subsequent processing;

Step S114 : after the degumming process is completed, take out the silicon wafer according to the width of the separator, wipe the four end faces and chamfered positions of the silicon wafer, and finally put it into the turnover water tank to prepare for the next process of insert cleaning.

Step S2: Loading the wafers: Take the silicon wafers out of the turnover water tank and put them into the material tray, and the wafer insertion machine will send them into the flower basket. Pay attention to the direction of the line marks when placing the material support here, and send them into the flower basket in parallel.

Step S3: pure water overflow ultrasonic rinsing: the silicon wafer is immersed in the medicament tank body with the overflow water replenishment function, and the first ultrasonic pre-cleaning is performed; 45±5℃, the ultrasonic intensity power is 24±2KHz, the ultrasonic current is 5±0.5A, and the water quality in the tank is pure water. During cleaning, the silicon wafers have the most impurities remaining, and frequent cleaning makes the water in the tank easily dirty. Therefore, with the function of overflowing water, it can ensure that the water quality in the tank always meets the cleaning requirements.

Step S4: the first ultrasonic alkali cleaning: immerse the silicon wafer after the first ultrasonic pre-cleaning into the tank body of the chemical tank to carry out the first ultrasonic chemical cleaning; use a conventional two-component silicon wafer cleaning agent, according to the alkali agent and activity The proportion of the agent is 2:1; among them, in the initial addition, the alkali agent is added according to 4-4.5% of the volume of the tank body of the agent tank, and the active agent is added according to 2.0-2.25% of the volume of the tank body of the agent tank; ultrasonic alkaline washing When the cleaning time is 220±20s, the temperature is 55±5℃, the ultrasonic intensity power is 24±2KHz, the ultrasonic current is 5±0.5A, and the water quality in the chemical tank is pure water.

Step S5: the second ultrasonic alkaline cleaning: continue to immerse the silicon wafer cleaned by the first ultrasonic chemical into the chemical tank for the second ultrasonic cleaning; use a conventional two-component silicon wafer cleaning agent, according to the alkaline chemical and The active agent is proportioned at a ratio of 2:1; among them, in the initial addition, the alkali agent is added according to 4-4.5% of the volume of the tank body of the agent tank, and the active agent is added according to 2.0-2.25% of the volume of the tank body of the agent tank; ultrasonic alkali When washing, set the cleaning time to 220±20s, the temperature to be 55±5℃, the ultrasonic intensity power to be 24±2KHz, the ultrasonic current to be 5±0.5A, and the water quality in the medicine tank to be pure water.

Step S6: the third ultrasonic alkaline cleaning: the silicon wafers cleaned by the second ultrasonic chemical are immersed in the chemical tank again, and the third ultrasonic cleaning is carried out; The active agent is proportioned at a ratio of 2:1; among them, in the initial addition, the alkali agent is added according to 4-4.5% of the volume of the tank body of the agent tank, and the active agent is added according to 2.0-2.25% of the volume of the tank body of the agent tank; ultrasonic alkali When washing, set the cleaning time to 220±20s, the temperature to be 55±5℃, the ultrasonic intensity power to be 24±2KHz, the ultrasonic current to be 5±0.5A, and the water quality in the medicine tank to be pure water.

Step S7: Ultrasonic rinsing with pure water overflow: after three ultrasonic chemical alkaline washings, the silicon wafer is immersed in a chemical tank with overflow water replenishment function for ultrasonic pre-cleaning; the same chemical tank here needs to have an overflow water supplement function. This is because the amount of medicine in the tank in this step is small, and it is necessary to remove a part of the residual medicine on the surface of the silicon wafer, and then enter the next hydrogen peroxide tank; when the pure water overflows ultrasonic rinsing, set the cleaning time to 220± 20s, the temperature is 45±5℃, the ultrasonic intensity power is 24±2KHz, the ultrasonic current is 5±0.5A, and the water quality in the medicine tank is pure water.

Step S8: The silicon wafer obtained in step S7 is subjected to ultrasonic rinsing with hydrogen peroxide in a hydrogen peroxide water tank; hydrogen peroxide is a strong oxidant, has strong bactericidal and antioxidative abilities, and volatilizes quickly. After the silicon wafer rinsed once is rinsed in the hydrogen peroxide water tank, An effective protective layer is formed on the surface of the silicon wafer, and the uniformity and coverage area ratio of the subsequent alkali-textured silicon wafer are high; however, there are strict regulations on the amount of hydrogen peroxide used in this step. Specifically, the initial addition of hydrogen peroxide When the concentration of the original solution of hydrogen peroxide is 7-8%, it is 15±2% of the volume of the medicine tank, and the caustic soda is 0.10-0.15% of the volume of the medicine tank; the cleaning time of the medicine tank is set to 220±20s, the temperature The temperature is 40±5℃, the ultrasonic intensity power is 24±2KHz, the ultrasonic current is 5±0.5A, and the water quality in the medicine tank is pure water.

Step S9: the silicon wafer after ultrasonic rinsing with hydrogen peroxide enters the first rinsing of the four-stage overflow; specifically, the cleaning time of the chemical tank is set to 220±20s, the temperature is 50±5°C, and the ultrasonic intensity power is 24±2KHz , the ultrasonic current is 5±0.5A, and the water quality in the chemical tank is pure water.

Step S10: the silicon wafers that have been rinsed for the first time in the fourth-stage overflow enter the second-stage overflow for the second rinsing; the cleaning time of the chemical tank is set to 220±20s, the temperature is 50±5°C, and the ultrasonic intensity power is 24±24± 2KHz, ultrasonic current is 5±0.5A, and the water quality in the chemical tank is pure water.

Step S11: the silicon wafer after the second rinsing of the fourth-stage overflow enters the fourth-stage overflow for the third rinsing; the cleaning time of the chemical tank is set to 220±20s, the temperature is 50±5℃, and the ultrasonic intensity power is 24±24± 2KHz, ultrasonic current is 5±0.5A, and the water quality in the chemical tank is pure water.

Step S12: The silicon wafers that have been rinsed for the third time by the four-stage overflow enter the tank body of the drug tank with the overflow and water replenishment function to perform the fourth-level overflow and the fourth rinsing; With the overflow replenishment function, it can ensure that the water quality of the third-level overflow rinsing tank meets the standard; when the fourth-level overflow is used for the fourth rinsing, set the cleaning time of the chemical tank to 220±20s, the temperature to 55±5℃, and the ultrasonic intensity power to be 220±20s. 24±2KHz, ultrasonic current is 5±0.5A, and the water quality in the chemical tank is pure water.

Step S13: placing the silicon wafers rinsed four times in the slow-lift tank for pre-dehydration, and the water quality in the slow-lift tank is pure water; during pre-dehydration, the slow-lift tank needs a higher temperature and ensures that the temperature rise speed is kept uniform, In order to ensure uniform dehydration of silicon wafers, in order to achieve uniform dehydration effect, the inverter parameters are set to control the adjustment according to the actual dehydration effect; therefore, the cleaning time of the slow lifting tank is set to 100±10s, and the temperature is 85±5℃ , the water quality in the slow-lift tank is pure water.

Step S14: put the pre-dehydrated silicon wafers into the drying tank for drying. The drying tank needs to maintain a relatively high temperature and sufficient drying time. Therefore, the total drying time of the drying tank is set to be 400± 20s, the temperature is 95±5℃;

Step S15: After the dried silicon wafers are inspected by the sorting machine and manually re-inspected, they are packaged and put into storage according to their grades.

What needs to be added here is that, in order to ensure the cleaning effect, a preference is also provided for the replenishment and water replacement of the chemical tank. The silicon wafer is washed to 20,000 pieces, and the cleaning agent A 1% and the cleaning agent B are added according to the volume of the tank. 0.5%, add 2% to the hydrogen peroxide tank, wash the silicon wafers to 40,000 pieces, add 1.5% of cleaning agent A, 0.75% of cleaning agent B according to the volume of the tank, add 4% to the hydrogen peroxide tank, and wash to 60,000 pieces. All water needs to be changed.

The applicant has verified the efficiency-enhancing cleaning method for large-size monocrystalline silicon wafers provided by this application, mainly for large-size silicon wafers, using conventional cleaning processes and the cleaning methods provided by this application to conduct tests and comparisons, and obtain the following table. The data,

It can be seen from the table that using conventional methods 1 and 2, the cleaning time is short, the water changing cycle is long, the soiling rate and the rate of defective texturing and downgrading are both higher; using conventional methods 3 and 4, compared with conventional methods 1 and 4, 2. The cleaning time is extended, the amount of cleaning agent is also reduced, and the water change cycle in the tank is shortened, so the soiling rate and the defect rate of texturing and downgrading have been slightly reduced. However, compared with the new process provided in this application, the application has adjusted the cleaning time, the dosage of chemicals and the water change cycle, but the soiling rate and the defective rate of texturing downgrade are greatly reduced, and the defective rate of texturing is lower than In the same period, 0.04-0.08%, the photoelectric conversion efficiency increased by 0.02-0.03%, and the overall effect is the best. Therefore, the cleaning method provided by the present application is worthy of popularization and use.

It will be understood by one of ordinary skill in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms such as those defined in the general dictionary should be understood to have meanings consistent with their meanings in the context of the prior art and, unless defined as herein, are not to be taken in an idealized or overly formal sense. explain.

The meaning of "and/or" described in this application means that each of them exists alone or both are included.

The meaning of "connection" described in this application may be a direct connection between components or an indirect connection between components through other components.

Taking the above ideal embodiments according to the present invention as inspiration, and through the above description, relevant personnel can make various changes and modifications without departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the contents in the specification, and the technical scope must be determined according to the scope of the claims.

Claims (10)

1. A method for increasing the efficiency and cleaning a large-size monocrystalline silicon wafer is characterized by comprising the following steps: the method specifically comprises the following steps:

step S1: pre-cleaning and degumming treatment are carried out on the cut crystal bars, after the crystal bars are pre-cleaned and degummed, the silicon wafers are taken out according to the width of the matching partition plate and are sequentially placed into a turnover water tank in the same direction;

step S2: taking the silicon wafer out of the turnover water tank, putting the silicon wafer into a material tray, and parallelly conveying the silicon wafer into a flower basket by using a wafer inserting machine;

step S3: immersing a silicon wafer into a medicament tank body with an overflow water replenishing function, and performing primary ultrasonic precleaning;

step S4: immersing the silicon wafer subjected to the first ultrasonic pre-cleaning into a medicament tank body, and carrying out first ultrasonic medicament cleaning;

step S5: continuously immersing the silicon wafer subjected to the first ultrasonic medicament cleaning into a medicament groove body, and carrying out second ultrasonic medicament cleaning;

step S6: immersing the silicon wafer subjected to the second ultrasonic medicament cleaning into the medicament groove body again, and carrying out third ultrasonic medicament cleaning;

step S7: after three times of ultrasonic medicament alkali washing, immersing the silicon wafer into a medicament tank body with an overflow water replenishing function, and carrying out ultrasonic pre-cleaning;

step S8: performing hydrogen peroxide ultrasonic rinsing on the silicon wafer obtained in the step S7 through a hydrogen peroxide tank;

step S9: the silicon wafer after the hydrogen peroxide ultrasonic rinsing enters a four-stage overflow first rinsing;

step S10: the silicon wafer subjected to the first rinsing of the four-stage overflow enters the second rinsing of the four-stage overflow;

step S11: the silicon wafer subjected to the secondary rinsing of the fourth-stage overflow enters the third rinsing of the fourth-stage overflow;

step S12: the silicon wafer subjected to the fourth-stage overflow third rinsing enters a medicament tank body with an overflow water supplementing function to carry out fourth-stage overflow rinsing;

step S13: placing the silicon wafer rinsed for four times in a slow lifting tank for pre-dehydration, wherein pure water is contained in the slow lifting tank;

step S14: putting the silicon wafer subjected to pre-dehydration into a drying groove for drying;

step S15: and (4) after the dried silicon wafer is subjected to sorter detection and manual reinspection, packaging according to grades and warehousing.

2. The method for enhancing the efficiency and cleaning the large-size monocrystalline silicon wafer according to claim 1, wherein: the pre-cleaning and degumming treatment of the crystal bar in the step S1 specifically comprises the following steps:

step S111: inserting a special clapboard into the crystal bar according to the width of 60 +/-10 mm, and slowly pushing the crystal bar into a feeding area of a degumming machine;

step S112: setting the temperature of a degumming tank to be 55 +/-5 ℃, the time of the degumming tank to be 10 +/-2 min, wherein degumming agents are degumming agents and lactic acid, and the concentration of the degumming tank is added according to the proportion of 10-15% of the volume of the body of the degumming tank;

step S113: setting degumming process parameters of a degumming machine, specifically setting degumming spraying time to be 10 +/-2 min, spraying water pressure to be 0.02-0.05Mpa, water temperature to be 20-30 ℃, selecting tap water or concentrated water or recycled water as water quality, adjusting a spray pipe to enable a pipe orifice to face a partition plate when spraying, wherein the distance is 10-20mm, and carrying out mist spraying on the pipe orifice of the spray pipe in a horn mouth shape;

step S114: and after the degumming treatment is finished, taking out the silicon wafer according to the width of the partition plate, wiping four end faces and chamfer positions of the silicon wafer, and finally putting the silicon wafer into a turnover water tank.

3. The method for cleaning a large-size monocrystalline silicon wafer according to claim 1, wherein: when the first ultrasonic precleaning is performed in step S3, the cleaning time of the reagent tank is set to 220 ± 20S, the temperature is 45 ± 5 ℃, the ultrasonic intensity power is 24 ± 2KHz, the ultrasonic current is 5 ± 0.5A, and the water quality in the reagent tank is pure water.

4. The method for cleaning a large-size monocrystalline silicon wafer according to claim 1, wherein: s4-the ultrasonic alkaline washing for multiple times in the step S6 adopts a conventional double-component silicon wafer cleaning agent, and the ratio of the alkaline agent to the active agent is 2: 1;

wherein, in the initial addition, the alkaline agent is added according to 4-4.5% of the volume of the tank body of the medicament tank, and the active agent is added according to 2.0-2.25% of the volume of the tank body of the medicament tank; during ultrasonic alkaline cleaning, the cleaning time is set to be 220 +/-20 s, the temperature is 55 +/-5 ℃, the ultrasonic intensity power is 24 +/-2 KHz, the ultrasonic current is 5 +/-0.5A, and the water in the agent tank is pure water.

5. The method for cleaning a large-size monocrystalline silicon wafer according to claim 1, wherein: in step S7, when the ultrasonic precleaning is performed again, the cleaning time is set to 220 ± 20S, the temperature is set to 45 ± 5 ℃, the ultrasonic intensity power is set to 24 ± 2KHz, the ultrasonic current is set to 5 ± 0.5A, and the water quality in the agent tank is pure water.

6. The method for cleaning a large-size monocrystalline silicon wafer according to claim 1, wherein: in the step S8, hydrogen peroxide is a strong oxidant, when hydrogen peroxide is initially added, the concentration of a stock solution of hydrogen peroxide is 7-8% and is 15 +/-2% of the volume of the tank body of the medicament tank, and caustic soda flakes are 0.10-0.15% of the volume of the tank body of the medicament tank;

the cleaning time of the reagent tank is set to be 220 +/-20 s, the temperature is set to be 40 +/-5 ℃, the ultrasonic intensity power is set to be 24 +/-2 KHz, the ultrasonic current is set to be 5 +/-0.5A, and the water quality in the reagent tank is pure water.

7. The method for cleaning a large-size monocrystalline silicon wafer according to claim 1, wherein: and S9-S11, wherein the cleaning time of the medicament tank is set to be 220 +/-20S, the temperature is set to be 50 +/-5 ℃, the ultrasonic intensity power is set to be 24 +/-2 KHz, the ultrasonic current is set to be 5 +/-0.5A, and the water quality in the medicament tank is pure water.

8. The method for cleaning a large-size monocrystalline silicon wafer according to claim 1, wherein: in step S12, when the fourth-stage overflow fourth rinsing is performed, the cleaning time of the chemical tank is set to 220 ± 20S, the temperature is 55 ± 5 ℃, the ultrasonic intensity power is 24 ± 2KHz, the ultrasonic current is 5 ± 0.5A, and the water quality in the chemical tank is pure water.

9. The method for cleaning a large-size monocrystalline silicon wafer according to claim 1, wherein: in step S13, the cleaning time of the slow stripping tank is set to be 100 +/-10S, the temperature is set to be 85 +/-5 ℃, and the water in the slow stripping tank is pure water.

10. The method for cleaning a large-size monocrystalline silicon wafer according to claim 1, wherein: in step S14, the total drying time of the drying groove is set to 400 +/-20S, and the temperature is set to 95 +/-5 ℃.