Cleaning method of silicon wafer preparation device

Abstract

The invention provides a cleaning method of a silicon wafer preparation device. The cleaning method comprises the following steps: (1) injecting hydrogen peroxide and hydrochloric acid into a tank body of the silicon wafer preparation device for soaking; (2) emptying the solution in the tank body, and then cleaning the tank body with water; and (3) liquid medicine is injected into the tank body after water cleaning, the silicon wafer preparation device is made to run in an idle mode, then the liquid medicine is discharged, and cleaning is completed. According to the invention, hydrogen peroxide and hydrochloric acid are used for synergistically cleaning the tank body, so that most pollution sources can be cleaned and removed, most pollution sources are discharged out of the tank body in a water cleaning manner, and the pollution sources are further removed and discharged in an air running manner by adding liquid medicine. By the adoption of the cleaning method, the line splitting condition can be met more easily, the pollution proportion in the earlier stage of line splitting is reduced, the line splitting stability is improved, and the line splitting efficiency and the high-quality rate are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar cells and relates to a cleaning method for a silicon wafer preparation device. Background Art

[0002] With the increasingly serious energy crisis, in recent years, the development and utilization of solar energy have received more and more attention. With the continuous development and application of new technologies, the conversion efficiency of solar cells has continuously refreshed historical records. The refresh of high conversion efficiency of solar energy is inseparable from a stable process route, stable equipment, and a high-requirement preparation environment, etc.

[0003] However, after the wet bench is cleaned and the liquid is changed and the bench is maintained, different degrees of pollution will occur, and the pollution sources are not fixed. However, it is certain that it will pollute the silicon wafers, and after the pollution appears, it will greatly affect the battery efficiency.

[0004] Therefore, there is an urgent need to provide a cleaning method that can clean most of the pollution sources and discharge the pollution sources from the tank. Summary of the Invention

[0005] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a cleaning method for a silicon wafer preparation device. The present invention uses hydrogen peroxide and hydrochloric acid to jointly clean the tank, which can clean and remove most of the pollution sources, and most of the pollution sources are discharged from the tank by means of water cleaning. Then, by adding liquid medicine and running the equipment without wafers, the pollution sources are further removed and discharged. Using the cleaning method of the present invention can more easily meet the start-up conditions, reduce the pollution ratio in the early stage of start-up, improve the start-up stability, and improve the start-up efficiency and quality rate.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] The present invention provides a cleaning method for a silicon wafer preparation device, and the cleaning method includes:

[0008] (1) Inject hydrogen peroxide and hydrochloric acid into the tank of the silicon wafer preparation device for soaking;

[0009] (2) Drain the solution in the tank, and then clean the tank with water;

[0010] (3) Inject liquid medicine into the tank after water cleaning, make the silicon wafer preparation device run without wafers, and then discharge the liquid medicine, that is, the cleaning is completed.

[0011] It should be noted that the silicon wafer preparation device running without wafers means that devices such as a flower basket are placed according to the normal silicon wafer preparation process flow, but no silicon wafers are placed, and the tank runs and works according to the normal process parameters.

[0012] The present invention provides a cleaning method for a silicon wafer preparation device, which uses hydrogen peroxide and hydrochloric acid to clean the tank synergistically. Among them, hydrogen peroxide has the characteristics of strong oxidizing and reducing properties, and can remove stains, pollution sources such as lipid peroxides, etc. Hydrochloric acid has the characteristics of reducing and reacting with metals, and can remove metal ion pollution sources. With the synergistic cooperation of the two, most of the pollution sources can be cleaned and removed, and most of the pollution sources are discharged from the tank by means of water cleaning. Then, by adding the liquid medicine and running it empty, the pollution sources are further removed and discharged. Using the cleaning method of the present invention can more easily meet the start-up conditions, reduce the pollution ratio in the early stage of start-up, improve the start-up stability, and improve the start-up efficiency and quality rate.

[0013] In the present invention, before cleaning, the silicon wafer preparation device is shut down for simple sanitation cleaning.

[0014] Preferably, the mass concentration of the hydrogen peroxide is 0.4-10%, for example, it can be 0.4%, 1%, 2%, 3%, 5%, 7%, 8% or 10%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0015] Preferably, the mass concentration of the hydrochloric acid is 0.4-5%, for example, it can be 0.4%, 0.8%, 1%, 2%, 3%, 4% or 5%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0016] Preferably, the volume ratio of the hydrogen peroxide to the hydrochloric acid in step (1) is (1-5):1, for example, it can be 1:1, 2:1, 3:1, 4:1 or 5:1, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0017] Preferably, the tank of the silicon wafer preparation device includes an alkali cleaning tank, a texturing tank, an acid pickling tank and a water washing tank.

[0018] In the present invention, the alkali cleaning tank includes a strong alkali cleaning tank and a weak alkali cleaning tank. The strong alkali cleaning tank (i.e., the pre-cleaning tank), the weak alkali cleaning tank, the texturing tank and the acid pickling tank are functional tanks. The cleaning method of the present invention is used to clean the above-mentioned tanks. The number of the above-mentioned tanks can be increased or decreased according to production capacity or cleaning requirements.

[0019] Exemplarily, the tank of the silicon wafer preparation device includes a pre-cleaning tank, a water washing tank, a texturing tank, a water washing tank, a weak alkali cleaning tank, a water washing tank, an acid pickling tank, a water washing tank, a slow lift tank and a drying tank connected in sequence. Each tank can be connected in parallel and / or in series according to needs.

[0020] Preferably, in step (1), for the alkali cleaning tank and the texturing tank, the mass concentration of hydrogen peroxide is 1.5 - 10%, for example, it can be 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10%, etc., and the mass concentration of hydrochloric acid is 0.8 - 5%, for example, it can be 0.8%, 1%, 2%, 3%, 4% or 5%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0021] Preferably, in step (1), for the alkali cleaning tank and the texturing tank, the volume ratio of hydrogen peroxide to hydrochloric acid is (2 - 5):1, for example, it can be 2:1, 3:1, 4:1 or 5:1, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0022] Preferably, in step (1), for the pickling tank, the mass concentration of hydrogen peroxide is 0.8 - 5%, for example, it can be 0.8%, 1%, 2%, 3%, 4% or 5%, etc., and the mass concentration of hydrochloric acid is 0.8 - 5%, for example, it can be 0.8%, 1%, 2%, 3%, 4% or 5%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0023] Preferably, in step (1), for the pickling tank, the volume ratio of hydrogen peroxide to hydrochloric acid is (1 - 3):1, for example, it can be 1:1, 2:1 or 3:1, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0024] Preferably, in step (1), for the first water washing tank and the second water washing tank, the mass concentration of hydrogen peroxide is 0.4 - 2.5%, for example, it can be 0.4%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 2% or 2.5%, etc., and the mass concentration of hydrochloric acid is 0.4 - 2.5%, for example, it can be 0.4%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 2% or 2.5%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0025] Preferably, in step (1), for the first water washing tank and the second water washing tank, the volume ratio of hydrogen peroxide to hydrochloric acid is (1 - 3):1, for example, it can be 1:1, 2:1 or 3:1, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0026] Preferably, the liquid medicine in step (3) includes at least one of sodium hydroxide solution, hydrogen peroxide, hydrofluoric acid, hydrochloric acid, cleaning agent and water.

[0027] Preferably, for the alkali cleaning tank and the texturing tank, the liquid medicine includes at least one of sodium hydroxide solution, hydrogen peroxide, cleaning agent, hydrofluoric acid, and hydrochloric acid, and the cleaning agent includes at least one of defoamer, antioxidant, surfactant, pH regulator, complexing agent, and organic acid.

[0028] Preferably, for the alkali cleaning tank and the texturing tank, the mass concentration of the sodium hydroxide solution in the liquid medicine is 0.2 - 1.4%, for example, it can be 0.2%, 0.4%, 0.6%, 0.8%, 1%, 1.2%, or 1.4%, etc., but not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0029] Preferably, for the alkali cleaning tank and the texturing tank, the mass concentration of the hydrogen peroxide in the liquid medicine is 1 - 7%, for example, it can be 1%, 2%, 3%, 4%, 5%, 6%, or 7%, etc., but not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0030] Preferably, for the alkali cleaning tank and the texturing tank, the mass concentration of the cleaning agent in the liquid medicine is less than or equal to 0.6%, for example, it can be 0.6%, 0.5%, 0.4%, 0.3%, or 0.2%, etc., but not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0031] Preferably, for the texturing tank, the volume ratio of the sodium hydroxide solution to the cleaning agent in the liquid medicine is 4:1.

[0032] Preferably, for the pickling tank, the liquid medicine includes at least one of hydrofluoric acid, hydrochloric acid, and cleaning agent, and the cleaning agent includes at least one of defoamer, antioxidant, surfactant, PH regulator, complexing agent, and organic acid.

[0033] Preferably, for the pickling tank, the mass concentration of the hydrofluoric acid in the liquid medicine is 2 - 12%, for example, it can be 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, or 12%, etc., but not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0034] Preferably, for the pickling tank, the mass concentration of the hydrochloric acid in the liquid medicine is 2 - 16%, for example, it can be 2%, 3%, 4%, 6%, 8%, 10%, 12%, 14%, or 16%, etc., but not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0035] Preferably, for the pickling tank, the mass concentration of the cleaning agent in the liquid medicine is less than or equal to 0.6%, for example, it can be 0.6%, 0.5%, 0.4%, 0.3% or 0.2%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0036] Preferably, for the pickling tank, the volume ratio of hydrofluoric acid, hydrochloric acid and the cleaning agent in the liquid medicine is 7:9:0.3.

[0037] Preferably, for the first water washing tank and the second water washing tank, the liquid medicine includes water.

[0038] Preferably, the empty running time of the alkali cleaning tank and the texturing tank is independently 200 - 1000 s, for example, it can be 200 s, 300 s, 400 s, 500 s, 600 s, 700 s, 800 s, 900 s or 1000 s, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0039] Preferably, the empty running time of the pickling tank is 50 - 300 s, for example, it can be 50 s, 60 s, 70 s, 100 s, 150 s, 200 s, 250 s or 300 s, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0040] Preferably, the empty running time of the water washing tank is 50 - 300 s, for example, it can be 50 s, 60 s, 70 s, 100 s, 150 s, 200 s, 250 s or 300 s, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0041] As a preferred technical solution of the present invention, the cleaning method specifically includes:

[0042] (Ⅰ) Inject hydrogen peroxide and hydrochloric acid into the tank body of the silicon wafer preparation device and soak for 1 - 5 h (for example, it can be 1 h, 2 h, 3 h, 4 h, 5 h), and the tank body of the silicon wafer preparation device includes an alkali cleaning tank, a texturing tank, a pickling tank and a water washing tank;

[0043] (Ⅱ) Drain the solution in the tank body, and then wash the tank body with water 2 - 3 times (for example, it can be 1 time, 2 times or 3 times);

[0044] (Ⅲ) Inject the liquid medicine into the tank body after water washing, make the silicon wafer preparation device run empty, and then discharge the liquid medicine, thus completing the cleaning.

[0045] The numerical ranges described in the present invention include not only the above-listed point values, but also any point values between the above numerical ranges that are not listed. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the described ranges.

[0046] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0047] The present invention provides a cleaning method for a silicon wafer preparation device, which uses hydrogen peroxide and hydrochloric acid to clean the tank body synergistically. Among them, hydrogen peroxide has the characteristics of strong oxidizing and reducing properties, and can remove stains, pollution sources such as peroxidized lipids and peroxides. Hydrochloric acid has the characteristics of reducing properties and reacting with metals, and can remove metal ion pollution sources. With the synergistic cooperation of the two, most of the pollution sources can be cleaned and removed, and most of the pollution sources can be discharged from the tank body by means of water cleaning, improving the cleanliness of the tank body. Then, by adding the liquid medicine and running it empty, the pollution sources can be further removed and discharged. Using the cleaning method of the present invention can more easily meet the start-up conditions, reduce the pollution ratio in the early stage of start-up, and improve the start-up stability, start-up efficiency and quality rate. Specific embodiments

[0048] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "set", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0049] The technical solutions of the present invention will be further described below through specific embodiments.

[0050] Example 1

[0051] This example provides a silicon wafer preparation device. The tank body of the silicon wafer preparation device includes a pre-cleaning tank, a water washing tank, a texturing tank A, a texturing tank B, a water washing tank, a weak base cleaning tank, a water washing tank, an acid cleaning tank, a water washing tank, a slow lift tank and a drying tank connected in sequence. The pre-cleaning tank and the weak base cleaning tank are alkaline cleaning tanks. Baskets are provided in the tank body of the silicon wafer preparation device, and the drying tank does not need to be cleaned.

[0052] Example 2

[0053] This example provides a method for cleaning the silicon wafer preparation device of Example 1. The method includes:

[0054] (1) Inject hydrogen peroxide solution and hydrochloric acid with a mass concentration of 1.5% into the pre - cleaning tank, texturing tank, weak - base cleaning tank, pickling tank, and all the water - washing tanks respectively. For the pre - cleaning tank, texturing tank A, texturing tank B, and weak - base cleaning tank, the volume ratio of hydrogen peroxide solution to hydrochloric acid is 2:1; for the pickling tank and water - washing tanks, the volume ratio of hydrogen peroxide solution to hydrochloric acid is 1:1. Immerse each tank for 1 h.

[0055] (2) Drain the solution in the tank, and then repeatedly clean the tank with pure water 2 - 3 times.

[0056] (3) Prepare the liquid medicine according to the silicon wafer production process. The liquid medicine formula is shown in Table 1. Inject the liquid medicine into the tank after water - cleaning, and make the silicon wafer preparation device run idly. The operating parameters are shown in Table 1; then drain the liquid medicine, and the cleaning is completed.

[0057] Table 1

[0058]

[0059]

[0060] Example 3

[0061] The difference between this example and Example 2 is that in step (1), the mass concentrations of hydrogen peroxide solution and hydrochloric acid are both adjusted to 10%.

[0062] The remaining parameters are exactly the same as those in Example 2.

[0063] Example 4

[0064] The difference between this example and Example 2 is that in step (3), the idle - running time of each tank is extended, and the idle - running time of each tank is extended by 100 s.

[0065] The remaining parameters are exactly the same as those in Example 2.

[0066] Example 5

[0067] The difference between this example and Example 2 is that in step (1), the mass concentrations of hydrogen peroxide solution and hydrochloric acid are both adjusted to 10%, and at the same time in step (3), the idle - running time of each tank is extended, and the idle - running time is extended by 100 s.

[0068] The remaining parameters are exactly the same as those in Example 2.

[0069] Example 6

[0070] The difference between this embodiment and Embodiment 2 is that in step (1), the pickling tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 0.8% each, and the rinsing tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 0.4% each; meanwhile, in step (3), the empty running time of each tank is extended, and the empty running time is extended by 100 s for all tanks.

[0071] The remaining parameters are exactly the same as those in Embodiment 2.

[0072] Embodiment 7

[0073] The difference between this embodiment and Embodiment 2 is that in step (1), the pickling tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 5% each, and the rinsing tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 0.4% each; meanwhile, in step (3), the empty running time of each tank is extended, and the empty running time is extended by 100 s for all tanks.

[0074] The remaining parameters are exactly the same as those in Embodiment 2.

[0075] Embodiment 8

[0076] The difference between this embodiment and Embodiment 2 is that in step (1), the pickling tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 0.8% each, and the rinsing tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 5% each; meanwhile, in step (3), the empty running time of each tank is extended, and the empty running time is extended by 100 s for all tanks.

[0077] The remaining parameters are exactly the same as those in Embodiment 2.

[0078] Embodiment 9

[0079] The difference between this embodiment and Embodiment 2 is that in step (1), the pickling tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 0.8% each, and the rinsing tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 0.4% each; meanwhile, in step (3), the empty running time of each tank is extended, and the empty running time is extended by 200 s for all tanks.

[0080] The remaining parameters are exactly the same as those in Embodiment 2.

[0081] Embodiment 10

[0082] The difference between this embodiment and Embodiment 2 is that in step (1), the pickling tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 0.8% each, and the rinsing tank is soaked with hydrogen peroxide and hydrochloric acid with a mass concentration of 0.4% each; meanwhile, in step (3), the empty running time of each tank is extended, and the empty running time is extended by 130 s for all tanks.

[0083] The remaining parameters are exactly the same as those in Embodiment 2.

[0084] Embodiment 11

[0085] The difference between this embodiment and Embodiment 6 is that for the pre - cleaning tank, the texturing tank A, the texturing tank B, and the weak - alkali cleaning tank, the volume ratio of hydrogen peroxide to hydrochloric acid is adjusted to 0.5:1.

[0086] The remaining parameters are exactly the same as those in Embodiment 6.

[0087] Embodiment 12

[0088] The difference between this embodiment and Embodiment 6 is that for the pre - cleaning tank, the texturing tank A, the texturing tank B, and the weak - alkali cleaning tank, the volume ratio of hydrogen peroxide to hydrochloric acid is adjusted to 3:1.

[0089] The remaining parameters are exactly the same as those in Embodiment 6.

[0090] Comparative Example 1

[0091] The difference between this comparative example and Embodiment 2 is that in step (1), only hydrogen peroxide is used for soaking.

[0092] The remaining parameters are exactly the same as those in Embodiment 2.

[0093] Comparative Example 2

[0094] The difference between this comparative example and Comparative Example 1 is that in step (1), the mass concentration of hydrogen peroxide is adjusted to 10%.

[0095] The remaining parameters are exactly the same as those in Comparative Example 1.

[0096] Comparative Example 3

[0097] The difference between this comparative example and Embodiment 2 is that in step (1), only hydrochloric acid is used for soaking.

[0098] The remaining parameters are exactly the same as those in Embodiment 2.

[0099] Comparative Example 4

[0100] The difference between this comparative example and Comparative Example 3 is that in step (1), the mass concentration of hydrochloric acid is adjusted to 10%.

[0101] The remaining parameters are exactly the same as those in Comparative Example 3.

[0102] Comparative Example 5

[0103] This comparative example provides a method for cleaning the silicon - wafer preparation device of Embodiment 1, that is, using pure water to repeatedly clean each tank.

[0104] Performance Test

[0105] Using the silicon - wafer preparation device cleaned by the above - mentioned embodiments and comparative examples, trial - produce silicon wafers and detect whether there are pollution sources, specifically including:

[0106] 1) Produce 20 silicon wafers according to the formula and operating parameters in Table 1.

[0107] 2) After the process is completed, the photoluminescence imaging of the silicon wafer is tested using a PL tester to confirm whether there is a contamination source based on the image.

[0108] The test results are shown in Table 2.

[0109] Table 2

[0110]

[0111]

[0112] analyze:

[0113] (1) According to the test results in Table 2, Examples 2-10 and 12 can meet the expected requirements, effectively remove the pollution source in the tank body, and improve the cleanliness of the tank body. However, Examples 2 and 3 are unstable.

[0114] (2) Considering the production cost, Example 6 is relatively good; if time is sufficient, Example 10 can also be considered. The idle running time is long and the effect is correspondingly better guaranteed, but the cleaning time is longer.

[0115] (3) According to the test results of Examples 2-10, the use of a mixture of hydrogen peroxide and hydrochloric acid with concentrations of 1.5%-10% and 0.8%-5%, respectively, has the best effect on cleaning the tank body pollution source. Although the decontamination ability will increase as the concentration increases, considering the acid resistance of the tank body and accessories, it is better to use a low concentration. After the tank body is cleaned, the idle running time increases, and the pollutants carried away also increase accordingly. The better the cleanliness, the longer the cleaning time will be.

[0116] (4) According to the test results of Example 6 and Examples 11-12, if the volume ratio of hydrogen peroxide to hydrochloric acid is too small, the decontamination ability will be insufficient and there will be a risk of pollution; if the volume ratio of hydrogen peroxide to hydrochloric acid is too large, the decontamination ability is better, but it will lead to a waste of hydrogen peroxide.

[0117] (5) According to the test results of Example 2 and Comparative Examples 1-5, if hydrogen peroxide and hydrochloric acid are not used in combination for soaking, or only clean water is used for cleaning, even if the concentration is increased, the pollution source cannot be completely removed, resulting in dark silicon wafers.

[0118] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A cleaning method for a silicon wafer preparation device, characterized in that, the cleaning method includes: (1) Inject hydrogen peroxide and hydrochloric acid into the tank of the silicon wafer preparation device for soaking; (2) Drain the solution in the tank, and then wash the tank with water; (3) Inject the liquid medicine into the tank after water washing, make the silicon wafer preparation device run empty, and then drain the liquid medicine, thus completing the cleaning.

2. The cleaning method according to claim 1, characterized in that, in step (1), the mass concentration of the hydrogen peroxide is 0.4 - 10%; Preferably, in step (1), the mass concentration of the hydrochloric acid is 0.4 - 5%; Preferably, in step (1), the volume ratio of the hydrogen peroxide to the hydrochloric acid is (1 - 5):

1.

3. The cleaning method according to claim 1 or 2, characterized in that, the tank of the silicon wafer preparation device includes an alkali cleaning tank, a texturing tank, an acid pickling tank and a water washing tank.

4. The cleaning method according to claim 3, characterized in that, in step (1), for the alkali cleaning tank and the texturing tank, the mass concentration of the hydrogen peroxide is 1.5 - 10%, and the mass concentration of the hydrochloric acid is 0.8 - 5%; Preferably, in step (1), for the alkali cleaning tank and the texturing tank, the volume ratio of the hydrogen peroxide to the hydrochloric acid is (2 - 5):1; Preferably, in step (1), for the acid pickling tank, the mass concentration of the hydrogen peroxide is 0.8 - 5%, and the mass concentration of the hydrochloric acid is 0.8 - 5%; Preferably, in step (1), for the acid pickling tank, the volume ratio of the hydrogen peroxide to the hydrochloric acid is (1 - 3):1; Preferably, in step (1), for the water washing tank, the mass concentration of the hydrogen peroxide is 0.4 - 2.5%, and the mass concentration of the hydrochloric acid is 0.4 - 2.5%; Preferably, in step (1), for the water washing tank, the volume ratio of the hydrogen peroxide to the hydrochloric acid is (1 - 3):

1.

5. The cleaning method according to any one of claims 1 - 4, characterized in that, the liquid medicine in step (3) includes at least one of sodium hydroxide solution, hydrogen peroxide, hydrofluoric acid, hydrochloric acid, cleaning agent and water.

6. The cleaning method according to any one of claims 3 - 5, characterized in that, for the alkali cleaning tank and the texturing tank, the liquid medicine includes at least one of sodium hydroxide solution, hydrogen peroxide, cleaning agent, hydrofluoric acid and hydrochloric acid, and the cleaning agent includes at least one of defoamer, antioxidant, surfactant, pH regulator, complexing agent and organic acid; Preferably, for the alkali cleaning tank and the texturing tank, the mass concentration of the sodium hydroxide solution in the liquid medicine is 0.2 - 1.4%; Preferably, for the alkali cleaning tank and the texturing tank, the mass concentration of the hydrogen peroxide in the liquid medicine is 1 - 7%; Preferably, for the alkali cleaning tank and the texturing tank, the mass concentration of the cleaning agent in the liquid medicine is less than or equal to 0.6%.

7. The cleaning method according to any one of claims 3 - 6, characterized in that, for the acid pickling tank, the liquid medicine includes at least one of hydrofluoric acid, hydrochloric acid and cleaning agent, and the cleaning agent includes at least one of defoamer, antioxidant, surfactant, PH regulator, complexing agent and organic acid; Preferably, for the pickling tank, the mass concentration of hydrofluoric acid in the liquid medicine is 2-12%; Preferably, for the pickling tank, the mass concentration of hydrochloric acid in the liquid medicine is 2-16%; Preferably, for the pickling tank, the mass concentration of the cleaning agent in the liquid medicine is less than or equal to 0.6%.

8. The cleaning method according to any one of claims 3-7, characterized in that for the water washing tank, the liquid medicine comprises water.

9. The cleaning method according to any one of claims 3-8, characterized in that the empty running time of the alkali cleaning tank and the texturing tank is independently 200-1000 s; Preferably, the empty running time of the pickling tank is 50-300 s; Preferably, the empty running time of the water washing tank is independently 50-300 s.

10. The cleaning method according to any one of claims 3-9, characterized in that the cleaning method specifically comprises: (Ⅰ) Inject hydrogen peroxide and hydrochloric acid into the tank body of the silicon wafer preparation device and soak for 1-5 h. The tank body of the silicon wafer preparation device comprises an alkali cleaning tank, a texturing tank, a pickling tank and a water washing tank; (Ⅱ) Drain the solution in the tank body, and then wash the tank body with water 2-3 times; (Ⅲ) Inject the liquid medicine into the tank body after water washing, make the silicon wafer preparation device run empty, and then discharge the liquid medicine, thus completing the cleaning.

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