A method for processing LPCVD boat support for Topcon battery and quartz boat support for Topcon battery

Abstract

The present invention provides a method for treating an LPCVD boat support for a Topcon battery and a quartz boat support for a Topcon battery. The method comprises the following steps: introducing H2 into the LPCVD boat support for a first saturation treatment, and then introducing a mixed gas of H2 and N2O for a second saturation treatment to obtain a saturated LPCVD boat support. The present invention can effectively remove fine contamination from the LPCVD boat support and reduce contamination to the small boat by first introducing H2 into the LPCVD boat support for saturation treatment, and then introducing a mixed gas of H2 and N2O for saturation treatment, thereby achieving the purpose of improving the cleanliness of the furnace tube, thereby further improving the battery yield and conversion efficiency. In addition, the saturation treatment method does not require the introduction of an oxidizing gas, can reduce the total amount of gas used in the saturation treatment and the number of saturation treatments, significantly reduce the treatment temperature, and extend the service life of the quartz boat support.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a method for processing an LPCVD boat support for a Topcon cell and a quartz boat support for a Topcon cell. Background Art

[0002] TOPCon cells (Tunnel Oxide Passivating Contacts) are a type of solar cell based on the principle of selective carriers. The contacts are passivated through the tunnel oxide layer, and the unit structure is an N-type silicon substrate unit. An ultra-thin silicon oxide layer is prepared on the back of the cell, and then a thin doped silicon layer is deposited. The two layers together form a passive contact structure, which effectively reduces surface recombination and metal contact recombination. In the preparation process of Topcon cells, silicon wafers usually need to go through processes such as texturing, diffusion, etching, coating or printing in sequence. A wafer carrier tool for carrying silicon wafers is required in a process furnace (such as a diffusion furnace or a deposition furnace). The quartz boat is a commonly used wafer carrier tool. Multiple quartz boats are placed on a quartz boat support, and the boat body carrying the silicon wafers is lifted by the quartz boat to deliver the silicon wafers into the process furnace.

[0003] However, after long-term use, Topcon battery LPCVD boat supports will be polluted by deposited dust, debris, etc., causing manufacturing abnormalities and a decrease in battery conversion efficiency. This often requires cleaning to ensure the cleanliness of its surface, thereby reducing the damage to its performance or use caused by impurities attached to it, and facilitating its subsequent use or further processing.

[0004] However, there are generally few dedicated methods for LPCVD boat supports in the prior art. Most methods use the quartz boat body to be cleaned to treat the boat support. The existing quartz boat cleaning and saturation process is generally: first, the quartz boat is immersed in acid pickling-water washing-purging, and then nitrogen, oxygen, phosphorus oxychloride, or a combination of these three gases are introduced into the diffusion furnace for saturation treatment. In this way, acid pickling generally requires a higher concentration of hydrofluoric acid, but the pickling solution has strong etching properties, and the degree of cleaning is difficult to control. It is easy to wash away part of the quartz, which will cause the boat teeth of the quartz boat to become thinner due to corrosion, reducing the service life of the quartz boat; and the use of oxygen and phosphorus oxychloride will produce phosphorus pentoxide during the saturation process, which is easy to remain in the boat support, and the saturation effect of using only nitrogen is poor, which is not suitable for cleaning the boat support. It is difficult to clean the fine dirt deposited in the boat support, and there are defects such as poor appearance, appearance or imprints, too high processing temperature, and repeated saturation treatment.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] One of the purposes of the present invention is to provide a method for Topcon battery processing LPCVD boat support. The method of the present invention is to first pass H 2 Saturation treatment was performed, and H 2 and N 2 The saturation treatment of the mixed gas of O can remove dirt on the surface of the boat support and improve the battery yield.

[0007] A second object of the present invention is to provide a quartz boat support for a Topcon battery, wherein the quartz boat support for a Topcon battery is obtained by processing the LPCVD boat support method for a Topcon battery as described above.

[0008] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0009] In a first aspect, the present invention provides a method for processing a LPCVD boat support with a Topcon battery, the method comprising the following steps:

[0010] Feed H into the LPCVD vessel 2 Perform the first saturation treatment and then introduce H 2 and N 2 O mixed gas is subjected to a second saturation treatment to obtain a saturated LPCVD boat support.

[0011] In the present invention, H is first introduced into the LPCVD boat support. 2 Saturation treatment was performed, and H 2 and N 2 The method of saturation treatment with mixed gas of O can effectively remove fine contamination on the LPCVD boat support, reduce pollution to the boat, and achieve the purpose of improving the cleanliness of the furnace tube, thereby further improving the battery yield and conversion efficiency. In addition, this saturation treatment method does not require the introduction of oxidizing gas, which can reduce the total amount of gas used in the saturation treatment and the number of saturation treatments, and significantly reduce the treatment temperature; and this method can further reduce the amount of acid used in the early pickling process to reduce corrosion to the quartz boat support and extend the service life of the quartz boat support.

[0012] Preferably, the temperature of the first saturation treatment is 600-780°C, for example, it can be 600°C, 610°C, 620°C, 630°C, 640°C, 650°C, 660°C, 670°C, 680°C, 690°C, 700°C, 750°C, 780°C, etc.

[0013] Preferably, the time of the first saturation treatment is 30 to 60 min, for example, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, etc.

[0014] Preferably, the pressure of the first saturation treatment is 120-200 torr, for example, it can be 120 torr, 130 torr, 140 torr, 150 torr, 160 torr, 170 torr, 180 torr, 190 torr, 200 torr, etc.

[0015] Preferably, in the first saturation treatment, H 2 The gas flow rate is 22 to 32 slm, for example, it can be 22 slm, 23 slm, 24 slm, 25 slm, 26 slm, 27 slm, 28 slm, 29 slm, 30 slm, 31 slm, 32 slm, etc.

[0016] In the present invention, by adjusting the temperature, time, pressure, and H 2 The optimization of gas flow can further improve the saturation treatment effect.

[0017] Preferably, the temperature of the second saturation treatment is 500-600°C, for example, it can be 500°C, 510°C, 520°C, 530°C, 540°C, 550°C, 560°C, 570°C, 580°C, 590°C, 600°C, etc.

[0018] Preferably, the time of the second saturation treatment is 60 to 90 min, for example, it can be 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min, etc.

[0019] Preferably, the pressure of the second saturation treatment is 320-420 torr, for example, it can be 320 torr, 330 torr, 340 torr, 350 torr, 360 torr, 370 torr, 380 torr, 390 torr, 400 torr, 410 torr, 420 torr, etc.

[0020] Preferably, the total flow rate of the mixed gas in the second saturation treatment is 8 to 40 slm, for example, it can be 8 slm, 9 slm, 10 slm, 11 slm, 12 slm, 13 slm, 14 slm, 15 slm, 16 slm, 17 slm, 18 slm, 19 slm, 20 slm, 25 slm, 30 slm, 35 slm, 40 slm, etc.

[0021] Preferably, H 2 and N 2 The flow ratio of O is 1:(4-9), for example, it can be 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, etc.

[0022] Preferably, the H 2 The flow rate is 1.6~4slm, for example, it can be 1.6slm, 1.8slm, 2slm, 2.2slm, 2.4slm, 2.6slm, 2.8slm, 3slm, 3.2slm, 3.4slm, 3.6slm, 3.8slm, 4slm, etc.

[0023] Preferably, the N 2 The flow rate of O is 6.4 to 36 slm, for example, it can be 6.4 slm, 7 slm, 8 slm, 10 slm, 12 slm, 14 slm, 16 slm, 18 slm, 20 slm, 22 slm, 24 slm, 26 slm, 28 slm, 30 slm, 32 slm, 34 slm, 36 slm, etc.

[0024] In the present invention, the temperature, time, pressure, mixed gas flow rate, H 2 and N 2 The optimization of the flow rate ratio of O can further achieve the purpose of improving the saturation treatment effect.

[0025] Preferably, when H is introduced 2 Before the first saturation treatment, the following pre-treatment steps are also included:

[0026] The LPCVD boat support is pickled using a mixed acid solution;

[0027] Perform water washing on the LPCVD boat support after pickling;

[0028] The LPCVD boat support is purged after water washing.

[0029] In the present invention, the following specific acid-washing-water-purging pretreatment steps are adopted to better remove the contamination of the LPCVD boat support, reduce the contamination of the quartz boat, improve the cleanliness of the furnace tube, and improve the battery yield and conversion efficiency.

[0030] Preferably, the mixed acid solution comprises the following components by mass percentage:

[0031] 0.1-1% hydrogen chloride, 0.05-1% hydrogen fluoride, 0-0.5% oxidant, 0-0.2% complexing agent, 0-0.2% surfactant, and the balance is water.

[0032] Taking the mass of the mixed acid solution as 100%, the content of hydrogen chloride is 0.1-1%, for example, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 1%, etc.

[0033] Taking the mass of the mixed acid solution as 100%, the content of hydrogen fluoride is 0.05-1%, for example, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 1%, etc.

[0034] Taking the mass of the mixed acid solution as 100%, the content of the oxidant is 0-0.5%, for example, it can be 0%, 0.01%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, etc.

[0035] Taking the mass of the mixed acid solution as 100%, the content of the complexing agent is 0-0.2%, for example, 0%, 0.01%, 0.05%, 0.1%, 0.15%, 0.2%, etc.

[0036] Taking the mass of the mixed acid solution as 100%, the content of the surfactant is 0-0.2%, for example, 0%, 0.01%, 0.05%, 0.1%, 0.15%, 0.2%, etc.

[0037] Preferably, the oxidant is selected from any one of hydrogen peroxide, peracetic acid or ammonium persulfate, or a combination of at least two thereof.

[0038] Preferably, the complexing agent is selected from any one of ethylenediaminetetraacetic acid, hydroxyethyliminodiacetic acid, hydroxyethylethylenediaminetriacetic acid, diethyltriaminepentaacetic acid or triethyltetraaminehexaacetic acid, or a combination of at least two thereof, preferably a combination of ethylenediaminetetraacetic acid and hydroxyethyliminodiacetic acid, or a combination of ethylenediaminetetraacetic acid and hydroxyethylethylenediaminetriacetic acid.

[0039] Preferably, the surfactant is selected from any one of palmitoleic acid, coconut oleic acid, polyethylene glycol, alkylphenol polyoxyethylene ether or fatty alcohol polyoxyethylene ether, or a combination of at least two thereof, preferably a combination of palmitoleic acid and polyethylene glycol, or a combination of coconut oleic acid and polyethylene glycol.

[0040] Preferably, the polyethylene glycol is selected from any one of polyethylene glycol 200, polyethylene glycol 400 or polyethylene glycol 600, or a combination of at least two thereof.

[0041] Preferably, the specific steps of the pickling treatment are: firstly placing the LPCVD boat in the mixed acid solution for static soaking, and then performing ultrasonic rinsing.

[0042] Preferably, the temperature of the static soaking is 10-30°C, for example, 10°C, 15°C, 20°C, 25°C, 30°C, etc., and the time of the static soaking is 20-40min, for example, 20min, 25min, 30min, 35min, 40min, etc.

[0043] Preferably, the temperature of the ultrasonic rinsing is 30-40°C, for example, it can be 30°C, 32°C, 34°C, 36°C, 38°C, 40°C, etc., the frequency of the ultrasonic rinsing is 30-40kHz, for example, it can be 30kHz, 32kHz, 34kHz, 36kHz, 38kHz, 40kHz, etc., and the time of the ultrasonic rinsing is 30-60min, for example, it can be 30min, 35min, 40min, 45min, 50min, 55min, 60min, etc.

[0044] Preferably, the specific steps of the water washing treatment are: firstly placing the LPCVD boat after the acid washing treatment in pure water for static soaking, and then spraying and rinsing.

[0045] Preferably, the temperature of the static soaking is 10-20°C, for example, it can be 10°C, 12°C, 14°C, 16°C, 18°C, 20°C, etc., and the time of the static soaking is 10-30min, for example, it can be 10min, 12min, 14min, 16min, 18min, 20min, 22min, 24min, 26min, 28min, 30min, etc.

[0046] Preferably, the temperature of the spray rinsing is 10-20°C, for example, 10°C, 12°C, 14°C, 16°C, 18°C, 20°C, etc., and the flow rate of the spray rinsing is 5-15m 3 / h, for example, 5m 3 / h、6m 3 / h、8m 3 / h、10m 3 / h、12m 3 / h、14m 3 / h、15m 3 / h, etc., and the spray rinsing time is 30 to 90 min, for example, it can be 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min, etc.

[0047] Preferably, the gas used for purging is nitrogen, and the flow rate of the gas is 1 to 6 m / s, for example, 1 m / s, 2 m / s, 3 m / s, 4 m / s, 5 m / s, 6 m / s, etc., and the purging time is 5 to 15 min, for example, 5 min, 6 min, 8 min, 10 min, 12 min, 14 min, 15 min, etc.

[0048] In a second aspect, the present invention provides a quartz boat support for a Topcon battery, wherein the quartz boat support for a Topcon battery is obtained by processing the method for processing an LPCVD boat support for a Topcon battery described in the first aspect.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] (1) The method used in the present invention reduces the total amount of gas used in the saturation treatment and the number of saturation treatments, and significantly reduces the saturation treatment temperature; and this method can further reduce the amount of acid used in the initial pickling process to reduce corrosion to the quartz boat support and extend the service life of the quartz boat support.

[0051] (2) The present invention adopts a specific acid-wash-water-purge pretreatment step to better remove contamination from the LPCVD boat support, reduce contamination to the quartz boat, improve the cleanliness of the furnace tube, and improve the battery yield and conversion efficiency. DETAILED DESCRIPTION

[0052] Unless otherwise defined herein, scientific and technical terms used in conjunction with the present invention shall have the meanings commonly understood by those of ordinary skill in the art. The meaning and scope of the terms should be clear, however, in the case of any potential ambiguity, the definitions provided herein take precedence over any dictionary or external definitions. In this application, unless otherwise stated, the use of "or" means "and / or". In addition, the use of the term "including" and other forms is non-limiting.

[0053] It should be noted that specific details are described in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in a variety of other ways different from those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0054] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] The present invention is further described below by way of examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or directly purchased from the market.

[0056] Example 1

[0057] This embodiment provides a method for Topcon battery processing LPCVD boat support, the method comprising the following steps:

[0058] S1. Pickling treatment

[0059] First, place the LPCVD boat in the mixed acid solution, soak it at 20°C for 30 minutes, then turn on the ultrasonic device, and perform ultrasonic rinsing at 35°C for 45 minutes at a frequency of 35kHz; wherein the mixed acid solution includes, by mass percentage, 0.5% hydrogen chloride, 0.5% hydrogen fluoride, 0.2% peracetic acid, 0.1% ethylenediaminetetraacetic acid, 0.1% hydroxyethyliminediacetic acid, 0.1% palmitic acid, 0.1% polyethylene glycol-200, and the balance is water.

[0060] S2. Water washing

[0061] The boat treated with S1 was placed in pure water and allowed to soak for 20 min at 15 °C. Then the spray device was turned on at 10 m 3 / h flow rate at 15 ℃ spray rinse for 45min.

[0062] S3, purge treatment

[0063] The S2-treated boat support was taken out of the pure water and purged with nitrogen at a flow rate of 3 m / s for 10 min.

[0064] S4, first saturation processing

[0065] Pass H into the S3 treated boat support 2 The first saturation treatment was performed at a temperature of 680°C, a time of 40 min, a pressure of 160 torr, and a H 2 The gas flow rate is 26slm.

[0066] S5, second saturation treatment

[0067] Pass H into the S4 treated boat support 2 and N 2 The second saturation treatment was carried out at a temperature of 580°C, a time of 80 min, a pressure of 360 torr, and a H 2 The gas flow rate is 3slm, N 2 The gas flow rate of O is 21 slm.

[0068] Example 2

[0069] This embodiment provides a method for Topcon battery processing LPCVD boat support, the method comprising the following steps:

[0070] S1. Pickling treatment

[0071] First, place the LPCVD boat in the mixed acid solution, soak it at 25°C for 25 minutes, then turn on the ultrasonic device, and perform ultrasonic rinsing at a frequency of 32kHz at 32°C for 50 minutes; wherein the mixed acid solution includes, by mass percentage, 0.4% hydrogen chloride, 0.6% hydrogen fluoride, 0.2% peracetic acid, 0.1% ethylenediaminetetraacetic acid, 0.1% hydroxyethylethylenediaminetriacetic acid, 0.1% coconut oil acid, 0.1% polyethylene glycol-400, and the balance is water.

[0072] S2. Water washing

[0073] The boat treated with S1 was placed in pure water and allowed to soak for 10 min at 20 °C. Then the spray device was turned on at 15 m 3 / h flow rate at 20 ℃ spray rinse for 30min.

[0074] S3, purge treatment

[0075] The S2-treated boat support was taken out of the pure water and purged with nitrogen at a flow rate of 3 m / s for 10 min.

[0076] S4, first saturation processing

[0077] Pass H into the S3 treated boat support 2 The first saturation treatment was performed at a temperature of 650°C, a time of 50 min, a pressure of 150 torr, and a H 2 The gas flow rate is 25slm.

[0078] S5, second saturation treatment

[0079] Pass H into the S4 treated boat support 2 and N 2 The second saturation treatment was carried out at a temperature of 550°C, a time of 75 min, a pressure of 350 torr, and a H 2 The gas flow rate is 1.6slm, N 2 The gas flow rate of O is 6.4 slm.

[0080] Example 3

[0081] This embodiment provides a method for Topcon battery processing LPCVD boat support, the method comprising the following steps:

[0082] S1. Pickling treatment

[0083] First, place the LPCVD boat in the mixed acid solution, soak it at 15°C for 35 minutes, then turn on the ultrasonic device, and perform ultrasonic rinsing at 37°C for 35 minutes at a frequency of 37kHz; wherein the mixed acid solution includes, by mass percentage, 0.6% hydrogen chloride, 0.4% hydrogen fluoride, 0.2% peracetic acid, 0.1% ethylenediaminetetraacetic acid, 0.1% hydroxyethyliminediacetic acid, 0.1% palmitic acid, 0.1% polyethylene glycol-600, and the balance is water.

[0084] S2. Water washing

[0085] The boat treated with S1 was placed in pure water and allowed to soak for 25 min at 10 °C. Then the spray device was turned on at 12 m 3 / h flow rate at 10 ℃ spray rinse for 75min.

[0086] S3, purge treatment

[0087] The S2-treated boat support was taken out of the pure water and purged with nitrogen at a flow rate of 3 m / s for 10 min.

[0088] S4, first saturation processing

[0089] Pass H into the S3 treated boat support 2 The first saturation treatment was carried out at a temperature of 720°C, a time of 32 min, a pressure of 180 torr, and a H 2 The gas flow rate is 22slm.

[0090] S5, second saturation treatment

[0091] Pass H into the S4 treated boat support 2 and N 2 The second saturation treatment was carried out at a temperature of 520°C, a time of 80 min, a pressure of 320 torr, and a H 2 The gas flow rate is 2slm, N 2 The gas flow rate of O is 16 slm.

[0092] Example 4

[0093] This embodiment provides a method for processing LPCVD boat supports for Topcon batteries, which differs from Embodiment 1 only in that, in S1, the mixed acid solution comprises, by mass percentage, 0.5% hydrogen chloride, 0.5% hydrogen fluoride, and the remainder is water; the other steps are exactly the same as Embodiment 1.

[0094] Example 5

[0095] This embodiment provides a method for treating LPCVD boat supports with Topcon batteries, which differs from Embodiment 1 only in that, in S1, the mixed acid solution comprises, by mass percentage, 0.5% hydrogen chloride, 0.2% hydrogen peroxide, 0.2% ethylenediaminetetraacetic acid, 0.2% palmitic acid, and the balance is water; the other steps are exactly the same as Embodiment 1.

[0096] Example 6

[0097] This embodiment provides a method for treating LPCVD boat supports with a Topcon battery, which differs from Embodiment 1 only in that, in S1, the mixed acid solution comprises, by mass percentage, 0.5% hydrogen chloride, 0.2% ammonium persulfate, 0.2% hydroxyethyliminediacetic acid, 0.2% polyethylene glycol-200, and the remainder is water; the other steps are exactly the same as Embodiment 1.

[0098] Example 7

[0099] This embodiment provides a method for Topcon battery processing LPCVD boat support, which is different from the embodiment 1 only in that in S5, the H 2 The gas flow rate is 12slm, N 2 The gas flow rate of O is 12 slm; the other steps are exactly the same as those in Example 1.

[0100] Example 8

[0101] This embodiment provides a method for Topcon battery processing LPCVD boat support, which is different from the embodiment 1 only in that in S5, the H 2 The gas flow rate is 3slm, N 2 The gas flow rate of O is 30 slm; the other steps are exactly the same as those in Example 1.

[0102] Comparative Example 1

[0103] This embodiment provides a method for Topcon battery processing LPCVD boat support, the method comprising the following steps:

[0104] S1. Pickling treatment

[0105] First, place the LPCVD boat in the mixed acid solution, soak it at 20°C for 30 minutes, then turn on the ultrasonic device, and perform ultrasonic rinsing at 35°C for 45 minutes at a frequency of 35kHz; wherein the mixed acid solution includes, by mass percentage, 0.5% hydrogen chloride, 0.5% hydrogen fluoride, 0.2% peracetic acid, 0.1% ethylenediaminetetraacetic acid, 0.1% hydroxyethyliminediacetic acid, 0.1% palmitic acid, 0.1% polyethylene glycol-200, and the balance is water.

[0106] S2. Water washing

[0107] The boat treated with S1 was placed in pure water and allowed to soak for 20 min at 15 °C. Then the spray device was turned on at 10 m 3 / h flow rate at 15 ℃ spray rinse for 45min.

[0108] S3, purge treatment

[0109] The S2-treated boat support was taken out of the pure water and purged with nitrogen at a flow rate of 3 m / s for 10 min.

[0110] S4, saturation processing

[0111] Pass H into the S3 treated boat support 2 Saturation treatment was performed; wherein the saturation treatment temperature was 680°C, the time was 120 min, the pressure was 360 torr, H 2 The gas flow rate is 26slm.

[0112] Comparative Example 2

[0113] This embodiment provides a method for Topcon battery processing LPCVD boat support, the method comprising the following steps:

[0114] S1. Pickling treatment

[0115] First, place the LPCVD boat in the mixed acid solution, soak it at 20°C for 30 minutes, then turn on the ultrasonic device, and perform ultrasonic rinsing at 35°C for 45 minutes at a frequency of 35kHz; wherein the mixed acid solution includes, by mass percentage, 0.5% hydrogen chloride, 0.5% hydrogen fluoride, 0.2% peracetic acid, 0.1% ethylenediaminetetraacetic acid, 0.1% hydroxyethyliminediacetic acid, 0.1% palmitic acid, 0.1% polyethylene glycol-200, and the balance is water.

[0116] S2. Water washing

[0117] The boat treated with S1 was placed in pure water and allowed to soak for 20 min at 15 °C. Then the spray device was turned on at 10 m 3 / h flow rate at 15 ℃ spray rinse for 45min.

[0118] S3, purge treatment

[0119] The S2-treated boat support was taken out of the pure water and purged with nitrogen at a flow rate of 3 m / s for 10 min.

[0120] S4, saturation processing

[0121] Pass H into the S4 treated boat support 2 and N 2 The saturation treatment was carried out at a temperature of 680°C, a time of 120 min, a pressure of 360 torr, and a H 2 The gas flow rate is 3slm, N 2 The gas flow rate of O is 21 slm.

[0122] Comparative Example 3

[0123] This comparative example provides a method for Topcon battery processing LPCVD boat support, the method comprising the following steps:

[0124] S1. Pickling treatment

[0125] First, place the LPCVD boat in the mixed acid solution, soak it at 20°C for 30 minutes, then turn on the ultrasonic device, and perform ultrasonic rinsing at 35°C for 45 minutes at a frequency of 35kHz; wherein the mixed acid solution includes, by mass percentage, 0.5% hydrogen chloride, 0.5% hydrogen fluoride, 0.2% peracetic acid, 0.1% ethylenediaminetetraacetic acid, 0.1% hydroxyethyliminediacetic acid, 0.1% palmitic acid, 0.1% polyethylene glycol-200, and the balance is water.

[0126] S2. Water washing

[0127] The boat treated with S1 was placed in pure water and allowed to soak for 20 min at 15 °C. Then the spray device was turned on at 10 m 3 / h flow rate at 15 ℃ spray rinse for 45min.

[0128] S3, purge treatment

[0129] The S2-treated boat support was taken out of the pure water and purged with nitrogen at a flow rate of 3 m / s for 10 min.

[0130] S4, first saturation processing

[0131] Pass H into the S3 treated boat support 2The first saturation treatment was performed at a temperature of 680°C, a time of 40 min, a pressure of 160 torr, and a H 2 The gas flow rate is 26slm.

[0132] S5, second saturation treatment

[0133] Pass H into the S4 treated boat support 2 The second saturation treatment was carried out at a temperature of 580°C, a time of 80 min, a pressure of 360 torr, and a H 2 The gas flow rate is 24slm.

[0134] Comparative Example 4

[0135] This embodiment provides a method for Topcon battery processing LPCVD boat support, the method comprising the following steps:

[0136] S1. Pickling treatment

[0137] First, place the LPCVD boat in the mixed acid solution, soak it at 20°C for 30 minutes, then turn on the ultrasonic device, and perform ultrasonic rinsing at 35°C for 45 minutes at a frequency of 35kHz; wherein the mixed acid solution includes, by mass percentage, 0.5% hydrogen chloride, 0.5% hydrogen fluoride, 0.2% peracetic acid, 0.1% ethylenediaminetetraacetic acid, 0.1% hydroxyethyliminediacetic acid, 0.1% palmitic acid, 0.1% polyethylene glycol-200, and the balance is water.

[0138] S2. Water washing

[0139] The boat treated with S1 was placed in pure water and allowed to soak for 20 min at 15 °C. Then the spray device was turned on at 10 m 3 / h flow rate at 15 ℃ spray rinse for 45min.

[0140] S3, purge treatment

[0141] The S2-treated boat support was taken out of the pure water and purged with nitrogen at a flow rate of 3 m / s for 10 min.

[0142] S4, first saturation processing

[0143] Pass H into the S3 treated boat support 2 The first saturation treatment was performed at a temperature of 680°C, a time of 40 min, a pressure of 160 torr, and a H 2 The gas flow rate is 26slm.

[0144] S5, second saturation treatment

[0145] N is introduced into the boat support after S4 treatment 2 O for the second saturation treatment; the temperature of the second saturation treatment is 580 ° C, the time is 80 min, the pressure is 360 torr, N 2 The gas flow rate of O is 24 slm.

[0146] Test Case

[0147] Test samples: LPCVD boat supports treated by the methods of Examples 1 to 8, and LPCVD boat supports treated by the methods of Comparative Examples 1 to 4;

[0148] Test items:

[0149] (1) Life of the boat support: the time period (number of rounds) from the first use of the boat support to the first cracks appearing after statistical processing;

[0150] (2) Appearance: Count the number of cracks on the surface of the boat support after 100 rounds of use;

[0151] (3) Topcon battery yield and conversion efficiency: Under the same production conditions, Topcon batteries of the same structure were produced using LPCVD boat supports treated by the methods of Examples 1 to 8 and LPCVD boat supports treated by the methods of Comparative Examples 1 to 4, and the yield and conversion efficiency of the Topcon batteries were tested.

[0152] The specific test results are shown in Table 1:

[0153] Table 1

[0154]

[0155]

[0156] As shown in Table 1, the present invention adopts the method to reduce the total gas consumption of saturation treatment and the number of saturation treatments, and significantly reduce the saturation treatment temperature; and this method can further reduce the amount of acid used in the early pickling process to reduce corrosion to the quartz boat support and extend the service life of the quartz boat support; the present invention adopts a specific pickling-water washing-purge pretreatment step to better remove contamination from the LPCVD boat support, reduce contamination to the quartz boat, improve the cleanliness of the furnace tube, and improve the battery yield and conversion efficiency.

[0157] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for processing LPCVD boat support of Topcon battery, characterized in that: The method comprises the following steps: H2 is introduced into the LPCVD boat support for a first saturation treatment, and then a mixed gas of H2 and N2O is introduced for a second saturation treatment to obtain a saturated LPCVD boat support; The total flow rate of the mixed gas in the second saturation treatment is 8 to 40 slm; wherein the flow rate ratio of H2 to N2O is 1:(4 to 9); the flow rate of H2 is 1.6 to 4 slm; and the flow rate of N2O is 6.4 to 36 slm.

2. The method for Topcon battery processing LPCVD boat support according to claim 1, characterized in that: The temperature of the first saturation treatment is 600-780°C.

3. The method for Topcon battery processing LPCVD boat support according to claim 1, characterized in that: The time of the first saturation treatment is 30 to 60 minutes.

4. The method for Topcon battery processing LPCVD boat support according to claim 1, characterized in that: The pressure of the first saturation treatment is 120-200 torr.

5. The method for Topcon battery processing LPCVD boat support according to claim 1, characterized in that: The gas flow rate of H2 in the first saturation treatment is 22-32 slm.

6. The method for Topcon battery processing LPCVD boat support according to claim 1, characterized in that: The temperature of the second saturation treatment is 500-600°C.

7. The method for Topcon battery processing LPCVD boat support according to claim 1, characterized in that: The time of the second saturation treatment is 60 to 90 minutes.

8. The method for Topcon battery processing LPCVD boat support according to claim 1, characterized in that: The pressure of the second saturation treatment is 320-420 torr.

9. The method for Topcon battery processing LPCVD boat support according to claim 1, characterized in that: Before introducing H2 for the first saturation treatment, the following pretreatment steps are also included: The LPCVD boat support is pickled using a mixed acid solution; Perform water washing on the LPCVD boat support after pickling; The LPCVD boat support is purged after water washing.

10. The method for Topcon battery processing LPCVD boat support according to claim 9, characterized in that: The mixed acid solution comprises the following components by mass percentage: 0.1-1% hydrogen chloride, 0.05-1% hydrogen fluoride, 0-0.5% oxidant, 0-0.2% complexing agent, 0-0.2% surfactant, and the balance is water.

11. The method for Topcon battery processing LPCVD boat support according to claim 10, characterized in that: The oxidant is selected from any one of hydrogen peroxide, peracetic acid or ammonium persulfate, or a combination of at least two thereof.

12. The method for Topcon battery processing LPCVD boat support according to claim 10, characterized in that: The complexing agent is selected from any one of ethylenediaminetetraacetic acid, hydroxyethyliminodiacetic acid, hydroxyethylethylenediaminetriacetic acid, diethyltriaminepentaacetic acid or triethyltetraaminehexaacetic acid, or a combination of at least two thereof.

13. The method for Topcon battery processing LPCVD boat support according to claim 10, characterized in that: The surfactant is selected from any one of palmitic acid, coconut oleic acid, polyethylene glycol, alkylphenol polyoxyethylene ether or fatty alcohol polyoxyethylene ether, or a combination of at least two thereof.

14. The method for Topcon battery processing LPCVD boat support according to claim 9, characterized in that: The specific steps of the pickling treatment are: firstly placing the LPCVD boat in the mixed acid solution for static soaking, and then performing ultrasonic rinsing.

15. The method for Topcon battery processing LPCVD boat support according to claim 14, characterized in that: The temperature of the static soaking is 10-30° C., and the time of the static soaking is 20-40 minutes.

16. The method for Topcon battery processing LPCVD boat support according to claim 14, characterized in that: The temperature of the ultrasonic rinsing is 30-40° C., the frequency of the ultrasonic rinsing is 30-40 kHz, and the time of the ultrasonic rinsing is 30-60 min.

17. The method for Topcon battery processing LPCVD boat support according to claim 9, characterized in that: The specific steps of the water washing treatment are: firstly place the LPCVD boat after the acid washing treatment in pure water for static soaking, and then spray rinse.

18. The method for Topcon battery processing LPCVD boat support according to claim 17, characterized in that: The temperature of the static soaking is 10-20° C., and the time of the static soaking is 10-30 minutes.

19. The method for Topcon battery processing LPCVD boat support according to claim 17, characterized in that: The temperature of the spray rinsing is 10-20°C, and the flow rate of the spray rinsing is 5-15m 3 / h, and the spray rinsing time is 30 to 90 minutes.

20. The method for Topcon battery processing LPCVD boat support according to claim 9, characterized in that: The gas used for the purging is nitrogen, the flow rate of the gas is 1 to 6 m / s, and the purging time is 5 to 15 min.

21. A quartz boat support for Topcon batteries, characterized in that: The quartz boat support for Topcon cells is obtained by processing the method for processing LPCVD boat supports for Topcon cells as described in any one of claims 1 to 10.

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