A graphite boat saturated film layer structure and preparation method thereof

Abstract

The present invention relates to the field of graphite boat production technology, specifically a graphite boat saturated film layer structure and a preparation method thereof; comprising a graphite boat body and a saturated film layer disposed on the surface of the graphite boat body; the saturated film layer is composed of the following raw materials by weight: 20 to 30 parts of adhesive, 3 to 6 parts of compounded nanopowder, 3 to 5 parts of functional filler, 2 to 4 parts of functional additive, and 4 to 7 parts of sintering aid; the present invention comprises placing the adhesive, compounded nanopowder, functional filler, functional additive, and sintering aid into a mixing device for mixing and stirring to obtain a film material, and then coating the obtained film material on the surface of the cleaned graphite boat body, sintering the film material, cooling the film material, and then inspecting the film material. The graphite boat saturated film layer structure prepared by the present invention not only has excellent corrosion resistance, but also has the effect of reducing product defective rate during use, effectively ensuring its quality and quality.

Description

Technical Field

[0001] The invention relates to the technical field of graphite boat production, in particular to a graphite boat saturated film layer structure and a preparation method thereof. Background Art

[0002] The graphite boat is a graphite mold. The graphite mold itself is a carrier that can be used to place the raw materials and parts that need to be positioned or shaped together in the graphite mold and sintered at high temperature. The graphite mold is made of artificial graphite through mechanical processing and has corresponding electrode sheets. The electrode sheets serve as the positive and negative poles of the power supply, thereby generating an electric field, ionizing the gas into plasma, and forming a new film layer.

[0003] The production and processing of solar silicon wafers involves a process called PECVD coating, which aims to improve the wafer's solar energy conversion efficiency. The PECVD coating process requires the use of a graphite boat. The silicon wafer to be coated is placed in the boat, where a chemical reaction occurs under certain conditions, depositing a film on the wafer's surface.

[0004] In the patent document with application number "CN202311862265.8" and titled "A graphite evaporation boat and its preparation method", it is recorded that "a coating structure is formed on the evaporation side of the evaporation boat, and the coating structure includes the following components in mass fraction: matrix filler 60%-80%; silicon 10-15%; nickel-aluminum composite powder, 1-5%; thermal conductive filler, 10-15%; adhesive 0.5-2%; and the coating structure is formed by hot pressing and sintering at increasing temperatures in succession. The present invention is based on a multi-component coating, and the components are easily formed into melt diffusion of different components through multiple hot pressing and sintering treatments at different temperatures. The internal crystalline components undergo multi-phase melting and reaction during the sintering process to gradually form a densified composite ceramic coating, which can improve the corrosion resistance of the graphite evaporation boat." Although this patent can achieve the effect of corrosion resistance, it is relatively insufficient in reducing the product defective rate during use, and still needs further improvement.

[0005] For example, the patent document with application number "CN202121290943.4" and name "Graphite boat saturated film layer structure and graphite boat for PERC solar cells" records that "it includes a first film layer, a second film layer and a third film layer deposited in sequence on the surface of the graphite boat body, the first film layer is a silicon carbide film or a silicon nitride film, the second film layer is an aluminum oxide film, and the third film layer is a silicon carbide film or a silicon nitride film. The graphite boat saturated film layer structure provided by the utility model can make the electric field distribution on the surface of the graphite boat more uniform, and make the saturated film layer structure of the graphite boat more stable, thereby making the silicon wafer coating uniformity better and preventing the problem of partial dark films and black edges on the coated silicon wafers." Although this patent can be used in the production of solar cells, its corrosion resistance and other properties are relatively insufficient and still need further improvement.

[0006] Based on this, the present invention provides a graphite boat saturated film layer structure and a preparation method thereof to solve the above-mentioned technical problems! Summary of the Invention

[0007] The purpose of the present invention is to provide a graphite boat saturated film layer structure and a preparation method thereof. The prepared graphite boat saturated film layer structure not only has excellent corrosion resistance, but also has the effect of reducing product defective rate during use, effectively ensuring its quality.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A first aspect of the present invention provides a graphite boat saturated film layer structure, comprising a graphite boat body and a saturated film layer disposed on the surface of the graphite boat body;

[0010] The saturated film layer is composed of the following raw materials in parts by weight: 20 to 30 parts of adhesive, 3 to 6 parts of compounded nanopowder, 3 to 5 parts of functional filler, 2 to 4 parts of functional additive and 4 to 7 parts of sintering aid.

[0011] Furthermore, the adhesive is selected from any one of epoxy resin adhesive and acrylic adhesive.

[0012] Furthermore, the compound nano powder is formed by mixing silicon, molybdenum and chromium in a mass ratio of 1:0.12-0.22:0.08-0.13.

[0013] Furthermore, the functional filler is formed by mixing and compounding the modified filler and alumina in a mass ratio of 1:0.08 to 0.28.

[0014] Furthermore, the preparation process of the modified filler is as follows:

[0015] An appropriate amount of carbon nitride powder is placed in an appropriate amount of modifying liquid at a solid-liquid ratio of 0.01 to 0.12 g / mL, stirred at 30 to 50 r / min for 10 to 14 minutes, then ultrasonically treated for 20 to 30 minutes, and then treated at a water bath temperature of 25 to 30 minutes and 120 to 140 r / min for 100 to 120 minutes. After filtration, the filter cake is washed 2 to 4 times with anhydrous ethanol and deionized water respectively;

[0016] After washing, the mixture is placed in a vacuum drying device at 60-70° C. and dried for 12-14 hours to obtain a modified filler.

[0017] Furthermore, the modified liquid is prepared by mixing the composite material and distilled water in a mass ratio of 0.12 to 0.22:1.

[0018] Furthermore, the composite material is formed by mixing aluminum phosphate and sodium phosphate in a mass ratio of 1:0.2 to 0.4.

[0019] Furthermore, the preparation process of the functional additive is as follows:

[0020] Aluminum nitride, oxalic acid, and nickel acetate tetrahydrate are placed in a stirring device and thoroughly mixed in a mass ratio of 1:0.26-0.36:0.12-0.24, and then placed in a grinding device and ground for 20-30 minutes to obtain a ground product;

[0021] The obtained ground product is placed under a nitrogen atmosphere and subjected to a two-stage high temperature treatment to obtain a functional additive;

[0022] Among them, the two-stage high temperature process is as follows:

[0023] The first stage: heating to 420℃ at a heating rate of 4-5℃ / min and keeping warm for 20-30min;

[0024] The second stage: heating to 500°C at a heating rate of 8°C / min and keeping warm for 40 to 50 minutes.

[0025] Furthermore, the sintering aid is formed by mixing nano-magnesium oxide and nano-zirconium dioxide in a mass ratio of 1:0.06 to 0.12.

[0026] The second aspect of the present invention further provides a method for preparing the above-mentioned graphite boat saturated film structure, which is characterized by comprising the following steps:

[0027] Step 1: Accurately weigh the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent, and put the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent into a mixing device for mixing and stirring to obtain a film material;

[0028] Step 2: coating the obtained film material on the surface of the cleaned graphite boat body, then heating to 105-120°C and keeping it warm for 5-8 minutes;

[0029] Step 3: In a vacuum environment of 6-12 Pa, heat the mixture to 720-740°C at a heating rate of 120-140°C / min, and keep the temperature for 6-10 minutes;

[0030] Step 4: Heat the temperature to 1720-1740°C at a heating rate of 80-100°C / min using nitrogen, maintain the temperature and pressure for 120-140 minutes under a hot pressing pressure of 28-30 MPa, cool, and then undergo an inspection process.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The saturated membrane layer structure of a graphite boat provided by the present invention comprises a graphite boat body and a saturated membrane layer arranged on the surface of the graphite boat body. The saturated membrane layer uses an adhesive, a compounded nanopowder, a functional filler, a functional additive and a sintering aid as raw materials, wherein the compounded nanopowder is compounded by mixing silicon, molybdenum and chromium, the functional filler is compounded by mixing a modified filler and alumina, the functional additive is obtained by mixing and grinding aluminum nitride, oxalic acid and nickel acetate tetrahydrate, and then subjecting them to a two-stage high-temperature treatment under a nitrogen atmosphere, and the sintering aid is obtained by mixing nano-magnesium oxide and nano-zirconium dioxide. The saturated membrane layer structure of the graphite boat provided by the present invention is obtained by adding the adhesive, the compounded nanopowder, the functional filler, the functional additive and the sintering aid into a mixing device for mixing and stirring to obtain a membrane material, and then coating the obtained membrane material on the surface of the cleaned graphite boat body, followed by sintering, cooling, and then undergoing an inspection process. The graphite boat saturated film structure prepared by the present invention not only has excellent corrosion resistance but also reduces product defect rates during use, effectively ensuring its quality. The graphite boat saturated film structure and preparation method provided by the present invention have a broader market prospect and are more suitable for promotion. DETAILED DESCRIPTION

[0033] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0034] Example 1

[0035] This embodiment provides a graphite boat saturated film layer structure, comprising a graphite boat body and a saturated film layer disposed on the surface of the graphite boat body;

[0036] The saturated film layer is composed of the following raw materials in parts by weight: 20 parts of adhesive, 3 parts of compound nanopowder, 3 parts of functional filler, 2 parts of functional additive and 4 parts of sintering aid.

[0037] Among them, the adhesive is epoxy resin adhesive.

[0038] In this embodiment, it should be noted that the epoxy resin adhesive was purchased from Shandong Huachen New Materials Co., Ltd.

[0039] The compound nano powder is prepared by mixing silicon, molybdenum and chromium in a mass ratio of 1:0.12:0.08.

[0040] Furthermore, the functional filler is prepared by mixing the modified filler and alumina in a mass ratio of 1:0.08.

[0041] The preparation process of the modified filler is as follows:

[0042] An appropriate amount of carbon nitride powder was placed in an appropriate amount of modifying liquid at a solid-liquid ratio of 0.01 g / mL, stirred at 30 r / min for 10 min, and then ultrasonically treated for 20 min. Then, the mixture was treated at a water bath temperature of 25 min and 120 r / min for 100 min. After filtration, the filter cake was washed twice with anhydrous ethanol and deionized water respectively.

[0043] After washing, the mixture was placed in a vacuum drying device at 60° C. and dried for 12 h to obtain a modified filler.

[0044] In addition, the modified liquid is prepared by mixing the composite material and distilled water in a mass ratio of 0.12:1.

[0045] The composite material is prepared by mixing aluminum phosphate and sodium phosphate in a mass ratio of 1:0.2.

[0046] The preparation process of functional additives is as follows:

[0047] Aluminum nitride, oxalic acid, and nickel acetate tetrahydrate were placed in a stirring device and thoroughly mixed in a mass ratio of 1:0.26:0.12, and then placed in a grinding device and ground for 20 minutes to obtain a ground product;

[0048] The obtained ground product is placed under a nitrogen atmosphere and subjected to a two-stage high temperature treatment to obtain a functional additive;

[0049] Among them, the two-stage high temperature process is as follows:

[0050] The first stage: heating to 420℃ at a heating rate of 4℃ / min and keeping at this temperature for 20min;

[0051] The second stage: heating to 500°C at a heating rate of 8°C / min and keeping warm for 40 minutes.

[0052] Furthermore, the sintering aid is formed by mixing nano-magnesium oxide and nano-zirconium dioxide in a mass ratio of 1:0.06.

[0053] In addition, this embodiment also provides a method for preparing the above-mentioned graphite boat saturated film layer structure, which is characterized by comprising the following steps:

[0054] Step 1: Accurately weigh the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent, and put the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent into a mixing device for mixing and stirring to obtain a film material;

[0055] Step 2: coating the obtained film material on the surface of the cleaned graphite boat body, then heating to 105°C and keeping it warm for 5 minutes;

[0056] The coating thickness is 0.8 mm.

[0057] Step 3: In a vacuum environment of 6 Pa, heat the sample to 720°C at a heating rate of 120°C / min and keep the temperature for 6 minutes;

[0058] Step 4: Heat the temperature to 1720°C at a heating rate of 80°C / min using nitrogen, maintain the temperature and pressure for 120 minutes under a hot pressing pressure of 28 MPa, cool, and then undergo the inspection process.

[0059] Example 2

[0060] The preparation method of the graphite boat saturated film structure provided in this embodiment is basically the same as that in Example 1, except that the specific raw material composition and the specific preparation method of the graphite boat saturated film structure in this embodiment are different. The specific raw material composition and the specific preparation method of the graphite boat saturated film structure in this embodiment are as follows:

[0061] This embodiment provides a graphite boat saturated film layer structure, comprising a graphite boat body and a saturated film layer disposed on the surface of the graphite boat body;

[0062] The saturated film layer is composed of the following raw materials in parts by weight: 25 parts of adhesive, 4 parts of compound nanopowder, 4 parts of functional filler, 3 parts of functional additive and 5 parts of sintering aid.

[0063] Among them, the adhesive is acrylic adhesive.

[0064] In this embodiment, it should be noted that the acrylic adhesive was purchased from Shantou Yulong New Material Technology Co., Ltd.

[0065] The compound nano powder is prepared by mixing silicon, molybdenum and chromium in a mass ratio of 1:0.17:0.11.

[0066] Furthermore, the functional filler is prepared by mixing the modified filler and alumina in a mass ratio of 1:0.18.

[0067] The preparation process of the modified filler is as follows:

[0068] An appropriate amount of carbon nitride powder was placed in an appropriate amount of modifying liquid at a solid-liquid ratio of 0.07 g / mL, stirred at 340 r / min for 12 min, and then ultrasonically treated for 25 min. Then, the mixture was treated at a water bath temperature of 27 min and 130 r / min for 110 min. After filtration, the filter cake was washed three times with anhydrous ethanol and deionized water respectively.

[0069] After washing, the mixture was placed in a vacuum drying device at 65° C. and dried for 13 h to obtain a modified filler.

[0070] In addition, the modified liquid is prepared by mixing the composite material and distilled water in a mass ratio of 0.17:1.

[0071] The composite material is prepared by mixing aluminum phosphate and sodium phosphate in a mass ratio of 1:0.3.

[0072] The preparation process of functional additives is as follows:

[0073] Aluminum nitride, oxalic acid, and nickel acetate tetrahydrate were placed in a stirring device and thoroughly mixed in a mass ratio of 1:0.31:0.18, and then placed in a grinding device and ground for 25 minutes to obtain a ground product;

[0074] The obtained ground product is placed under a nitrogen atmosphere and subjected to a two-stage high temperature treatment to obtain a functional additive;

[0075] Among them, the two-stage high temperature process is as follows:

[0076] The first stage: heating to 420℃ at a heating rate of 5℃ / min and keeping at this temperature for 25min;

[0077] The second stage: heating to 500°C at a heating rate of 8°C / min and keeping warm for 45 minutes.

[0078] Furthermore, the sintering aid is formed by mixing nano-magnesium oxide and nano-zirconium dioxide in a mass ratio of 1:0.09.

[0079] In addition, this embodiment also provides a method for preparing the above-mentioned graphite boat saturated film layer structure, which is characterized by comprising the following steps:

[0080] Step 1: Accurately weigh the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent, and put the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent into a mixing device for mixing and stirring to obtain a film material;

[0081] Step 2: Apply the obtained film material on the surface of the cleaned graphite boat body, then heat it to 115°C and keep it warm for 6 minutes;

[0082] The coating thickness is 0.8 mm.

[0083] Step 3: In a vacuum environment of 8 Pa, heat the sample to 730°C at a heating rate of 130°C / min and keep the temperature for 8 minutes;

[0084] Step 4: Heat the product to 1730°C at a heating rate of 90°C / min using nitrogen, maintain the temperature and pressure for 130 minutes under a hot pressing pressure of 29 MPa, cool the product, and then undergo the inspection process.

[0085] Example 3

[0086] The preparation method of the graphite boat saturated film structure provided in this embodiment is basically the same as that in Example 1, except that the specific raw material composition and the specific preparation method of the graphite boat saturated film structure in this embodiment are different. The specific raw material composition and the specific preparation method of the graphite boat saturated film structure in this embodiment are as follows:

[0087] This embodiment provides a graphite boat saturated film layer structure, comprising a graphite boat body and a saturated film layer disposed on the surface of the graphite boat body;

[0088] The saturated film layer is composed of the following raw materials in parts by weight: 30 parts of adhesive, 6 parts of compound nanopowder, 5 parts of functional filler, 4 parts of functional additive and 7 parts of sintering aid.

[0089] Among them, the adhesive is epoxy resin adhesive.

[0090] In this embodiment, it should be noted that the epoxy resin adhesive was purchased from Shandong Huachen New Materials Co., Ltd.

[0091] The compound nano powder is prepared by mixing silicon, molybdenum and chromium in a mass ratio of 1:0.22:0.13.

[0092] Furthermore, the functional filler is prepared by mixing the modified filler and alumina in a mass ratio of 1:0.28.

[0093] The preparation process of the modified filler is as follows:

[0094] An appropriate amount of carbon nitride powder was placed in an appropriate amount of modifying liquid at a solid-liquid ratio of 0.12 g / mL, stirred at 50 r / min for 14 min, and then ultrasonically treated for 30 min. Then, the mixture was treated at a water bath temperature of 30 min and 140 r / min for 120 min. After filtration, the filter cake was washed four times with anhydrous ethanol and deionized water respectively.

[0095] After washing, the mixture was placed in a vacuum drying device at 70° C. and dried for 14 h to obtain a modified filler.

[0096] In addition, the modified liquid is prepared by mixing the composite material and distilled water in a mass ratio of 0.22:1.

[0097] The composite material is prepared by mixing aluminum phosphate and sodium phosphate in a mass ratio of 1:0.4.

[0098] The preparation process of functional additives is as follows:

[0099] Aluminum nitride, oxalic acid, and nickel acetate tetrahydrate were placed in a stirring device and thoroughly mixed in a mass ratio of 1:0.36:0.24, and then placed in a grinding device and ground for 30 minutes to obtain a ground product;

[0100] The obtained ground product is placed under a nitrogen atmosphere and subjected to a two-stage high temperature treatment to obtain a functional additive;

[0101] Among them, the two-stage high temperature process is as follows:

[0102] The first stage: heating to 420℃ at a heating rate of 5℃ / min and keeping at this temperature for 30min;

[0103] The second stage: heating to 500°C at a heating rate of 8°C / min and keeping warm for 50 minutes.

[0104] Furthermore, the sintering aid is formed by mixing nano-magnesium oxide and nano-zirconium dioxide in a mass ratio of 1:0.12.

[0105] In addition, this embodiment also provides a method for preparing the above-mentioned graphite boat saturated film layer structure, which is characterized by comprising the following steps:

[0106] Step 1: Accurately weigh the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent, and put the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent into a mixing device for mixing and stirring to obtain a film material;

[0107] Step 2: coating the obtained film material on the surface of the cleaned graphite boat body, then heating to 120°C and keeping the temperature for 8 minutes;

[0108] The coating thickness is 0.8 mm.

[0109] Step 3: In a vacuum environment of 12 Pa, heat the sample to 740°C at a heating rate of 140°C / min and keep the temperature for 10 minutes;

[0110] Step 4: Heat the sample to 1740°C at a heating rate of 100°C / min using nitrogen, maintain the temperature and pressure for 140 minutes under a hot pressing pressure of 30 MPa, cool the sample, and then undergo the inspection process.

[0111] Comparative Example 1: The difference from Example 1 is that an equal amount of silicon is used instead of the compound nanopowder in this example.

[0112] Comparative Example 2: The difference from Example 1 is that in this example, an equal amount of aluminum oxide is used to replace the functional filler.

[0113] Comparative Example 3: The difference from Example 1 is that in this example, an equal amount of aluminum nitride is used to replace the functional auxiliary agent.

[0114] Comparative Example 4: The difference from Example 1 is that this example does not contain a sintering aid.

[0115] Performance test: The graphite boat saturated film layer samples provided in Examples 1 to 3 and Comparative Examples 1 to 4 were marked as Examples 1 to 3 and Comparative Examples 1 to 4, respectively; and the relevant properties of the graphite boat saturated film layers provided in Examples 1 to 3 and Comparative Examples 1 to 4 were tested as follows:

[0116] 1. Color Defect Rate Test: The test method is to place the graphite boats obtained from each group in the same furnace tube to produce PERC solar cells. The number and total number of color defects in each graphite boat are counted. Color Defect Rate = Number / Total × 100%.

[0117] 2. Anti-destruction test: The test method is to process a graphite boat with a size of 130*35*10. The boat to be tested is clamped at different electrode positions of the same evaporation equipment, and the same evaporation conditions are controlled. That is, the voltage and wire feeding speed are kept the same. The voltage is gradually increased in advance according to the gradient boost method. During stable evaporation, the power is controlled at around 3kW, the vacuum degree is controlled at above 10-2mba, and the wire feeding speed is controlled at a stable 400mm / min. Continuous evaporation is performed with an aluminum wire diameter of 1.8mm, and the failure time is recorded. The failure of the evaporation boat is judged as follows: after increasing the evaporation power, the boat cannot be lit, the aluminum wire cannot melt or evaporate, resulting in aluminum accumulation, or severe boiling occurs on the boat surface. The wire feeding is stopped and the failure time is recorded.

[0118] The obtained test data are recorded in Table 1 and Table 2 below:

[0119] Table 1 Test results of color defect rate of each group

[0120] Group EI dark film defect rate (%) Example 1 group 0.02 Example 2 group 0.03 Example 3 group 0.05 Comparison group 1 13.82 Comparison of 2 groups 14.55 Comparison of 3 groups 15.18 Comparison of 4 groups 13.78

[0121] Table 2 Anti-destruction test results of each group

[0122] Group Failure time (h) Example 1 group 9.2 Example 2 group 9.0 Example 3 group 9.2 Comparison group 1 5.2 Comparison of 2 groups 5.8 Comparison of 3 groups 6.1 Comparison of 4 groups 5.0

[0123] Comparing and analyzing the relevant data in Tables 1 and 2 demonstrates that the graphite boat saturated film structure prepared in the present invention not only exhibits excellent corrosion resistance but also reduces product defect rates during use, effectively ensuring its quality. This demonstrates that the graphite boat saturated film structure and preparation method provided by the present invention have broad market prospects and are more suitable for promotion.

[0124] The saturated membrane layer structure of a graphite boat provided by the present invention comprises a graphite boat body and a saturated membrane layer arranged on the surface of the graphite boat body. The saturated membrane layer uses an adhesive, a compounded nanopowder, a functional filler, a functional additive and a sintering aid as raw materials, wherein the compounded nanopowder is compounded by mixing silicon, molybdenum and chromium, the functional filler is compounded by mixing a modified filler and alumina, the functional additive is obtained by mixing and grinding aluminum nitride, oxalic acid and nickel acetate tetrahydrate, and then subjecting them to a two-stage high-temperature treatment under a nitrogen atmosphere, and the sintering aid is obtained by mixing nano-magnesium oxide and nano-zirconium dioxide. The saturated membrane layer structure of the graphite boat provided by the present invention is obtained by adding the adhesive, the compounded nanopowder, the functional filler, the functional additive and the sintering aid into a mixing device for mixing and stirring to obtain a membrane material, and then coating the obtained membrane material on the surface of the cleaned graphite boat body, followed by sintering, cooling, and then undergoing an inspection process. The graphite boat saturated film layer structure prepared by the present invention not only has excellent corrosion resistance, but also has the effect of reducing product defective rate when used, effectively ensuring its quality.

[0125] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0126] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A graphite boat saturated film structure, characterized in that: It comprises a graphite boat body and a saturated film layer arranged on the surface of the graphite boat body; The saturated film layer is composed of the following raw materials in parts by weight: 20 to 30 parts of adhesive, 3 to 6 parts of compounded nanopowder, 3 to 5 parts of functional filler, 2 to 4 parts of functional additive and 4 to 7 parts of sintering aid; The composite nano powder is prepared by mixing silicon, molybdenum and chromium in a mass ratio of 1:0.12-0.22:0.08-0.13; The functional filler is prepared by mixing the modified filler and alumina in a mass ratio of 1:0.08-0.28; The preparation process of the modified filler is as follows: An appropriate amount of carbon nitride powder is placed in an appropriate amount of modifying liquid at a solid-liquid ratio of 0.01 to 0.12 g / mL, stirred at 30 to 50 r / min for 10 to 14 minutes, then ultrasonically treated for 20 to 30 minutes, and then treated at a water bath temperature of 25 to 30 minutes and 120 to 140 r / min for 100 to 120 minutes. After filtration, the filter cake is washed 2 to 4 times with anhydrous ethanol and deionized water respectively; After washing, the mixture is placed in a vacuum drying device at 60-70°C and dried for 12-14 hours to obtain a modified filler; The modified liquid is prepared by mixing the composite material and distilled water in a mass ratio of 0.12 to 0.22:1; The composite material is prepared by mixing aluminum phosphate and sodium phosphate in a mass ratio of 1:0.2 to 0.4; The preparation process of the functional additive is as follows: Aluminum nitride, oxalic acid, and nickel acetate tetrahydrate are placed in a stirring device and thoroughly mixed in a mass ratio of 1:0.26-0.36:0.12-0.24, and then placed in a grinding device and ground for 20-30 minutes to obtain a ground product; The obtained ground product is placed under a nitrogen atmosphere and subjected to a two-stage high temperature treatment to obtain a functional additive; Among them, the two-stage high temperature process is as follows: The first stage: heating to 420℃ at a heating rate of 4-5℃ / min and keeping warm for 20-30min; The second stage: heating to 500℃ at a heating rate of 8℃ / min and keeping warm for 40-50min; The sintering aid is prepared by mixing nano magnesium oxide and nano zirconium dioxide in a mass ratio of 1:0.06-0.

12.

2. The graphite boat saturated film structure according to claim 1, characterized in that: The adhesive is selected from any one of epoxy resin adhesive and acrylic adhesive.

3. The method for preparing a graphite boat saturated film structure according to any one of claims 1 to 2, characterized in that: The following steps are involved: Step 1: Accurately weigh the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent, and put the adhesive, compounded nanopowder, functional filler, functional additive and sintering agent into a mixing device for mixing and stirring to obtain a film material; Step 2: coating the obtained film material on the surface of the cleaned graphite boat body, then heating to 105-120°C and keeping it warm for 5-8 minutes; Step 3: In a vacuum environment of 6-12 Pa, heat the mixture to 720-740°C at a heating rate of 120-140°C / min, and keep the temperature for 6-10 minutes; Step 4: Heat the temperature to 1720-1740°C at a heating rate of 80-100°C / min using nitrogen, maintain the temperature and pressure for 120-140 minutes under a hot pressing pressure of 28-30 MPa, cool, and then undergo an inspection process.