Chemical vapor deposition silicon carbide apparatus

Abstract

The utility model discloses chemical vapor deposition silicon carbide equipment, including deposition chamber, first gas cylinder, second gas cylinder, third gas cylinder, fourth gas cylinder, mechanical pump, support structure and fan, be equipped with deposition cavity in the deposition chamber, first gas cylinder passes through first pipeline with deposition cavity, and first pipeline is equipped with first manual valve, first flow meter and first pneumatic valve in proper order, and second gas cylinder passes through second pipeline with first pipeline, and second pipeline is equipped with second manual valve, second flow meter and second pneumatic valve in proper order, and third gas cylinder passes through third pipeline with deposition cavity, and third pipeline is equipped with third manual valve, third flow meter and third pneumatic valve in proper order, and fourth gas cylinder passes through fourth pipeline with deposition cavity, the utility model discloses simple structure, reasonable in design can high -efficiently complete chemical vapor deposition silicon carbide, and deposition rate has advantages such as high.

Description

Technical Field

[0001] This utility model belongs to the field of chemical vapor deposition technology, specifically relating to a chemical vapor deposition silicon carbide equipment. Background Technology

[0002] Currently, the heating elements used in the electronic atomization field are mainly composed of two coupled parts: porous ceramic and metal. The metal part generally has two structures: the first involves winding various heating wires into a spring shape or etching or stamping a metal substrate into a mesh shape and welding leads to the ends to form a whole; the second involves vertically welding leads to both ends of an etched or stamped mesh-shaped metal substrate. Both structures have leads exposed to the air, with lead diameters typically between 0.20mm and 0.40mm. During the sintering process of the heating element, these leads are prone to fracture, especially at high temperatures, where brittle fracture is more likely. Currently, the leads of heating elements often use pure nickel. Due to the low alloy content of pure nickel wire, it is more susceptible to hydrogen embrittlement at high temperatures. Furthermore, since porous ceramics are generally injection molded, the ceramic part contains a large amount of hydrogenated paraffin during molding, which causes a rapid increase in hydrogen content in the sintering atmosphere, thus increasing the likelihood of hydrogen embrittlement. To mitigate the effects of hydrogen embrittlement, either a barrier coating is used to prevent it from penetrating the pure nickel wire, or the metal of the lead portion undergoes chemical and microstructural modification. However, these methods significantly increase costs, and current barrier coatings are mostly electroplated or electroless metal plating. During pickling, cathodic electrolytic degreasing, and metal deposition in aqueous electrolytes, a large number of hydrogen atoms are absorbed by the surface, exacerbating hydrogen embrittlement. Therefore, it is essential to develop a chemical vapor deposition (CVD) silicon carbide equipment to perform CVD silicon carbide deposition on pure nickel wire as a hydrogen barrier coating to protect the lead portion. Utility Model Content

[0003] In order to overcome the shortcomings of the prior art, this utility model provides a chemical vapor deposition (CVD) silicon carbide equipment that can efficiently deposit silicon carbide.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] Chemical vapor deposition equipment for silicon carbide includes:

[0006] A sedimentation chamber, wherein a sedimentation cavity is provided within the sedimentation chamber;

[0007] The first gas cylinder is connected to the sedimentation chamber through the first pipeline, and the first pipeline is sequentially equipped with a first manual valve, a first flow meter and a first pneumatic valve;

[0008] The second gas cylinder is connected to the first pipeline through the second pipeline. The second pipeline is equipped with a second manual valve, a second flow meter and a second pneumatic valve in sequence.

[0009] The third gas cylinder is connected to the sedimentation chamber through the third pipeline. The third pipeline is equipped with a third manual valve, a third flow meter and a third pneumatic valve in sequence.

[0010] The fourth gas cylinder is connected to the sedimentation chamber through the fourth pipeline. The fourth pipeline is equipped with a fourth manual valve, a fourth flow meter, and a fourth pneumatic valve in sequence.

[0011] A mechanical pump is connected to the sedimentation chamber via a fifth pipe, and a fifth pneumatic valve is installed on the fifth pipe;

[0012] A support structure is installed inside the deposition chamber and is used to mount the spool;

[0013] A fan is located at the bottom of the deposition chamber;

[0014] The first gas cylinder is an argon cylinder, the second gas cylinder is a silicon tetrachloride cylinder, the third gas cylinder is a methyltrichlorosilane cylinder, and the fourth gas cylinder is a nitrogen cylinder.

[0015] Preferably, the bottom of the deposition chamber is provided with a support frame, the deposition chamber is cylindrical, and the deposition chamber includes a first layer, a second layer, a third layer and a fourth layer from the inside to the outside. The first layer is made of mullite tube material, the second layer is made of electric heating tube material, the third layer is made of heat insulation material, and the fourth layer is made of quartz tube material or corundum tube material.

[0016] Preferably, the support structure includes a first support and a second support arranged at intervals. The first support and the second support have the same structure. The top of the first support is connected to the inner wall of the deposition chamber through a rotating device. The first support is provided with at least one set of spool mounting modules, which are rotatably mounted on the first support.

[0017] By adopting the above technical solution, this utility model has the following beneficial effects:

[0018] This utility model has a deposition chamber, a first gas cylinder, a second gas cylinder, a third gas cylinder, a fourth gas cylinder, and a mechanical pump. In actual use, the gas circulates in the deposition chamber, which improves the deposition rate and can efficiently complete the chemical vapor deposition of silicon carbide. The overall structure is simple and the design is reasonable.

[0019] In summary, this utility model has the advantages of simple structure, reasonable design, high efficiency in chemical vapor deposition of silicon carbide, and high deposition rate. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of this utility model;

[0021] Figure 2 This is a schematic diagram of the structure of the first support of this utility model. Detailed Implementation

[0022] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0023] The components of the present invention embodiments described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0024] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0025] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0027] Example 1

[0028] In this embodiment, a chemical vapor deposition silicon carbide device is proposed, which mainly performs chemical vapor deposition of silicon carbide as a hydrogen barrier coating on the lead portion of the heating element in the field of electronic atomization, thereby reducing hydrogen embrittlement.

[0029] like Figure 1 and Figure 2As shown, in one embodiment of this utility model, the chemical vapor deposition silicon carbide equipment of this utility model includes a deposition chamber 1, a first gas cylinder 2, a second gas cylinder 3, a third gas cylinder 4, a fourth gas cylinder 5, a mechanical pump 6, a support structure, and a fan 7. The deposition chamber 1 contains a deposition cavity 8, and a support frame 9 is provided at the bottom of the deposition chamber 1. The deposition chamber 1 is cylindrical and includes, from the inside out, a first layer, a second layer, a third layer, and a fourth layer. The first layer is made of mullite tube material, the second layer is made of heating tube material, the third layer is made of insulation material, and the fourth layer is made of quartz tube material or corundum tube material, thereby constructing the deposition chamber 1 and the deposition cavity 8 within the deposition chamber 1. Figure 1 The direction of the middle arrow indicates the direction of gas flow;

[0030] Continue to refer to Figure 1The first gas cylinder 2 of this invention is connected to the sedimentation chamber 8 via a first pipe 10. The first pipe 10 is sequentially equipped with a first manual valve 11, a first flow meter 12, and a first pneumatic valve 13. The second gas cylinder 3 is connected to the first pipe 10 via a second pipe 14. The second pipe 14 is sequentially equipped with a second manual valve 15, a second flow meter 16, and a second pneumatic valve 17. The third gas cylinder 4 is connected to the sedimentation chamber 8 via a third pipe 18. The third pipe 18 is sequentially equipped with a third manual valve 19, a third flow meter 20, and a third pneumatic valve 21. The fourth gas cylinder 5 is connected to the sedimentation chamber 8 via a fourth pipe 22. The deposition chamber 8 is connected to the fourth pipeline 22, which is sequentially equipped with a fourth manual valve 23, a fourth flow meter 24, and a fourth pneumatic valve 25. Specifically, the first gas cylinder 2 is an argon cylinder, the second gas cylinder 3 is a silicon tetrachloride cylinder, the third gas cylinder 4 is a methyltrichlorosilane cylinder, and the fourth gas cylinder 5 is a nitrogen cylinder. In use, the first gas cylinder 2, the second gas cylinder 3, the third gas cylinder 4, and the fourth gas cylinder 5 can cooperate to introduce various gases into the deposition chamber 8 to perform chemical vapor deposition of silicon carbide. The mechanical pump 6 of this invention is connected to the deposition chamber 8 through a fifth pipeline 26, which is equipped with a fifth pneumatic valve 27. The support structure is set inside the deposition chamber 8 and is used to install the spool. The fan 7 is located at the bottom of the deposition chamber 8. The fan 7 can circulate the gas in the deposition chamber 8 during deposition, thereby increasing the deposition rate of the lower surface of the pure nickel wire (this utility model mainly targets pure nickel wire, that is, the spool is equipped with pure nickel wire). The fan 7 at the bottom of the deposition chamber 8 and the gas cylinders can be turned on before heating. At this time, impurities in the deposition chamber 1 can be cleaned, waste gas can be removed, and a good deposition atmosphere can be ensured. Alternatively, it can be turned on after heating and before starting the gas inlet equipment. At this time, argon can be used as a carrier gas for preheating, reducing the induction period time during deposition, or Furthermore, when the temperature is raised and the air intake device is started, the rate at which the silicon carbide powder, which is initially deposited downwards under the influence of gravity, descends is reduced, ensuring the consistency of the coating during the deposition process. In this invention, the gas flow rate can be observed through the first flow meter 12, the second flow meter 16, the third flow meter 20, and the fourth flow meter 24, and the gas flow rate can be adjusted through the first manual valve 11, the second manual valve 15, the third manual valve 19, the fourth manual valve 23, the first pneumatic valve 13, the second pneumatic valve 17, the third pneumatic valve 21, the fourth pneumatic valve 25, and the fifth pneumatic valve 27.

[0031] Please refer to this again. Figure 1 and Figure 2The support structure includes a first support 28 and a second support 29 spaced apart. The first support 28 and the second support 29 have the same structure and are both located inside the deposition chamber 8. The top of the first support 28 is connected to the inner wall of the deposition chamber 1 via a rotating device 30. At least one set of spool mounting modules is provided on the first support 28. The spool mounting modules are rotatably mounted on the first support 28. The spool mounting modules include a locking part 281, a movable shaft 282, and a mating limiting part 283. The mating limiting part 283 is provided on the first support 28, and the movable shaft 282... The locking part 281 is movably mounted on the movable shaft 282 and the fitting limiting part 283 is installed on the fitting limiting part 283. Similarly, the top of the second bracket 29 is connected to the inner wall of the sedimentation chamber 1 through a rotating device 30. The second bracket 29 is provided with at least one set of bobbin mounting modules. The bobbin mounting modules are rotatably mounted on the second bracket 29. The bobbin mounting modules include a locking part 281, a movable shaft 282 and a fitting limiting part 283. The fitting limiting part 283 is provided on the first bracket 28, the movable shaft 282 is mounted on the fitting limiting part 283, and the locking part 281 is movably mounted on the movable shaft 282.

[0032] This invention is applicable to chemical vapor deposition of pure nickel wire. The specific operation steps are as follows:

[0033] S1. Perform surface pretreatment on the pure nickel wire by cleaning the oxide layer on the surface of the pure nickel wire with acetone. The pure nickel wire used is selected from N6 grade industrial high-purity nickel raw materials, and the purity of nickel in the raw materials is not less than 99.5%.

[0034] S2. Clean the deposition chamber 1. Place 5 spools of pure nickel wire from bottom to top on the first support 28 on one side of the deposition chamber 1. Place 5 empty spools on the second support 29. Then connect the spools on both sides one by one. After completion, close the door of the deposition chamber 1 and evacuate to measure the pressure rise rate.

[0035] S3. Evacuate for 15-20 minutes until the pressure is below 0 Pa. Turn off the vacuum pump and wait 40-50 minutes to obtain the final pressure value. If the pressure rise is ≤2 Pa, production can continue. If it is greater than 2 Pa, production must be stopped and the equipment must be checked for leaks.

[0036] S4. During production, vacuum the deposition chamber 1 to maintain a pressure of approximately 10 kPa, and then raise the temperature according to the temperature control procedure. The specific temperature curves are as follows: room temperature 30℃ vacuum for 1.5 h, 30℃-500℃ vacuum for 1.5 h, 500℃ vacuum for 1.5 h, 500℃-1000℃ vacuum for 1 h, 1000℃ vacuum for 1 h, 1000℃-1100℃ vacuum for 1 h, 1100℃ vacuum for 30 min, 1100℃-1200℃ vacuum for 30 min, 1200℃ vacuum for 30 min, 1200℃-1300℃ vacuum for 30 min.

[0037] S5. When the temperature reaches 1300℃, turn on the fan 7 at the bottom of the deposition chamber 8 and open the first gas cylinder 2 (introduce argon gas and turn on the mechanical pump 6). After 5 minutes, start the gas inlet device. After 30 minutes, turn on the rotating device 30 of the first support 28 and the second support 29. The rotation speed of the first support 28 and the second support 29 is 1-2 r / min. The gas flow rate is 2000 sccm of methyltrichlorosilane, 1000 sccm of silicon tetrachloride, and 1000 sccm of argon gas.

[0038] S6. After the deposition time of 9 hours has been reached, stop the ventilation, evacuate to below 0 Pa and stop heating, and allow automatic cooling.

[0039] S7. When the temperature drops below 500℃, argon gas is introduced to a pressure of about 130kPa.

[0040] S8. After cooling to room temperature, purge with nitrogen to replace the spool, open deposition chamber 1 as required, and remove the spool.

[0041] Currently used hydrogen permeation barrier materials are mostly aluminum oxide and TiC, which are formed by electroplating or chemical plating. However, this method causes a large number of hydrogen atoms in the solution to be absorbed by the surface of the pure nickel wire, accelerating the occurrence of hydrogen embrittlement. Chemical deposition forms a coating through the reaction between gases, avoiding the aggravation of hydrogen embrittlement. This invention uses vapor-phase deposition of silicon carbide on pure nickel leads to reduce the impact of hydrogen embrittlement on ceramic heating element leads, improve product quality, and reduce production costs. Moreover, commonly used coating materials are mostly metals, and metals with small voltage drops are more expensive, such as silver. Because silicon carbide has a wide bandgap of 3 electron volts, it can withstand high voltage and has a high bandgap, so it allows for a smaller heating element size and higher operating performance. It is widely used in high-power devices. Therefore, pure nickel wire with vapor-phase deposition of silicon carbide has broad prospects in the field of high-power electronic atomization.

[0042] This embodiment does not impose any limitation on the shape, material, structure, etc. of this utility model. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this utility model shall fall within the protection scope of this utility model.

Claims

1. A chemical vapor deposition (CVD) silicon carbide equipment, characterized in that, include: A sedimentation chamber, wherein a sedimentation cavity is provided within the sedimentation chamber; The first gas cylinder is connected to the sedimentation chamber through the first pipeline, and the first pipeline is sequentially equipped with a first manual valve, a first flow meter and a first pneumatic valve; The second gas cylinder is connected to the first pipeline through the second pipeline. The second pipeline is equipped with a second manual valve, a second flow meter and a second pneumatic valve in sequence. The third gas cylinder is connected to the sedimentation chamber through the third pipeline. The third pipeline is equipped with a third manual valve, a third flow meter and a third pneumatic valve in sequence. The fourth gas cylinder is connected to the sedimentation chamber through the fourth pipeline. The fourth pipeline is equipped with a fourth manual valve, a fourth flow meter, and a fourth pneumatic valve in sequence. A mechanical pump is connected to the sedimentation chamber via a fifth pipe, and a fifth pneumatic valve is installed on the fifth pipe; A support structure is installed inside the deposition chamber and is used to mount the spool; A fan is located at the bottom of the deposition chamber; The first gas cylinder is an argon cylinder, the second gas cylinder is a silicon tetrachloride cylinder, the third gas cylinder is a methyltrichlorosilane cylinder, and the fourth gas cylinder is a nitrogen cylinder.

2. The chemical vapor deposition silicon carbide apparatus according to claim 1, characterized in that: The bottom of the sedimentation chamber is equipped with a support frame. The sedimentation chamber is cylindrical and includes a first layer, a second layer, a third layer and a fourth layer from the inside to the outside. The first layer is made of mullite tube material, the second layer is made of electric heating tube material, the third layer is made of heat insulation material, and the fourth layer is made of quartz tube material or corundum tube material.

3. The chemical vapor deposition silicon carbide apparatus according to claim 1, characterized in that: The support structure includes a first support and a second support arranged at intervals. The first support and the second support have the same structure. The top of the first support is connected to the inner wall of the deposition chamber through a rotating device. The first support is provided with at least one set of spool mounting modules, which are rotatably mounted on the first support.

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