Methods for improving raw gas efficiency

Abstract

The present invention relates to a method for improving the efficiency of raw material gas quantity, and the carrier gas in contact with the source in the storage container is preheated first to stabilize the thermal balance in the storage container and the vapor pressure of the source; the carrier gas can be preheated first by an internal heating method or an external heating method, and the internal heating method is to set a carrier gas preheating pipe in the storage container, the inlet of the carrier gas preheating pipe is connected to the carrier gas inlet pipe, the outlet is connected to the chamber of the storage source, and the storage container is placed in the heat source; the external heating method is to set a carrier gas preheating pipe outside the storage container, the inlet of the carrier gas preheating pipe is connected to the carrier gas pipeline, the outlet is connected to the bottom tube, the bottom tube is inserted into the storage container, and the carrier gas preheating pipe is provided with a heating unit. By effectively preheating the carrier gas, the temperature reduction caused to the raw material when the normal temperature gas passes through the raw material is reduced, and the problem of unstable gas loading is avoided.

Description

Technical Field

[0001] The invention relates to a method for improving the efficiency of raw material gas quantity, belonging to the technical field of semiconductor source application. Background Art

[0002] Semiconductor source products are available in gaseous, liquid and solid states at room temperature. For gaseous sources, the raw material concentration can be controlled by controlling the opening degree of the valve under constant temperature and pressure. For liquid sources, the raw material concentration can be stabilized by controlling the intake volume of the carrier gas under constant temperature. Solid sources are mainly metal chlorides, trimethylindium, bismuth magnesium and carbon tetrabromide.

[0003] The source concentration in the carrier gas is related to many factors, such as the size of the solid particles, the particle stacking form, the carrier gas passage path, the temperature, and the particle compaction, which makes it difficult to control the raw material concentration of the solid source. Once the raw material concentration drops, the compound semiconductor layer of the prepared chip will have inconsistent microstructures, and ultimately produce a lot of defective products. In order to ensure the stability of the raw material concentration, most solid sources are replaced before they are completely used up, resulting in losses in manpower, material resources, and financial resources.

[0004] Most of the current storage containers have only one chamber in the bottle body, the contact time between the carrier gas and the source is short, the heat exchange is insufficient, and the room temperature carrier gas enters the high-temperature steel cylinder, which lowers the temperature inside the bottle and breaks the balance of the solid source vapor pressure in the bottle, resulting in unstable gas pressure in the bottle and low source utilization. On the other hand, the existing steel cylinders have different spatial structures, dead corners, inconvenience in cleaning, and it is not easy to ensure cleanliness. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for improving the efficiency of raw gas volume, aiming to improve the thermal balance in the storage container, ensure the stability of the vapor pressure of the source, and increase the material loading per unit volume.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] The method for improving the efficiency of raw material gas volume is characterized by preheating the carrier gas in contact with the source in the storage container to stabilize the thermal balance in the storage container and the vapor pressure of the source.

[0008] Furthermore, in the above-mentioned method for improving the efficiency of the raw material gas, the carrier gas is preheated by an internal heating method or an external heating method. The internal heating method is to set a carrier gas preheating tube in the storage container, the inlet of the carrier gas preheating tube is connected to the carrier gas inlet pipe, and the outlet is connected to the chamber of the storage source, and the storage container is placed in the heat source;

[0009] The external heating method is to set a carrier gas preheating tube outside the storage container, the inlet of the carrier gas preheating tube is connected with the carrier gas inlet pipe, the outlet is connected with the bottom insert tube, the bottom insert tube is inserted into the storage container, and the carrier gas preheating tube is provided with a heating unit.

[0010] Furthermore, in the above-mentioned method for improving the efficiency of raw material gas quantity, in which, in the internal heating method, a carrier gas preheating pipe is arranged at the bottom end of the storage container, and a plurality of movable carrier plates are arranged in the storage container, which divides the inner cavity of the storage container from bottom to top into a plurality of chambers, and each layer of the carrier plate is provided with a connecting pipe for connecting the upper chamber with the lower chamber, and each layer of the carrier plate is also provided with a central hole for plugging a central tube, the central tube passes through each layer of the carrier plate, and its top end is connected to the carrier gas inlet pipe, and the bottom end is connected to the carrier gas preheating pipe, the outlet of the carrier gas preheating pipe is located in the chamber where the carrier gas preheating pipe is located, and the air outlet pipe is connected to the uppermost chamber; the carrier gas enters the central pipe through the carrier gas inlet pipe, and then the carrier gas enters the chamber after being preheated by the carrier gas preheating pipe, and passes through the connecting pipe of each layer of the carrier plate from bottom to top in turn with the source steam, and is finally transported out from the air outlet pipe. The carrier gas is preheated through the carrier gas preheating pipe, thereby avoiding uneven air intake and unstable air pressure inside the container, and improving the utilization rate of the source.

[0011] Furthermore, in the above method for improving the efficiency of raw gas quantity, the carrier gas preheating tube is a spiral coil.

[0012] Furthermore, in the above-mentioned method for improving the efficiency of raw gas quantity, each layer of the carrier plate is provided with a central opening and two connecting pipes, which are located in a straight line in the radial direction, and the two connecting pipes are symmetrical with the central opening as the center. The line connecting the connecting pipe and the central opening on each layer of the carrier plate and the line connecting the connecting pipe and the central opening on the adjacent carrier plate are vertical in the axial projection.

[0013] Furthermore, in the above-mentioned method for improving the efficiency of raw gas quantity, the center tube and the carrier gas preheating tube are welded as one, the center tube passes through the center opening on each layer of the carrier plate, and the top end thereof is connected to the flange by a thread, and the support plate at the welding point of the center tube and the carrier gas preheating tube tightly contacts the carrier plate together.

[0014] Furthermore, in the above-mentioned method for improving the efficiency of raw gas volume, a filter is provided at the inlet of the gas outlet pipe.

[0015] Furthermore, in the above-mentioned method for improving the efficiency of raw gas quantity, the outlet of the carrier gas preheating tube is located at the bottom of the chamber where the carrier gas preheating tube is located.

[0016] Furthermore, in the above-mentioned method for improving the efficiency of raw material gas quantity, the source carrier plate has 2 to 8 layers, which are arranged at intervals from bottom to top.

[0017] Furthermore, in the above-mentioned method for improving the efficiency of raw gas quantity, in which, in the external heating method, a bottom tube is inserted into the bottom of the storage container, and an arc-shaped buffer groove is provided on the bottom plate of the storage container opposite to the bottom tube; the carrier gas is first heated to the same temperature as the storage container by a carrier gas preheating tube before entering the chamber of the storage container.

[0018] Compared with the prior art, the present invention has significant advantages and beneficial effects, which are specifically embodied in the following aspects:

[0019] ① The present invention effectively preheats the carrier gas to reduce the temperature drop of the raw material caused by the normal temperature gas passing through the raw material, thereby avoiding the problem of unstable gas loading; the carrier gas preheating method can be internal heating or external heating; the raw material is evenly dispersed in the multi-layer carrier plate to increase the contact time and area between the gas and the material, thereby increasing the material loading per unit volume;

[0020] ② Internal heating method, built-in carrier gas preheating tube, a multi-layer carrier source plate structure is set in the bottle, the carrier gas preheating tube prolongs the residence time of the gas in the bottle, the carrier gas enters the bottle from the air inlet during air intake, and is fully heated in the carrier gas preheating tube, improving the heat balance in the cylinder and ensuring the stability of the source vapor pressure; and the carrier gas preheating tube has a supporting effect on the carrier source plate;

[0021] ③ The bottle of internal heating method is equipped with multiple layers of source plates. After being blocked by the layers of source plates, the carrier gas presents an S-shaped flow in the bottle 4, which greatly increases the contact time with the source, effectively avoids the uneven and unstable air pressure inside the cylinder, and improves the effect of stabilizing the source vapor pressure;

[0022] ④ The multi-layer source plate in the bottle of internal heating method is movable and can be taken out for separate cleaning. There is no dead corner, which solves the problem of incomplete cleaning.

[0023] ⑤ External heating method: an external carrier gas preheating tube is installed. The carrier gas is first heated to the same temperature as the cylinder through the carrier gas preheating tube, and then enters the cylinder through the bottom tube. Its structure is simple, and the carrier gas preheating tube can adopt a separate heating setting according to actual use, and its length can also be controlled.

[0024] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or be understood by practicing the specific embodiments of the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 : Schematic diagram of the device structure of the internal heating method;

[0027] Figure 2 : Schematic diagram of the device structure of the external heating method. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various 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 represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

[0029] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, directional terms and order terms are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0030] The present invention develops a method for improving the efficiency of raw material gas, wherein the carrier gas in contact with the source in the storage container is preheated to stabilize the thermal balance in the storage container and the vapor pressure of the source. Specifically, the carrier gas is preheated by an internal heating method or an external heating method.

[0031] like Figure 1As shown, the internal heating method is to set a carrier gas preheating tube 10 in the storage container 3. The storage container 3 is a steel cylinder structure, and the material is 316L stainless steel. The pneumatic valve group 6 is used to control the passage and closure of the air inlet pipe and the air outlet pipe. The pneumatic valve is used to facilitate automatic control; the storage container 3 is used to fill the high-purity solid source, the flange 3 is combined with the screws to close the outer bottle body, and plays the role of connecting the air pipe and the outer bottle body, the handle 2 is used to carry the steel cylinder, and the carrier gas preheating tube 10 is a spiral coil made of a hollow stainless steel tube; the carrier gas preheating tube 10 is arranged at the bottom end of the storage container, and the storage container is provided with a multi-layer movable source plate 11, which divides the inner cavity of the storage container from bottom to top into a plurality of chambers, and each layer of the source plate is provided with a connection for connecting the upper chamber with the lower chamber A connecting pipe 9 is provided, and each layer of the source plate is also provided with a center hole for the central tube to be plugged in. The central tube 8 passes through each layer of the source plate, and its top end is connected with the carrier gas inlet pipe 1, and the bottom end is connected with the carrier gas preheating pipe 10. The outlet of the carrier gas preheating pipe 10 is located at the bottom of the chamber where the carrier gas preheating pipe is located. The outlet pipe 5 is connected with the uppermost chamber, and the inlet of the outlet pipe 5 is provided with a 100-micron filter screen 12; the storage container is placed in the heat source; the carrier gas enters the central pipe 8 through the carrier gas inlet pipe 1, and then the carrier gas enters the chamber after being preheated by the carrier gas preheating pipe 10, and passes through the connecting pipe of each layer of the source plate from bottom to top in turn with the source steam, and is finally transported out from the outlet pipe 5. The carrier gas is preheated through the carrier gas preheating pipe 10, so as to avoid uneven air intake and unstable air pressure inside the container and improve the utilization rate of the source.

[0032] During the design, the source plate has 2 to 8 layers, which are arranged at intervals from bottom to top; each layer of the source plate is provided with a central opening and two connecting pipes, which are located on a straight line in the radial direction, and the two connecting pipes are symmetrical with the central opening as the center. The connecting line between the connecting pipe and the central opening on each layer of the source plate and the connecting line between the connecting pipe and the central opening on the adjacent source plate are perpendicular to each other in the axial projection; the path of the carrier gas passing through the solid source is significantly lengthened, presenting an S-shaped flow, and the carrier gas is fully in contact with the source to increase the contact time between the gas and the material and increase the material loading per unit volume. In addition, the source plate is a movable structure and can be taken out for separate cleaning, which solves the problem of incomplete cleaning.

[0033] The central tube 8 and the carrier gas preheating tube 10 are welded together as a whole. The central tube 8 passes through the central opening on each layer of the source plate, and its top end is connected to the flange 7 through a thread. The support plate 13 at the welding point of the central tube 8 and the carrier gas preheating tube 10 tightly contacts the source plate together; the carrier gas preheating tube 10 supports the source plate.

[0034] like Figure 2As shown, the external heating method is to set a carrier gas preheating tube 10 outside the storage container 3. The carrier gas preheating tube 10 is a spiral coil. The inlet of the carrier gas preheating tube is connected to the carrier gas pipeline, and the outlet is connected to the bottom tube 4. The bottom tube 4 is inserted into the bottom of the storage container. An arc-shaped buffer groove 14 is provided on the bottom plate of the storage container opposite to the bottom tube; the carrier gas preheating tube 10 is provided with a heating unit. The carrier gas is first heated to the same temperature as the storage container by the carrier gas preheating tube 10, and then enters the chamber of the storage container. Compared with the internal heating method, the advantage of the external heating method is that its structure is simple, the carrier gas preheating tube can adopt a separate heating setting according to actual use, and its length can also be controlled. The disadvantage is that the external carrier gas preheating tube increases the use space, and there are certain requirements for the equipment used when using it.

[0035] When applied, such as Figure 1 , high-purity solid sources (metal chlorides, trimethyl indium, magnesium cyclopentadienyl or carbon tetrabromide, etc., with a purity of ≥99.9999%) with a particle diameter of 2 to 3 mm are respectively filled in the multi-layer source carrier plate 11, which is firmly attached to the thread at the upper end of the central tube 8 and the support plate 13 at the lower end. There are card slots between the source carrier plates to prevent gas leakage. When in use, the valve group 6 is in an open state, and the heating sleeve heats the bottle body. The carrier gas enters from the carrier gas inlet pipe 1, along the central tube 8, and enters the carrier gas preheating pipe 10. After passing through the carrier gas preheating pipe 10 of about 1.2 meters, the low-temperature carrier gas is heated to the same temperature as the cylinder; the heated carrier gas enters the next layer of the source carrier plate along the connecting pipe, and after carrying the steam transformed from the solid source, it enters the upper layer of the partition along the connecting pipe. The source steam in the carrier gas is gradually saturated, and finally enters the inside of the use equipment through the outlet pipe 5.

[0036] like Figure 2 , high-purity solid sources (metal chlorides, metal organic compounds such as trimethyl indium, bismuth magnesium or other solid compounds such as carbon tetrabromide, etc., with a purity of ≥99.9999%), are respectively filled in storage containers (steel cylinders) 3. When in use, the valve group is in an open state, the heating sleeve heats the outer bottle body, and the carrier gas enters through the carrier gas preheating tube 10 of about 1.2 meters, and the temperature is increased. The low-temperature carrier gas is heated to the same temperature as the steel cylinder and enters the bottle body along the bottom insertion tube 4. The solid source in the bottle body becomes steam, and the source steam in the carrier gas is gradually saturated, and finally enters the inside of the use equipment through the outlet pipe 5.

[0037] The solid source is uniformly filled in the multi-layer source carrier plate 11 by adopting the mode of one bottle and multiple layers, replacing the traditional one-bottle-one-cavity steel bottle form. The contact mode between the carrier gas and the source is changed from point contact to homogeneous contact, which significantly lengthens the path of the carrier gas through the solid source. Due to the preheating effect of the carrier gas preheating tube 10, the source steam brought out is more stable; not only the utilization rate of the solid source is improved, but also the stability of the steam is improved, providing support for the stability of the semiconductor process; at the same time, since the bottle body is a source carrier plate structure, it is easy to disassemble and clean, and there is no dead corner. The cost is low and suitable for large-scale promotion and application.

[0038] Example 1

[0039] Take 100g of high-purity aluminum chloride particles with a diameter of 1-3mm in a steel cylinder with internal heating, and evenly load them into five layers of carrier plates, 20g per layer. Heat the bottle as required, and do not heat the carrier gas preheating tube. Use high-purity nitrogen as carrier gas, and let the carrier gas flow into the steel cylinder at a constant speed. The opening and closing of the gas line is controlled by a solenoid valve. The carrier gas flows out of the steel cylinder with aluminum chloride and is cooled in a collection tube placed in a cooling tank. Liquid nitrogen is used for cooling. The ventilation timer is 1h, the carrier gas is stopped, the heating of the bottle is stopped, and the weight increase of the collection tube is weighed to obtain 19.32g of aluminum chloride.

[0040] Example 2

[0041] The difference from Example 1 is that the carrier gas preheating tube 10 is heated to 160°C, but the temperature is the same as that of the bottle body. High-purity nitrogen is used as the carrier gas, the carrier gas is introduced into the steel bottle at a constant speed, and the gas circuit is opened and closed by the solenoid valve, the carrier gas flows out of the steel bottle with aluminum chloride, and is cooled in the collection tube placed in the cooling tank. The ventilation timer is 1h, the carrier gas is stopped, the bottle body is stopped from being heated, and the weight of the collection tube is weighed to obtain 23.7g of aluminum chloride.

[0042] Compared with Example 1, the blowing amount of aluminum trichloride in Example 2 increases by 22.7%. Therefore, by preheating the carrier gas, the raw material gas efficiency can be significantly improved compared with the case where the carrier gas is not preheated.

[0043] Example 3

[0044] Using an externally heated steel cylinder, take 30g of high-purity aluminum chloride particles with a diameter of 1 to 3mm and put them into the steel cylinder. Heat the bottle as required, and do not heat the carrier gas preheating tube 10. Use high-purity nitrogen as the carrier gas, and let the carrier gas flow into the steel cylinder at a constant speed. The gas line is opened and closed by the solenoid valve, and the carrier gas flows out of the steel cylinder with aluminum chloride and is cooled in the collection tube placed in the cooling tank. Time and record, stop heating the bottle, weigh the weight added by the collection tube, and obtain the aluminum chloride receiving data, as shown in Table 1.

[0045] Example 4

[0046] The difference from Example 3 is that the carrier gas preheating tube 10 is heated to 160°C, the same temperature as the bottle body. High-purity nitrogen is used as the carrier gas, the carrier gas is introduced into the steel bottle at a constant speed, and the gas circuit is opened and closed by the solenoid valve. The carrier gas carries aluminum chloride out of the steel bottle and is cooled in the collection tube placed in the cooling tank. Timing and recording, stop heating the bottle body, weigh the increased weight of the collection tube, and obtain aluminum chloride receiving data, as shown in Table 1.

[0047] Table 1

[0048]

[0049] Calculated from the data of ventilation for 60 minutes, the blowing amount of aluminum trichloride in Example 4 increased by 81.9% compared with Example 3. Therefore, by preheating the carrier gas, the raw material gas efficiency can be significantly improved compared with the case where the carrier gas is not preheated.

[0050] In summary, the method for improving the efficiency of raw material gas flow of the present invention effectively preheats the carrier gas to reduce the temperature drop of the raw material caused by the normal temperature gas passing through the raw material, thereby avoiding the problem of unstable gas loading. The carrier gas preheating method can be internal heating or external heating. The raw material is evenly dispersed in the multi-layer carrier plate to increase the contact time and area between the gas and the material, thereby increasing the material loading per unit volume.

[0051] Internal heating method, built-in carrier gas preheating tube, a multi-layer carrier source plate structure is provided in the bottle, the carrier gas preheating tube is used to extend the residence time of the gas in the bottle, when the gas is taken in, the carrier gas enters the bottle from the air inlet and is fully heated in the carrier gas preheating tube, thus improving the heat balance in the cylinder and ensuring the stability of the source vapor pressure; and the carrier gas preheating tube has a supporting effect on the carrier source plate.

[0052] External heating method, external carrier gas preheating tube, the carrier gas is first heated to the same temperature as the cylinder through the carrier gas preheating tube, and then enters the cylinder through the bottom tube.

[0053] The bottle of the internal heating method is equipped with multiple layers of source plates. After passing through the layers of obstruction of the source plate structure, the carrier gas presents an S-shaped flow in the bottle 4, which greatly increases the contact time with the source, effectively avoids the uneven and unstable air pressure inside the cylinder, and improves the effect of stabilizing the source vapor pressure.

[0054] The multi-layer source-carrying plates in the bottle with internal heating are movable and can be taken out for individual cleaning without dead corners, thus solving the problem of incomplete cleaning.

[0055] It is equipped with pneumatic valves, which is conducive to automatic control. It is connected through VCR interface and flange, which is easy to disassemble and replace, and there is no need to worry about pipeline blockage.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention. It should be noted that similar numbers and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0057] The above is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0058] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

Claims

1. A method for improving the efficiency of raw gas volume, characterized in that: The carrier gas in contact with the source in the storage container is preheated to stabilize the thermal equilibrium in the storage container and the vapor pressure of the source; The carrier gas is preheated by an internal heating method, wherein a carrier gas preheating tube is arranged in the storage container, the inlet of the carrier gas preheating tube is connected to the carrier gas inlet tube, the outlet is connected to the chamber of the storage source, and the storage container is placed in the heat source; The internal heating method is as follows: the carrier gas preheating pipe is arranged at the bottom end of the storage container, and the storage container is provided with multiple layers of movable source-carrying plates, which divide the inner cavity of the storage container from bottom to top into multiple chambers, and each layer of source-carrying plates is provided with a connecting pipe for connecting the upper chamber with the lower chamber, and each layer of source-carrying plates is also provided with a central hole for the central tube to be plugged in, and the central tube passes through each layer of source-carrying plates, and its top end is connected with the carrier gas inlet pipe, and its bottom end is connected with the carrier gas preheating pipe, and the outlet of the carrier gas preheating pipe is located in the chamber where the carrier gas preheating pipe is located, and the air outlet pipe is connected with the uppermost chamber; the carrier gas enters the central pipe through the carrier gas inlet pipe, and then the carrier gas enters the chamber after being preheated by the carrier gas preheating pipe, and passes through the connecting pipe of each layer of source-carrying plates from bottom to top in turn with the source steam, and finally forms saturated steam and is transported out from the air outlet pipe, and the carrier gas is preheated through the carrier gas preheating pipe, so as to avoid uneven air intake and unstable air pressure inside the container, and improve the utilization rate of the source; The carrier gas preheating tube is a spiral coil; Each source carrier plate is provided with a central opening and two connecting pipes, which are radially located on a straight line, and the two connecting pipes are bilaterally symmetrical with the central opening as the center. The connecting line between the connecting pipe and the central opening on each source carrier plate and the connecting line between the connecting pipe and the central opening on the adjacent source carrier plate are perpendicular to each other in axial projection; The central tube is welded to the carrier gas preheating tube as a whole, and the central tube passes through the central opening on each layer of the source carrier plate, and the top end is connected to the flange through a thread. The support plate at the welding point of the central tube and the carrier gas preheating tube tightly contacts the source carrier plate together.

2. The method for improving the efficiency of raw gas quantity according to claim 1, characterized in that: The inlet of the air outlet pipe is provided with a filter.

3. The method for improving the efficiency of raw gas quantity according to claim 1, characterized in that: The outlet of the carrier gas preheating tube is located at the bottom of the chamber where the carrier gas preheating tube is located.

4. The method for improving the efficiency of raw gas quantity according to claim 1, characterized in that: The source carrier plate has 2 to 8 layers, which are arranged at intervals from bottom to top.

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