阅读说明：本技术 一种基于高温常压微波等离子体的材料合成系统 (Material synthesis system based on high-temperature normal-pressure microwave plasma ) 是由 白野 李大帅 于 2020-07-02 设计创作，主要内容包括：本发明公开了一种基于高温常压微波等离子体的材料合成系统,在高温常压微波等离子体炬产生系统中,通过引燃控制电极靠近中空导体输出端,在大功率微波作用下出现尖端击穿,通过中心导体输出的携带前驱材料的载气流,在大功率微波作用下产生尖端放电,形成稳定的高温常压等离子体炬。前驱材料经高温常压微波等离子炬裂解为活化粒子束流,为材料生长合成提供所需活化粒子。在材料生长及控制系统中,金属环与引燃控制电极在外部可调直流电源的控制下,在材料生长区域形成可调的静电场分布,活化粒子束流在可调的静电场作用下改变其运动状态,从而控制活化粒子束流中的正负离子、电子或粒子的运动速度或成分比例,实现材料生长过程的可控,解决了生长控制力弱的问题。(In a high-temperature normal-pressure microwave plasma torch generating system, a control electrode is ignited to be close to the output end of a hollow conductor, tip breakdown occurs under the action of high-power microwave, and tip discharge is generated under the action of high-power microwave through carrier gas flow which is output by a central conductor and carries precursor materials, so that a stable high-temperature normal-pressure plasma torch is formed. The precursor material is cracked by a high-temperature normal-pressure microwave plasma torch into an activated particle beam, so that the required activated particles are provided for the growth and synthesis of the material. In the material growth and control system, the metal ring and the ignition control electrode form adjustable electrostatic field distribution in a material growth area under the control of an external adjustable direct current power supply, and the motion state of the activated particle beam is changed under the action of the adjustable electrostatic field, so that the motion speed or component proportion of positive and negative ions, electrons or particles in the activated particle beam is controlled, the control of the material growth process is realized, and the problem of weak growth control force is solved.)

1. A material synthesis system based on high-temperature normal-pressure microwave plasma is characterized by comprising a high-temperature normal-pressure microwave plasma torch generation system and a material growth and control system;

the high-temperature normal-pressure microwave plasma torch generating system comprises a high-power microwave source, an input coupling transmission system and a plasma torch generating head, wherein the plasma torch generating head consists of a section of hollow conductor and an ignition control electrode, precursor carrier gas is input into one end (input end) of the hollow conductor, precursor carrier gas is output from the other end (output end) of the hollow conductor, and the ignition control electrode is positioned at the output end of the hollow conductor and can move;

in the high-power microwave source and input coupling transmission system, the high-power microwave source couples the output high-power microwave input to the output end of the hollow conductor of the plasma torch generating head, when the material synthesis system is started, the ignition control electrode of the plasma torch generating head is close to the output end of the hollow conductor of the plasma torch generating head, tip breakdown occurs under the action of high-power microwave, and the ignition control electrode is pulled away after the tip breakdown and is arranged in a material growth area; a stable high-temperature normal-pressure plasma torch is formed by the carrier gas precursor output by the central conductor through an avalanche effect under the action of point discharge and high-power microwave excitation;

the material growth and control system comprises a sealing system and a material growth control system, wherein the output end of a hollow conductor of a plasma torch generating head is inserted into the sealing system, an ignition control electrode is also arranged in the sealing system, and the material growth control system consists of a metal ring, an external adjustable direct-current power supply and the ignition control electrode of the plasma torch generating head;

the metal ring is arranged on a sealing system at the output end of a hollow conductor of a plasma torch generating head, an external adjustable direct current power supply is respectively connected with the metal ring and an ignition control electrode of the plasma torch generating head, adjustable electrostatic field distribution is formed in a material growing region in the sealing system under the control of the external adjustable direct current power supply, a precursor is cracked into an activated particle beam by a high-temperature normal-pressure microwave plasma torch, the moving state of the activated particle beam is changed under the action of an adjustable electrostatic field, and therefore the moving speed or the component proportion of positive and negative ions, electrons or particles in the activated particle beam is controlled, and the control of the material growing process is achieved.

2. The material synthesis system based on high-temperature atmospheric-pressure microwave plasma as claimed in claim 1, wherein the main body of the input coupling transmission system is a cylindrical coaxial metal structure with one closed end and the other open end, and can couple the high-power microwave input to the output end of the hollow conductor of the plasma torch generating head, and the high-power microwave input comprises a coaxial outer conductor and a coaxial inner conductor;

the coaxial inner conductor is a hollow cylindrical metal tube, one end of the coaxial inner conductor is connected with a carrier gas source through a closed end and is an input channel of carrier gas, and the other end of the coaxial inner conductor is communicated with the input end of the hollow conductor of the plasma torch generating head;

one side of the coaxial outer conductor close to the closed end is provided with a hole, and a coaxial connector which can be connected with a high-power microwave source output head is arranged; the inner conductor of the coaxial connector extends into the cylindrical coaxial metal structure and is connected with the coaxial inner conductor in the cylindrical coaxial metal structure; the inner conductor and the outer conductor of the coaxial connector are respectively in good electric contact with the coaxial inner conductor and the coaxial outer conductor of the cylindrical coaxial metal structure, and input high-power microwaves are transmitted to the opening end between the coaxial inner conductor and the coaxial outer conductor of the cylindrical coaxial metal structure along the axis, so that the high-efficiency stable input coupling and transmission functions of the high-power microwaves are realized.

3. The high temperature atmospheric pressure microwave plasma-based material synthesis system of claim 1, wherein the ignition control electrode is on an extension of an output end of an inner conductor of a plasma torch generation head, and a hollow conductor of the plasma torch generation head is shorter in length than the outer conductor.

4. The high temperature atmospheric pressure microwave plasma-based material synthesis system of claim 1, wherein the high temperature atmospheric pressure microwave plasma torch generation system further comprises a torch confinement and shielding gas film formation and water circulation insulation system, consisting of a torch confinement and shielding gas film formation section and a water circulation insulation section;

the torch restraining and protective gas film forming part is as follows: an atmosphere gas injection hole is formed in the position, close to the closed end, of the coaxial outer conductor of the cylindrical coaxial metal structure along the tangential direction of the wall of the coaxial outer conductor, the atmosphere gas injection hole is connected with an external atmosphere gas source through a metal conduit, the external atmosphere gas source inputs atmosphere gas with a certain flow rate through the atmosphere gas injection hole according to the material synthesis requirement under the control of a flow controller, and gas flow columns moving towards the inside are formed among the coaxial inner conductor and the coaxial outer conductor of the cylindrical coaxial metal structure and between the hollow conductor of a plasma torch generating head and the coaxial outer conductor of the cylindrical coaxial metal structure; the airflow column is a protective gas mold of the inner wall of the coaxial outer conductor of the cylindrical coaxial metal structure.

The water circulation heat insulation part comprises: a hollow coaxial cylindrical metal cavity is additionally arranged outside the coaxial outer conductor in the direction of the open end of the cylindrical coaxial metal structure; the hollow coaxial cylindrical metal cavity and the coaxial outer conductor are connected into a whole, the inner diameter of the hollow coaxial cylindrical metal cavity is the same as the outer diameter of the coaxial outer conductor, and the outer side wall of the hollow coaxial cylindrical metal cavity close to one side of the open end of the cylindrical coaxial metal structure is a ring which is used as a sealing flange baffle plate and is used for sealing a material growth area; two metal small holes are arranged on the hollow coaxial cylindrical metal cavity and connected with an external water circulation system, and the high-power microwave source and the input coupling transmission system are thermally isolated from the high-temperature normal-pressure plasma torch and the material growth area.

5. The material synthesis system based on high-temperature atmospheric-pressure microwave plasma according to claim 1, characterized in that the sealing system is composed of a section of quartz glass tube, two water jacket flanges, two baffles, a vacuum pump and a vacuum tester;

the inner cavity of the quartz glass tube is a material growth area, and the water jacket flanges are sleeved at two ends of the quartz glass tube; the opening end part of the cylindrical coaxial metal structure is inserted into the front end of the quartz glass tube; the two baffles are respectively arranged at two ends of the quartz glass tube, so that the quartz glass tube forms a closed material growth area; the vacuum pump and the vacuum tester are connected with the material growth area through two small holes on a water jacket flange at the tail end of the quartz glass tube, one small hole is connected with a gas pipeline of the vacuum pump, and the other small hole is inserted into a probe of the vacuum tester; in addition, a small hole is also formed on the water jacket flange at the tail end of the quartz glass tube, is a tail gas discharge hole in the material growth period and is connected with a tail gas collector; a small hole is formed in the center of a baffle at the tail end of the quartz glass tube, and the ignition control electrode is inserted into a material growth area in the quartz glass tube through the small hole;

the baffle at the front end of the quartz glass tube is a circular ring at one side of the hollow coaxial cylindrical metal cavity close to the open end of the cylindrical coaxial metal structure.

6. The system for synthesizing materials based on microwave plasma under high temperature and normal pressure as claimed in claim 1, wherein the system for growing and controlling materials further comprises a temperature distribution control system, a concentric cylinder heating system is installed on the outer wall of the quartz glass tube as the temperature distribution control system, and the temperature according with the growth of materials is generated in the material growth area; the concentric cylinder heating system heats uniformly along the circumferential direction of the quartz glass tube, can provide a certain temperature gradient along the axial direction of the quartz glass tube, and has a temperature control range of 100-1500 ℃; the concentric cylinder heating system can move axially along the quartz glass tube according to the growth requirement of the material.

Technical Field

The invention belongs to the technical field of microwave plasma and material synthesis, and particularly relates to a material synthesis system based on high-temperature normal-pressure microwave plasma, namely a technology for synthesizing a new material by using a high-temperature normal-pressure microwave plasma torch.

Background

The development of novel materials is always a research hotspot of leading-edge science. The novel structural material represented by zero-dimensional, one-dimensional and two-dimensional nano materials is an object traced by people by excellent mechanical, electrical and thermal properties, is an indispensable foundation for next-generation information systems, energy storage systems and coating materials, and has attractive application prospects in the aspects of high speed, low energy consumption, large-scale components and novel sensors. Meanwhile, the solar energy and storage battery have excellent performances, so that the high-efficiency clean energy and long-endurance electric system becomes possible.

The excellent performance of the high-performance three-dimensional material in the aspects of hardness and heat conduction is a transmission contact surface material which is urgently needed in a high-speed rotating system structure, and the application of the high-performance three-dimensional material in the aspects of aviation and aerospace engine bearings and blades can greatly improve the performance and prolong the service life.

At present, the preparation of novel materials is still mainly prepared by a chemical method. For example, the conventional CVD (Chemical vapor deposition) method is a material preparation method based on the Chemical activation vacuum deposition technique. In addition, the preparation methods of high-temperature normal-pressure sputtering deposition, direct-current vacuum plasma and the like are available. Both of the above techniques have certain problems in the preparation of novel materials. For example, in the aspect of graphene preparation, most methods can only prepare micron-sized powder single-crystal graphene, and large-piece low-defect graphene is extremely difficult to synthesize, so that the application level and range of the graphene are limited. Some materials are difficult to crack due to large molecular bond energy, and active particles are difficult to obtain by the conventional method at present and are difficult to serve as precursors of novel materials.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a material synthesis system based on high-temperature normal-pressure microwave plasma, so as to solve the problems of difficult precursor cracking and activation, weak growth control capability and low energy efficiency in material synthesis and realize the rapid synthesis of novel materials by using precursors with different forms and different types.

In order to achieve the aim, the material synthesis system based on the high-temperature normal-pressure microwave plasma is characterized by comprising a high-temperature normal-pressure microwave plasma torch generation system and a material growth and control system;

the high-temperature normal-pressure microwave plasma torch generating system comprises a high-power microwave source, an input coupling transmission system and a plasma torch generating head, wherein the plasma torch generating head consists of a section of hollow conductor and an ignition control electrode, precursor carrier gas is input into one end (input end) of the hollow conductor, precursor carrier gas is output from the other end (output end) of the hollow conductor, and the ignition control electrode is positioned at the output end of the hollow conductor and can move;

in the high-power microwave source and input coupling transmission system, the high-power microwave source couples the output high-power microwave input to the output end of a hollow conductor in a plasma torch generating head; when the material synthesis system is started, an ignition control electrode of a plasma torch generating head is close to the output end of a hollow conductor of the plasma torch generating head, tip breakdown occurs under the action of high-power microwave, the ignition control electrode is extracted after the tip breakdown and is placed in a material growth area, and a stable high-temperature normal-pressure plasma torch is formed through an avalanche effect under the action of tip discharge and high-power microwave excitation through precursor carrier gas output by a central conductor;

the plasma torch generating head comprises a hollow conductor, an ignition control electrode and a material growth and control system, wherein the material growth and control system also comprises a sealing system and a material growth and control system; the material growth control system consists of a metal ring, an external adjustable direct current power supply and an ignition control electrode of a plasma torch generating head;

the metal ring is arranged on the outer wall of the sealing system at the output end of the hollow conductor in the plasma torch generating head; an external adjustable direct current power supply is respectively connected with the metal ring and an ignition control electrode of a plasma torch generating head, and adjustable electrostatic field distribution is formed in a material growth area in the sealing system under the control of the external adjustable direct current power supply; the precursor is cracked into an activated particle beam by a high-temperature normal-pressure microwave plasma torch, and the motion state of the activated particle beam is changed under the action of an adjustable electrostatic field, so that the motion speed or the component proportion of positive and negative ions, electrons or particles in the activated particle beam is controlled, and the control of the growth process of the material is realized.

The invention aims to realize the following steps:

the invention relates to a material synthesis system based on high-temperature normal-pressure microwave plasma, which comprises a high-temperature normal-pressure microwave plasma torch generation system and a material growth and control system. In a high-temperature normal-pressure microwave plasma torch generating system, a control electrode is ignited to be close to the output end of a hollow conductor, so that the output end of the hollow conductor is subjected to tip breakdown under the action of high-power microwaves, a stable high-temperature normal-pressure plasma torch is formed through tip discharge and high-power microwave excitation by a precursor (along with precursor carrier gas, namely precursor carrier gas flow carrying the precursor), and the precursor is cracked into an activated particle beam by the high-temperature normal-pressure microwave plasma torch, so that the problem of difficulty in cracking and activating the precursor in material synthesis is solved. In the material growth and control system, the metal ring and the ignition control electrode form adjustable electrostatic field distribution in a material growth area under the control of an external adjustable direct current power supply, and the motion state of the activated particle beam is changed under the action of the adjustable electrostatic field, so that the motion speed or component proportion of positive and negative ions, electrons or particles in the activated particle beam is controlled, the control of the material growth process is realized, and the problem of weak growth control force is solved. In addition, the energy efficiency of the invention is greatly improved.

Drawings

FIG. 1 is a schematic structural diagram of one embodiment of a high temperature and atmospheric pressure microwave plasma-based material synthesis system of the present invention;

FIG. 2 is a schematic diagram of the high temperature and atmospheric pressure microwave plasma torch generation system of FIG. 1;

fig. 3 is a schematic structural diagram of the material growth and control system shown in fig. 2.

Detailed Description

The following description of the embodiments of the present invention is provided in order to better understand the present invention for those skilled in the art with reference to the accompanying drawings. It is to be expressly noted that in the following description, a detailed description of known functions and designs will be omitted when it may obscure the subject matter of the present invention.

FIG. 1 is a schematic structural diagram of an embodiment of a material synthesis system based on high-temperature atmospheric-pressure microwave plasma according to the present invention.

In this embodiment, as shown in fig. 1, the material synthesis system based on high temperature and normal pressure microwave plasma of the present invention includes two major parts, namely, a high temperature and normal pressure microwave plasma torch generation system and a material growth and control system (divided by a thick black solid line, the left side is the high temperature and normal pressure microwave plasma torch generation system, and the right side is the material growth and control system.

The high-temperature normal-pressure microwave plasma torch generating system cracks a precursor for material growth by using the high-temperature normal-pressure microwave plasma torch to form a particle source for material growth, and particles of the particle source enter a growth area under the drive of airflow. Forming a material growth condition under the action of a temperature control system and a material growth control system, and synthesizing a target material.

1. High-temperature normal-pressure microwave plasma torch generating system

The high-temperature normal-pressure microwave plasma torch generating system is used for generating a high-temperature normal-pressure microwave plasma torch, and by the characteristics of thousands of degrees centigrade high temperature, high-frequency electromagnetic oscillation and the like, precursors with different forms, different types and different structures can be quickly cracked into activated particle beams consisting of atoms, molecules, ions, electrons or molecular groups, so that a sufficient and controllable particle source is provided for material growth (synthesis).

In this embodiment, as shown in fig. 2, the high-temperature normal-pressure microwave plasma torch generating system further comprises a high-power microwave source and input coupling transmission system, a plasma torch generating head, and a torch restraining and shielding gas film forming and water circulation heat insulation system.

1) High-power microwave source and input coupling transmission system

In the present embodiment, as shown in fig. 2, in the high-power microwave source and the input coupling transmission system, the high-power microwave source couples and transmits the output high-power microwave (tens to thousands of kilowatts) to the output end of the hollow conductor of the plasma torch generating head.

The high-power microwave source and the input coupling transmission system consist of a high-power microwave source and an input coupling transmission system. In this embodiment, the high-power microwave source is a high-power solid-state source or an electric vacuum source (such as a magnetron) with a frequency of 2.45GHz or 0.915GHz, and can output high-power microwaves of several watts to tens of kilowatts, and the output power is adjustable. The input coupling transmission system main body is a cylindrical coaxial metal structure with one closed end and the other open end, can couple the output microwave input of the high-power microwave source to the output end of a hollow conductor of a plasma torch generating head, and comprises a coaxial outer conductor 10 and a coaxial inner conductor 11; the coaxial inner conductor 11 is a hollow cylindrical metal tube, one end of the coaxial inner conductor is connected with a carrier gas source through a closed end and is an input channel of carrier gas, and the other end of the coaxial inner conductor is communicated with the input end of the hollow conductor 12 of the plasma torch generating head. One side of the coaxial outer conductor 10 close to the closed end is provided with a hole, and a coaxial connector 13 which can be connected with a high-power microwave source output head is arranged; the inner conductor of the coaxial connector 13 extends into the cylindrical coaxial metal structure and is connected with the coaxial inner conductor 11 in the cylindrical coaxial metal structure; the inner conductor and the outer conductor of the coaxial connector are respectively in good electric contact with the coaxial inner conductor 11 and the coaxial outer conductor 10 of the cylindrical coaxial metal structure; the input high-power microwave is transmitted to the opening end along the axis between the coaxial inner conductor 11 and the coaxial outer conductor 10 of the cylindrical coaxial metal structure, so that the high-power microwave is efficiently and stably input and coupled and transmitted. In this embodiment, the coaxial connector 13 is a coaxial connector of L16 or L32

2) Plasma torch generating head

The plasma torch generating head is composed of a section of hollow conductor 12 and an ignition control electrode 14, wherein one end (input end) of the hollow conductor 12 inputs precursor carrier gas, the other end (output end) outputs precursor carrier gas, and the ignition control electrode 14 is positioned at the output end of the hollow conductor 12 and can move. In this embodiment, the ignition control electrode 14 is on an extension of the output end of the hollow conductor 12, and the hollow conductor of the torch generating head is shorter in length than the outer conductor.

In the present embodiment, as shown in fig. 2, the hollow conductor 12 is a hollow cylindrical metal tube, and is connected with the coaxial inner conductor 11 as a whole; the length of the coaxial inner conductor 11 and the hollow conductor 12 connected together is smaller than the length of the coaxial outer conductor 10. Thus, the high-power microwave is transmitted to the opening end along the axis between the coaxial inner conductor 11 and the coaxial outer conductor 10 and between the hollow conductor 12 and the coaxial outer conductor 10, and a cut-off waveguide structure, namely a cut-off transmission line, is formed at the output end of the hollow conductor 12 to prevent the microwave from leaking; meanwhile, the high-power microwave source can couple the output high-power microwave to the output end of the hollow conductor 12 of the plasma torch generating head; when the material synthesis system is started, the ignition control electrode 14 of the plasma torch generating head is close to the output end of the hollow conductor 12 of the plasma torch generating head, tip breakdown occurs under the action of high-power microwave, the ignition control electrode 14 is drawn out after the tip breakdown and is placed in a material growth area, and a stable high-temperature normal-pressure plasma torch is formed through avalanche effect under the action of tip discharge and high-power microwave excitation through a precursor (along with precursor carrier gas) output by the central conductor 12.

When the precursor gas is used as carrier gas, the precursor gas is cracked into active particle beam in a high-temperature normal-pressure microwave plasma torch; when the precursor fluid is added, the precursor fluid is mixed with carrier gas flow and is cracked into active particle beam flow in a high-temperature normal-pressure microwave plasma torch; when the precursor is solid, the precursor is prepared into a hollow cylinder with the same radial size as the hollow conductor, placed at the output end of the hollow conductor, and cracked into an active particle beam by a high-temperature normal-pressure microwave plasma torch.

3) Torch restraint and protective gas film formation and water circulation heat insulation system

In this embodiment, the high-temperature normal-pressure microwave plasma torch generation system further comprises a torch confinement and protective gas film formation and water circulation heat insulation system, and the torch confinement and protective gas film formation part and the water circulation heat insulation part form the torch confinement and protective gas film formation system.

The torch restraining and protective gas film forming part is as follows: an atmosphere gas injection hole 15 is formed in the position, close to the closed end, of the coaxial outer conductor 10 of the cylindrical coaxial metal structure along the tangential direction of the wall of the coaxial outer conductor 10, and the atmosphere gas injection hole 15 is connected with an external atmosphere gas source through a metal pipe; inputting atmosphere gas with a certain flow rate through an atmosphere gas injection hole 15 under the control of a flow controller according to the material synthesis requirement by an external atmosphere gas source, and forming gas flow columns moving towards an opening end between the coaxial inner conductor 11 and the coaxial outer conductor 10 of the cylindrical coaxial metal structure and between the hollow conductor 12 of the plasma torch generating head and the coaxial outer conductor 10 of the cylindrical coaxial metal structure; the airflow column is a protective gas mold of the inner wall of the coaxial outer conductor 10 of a cylindrical coaxial metal structure, so that the high-temperature normal-pressure plasma torch and the coaxial outer conductor 10 are prevented from being punctured, and meanwhile, the thermal insulation effect is achieved, and the inner wall of the coaxial outer conductor 10 is protected from being ablated by high temperature; the gas flow column also restrains the high-temperature normal-pressure plasma torch in a certain area so as to form a stable high-temperature normal-pressure plasma torch and crack the precursor into an activated particle beam. In this embodiment, the atmosphere gas is hydrogen.

The water circulation heat insulation part comprises: a hollow coaxial cylindrical metal cavity 16 is additionally arranged on the coaxial outer conductor 10 in the direction of the open end of the cylindrical coaxial metal structure. The hollow coaxial cylindrical metal cavity 16 is connected with the coaxial outer conductor 10 into a whole, the inner diameter of the hollow coaxial cylindrical metal cavity 16 is the same as the outer diameter of the coaxial outer conductor 10, and the outer side wall of the hollow coaxial cylindrical metal cavity 16 close to one side of the open end of the cylindrical coaxial metal structure is a ring which is used as a sealing flange baffle plate 17 and is used for sealing a material growth area; two metal small holes are arranged on the hollow coaxial cylindrical metal cavity 16 and are connected with an external water circulation system, and a high-power microwave source and an input coupling transmission system are thermally isolated from a high-temperature normal-pressure plasma torch and a material growth area.

2. Material growth and control system

The material synthesis needs to keep a pure atmosphere according to requirements, a synthesis area needs to be sealed, the temperature distribution can be controlled, the vacuum can be drawn, and meanwhile, the concentration and the movement speed of the activated particle beam after the precursor needed by synthesis is cracked can be controlled according to the material synthesis requirements.

In this embodiment, as shown in fig. 3, the material growth and control system further includes a sealing system, a temperature distribution control system, and a material growth control system.

2.1), sealing systems

In this embodiment, the sealing system is constituted by a length of quartz glass tube 20, two water jacket flanges 21, 22, two baffles 17, 23, and a vacuum pump and vacuum tester. The inner cavity of the quartz glass tube 20 is a material growth area, and the water jacket flanges 21 and 22 are sleeved at two ends of the quartz glass tube 20; the open end portion of the cylindrical coaxial metal structure is inserted into the front end of the quartz glass tube 20 so that the coaxial outer conductor 10, the output end of the hollow conductor 12 of the plasma torch generating head, is inserted into the sealed system; two baffles 17 and 23 are respectively arranged at two ends of the quartz glass tube 20, so that the quartz glass tube 20 forms a closed material growth area; the vacuum pump and the vacuum tester are connected with the material growth area through two small holes on a water jacket flange 22 at the tail end of the quartz glass tube 20, one small hole is connected with a gas pipeline of the vacuum pump, and the other small hole is inserted into a probe of the vacuum tester; in addition, a small hole is formed on the water jacket flange 22 at the end of the quartz glass tube 20, which is a tail gas discharge hole during the material growth and is connected with a tail gas collector, a small hole is formed in the center of the baffle plate 23 at the end of the quartz glass tube 20, and the ignition control electrode 14 is inserted into the material growth area in the quartz glass tube 20 through the small hole.

The baffle 17 at the front end of the quartz glass tube 20 is a circular ring at one side of the hollow coaxial cylindrical metal cavity 16 close to the open end of the cylindrical coaxial metal structure. The front end water jacket flange 21 further thermally isolates the high-power microwave source and the input coupling transmission system from the high-temperature normal-pressure plasma torch and a material growth area, so that the high-power microwave source and the input coupling transmission system are prevented from being damaged by high temperature; the end water jacket flange 22 insulates the material growth region from the rest of the system and provides protection from cooling. The two water circulation holes of the water jacket flanges 21 and 22 are connected with an external water circulation system, so that the protection function of heat insulation and temperature reduction is achieved.

Thus, the output end of the torch generating head is inserted into the sealing system, and the ignition control electrode 14 is also placed in the sealing system.

2.2) temperature distribution control System

In the present embodiment, a concentric cylindrical heating system 24 is installed on the outer wall of the quartz glass tube 20 as a temperature distribution control system to generate a temperature in accordance with the growth of the material in the material growth region; the concentric cylinder heating system 24 heats uniformly along the circumferential direction of the quartz glass tube 20, and can provide a certain temperature gradient along the axial direction of the quartz glass tube 20, and the temperature control range is 100-1500 ℃; the concentric cylindrical heating system 24 can be moved axially along the quartz glass 20 tube as required for material growth.

2.3) Material growth control System

The material growth control system consists of a metal ring 25, an external adjustable dc power supply (not shown) and the ignition control electrode 14 of the torch generating head.

In this embodiment, the metal ring 25 is placed on the outer wall of the quartz glass tube 20 at the output end of the hollow conductor 12 in the plasma torch generating head, i.e. on the sealing system; an external adjustable direct current power supply is respectively connected with the metal ring 25 and the ignition control electrode 14 of the plasma torch generating head; forming adjustable electrostatic field distribution in a material growth region in a sealing system (quartz glass tube) under the control of an external adjustable direct current power supply; the precursor is cracked into an activated particle beam by a high-temperature normal-pressure microwave plasma torch, and the motion state of the activated particle beam is changed under the action of an adjustable electrostatic field, so that the motion speed or the component proportion of positive and negative ions, electrons or particles in the activated particle beam is controlled, and the control of the growth process of the material is realized.

In this embodiment, as shown in FIG. 3, the material growth area is provided with a substrate 26 for material growth.

The invention utilizes the high-frequency electromagnetic oscillation of high-power microwave to crack molecules or atoms to form a high-temperature normal-pressure plasma torch, thereby realizing the generation of a particle source for material growth. The highest temperature of the high-temperature normal-pressure plasma torch is close to 5000 ℃, high-frequency electromagnetic oscillation is added, most of the current materials can be cracked, an activated particle beam current existing in a plasma mode is formed, and necessary conditions are provided for growth and synthesis of the materials. Meanwhile, the motion of the charged particle source is controlled by the density, temperature, flow rate and component control of the activated particle beam, the distribution design and strength of an external electric field, the growth process of the novel material is controlled, the controllable growth of the material is realized, and the problems of controllability and the like in the growth stage of the material are solved.

Before the material synthesis system based on the high-temperature normal-pressure microwave plasma is started, a carrier gas source, an atmosphere gas source, a high-power microwave source, an external water circulation system, an external adjustable direct-current power supply, a vacuum pump, a vacuum tester and a tail gas collector are connected to the system. Opening a vacuum pump, and pumping air in the sealed system (quartz glass tube); when the vacuum tester displays proper vacuum degree, the pipeline switches of the carrier gas source and the atmosphere gas source are opened, and carrier gas and atmosphere gas are input; when the air pressure in the sealing system is close to the normal pressure, the vacuum pump is turned off, and a pipeline switch of the tail gas collector is turned on; at the moment, a temperature control switch of the concentric cylinder heating system is turned on, the temperature of the material growth area is heated to a set value, and an external water circulation system is turned on at the same time; turning on a high-power microwave source, inputting high-power microwaves, adjusting the flow of atmosphere gas and carrier gas, and observing whether the tail end of the hollow conductor (output end) is punctured with the ignition control electrode through the wall of the quartz glass tube; once breakdown occurs, the ignition control electrode is immediately pulled away and placed in a material growth area, an external adjustable direct current power supply outputs adjustable direct current voltage, direct current bias voltage is loaded to the metal ring and the ignition control electrode, and the flow speed and the density of an activated particle beam are controlled; when the growth time is set, the high-power microwave source, the concentric cylinder heating system and the carrier gas source are sequentially turned off; and when the temperature is reduced to the normal temperature, the atmosphere gas source and the external water circulation system are turned off, the water jacket flange is opened, and the synthetic material substrate is taken out to complete material synthesis.

Although illustrative embodiments of the present invention have been described above to facilitate the understanding of the present invention by those skilled in the art, it should be understood that the present invention is not limited to the scope of the embodiments, and various changes may be made apparent to those skilled in the art as long as they are within the spirit and scope of the present invention as defined and defined by the appended claims, and all matters of the invention which utilize the inventive concepts are protected.