CN112235930B

CN112235930B - Measuring device for interaction of glow discharge plasma and microwave waveguide

Info

Publication number: CN112235930B
Application number: CN202011078560.0A
Authority: CN
Inventors: 袁承勋; 周晨; 李辉; 姚静锋; 周忠祥; 吴健
Original assignee: Harbin Institute of Technology; China Research Institute of Radio Wave Propagation CRIRP
Current assignee: Harbin Institute of Technology; China Research Institute of Radio Wave Propagation CRIRP
Priority date: 2020-10-10
Filing date: 2020-10-10
Publication date: 2022-09-23
Anticipated expiration: 2040-10-10
Also published as: CN112235930A

Abstract

The invention provides a measuring device for interaction of glow discharge plasma and microwave waveguide, belonging to the field of electromagnetic field. The problem of current microwave and plasma interaction mechanism complicated and research insufficient is solved. It includes microwave generation source, waveguide assembly, quartz capsule, vacuum electrode, vacuum pump, microwave signal receiver and DC power supply, microwave generation source, waveguide assembly and microwave signal receiver pass through the coaxial line and link to each other in proper order, the hole has been seted up to waveguide assembly's cavity both sides, the quartz capsule inserts in waveguide assembly's the cavity through the hole, the quartz capsule both ends are equallyd divide and are do not be provided with vacuum electrode, the last hollow cathode that is provided with of vacuum electrode, the quartz capsule links to each other with the vacuum pump, the vacuum electrode at quartz capsule both ends links to each other with DC power supply's positive negative pole respectively. The method is mainly used for measuring the interaction between the plasma and the microwave waveguide.

Description

Measuring device for interaction of glow discharge plasma and microwave waveguide

Technical Field

The invention belongs to the field of electromagnetic fields, and particularly relates to a measuring device for interaction of glow discharge plasma and microwave waveguide.

Background

Plasma is a multi-particle system composed of a combination of charged particles (positive ions, negative ions, and electrons) and various neutral particles (atoms, molecules, radicals, and reactive groups), the whole being electrically neutral, also commonly referred to as the fourth state of matter. The plasma is generally obtained by heating a gas to break down molecules into atoms and to ionize them. Another common way to obtain plasma is to apply a certain voltage to the gas to ionize it.

There is a very complex interaction between the microwave and the plasma. The microwave heats the plasma, and the plasma can reflect and absorb the microwave. Since the current technological approaches are still imperfect, the problems of plasma reflection and absorption of microwaves still need to be studied and perfected. Therefore, there is an urgent need for a measuring device that can study the interaction between the two and can obtain the correlation result therefrom.

Disclosure of Invention

The invention provides a measuring device for interaction of glow discharge plasma and microwave waveguide, aiming at solving the problems in the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides a glow discharge plasma and microwave waveguide interact's measuring device, it includes microwave generation source, waveguide subassembly, quartz capsule, vacuum electrode, vacuum pump, microwave signal receiver and DC power supply, microwave generation source, waveguide subassembly and microwave signal receiver link to each other in proper order through the coaxial line, the hole has been seted up to waveguide subassembly's cavity both sides, the quartz capsule passes through in the hole inserts waveguide subassembly's cavity, the quartz capsule both ends are equallyd divide and are do not be provided with the vacuum electrode, be provided with hollow cathode on the vacuum electrode, the quartz capsule links to each other with the vacuum pump, the vacuum electrode at quartz capsule both ends links to each other with DC power supply's positive negative pole respectively.

Furthermore, the waveguide assembly is rectangular as a whole, and the interior of the waveguide assembly is divided into an upper cavity and a lower cavity by a metal plate.

Furthermore, 4 holes with the diameter of 25mm are symmetrically formed in the two sides of the upper cavity and the lower cavity of the waveguide assembly, a quartz tube is inserted into each hole, the outer diameter of each quartz tube is 20mm, the wall thickness of each quartz tube is 2mm, the length of each quartz tube is 300mm, and the vacuum degree in each quartz tube is 1 Torr.

Further, a plurality of the quartz tubes on the same side are connected in parallel.

Furthermore, the waveguide assembly is a DC-2 GHz waveguide assembly.

Furthermore, the direct current power supply provides adjustable voltage of 0-1500V.

Furthermore, the hollow cathode is a metal molybdenum sheet with the thickness of 2mm, the diameter of 20mm and the length of 20 mm.

Further, the vacuum electrode is a copper rod with a diameter of 3mm and a length of 52 mm.

Furthermore, an ammeter is connected in series to the direct current power supply, and a voltmeter is connected in parallel to the direct current power supply.

Furthermore, a resistor is connected in series between the vacuum electrode and the direct current power supply.

Compared with the prior art, the invention has the beneficial effects that: the invention solves the problems of complex interaction mechanism and insufficient research of the existing microwave and plasma. The invention adopts glow discharge method to generate plasmas with different densities in the quartz tube by adjusting the voltage of the direct current power supply, thereby realizing the coupling of the plasmas and the microwaves in the waveguide and achieving the purpose of researching the interaction relation between the microwaves and the plasmas with different densities. Meanwhile, the adjustable-frequency microwave generator is used as a microwave source, the interaction relation between microwaves with different frequencies and plasmas is researched, and the research range of the interaction relation between the microwaves and the plasmas is further expanded.

Drawings

FIG. 1 is a schematic structural diagram of a measuring apparatus for interaction between a glow discharge plasma and a microwave waveguide according to the present invention;

FIG. 2 is a schematic view of a waveguide assembly according to the present invention;

fig. 3 is a diagram illustrating the results of numerical simulations of the effects of different sized holes on the transmission characteristics of a waveguide assembly according to the present invention.

The microwave measuring device comprises a microwave generating source 1, a 2-coaxial wire, a 3-waveguide component, a 4-quartz tube, a 5-vacuum electrode, a 6-hollow cathode, a 7-vacuum pump, an 8-microwave signal receiver, a 9-resistor, a 10-direct current power supply, an 11-ammeter and a 12-voltmeter.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely explained below with reference to the drawings in the embodiments of the present invention.

Referring to fig. 1-3 to illustrate the embodiment, a measurement apparatus for interaction between glow discharge plasma and microwave waveguide includes a microwave generation source 1, a waveguide assembly 3, a quartz tube 4, a vacuum electrode 5, a vacuum pump 7, a microwave signal receiver 8 and a dc power supply 10, where the microwave generation source 1, the waveguide assembly 3 and the microwave signal receiver 8 are sequentially connected by a coaxial cable 2, holes are formed on two sides of a cavity of the waveguide assembly 3, the quartz tube 4 is inserted into the cavity of the waveguide assembly 3 through the holes, the vacuum electrode 5 is respectively disposed at two ends of the quartz tube 4, a hollow cathode 6 is disposed on the vacuum electrode 5, the quartz tube 4 is connected with the vacuum pump 7, and the vacuum electrodes 5 at two ends of the quartz tube 4 are respectively connected with the positive and negative poles of the dc power supply 10.

In the embodiment, the microwave generating source 1 outputs the microwave with the target frequency, the microwave is transmitted to the waveguide assembly 3 through the coaxial line 2, and after the microwave interacts with the plasma in the rectangular cavity of the waveguide assembly 3, the microwave continues to be output from the other end of the waveguide assembly 3 and is transmitted to the microwave signal receiver 8 through the coaxial line 2. Finally, the microwave signal receiver 8 converts the received microwave signal into an electrical signal, and outputs and displays the electrical signal.

In this embodiment, the waveguide assembly 3 is rectangular as a whole, and the inside of the waveguide assembly is divided into an upper cavity and a lower cavity by a metal plate, so as to enhance the transmission signal of the microwave on the premise of not affecting the transmission characteristic of the microwave. Two sides of the upper cavity and the lower cavity of the waveguide component 3 are symmetrically provided with 4 holes, and a quartz tube 4 is inserted into each hole. The hole diameter of 25mm does not affect the microwave transmission characteristics of the waveguide assembly 3. The quartz tube 4 is externally connected to a vacuum pump 7, and the degree of vacuum in the quartz tube 4 is controlled within a range suitable for the generation of glow discharge plasma, and the degree of vacuum in the quartz tube 4 is 1 Torr. The quartz tube 4 had an outer diameter of 20mm, a wall thickness of 2mm and a length of 300 mm. The vacuum electrode 5 is a copper bar with the diameter of 3mm and the length of 52mm, and the periphery of the vacuum electrode is sealed by sealant. The hollow cathode 6 is a metal molybdenum sheet with the thickness of 2mm, the diameter of 20mm and the length of 20mm, and aims to generate plasma through ionization outside the cavity of the waveguide component 3 so as to reduce interference generated by microwave transmission inside the cavity of the waveguide component 3. The quartz tubes 4 on the same side are connected in parallel, and the vacuum electrode 5 is connected to the positive and negative electrodes of the direct current power supply 10 in parallel. The waveguide assembly 3 is a DC-2 GHz waveguide assembly. The DC power supply 10 provides an adjustable voltage of 0-1500V. An ammeter 11 is connected in series to the dc power supply 10 in order to visually observe the output current condition of the power supply, and a voltmeter 12 is connected in parallel to the dc power supply 10 in order to visually observe the output voltage condition of the power supply. In order to protect the safety of the experimental device, a resistor 9 is connected in series between the vacuum electrode 5 and the direct current power supply 10.

The interaction measuring device of glow discharge plasma and microwave waveguide provided by the invention is described in detail, and the principle and the implementation mode of the invention are explained by applying specific examples, and the description of the examples is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims

1. A measuring device for interaction of glow discharge plasma and microwave waveguide is characterized in that: the microwave generation device comprises a microwave generation source (1), a waveguide component (3), a quartz tube (4), vacuum electrodes (5), a vacuum pump (7), a microwave signal receiver (8) and a direct current power supply (10), wherein the microwave generation source (1), the waveguide component (3) and the microwave signal receiver (8) are sequentially connected through a coaxial line (2), holes are formed in two sides of a cavity of the waveguide component (3), the quartz tube (4) is inserted into the cavity of the waveguide component (3) through the holes, the vacuum electrodes (5) are respectively arranged at two ends of the quartz tube (4), a hollow cathode (6) is arranged on each vacuum electrode (5), the quartz tube (4) is connected with the vacuum pump (7), the vacuum electrodes (5) at two ends of the quartz tube (4) are respectively connected with the positive electrode and the negative electrode of the direct current power supply (10), the waveguide component (3) is integrally rectangular, inside is cut apart into two upper and lower cavitys by the metal sheet, 4 diameters are 25 mm's hole is seted up to two upper and lower cavity bilateral symmetry in waveguide subassembly (3), has all inserted quartz capsule (4) in every hole, the external diameter of quartz capsule (4) is 20mm, and the wall thickness is 2mm, and is long for 300mm, vacuum in quartz capsule (4) is 1 Torr.

2. A glow discharge plasma microwave waveguide interaction measuring apparatus as claimed in claim 1, wherein: a plurality of the quartz tubes (4) on the same side are connected in parallel.

3. A glow discharge plasma microwave waveguide interaction measuring apparatus as claimed in claim 1, wherein: the waveguide component (3) is a DC-2 GHz waveguide component.

4. A glow discharge plasma microwave waveguide interaction measuring apparatus as claimed in claim 1, wherein: the direct current power supply (10) provides adjustable voltage of 0-1500V.

5. A glow discharge plasma microwave waveguide interaction measuring apparatus as claimed in claim 1, wherein: the hollow cathode (6) is a metal molybdenum sheet, the thickness is 2mm, the diameter is 20mm, and the length is 20 mm.

6. A glow discharge plasma microwave waveguide interaction measuring apparatus as claimed in claim 1, wherein: the vacuum electrode (5) is a copper rod with the diameter of 3mm and the length of 52 mm.

7. A glow discharge plasma microwave waveguide interaction measuring apparatus as claimed in claim 1, wherein: an ammeter (11) is connected to the direct current power supply (10) in series, and a voltmeter (12) is connected to the direct current power supply (10) in parallel.

8. A glow discharge plasma microwave waveguide interaction measuring apparatus as claimed in claim 1, wherein: and a resistor (9) is connected in series between the vacuum electrode (5) and the direct current power supply (10).