The Hollow Cathode Plasma Electron Gun

Millimeter wave, terahertz band is the important direction of development of the power vacuum microwave devices. As the device is small, once the frequencies is above 100 GHz, high density and thin electron beam is required to achieve sufficient output power, so the demands of cathode is more, generally it is difficult to achieve for the traditional hot cathode. View from the current study, plasma electron gun can produce high density current to reach the demands mentioned above. Plasma cathode electron gun use a low pressure inert gas discharge to produced plasma as the electron source, the electron will be extracted by the anode from the plasma boundary and then accelerated to from electron beam, the gun have many advantages, such as: no need filament heating, long life, simple structure, easy control, plasma produced indirectly beating the Cathode and so on.In this paper, plasma electron gun has been studied, mainly the following aspects:1. Given domestic and foreign literature, outlining the characteristics of the plasma electron gun and the domestic and international overview of current research, the purpose of this research, background and significance are detailed described.2. Describe the basic process of gas discharge, the basic nature and characteristics of discharged plasma gas, glow discharge characteristics and some parameters of the calculation.3. Introduce the basic theory of the hollow cathode discharge, the calculation method of hollow cathode current is given, using gas-discharge numerical simulation software OOPIC simulate the discharge process of a hollow cathode ,the impact of different structures and different gas pressure of a hollow cathode on the discharge process is analysised. All the work provides the theoretical basis for the design and experiment of the hollow plasma electron gun.4 Complete dynamic vacuum experimental system, the system carried out in accordance with principles of the design of hollow cathode discharge plasma gun experiments, hollow cathode discharge was achieved, and to analyze beam current and discharge voltage, gas pressure relationship. And make further improvements, after joining the grid of electron gun have been investigated. For the plasma provide the basis for the design of electron gun.