The Integrated Design Of The Linear Ion Source And Its Performance Research

In recent years, people apply the plasma acceleration technology of the aerospace thruster to the technology of film depositing, and develop kinds of ion sources to realize the technology of the ion beam assisted deposition, preplating and direct deposition. Thereinto, the linear ion source is getting the emphasis of the future research work with its advantages of high beam current density, broad energy range, simple structure, low cost and reliable performance, and is applied extensively in the coating process. Now the research and development of the linear ion source in China is still in backward level. Comparison with abroad, it still has a certain disparity in the use characteristics and so on. Most of them depend on the imitation and experiment without an integrated guidance and method for designing and use. For this reason, based on the principle of the ion source, we carry on the comprehensive study to the structural design and discharge performance of the linear ion source by the computer simulation method.On the basis of the design method and procedure, this article mainly includes the following research contents:(1) Investigate and summarize the origin of the linear ion source, the development situation and research trend of the linear ion source home and abroad.(2) Introduce the principle, features and applications of the linear ion source. Preliminary design its structure based on its principle, mainly including the design of the integral structure, electric field, magnetic field, water cooling system and gas distribution system.(3) Using the Finite Element Method, we carry on the simulation to the whole electromagnetic field of the linear ion source by the software of ANSYS. Change the dimension of the permanent magnet, field yoke and pole terminal to find the relation between the magnetic field and its structure; change the distance between the anode and cathode to find the affecting factors of the electric field. Based on the simulation results, we conduct its preliminary optimization according to the requirement of the electric field and magnetic field. (4) Based on the method of the PIC-MCC, conduct the simulation for the discharge process of the ion source, find the relation between the beam performance and the influencing parameter of the working volt, operating pressure, type of gas and substrate bias. We get the following conclusion:with the increase of the working volt, both the density and the average energy are increased; with the increase of the operating pressure, the density of the beam is increased while its average energy is decreased; with the increase of the substrate bias, both the density and the average energy are increased. The beam properties also are related with its type of gas.(5) Using the linear ion source built in FMA 90/80 multiple arc ion plating equipment, we carry on the actual measurement of the magnetic field and the performance experiments of the linear ion source. By comparing the measuring result with its simulated result of the magnetic field, validate the correctness of the simulation. By changing the working volt, operating pressure and substrate bias in the experiments, we get the coincident results with above simulated result for the discharge process.