Research On The Auxiliary Anode In The Process Of Plasma Enhanced Sputtering Technology

With the development of magnetron sputtering technology, optimizing and improving traditional magnetron sputtering coating equipments have become more and more important. Domestic improving methods are centered on changing the magnetic field distribution by adding permanent magnets or magnetic coils at magnetron sputtering target and substrate, or subjoining enhanced devices such as ion source and so on. In this paper, a new-style optimum proposal from a new perspective is put forward, which is subjoining a auxiliary anode in the discharge space to change the discharge space electric field distribution and improve the plasma performance.Firstly, based on the analysis of the principle, the auxiliary anode physical structure, combining with comparing the similarities and differences between the target and the auxiliary anode, has been designed. Then this device has been produced by Chinese Academy of Sciences Shenyang Scientific Instrument Research Center. In order to research the performance of the auxiliary anode, series of experiments, with the auxiliary anode installed to the traditional magnetron sputtering coating machine, are conducted. During the experiments, the output current and voltage of the target and auxiliary anode are recorded. At the same time, the discharge glow is also taken to research the plasma distribution affected by auxiliary anode.The simulated plasma is calculated with the software of COMSOL Multiphysics. During the simulation, the plasma distribution in traditional glow discharge process without auxiliary anode is calculated. Some theoretical validation for the correctness of the model are also conducted to make sure that all the model parameter settings are correct. Basing on the model mentioned above, a modified simulation model with auxiliary anode and same parameter settings as experiment is built to simulate the glow discharge process with the auxiliary anode. All the experimental results show that the model with auxiliary anode is valid and practical. Then the model is used to research the auxiliary anode performance in glow discharge. The simulation results show that the auxiliary, with a position between the target and the substrate, can increase the ionization proportion obviously. The optimal result can obtained when the distance between the target and auxiliary anode is125mm. Serious of theoretical analysis is given here to t explain simulation results. The paper also points out the factor which should be considered in the optimization of simulation model. The optimization parameters include the distance between the center of the target and auxiliary, the auxiliary anode voltage and the height of auxiliary anode. The auxiliary anode optimum parameters are ascertained by a serious of simulation. Finally, the optimum parameters are the distance between the center of the target and the auxiliary anode is350mm, the auxiliary anode voltage is30V and the height of auxiliary anode is60mm. In the optimum condition, the electron density can reach1.11174×1017per cubic meter, which means the auxiliary anode can really increase the ionization proportion to improve the magnetron sputtering coating process.