Research Of Discharge Mechanism In Cathodic Arc Evaporation Source

The vacuum coating technology is a physical method and in the process there is no electroplating wastewater. It is a clean production and it has a broad application prospects. The cathodic arc evaporation plating belongs to the vacuum coating technology but more advanced. It was developed to be a physical vapor deposition technology in the seventh decade of twenty century, and it has been the head of ion plating technology because of the high ionization rate, well diffraction, high coating quality, strong adhesion and so on. The cathodic arc ion plating technology is used widely to tools, molds, hardware and accessories such as plating wear-resistant, heat-resistant and corrosion-resistant film industry.To research the discharge mechanism of cathodic arc evaporation plating, we should analysis the plasma during the DC discharging firstly, especially the plasma nearby the target surface. But the breakdown time of DC discharge is very shot. For the plasma, the electronic energy exist less than1nanoseconds, electron conveying for nanoseconds, ion transport as microseconds and so on. These problems make the plasma research and simulation more complicated.This paper is based on the design application of multi-arc ion plating device which is from SKY. To use the multi physics coupling software COMSOL Multiphysics to simulate. During the plasma simulation, to use the DC Discharge Module of Plasma Module and Electrical Circuit Module of AC/DC Module and obtain the plasma parameters and discharge parameters accord to the practice. About the magnet simulation, to use the Magnetic Fields, No Currents Module of AC/DC Module and we find to use magnetic ring is more energy saving if possible. What is more, chose the Particle Tracing Module to simulate the trajectory of Arτ when magnetic field is a uniform. Then compare the result of Larmor radius and find the error between the simulation and the theoretical value is less than0.1%. Finally, analysis effects of additional magnetic field on the spot motion during the DC discharge. It shows that the spot motion has not been better when the magnetic field of target surface stronger. Because of other completed theories, the operator should adjust the magnetic field component position according to the experimental observation so that the target surface magnetic field is moderate, and then reduce the droplet reflection from the spot. At the same time, the spot could get the target systolic motion for the uniform etching.Aiming at studying the process of DC discharge and the additional magnetic field, magnetic filtration multi-arc ion plating system is used for experiment. Via changing the distance between the magnetic component and the cathode surface to adjust the magnetic flux density. Get the pictures of cathode spot motion in different magnetic flux density. Through the analysis of the experimental results, find the cyclotron force leads to rotation movement, arc-stable force controls the charges in a determine position, radial thrust controls the movement on the target surface for the etching uniformity; Axially symmetric magnetic field combines transverse magnetic field with an acute angle principle advantages and promotes arc spot splitting, reduces droplet emission so that to improve the quality of the thin film. But the strong magnetic field working for a long time will cause the target etching worse and reduce the utilization rate of the target material. In order to improve the target erosion, to observe the spot motion on target surface and to regulate the magnetic flux density timely are necessary.