Study On Enhanced Pulsed Ion Source

Diamon-like carbon film is widely used because of many advantages, such as high hardness, excellent wearability, chemical stability and good infared property. Pulsed arc ion deposition is an effective method to prepare DLC films, it has many attractive advantages, such as high ionization, high ion energy,high deposition ratio, high utilization of cathode material, and with simple evaporative source.In addition, it is easy to operate, no pots needed, and common low voltage power is satisfied, all these advantages are suitable for production of the diamond-like carbon films and alloy films.Meantime, since the pulsed discharging is used, it overcomes the droplet produced during the continuous arc ion deposition. And no minus bias needed for the substrate, therefore, avoids minus bias discharging. Because of these fine characters, experts at home and abroad working in this field pay great attentions to it. Although this method can decrease microparticls in some degree, there still have many graphite microparticls on the surface of the DLC films, the size of the graphite microparticls is big from several hundreds nm to um.These microparticls have great effect on the properties of the DLC films and restricte the use of this films.In order to eliminate the microparticls on the surface, improve properties of DLC films, it is necessary to research a new kind plused ion source. In this paper, the principle and design process of enhanced pulsed ion source is introduced. Enhanced pulsed ion source mainly includes two parts: pulsed ion source and magnetic filter. In this paper, the design of magnetic filter, calculation of magnetic field and power supply for magnetic filter is illustrated. Parts of character is studied, magnetic field is measured and simulated.Experiment of preparing DLC films with enhanced pulsed ion source is researched also. Compared with pulsed arc ion source, the experiment result shows that, the size and number of microparticles is reduced greatly, the surface of films is smooth. The average roughness Ra decreases from 80 nanometers to 1.178 nanometers. When the current of magnetic coil increases from 0 Ampere to 4 Ampere, the average roughness Ra is reduced from 4.504 nanometers to 1.178 nanometers. In this paper, the reason that microparticles are filted by magnetic filter is discussed in detail. According Raman spectra analysis, sp~2 bond and sp~3 bond exit in the DLC filmswhich are prepared with the enhanced pulsed ion source. Area ratio of D peak and G...