The temperature of the cathode target of the pvd coating machine has a very great influence on the arc. Whether the temperature control is timely and reasonable directly affects the coating effect of the substrate and the production efficiency. Therefore, the general manufacturers operating the vacuum coating machine generally need to have experience to understand the coating. technical professionals, which can control costs and improve efficiency. So what effect does the temperature of the cathode target of the vacuum coater have on the arc? The stability of the cathodic arc discharge combustion of the target source depends on the evaporation temperature of the cathode surface. Lowering the cathode surface temperature will bring about a high arc combustion stability. At the same time, lowering the temperature of the cathode evaporation surface will also lead to a reduction in the large particle number and large sputter in the metal vapor.

       Observe the combustion of the target cathode arc of the vacuum ion coater. Whenever the arc is extinguished, the arc spot is always found to be extremely rough. Sometimes even piled arc spots appear. After extinguishing, observe that the target surface has turned red, and the target surface temperature is very high. The appearance of the rough arc spot makes the arc current more concentrated on the target surface, which leads to the excessive concentration of the spot current on the target surface under the arc spot, which makes the target surface temperature under the arc spot higher and produces a large amount of thermionic emission. The result of a large number of thermionic emission locally on the target surface, on the one hand, neutralizes a large number of space charges, making the electric field on the cathode surface a deceleration field, and even causing the electric field on the cathode surface to be equal to zero. On the other hand, the massive thermionic emission produces a considerable cooling effect on the cathode surface. The result is neither the strong electric field generated by the space charge to sustain the surface emission, nor the extremely high surface temperature to generate thermionic emission, leading to the extinction of the arc.
      Therefore, in the design of the multi-arc target source of the pvd coating machine, attention should be paid to the sufficient cooling of the cathode target. It is best to use direct water cooling. In the case of indirect water cooling, the adjacent parts such as the cathode seat should be made of materials with good thermal conductivity (such as copper, aluminum, etc.)