Electron beam heating principle and characteristics of PVD coating machine: The electron beam heating evaporation source of PVD coating machine uses the hot cathode to emit electrons under the action of an electric field to become a high energy density electron beam, which directly bombards the coating material. The kinetic energy of the electron beam is converted into heat energy, so that the material is heated and gasified to complete the evaporation coating.

       The advantages of electron beam heating and evaporation of PVD coating machine:
       ①The electron beam heating of the coating machine has a higher energy density than the resistance heating, and can evaporate high melting point materials, such as W, Mo, Al2O3, etc., and can obtain a higher evaporation rate;
       ②The evaporated material is placed in a water-cooled copper crucible, which can avoid the contamination of the crucible material and prepare high-purity thin films;
       ③The kinetic energy of the electron beam evaporation particles is large, which is beneficial to obtain a dense and good bonding film.
       Disadvantages of electron beam heating of PVD coating machine:
       ①The structure is more complicated and the equipment price is more expensive;
       ② If the vapor density near the evaporation source of the PVD coating machine is high, there will be interaction between the electron beam and the vapor particles in the PVD coating machine, and the energy of the electrons will be dissipated and the orbit will be shifted. At the same time, it causes the excitation and ionization of vapor and residual gas, which will affect the quality of the film.