Working principle of electron beam evaporation coating equipment (principle and working flow of evap

Electron beam evaporator is a physical vapor deposition (PVD) technology based on electron beam evaporation. It uses electron beam to directly heat evaporated materials (usually particles) under vacuum, and transports the evaporated materials to the substrate to form a thin film. Electron beam evaporation can deposit thin films with high purity and precision.Electron beam evaporation coating machine, as a process experimental instrument, is usually used in the field of material science. It is a universal coating machine, which is used to coat various single-layer films and multilayer films. Can be plated with various hard films and metal films. It is mainly used for preparing metal electrodes of nano-devices and organic photoelectric devices, and preparing catalyst film layers for growing nano-materials.

Application scope of electron beam evaporation coating machineElectron beam evaporation coating machine is widely used in various applications because of its high stacking rate and high material power. For example, high-performance aerospace and automobile industries have high requirements for high temperature resistance and wear resistance of materials; Hard coating of durable things; And chemical barriers and coatings to protect the appearance in corrosive environment. Electron beam evaporation is also used in optical films, including laser optics, solar panels, glass and architectural glass, to endow them with the required conductivity, reflection and transmission characteristics.Advantages and disadvantages of electron beam evaporation coating machineElectron beam evaporation technology can evaporate high melting point materials, with higher power than general resistance heating evaporation technology. Electron beam evaporation coating machine can be widely used for optical coating of high purity film and conductive glass. It also has the potential industrial applications of wear-resistant and thermal barrier coatings for aerospace industry, cutting and hard coatings for east and west industries. However, the electron beam evaporation coating machine can not be used to coat the inner and outer surfaces with a few messy shapes. In addition, filament degradation in electron gun may lead to uneven evaporation rate.Work flow of electron beam evaporation coating machineElectron beam evaporation coating machine is based on the evaporation of tungsten wire. A current of about 5 to 10 kV passes through the tungsten wire (located outside the stacking area to prevent pollution) and heats it to the point where electron thermionic emission occurs. Use a permanent magnet or electromagnet to focus electrons and guide them to the evaporation material (placed in the crucible). In the process of electron beam impacting the surface of evaporation pill, its kinetic energy is converted into heat, which releases high energy (more than several million watts per square inch). Therefore, it is necessary to water cool the hearth containing evaporation materials to prevent melting.Difference between Electron Beam Evaporation Coating Machine and Thermal Evaporation Coating MachineThe difference between the electron beam evaporation coating machine and the thermal evaporation coating machine is that the electron beam evaporation coating machine bombards the object with a beam of electrons, generating high energy for evaporation, and the thermal evaporation finishes the process by heating. Compared with the thermal evaporation coating machine, the electron beam evaporation coating machine provides high energy; However, it will be difficult to control the thickness of the film in the order of 5nm. In this case, a good thermal evaporator with thickness monitor will be more suitable.Advantages of electron beam evaporation coating machine compared with thermal evaporation coating machineElectron beam evaporation coating machine can heat materials to a higher temperature than thermal evaporation coating machine. This allows a very high stacking rate and evaporation of high-temperature materials and refractory metals such as tungsten, tantalum or graphite.Electron beam evaporation coating machine can deposit thinner and higher purity films. The water cooling of the crucible strictly restricts the electron beam heating to the area occupied only by the source material, thus eliminating any unnecessary pollution of adjacent components.The evaporation source of electron beam evaporation coating machine has various sizes and configurations, including single cavity or multi-cavity.