The vacuum coating mainly uses glow discharge impact argon (AR) ions on the surface of the target.
The atoms of the target are ejected and stacked on the surface of the substrate to form a thin film.The properties and uniformity of sputtered films are better than those of evaporated films, but the coating speed is much slower than that of evaporated films.Almost all new sputtering equipment use powerful magnets to spiral electrons to accelerate the ionization of argon around the target,
The collision probability between the target and argon ions is increased,
Increase the sputtering rate.Generally, DC sputtering is used for metal coating, while RF AC sputtering is used for non-conductive ceramic magnetic materials. The basic principle is to use glow discharge in vacuum
When argon (AR) ions impact the surface of the target, the cations in the plasma will accelerate to rush to the negative electrode surface as the splashed material. This impact will make the material of the target fly out and deposit on the substrate to form a thin film.Generally speaking, there are several characteristics of film coating by sputtering process: (1) metal, alloy or insulator can be made into film material.(2) Under appropriate setting conditions, the film with the same composition can be made from multiple and complex targets.(3) The mixture or compound of target material and gas molecules can be made by adding oxygen or other active gases in the discharge atmosphere.(4) The target input current and sputtering time can be controlled, and it is easy to obtain high-precision film thickness.(5) Compared with other processes, it is conducive to the production of large-area uniform films.(6) The sputtered particles are hardly affected by gravity, and the positions of target and substrate can be arranged freely.(7) The adhesion strength between the substrate and the film is more than 10 times that of the general evaporated film, and because the sputtered particles have high energy, they will continue to diffuse on the film-forming surface to obtain a hard and dense film. At the same time, this high energy enables the substrate to obtain a crystalline film at a lower temperature.(8) At the initial stage of film formation, the nucleation density is high, and very thin continuous films below 10 nm can be produced.(9) The target has long service life and can be produced automatically and continuously for a long time.(10) The target can be made into various shapes, which can cooperate with the special design of the machine for better control and the most efficient production.
Post time: Oct-12-2021