Principle of vacuum coating equipment

      Principle of vacuum coating equipment

Electronic under the action of electric field, accelerate the process of flying to the substrate with argon atom collision, ionization out large amounts of argon ions and electrons, electronic fly to the substrate. Accelerated in the electric field under the influence of argon ion bombardment of target materials, sputtering out a large number of target material atoms, the target of neutral atoms (or molecules) is deposited on the substrate into film. Secondary electron in accelerating the process of flying to the substrate by magnetic lorentz magnetic force, the influence of bound in * plasma on the surface of the target area, the area of plasma density is high, secondary electron under the action of magnetic field around the target surface as a circular motion, the electron motion path is very long, constantly in the process of movement and argon atom collision ionization out large amounts of argon ion bombardment of target, electronic energy reduce gradually, after many collision cast off the yoke of the magnetic field lines, away from the target material, the final deposition on the substrate.
Magnetron sputtering is with magnetic field and to extend the electronic motion path, change the movement direction of the electron, improve the working gas ionization rate and the effective utilization of the energy of an electron.
Electronic home is more than substrate, vacuum chamber wall and target source anode and electronic home. But usually substrate with the vacuum chamber and the anode in the same electric potential. The interaction of the magnetic field and electric field (E X B shift) to assume a single electron trajectory three-dimensional spiral, rather than merely to circular motion on the target surface. As for the target surface sputtering outline of the circle type, that is the target source magnetic field lines in circular shape shape. The lines of magnetic force distribution in a different direction to film has a lot to do.
Work under E X B shift mechanism not only of magnetron sputtering, arc plating target source, ion source, plasma source in time under the principle of work. The difference is the electric field direction and size of the voltage and current.