Magnetron sputtering is a technique that utilizes accelerating ions in a vacuum chamber and allowing them to collide with a target material to produce a coating. By applying a constant magnetic field and using a magnetron or grid, ions can be focused into a very small area, and the ion trajectory can be adjusted to achieve the desired coating effect.



The working principle of magnetron sputtering mainly involves the behavior of electrons in electric and magnetic fields, as well as the sputtering process of the target material. Specifically, its working principle is as follows:

Electronic behavior: Under the action of electric field E, electrons collide with argon atoms during their flight towards the substrate, ionizing and producing Ar cations and new electrons. The new electrons continue to fly towards the substrate, while Ar ions accelerate towards the cathode target under the action of the electric field.
Target sputtering: High energy Ar ions bombard the surface of the target, causing sputtering of the target material. Neutral target atoms or molecules in the sputtered particles deposit on the substrate to form a thin film.

Drift of secondary electrons: The secondary electrons generated during the sputtering process are subjected to the effects of electric and magnetic fields, resulting in directional drift in the direction of E (electric field) × B (magnetic field), abbreviated as E × B drift. Its motion trajectory approximates a cycloid. In a circular magnetic field, electrons move in a circular motion on the target surface in an approximate cycloid form, confined in the plasma region near the target surface, and ionize a large amount of Ar in this region to bombard the target material, thereby achieving a high deposition rate.

Energy consumption and deposition: As the number of collisions increases, the energy of secondary electrons gradually depletes, eventually moving away from the target surface and depositing on the substrate under the action of electric field E. Due to the low energy of these electrons, the energy transferred to the substrate is very small, resulting in a lower temperature rise of the substrate.



Advantages of Magnetron Sputtering Coating

Magnetron sputtering coating technology, as an advanced surface coating technology, has several significant advantages:

Low temperature performance of substrate: Compared to other coating techniques such as secondary sputtering and thermal evaporation, magnetron sputtering has less heating, which is beneficial for protecting the thermal sensitivity of the substrate.

High deposition rate: Due to the effective binding and ionization of secondary electrons in the plasma region near the target surface, a large number of Ar ions are bombarded onto the target material, and magnetron sputtering achieves a high deposition rate.

Environmental protection technology: The magnetron sputtering coating process is carried out in a vacuum environment, which does not produce harmful gas emissions and does not pollute the environment.
Coating firmness: The mechanical strength between the sputtered film and the substrate is improved, the adhesion is enhanced, and the coating has good firmness.

Easy to operate and control: During the coating process, as long as the sputtering conditions such as pressure and electrical power are stable, a relatively stable deposition rate can be obtained, and the operation is relatively easy to control.



Uniform film formation: Magnetron sputtering technology can achieve high uniformity and high-quality thin film coatings, resulting in a general increase in film density.

Good performance: Sputtered metal films typically exhibit excellent optical, electrical, and certain special properties, meeting various application requirements.

Continuous work and automation: The magnetron sputtering coating process can work continuously and is easy to achieve automatic control, making it suitable for industrial assembly line operations.

In summary, magnetron sputtering coating technology has been widely applied in multiple fields due to its unique advantages, and continues to develop and improve with the advancement of technology.