The working principle of magnetron sputtering is that electrons collide with argon atoms in the process of flying to the substrate under the action of electric field E, which ionizes them to produce Ar positive ions and new electrons; The new electrons fly to the substrate, and Ar ions accelerate to the cathode target under the action of electric field, and bombard the target surface with high energy, causing the target to sputter. In sputtered particles, neutral target atoms or molecules are deposited on the substrate to form a thin film, and the generated secondary electrons will be subjected to the action of electric field and magnetic field, resulting in the direction drift indicated by e (electric field )× b (magnetic field), which is referred to as E×B drift for short, and its trajectory is similar to a cycloid. If it is an annular magnetic field, the electrons move around the target surface in the form of approximate cycloid, and their movement path is not only very long, but also bound in the plasma region near the target surface, and a large amount of Ar is ionized in this region to bombard the target, thus achieving a high deposition rate. With the increase of the number of collisions, the energy of secondary electrons is exhausted, gradually away from the target surface, and finally deposited on the substrate under the action of electric field E. Because the energy of this electron is very low, the energy transferred to the substrate is very small, resulting in a low temperature rise of the substrate. Magnetron sputtering is a collision process between incident particles and targets. Incident particles undergo a complex scattering process in the target, and collide with the target atom, transferring part of momentum to the target atom, which collides with other target atoms to form a cascade process. In this cascade process, the target atoms near some surfaces gain enough momentum to move outward, and are sputtered off the target.