Principle of DC Magnetron Sputtering Power Supply
The DC magnetron sputtering power supply is a kind of physical vapor deposition. Metals, semiconductors, insulators and other materials are usually manufactured by general sputtering methods, which are characterized by relatively simple equipment, not difficult to control, large plating area, and strong adhesion. The DC magnetron sputtering power supply realizes high speed, low temperature and low damage. Since high-speed sputtering is performed under low pressure, the dissociation rate of the gas must be effectively increased. Magnetron sputtering introduces a magnetic field to the surface of the target cathode and uses the magnetic field to confine the charged particles to increase the plasma density and thereby increase the sputtering rate. Then, let's understand the principle of the DC magnetron sputtering power supply!
Principles and characteristics of DC magnetron sputtering power supply technology
Because the development of DC magnetron sputtering power supply technology solves the defects of cathode sputtering, it effectively overcomes the weak points of low cathode sputtering speed and the temperature of circuit board being raised by electrons, so it has been rapidly developed and widely used.
The principle of DC magnetron sputtering power supply is that in magnetron sputtering, electrons moving in a magnetic field are subjected to Lorentz force, so their trajectories produce bending and spiral motions, and their motion paths become longer, so they interact with the working gas molecules. The number of collisions increases, the plasma density increases, and the magnetron sputtering speed is very high. On the other hand, because the energy of the atoms incident on the substrate surface is also increased, the quality of the film can be greatly changed. At the same time, when the electrons that have lost energy due to multiple collisions reach the anode, they have become low-energy electrons and will not overheat the substrate. Therefore, the advantages of magnetron sputtering are "high speed" and "low temperature". The characteristic of this method is that it cannot produce an insulator film. In addition, the uneven magnetic field used for the magnetron electrode will cause obvious uneven marking of the target material, and the utilization rate of the target material is low, usually only 20%-30%.
The principle of the DC magnetron sputtering power supply is that the plasma generated by the rare gas due to abnormal glow discharge uses the electric field effect to bombard the outer surface of the cathode target, and sputter the molecules, atoms, ions and electrons on the outer surface of the target. The particles must have kinetic energy and must be directed towards the outer surface of the matrix,
The beginning of the DC magnetron sputtering power supply is simple DC bipolar sputtering. Its advantage is that the equipment is simple, but the deposition speed of DC bipolar sputtering is low; in order to maintain self-inhibited discharge, it cannot be carried out under low pressure; it cannot be sputtered. Defects such as radiation insulation materials limit its use. After adding a hot cathode and auxiliary anode to the DC bipolar sputtering device, DC tripolar sputtering will be constructed. The thermionics generated by the added hot cathode and auxiliary anode enhance the ionization of sputtering gas atoms, so that sputtering can be carried out under low pressure; in addition, the sputtering voltage can also be reduced, and the sputtering voltage can be carried out under low pressure and low voltage. Sputtering; The discharge current also becomes larger, and it can be operated independently without being affected by the voltage. An electrode (grid mesh) is added before the hot cathode to form a quadrupole sputtering device, which can stabilize the discharge. However, these equipments are difficult to obtain high-concentration plasma regions, and the deposition rate is low, so they have not been widely used in industry.
The above is the principle of DC magnetron sputtering power supply, if you need to know more, please feel free to contact us!