Characteristics of magnetron sputtering coating
(3) Low energy sputtering. Due to the low cathode voltage applied to the target, the plasma is bound by the magnetic field in the space near the cathode, thus inhibiting the high-energy charged particles to the side of the substrate people shot. Therefore, the degree of damage to the substrate such as semiconductor devices caused by charged particle bombardment is lower than that caused by other sputtering methods.
(4) Low substrate temperature. Magnetron sputtering sputtering rate is high, because the cathode target in the magnetic field within the region, that is, the target discharge runway within a small localized area of the electron concentration is high, while in the magnetic effect outside the region, especially away from the magnetic field of the substrate surface nearby, the electron concentration due to the dispersion of the much lower, and may even be lower than the dipole sputtering (because of the difference between the two working gas pressure of an order of magnitude). Therefore, under magnetron sputtering conditions, the concentration of electrons bombarding the surface of the substrate is much lower than that in ordinary diode sputtering, and an excessive increase in substrate temperature is avoided due to the reduction in the number of electrons incident on the substrate. In addition, in the magnetron sputtering method, the anode of the magnetron sputtering device can be located around the cathode vicinity, and the substrate holder can also be ungrounded and in suspension potential, so that the electrons may not pass through the grounded substrate holder and flow away through the anode, thereby making the high-energy electrons bombarding the plated substrate reduced, reducing the increase in substrate heat caused by the electrons, and greatly attenuating the secondary electron bombardment of the substrate resulting in the heat generation.
(5) Uneven etching of the target. In the traditional magnetron sputtering target, the use of an uneven magnetic field, so the plasma will produce a local convergence effect, will make the target on the local position of the sputtering etching rate is great, the result is that the target will produce a significant uneven etching. The utilization rate of the target is generally about 30%. In order to improve the utilization rate of the target material, you can take a variety of improvement measures, such as improving the shape and distribution of the target magnetic field, so that the magnet in the target cathode internal movement and so on.
Difficulty in sputtering magnetic material targets. If the sputtering target is made of a material with high magnetic permeability, the magnetic lines of force will pass directly through the interior of the target to occur a magnetic short-circuit phenomenon, thus making magnetron discharge difficult. In order to generate the space magnetic field, people have carried out a variety of studies, for example, to saturate the magnetic field inside the target material, leaving many gaps in the target to promote the generation of more leakage of magnetic target temperature increases, or to reduce the magnetic permeability of the target material.
–This article is released by vacuum coating machine manufacturer Guangdong Zhenhua
Post time: Dec-01-2023