The cause of uneven film by vacuum magnetron sputtering coating machine
What are the factors that lead to uneven magnetron sputtering vacuum coating machine? The friend that major is engaged in the job of this respect actually still comparative understanding, it basically can be divided into the following a few factors are: vacuum condition, magnetic field, argon.
The operation of magnetron sputtering vacuum coating machine is that the argon ions formed by electron bombardment of argon are bombarded by the orthogonal magnetic field under the vacuum state, and the target ions are deposited on the surface of the workpiece to form a film.
In the vacuum state, the pumping system is required for control. Each pumping port should be started simultaneously and with the same strength, so that the uniformity of the pumping can be well controlled. If the pumping is not uniform, the pressure in the vacuum chamber cannot be uniform, and the pressure has a certain influence on the movement of ions. In addition, the pumping time should be controlled, too short will cause a lack of vacuum, but too long and a waste of resources, but there is a vacuum gauge, it is not a problem to control.
Orthogonal field works, but you must will do one hundred percent homogeneous magnetic field intensity is impossible, generally strong magnetic field, film thickness is big, the opposite is small, so will cause the film thickness is not consistent, but in the process of production, due to the magnetic field caused by uneven uneven film are not common, why?
The original magnetic field strength is not good, but at the same time, the workpiece is in operation at the same time, and is a target atom sedimentary end of the case for many times coating process, parts for a period of time though thick and thin parts, but another time, under the action of strong magnetic field on the thin parts of the original sedimentary thickness, on the thickness of the part of the thin, so many times, after the final film, the film uniformity is good.
The uniformity of argon will also affect the uniformity of the film, the principle of which is almost the same as the vacuum degree. Because of the entry of argon, the pressure in the vacuum chamber will change, and the uniformity of the pressure can be controlled into the uniformity of the film thickness of the magnetron sputtering vacuum coating machine.