The structure of the planar magnetron sputtering target of the coating equipment, in the actual case, the initial velocity of the electron is not zero, and the electrons do not run linearly along the electric field toward the anode, but rather do cycloid motion under the effect of orthogonal electromagnetic fields. That is greatly increased the probability of collision with gas molecules, and improved the ionization rate of argon gas. A larger number of argon ions are produced to bombard the target, increasing the sputtering rate. The sputtering rate is about 10 times higher than that of the DC two poles sputtering. For many targets, the sputtering rate has reached the evaporation rate of the electron beam, which is a great progress in the cathode sputtering technology. It can shorten deposition time and improve production efficiency.
The magnetic field component of the parallel target surface is not uniform. In the place where the magnetic field is the strongest, the parallel target surface of the magnetic field is the largest, and the electromagnetic fields have the greatest constraining force on electrons. Therefore the electron density in this range is the largest, and the probability of collision ionization with argon is the largest. The intensity of the glow is the largest, and there is the highest glow intensity with a very strong glow (rectangular or circular) ring on the target surface. The largest amount of argon ion is produced in this region, and the more intense the cathode sputtering is to the target. The target material in this area is etched quickly, and the target material is not evenly consumed and depressions appear. The magnetic flux directly passes through the target surface, and the magnetic flux generated on the target surface determines the degree of “magnetism”. After multiple sputtering, the target material becomes thinner, the magnetic flux increases, and the sputtering is easier.
This positive feedback process reduces the utilization of the target. For the valuable target, the low utilization rate of the planar magnetron sputtering target is the deficiency of the planar magnetron sputtering target.