Completely flat erosion magnetron sputtering using a rotating asymmetrical yoke magnet

A completely flat erosion magnetron 5-inch cathode has been developed for planer magnetron sputtering using a rotating asymmetrical yoke magnet. The yoke magnet was composed of an iron yoke base with a 70 mm diameter, an annular outer yoke, a center Fe-Nd-B magnet which was shifted from the yoke base center, and an assisted Fe-Nd-B magnet which was attached to a part of the outer yoke. In order to optimize the magnetic flux density for uniform target erosion from center to outer area, several diameters of the center Fe-Nd-B magnet, from 25 to 36 mm, were tested by the first experiment, and secondly the outer yoke structure was optimized using the first experimental results. The obtained final target utilization was 77% and erosion depth uniformity for the 4-inch diameter was ±6%.