摘要 |
A small unbalanced magnet assembly is scanned in a retrograde planetary or epicyclic path about the back of a target being plasma sputtered including an orbital rotation about the center axis of the target and a planetary rotation about another axis rotating about the target center axis. The magnet assembly may pass through the target center, thus allowing full target coverage. A geared planetary mechanism may include a rotating drive plate, a fixed center gear, and an idler and a follower gear rotatably supported in the drive plate supporting a cantilevered magnet assembly on the side of the drive plate facing the target. The erosion profile may be controlled by varying the rotation rate through the rotation cycle or by modulating the target power. A second planetary stage may be added or non-circular gears be used. Auxiliary electromagnetic coils may create a focusing magnetic field. |