PLANETARY MAGNETRON

摘要

A small unbalanced magnet assembly (60) is scanned in a preferably retrograde planetary or epicyclic path (92) about the back of a target (90) being plasma sputtered including an orbital rotation about the center axis (72) 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 (74), a fixed center gear (62), and an idler gear (76) and a follower gear (74) rotatably supported in the drive plate supporting a cantilevered magnet assembly (84) on the side of the drive plate facing the target. A belt (342) and pulleys (344, 346) may be substituted for the gears. 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 (302, 304, 306) may be added or non-circular gears (310) be used. Auxiliary electromagnetic coils (254, 258) positioned beside the chamber and below the pedestal (122) may create a focusing magnetic field.