SiO₂誘電体ターゲットの高周波マグネトロンスパッタリングにおける2重円環状侵食パターンの形成および均一性の検討

抄録

A circular erosion pattern is formed on the surface of a circular metal conductor target with permanent magnets on its back in rf magnetron sputtering. In this case, the theory behind the erosion pattern has been established. On the other hand, in the case of a dielectric target, a double circular erosion pattern is formed. This pattern is widely known qualitatively and experimentally; however, it has not yet been studied theoretically. In this study, we performed a magnetron sputtering experiment with a SiO₂ dielectric target, and were able to confirm the formation of a double circular erosion pattern, which agrees with qualitative theory. Moreover, insulation resistance varied with the thickness of the SiO₂ target; thus the dimensions of the double circular erosion pattern varied. Furthermore, we confirmed that a double circular erosion pattern changed by making a gap between the SiO₂ target and guard ring. We discussed about utilization rate of the target.