Multi-segment plasma confinement ring structure

A confinement ring for use in a plasma processing chamber includes an upper horizontal section, an upper vertical section, an intermediate section, a lower vertical section, a lower horizontal section, and a vertical extension. The upper horizontal section extends between an inner upper radius and a first outer radius of the restraint ring. The intermediate section extends between an inner upper radius and a second outer radius of the restraint ring. The lower horizontal section extends between an inner lower radius and a second outer radius, and a vertical extension extends downwardly from the lower horizontal section near the inner lower radius. The upper vertical section extends between the upper horizontal section and the intermediate section near the inner upper radius, and the lower vertical section extends between the intermediate section and the lower horizontal section near the second outer radius. 一种在等离子体处理室中使用的约束环包括上水平段、上竖直段、中间段、下竖直段、下水平段以及竖直延伸部。该上水平段在约束环的内上半径与第一外半径之间延伸。该中间段在约束环的内上半径与第二外半径之间延伸。该下水平