| 摘要 |
A focus ring for a plasma processing apparatus has an inner region, middle region, and outer region, disposed in this order from the inner side to surround a target substrate. On the side to be exposed to plasma, the surfaces of the inner region and outer region consist essentially of a dielectric, while the surface of the middle region consists essentially of a conductor. The middle region is arranged to shift the peak of plasma density to the outside of the peripheral edge of the target substrate. If there is no middle region, the peak of plasma density appears substantially directly above the peripheral edge of the target substrate. |
