| 摘要 |
A plasma processing chamber is provided which provides improved wafer area pressure control. The plasma processing chamber is a vacuum chamber with a device connected for generating and sustaining a plasma. Part of this device would be an etchant gas source and an exhaust port. A confinement ring defines an area above a wafer. The wafer area pressure is dependent on the pressure drop across the confinement ring. The confinement ring is part of a confinement device that provides wafer area pressure control greater than 40%. Such a confinement device may be a fixed vertical restriction ring in addition to the confinement ring, where the confinement ring is adjustable. In the alternative, three adjustable confinement rings may be used to provide the desired wafer area pressure control. |
