Patent ID: 9190302
Filing Date: 2015-11-17
Classification: H01J,H01L

Abstract:
1. A plasma processing chamber for controlling plasma, comprising: a powered electrode configured to receive a substrate, the powered electrode having a first diameter and first area; a first grounded electrode having a second diameter and second area, the second diameter and second area are greater than the first diameter and first area, a first process region defined between the powered electrode and the first grounded electrode; a second grounded electrode configured as a first ring that surrounds the first grounded electrode; a third grounded electrode configured as a second ring that surrounds the powered electrode, a second process region defined between the second grounded electrode and the third grounded electrode, the third grounded electrode not being disposed over the powered electrode; a plurality of stacked confinement rings disposed between the second grounded electrode and the third grounded electrode proximate to an outer radius of the second grounded electrode and the third grounded electrode so as to maintain the second process region between the second and third grounded electrodes, such that a processing volume of the plasma processing chamber is defined by both the first and second processing regions; a first coupling to ground circuit being electrically coupled to the second grounded electrode; a second coupling to ground circuit being electrically coupled to the first grounded electrode; and a direct ground circuit being electrically coupled to the third grounded electrode; wherein each of the first and second coupling to ground circuits is defined by a variable capacitor and a single RF power supply is coupled to the powered electrode.