Wafer edge protection and efficiency using inert gas and ring

Embodiments of the invention generally relate to an apparatus and method for plasma etching. In one embodiment, the apparatus includes a process ring with an annular step away from an inner wall of the ring and is disposed on a substrate support in a plasma process chamber. A gap is formed between the process ring and a substrate placed on the substrate support. The annular step has an inside surface having a height ranging from about 3 mm to about 6 mm. During operation, an edge-exclusion gas is introduced to flow through the gap and along the inside surface, so the plasma is blocked from entering the space near the edge of the substrate.