Tunable plasma exclusion zone in semiconductor fabrication

A plasma processing apparatus, comprising:

• a stage to support a semiconductor wafer within a chamber between a first plasma electrode and a second plasma electrode, the chamber configured to receive a process gas that reacts with an electric field generated between the first plasma electrode and the second plasma electrode to create a plasma;
• a voltage potential unit to supply a voltage potential;
• and
• a plasma exclusion zone (PEZ) ring configured to be removably affixed in the chamber a distance from an edge region of the semiconductor wafer, the PEZ ring comprising:
• a dielectric ring configured to interact with the electric field and direct the plasma with respect to the edge region of the semiconductor wafer, wherein the first plasma electrode surrounds three sides of the dielectric ring such that a sidewall of the dielectric ring at an outer circumference of the dielectric ring faces a sidewall of the first plasma electrode;
• and
• an electrode ring, fastened to the dielectric ring, electrically couplable to the voltage potential unit to receive the voltage potential and direct the plasma with respect to the edge region of the semiconductor wafer.

A plasma processing apparatus, comprising:

• a first plasma electrode;
• a second plasma electrode;
• a radio frequency power source configured to provide an electric field between the first plasma electrode and the second plasma electrode to generate a plasma;
• and
• a first plasma exclusion zone (PEZ) ring configured to interact with the electric field to cause the plasma to be at least partially excluded from an edge region of a semiconductor wafer when the semiconductor wafer is disposed between the first plasma electrode and the second plasma electrode, wherein the first PEZ ring comprises:
• a first electrode ring having a first cross-sectional profile;
• and
• a second electrode ring spaced apart from the first electrode ring by a portion of a dielectric ring, wherein:
• the second electrode ring has a second cross-sectional profile, and
• the second cross-sectional profile is different than the first cross-sectional profile.