Two-piece rf shield design

A semiconductor processing chamber, comprising:

• a chamber body;
• a substrate support assembly disposed within the chamber body, the substrate support assembly comprising a support plate seated atop a support stem;
• a lid plate seated atop the chamber body;
• a thermal choke plate seated atop the lid plate;
• a pumping plate seated atop the thermal choke plate;
• and
• a radio frequency (RF) shield seated atop the thermal choke plate and the pumping plate, the RF shield extending about a peripheral edge of the support plate, the RF shield comprising:
• a lower annular member;
• and
• an upper annular member seated atop the lower annular member, the upper annular member defining a lip that protrudes radially outward from an outer surface of the upper annular member, wherein each of the lower annular member and the upper annular member comprises a dielectric material.