US Patent 9202727 Susceptor heater shim

A substrate supporting assembly in a reaction space includes a heater, a substrate support member, and a shim positioned between the heater and the substrate support member. The shim may be removably secured between the heater and the substrate support member. The shim may further include an inner surface defining a perimeter of a gap. The gap may be further defined by a bottom surface of the substrate support member and a top surface of the heater. The substrate support member may further include a shoulder positioned radially outside of a substrate support position and wherein the shim inner surface is radially aligned with the substrate support member shoulder.