Patent ID: 8057634

Claim:
A plasma processing apparatus for processing an object to be processed using plasma, the apparatus comprising: a process stage for placing the object to be processed; a focus ring disposed on the process stage surrounding the object to be processed, the focus ring and the object to be processed being subjected to application of RF bias; and means for performing an equivalent circuit analysis and acquiring both a voltage on the surface of the object to be processed and the focus ring, and a sheath height on the surface of the object to be processed and the focus ring, wherein the means for performing an equivalent circuit analysis includes an equivalent circuit modeling of plasma and ion sheath based on a plasma sheath model, simultaneous analysis of a plasma load on the object to be processed in the ion sheath based on the plasma sheath model and a plasma load on the focus ring, and setting of the capacitance between the focus ring and the process stage to a value flattening an equi-potential surface within the ion sheath.