US Patent 11791194 Substrate processing apparatus and method of processing a substrate

A substrate processing apparatus including a process chamber; a susceptor in the process chamber; and an inner edge ring and an outer edge ring on the susceptor, wherein the inner edge ring includes a semiconductor, the outer edge ring includes an insulator, an upper surface of the outer edge ring is at a higher level than an upper surface of the inner edge ring, and the outer edge ring has an overhang extending onto the inner edge ring.