Patent ID: 8555810

Claim:
A plasma dry etching apparatus, comprising: a process chamber; a pedestal in the process chamber, the pedestal being configured to support a wafer; a cathode electrode and a plate electrode in the process chamber, the cathode and plate electrodes being configured to apply radio-frequency (RF) power; an edge ring that is on an edge of the pedestal and that is substantially coplanar with an uppermost side of the pedestal; a coupling ring having a first side in a recess within the pedestal and a second side under the edge ring; a temperature adjuster configured to adjust a temperature of a first region of the wafer; an edge cooling unit in the coupling ring, the edge cooling unit being configured to cool the edge ring and a second region including an extreme edge of the wafer; an edge heating unit in the coupling ring, the edge heating unit being configured to heat the edge ring and the second region including the extreme edge of the wafer, wherein the edge cooling unit and the edge heating unit of the coupling ring are controlled independently from the temperature adjuster to adjust a temperature of the second region of the wafer, and wherein the first region is disposed inside the second region.