Patent ID: 8043971

Claim:
A plasma etching method for use in a plasma processing apparatus for performing an etching processing on a substrate mounted on a mounting table in a processing vessel by plasma of a processing gas, wherein the plasma processing apparatus comprises: a ring member formed of an insulating material, installed to surround the substrate on the mounting table; and a DC power supply, the plasma etching method comprising the steps of: mounting the substrate on the mounting table in the processing vessel; executing a first etching process on an insulating layer of the substrate by generating plasma in the processing vessel under a condition in which a first DC voltage is applied to an electrode embedded inside the ring member along a diametrical direction thereof; and executing a second etching process on a silicon layer of the substrate by generating plasma in the processing vessel under a condition in which a second DC voltage is applied to the electrode, wherein the DC power supply applies the first DC voltage and the second DC voltage to the electrode to adjust a plasma sheath region above the ring member.