Patent ID: 7943523

Claim:
A plasma etching method for plasma-etching an anti-reflective coating formed on a target object, comprising the steps of: placing the target object into a processing chamber including a first electrode and a second electrode facing each other, the second electrode being provided with an electrostatic chuck and the target object being disposed on the electrostatic chuck, wherein the target object includes an etching target film, the anti-reflective coating and a patterned photoresist film sequentially formed in that order on a substrate; applying a first DC voltage to the electrostatic chuck to electrostatically absorb the target object thereto; introducing a processing gas into the processing chamber; generating a plasma by applying a high frequency power to one of the first electrode and the second electrode and etching the anti-reflective coating by using the patterned photoresist film as a mask; and applying a second DC voltage to one of the first electrode and the second electrode while etching the anti-reflective coating such that an etched pattern dimension of the etched anti-reflective coating is smaller by a predetermined value than a pattern dimension of the patterned photoresist film, wherein the second DC voltage is applied to the first electrode to sputter a polymer adhered to the first electrode while etching the anti-reflective coating so that the sputtered polymer is attached to a sidewall of an etched portion of the anti-reflective coating.