Plasma etching method

Abstract

The present invention provides a plasma etching method with an EUV-exposed resist capable of preventing variations of device feature dimensions. The plasma etching method of the present invention is to plasma-etch a target material with a multilayer resist that serves as a mask and composed of an EUV-exposed resist, an antireflective coating, an inorganic film and an organic film. The plasma etching method includes a first step of depositing a deposition film on a surface of the EUV-exposed resist before the antireflective coating is etched, a second step of etching the deposition film deposited on the antireflective coating and the antireflective coating with a gas mixture of Cl2 gas, HBr gas and N2 gas after the first step, a third step of etching the inorganic film after the second step, and a fourth step of etching the organic film after the third step.

Dependencies are inferred from the claim text.