Plasma etching method

Abstract

An isotropic etching process can be performed with high uniformity. A plasma etching method of etching an etching target layer containing silicon includes preparing a processing target object having the etching target layer in a processing chamber; removing an oxide film on a surface of the etching target layer by generating plasma of a first processing gas that contains a fluorocarbon gas or a fluorohydrocarbon gas but does not contain oxygen; removing a carbon-based reaction product generated when the removing of the oxide film by generating plasma of a second processing gas that does not contain oxygen; and etching the etching target layer without applying a high frequency bias power to a lower electrode serving as a mounting table configured to mount the processing target object thereon by generating plasma of a third processing gas containing a fluorocarbon gas or a fluorohydrocarbon gas with a microwave.