Etching method

A method of etching a first region and a second region of a processing target object at the same time, the first region including a multilayered film in which silicon oxide films and silicon nitride films are alternately stacked on top of each other, the second region including a silicon oxide film having a thickness larger than a thickness of the silicon oxide film of the first region, and the processing target object having a mask provided with openings on the first region and the second region, the method comprising:

• generating plasma of a first processing gas containing a fluorocarbon gas and a hydrofluorocarbon gas within a processing vessel of a plasma processing apparatus into which the processing target object is carried to etch the first region and the second region simultaneously;
• and
• generating plasma of a second processing gas containing a hydrogen gas, a hydrofluorocarbon gas and a nitrogen gas within the processing vessel of the plasma processing apparatus,
• wherein the generating of the plasma of the first processing gas and the generating of the plasma of the second processing gas are repeated alternately.