Patent ID: 9536707
Date: 2017-01-03
CPC Classifications: H01J,H01L

Claim:
1. An etching method of etching a multilayered film including a first film and a second film that have different permittivities and are alternately stacked on top of each other, the etching method comprising: preparing, within a processing vessel of a plasma processing apparatus, a processing target object having the multilayered film and a mask formed on the multilayered film; and etching the multilayered film by generating plasma within the processing vessel of the plasma processing apparatus, wherein in the etching of the multilayered film, a first processing gas containing a hydrogen gas, a hydrogen bromide gas, a fluorine-containing gas and a hydrofluorocarbon gas and a second processing gas containing a hydrocarbon gas and a fluorocarbon gas are supplied from a first supply unit configured to supply a gas toward a central region of the processing target object and from a second supply unit configured to supply a gas toward an outer region than the central region such that a flow rate ratio of the second processing gas to the first processing gas supplied from the first supply unit is same as a flow rate ratio of the second processing gas to the first processing gas supplied from the second supply unit; the second processing gas is supplied from either one of the first supply unit and the second supply unit such that the flow rate ratio of the second processing gas to the first processing gas supplied from the first supply unit becomes different from the flow rate ratio of the second processing gas to the first processing gas supplied from the second supply unit; and the first processing gas and the second processing gas are excited.