Patent ID: 10497580

Abstract:
A plasma etching method according to the present disclosure includes a first etching step of performing plasma etching of the silicon nitride film on the workpiece by supplying a processing gas containing a gas of a compound represented by a composition formula C3H2BrF3 including a 2-bromo-3,3,3-trifluoropropene gas, a (Z)-1-bromo-3,3,3-trifluoropropene gas, an (E)-1-bromo-3,3,3-trifluoropropene gas, and/or a 3-bromo-2,3,3-trifluoropropene gas into the processing chamber, such that a ratio CF2/F obtained by emission spectrometry of the gas of the compound represented by the composition formula C3H2BrF3 is at least 0.33 within the processing chamber.