A plasma etching method according to an embodiment is a method for etching a silicon-containing film by using plasma of a fluorocarbon gas. The fluorocarbon gas includes at least one selected from a first fluorocarbon which has a main chain of six or more carbons bonded in a linear manner, the main chain having a structure of single bond and double bond alternately joined, a second fluorocarbon which has a main chain of six or more carbons bonded in a linear manner, the main chain having a structure of single bond and triple bond alternately joined, and a third fluorocarbon which has a main chain of five or more carbons bonded in a linear manner, the main chain having a structure which includes double bond and triple bond.

A plasma etching method according to an embodiment is a method for etching a silicon-containing film by using plasma of a fluorocarbon gas. The fluorocarbon gas includes at least one selected from a first fluorocarbon which has a main chain of six or more carbons bonded in a linear manner, the main chain having a structure of single bond and double bond alternately joined, a second fluorocarbon which has a main chain of six or more carbons bonded in a linear manner, the main chain having a structure of single bond and triple bond alternately joined, and a third fluorocarbon which has a main chain of five or more carbons bonded in a linear manner, the main chain having a structure which includes double bond and triple bond.