Plasma etching method

A plasma etching method comprising supplying both hexafluoroisopropanol (HFIP) gas and argon (Ar) gas to a plasma chamber receiving an etching target therein, thereby to plasma-etch the etching target,

• wherein the plasma chamber is connected to a canister containing hexafluoroisopropanol (HFIP) in a liquid phase by a chamber connecting line, and is connected to an argon gas injection line different from the chamber connecting line, and
• wherein the supplying comprises:
• generating the HFIP gas by heating the canister at a first temperature higher than a boiling point of the HFIP and heating the chamber connecting line at a second temperature higher than the first temperature, and
• supplying the generated HFIP gas to the plasma chamber through the chamber connecting line and supplying the argon gas to the plasma chamber through the argon gas injection line,
• wherein the Ar gas is supplied to the plasma chamber at a flow rate being in a range of 67% to 80% of a total flow rate of the Ar gas and the HFIP gas.