Patent ID: 10957554

Abstract:
Disclosed is a dry etching method for etching a metal film on a substrate with the use of an etching gas, wherein the etching gas contains a β-diketone and first and second additive gases; wherein the metal film contains a metal element capable of forming a complex with the β-diketone; wherein the first additive gas is at least one kind of gas selected from the group consisting of NO, NO2, O2 and O3; wherein the second additive gas is at least one kind of gas selected from the group consisting of H2O and H2O2; wherein the amount of the β-diketone contained is 10 vol % to 90 vol % relative to the etching gas; and wherein the amount of the second additive gas contained is 0.1 vol % to 15 vol % relative to the etching gas. The etching rate of the metal film is increased by this etching method.