Etching method, damage layer removal method, and storage medium

An etching method includes preparing a substrate having an etching target portion formed on a silicon-containing portion, plasma-etching the etching target portion of the substrate into a predetermined pattern by plasma of a processing gas containing a CF-based gas, and removing a damage layer formed due to implantation of C and F into the silicon-containing portion exposed at a bottom of the predetermined pattern by the plasma etching. The removing of the damage layer includes forming an oxide of the damage layer by supplying oxygen-containing radicals and fluorine-containing radicals and oxidizing the damage layer with the oxygen-containing radicals while etching the damage layer with the fluorine-containing radicals, and removing the oxide by a radical treatment or a chemical treatment with a gas.