| abstract |
An etching method according to an embodiment includes forming a catalyst layer made of a first noble metal or the combination of the second noble metal and the metal other than noble metals on a surface made of a semiconductor, the catalyst layer including a first portion and a second portion, the first portion covering at least a part of the surface, the second portion being located on the first portion, having an apparent density lower than that of the first portion, and being thicker than the first portion; and supplying an etchant to the catalyst layer to cause an etching of the surface with an assist from the catalyst layer as a catalyst. |