The invention discloses an etching method, which comprises the following steps of firstly providing a substrate, wherein a first area and a second area adjacent to the first area are defined on the substrate; forming a material layer on the substrate and forming a patterned mask on the material layer, wherein the patterned mask comprises a first part and a second part; the first part covers the material layer located in the first area; the second part corresponds to the second area; the second part comprises a lattice structure; the lattice structure comprises a plurality of openings and a plurality of shielding parts; the material layer located in the second area is exposed through the openings; and the shielding parts are located between the adjacent openings and cover the material layerin the second area; and carrying out isotropic etching to remove the material layer exposed through the openings and the material layer covered with the shielding parts.