| 摘要 |
PROBLEM TO BE SOLVED: To provide means of removing a residue generating on a mesh-like wall and on a silicon active layer surface without roughening the surface when the mesh-like wall for supporting the silicon active layer is formed by dry-etching a silicon layer from an SOI substrate.SOLUTION: A production method of a stencil mask blank is provided, including steps of: forming a hard mask layer, which has alkali durability and dry etching durability and which can be stripped with hydrofluoric acid, on a support layer surface of an SOI substrate having a three-layer structure; forming a protective layer, which has alkali durability and can be stripped with hydrofluoric acid, on an active layer surface; forming a resist pattern on the hard mask layer surface; forming an opening by dry-etching the hard mask layer and the support layer by using the resist pattern; removing a side wall residue of the support layer with a strong alkali chemical liquid; and removing an intermediate layer and the protective layer by using hydrofluoric acid. |
