X-ray mask and process comprising convex-concave alignment mark with alignment reflection film

An X-ray mask having an X-ray transmission film formed on the surface of a mask base, and an alignment mark formed on the surface of said X-ray transmission film wherein:

• (a) an alignment light reflection grating pattern in a grating form which is made of a first alignment light reflection film
• for reflecting the alignment light passing through said X-ray transmission film is formed on the surface of said X-ray transmission film,
• (b) an alignment light transmission film in a grating form is formed on the other surface region of said X-ray transmission film without having thereon said alignment light reflection grating pattern,
• (c) a second alignment light reflection film for reflecting the alignment light passing through said X-ray transmission film is formed on the surface of said alignment light transmission film, and
• (d) said first alignment light reflection film and said second alignment light reflection film are formed in respective different processes, and
• (e) said alignment mark is made up of a convex portion composed of said X-ray transmission film and said alignment light transmission film, and a concave portion composed of a surface region of said X-ray transmission film corresponding to the back of said alignment light reflection grating pattern.

A method of producing an X-ray mask comprising the steps of:

• (a) forming an X-ray transmission film on the surface of a mask base,
• (b) forming an alignment light reflection grating pattern, which is made up of a first alignment light reflection film for reflecting the alignment light passing through said X-ray transmission film in a grating form, on the surface of said X-ray transmission film,
• (c) forming, by the application of an etching to said X-ray transmission film wherein said alignment light reflection grating pattern is used as a resist mask, an alignment mark composed of a concave portion in a grating form that is a recess formed on said X-ray transmission film, and a convex portion made up of a flat region defined between the concave portions, on the surface of said X-ray transmission film, and
• (d) forming a second alignment light reflection film for reflecting the alignment light passing through said X-ray transmission film on the surface of said alignment mark.

A method of producing an X-ray mask comprising the steps of:

• (a) forming an X-ray transmission film on the surface of a mask base,
• (b) forming an alignment light reflection grating pattern, which is made up of a first alignment light reflection film for reflecting the alignment light passing through said X-ray transmission film in a grating form, on the surface of said X-ray transmission film,
• (c) forming, by forming an alignment light transmission film in a grating form on a region of the surface of said X-ray transmission film without having thereon said alignment light reflection grating pattern, an alignment mark composed of a convex portion made up of said X-ray transmission film and said alignment light transmission film, and a concave portion composed of a surface region of said X-ray transmission film corresponding to the back of said alignment light reflection grating pattern, and
• (d) forming a second alignment reflection film for reflecting the alignment light passing through said X-ray transmission film, on the surface of said alignment light transmission film.