Mask blank and mask
View Patent ↗A mask blank is equipped with a thin film that forms a mask pattern formed on a substrate and a chemically amplified type resist film that is formed above the thin film. In the mask blank, a protective film that prevents movement of a substance that inhibits a chemical amplification function of the resist film from a bottom portion of the resist film to inside the resist film is provided between the thin film and the resist film. The mask blank suppresses the error of the line width dimension of the transfer pattern formed on the substrate to the design dimension of the transfer pattern line width of the transfer mask (actual dimension error) and also suppress linearity up to 10 nm.
1. A mask blank comprising:
a thin film that forms a mask pattern formed on a substrate; and
a chemically amplified resist film that is formed above the thin film;
wherein
a resin film with a thickness equal to or more than 2 nm and up to 25 nm and a density equal to or more than 1.4 g/cm 3 is provided between the thin film and the resist film, where the resin film is made of a material that is etchable with an etchant used in etching of the thin film, and the film density is determined using grazing incidence X-ray reflectivity technique (GIXR).
2. The mask blank according to claim 1 , wherein the resin film prevents movement of a substance that inhibits a chemical amplification function of the resist film from a bottom portion of the resist film to inside the resist film.
3. The mask blank according to claim 1 , wherein the resin film is configured to be removed in a patterning process of the thin film.
4. The mask blank according to claim 1 , wherein the thin film is a metal film.
5. The mask blank according to claim 1 , wherein the thin film is formed by a reactive sputtering technique.
6. The mask blank according to claim 1 , wherein the mask blank is a mask blank prior to formation of the chemically amplified resist film.
7. A transfer mask including a transfer pattern formed on a substrate by patterning the thin film in the mask blank according to claim 1 .
8. The mask blank according to claim 1 , wherein the thickness of the resin film is equal to or more than 2 nm and up to 20 nm, and the density of the resin film is equal to or more than 1.6 g/cm 3 .
9. The mask blank according to claim 1 , wherein the thickness of the resin film is equal to or more than 5 nm and up to 20 nm, and the density of the resin film is equal to or more than 1.7 g/cm 3 .