Method for manufacturing photomask blank
The present invention relates to a photomask blank obtained by forming a resist film after performing a silylation process on a silicon-containing inorganic film and provides a method for manufacturing a photomask blank having at least a silicon-containing inorganic film over a transparent substrate and a resist film on the inorganic film, comprising: forming the silicon-containing inorganic film; heat treating the formed silicon-containing inorganic film at a temperature more than 200° C. under an atmosphere containing oxygen; performing a silylation process after the heat treatment; and then forming the resist film by application. The method can inhibit generation of defects due to resist residues or the like after development.
1. A method for manufacturing a photomask blank having at least a silicon-containing inorganic film over a transparent substrate and a resist film on the inorganic film, comprising:
forming the silicon-containing inorganic film;
heat treating the formed silicon-containing inorganic film at a temperature more than 200° C. under an atmosphere containing oxygen;
performing a silylation process after the heat treatment; and then
forming the resist film by application.
2. The method for manufacturing a photomask blank according to claim 1 , wherein the heat treatment is performed at a temperature more than 400° C.
3. The method for manufacturing a photomask blank according to claim 1 , wherein the silicon-containing inorganic film further contains oxygen.
4. The method for manufacturing a photomask blank according to claim 2 , wherein the silicon-containing inorganic film further contains oxygen.
5. The method for manufacturing a photomask blank according to claim 3 , wherein the silicon-containing inorganic film is composed of silicon and oxygen.
6. The method for manufacturing a photomask blank according to claim 4 , wherein the silicon-containing inorganic film is composed of silicon and oxygen.
7. The method for manufacturing a photomask blank according to claim 1 , wherein a chromium-containing inorganic film is formed before forming the silicon-containing inorganic film.
8. The method for manufacturing a photomask blank according to claim 2 , wherein a chromium-containing inorganic film is formed before forming the silicon-containing inorganic film.
9. The method for manufacturing a photomask blank according to claim 3 , wherein a chromium-containing inorganic film is formed before forming the silicon-containing inorganic film.
10. The method for manufacturing a photomask blank according to claim 4 , wherein a chromium-containing inorganic film is formed before forming the silicon-containing inorganic film.
11. The method for manufacturing a photomask blank according to claim 5 , wherein a chromium-containing inorganic film is formed before forming the silicon-containing inorganic film.
12. The method for manufacturing a photomask blank according to claim 6 , wherein a chromium-containing inorganic film is formed before forming the silicon-containing inorganic film.
13. The method for manufacturing a photomask blank according to claim 7 , wherein a silicon-containing phase shift film is formed on the transparent substrate before forming the chromium-containing inorganic film.
14. The method for manufacturing a photomask blank according to claim 8 , wherein a silicon-containing phase shift film is formed on the transparent substrate before forming the chromium-containing inorganic film.
15. The method for manufacturing a photomask blank according to claim 9 , wherein a silicon-containing phase shift film is formed on the transparent substrate before forming the chromium-containing inorganic film.
16. The method for manufacturing a photomask blank according to claim 10 , wherein a silicon-containing phase shift film is formed on the transparent substrate before forming the chromium-containing inorganic film.
17. The method for manufacturing a photomask blank according to claim 11 , wherein a silicon-containing phase shift film is formed on the transparent substrate before forming the chromium-containing inorganic film.
18. The method for manufacturing a photomask blank according to claim 12 , wherein a silicon-containing phase shift film is formed on the transparent substrate before forming the chromium-containing inorganic film.
19. The method for manufacturing a photomask blank according to claim 1 , wherein the silicon-containing inorganic film is a hard mask.
20. The method for manufacturing a photomask blank according to claim 18 , wherein the silicon-containing inorganic film is a hard mask.
21. The method for manufacturing a photomask blank according to claim 1 , wherein hexamethyldisilazane is used for the silylation process.
22. The method for manufacturing a photomask blank according to claim 20 , wherein hexamethyldisilazane is used for the silylation process.