| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a photomask having a fine transfer pattern with high accuracy.SOLUTION: A method for manufacturing a photomask is provided, which includes: a step of preparing a photomask blank having an underlay film, an intermediate film, an overlay film, and a photoresist film formed on a transparent substrate; a step of subjecting the photoresist film to drawing and preliminary development to form a first resist pattern; a preliminary etching step of etching the overlay film by using the first resist pattern as a mask, and further etching the intermediate film by using the first resist pattern or the etched overlay film as a mask; a step of subjecting the first resist pattern to additional development to form a second resist pattern; and a post-etching step of subjecting the overlay film to additional etching by using the second resist pattern as a mask, and further etching the underlay film by using the etched intermediate film as a mask. |
