| 摘要 |
The purpose of the prevent invention is to provide a photomask blank with a small warpage variation after a photomask manufacturing process is completed. In a process for manufacturing the photomask blank having a laminate including at least one kind of a functional transparent layer on a transparent substrate with regard to an exposure beam, the present invention includes a process for forming at least one kind of the functional transparent layer on the transparent substrate, a process for performing a flash irradiation process if the absolute value of warpage on the substrate of the functional transparent layer is 0.1��or over, one process among three processes forming the laminate by laminating a functional layer different from the functional transparent layer is performed and then a thermal process is performed at least one time. Firstly, a phase shift layer is formed (S101). A thermal process is performed in a temperature of 260 to 320 for four hours or more (S102). A flash irradiation process is performed (S103). A light shield layer is formed on the phase shift layer after the process is completed (S104). A photomask blank is obtained (S105). [Reference numerals] (S101) Form a phase shift layer;(S102) Heat treating;(S103) flash irradiation process;(S104) Form light shield layer;(S105) Photomask blank |
