To provide an apparatus for adhering a photomask in which production of an air reservoir can be definitely prevented, the evacuation time is significantly reduced and the production efficiency can be improved.
A sealed space 27 between a metal thin plate 11 and a photomask 21 opposing to the metal thin plate 11 is evacuated to tightly adhere the metal thin plate 11 with the photomask 12. When the sealed space 27 is evacuated, the evacuation pressure is stepwise increased, with the evacuation pressure in the initial state controlled to 1.5% to 2.5% of the maximum evacuation pressure as possible and the evacuation time in the initial stage controlled to 40% to 60% of the total evacuation time. By optimizing the evacuation pressure and the evacuation time in the initial stage, production of the air reservoir is surely prevented as well as the evacuation time is reduced and the production efficiency is improved.
KAWASAKI TOMOYOSHI
KOTANI KAZUYOSHI
Satoshi Kabazawa
Next Patent: OPTICAL LAMINATE AND ITS MANUFACTURING METHOD