Manufacture of dustproof cover for photomask

Abstract

Abstract PURPOSE:To obtain easily the titled cover of a uniform thickness with high reproducibility by adhering a frame to a thin nitrocellulose film formed on a smooth substrate and by immersing the film in water to strip the substrate. CONSTITUTION:A smooth substrate such as a silicon substrate having >=lambda/4 smoothness is coated with a soln. contg. 3-15wt% nitrocellulose having 10.7- 12.2% nitrogen content by means of a spin coater under conditions of 25-30 deg.C casting temp., 5-10cc extent of casting and 500-3,000r.p.m. number of revolutions of the spinner to form a thin nitrocellulose film of 0.5-3mum thickness. A frame is adhered to the film, and the film is immersed in water for >=15min to strip the substrate. The film is then taken out of the water and dried. The thin nitrocellulose film can be stretched tight on the frame.

Inventors

• 👤 Yasunori Fukumitsu
• 👤 福光　保典
• 👤 Mitsuo Kono
• 👤 河野　満男

Bibliographic Details