Title :
A new exposure method using cover glass
Author :
Okamoto, Yoshihiko ; Ogita, Masami
Author_Institution :
GSEST, Shizuoak Univ., Hamamatsu, Japan
Abstract :
We present a new exposure method to achieve super resolution of a projection lens. The idea is based on a cover glass inserted between an optical lens and image plane. We have designed a projection lens system using a cover glass. It has found that the resolution of the projection pattern can be improved by use of a cover glass under the condition that the practical size of the projection lens is restricted. We have also set up a proto-type exposure evaluation system of reduction projection lens. It has been found that projection image of mask pattern was improved using a cover glass inserted between a projection lens and its image plane. We have also found that projection image of mask pattern was much improved by use of both phase shifting mask and a cover glass inserted between a projection lens and its image plane.
Keywords :
image resolution; lenses; optical glass; optical images; phase shifting masks; cover glass; exposure method; image plane; optical lens; pattern resolution; phase shifting mask; projection lens; Glass; Lenses; Lithography; Optical design; Optical refraction; Optical variables control; Refractive index; Resists; Software design; Ultraviolet sources;
Conference_Titel :
Industrial Electronics Society, 2005. IECON 2005. 31st Annual Conference of IEEE
Print_ISBN :
0-7803-9252-3
DOI :
10.1109/IECON.2005.1569276