06211944 is referenced by 84 patents and cites 24 patents.

A projection exposure apparatus and method that includes an illumination system and a projection system. The illumination system may include a plurality of optical integrators that form different secondary light sources. The illumination system illuminates the pattern with light from a secondary light source selected based on the pattern. The projection system projects an image of the pattern on a predetermined plane. The projection exposure apparatus may also include a light shielding device having a cross-like portion extending in first and second directions defined by the components of the pattern. Even further, the projection exposure apparatus may include four off-axis secondary light sources where a ratio of a numerical aperture of a light beam from each of the four secondary light sources to a numerical aperture of the projection optical system is substantially 0.1 through 0.3.

Title
Projection exposure method and apparatus
Application Number
8/472930
Publication Number
6211944 (B1)
Application Date
June 7, 1995
Publication Date
April 3, 2001
Inventor
Naomasa Shiraishi
Kawasaki
US
Agent
Oliff & Berridge
US
Assignee
Nikon Corporation
US
IPC
G03B 27/42
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