摘要 |
A photolithography lens system is disclosed. The system has several elements all perpendicularly aligned to an optical axis. The elements include a light source that generates an exposing light, a first lens that has a front focal plane and a pupil plane, and a binary mask between the light source and the first lens. The binary mask is placed at the front focal plane of the first lens. A pupil filter is placed at the pupil plane. Finally, a second lens is provided that has a front focal plane at substantially the same position as the pupil plane. The second lens also has a back focal plane where a semiconductor wafer is placed.
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