Illumination system for lithographic projection exposure step-and-scan apparatus
AssigneeShanghai Institute of Optics And Fine Mechanics, Chinese Academy of Sciences
InventorsAijun ZENG, Liqun CHEN, Ruifang FANG, Huijie HUANG
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Abstract
Illumination system for a lithographic projection exposure step-and-scan apparatus comprising a light source, a pupil shaping unit, a field defining unit, a first lens array, a first slit array, a second lens array, a third lens array, a second slit array, a fourth lens array, a condenser lens, and a scanning drive unit sequentially arranged along the light beam propagation direction. The illumination system reduces requirements on lens processing, slit scanning speed, and slit scanning precision, therefore may be implemented more easily.
Claims7
An illumination system for a lithographic projection exposure step-and-scan apparatus, comprising
- a light source,
- a pupil shaping unit,
- a field defining unit comprising a first microlens array and a second microlens array having micro-cylindrical lenses with curved surface,
- a condenser lens,
- a first lens array,
- a first slit array comprising controlling ports,
- a second lens array,
- a third lens array,
- a second slit array,
- a fourth lens array,
- a mask, and
- a scanning driver unit comprising an output terminal,
- wherein the light source, the pupil shaping unit, the field defining unit, the first lens array, the first slit array, the second lens array, the third lens array, the second slit array, the fourth lens array, the condenser lens, and the mask are successively arranged along transmission direction of light;
- the first lens array, the second lens array, the third lens array, and the fourth lens array have the same number of lens and the same arrangement of lenses, and the corresponding axes of lens in the first lens array, the second lens array, the third lens array, and the fourth lens array are superimposed;
- the clear apertures of the first lens array, the second lens array, the third lens array, and the fourth lens array are twice more than the clear aperture of the curved surface of micro-cylindrical lens in the field defining unit;
- the output terminal of the scanning drive unit is connected with the controlling ports of the first slit array and the second slit array;
- the image plane of the second lens array and the object plane of the third lens array are superimposed;
- the image plane of the third lens array, the plane of the second slit array, and the object plane of the fourth lens array are superimposed;
- and
- the image plane of the fourth lens array and the object plane of the condenser lens are superimposed.
Dependencies are inferred from the claim text.