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The method for providing a scan and repeat lithography system for high-resolution, large-field, high-speed lithography, characterized by the following steps: (a) Providing a substrate stage for holding the substrate, and capable of scanning the
substrate in one dimension, and capable of moving laterally in a direction perpendicular to the scan direction; (b) Providing a mask stage for holding the mask, and capable of scanning the mask in the same dimension as the substrate stage; (c) Providing an illumination subsystem having the desired characteristics of wavelength and intensity distribution, having aan effective source plane in the shape of a polygon, and capable of uniformly illuminating a polygon-shaped region on the mask; (d) Providing a projection subsystem for imaging the said polygon-shaped illuminated region on the mask on to the substrate, having an object-to-image reduction ratio M, having the desired image resolution, and having an image field in the shape of a polygon and of an area smaller than the desired effective image field size of the said lithography system; (e) Providing a mask which has a certain number of complete, patterned chip fields, and additional patterned areas that fall within the hexagonal illuminated region on the mask; (f) Scanning the substrate across the polygonal substrate illumination region at a certain velocity v.sub.x, and simultaneously scanning the mask in a parallel direction across the polygonal mask illumination region at a velocity Mv.sub.x ; (g) Stopping the scanning of the substrate and mask stages upon completion of a scan across the total length of the substrate along the direction of scan, moving the substrate by a certain distance in a direction perpendicular to the scan direction, and resuming the scanning of the substrate and the mask stages in directions opposite to their respective directions in step (f); (h) Providing complementary exposures in an overlap region between the areas exposed by adjacent scans in such a way that a seam in the exposure dose distribution received on the substrate is absent between the said scans, and such that the exposure dose delivered across the entire substrate is uniform; (i) Repeating steps (f)-(h) until exposure of the entire substrate is completed.
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Invalid (112)
Entry 112
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