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AssigneeAnvik Corporation
InventorsKanti Jain, Jeffrey M. Hoffman
Estimating the term…
In numerous applications of large-area patterning systems, the preferred image magnification is unity. However, in some applications, the size of the substrate may change slightly due to various thermal and/or chemical processing steps. To compensate for scale changes of the substrate, the magnification of the imaging system must vary slightly from unit magnification (typically by a fraction of a percentage) so that a layer already patterned on the substrate will have, after processing, proper image registration with the subsequent layer. This disclosure describes a lithography system for exposing large substrates at high imaging resolution and high exposure throughput, and specifically relates to a scan-and-repeat patterning system that employs a unitary mask-substrate stage and enables projection imaging of a substrate with capability to control the image magnification to compensate for changes of substrate dimensions occurring as a result of previous process steps. A combination of optical and mechanical compensation is used to provide the necessary magnification control, including anamorphic magnification variation in which the fine adjustment is of different magnitudes in x and y dimensions. The optical control is provided by a projection lens with anamorphic magnification adjustment capability. The mechanical compensation is performed by providing a differential relative velocity between the mask and substrate during scanning.
A large-area, high-throughput, high-resolution, scan-and-repeat, projection imaging system for replicating a pattern on a mask onto a corresponding pattern area segment of a substrate having a set of one or more segments, said system including a projection lens of a known characteristic magnification of substantially unity, characterized by:
Dependencies are inferred from the claim text.