Compensation of within-subfield linewidth variation in e-beam projection lithography

摘要

A method for improving image fidelity on a resist. The method adjusts the intensity distribution of the electron beam such that the feature size at the edges and the center of a subfield have a same width "w". This is accomplished by intentionally increasing the incident intensity where the images are small (more pronounced blurring), and intentionally decreasing the incident intensity where the images are large (less pronounced blurring). This can be achieved, for example, by maintaining a cathode temperature profile which increases or decreases radially by an appropriate amount.