Abstract: A scanning lithography tool exposes a medium in a raster scan. The raster scan is a multi-pass scan in which the shape of the beam, while fixed for any one pass, is altered between passes. Thus, certain pixels are exposed in one or more scans using a Gaussian (round) beam while other pixels are exposed in separate scans using, for instance, a shaped (e.g., square or rectangular) shaped beam. Beam shape here refers to the cross-sectional shape of the beam as incident on the medium. This process, especially when the shaped beam is applied at the corners and slanted edges of a feature being exposed, has been found to substantially reduce the problem of edge blur otherwise typical of raster scan lithography. This process is applicable to both electron beam and laser beam raster scanning lithography.