Printing of sub resolution shots in electron beam direct write with variable shaped beam machines

The resolution of a variable shaped beam writer is typically given for the standard geometries like isolated line, isolated space, and dense (1:1) line/space pattern. It is related to the imaging power of both the tool itself as well as the resist process. In this paper we concentrate on small shots with dimensions smaller than the resolution limit, butting to a larger shot. We show experimentally that for a line resolution of 40 nm the resolution for butting sub resolution shots can be as small as 20 nm.