By adding a second deflector-aperture stage to the electron beam column of a vector shaped mask writer in which the aperture has the shape of a cross, one gains the ability to print a parameterized “L-shaped” exposure. This is the most modest generalization of the shot shape in such machines that retains the current paradigm of exposing a non-overlapping cover of parameterized prototypical shapes. These “L” shapes occur frequently in such covers and each one patterns the equivalent of two adjacent rectangular shots. While this proposal does require hardware changes, we suggest that the substantial potential gain combined with the localized nature of the disturbance to present manufacturing pipelines justifies consideration of the technique. This paper focuses on the implications to and initial results for mask data preparation (MDP) for L-shots.
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