Specific Process Knowledge/Lithography/EBeamLithography/EBLProcessExamples: Difference between revisions
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Example of the three different approaches for exposing arrays of circles. In all cases the red areas are the areas drawn in the mask file. The small circles indicate beam positions. | Example of the three different approaches for exposing arrays of circles. In all cases the red areas are the areas drawn in the mask file. The small circles indicate beam positions. | ||
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==SHOT mode== | |||
For both of the single shot approaches the SHOT mode defined in the SDF file should be SHOT S, rather than the normal SHOT A. | |||
SHOT A mode is used with the RESIST command to define an area dose in µC/cm2 and the beam pitch in 1/4 nm steps. The following will for instance define an area dose of 300 µC/cm2 and a beam pitch of 200 nm: | |||
RESIST 300 | |||
SHOT A, 800 | |||
As the number of beam shots in a certain area scales with the shot pitch, the dwell time is in this way determined by the combination of area dose and beam pitch. If one changes the pitch, the dwell time and hence circle size will also change. One can decouple this relation by using SHOT S mode instead. In SHOT S mode the user defines the actual dwell time and hence in SHOT S mode the RESIST command is ignored. In SHOT S mode the user can thus define the dwell time and beam pitch independently. | |||
SHOT S takes three arguments as SHOT S, t1, t2, s where t1 is area dwell time in ns, t2 is line dwell time (not applicable to JEOL 9500) and s is shot pitch in 1/4 nm steps. The following example will set a dwell time of 550 ns and a beam pitch of 150 nm | |||
SHOT S, 550, 0, 600 | |||
==Big box approach== | ==Big box approach== | ||