Specific Process Knowledge/Lithography/EBeamLithography/JBX9500Manual: Difference between revisions
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After measuring all 7 x 7 points, the machine generate a distortion correction table and measures again. This procedure is repeated until the maximum offset is as specified in 'allowable convergence value' in DISTBE or DISTMEM. | After measuring all 7 x 7 points, the machine generate a distortion correction table and measures again. This procedure is repeated until the maximum offset is as specified in 'allowable convergence value' in DISTBE or DISTMEM. | ||
DISTBE generates the correction table by cubic approximation between measurement points. Therefore, some measurement points will be far from the curve of cubic function. This way is nice between each measurement point but no good for measurement point. | |||
DISTMEM generates the correction table by collinear approximation. This means that the correction value between each measurement point is corrected linearly. This way is nice for each measurement point but no good between each measurement point. | |||
We empirically found that executing DISTMEM before executing DISTBE gives the best results. | |||
If the convergence value is not met after 3-4 measurements, the scan position on the BE mark should be changed as described in troubleshooting. | If the convergence value is not met after 3-4 measurements, the scan position on the BE mark should be changed as described in troubleshooting. | ||