Specific Process Knowledge/Lithography/Aligners/Aligner: Maskless 02 processing: Difference between revisions
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'''Important information regarding alignment:''' | '''Important information regarding alignment:''' | ||
After alignment to the specified alignment marks, the Aligner: Maskless 02 will automatically compensate for the translation (shift) and rotation detected during the alignment. | After alignment to the specified alignment marks, the Aligner: Maskless 02 will automatically compensate for the translation (shift) and rotation detected during the alignment. However, the translation is set using only the first alignment mark. This means that if there is any run-out (gain) in the wafer, the alignment will be perfect at the first alignment position, while the second alignment position will be off by the run-out error. The central part of the print will be misaligned by half the run-out error. This is different compared to alignment in a mask aligner, where the user usually splits the run-out error between the two sides, resulting in good alignment in the center. In Aligner: Maskless 02, run-out may be compensated by activating the scaling function, which only becomes available when using 3 or more alignment positions. | ||
In order to get good alignment, it is advised to use four alignment marks for alignment, and to activate the scaling (possibly also shearing) function before starting the exposure. | |||
'''Alignment accuracy:''' | '''Alignment accuracy:''' | ||