Specific Process Knowledge/Lithography/EBeamLithography: Difference between revisions
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= Alignment of exposure to existing pattern on wafer = | = Alignment of exposure to existing pattern on wafer = | ||
If you need to align an exposure to an existing pattern on a wafer you need wafer marks (or global marks). | |||
'''Please note that manual alignment (using the SEM) is no longer allowed.''' You should use semi-automatic alignment only. In rare cases where semi-automatic alignment is impossible, you should remove the resist around the wafer marks before loading the wafer/chip into the machine. | '''Please note that manual alignment (using the SEM) is no longer allowed.''' You should use semi-automatic alignment only. In rare cases where semi-automatic alignment is impossible, you should remove the resist around the wafer marks before loading the wafer/chip into the machine. | ||
[[Image:P and Q marks.png|right|250px]] | [[Image:P and Q marks.png|right|250px]] | ||