Specific Process Knowledge/Lithography/Aligners/Aligner: Maskless 03 processing: Difference between revisions
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==Back Side Alignment== | ==Back Side Alignment== | ||
[[Image:MLA150_BSA_Backside.JPG|300x300px|thumb|Image of a BSA alignment mark during alignment. The mark is 300µm wide. The blue cross-hair is ~18µm. ]] | |||
'''Overlay accuracy (spec):''' 1.0µm | '''Overlay accuracy (spec):''' 1.0µm | ||
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The alignment marks must be placed within the BSA windows. The Overview camera only shows the top side of the substrate, and cannot be used to locate the BSA marks. | The alignment marks must be placed within the BSA windows. The Overview camera only shows the top side of the substrate, and cannot be used to locate the BSA marks. | ||
{| cellpadding="2" style="border: 2px solid darkgray;" align="right" | |||
! width="320" | | |||
! width="320" | | |||
! width="320" | | |||
|- border="0" align="center" | |||
|[[Image:MLA150 BSA 2inch.JPG|300px]] | |||
|[[Image:MLA150_BSA_4inch.JPG|300px]] | |||
|[[Image:MLA150_BSA_6inch_mod.jpg|300px]] | |||
|- align="center" | |||
| BSA marks positionned at x = ±20mm on a 2" wafer || BSA marks positionned at x = ±40mm on a 4" wafer || BSA marks positionned at x = ±50mm on a 6" wafer | |||
|} | |||
<br clear="all" /> | <br clear="all" /> | ||