US 12,300,529 B2
Alignment of targets on opposite sides of a substrate
Peter D. Brewer, Westlake Village, CA (US); Sevag Terterian, Lake Balboa, CA (US); Diego Eduardo Carrasco, Los Angeles, CA (US); and Charbel Abijaoude, Newbury Park, CA (US)
Assigned to The Boeing Company, Arlington, VA (US)
Filed by The Boeing Company, Chicago, IL (US)
Filed on May 18, 2022, as Appl. No. 17/663,858.
Prior Publication US 2023/0377929 A1, Nov. 23, 2023
Int. Cl. H01L 21/68 (2006.01); H01L 21/48 (2006.01)
CPC H01L 21/681 (2013.01) [H01L 21/486 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method to align targets on opposite sides of a substrate, the method comprising:
forming a first via pattern in a protective layer on a first side of the substrate, wherein:
the substrate includes a second side opposite the first side;
the first via pattern is a first pixelated version of a first alignment target; and
the first alignment target is optically recognizable by an automated alignment system;
etching a plurality of first vias through the substrate to the second side in the first via pattern, wherein the first via pattern is optically recognizable by the automated alignment system as the first alignment target on both the first side and the second side of the substrate;
fabricating a first circuit on the first side;
etching one or more second vias through the substrate from the second side to the first side;
filling the one or more second vias with a conductor electrically coupled to the first circuit; and
fabricating a second circuit electrically coupled to the conductor on the second side.