US 12,136,564 B2
Superstrate and method of making it
Fen Wan, Austin, TX (US); and Weijun Liu, Cedar Park, TX (US)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Mar. 30, 2020, as Appl. No. 16/834,465.
Prior Publication US 2021/0305082 A1, Sep. 30, 2021
Int. Cl. H01L 21/687 (2006.01); H01L 21/02 (2006.01); H01L 21/768 (2006.01)
CPC H01L 21/68757 (2013.01) [H01L 21/02282 (2013.01); H01L 21/76804 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A superstrate comprising a superstrate blank and a coating overlying an outer surface of the superstrate blank, wherein
the superstrate blank comprises a central region and a tapered edge region;
the tapered edge region of the superstrate blank has an average taper angle of not greater than 8 degrees relative to a radial direction of the superstrate blank;
the coating is overlying the central region and at least a portion of the tapered edge region of the superstrate blank; and
the superstrate is configured for planarizing a top surface of a formable material positioned on a substrate when bringing the superstrate in contact with the formable material.