US 12,345,887 B2
Techniques for controlling overburden planarization
Ankit Vora, Bothell, WA (US); Keren Zhang, Woodinville, WA (US); Matthew E. Colburn, Woodinville, WA (US); Feyza Dundar Arisoy, Redmond, WA (US); and Igor Abramson, Duvall, WA (US)
Assigned to Meta Platforms Technologies, LLC, Menlo Park, CA (US)
Filed by Meta Platforms Technologies, LLC, Menlo Park, CA (US)
Filed on Jan. 10, 2022, as Appl. No. 17/571,990.
Claims priority of provisional application 63/138,084, filed on Jan. 15, 2021.
Prior Publication US 2024/0151971 A1, May 9, 2024
Int. Cl. G02B 27/01 (2006.01); G02B 1/14 (2015.01); G02B 5/18 (2006.01)
CPC G02B 27/0172 (2013.01) [G02B 1/14 (2015.01); G02B 5/1866 (2013.01); G02B 2027/0178 (2013.01); G02B 2027/0194 (2013.01); Y10T 428/24364 (2015.01)] 5 Claims
OG exemplary drawing
 
1. An optical device comprising:
a surface-relief grating including a plurality of ridges and a plurality of grooves, wherein the plurality of grooves is characterized by a depth greater than 50 nm; and
an overcoat layer filled in the plurality of grooves and on top of the plurality of ridges, wherein:
the overcoat layer includes an organic material;
a thickness of the overcoat layer on top of the plurality of ridges is equal to or less than 20 nm and is greater than 0 nm; and
a surface peak-to-valley height of a top surface of the overcoat layer is equal to or less than 5 nm and is greater than 0 nm.