US 12,278,255 B2
Thin film obscurant for microelectronics
Michael K. Burkland, Tucson, AZ (US); Sean P. Kilcoyne, Lompoc, CA (US); and Peter Bellus, Tucson, AZ (US)
Assigned to Raytheon Company, Arlington, VA (US)
Filed by Raytheon Company, Waltham, MA (US)
Filed on Jun. 11, 2021, as Appl. No. 17/345,488.
Prior Publication US 2022/0399394 A1, Dec. 15, 2022
Int. Cl. H01L 27/146 (2006.01); H04N 5/33 (2023.01)
CPC H01L 27/14649 (2013.01) [H01L 27/14629 (2013.01); H01L 27/14685 (2013.01); H04N 5/33 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An assembly, comprising:
a first wafer including bulk material and a layer having microelectronics;
an oxide layer; and
a reflector wafer bonded to the first wafer, wherein the reflector wafer comprises a thin film having reflectance characteristics to prevent imaging of the microelectronics via light through the bulk material,
wherein the assembly includes, in order, the thin film, the oxide layer, the bulk material, and the layer of microelectronics,
wherein the thin film comprises a first layer of hafnium dioxide on a side of the thin film contacting air, and
wherein the thin film further comprises at least one layer of polysilicon and at least one layer of silicon dioxide.