US 11,658,196 B2
Semiconductor image sensor
Keng-Yu Chou, Kaohsiung (TW); Wei-Chieh Chiang, Changhua County (TW); Chen-Jong Wang, Hsinchu County (TW); Chien-Hsien Tseng, Hsinchu (TW); and Kazuaki Hashimoto, Hsinchu County (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD., Hsinchu (TW)
Filed on Sep. 30, 2020, as Appl. No. 17/39,614.
Application 17/039,614 is a continuation of application No. 16/706,189, filed on Dec. 6, 2019, granted, now 10,797,096.
Application 16/706,189 is a continuation of application No. 15/928,748, filed on Mar. 22, 2018, granted, now 10,510,788, issued on Dec. 17, 2019.
Claims priority of provisional application 62/579,474, filed on Oct. 31, 2017.
Prior Publication US 2021/0020670 A1, Jan. 21, 2021
Int. Cl. H01L 27/146 (2006.01)
CPC H01L 27/1463 (2013.01) [H01L 27/1464 (2013.01); H01L 27/14629 (2013.01); H01L 27/14612 (2013.01); H01L 27/14621 (2013.01); H01L 27/14627 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A back side illumination (BSI) image sensor comprising:
a substrate comprising a front side and a back side opposite to the front side;
a plurality of pixel sensors;
a first isolation grid disposed in the substrate and separating the plurality of pixel sensors from each other;
a first reflective grid disposed over the first isolation grid on the back side of the substrate;
a dielectric layer covering sidewalls of the first isolation grid and sidewalls of the first reflective grid;
a second isolation grid disposed over the back side of the substrate and overlapping the reflective grid from a plan view; and
a second reflective grid disposed between the second isolation grid and the substrate,
wherein a width of the second isolation grid is greater than a width of the first reflective grid.