US 12,136,638 B2
Semiconductor devices for image sensing
Chin-Chia Kuo, Tainan (TW); Jhy-Jyi Sze, Hsin-Chu (TW); Tung-Ting Wu, Taipei (TW); and Yimin Huang, Hsinchu (TW)
Assigned to Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Ltd., Hsin-Chu (TW)
Filed on Jul. 20, 2021, as Appl. No. 17/380,202.
Application 17/380,202 is a continuation of application No. 15/962,130, filed on Apr. 25, 2018, granted, now 11,075,242.
Claims priority of provisional application 62/590,864, filed on Nov. 27, 2017.
Prior Publication US 2021/0351218 A1, Nov. 11, 2021
Int. Cl. H01L 27/146 (2006.01); H01L 31/0232 (2014.01); H01L 31/0236 (2006.01)
CPC H01L 27/14629 (2013.01) [H01L 27/14607 (2013.01); H01L 27/1462 (2013.01); H01L 27/1463 (2013.01); H01L 27/1464 (2013.01); H01L 27/14685 (2013.01); H01L 31/02327 (2013.01); H01L 31/02363 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A semiconductor device, comprising:
a semiconductor substrate;
a grid structure extending from a first side of the semiconductor substrate to within the semiconductor substrate as viewed in cross-section, the grid structure including a plurality of closed-loop grid segments that adjoin one another to form the grid structure as viewed from above;
a plurality of image sensing elements disposed within the semiconductor substrate and laterally surrounded by the closed-loop grid segments, respectively; and
a plurality of protrusions arranged along the first side of the semiconductor substrate, the plurality of protrusions being disposed over a single image sensing element of the plurality of image sensing elements and being laterally surrounded by the closed-loop grid segment of the single image sensing element, the plurality of protrusions being substantially identical to one another and having a characteristic dimension, wherein an inner edge of the closed-loop grid segment facing the image sensing element is spaced apart from a peak or valley of one of the plurality of protrusions by a flat surface corresponding to a predetermined reflective length that is based on the characteristic dimension of the plurality of protrusions.