US 11,791,362 B2
Image sensor and method of fabricating the same
Sang-Hoon Kim, Seongnam-si (KR); and Kwan Hee Lee, Suwon-si (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed by Samsung Electronics Co., Ltd., Suwon-si (KR)
Filed on Aug. 31, 2020, as Appl. No. 17/7,332.
Claims priority of application No. 10-2020-0010861 (KR), filed on Jan. 30, 2020.
Prior Publication US 2021/0242267 A1, Aug. 5, 2021
Int. Cl. H01L 31/101 (2006.01); H01L 27/146 (2006.01)
CPC H01L 27/14636 (2013.01) [H01L 27/1463 (2013.01); H01L 27/14603 (2013.01); H01L 27/14621 (2013.01); H01L 27/14627 (2013.01); H01L 27/14689 (2013.01)] 17 Claims
OG exemplary drawing
 
1. An image sensor including a sensor array region and a pad region, which is disposed outside the sensor array region, the image sensor comprising:
a first substrate including a first surface, upon which light is incident, and a second surface, which is opposite to the first surface;
a first isolation film in the first substrate at the sensor array region, the first isolation film defining a plurality of unit pixels;
a second substrate including a third surface, which faces the second surface of the first substrate, and a fourth surface, which is opposite to the third surface;
a wiring structure between the second and third surfaces, the wiring structure including an interlayer insulating film and a wiring in the interlayer insulating film;
a pad trench in the pad region, the pad trench exposing the wiring through the first substrate;
a bonding terminal in the pad trench, the bonding terminal being connected to the wiring; and
a second isolation film in the first substrate at the pad region, the second isolation film being adjacent to the pad trench,
wherein widths of each of the first and second isolation films decrease in a direction from the second surface to the first surface,
wherein the first and second isolation films include respective oxide films, which extend along substrate trenches in the first substrate,
wherein each of the first and second isolation films further includes a filling film, which fills the substrate trenches, on the respective oxide films, and
wherein the substrate trenches extend from the first surface to the second surface.