US 12,218,166 B2
CSI with controllable isolation structure and methods of manufacturing and using the same
Min-Feng Kao, Chiayi (TW); Dun-Nian Yaung, Taipei (TW); Jen-Cheng Liu, Hsin-Chu (TW); Wen-Chang Kuo, Tainan (TW); and Shih-Han Huang, Kaohsiung (TW)
Assigned to Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on Jul. 12, 2021, as Appl. No. 17/372,888.
Claims priority of provisional application 63/176,465, filed on Apr. 19, 2021.
Prior Publication US 2022/0336505 A1, Oct. 20, 2022
Int. Cl. H01L 27/14 (2006.01); H01L 27/146 (2006.01)
CPC H01L 27/1463 (2013.01) [H01L 27/14623 (2013.01); H01L 27/14636 (2013.01); H01L 27/1464 (2013.01); H01L 27/14685 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
providing a semiconductor substrate including a front side, a back side, a pixel region, a peripheral region, and photodetector pixels in an array within the pixel region;
forming a back side isolation structure including a metal grid with segments extending into the semiconductor substrate between the photodetector pixels;
forming a dielectric layer, wherein the dielectric layer is over the metal grid;
forming an opening in the dielectric layer, wherein the metal grid is exposed through the opening; and
depositing a metal layer, wherein depositing the metal layer fills the opening and simultaneously creates a contact pad on the back side, a via intersecting the metal grid, and a conductive bridge extending from the via to the contact pad on the back side;
wherein the metal grid is electrically isolated from the semiconductor substrate and electrically coupled to the contact pad.