US 11,894,404 B2
Method for fabricating an image sensing device having a primary grid and a second grid surrounding the primary grid
Yun-Hao Chen, Hsinchu (TW); Kuo-Yu Wu, Hsinchu County (TW); and Tse-Hua Lu, Hsinchu County (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD., Hsinchu (TW)
Filed on May 26, 2022, as Appl. No. 17/824,952.
Application 17/824,952 is a division of application No. 16/414,498, filed on May 16, 2019, granted, now 11,348,958.
Prior Publication US 2022/0293654 A1, Sep. 15, 2022
Int. Cl. H01L 27/146 (2006.01)
CPC H01L 27/14621 (2013.01) [H01L 27/1463 (2013.01); H01L 27/14603 (2013.01); H01L 27/14645 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for fabricating an optical structure, comprising:
forming a light detection region in a substrate;
forming an isolation structure at least surrounding the light detection region; and
forming a primary grid over the isolation structure, comprising:
forming a metal layer over the isolation structure;
forming a first dielectric layer over the metal layer; and
partially removing the metal layer and the first dielectric layer with a first mask by patterning;
forming a secondary grid at least partially surrounded by the primary grid laterally; and
forming a liner lining at a sidewall of the primary grid, wherein the liner is free from being in direct contact with the secondary grid.