US 12,191,338 B2
Image sensor device and methods of forming the same
Keng-Ying Liao, Hsinchu (TW); Huai-jen Tung, Hsinchu (TW); Chih Wei Sung, Hsinchu (TW); Po-zen Chen, Hsinchu (TW); Yu-chien Ku, Hsinchu (TW); Yu-Chu Lin, Hsinchu (TW); Chi-Chung Jen, Hsinchu (TW); Yen-Jou Wu, Hsinchu (TW); and S. S. Wang, Hsinchu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company Limited, Hsinchu (TW)
Filed on Jul. 26, 2022, as Appl. No. 17/873,512.
Application 17/873,512 is a division of application No. 16/851,643, filed on Apr. 17, 2020, granted, now 11,652,127.
Prior Publication US 2022/0359606 A1, Nov. 10, 2022
Int. Cl. H01L 27/146 (2006.01)
CPC H01L 27/14636 (2013.01) [H01L 27/1464 (2013.01); H01L 27/14683 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for fabricating semiconductor devices, comprising:
forming, over a first surface of a semiconductor layer, a plurality of pixels configured to absorb radiation from a second surface of the semiconductor layer, the second surface of the semiconductor layer being opposite to the first surface of the semiconductor layer;
forming a device layer over the first surface of the semiconductor layer;
forming a metallization layer over the device layer;
forming, through the second surface of the semiconductor layer, a recess laterally separated from the plurality of pixels;
forming a spacer layer extending along inner sidewalls of the recess;
forming a second oxide layer over the second surface with the spacer layer sandwiched between the inner sidewalls and the second oxide layer;
etching the second oxide layer and a portion of the device layer to expose a portion of the metallization layer; and
forming a pad structure electrically coupled to the exposed portion of the metallization layer.