US 11,990,493 B2
Image sensor device with reflective structure
Chun-Chieh Fang, Zhongpu Township (TW); Ming-Chi Wu, Kaohsiung (TW); Ji-Heng Jiang, Tainan (TW); Chi-Yuan Wen, Tainan (TW); Chien-Nan Tu, Kaohsiung (TW); Yu-Lung Yeh, Kaohsiung (TW); Shih-Shiung Chen, Tainan (TW); and Kun-Yu Lin, Tainan (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed on May 18, 2022, as Appl. No. 17/747,514.
Application 16/277,375 is a division of application No. 15/638,971, filed on Jun. 30, 2017, granted, now 10,211,244, issued on Feb. 19, 2019.
Application 17/747,514 is a continuation of application No. 16/924,538, filed on Jul. 9, 2020, granted, now 11,342,372.
Application 16/924,538 is a continuation of application No. 16/277,375, filed on Feb. 15, 2019, granted, now 10,734,427, issued on Aug. 4, 2020.
Prior Publication US 2022/0278159 A1, Sep. 1, 2022
Int. Cl. H01L 21/02 (2006.01); H01L 27/146 (2006.01)
CPC H01L 27/14629 (2013.01) [H01L 27/14621 (2013.01); H01L 27/1463 (2013.01); H01L 27/14645 (2013.01); H01L 27/14685 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An image sensor device, comprising:
a semiconductor substrate having a front surface, a back surface opposite to the front surface, and a light-sensing region close to the front surface;
an insulating layer covering the back surface and extending into the semiconductor substrate, wherein the insulating layer surrounds the light-sensing region, and a thickness of an upper portion of the insulating layer in the semiconductor substrate increases in a direction away from the front surface;
a protection layer between the insulating layer and the semiconductor substrate, wherein the protection layer has a first refractive index, and the first refractive index is less than a second refractive index of the semiconductor substrate and greater than a third refractive index of the insulating layer, and the protection layer conformally and continuously covers the back surface and extends into the semiconductor substrate; and
a reflective structure surrounded by insulating layer in the semiconductor substrate, wherein the reflective structure has a first end and a second end, the second end is between the first end and the front surface, and a middle portion of the reflective structure is wider than the first end or the second end.