[14p-PB2-1~11] 3.13 Semiconductor optical devices

[14p-PB2-7] Effects of an electron blocking layer on the dark current reduction in the carrier multiplication-type c-Se-stacked 8K CMOS image sensors

〇Shigeyuki Imura¹, Keitada Mineo¹, Toshiki Arai¹, Toshihisa Watabe¹, Kazunori Miyakawa¹, Misao Kubota¹, Keisuke Nishimoto², Mutsumi Sugiyama², Masakazu Nanba¹ (1.NHK STRL, 2.Tokyo Univ. of Sci.)

Keywords:8K CMOS image sensor, crystalline selenium, nickel oxide

To meet the demands of recent high definition imaging systems, the number of pixels of the image sensor has increased. Owing to the reduced pixel size of the image sensor, the amount of light received per pixel has significantly decreased. To solve the problems, we have been developed the high sensitivity CMOS image sensors overlaid with a crystalline selenium (c-Se)-based photoconversion layer. In terms of the dark current reduction under high electric field, it is important to suppress the electron injection from an external electrode. In this study, with the fabricated stacked 8K CMOS image sensors using a p-type wide bandgap nickel oxide electron blocking layer, we successfully decreased the dark current to less than 1/30, and obtained a clear captured image of the 8K image sensors in the carrier multiplication region.