Reduced dark current InAs/GaAs quantum dot photodetectors on Si(001) via spatially separated co-doping

S Shenglin Wang K Kun Zhou (Key Laboratory of Animal Virology, Ministry of Agricultural and Rural Affairs of China and Zhejiang Provincial Engineering Research Center of Animal Biological Products, Department of Veterinary Medicine, Zhejiang University College of Animal Sciences) W Wanlin Liu (Laboratory of Solid State Optoelectronics Information Technology, Institute of Semiconductors, Chinese Academy of Sciences 1 , Beijing 100083,) K Kehan Jiang (Laboratory of Solid State Optoelectronics Information Technology, Institute of Semiconductors, Chinese Academy of Sciences 1 , Beijing 100083,) H Hongyu Chai (Laboratory of Solid State Optoelectronics Information Technology, Institute of Semiconductors, Chinese Academy of Sciences 1 , Beijing 100083,) X Xiaoguang Yang T Tao Yang

Abstract

In this paper, we report reduced dark current quantum dot (QD) photodetectors (PDs) grown on Si(001) substrate by spatially separated co-doping technique, including n-type direct doping in QDs and p-type modulation doping in barrier layers. The absorption region of the QD PDs consists of eight stacked QD layers. Compared with the p-doped PDs, the co-doped PDs achieve a record-low dark current of 0.91 pA and a higher photocurrent because of additional electrons effectively passivating the defects by n-type doping. Furthermore, the co-doping technique provides two different types of impurities, which generates a stronger built-in electric field in the QDs and thereby increases the maximum 3 dB bandwidth of the QD PDs.

Article Details

Volume / Issue Vol. 128, Issue 8
Published February 23, 2026
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (7)

S

Shenglin Wang

K

Kun Zhou

Key Laboratory of Animal Virology, Ministry of Agricultural and Rural Affairs of China and Zhejiang Provincial Engineering Research Center of Animal Biological Products, Department of Veterinary Medicine, Zhejiang University College of Animal Sciences

W

Wanlin Liu

Laboratory of Solid State Optoelectronics Information Technology, Institute of Semiconductors, Chinese Academy of Sciences 1 , Beijing 100083,

K

Kehan Jiang

Laboratory of Solid State Optoelectronics Information Technology, Institute of Semiconductors, Chinese Academy of Sciences 1 , Beijing 100083,

H

Hongyu Chai

Laboratory of Solid State Optoelectronics Information Technology, Institute of Semiconductors, Chinese Academy of Sciences 1 , Beijing 100083,

X

Xiaoguang Yang

T

Tao Yang