Title :
InGaAs-Capped InAs–GaAs Quantum-Dot Infrared Photodetectors Operating in the Long-Wavelength Infrared Range
Author :
Lin, Wei-Hsun ; Tseng, Chi-Che ; Chao, Kuang-Ping ; Mai, Shu-Cheng ; Lin, Shih-Yen ; Wu, Meng-Chyi
Author_Institution :
Inst. of Electron. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan
Abstract :
A ten-period InAs-GaAs quantum-dot infrared photodetector (QDIP) with 8-nm In0.15Ga0.85 As capping layer grown after quantum-dot (QD) deposition is investigated. With reduced InAs QD coverage down to 2.0 mono-layers, responses at 10.4 and 8.4 mum are observed for the device under positive and negative biases, respectively. The phenomenon is attributed to the large Stark effect resulted from the asymmetric band diagrams of the device under different voltage polarities. The demonstration of long-wavelength infrared detections with the simple structures of the InGaAs-capped QDIP is advantageous for the development of multicolor QDIP focal-plane arrays.
Keywords :
III-V semiconductors; Stark effect; focal planes; gallium arsenide; indium compounds; infrared detectors; photodetectors; semiconductor quantum dots; In0.15Ga0.85As-InAs-GaAs; Stark effect; asymmetric band diagrams; capping layer; long-wavelength infrared detections; multicolor QDIP focal-plane arrays; quantum-dot deposition; quantum-dot infrared photodetector; size 8 nm; voltage polarity; Quantum-dot infrared photodetectors (QDIPs);
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2009.2026630
