Quantum-dot infrared photodetectors with p-type-doped GaAs barrier Layers

Author

Shu-Ting Chou ; Cheng-Hsuan Tsai ; Meng-Chyi Wu ; Lin, S.-Y. ; Chi, J.-Y.

Author_Institution

Dept. of Electr. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan

Volume

17

Issue

11

fYear

2005

Firstpage

2409

Lastpage

2411

Abstract

We investigate the effects of p-type-doping concentration in the GaAs barrier layer on the multistack InAs-GaAs quantum-dot infrared photodetectors (QDIPs). The dark current decreases with the p-type-doping density in the GaAs barrier layer. The QDIP with five stacks and a p-type-doping concentration of 1×10/sup 16/ cm/sup -3/ in the GaAs barrier layer and show an observable spectral response with a peak responsivity of 0.5 A/W at 6 μm. With increasing the p-type-doping density up to 1×10/sup 17/ cm/sup -3/, the QDIP structure shows a reduced photocurrent and a nondetectable response. The QDIPs with p-type-doped GaAs barrier layers and different stack numbers exhibit a saturation photocurrent, where the saturation voltage is proportional to the stack number.

Keywords

III-V semiconductors; dark conductivity; doping profiles; gallium arsenide; indium compounds; infrared detectors; photoconductivity; photodetectors; quantum well devices; semiconductor doping; semiconductor quantum dots; GaAs; InAs-GaAs; dark current; p-type-doped GaAs barrier layers; p-type-doping concentration; quantum-dot infrared photodetectors; responsivity; saturation photocurrent; Current measurement; Dark current; Electromagnetic wave absorption; Gallium arsenide; Infrared detectors; Photoconductivity; Photodetectors; Quantum dots; Quantum wells; Voltage; Quantum dots (QDs); quantum-dot infrared photodetector (QDIP);

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2005.858149

Filename

1522336