Selective Intermixing of InGaAs/GaAs Quantum Dot Infrared Photodetectors

Date

2011

Authors

McKerracher, Ian
Wong-Leung, Jennifer
Jolley, Greg
Fu, Lan
Jagadish, Chennupati
Tan, Hark Hoe

Journal Title

Journal ISSN

Volume Title

Publisher

Institute of Electrical and Electronics Engineers (IEEE Inc)

Abstract

Quantum dot infrared photodetectors have generated significant interest in recent years. They have the potential to outperform quantum well detectors in terms of normal-incidence responsivity and higher operating temperatures. Here, an InGaAs/GaAs dots-in-a-well detector grown by metal-organic chemical vapor deposition is spectrally tuned by rapid thermal annealing under dielectric layers. Four films are considered: SiO2 deposited by both plasma-enhanced chemical vapor deposition and sputter deposition, as well as TiO2 deposited by electron-beam evaporation and sputter deposition. The devices fabricated after these treatments are compared with an uncapped but annealed reference, and also with an as-grown device. The photoresponse peak in the latter occurs at 7.1 μm, whereas the peak responses of the annealed devices range from 7.4 to 11.0 μm. The films themselves were characterized and their properties related to the photoluminescence and spectral photoresponse of each detector. Peak responsivity, specific detectivity, and dark current were also measured for each device to compare their performance.

Description

Keywords

Keywords: As-grown; Dielectric layer; Dots in a wells; Electron beam evaporation; impurity-free vacancy disordering; InGaAs/GaAs; intermixing; Metalorganic chemical vapor deposition; Operating temperature; Peak response; Peak responsivity; Photoresponses; Quantum d Annealing; impurity-free vacancy disordering; intermixing; quantum dot infrared photodetectors; spectral tuning

Citation

Source

IEEE Journal of Quantum Electronics

Type

Journal article

Book Title

Entity type

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Restricted until

2037-12-31