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Title: GaAs/GaAsSb Core–Shell Configured Nanowire-Based Avalanche Photodiodes up to 1.3 μm Light Detection
We report the first study on a GaAs/GaAsSb core−shell (CS)-configured nanowire (NW)-based separate absorption, charge control, and multiplication region avalanche photodiode (APD) operating in the near-infrared (NIR) region. Heterostructure NWs consisted of GaAs and tunable band gap GaAs1−xSbx serving as the multiplication and absorption layers, respectively. A doping compensation of absorber material to boost material absorption, segment-wise annealing to suppress trap-assisted tunneling, and an intrinsic i-type and n-type combination of the hybrid axial core to suppress axial electric field are successfully adopted in this work to realize a room-temperature (RT) avalanche photodetection extending up to 1.3 μm. In an APD device operating at RT with a unity-gain responsivity of 0.2−0.25 A/W at ∼5 V, the peak gain of 160 @ 1064 nm and 18 V reverse bias, gain >50 @ 1.3 μm, are demonstrated. Thus, this work provides a foundation and prospects for exploiting greater freedom in NW photodiode design using hybrid axial and CS heterostructures.  more » « less
Award ID(s):
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
ACS Publications
Date Published:
Journal Name:
ACS Applied Nano Materials
Page Range / eLocation ID:
5093 to 5105
Subject(s) / Keyword(s):
["core−shell nanowires, avalanche photodiodes, SAM-APD, GaAsSb, hybrid axial\/CS NWs, near-infrared, photodetector,\nnon-selective growth, ensemble nanowires, self-catalyzed, VLS\/VS growth"]
Medium: X
Sponsoring Org:
National Science Foundation
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