10.1021/acsnano.7b00972.s001
Mengyu Chen
Mengyu
Chen
Haipeng Lu
Haipeng
Lu
Nema M. Abdelazim
Nema M.
Abdelazim
Ye Zhu
Ye
Zhu
Zhen Wang
Zhen
Wang
Wei Ren
Wei
Ren
Stephen V. Kershaw
Stephen V.
Kershaw
Andrey L. Rogach
Andrey L.
Rogach
Ni Zhao
Ni
Zhao
Mercury
Telluride Quantum Dot Based Phototransistor Enabling High-Sensitivity
Room-Temperature Photodetection at 2000 nm
American Chemical Society
2017
detectivity
gas-injection synthesis method
mercury Telluride Quantum Dot
HgTe QDs
detection devices
phototransistor structure
2.1 μ m
epitaxial-grown photodetectors
silicon technologies
QD photodetectors
solution processability
2000 nm Near-to-mid-infrared photodetection technologies
performance bottleneck
carbon monoxide gas
2 μ m wavelength range
room-temperature device response
quantum dot
QD phototransistor
2 kHz modulation frequency
detection technologies
photoluminescence quantum
technology
device engineering
scalable fabrication
application requirements
Phototransistor Enabling High-Sensitivity Room-Temperature Photodetection
photoluminescence peak
gas concentration
2017-05-19 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Mercury_Telluride_Quantum_Dot_Based_Phototransistor_Enabling_High-Sensitivity_Room-Temperature_Photodetection_at_2000_nm/5077849
Near-to-mid-infrared photodetection
technologies could be widely deployed to advance the infrastructures
of surveillance, environmental monitoring, and manufacturing, if the
detection devices are low-cost, in compact format, and with high performance.
For such application requirements, colloidal quantum dot (QD) based
photodetectors stand out as particularly promising due to the solution
processability and ease of integration with silicon technologies;
unfortunately, the detectivity of the QD photodetectors toward longer
wavelengths has so far been low. Here we overcome this performance
bottleneck through synergistic efforts between synthetic chemistry
and device engineering. First, we developed a fully automated aprotic
solvent, gas-injection synthesis method that allows scalable fabrication
of large sized HgTe QDs with high quality, exhibiting a record high
photoluminescence quantum yield of 17% at the photoluminescence peak
close to 2.1 μm. Second, through gating a phototransistor structure
we demonstrate room-temperature device response to reach >2 ×
10<sup>10</sup> cm Hz<sup>1/2</sup> W<sup>–1</sup> (at 2 kHz
modulation frequency) specific detectivity beyond the 2 μm wavelength
range, which is comparable to commercial epitaxial-grown photodetectors.
To demonstrate the practical application of the QD phototransistor,
we incorporated the device in a carbon monoxide gas sensing system
and demonstrated reliable measurement of gas concentration. This work
represents an important step forward in commercializing QD-based infrared
detection technologies.