TY - JOUR

T1 - Mercury Telluride Quantum Dot Based Phototransistor Enabling High Sensitivity Room Temperature Photodetection at 2000 Nanometers

AU - Chen, Mengyu

AU - Lu, Haipeng

AU - Abdelazim, Nema Mohamed Safwat Ibrahim

AU - Zhu, Ye

AU - Wang, Zhen

AU - Ren, Wei

AU - Kershaw, Stephen V.

AU - Rogach, Andrey L.

AU - Zhao, Ni

PY - 2017/6/27

Y1 - 2017/6/27

N2 - 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 × 1010 cm Hz1/2 W–1 (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.

AB - 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 × 1010 cm Hz1/2 W–1 (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.

KW - gas sensing

KW - near-to-mid infrared

KW - photodetection

KW - phototransistor

KW - quantum dot

U2 - 10.1021/acsnano.7b00972

DO - 10.1021/acsnano.7b00972

M3 - Journal article

VL - 11

SP - 5614

EP - 5622

JO - ACS Nano

JF - ACS Nano

SN - 1936-0851

IS - 6

ER -