Solution Processed Hybrid Polymer: HgTe Quantum Dot Phototransistor with High Sensitivity and Fast Infrared Response up to 2400 nm at Room Temperature

Advanced Science

Mengyu Chen¹  Guodong Zhou¹  Ni Zhao¹  Ning Ke¹  Qiang Zhu¹  Ching Ping Wong¹  Wai Kin Yiu²  Stephen V. Kershaw²  Andrey L. Rogach²  Yifan Dong³ 

[1] Department of Electronic Engineering The Chinese University of Hong Kong Shatin, New Territories, 999077 Hong Kong SAR China;Department of Materials Science and Engineering and Centre for Functional Photonics (CFP) City University of Hong Kong Kowloon Hong Kong SAR 999077 China;Engineering Research Center of Nano‐Geomaterials of Ministry of Education Faculty of Materials Science and Chemistry China University of Geosciences Wuhan 430074 China;

关键词: HgTe quantum dots;    infrared photodetection;    IR photodetection;    phototransistors;    poly(3‐hexylthiophene);   

DOI  :  10.1002/advs.202000068

来源: DOAJ

【 摘 要 】

Abstract Narrow bandgap semiconductor‐based photodetectors often suffer from high room‐temperature noise and are therefore operated at low temperatures. Here, a hybrid poly(3‐hexylthiophene) (P3HT): HgTe quantum dot (QD) phototransistor is reported, which exhibits high sensitivity and fast photodetection up to 2400 nm wavelength range at room temperature. The active layer of the phototransistor consists of HgTe QDs well dispersed in a P3HT matrix. Fourier‐transform infrared spectra confirm that chemical grafting between P3HT and HgTe QDs is realized after undergoing prolonged coblend stirring and a ligand exchange process. Thanks to the shifting of the charge transport into the P3HT and the partial passivation of the surface traps of HgTe QDs in the blend, the P3HT: HgTe QD hybrid phototransistor shows significantly improved gate‐voltage tuning, 15 times faster response, and ≈80% reduction in the noise level compared to a pristine HgTe QD control device. More than 1011 Jones specific detectivity (estimated from the noise spectral density measured at 1 kHz) is achieved at room temperature, and the response time (measured at 22 mW cm−2 illumination intensity) of the device is less than 1.5 µs. That is comparable to commercial epitaxially grown IR photodetectors operated in the same wavelength range.

【 授权许可】

Unknown