Photothermal Effect Induced Negative Photoconductivity and High Responsivity in Flexible Black Phosphorus Transistors
Autor: | Le Cai, Weida Hu, Qing Li, Lixin Dong, Bo Song, Chuan Wang, Suoming Zhang, Jinshui Miao |
---|---|
Rok vydání: | 2017 |
Předmět: |
Photocurrent
Electron mobility Materials science business.industry Photoconductivity Photothermal effect General Engineering General Physics and Astronomy Photodetector 02 engineering and technology Photothermal therapy 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Responsivity Thermal conductivity Optoelectronics General Materials Science 0210 nano-technology business |
Zdroj: | ACS Nano. 11:6048-6056 |
ISSN: | 1936-086X 1936-0851 |
DOI: | 10.1021/acsnano.7b01999 |
Popis: | This paper reports negative photoconductivity mechanism in flexible black phosphorus (BP) transistors built on freestanding polyimide film. Near-infrared laser (λ = 830 nm) excitation leads to significantly suppressed device on-state current with a very high responsivity of up to 53 A/W. The underlying mechanism of the negative photoconductivity is attributed to the strong photothermal effect induced by the low thermal conductivity of the polyimide substrate used. The heat generated by the infrared light illumination results in enhanced phonon scattering, reduced carrier mobility, and consequently negative photocurrent. Such a phenomenon was not observed in similar BP devices built on SiO2/Si substrates whose thermal conductivity is much higher. The above photothermal mechanism is also supported by temperature-dependent electrical characterization and device simulation. Such a flexible BP infrared photodetector with ultrahigh responsivity may find potential applications in future wearable and biointegrate... |
Databáze: | OpenAIRE |
Externí odkaz: |