Abstract
Photodetection based on active materials such as VO2is less complex and less expensive. Usually such a detector's performance depends on the properties of active materials like the absorption coefficient, structural morphology and band gap width. Herein, we report the photoresponse of high quality VO2thin films synthesized by a single-step chemical vapor deposition. The phase was identified by X-ray diffraction and confirmed by Raman spectroscopic studies. Morphological studies by atomic force microscopy and scanning electron microscopy revealed uniform well packed grains in the thin films with a surface roughness of 54 ± 0.9 nm. Temperature variableI-Vanalysis of the thin films exhibited a first order transition with changes in resistance of 3 orders of magnitude and a temperature coefficient of resistance of −1.25% K−1at 30 °C. The infrared photodetector fabricated with synthesized VO2thin films showed good photoresponse properties with excellent stability and reproducibility at room temperature giving responsivity, sensitivity, quantum efficiency and detectivity of 7.13 × 10−2mA W−1, 1272.7%, 5.71 × 10−3% and 1.06 × 1011Jones respectively after exposing the films to a 1550 nm laser at a power density of 250 mW cm−2and 10 V bias. We also demonstrated a field assisted thermally induced phase transition by out of plane electrical and piezoforce microscopy measurements on the films.
Original language | English |
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Pages (from-to) | 12543-12550 |
Number of pages | 8 |
Journal | Journal of Materials Chemistry C |
Volume | 8 |
Issue number | 36 |
DOIs | |
State | Published - 28 Sep 2020 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© The Royal Society of Chemistry 2020.
Funding
The authors acknowledge the Micro and Nano Characterization Facility (MNCF) at Centre for Nano Science and Engineering (CeNSE), Indian Institute of Science (IISc), Bengaluru, for availing characterization facilities. Inyalot Jude Tadeo thanks IISc through the Office of International Relations (OIR) for providing him PhD scholarship.
Funders | Funder number |
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Centre for Nano Science and Engineering | |
Office of International Relations | |
Indian Institute of Science |