Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7133732 | Sensors and Actuators A: Physical | 2018 | 9 Pages |
Abstract
2-Dimensional (2D) wide band-gap semiconductor molybdenum disulfide (MoS2) nanosheets as an ultraviolet (UV) photo-conductive material were used in surface acoustic wave (SAW) resonators for UV light sensing. A SAW resonator based on zinc oxide (ZnO) piezoelectric film deposited on glass through radio frequency (RF) magnetron sputtering technique was prepared, in which the sub-microscale gold/chromium (Au/Cr) interdigital transducers (IDTs) and grating reflectors were fabricated onto the ZnO surfaces using the electron beam lithography and lift-off techniques to form the IDTs/ZnO/glass-based SAW resonator with a working frequency at â¼1.02Â GHz. The MoS2 nanosheets prepared by electrochemical lithiation process were coated on IDTs region to form a highly sensitive SAW UV sensor, exhibiting an interesting photoresponse behavior to UV radiation. A maximum frequency shift of â¼3.5Â MHz was found under 365Â nm UV radiation with power intensity of 1.466Â mW/cm2, which is attributed to the high resonant frequency (in GHz) and high specific surface area of photo-conductive MoS2 nanosheets. It is suggested that the adsorption and desorption of oxygen on MoS2 nanosheets play the dominant roles in the frequency-upshift due to mass loading effect and acoustoelectric effect, meanwhile, acoustoelectric effect also creates the SAW attenuation.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Peng Zhou, Changsong Chen, Xiang Wang, Baofa Hu, Haisheng San,