Proceedings Article | 17 September 2018
KEYWORDS: Nanowires, Zinc oxide, Photodetectors, Transistors, Electronic components, Field effect transistors, Sensors, Light emitting diodes, Solar cells, Ultraviolet detectors
Due to the high surface to volume ratio, nanowire based components benefit from new properties typical of the nanoscale. ZnO nanowires have already proved their usefulness in the realization of multiple electronic components, such as FET transistors, gas detectors, photodetectors, LEDs or even solar cells.
ZnO nanowires have also shown themselves to be very promising UV detectors thanks to their significant photoconductive gain, as high as G =10^8 [1]. This makes them suitable for single photon detection, or at least detection of very dim light. The main current drawback is the recovery time (minimum time between 2 detections) which we develop last hours.
The device we developed is a good candidate for opto-electronic applications. Our device is a photodetector with ohmic contact and it behaves like a transistor. Our experiments stress out the importance of surface effect on the electrical by taking measurements in different atmospheres (oxygen, air, vacuum and argon). These surface states are the reason for the existence of a photoconductive gain, we obtain a maximum gain of G =6.10^6. In counterpart of this great gain, the persistence of the photocurrent (which can last up to several hours) prevents the device from operating at high frequency. We propose a method to reduce this time by applying a gate voltage.
REFERENCES
[1] C. Soci , A. Zhang, B. Xiang, S. A. Dayeh, D. P. R. Aplin, J. Park, X. Y. Bao, Y. H. Lo, and D. Wang, Nano Lett. 7, 1003 (2007).