@article {6791,
	title = {Highly sensitive, ultra-low dark current, self-powered solar-blind ultraviolet photodetector based on ZnO thin-film with an engineered rear metallic layer},
	journal = {Materials Science in Semiconductor Processing },
	volume = {110},
	year = {2020},
	abstract = {
	In this paper, novel self-powered, solar-blind\&nbsp;UV\&nbsp;photodetector\&nbsp;(PD) designs based on a\&nbsp;ZnO\&nbsp;thin-film with engineered back metal layer (BML) were fabricated by\&nbsp;RF\&nbsp;magnetron sputtering\&nbsp;and e-beam evaporation techniques. An exhaustive study concerning the impact of dissimilar\&nbsp;BML\&nbsp;(Au\&nbsp;and\&nbsp;Ni) on the device structural, optical and electrical properties was carried out. The measured\&nbsp;I{\textendash}V\&nbsp;curves illustrated an asymmetrical behavior, enabling a clear and distinctive\&nbsp;photovoltaic\&nbsp;mode. Superb sensitivity of\&nbsp;107,\&nbsp;high\&nbsp;ION/IOFF\&nbsp;ratio of 149dB, ultralow dark-noise current less than\&nbsp;11pA\&nbsp;and\&nbsp;responsivity\&nbsp;exceeding\&nbsp;0.27A/W were reached for the prepared\&nbsp;ZnO-based\&nbsp;UV-PDs\&nbsp;in self-powered mode. The role of the engineered\&nbsp;BML\&nbsp;in promoting effective separation and transfer of the photo-induced carriers was discussed using the band-diagram theory. The influence of the\&nbsp;annealing process\&nbsp;on the\&nbsp;UV-sensor performance was also investigated. The annealed device at\&nbsp;500{\textdegree}C\&nbsp;demonstrated a lower dark current of a few picoamperes and a high rejection ratio of\&nbsp;2.2{\texttimes}103,\&nbsp;emphasizing its exciting visible blindness characteristics.\&nbsp;Therefore, the use of an engineered\&nbsp;BML\&nbsp;with optimized annealing conditions open up new perspectives to realizing high-performance, self-powered solar-blind\&nbsp;UV-PDs\&nbsp;based on simple thin-film-ZnO\&nbsp;structure strongly desirable for various optoelectronic applications.




},
	url = {https://www.sciencedirect.com/science/article/abs/pii/S136980011932164X},
	author = {Hichem Ferhati and Fay{\c c}al Djeffal and Benhaya, Abdelhamid and Martin, N}
}
