Effect of substrate and thickness on the photoconductivity of nanoparticle titanium dioxide thin film vacuum ultraviolet photoconductive detector

0556005 - FZÚ 2023 RIV CH eng J - Journal Article
Cadatal-Raduban, M. - Kato, T. - Horiuchi, Y. - Olejníček, Jiří - Kohout, Michal - Yamanoi, K. - Ono, S.
Effect of substrate and thickness on the photoconductivity of nanoparticle titanium dioxide thin film vacuum ultraviolet photoconductive detector.
Nanomaterials. Roč. 12, č. 1 (2022), č. článku 10. E-ISSN 2079-4991
R&D Projects: GA MPO FV20580
Institutional support: RVO:68378271
Keywords : nanoparticle * thin film * titanium dioxide * wide band gap * semiconductor * vacuum ultraviolet * photoconductive detector
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 5.3, year: 2022
Method of publishing: Open access

Vacuum ultraviolet radiation (VUV, from 100 nm to 200 nm wavelength) is indispensable in many applications, but its detection is still challenging. We report the development of a VUV photoconductive detector, based on titanium dioxide (TiO2) nanoparticle thin films. The effect of crystallinity, optical quality, and crystallite size due to film thickness (80 nm, 500 nm, 1000 nm) and type of substrate (silicon Si, quartz SiO2, soda-lime glass SLG) was investigated to explore ways of enhancing the photoconductivity of the detector. The TiO2 film deposited on SiO2 substrate with a film thickness of 80 nm exhibited the best photoconductivity, with a photocurrent of 5.35 milli-Amperes and a photosensitivity of 99.99% for a bias voltage of 70 V. The wavelength response of the detector can be adjusted by changing the thickness of the film as the cut-off shifts to a longer wavelength, as the film becomes thicker. The response time of the TiO2 detector is about 5.8 μs and is comparable to the 5.4 μs response time of a diamond UV sensor. The development of the TiO2 nanoparticle thin film detector is expected to contribute to the enhancement of the use of VUV radiation in an increasing number of important technological and scientific applications.
Permanent Link: http://hdl.handle.net/11104/0330370