Chemosorption hydrogen gas sensor based on MOSFET with optical activation

18th International School on Condensed Matter Physics: "Challenges of Nanoscale Science: Theory, Materials, Applications"

Stoyanova, T.V.^1 ; Tomaev, V.V.^1,3 ; Stoyanov, N.D.^2 ; Andreev, S.K.^4

Depatment of Physics, National University of Mineral Resources, V.O. 21-ya liniya, Saint-Petersburg, Russia^1

LED Microsensor NT, LLC, Politechnicheskaya 26, Saint-Petersburg, Russia^2

Depatment of Chemistry, State University, Universitetskii prosp. 26, Saint-Petersburg Petrodvoretc, Russia^3

Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., Sofia, Bulgaria^4

关键词: Adsorption centres;    Hydrogen gas sensors;    Impedance spectroscopy;    MOS-FET;    Optical activation;    Positive charges;    Real components;    Visible spectral range;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/558/1/012039/pdf
DOI  :  10.1088/1742-6596/558/1/012039

来源: IOP

【 摘 要 】

In this paper we present an approach which allows to increase the sensitivity of the sensors at room temperature. Field effect transistors with SnO2gate in combination with optical activation of the adsorption centres on the surface were utilized. Studies of photosensitivity were carried out using a set of LEDs in the visible spectral range by the method of impedance spectroscopy. Optical activation of the adsorption centres in the SnO2gate leads to the additional accumulation of positive charges on top of the gate H+. Positive charge caused broadening of the channel in MOSFET sensor, resulting to lower real component of the impedance. These results show that optical activation allows to detect significantly lower concentrations of the hydrogen contained gases.