TY - JOUR

T1 - Structural, electrical and gas-sensitive properties of Cr2O3 thin films

AU - Almaev, Aleksei V.

AU - Kushnarev, Bogdan O.

AU - Chernikov, Evgeny V.

AU - Novikov, Vadim A.

AU - Korusenko, Petr. M.

AU - Nesov, Sergey N.

PY - 2021/3

Y1 - 2021/3

N2 - Cr2O3 thin films were synthesized by RF magnetron sputtering of a Cr target in an oxygen-argon plasma. The effect of annealing temperature on the structural, electrical, and gas-sensitive properties of the Cr2O3 thin films was studied. According to AFM, SEM, XRD, EDX, XPS, optical spectroscopy and electrical measurements the annealed films were characterized by a polycrystalline structure, high stoichiometry, p-type conductivity and a band gap energy of 3.3 ± 0.2 eV. An increase in the annealing temperature from 350 to 450 °C leads to formation of Cr2O3 grains with a diameter from 30 to 130 nm and to a significant increase in the film electrical resistance. Cr2O3 demonstrated sensitivity to NO2, H2, NH3, vapors of acetone and toluene in the heating temperature range of 25–200 °C. Changing the annealing temperature allows to control the sensitivity of the films to certain gases. Thus, Cr2O3 thin films subjected to annealing at a temperature of 450 °C were characterized by a high response to NH3, while those annealed at a temperature of 400 °C – to toluene vapors and that annealed at 350 °C – to NO2 and acetone vapors. A qualitative model of the sensory effect was proposed.

AB - Cr2O3 thin films were synthesized by RF magnetron sputtering of a Cr target in an oxygen-argon plasma. The effect of annealing temperature on the structural, electrical, and gas-sensitive properties of the Cr2O3 thin films was studied. According to AFM, SEM, XRD, EDX, XPS, optical spectroscopy and electrical measurements the annealed films were characterized by a polycrystalline structure, high stoichiometry, p-type conductivity and a band gap energy of 3.3 ± 0.2 eV. An increase in the annealing temperature from 350 to 450 °C leads to formation of Cr2O3 grains with a diameter from 30 to 130 nm and to a significant increase in the film electrical resistance. Cr2O3 demonstrated sensitivity to NO2, H2, NH3, vapors of acetone and toluene in the heating temperature range of 25–200 °C. Changing the annealing temperature allows to control the sensitivity of the films to certain gases. Thus, Cr2O3 thin films subjected to annealing at a temperature of 450 °C were characterized by a high response to NH3, while those annealed at a temperature of 400 °C – to toluene vapors and that annealed at 350 °C – to NO2 and acetone vapors. A qualitative model of the sensory effect was proposed.

KW - Chromium oxide

KW - Thin films

KW - Magnetron sputtering

KW - Gas sensors

UR - http://www.scopus.com/inward/record.url?scp=85100676547&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/0bbee4f4-d42e-3f8a-999a-eeee0242053c/

U2 - 10.1016/j.spmi.2021.106835

DO - 10.1016/j.spmi.2021.106835

M3 - Article

VL - 151

JO - Micro and Nanostructures

JF - Micro and Nanostructures

SN - 2773-0131

M1 - 106835

ER -