Gas sensor based on sputtered NiO thin films

The nickel oxide (NiO) thin films were deposited by dc reactive magnetron sputtering from Ni target. Investigation of surface NiO was carried out by AFM measurements. NiO films are smooth and have an average roughness of 1.04 nm and 0.69 nm for 100 nm and 50 nm thickness of NiO film, respectively. Measured NiO films demonstrate to detect low concentration H2 at temperature 250
^°
C. It was observed the improvement detection characteristics for thinner 50 nm NiO films in all investigated concentration H
2
and operational temperature.