HUMIDITY SENSOR USING CuO NANORICES THIN FILM

Abstract

In this paper, a humidity sensor based on CuO has been successfully fabricated. Thin-film of CuO nanorices were synthesized by Successive Ionic Layer Adsorption and Reaction (SILAR) method on silicon wafer with Si3N4thinlayer as a substrate. The microstructure and morphology of the samples were investigated using X-ray diffraction(XRD) and scanning electron microscopy (SEM). Humidity sensing properties of the thin films have been studied. The sensing response has been measured in the relative humidity (RH) range from 20 up to 80 % at room temperature. It was found that impedance of the system decreases as the RH was increased. The prepared sensor revealed good reversibility with response and recovery time of 130 s and 320 s respectively. The complex impedance spectra were analyzed in the range of 0.1 to 1 kHz. This type of humidity sensor can be used as a new generation of ecological sensors with low cost and good stability. It makes the sensor a candidate for practical applications.

Research Report on the Application of MEMS Sensors Based on Copper Oxide Nanofibers in the Braking of Autonomous Vehicles

“…Copper oxide is a typical chemical resistance sensing material, and its sensing mechanism is inseparable from the change in the conductivity of the material itself caused by the adsorption of water molecules on the surface [ 13 ]. As shown in Figure 1 , the adsorption of water molecules on the surface of copper oxide can be divided into physical adsorption and chemical adsorption [ 14 ]. Charge transfer is achieved by proton hopping between hydroxyl groups of the chemisorption layer [ 4 ].…”

Research Progress on Humidity-Sensing Properties of Cu-Based Humidity Sensors: A Review

“…Although many articles have reported improving the sensitivity and response speed of copper oxide-based humidity sensors to a certain extent so far, this has not fully met the needs of the work. Perillo et al [54] synthesized copper oxide nanofilms on silicon wafers by the continuous ionic layer adsorption reaction method (SILAR), and the fabricated sensors exhibited good response and recovery time at room temperature. Hsu et al [55] synthesized high-density CuO/Cu 2 O composite nanowires by heating oxidation method, which effectively improved the sensitivity of the sensor to humidity.…”