Undoped and Cobalt Doped ZnO Thin Films Ethanol Gas Sensors

Salah Hazaa, Manar Th, Najiba Mansor, Al-Hamadani
International Journal of Latest Research in Engineering and Technology   unpublished
In this research, undoped ZnO and doped with cobalt ZnO:Co thin films with different weight percentages of (1, 3, 5,7)% have been prepared on pre-heated glass substrates up to (400℃) with average thickens (300nm) by using Atmospheric Pressure Chemical Vapor Deposition (APCVD) technique. The effect of Co-doping on structural properties and the ethanol vapor gas sensing has been investigated. The results of XRD showed that the all deposited films are polycrystalline hexagonal structure with a
more » ... tructure with a preferred orientation in the (002) direction, the doping with Co does not change crystal structure of ZnO. The increase in the dopant concentration into the ZnO leads to an increase of the crystallite size of the films which is well known causes to increase the gas sensitivity. The effect of operating temperature on performance of the sensor material has been investigated and a choice of optimum temperature was made at around 300 °C.