Analysis on Sensitivity of Semiconductor Methane Gas Sensors by Ultrasonic Process

Abstract

The thin films of Pt and Zn were coated with on the electrode in the board. Thin films of Pt are fabricated by ion plasma and Zn is manufactured by DC sputtering methods. Then the deposited boards were produced by ultrasonic chemical deposition in 0.01 M aqueous solution of C6H12N4 and Zn(NO3)2∙6H2O. To make the ZnO prepared-substrates were heat-treated at 600 °C for 1 hour and the sensitivity of ZnO-structured sensors was tested for Methane gas. In the experiment, the concentrations of Methane gas ranged from 15% to 40% LEL. We measured the change of the voltage before and after the Methane gas injections to judge whether it had a suitable performance as the Methane gas sensors. As a result of the sensitivity of the fabricated sensor, it was found that the voltage increases according to the Methane concentration. The sensitivity of the sensor constantly increased, so the graph showed a linear shape. Also, the fabricated sensors showed very short stabilization time, fast reaction and recovery. As a result, the using possibility of the detector is suggested where detection is required.