Correlation between Gas Sensing Properties and Preferential Orientations of Sputtered Tin Oxide Films

Abstract

Investigations on preferential orientation of tin oxide films were carried out under various conditions of film fabrication from the view point of the effect on sensing mechanism. The preferential orientation of (110) crystallographic plane resulted in the increase of sensitivity for H₂ gas. The observed relationship between the sensitivity and preferential orientation has been understood by considering the maximum atomic density on the (110) plane, which ensures the large numbers of adsorption sites for atomospheric gas as well as of direct reaction sites for H₂ gas.