Sensing Properties Of Sensors Research Articles

Effect of Gas Diffusion Process on Sensing Properties of SnO2 Thin Film Sensors in a SiO2 / SnO2 Layer‐Built Structure Fabricated by Sol‐Gel Process

The effects of coating on gas‐sensing properties of thin film sensors with interior electrodes have been investigated. The thicker the film, the higher the sensitivity of the film in the double‐layer structure. Significant enhancement in sensitivity was also achieved with the coating films having a large volume fraction of small pores. The coatings also induced a drastic slowdown of recovery speed after removal of . From these results, restricted permeation into the interior film, in comparison to diffusivity, is suggested to be responsible for the significant enhancement in sensitivity. Under the same conditions, however, enhancement in sensitivity was relatively small. Thus, it was revealed that sensing properties of sensors with interior electrodes can be modified by controlling the gas diffusion process.