We present a hydrogen sensor using mesoporous TiO2 film on silicon and its H2 sensing properties at different conditions. The sensor was formed by anodizing a sputtered Ti layer on silicon and having it annealed for crystallization. The material and electrical characterization included a study of morphology (FESEM), elemental composition (EDS), crystalline structure (XRD) and current-voltage behavior (semiconductor parameter analyzer). The sensor with Pt electrodes showed promising hydrogen sensing properties in air, such as good response to low hydrogen concentration (20-1000 ppm), fast response time of 5 s and recovery time of 125 s at 1000 ppm. The sensor response is shown to be independent toward relative humidity in the testing atmosphere.
- Gas sensor