Title :
Nanocrystalline TiO2 thin films for O2 gas sensing
Author :
Li, Y. ; Atashbar, M.Z. ; Ghantasala, M.K. ; Wlodarski, W. ; Austin, M.W.
Author_Institution :
Dept. of Commun. & Electron. Eng., RMIT Univ., Vic., Australia
Abstract :
Titanium dioxide (TiO2) thin films have been prepared using a nanosized TiO2 suspension and a spin-coating process. The morphology, microstructure, crystalline structure and chemical composition of the TiO2 thin films have been investigated using SEM, XRD, and RBS. SEM analysis showed that the films are smooth and uniform with an average particle size of 25 nm. The crystal structure of the films is a mixture of 70% anatase and 30% rutile phases. RBS characterisation has revealed that the film is sub-stoichiometric TiO2-n. The variation of electrical resistance of the thin films has been examined at different oxygen concentrations from 1 ppm to 1%. The response of the sensor to 100 ppm, 1000 ppm, and 1% O2 gas is 1.4, 2.4, and 4.9, respectively. The response and recovery times (t0.90%) are about 2 minutes
Keywords :
Rutherford backscattering; X-ray diffraction; crystal structure; electric sensing devices; gas sensors; nanostructured materials; particle size; scanning electron microscopy; semiconductor thin films; spin coating; titanium compounds; O2; O2 gas sensing; RBS; SEM; TiO2; XRD; anatase; chemical composition; crystalline structure; electrical resistance; microstructure; morphology; nanocrystalline thin films; particle size; recovery time; response time; rutile; spin-coating; Chemicals; Crystal microstructure; Crystallization; Electric resistance; Gas detectors; Morphology; Sensor phenomena and characterization; Titanium; Transistors; X-ray scattering;
Conference_Titel :
Optoelectronic and Microelectronic Materials Devices, 1998. Proceedings. 1998 Conference on
Conference_Location :
Perth, WA
Print_ISBN :
0-7803-4513-4
DOI :
10.1109/COMMAD.1998.791649
