P1.0.20 N-P Transition Sensing Response of Strontium Titanate Ferrite Sol-Gel Thin Films
- Event
- 14th International Meeting on Chemical Sensors - IMCS 2012
2012-05-20 - 2012-05-23
Nürnberg/Nuremberg, Germany - Chapter
- P1.0 Metal Oxide-based Sensors
- Author(s)
- C. Chow, O. Tan, M. Tse - School of Electrical and Electronic Engineering, Nanyang Technological University
- Pages
- 806 - 809
- DOI
- 10.5162/IMCS2012/P1.0.20
- ISBN
- 978-3-9813484-2-2
- Price
- free
Abstract
Perovskite oxide has been reported as a potential gas sensing material in addition to commonly used binary oxide. Strontium titanate ferrite (SrTi0.6Fe0.4O3) thin film sensors were fabricated using modified sol-gel spin coating technique and annealed at different annealing temperatures. An anomalous n- to p-type transition of oxygen sensing response was observed as annealing temperature increased. A typical p-type sensing response was observed for sensors annealed at temperature of 500 °C and higher. On the other hand, sensors annealed below 450 °C showed an unusual n-type sensing response, which has never been reported. The n-type sensing response was caused by the amorphous phases in the thin film annealed at low annealing temperature, as revealed by X-ray diffraction (XRD), tunneling electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS).