Fabrication and gas sensing properties of α-Fe2O3 thin film prepared by plasma enhanced chemical vapor deposition (PECVD)

Pure and Sn-doped α-Fe2O3 thin films were deposited on Al2O3 substrate by plasma enhanced chemical vapor deposition (PECVD) process using Fe(CO)5 and SnCl4 as a source materials. The α-Fe2O3 phase was most stable in the deposition temperature range from 80 to 120°C and exhibited a relatively high sensitivity to i-C4H10 and CO. On the other hand, α-Fe2O3 thin film was almost insensitive to CH4 regardless of heat treatment and gas concentration. This paper describes the fabrication procedure and its sensing characteristics are presented. Particularly, the sensing characteristics of pure α-Fe2O3 and Sn doped α-Fe2O3 have been compared.