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

Pure and Sn-doped alpha -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 alpha -Fe2O3 phase was most stable in the deposition temperature range from 80 to 120 degreesC and exhibited a relatively high sensitivity to i-C4H10 and CO. On the other hand, alpha -F e2O3 thin film was almost insensitive to CH4 regardless of heat treatment a nd gas concentration. This paper describes the fabrication procedure and it s sensing characteristics are presented. Particularly, the sensing characte ristics of pure alpha -Fe2O3 and Sn doped alpha -Fe2O3 have been compared. (C) 2001 Elsevier Science B.V. All rights reserved.