SnO2 thin films for gas sensors modified by hexamethyldisilazane after rapid thermal annealing

Simple method of SnO2 layer modification, using very small quantity of hexamethyldisilazane and rapid thermal annealing in the range 800-1200 degreesC is proposed. The distribution profile of the dopant elements of C, N, Si in the SnO2/SiO2/Si structure is investigated. Penetration of Si in the whole depth of SnO2 is revealed and formation of SiO2 regions in the SnO2 bulk is assumed. Simultaneously, Sn diffusion in the SiO2 layer is observed. The combination of standard AES and XPS techniques with a hollow cathode discharge method appears to be very useful for detection of traces of dopants in the layers. (C) 2004 Elsevier B.V. All rights reserved.