Title :
Sensing Properties of Tellurium Based Thin Films to Oxygen, Nitrogen and Water Vapour
Author :
Tsiulyanu, D. ; Stratan, I. ; Tsiulyanu, A. ; Eisele, I.
Author_Institution :
Dept. of Phys., Tech. Univ., Chisinau
Abstract :
Effect of O2, N2 and H20 to electrical behaviour of tellurium-based films has been studied at temperatures between 20 degC and 70 degC. The increase of oxygen partial pressure in N O2+ O2 carrier gas results in a nearly linear decreasing of the film resistance. The complete impulsive substitution of nitrogen by oxygen decreases the resistance of the film with ~6 % in 1.5 hours. The effect of humidity is more perceptible. At room temperature the resistance of the films increase with 15 % at 58%RH, but humidity has a negligible effect at temperatures higher than 50degC. The results suggest that effect of water vapour is due to simple physical adsorption, whereas effect of oxygen and nitrogen is the consequence of "week" chemisorption of these molecules on the film surface
Keywords :
adsorption; chemisorption; electrical conductivity; gas sensors; surface chemistry; tellurium; thin film sensors; 1.5 hrs; 20 to 70 C; carrier gas; chemisorption; electrical behaviour; film resistance; film surface; humidity effect; nitrogen; oxygen; physical adsorption; sensing properties; tellurium based thin films; water vapour; Gas detectors; Gases; Nitrogen; Oxygen; Physics; Surface morphology; Tellurium; Temperature sensors; Transistors; Water;
Conference_Titel :
International Semiconductor Conference, 2006
Conference_Location :
Sinaia
Print_ISBN :
1-4244-0109-7
DOI :
10.1109/SMICND.2006.283999
