The physical processes of semiconductor and heavy metals oxides sensors on H2S are investigated and possible physical mechanisms of gas sensitivity in the atmosphere of air and nitrogen are considered. Mechanism of adsorbtive-desorbtive sensitivity of heterostuctures to H 2S is connected with conductivity variation caused by the hydrogen atoms diffusion to the boundaries. duction veil known that H 2S is one of the most agressive gases which actively interacts with ent materials' surfaces and

more »

... which is to be seriously controled in ecological ns monitoring. The physico-chemical criterion for the material selection in gas rs construction is the minimal chemical compounds formation energy for sulphur lydrogen atoms. This criterion realization gives possibility to construct sensitive nts with relatively low working temperature. In accordance with the principle, thin ium chalcogenides' and heavy metals oxides' layers have the minimal chemical 5 formation energy with S and H atoms and thus, they are the most favourable for msors constructions. Besides the mentioned, the cadmium chalcogenide metalloid he similar chemical nature with sulphur atoms. High sensitivity to H 2S in the ace of S 0 2 and 0 2 of air is enough important in the practical meaning. ample manufacturing method and measurements semiconductor Films were obtained by the method of thermal evaporation in high m and by the MOC technology. Binary oxide semiconductors were obtained in the ss of sequent coating of sitall substrates by each of the components with previously ited Ohmic contacts. Electronic properties of CdS, CdSe thin films and of Zn, Cd, 1, Pb oxides obtained at different technological conditions were investigated. Gas ive parameters of such structures contacting with H 2S were investigated in the 83-908335-0-6 EUROSENSORS XI