Development of gas sensors on the basis of couple of nanocrystalline oxides of Ме1О-Ме2О metals creates opportunities for producing on their basis advanced materials, which meet modern requirements and have improved parameters. In such systems SnO2 attracts the most attention as main gas sensitive ma-terial. As inverter may be used oxides of metals, d-elements of chrome, molybdenum, tungsten, iron etc.
Formation of films of individual tin and iron oxides and their mixtures is carried out by oxidation pyro-lysis of tin tetraethyl and pentacarbonil or iron ethylate from gas phase in the range of temperature from 110 to 500 0C. Concretion of films had been carried out on plates from monocrystalline silicone, NaCl crystals and on glassceramic substrates. Using RHEED, TEM, AFM, AES and Mössbauer spect-roscopy methods we probe the structure and composition of the films. It had been revealed that tin and iron oxide films, formed under 3000C and 150 0C were amorphous. By increase of temperature formation of polycrystalline phase in their composition take place. In case of iron film it had been observed that by inc-rease of temperature of film formation roughness of their surfaces had been reduced. In this case, the size of amorphous globules enlarges. They become larger in size, but more flat. Research of tin oxide films had been showed that temperature of their formation influences on their primary orientation and rough-ness. It had been established that roughness of amorphous films lower than polycrystalline ones. Research of phase composition of tin and iron oxides mixture films showed that all of them may be amor-phous and (or) crystal, depending on concentration temperature, and do not contain any other mix-tures, not peculiar for individual oxides. In this work electric properties of the formed films had been also stu-died.
This work was supported by INTAS, grant №2000-0066.
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