TEM INVESTIGATIONS OF Au-NiO NANOCRYSTALLINE THIN FILMS AS GAS SENSING MATERIAL

Ivan Hotový - Jozef Liday - Lothar Spiess - Henry Romanus - Mária Čaplovičová - Dalibor Búc - Helmuth Sitter - Alberta Bonanni

   Nanocrystalline NiO thin films were deposited by dc reactive magnetron sputtering in a mixture of oxygen and argon and subsequently coated by Au on a NiO film surface. Very thin Au overlayers with a thickness of about 1 and $7\,$nm have been prepared by magnetron sputtering. Then, the surface modified NiO films have been analysed by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected electron diffraction (SAED) and energy dispersive X-ray (EDX) methods. NiO thin films had a polycrystalline structure (FCC NiO phase) with the size of the nanocrystals ranging from a few nanometers to 10 nm. The electrical response of NiO-based structure, as a function of hydrogen concentration has been measured.

Keywords: thin films, nanocrystals, TEM, nickel oxide

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