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SrZrO3 thin films were deposited on Pt/Ti/SiO2/Si and Pt/TiO2/SiO2/Si substrates by the metal-organic decomposition technology followed by post-annealing at different temperatures ranging from 550 to 800 °C in flowing oxygen atmosphere. The microstructure characteristics of these films were investigated using X-ray diffraction, Fourier transform infrared reflectivity spectroscopy and scanning electron microscopy. Their dielectric and leakage current characteristics were evaluated by a HP-4284A precision LCR meter and a HP-4155B semiconductor parameter analyzer, respectively. The phase transformation and crystallinity results indicate that the film has amorphous structure with carbonate existing when annealed at 550 °C; however when annealed at 600 °C and above, the carbonate is decomposed and those films crystallize into the Perovskite phase. The dielectric constant of SrZrO3 is above 22 with little dispersion in a frequency range from 100 Hz to 1 MHz. The results also indicate that when annealed above 650 °C, the films using Pt/TiO2/SiO2/Si show much better leakage properties compared with those using Pt/Ti/SiO2/Si. And even annealed at 800 °C, the films deposited on Pt/TiO2/SiO2/Si substrate still have good leakage properties. [Copyright &y& Elsevier]

A low temperature nano-structured Strontium Titanate (SrTiO3) thick film oxygen gas sensors were obtained by high-energy ball milling technique and thick-film screen-printing technique. SrTiO3 nano-sized powders of around 20 nm were produced from commercial SrTiO3 and synthesized SrTiO3. The material micro-structural properties and sensor oxygen sensing properties were characterized using X-ray diffraction (XRD) and gas sensing measurements respectively. Experimental results show that the sensing property of the synthesized SrTiO3 sensors with an annealing temperature of 400 °C is much better than the commercial SrTiO3 sensors (both milled and not milled materials). Especially, their optimal operating temperature of around 40 °C is the lowest reported value for such metal oxide semiconductor gas sensors ever achieved. [Copyright &y& Elsevier]

Perovskite CaZrO3 oxide thin films were prepared by the sol–gel wet chemical technology to explore the possibility of CaZrO3 to be used as a gate material for MOSFET application. Calcium acetate, Ca(CH3COO)2 and zirconium acetylacetone, [CH3COCH&z.dbnd6;C(O&z.sbnd;)CH3]4Zr were chosen as precursors, diluted in acetic acid CH3COOH, then mixed and stirred to get the clear and transparent solution with desired ratio of Ca:Zr = 1:1. The spin-coating technique was then used to deposit perovskite CaZrO3 oxide thin films on Pt/Ti/SiO2/Si substrates, the wet films were then pyrolyzed and annealed at different temperatures under O2 atmosphere. These thin films were systematically characterized using differential thermal analysis (DTA), thermogravimetric analysis (TGA), infrared spectra (IR), X-ray diffraction (XRD), and electrical and dielectric measurements. The high dielectric constant, low leakage current density, and high breakdown strength suggest that CaZrO3 thin films can be used in high-k applications. [Copyright &y& Elsevier]