Authors: M.H. Aslan, E. Menşur, E. Başaran, A.Y. Oral
573
Authors: Md. Mosharaf Hossain Bhuiyan, Tsuyoshi Ueda, Tomoaki Ikegami
Abstract: SnO2 thin films have been grown on Si3N4 substrates and also on Al2O3 sensor substrates
with Pt interdigitated electrodes by the pulsed excimer laser deposition (PLD). Palladium doped
SnO2 thin film was also prepared by the PLD method combined with the DC sputtering process.
The substrate temperature and the oxygen gas pressure were changed from 300 to 500°C and from
100 to 300 mTorr, respectively during deposition. The morphology and structural properties of the
prepared thin films have been studied by AFM and XRD. The gas sensing properties of the SnO2
sensor to NO gas was evaluated by measuring electrical resistance between interdigitated electrodes.
The highest sensitivity of the undoped SnO2 and Pd doped sensor was found to be around 9.5 and
42, respectively.
223
Authors: Mei Ping Jiang, Meng Zhao, Jin Hua Li
Abstract: Using vanadyl acetylacetonate (C10H14O5V) as precursor, use Tantalum Ethoxide (Ta(OC2H5)5) and Tetrabutyl titanate （C16H36O4Ti）as doper, by sol-gel method fabricate Ta, Ti mono doping and Ta-Ti co-doped V1-x-yTaxTiyO2 thin film. XRD spectrum indicated that the film was oriented in (011) direction. XPS results indicated the valence state of V, Ta, Ti in the film is +4, at all. While Ta mono doping, single 1at.%Ta can deduce the phase transiton temperature (Tt) by 7.8°C, phase transition hysteresis (ΔT) by 1°C. When the doping rate is 6at.%, Tt=22°C, ΔT=1°C. Ti dopings has little affection to Tt but deduce ΔT obviously. Ta-Ti co-doped V0.93Ta0.06Ti0.01O2 film thin films without phase transition hysteresis were also fabricated, and its TCR is as high as -7.58%/K at 25°C.
2177
Authors: Affa Rozana Abdul Rashid, P. Susthitha Menon, S. Shaari
Abstract: Mn doped ZnO films with different doping concentration were synthesized by sol gel method using the spin coating technique. Zn1-xMnxO thin films are prepared using 2-methoxyethanol solution of zinc acetate dehydrate and manganese acetate tetrahydrate. The quantity of Mn in the sol was synthesized with undoped ZnO, 2%, 4%, 6% and 8 % of Mn doped ZnO with an annealing temperature of 500°C. The FESEM images showed many spherical shaped nanoparticles on the cross-sectional of the films. The optical properties were characterized using UV-Vis where the transmittance and band gap value were affected by certain amount of Mn concentration. These films achieve tunable band gap characteristics by means of changing the dopant concentration. It shows an initial decrease of band gap for small concentrations of Mn, followed by an increase at higher Mn doping concentrations.
731
Authors: M. Rajendraprasad Reddy, Mutsumi Sugiyama, K. T. Ramakrishna Reddy
Abstract: Nickel-doped ZnO thin films with different Ni contents (0 - 15%) were deposited on glass substrate at 350°C by a spray pyrolysis technique. 0.1 M solutions of zinc acetate and nickel sulphate were used as the precursors with air as the carrier gas. The effect of Ni-doping on the structural and optical properties of the layers was evaluated using appropriate techniques. The X-ray diffraction studies revealed that nickel atoms were successively incorporated into ZnO host matrix without forming any detectable secondary phase. All the grown films were polycrystalline with the (002) plane as the preferred orientation and the peak position shifted towards higher diffraction angle with the increase of doping content in the films. The films had hexagonal shaped grains and the evaluated grain size varied in the range of 20 - 48 nm. The optical studies revealed a decrease of transmittance with the increase of Ni-doping content in the films and the evaluated energy band gap was found to be direct that decreased from 3.32 eV to 3.05 eV.
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