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Iron silver oxide (AgxFe2−xO3; 0xFe2−xO3 shown in the figure can be indexed to the hexagonal structure of silver oxide and the rhombohedral structure of hematite and new X-ray Diffraction (XRD) peaks of AgxFe2−xO3 structure. The annealing and doping process seems to cause a serious change in the crystal structure of the thin film, it showed a serious change in its electrical properties. The electrical parameters of resistance for thin films were measured using the Hall measurement method at room temperature. With Hall measurements, the n-type carrier concentration of the Fe2O3 structure was calculated, and it was observed that its resistance was 1MΩ. Likewise, it was observed that AgxFe2−xO3 exhibited an n-type carrier concentration, and its resistance was calculated to be 0.5MΩ. The conductivity change is based on silver doping. The doping process seems to cause a change in the bandgap of the thin film, it showed a change in its optical properties. The film’s optical absorption was measured by UV–Vis photo spectroscopy. Subsequently, the structural and topographic properties of AgxFe2−xO3 structures were investigated by high-precision characterization devices. [ABSTRACT FROM AUTHOR]

The effects of vacuum and oxygen annealing on Sr2-xNbxIrO4 samples have been systematically investigated. The annealing under vacuum leads to an enhanced insulating state of the Sr2-xNbxIrO4 compounds, which could be due to the evaporation of oxygen atoms which breaks the superexchange interaction between Ir and O ions. The annealing under oxygen atmosphere results in substantial straightening of the in-plane Ir–O–Ir bond and rapid depression of the canted antiferromagnetic ordering state. Importantly, the insulator-to-metal transition has been achieved by oxygen annealing of the Sr2-xNbxIrO4 samples, which could be due to the enhanced hybridization of Ir 5d orbitals with the neighboring O 2p orbitals. The present results suggest that the annealing treatment could be an effective way for exploring of novel physical phenomena in Sr2IrO4 and related compounds. [ABSTRACT FROM AUTHOR]

The effects of vacuum and oxygen annealing on Sr2-xNbxIrO4 samples have been systematically investigated. The annealing under vacuum leads to an enhanced insulating state of the Sr2-xNbxIrO4 compounds, which could be due to the evaporation of oxygen atoms which breaks the superexchange interaction between Ir and O ions. The annealing under oxygen atmosphere results in substantial straightening of the in-plane Ir–O–Ir bond and rapid depression of the canted antiferromagnetic ordering state. Importantly, the insulator-to-metal transition has been achieved by oxygen annealing of the Sr2-xNbxIrO4 samples, which could be due to the enhanced hybridization of Ir 5d orbitals with the neighboring O 2p orbitals. The present results suggest that the annealing treatment could be an effective way for exploring of novel physical phenomena in Sr2IrO4 and related compounds. [ABSTRACT FROM AUTHOR]

This study explored the effects of annealing on the structural, optical, and semiconducting properties of hydrothermally derived CoS 2 nanoparticles and its impact on carrier transport through a Schottky junction ITO/CoS 2 /Al device. The current rectification ratio obtained from current–voltage measurements for CoS 2 (derived at room temperature) was 21.57 at a potential of ±1 V, but it was 70.61 for the Schottky junction fabricated by annealing (at 250 °C) with CoS 2. The ideality factor (n), series resistance (R s), barrier potential (φ b), and other parameters were determined for the devices. The ideality factor improved significantly to 1.34 for the sample, produced at 250 °C. The charge transport phenomenon was examined based on thermionic emission theory and related parameters, such as the mobility (of the order of 10−4 m2V−1s−1), carrier concentration (of the order of 1020 m−3), density of state (of the order of 1021 eV−1m−3), and transit time (of the order of 10−9s), were estimated by employing space charge limited conduction (SCLC) theory. The occurrence of free carriers gave rise to ferromagnetic behavior, which was also studied. This is the first study to investigate the relationship between the magnetic spin and electronic behavior of CoS 2 nanoparticles. The observed intrinsic ferromagnetism and magnetic behavior with respect to the temperature and magnetic field indicated the suitability of the material for spin-based electronic applications. Finally, the potential behavior of annealed (at 250 °C) CoS 2 in the ITO/CoS 2 /Al Schottky device was observed. [Display omitted] • Hydrothermal synthesis and characterizations of CoS 2 nanomaterial. • Derived CoS 2 annealed at 200 °C and 250 °C. • Successful fabrication of ITO/CoS 2 /Al Schottky device. • Annealed CoS 2 improves carrier transport behavior. • Studied magnetic behavior to check potentiality of materials in spintronic application. [ABSTRACT FROM AUTHOR]

The improvement of electrical properties by thermal annealing of Ga-doped ZnO (GZO) films deposited by sputtering has been investigated. The resistivity of a GZO film deposited at room temperature decreases as the vacuum annealing temperature is increased up to 400 °C. A further increase in annealing temperature increases the resistivity, resulting from a decrease in carrier density. On the other hand, the formation of a SiO 2 layer covering the surface of the GZO film eliminates this resistivity upturn, causing its decrease from 1.26 × 10 −3  Ω cm before annealing to 4.1 × 10 −4  Ω cm at 600 °C. A comparison between the films annealed at different vacuum pressures have revealed that electrical resistivity is improved by preventing atomic migration between the GZO lattice and the surrounding atmosphere, i.e., oxygen absorption to or Zn desorption from the GZO lattice. The optical transmittance of a SiO 2 -capped GZO film is higher than that of a bare GZO film after thermal annealing. [ABSTRACT FROM AUTHOR]

Abstract: In order to investigate the relation among the superconducting transition Tc , carrier density n, resistivity ρ and the microstructure in the polycrystalline (In2O3)1− x –(ZnO) x films, we prepared specimen films by post annealing of amorphous films with x =0.025 at various annealing temperature Ta and for annealing time ta =1h and 4h. As for microstructures, we have investigated the distribution of elements by scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS). We have found followings: (1) The annealed films clearly show the superconductivity of which Tc depends on Ta , ta and n. This indicates that the superconductivity is determined by the combination of crystallinity and carrier density. (2) The data on STEM–EELS spectra mapping of indium plasmon indicate that droplets of the pure indium phase exist inside a film, where the distribution of these droplets dispersed. Therefore, it seems that droplets do not form an electrical conducting path, that is, it is possible that observed superconductivity is due to intrinsic characteristic of polycrystalline (In2O3)1− x –(ZnO) x films. [Copyright &y& Elsevier]

Thin polycrystalline zinc-doped indium oxide (In2O3-ZnO) films were prepared by post-annealing amorphous films with various weight concentrations x of ZnO in the range 0 ⩽ × ⩽ 0.06. We have studied the dependences of the resistivity ρ and Hall coefficient on temperature T and magnetic field H in the range 0.5 ⩽ T ⩽ 300 K, H ⩽ 6 Tfor 350 nm films annealed in air. Films with 0 ⩽ × × 0.03 show the superconducting resistive transition. The transition temperature Tc is below 3.3K and the carrier density n is about 1025-1026 m-3. The annealed In2O3-ZnO films were examined by transmission electron microscopy and x-ray diffraction analysis revealing that the crystallinity of the films depends on the annealing time. We studied the upper critical magnetic field Hc2(T ) for the film with x = 0.01. From the slope of dHc2/dT , we obtain the coherence length ζ(0) ≈10 nm at T = 0 K and a coefficient of electronic heat capacity that is small compared with those of other oxide materials. [ABSTRACT FROM AUTHOR]

The present study deals with structural and optoelectronic properties of Cd(OH) 2 /CdO nanocomposite synthesized via co-precipitation method. The nanopowder was completely transformed into cadmium oxide after annealing at 750 °C for 2h. The nanocrystallites are having plate like planer morphology. In annealed samples, marigold and rose flower like surface morphology has been appeared. Average nanocrystallite size was obtained 10 and 25 nm for Cd(OH) 2 and CdO structure. The texture coefficient and degree of preferred orientation was evaluated from XRD peaks of the CdO. Comparative study of absorbance reveals the formation of Cd(OH) 2 /CdO composite with E g = 4.04–4.45 eV. PL results showed emission peaks at 409, 430, 463 and 530 nm that were originated through different mechanism. Investigation of resistivity, mobility and carrier concentration was examined to establish the conducting nature of the prepared nanocomposite. Optoelectronic properties are influenced by the alteration from the perfect CdO stoichiometry, nanocrystallite size and morphology. [ABSTRACT FROM AUTHOR]