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1.
Ge0.7Mn0.3 thin films were fabricated on Al2O3 (0001) and glass substrates at growth temperatures ranging from room temperature to 500 °C by a radio frequency magnetron sputtering. We found that the Ge0.7Mn0.3 thin films showed a polycrystalline-to-amorphous transition at about 360 °C, and the ferromagnetic transition temperature of each thin film depends on its structure — crystalline or amorphous states. Particularly, the Ge0.7Mn0.3 thin films showed room temperature ferromagnetism when they were fabricated at temperatures above the crystallization temperature. 相似文献
2.
Conductive RuO2 thin films were epitaxially grown on LaAlO3(100) and MgO(100) substrates by metal-organic chemical vapor deposition (MOCVD). The deposited RuO2 films were crack-free, and well adhered to the substrates. The RuO2 film is (200) oriented on LaAlO3 (100) substrates at deposition temperature of 600°C and (110) oriented on MgO(100) substrates at deposition temperature of 350°C and above. The epitaxial growth of RuO2 on MgO and LaAlO3 is demonstrated by strong in-plane orientation of thin films with respect to the major axes of the substrates. The RuO2 films on MgO(100) contain two variants and form an orientation relationship with MgO given by RuO2(110)//MgO(100) and RuO2[001]//MgO[011]. The RuO2 films on LaAlO3(100), on the other hand, contain four variants and form an orientation relationship with LaAlO3 given by RuO2(200)//LaAlO3(100) and RuO2[011]//LaAlO3[011]. Electrical measurements on the RuO2 thin films deposited at 600°C show room-temperature resistivities of 40 and 50 μΩ cm for the films deposited on the MgO and LaAlO3 substrates, respectively. 相似文献
3.
MoS2 coatings, 55–800 nm thick, were grown by ion-beam-assisted deposition (IBAD) using different ion-to-atom ratios and deposition temperatures. Crystallinity and orientation of the IBAD MoS2 coatings were determined by X-ray diffraction (XRD). Only XRD peaks corresponding to (00l), (hk0), and amorphous MoS2, and a previously unreported low-2Θ peak (2Θ ≈ 10.7 °) were observed. The basal (002) peak intensities varied primarily with ion-to-atom ratio; the greatest basal intensity occurred when the ion-to-atom ratio produced about 1 displacement per atom. Although a secondary factor in basal intensity, deposition temperature was the primary factor in edge (100) intensity. Edge intensity increased with increasing temperature; it appears that the increases are due to annealing of randomly-oriented MoS2, which converts to edge orientation. The origin of the low-2Θ peak is unknown, but appears to be associated with the basal planes of MoS2. 相似文献
4.
Zirconium doped indium oxide thin films were deposited by the atomic layer deposition technique at 500 °C using InCl3, ZrCl4 and water as precursors. The films were characterised by X-ray diffraction, energy dispersive X-ray analysis and by optical and electrical measurements. The films had polycrystalline In2O3 structure. High transparency and resistivity of 3.7×10−4 Ω cm were obtained. 相似文献
5.
The growth structure of MgF2 and NdF3 films grown on polished CaF2(111) substrates deposited by molecular beam deposition has been investigated using transmission electron microscopy (TEM) of microfractographical and surface replications as well as cross-sectional TEM, atomic force microscopy, packing density, and absorption measurements. It has been shown that by taking advantage of ultrahigh vacuum environments and a special stratification property of MgF2 and NdF3 films, the preparation of nanocrystalline films of high packing density and low optical absorption is possible at a substrate temperature of 425 K. 相似文献
6.
Textured MoTe2 films have been prepared by sequential evaporation of the constituents followed by annealing under a tellurium pressure. The films are systematically textured with the c-axis of the crystallites perpendicular to the plane of substrate, however, the film composition is difficult to control and even after process optimization the films are tellurium deficient. This is thought to be caused by the electro negativity difference of the constituents.The textured MoTe2 films have been used as substrates on which to grow MoS2 films by annealing under a pressure of sulfur that allows textured MoS2 films to be grown with good crystalline properties. The presence of sulfur at the surface and annealing under dynamic vacuum is important for this process and moreover, suppresses the superficial oxidation of the Mo and Te constituents. 相似文献
7.
Hollow molybdenum disulfide (MoS2) microspheres were synthesized in ionic liquids (1-butyl-3-methylimidazolium chloride, [BMIM]Cl)/water binary emulsions by the hydrothermal method at 180 °C for 24 h. The optimum value of volumetric proportions (ILs/water) equaled 1:9. The structure and morphology of products were characterized by means of X-ray powder diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The experimental results gave the evidences that the sample is consists of hollow spheres 1.8 - 2.1 μm in diameter, and there are much sheet-like structures on the surface of hollow MoS2 microspheres. In addition, ILs could be collected and reused for subsequent reactions. 相似文献
8.
CaCu3Ti4O12 (CCTO) thin films were successfully deposited on Pt/Ti/SiO2/Si(1 0 0) substrates using pulsed-laser deposition technique. The crystalline structure and the surface morphology of the CCTO thin films were greatly affected by the substrate temperature and oxygen pressure. Thin films with a (2 2 0) preferential orientation were obtained at the substrate temperature above 700 °C and oxygen pressure above 13.3 Pa. The 480-nm thin films deposited under 720 °C and 26.6 Pa have a fairly high dielectric constant of near 2000 at 10 kHz and room temperature. The values of the dielectric constant and loss and their temperature-dependence under different frequency are comparable with those obtained in the epitaxial CCTO films grown on oxide substrates. 相似文献
9.
The LiNbO3 thin films are successfully grown by pulsed-laser deposition on theAl0.28Ga0.72N/GaN substrate. The films are characterized by the X-ray diffraction and the X-ray photoelectron spectroscopy. The ferroelectric properties are measured by the piezoresponse force microscopy. An Al/SiO2/LiNbO3/Al0.28Ga0.72N/GaN structure is then fabricated and measured by high frequency capacitance-voltage at 1 MHz. The mechanism of interaction between interfaces is revealed. 相似文献
10.
Multiple inorganic fullerene-like (IF) molybdenum disulfide hollow spheres were synthesized through spray drying method. The molybdenum trisulfide precursor, which was prepared by the mixed solution of ammonium molybdate ((NH4)2MoO4) and ammonium disulfide ((NH4)2S) with a spray drying method, was desulfurized at 850 °C in a mixture of hydrogen and argon, and subsequently multiple fullerene-like molybdenum disulfide hollow spheres were obtained. The samples were identified and characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM), and the mechanism of formation is also discussed based on the experimental result. The spray drying process would be an effective method to synthesize large-scale of inorganic fullerene-like materials. 相似文献
11.
Sung-Kun Park 《Thin solid films》2004,457(2):397-401
The structural properties of a potassium lithium niobate (KLN; K3Li2Nb5O15) thin film deposited by rf-magnetron sputtering on a Pt/Ti/SiO2/Si(100) substrate were investigated. The crystalline structures of the Pt under layer and KLN thin films were examined using θ-2θ, θ-rocking, and mesh scan X-ray diffraction (XRD). The XRD results revealed that the Pt under layer was a strong (111) direction orientated poly crystal. Unlike the Pt under layer film, the KLN(001) peak was found to consist of two separate peaks, one with a broad full width half maximum (FWHM) and the other with a narrow FWHM, indicating that the KLN film had a single crystalline structure. The surface and cross-section morphology were investigated using a scanning electron microscope (SEM). Accordingly, from the results of the SEM and XRD experiments, it was concluded that the KLN film was composed of small single crystals, which had a four-fold symmetry morphology with a c-axis normal to the substrate. 相似文献
12.
Fe-O thin films with different atomic ratio of iron to oxygen were deposited on glass and thermally oxidized silicon substrates at temperatures of 300, 473 and 593 K, by reactive magnetron sputtering in Ar+O2 atmosphere. The composition and structure of the thin films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electrical resistivity. It was found from XRD that with increasing the oxygen partial pressure in the working gas, the crystalline structure of the Fe-O films deposited at the substrate temperature of 473 K gradually changed from α-Fe, amorphous Fe-O, Fe3O4, γ-Fe2O3 to Fe21.34O32. The structure and chemical valence of the Fe3O4 films were analyzed by electron microscopy and XPS, respectively. 相似文献
13.
As the first stage for thin film preparation of copper indium disulfide (CuInS2), an electrodeposition technique of thin films in the Cu---S system was investigated from a new viewpoint. Deposition was carried out potentiostatically on a Ti substrate from acidic aqueous solution containing CuSO4 and Na2S2O3. Tartaric acid was found to be effective as a buffer for stabilizing the hydrogen ion concentration. Thin films of Cu2S were obtained at −0.7 V vs. Ag/AgCl with good reproducibility from a solution containing 10 mM CuSO4, 400 mM Na2S2O3 and 100 mM tartaric acid. Scanning electron microscopy and energy dispersive X-ray analyses revealed that the film deposited had a crack-free surface and uniform stoichiometry of Cu2S. Film thickness was estimated to be 0.6−0.8×10−6m after 3600 s deposition. The mechanism of Cu2S formation was supposed to be that S2O32− ion reduces Cu(II) ion to make complex with Cu(I) ion. Probably it is this complex that contributes to the Cu2S formation. 相似文献
14.
CeO2 and Ce/V mixed oxide thin films prepared by sol-gel deposition and annealed in an air or argon atmosphere have been studied by chronocoulometry and by XAFS (X-ray absorption fine structure). Multielectron photoexcitations (MPE), well known to pervade XAFS spectra of Ce making the analysis of structural parameters unreliable, are removed with the help of the atomic absorption background, determined on simple Ce compounds. Distinct MPE estimates for Ce3+ and Ce4+ ions are used. In the analysis of the recovered pure XAFS signal, the degree of disorder is found to depend on the Ce/V molar ratio and on the heating atmosphere. The disorder correlates with charge capacity of films, both increasing with vanadium content and V4+/V5+ molar ratio. 相似文献
15.
Titanium dioxide thin films were deposited by Metallorganic Chemical Vapor Deposition at substrate temperatures ranging from 250 °C to 450 °C over soda lime glass and indium tin oxide coated glass substrates. X-ray diffraction studies show that films have a crystalline anatase structure at all the deposition temperatures. Particle size decreases and texture changes with the increase in substrate temperature. X-ray photoelectron spectroscopy confirms the appearance of a new well resolved state in the core level of Ti 2p spectrum shifted by 1.16 eV to lower binding energy due to the reduction of Ti+ 4 to Ti+ 3 upon litheation. Chronoamperometery, cyclic voltammetery and in situ UV-Vis spectrophotometeric studies were carried out on the prepared samples. Particle size and crystallinity control the electrochromic performance. The 350 °C film shows the highest ion storage capacity and the highest optical modulation along with an appreciable band gap broadening. 相似文献
16.
William B Ingler Jr 《Thin solid films》2004,461(2):301-308
Stable Mg-doped iron (III) oxide thin film electrodes that exhibit p-type behavior were synthesized by spray pyrolytic methods on indium doped tin oxide-coated glass substrate. The highest photocurrent density of 0.22 mA/cm2 was observed for Mg-doped p-Fe2O3 samples prepared at the optimal substrate temperature of 390 °C at 0.2 V/SCE. The total spray time for optimized photoconversion efficiency of 0.33% was found to be at 130 s for a spray period of 10 s. X-Ray diffraction (XRD) studies revealed mixed structures (α and γ-Fe2O3 and MgO) for the Mg-doped p-Fe2O3 thin films. 相似文献
17.
The conditions for the layer-by-layer synthesis by the method of the successive ionic layer deposition of Sn(IV)Mo(VI,V)0.6Oy·nH2O nanolayers on a silica surface were determined for the first time. The nanolayer thickness was controlled by the number of successive cycles. The composition and structure of these films were determined using Fourier transform infrared and UV/Vis transmission spectroscopy, X-ray photoelectron spectroscopy, X-ray difraction, and electron microprobe. It was found that under heating up to 200 °C, molecular water and hydroxyl groups are removed from the nanolayers, the bonds Mo---O---Mo and Sn---O---Mo are formed, and Mo(V) is oxidized to Mo(VI). 相似文献
18.
Poulomi Roy 《Thin solid films》2006,496(2):293-298
Molybdenum disulphide, MoS2, thin films have been deposited by chemical bath deposition method on glass and quartz substrate using ammonium tetrathiomolybdate as a single source precursor for Mo and S and subjected to vacuum heat treatment at different temperatures. X-ray diffraction of as-deposited film indicated its amorphous character and showed the development of poorly crystalline MoS2 thin film on increasing annealing temperature. The film has been characterized by energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, scanning electron micrograph and the optical properties also have been studied. 相似文献
19.
Liquid phase deposition method is applied to one-step production of a hybrid material composed by dopamine(DA) and TiO2 anatase. An optimized amount of the enediol derivative is added to a fluoride titania precursor aqueous solution in order to entrap this modifier within the growing TiO2, yielding a DA/TiO2 nanocomposite material. Uniform, well-adhered and brown-colored thin films are deposited on indium tin oxide covered glass substrate. The DA/TiO2 hybrid material has been characterized by infrared spectroscopy, electronic microscopy, X-ray diffraction and UV-vis spectroscopy. The formation of the hybrid material seems to be reasonably explained by linkage of different TiO2 nanocrystallites taking advantage of both enediol and amine groups of DA. 相似文献
20.
Copper indium disulphide, CuInS2, is a promising absorber material for thin film photovoltaic which has recently attracted considerable attention due to its suitability to reach high efficiency solar cells by using low-cost techniques. In this work CuInS2 thin films have been deposited by chemical spray pyrolysis onto glass substrates at ambient atmosphere, using different composition solutions at various substrate temperatures. Structural, chemical composition and optical properties of CIS films were analysed by X-ray diffraction, energy dispersive X-ray spectroscopy and optical spectroscopy. Sprayed CIS films are polycrystalline with a chalcopyrite structure with a preferential orientation along the <112> direction and no remains of oxides were found after spraying in suitable conditions. X-ray microanalysis shows that a chemical composition near to stochiometry can be obtained. An optical gap of about 1.51 eV was found for sprayed CIS thin films. 相似文献