共查询到20条相似文献,搜索用时 15 毫秒
1.
S. N. Kravchun S. T. Davitadze N. S. Mizina B. A. Strukov 《Physics of the Solid State》1997,39(4):675-680
The foundations of the theory underlying a method for measuring the thermal properties of anisotropic solids and thin dielectric
films deposited on them are examined. An analysis of the solutions is performed, making it possible to establish the limiting
possibilities of the periodic-heating technique and the conditions needed for an experiment that would permit measurement
of the specific heat and the thermal conductivity of films with good accuracy.
Fiz. Tverd. Tela (St. Petersburg) 39, 762–767 (April 1997) 相似文献
2.
G. Burrafato S. O. Troja E. Turrisi G. N. Marletta A. Torrisi 《Il Nuovo Cimento D》1988,10(4):463-471
Summary The morphological structure of SnTe very thin films is here studied by X-ray photoemission spectroscopy, by transmission electron
spectroscopy and by X-ray diffraction. The analisys of experimental data evidences the superficial confinement of Sn, with
different oxidation states, and the Te excess in the inner layers. The energy shift of the valence band peaks is attributed
to modifications induced by the nonstoichiometry of the compound. Preliminary Hall and resistivity measurements seem to confirm
the structural obtained results. 相似文献
3.
Thin films of ZnO have been prepared on glass substrates at different thicknesses by spray pyrolysis technique using 0.2 M aqueous solution of zinc acetate. X-ray diffraction reveals that the films are polycrystalline in nature having hexagonal wurtzite type crystal structure. The resistivity at room temperature is of the order 10−2 Ω cm and decreased as the temperature increased. Films are highly transparent in the visible region. The dependence of the refractive index, n, and extinction coefficient, k, on the wavelength for a sprayed film is also reported. Optical bandgap, Eg, has been reported for the films. A shift from Eg = 3.21 eV to 3.31 eV has been observed for deposited films. 相似文献
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5.
Thermal evaporated thin Sn?O films subjected to annealing treatments in air in the range 473–1173 K and in Ar in the range 473–773 K followed by annealings in air up to 1373 K were studied by CEMS (Conversion Electron Mössbauer Spectroscopy). Complementary Mössbauer and X-ray measurements were also performed on SnO powder that underwent the same series of annealings. The presence of the intermediate oxide Sn3O4 was detected. A temptative hyperfine characterization for the Sn2+ site in Sn3O4 is given. 相似文献
6.
S.K. Pandey O.P. ThakurR. Raman Anshu GoyalAmita Gupta 《Applied Surface Science》2011,257(15):6833-6836
We report on the structural and optical properties of yttria stabilized zirconia (YSZ) thin films grown by pulsed laser deposition (PLD) technique and in situ crystallized at different substrate temperatures (Ts = 400 °C, 500 °C and 600 °C). Yttria-stabilized zirconia target of ∼1 in. diameter (∼95% density) was fabricated by solid state reaction method for thin film deposition by PLD. The YSZ thin films were grown on an optically polished quartz substrates and the deposition time was 30 min for all the films. XRD analysis shows cubic crystalline phase of YSZ films with preferred orientation along 〈1 1 1〉. The surface roughness was determined by AFM for the films deposited at different substrate temperatures. The nano-sized surface roughness is found to increase with the increase of deposition temperatures. For the optical analysis, a UV-vis-NIR spectrophotometer was used and the optical band gap of ∼5.7 eV was calculated from transmittance curves. 相似文献
7.
This paper presents the physical properties of vacuum evaporated CdTe thin films with post-deposition thermal annealing. The thin films of thickness 500 nm were grown on glass and indium tin oxide (ITO) coated glass substrates employing thermal vacuum evaporation technique followed by post-deposition thermal annealing at temperature 450 °C. These films were subjected to the X-ray diffraction (XRD),UV-Vis spectrophotometer, source meter and atomic force microscopy (AFM) for structural, optical, electrical and surface morphological analysis respectively. The X-ray diffraction patterns reveal that the films have zinc-blende structure of single cubic phase with preferred orientation (111) and polycrystalline in nature. The crystallographic and optical parameters are calculated and discussed in brief. The optical band gap is found to be 1.62 eV and 1.52 eV for as-grown and annealed films respectively. The I–V characteristics show that the conductivity is decreased for annealed thin films. The AFM studies reveal that the surface roughness is observed to be increased for thermally annealed films. 相似文献
8.
《Superlattices and Microstructures》1998,24(1):79-82
Using an atomic force microscope (AFM) operating in air, we locally modify thin films of e-beam-deposited Cr and Ti by applying voltage pulses between the AFM tip and the sample, which is positively biased with respect to the tip. The modifications consist in anodization and/or mechanical deformation and reach the metal/substrate interface. Metallic gates can thus be fabricated without pattern transfer. 相似文献
9.
A. Skumanich H. Dersch M. Fathallah N. M. Amer 《Applied Physics A: Materials Science & Processing》1987,43(4):297-300
The photothermal deflection technique has been extended as a contactless method to investigate thermal transport in thin films. A theoretical model is developed which quantitatively describes the transport behavior, and is shown to be in excellent agreement with experimental results. This approach yields the thermal diffusivity directly and in a spatially-resolved manner. 相似文献
10.
C. Chiliotte D. Prez Daroca G. Pasquini V. Bekeris C.-P. Li F. Casanova J.E. Villegas I.K. Schuller 《Physica B: Condensed Matter》2009,404(18):2809-2811
Pinning properties in 100 nm thick continuous and porous superconducting Nb films are examined by ac susceptibility and dc magnetization measurements. The Nb film was deposited on a smooth Si substrate, while the porous film, NbP, was deposited on an anodized Al oxide substrate. Pores or “antidots” 40 nm in diameter, 100 nm apart, form a triangular array. The porous film presents commensurate or matching field effects for applied magnetic fields where the magnetic flux threading each unit cell is an integer number of the flux quantum, where ac shielding capability and dc diamagnetic magnetization show an abrupt increase. The response to ac fields as a function of temperature and dc field provided a way to determine that NbP sample has higher pinning than the continuous one, and that TC suppression due to fluxoid quantization is not relevant for the investigated temperature range. 相似文献
11.
《Current Applied Physics》2010,10(6):1402-1406
Tin selenide alloy was synthesized by following simple chemical reaction method, at comparatively lower temperature of 100 °C, from alkaline medium using SnCl2.2H2O and selenium as source materials. Powder X-ray diffraction analysis reveals that the particle size of the synthesized product is in nanometer scale. Using the reaction product as source material, the SnSe films were deposited on glass substrates at room temperature, 150 °C, 250 °C, 350 °C and 450 °C. Structural, elemental, optical, surface morphological and electrical properties of the as deposited films were studied by X-ray diffraction, Energy Dispersive X-ray Analysis, UV-Vis-NIR, Scanning Electron Microscopy and Hall effect measurement techniques and the relevant details have been obtained. 相似文献
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13.
We report on zinc oxide (ZnO) thin films (d = 55-120 nm) prepared by thermal oxidation, at 623 K, of metallic zinc films, using a flash-heating method. Zinc films were deposited in vacuum by quasi-closed volume technique onto unheated glass substrates in two arrangements: horizontal and vertical positions relative to incident vapour. Depending on the preparation conditions, both quasi-amorphous and (0 0 2) textured polycrystalline ZnO films were obtained. The surface morphologies were characterized by atomic force microscopy and scanning electron microscopy. By in situ electrical measurements during two heating-cooling cycles up to a temperature of 673 K, an irreversible decrease of electrical conductivity of as flash-oxidized Zn films was revealed. The influence of deposition arrangement and oxidation conditions on the structural, morphological and electrical properties of the ZnO films is discussed. 相似文献
14.
B. A. Belyaev V. V. Tyurnev A. V. Izotov An. A. Leksikov 《Physics of the Solid State》2016,58(1):55-61
Components of the fields scattered by a periodic planar strip structure of thin magnetic films possessing a uniaxial magnetic anisotropy in the plane have been calculated using the phenomenological model. Regularities in the dependence of these fields on the design parameters of the structure have been studied. The results obtained agree with the numerical analysis of the micromagnetic model of this structure. It has been shown that, near the edges of strips magnetized orthogonally to the major axis, the components of the scattered field can exceed the external magnetizing field by a few orders of magnitude. This fact makes it possible to design highly efficient magnetoresistive elements on the basis of a strip structure of magnetic films and thin semiconductor films. 相似文献
15.
N. Bouhssira E. Tomasella A. Mosbah M.S. Aida M. Jacquet 《Applied Surface Science》2006,252(15):5594-5597
ZnO thin films were deposited by thermal evaporation of a ZnO powder. The as-deposited films are dark brown, rich zinc and present a low transmittance. Then, these films were annealed in air atmosphere at different temperatures between 100 and 400 °C. Their microstructure and composition were studied using XRD and RBS measurements respectively. By increasing the temperature, it was found that film oxidation starts at 250 °C. XRD peaks related to ZnO appear and peaks related to Zn decrease. At 300 °C, zinc was totally oxidised and the films became totally transparent. The electrical conductivity measurement that were carried out in function of the annealing temperature showed the transition from highly conductive Zn thin film to a lower conductive ZnO thin film. The optical gap (Eg) was deduced from the UV-vis transmittance, and its variation was linked to the formation of ZnO. 相似文献
16.
17.
采用溶胶凝胶法,结合旋转涂敷技术在石英衬底上制备了210—240nm厚度的ZnO∶In薄膜.使用掠角入射X射线衍射(GI_XRD)、常规X射线衍射、傅里叶变换红外光谱、原子力显微镜、光致发光谱以及不同入射角GI_XRD谱(α=1,2,3和5°)等手段,对不同掺杂浓度的ZnO∶In薄膜进行了结构分析.发现ZnO∶In薄膜内部是由大尺寸(002)晶向的无应力ZnO晶粒堆积而成,而薄膜表面主要是小尺寸的(002)和(103)晶粒,并且适量的In掺杂能有效改善ZnO薄膜内部的晶体结构特性.
关键词:
ZnO∶In薄膜
晶体结构
掠角入射X射线衍射
溶胶凝胶法 相似文献
18.
《Physics letters. A》2020,384(26):126199
In the present work, high quality Pb doped ZnS thin films were deposited on glass substrates at 450°C using spray ultrasonic technique. The dependence of the structural, morphological and optical properties of the films on the lead (Pb) doping amount was investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis–NIR spectrophotometry, and four-point method. The improvement of the obtained Pb:ZnS thin films properties were discussed as a function of Pb concentration (0.5 to 2 at.%). The average crystallite size of Pb:ZnS was found in the range of 25–37 nm. The scanning electron microscopy (SEM) reveals that the films are continuous, homogeneous and dense. The UV–vis–NIR spectroscopy characterizations demonstrated that all the films exhibit good transmittance (60–70%) in the visible region and their optical band gap energy () changes from 3.92 to 3.6 eV. The films electrical resistivity showed an apparent dependence on Pb content. 相似文献
19.
M. Dutta 《Applied Surface Science》2008,254(9):2743-2747
ZnO thin films are deposited on the glass substrates by sol-gel drain coating technique by varying the concentration of the sol. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were used to investigate the effect of sol concentration on the crystallinity and surface morphology of the films. The results show that with increase in sol concentration, the value of full width at half maximum (FWHM) of (0 0 2) peak decreases while the strain first increases and then decreases. The sol with higher concentration results in the increase in the grain size. The studies on the optical properties show that the band gap value increases from 3.27 to 3.3 eV when the sol concentration changes from 0.03 to 0.1 M. The photoconductivity studies reveal that the film for 0.05 M sol shows the maximum photoresponse for ultraviolet (UV) wavelength (<400 nm) which is co-related with the deep-level defects. The growth and decay of the photocurrent is found to be slowest for the same film. 相似文献
20.
O.G. Morales-Saavedra A. Ortiz Rebollo 《Journal of Physics and Chemistry of Solids》2007,68(8):1571-1582
Semiconductor molecular-material thin films of [6,13-Ac2-5,14-Me2-[14]-4,6,11,13-tetraenato-1,4,8,11-N4] and the bidentate amines 1,4-diaminebutane, 1,12-diaminedodecane and 2,6-diamineanthraquinone have been prepared by vacuum thermal evaporation on corning glass substrates and crystalline silicon wafers. The films thus obtained were characterized by infrared (FTIR), ultraviolet-visible (UV-VIS) and photoluminescence (PL) spectroscopies. The surface morphology, thickness and structure of these films were analyzed by atomic force microscopy (AFM), ellipsometry and X-ray diffraction (XRD), respectively. IR spectroscopy showed that the molecular-material thin films exhibit the same intra-molecular bonds as the original compounds, which suggests that the thermal evaporation process does not significantly alter their bonds. The effect of temperature on conductivity was also measured in these samples; it was found that the temperature-dependent electric current is always higher for the voluminous amines with large molecular weights and suggests a semiconductor behavior with conductivities in the order of 10−6-10−1 Ω−1 cm−1. Finally, the optical band gap (Eg) and cubic χ(3) non-linear optical (NLO) properties of these amorphous molecular complexes were also evaluated from optical absorption and optical third harmonic generation (THG) measurements, respectively. 相似文献