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1.
Thin metal oxide films for a WO3-based symmetric electrochromic system with a nickel oxide layer as the counter electrode have been prepared by spray pyrolysis on SnO2:F coated soda-lime float glass, at a temperature of 670–720 °C and using metal acetylacetonates as precursors. The films have been characterized for composition and morphology by scanning electron microscopy equipped with an X-ray energy dispersive analyzer (SEM/EDAX), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Electrochromic properties have been examined in the electrochemical cells of a smart window arrangement using lithium ion doped sol–gel derived organic–inorganic hybrid materials as electrolytes. Hybrids with room-temperature ionic conductivities of 10?4–10?3 Ω?1 cm?1 have been synthesized from tetraethyl orthosilicate (TEOS) with an addition of 35 mass % of organic compounds. Coloration-bleaching of WO3 films with lithium ions from hybrid electrolytes has resulted in the desired modulating the properties in the visible and near infrared spectrum range. An XPS analysis has shown the presence of a lower oxidized tungsten oxide phase (WO2.92) in the WO3 film. 相似文献
2.
M. Zaharescu V.S. Teodorescu M. Gartner M.G. Blanchin A. Barau M. Anastasescu 《Journal of Non》2008,354(2-9):409-415
This work describes the preparation of HfO2 thin films by the sol–gel method, starting with different precursors such as hafnium ethoxide, hafnium 2,4-pentadionate and hafnium chloride. From the solution prepared as mentioned above, thin films on silicon wafer substrates have been realized by ‘dip-coating’ with a pulling out speed of 5 cm min?1. The films densification was achieved by thermal treatment for 10 min at 100 °C and 30 min at 450 °C or 600 °C, with a heating rate of 1 °C min?1. The structural and optical properties of the films are determined employing spectroellipsometric (SE) measurements in the visible range (0.4–0.7 μm), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The main objective of this paper was to establish a correlation between the method of preparation (precursor, annealing temperature) and the properties of the obtained films. The samples prepared from pentadionate and ethoxide precursors are homogenous and uniform in thickness. The samples prepared starting from chloride precursor are thicker and proved to be less uniform in thickness. Higher non-uniformity develops in multi-deposition films or in crystallized films. A nano-porosity is present in the quasi-amorphous films as well in the crystallized one. For the samples deposited on silicon wafer, the thermal treatment induced the formation of a SiO2 layer at the coating–substrate interface. 相似文献
3.
《Journal of Non》2007,353(18-21):1818-1823
This work presents a structural investigation of Li-borate thin film electrolytes prepared by rf-sputtering from targets having the nominal Li2O–2B2O3 composition. Thin films of ca. 1 μm were deposited on Si wafers and gold-covered Si substrates under argon, and their infrared spectra were measured in the 30–5000 cm−1 range. The measured spectra of thin films were compared with those calculated on the basis of the infrared properties of the bulk Li-diborate glass and by considering all optical effects in the film/substrate system. The results showed that the thin films have the key structural features of the bulk glass, but exhibit also differences in the short-range order structure and in the Li ion-site interactions. These findings were discussed in terms of cooling rate differences between melt-quenching for bulk glass and sputtering for thin films. 相似文献
4.
Ga5Ge15Te80 thin films have been deposited by e-beam evaporation method. The chemical composition of the deposited films was identified using energy dispersive X-ray spectrometry. The electrical conductivity, σ of the deposited films during heating/cooling cycles was investigated in the temperatures 298–570 K. The conductivity curve showed two sudden upward trends during the first heating cycle. The first upward trend occurs in the temperature range 408–430 K and was attributed to the amorphous-to-crystalline phase transformation. While the second is in the temperature range 470–495 K, and can be attributed to the crystallization process. However, for second heating cycle the conductivity curve becomes reversible. The optical band gap of the as-deposited and annealed film at annealing temperature 423 K was determined from the recorded transmittance and reflectance spectra. The obtained results were confirmed throughout the X-ray and transmission electron microscope studies. 相似文献
5.
Jun Du Piyi Du Ming Xu Gaorong Han Wenjian Weng Jianxun Wang 《Journal of Non》2008,354(12-13):1308-1313
Titanium silicide thin films were prepared on glass substrates by chemical vapor deposition using SiH4 and TiCl4 as the precursors. The phase structure of the thin films was identified by XRD. The surface morphology of the thin films was observed by FESEM. The sheet resistance and optical behaviors of the thin films were measured by the four point resistivity test system and FTIR spectrometer, respectively. Titanium disilicide (TiSi2) thin films with the face-centered orthorhombic structure are formed. The suitable formation temperature of the TiSi2 crystalline phase is about 710 °C. The formation of TiSi2 crystalline phase is dependent on the thickness of thin films and a quantity of the crystalline phase of TiSi2 in the thin film is directly related to mole ratio of SiH4/TiCl4. The sheet resistance of the TiSi2 thin films is dependent on the formation of the TiSi2 crystalline phase. With the mole ratio of SiH4/TiCl4 of 3, the lowest sheet resistance (0.7 Ω/□) of titanium silicide thin film is formed at 710 °C. The maximum reflectance of the TiSi2 thin films is about 0.95 on the broad IR heat radiation. A related reaction mechanism was proposed. 相似文献
6.
In this paper amorphous ZrO2 and HfO2 thin films were obtained by direct UV irradiation of Zr(IV) and Hf(IV) β-diketonate precursor complexes on Si(1 0 0) and fused silica substrates. The precursors, Zr(CH3COCHCOCH3)4 and Hf(C6H5COCHCOCH3)4 were deposited as amorphous thin films by spin coating. The photochemistry of these films was monitored by FT-IR spectroscopy. The photolysis with 254 nm light led to the loss of the ligands from the coordination complexes, and the production of metallic oxides. The thin films products were characterized by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). These analyses revealed that as-deposited films are amorphous and that the presence of carbon is thought to arise from the ligands. However, post-annealing of the photodeposited films favors the stoichiometric and optical properties of ZrO2 and HfO2 thin films. 相似文献
7.
《Journal of Crystal Growth》2006,286(2):376-383
Bismuth silicate and bismuth titanate thin films were deposited by atomic layer deposition (ALD). A novel approach with pulsing of two Bi-precursors was studied to control the Si/Bi atomic ratio in bismuth silicate thin films. The crystallization of compounds formed in the Bi2O3–SiO2 and Bi2O3–TiO2 systems was investigated. Control of the stoichiometry of Bi–Si–O thin films was studied when deposited on Si(1 0 0) and crystallization was studied for films on sapphire and MgO-, ZrO2- and YSZ-buffered Si(1 0 0). The Bi–Ti–O thin films were deposited on Si(1 0 0) substrate. Both Bi–Si–O and Bi–Ti–O thin films were amorphous after deposition. Highly a-axis oriented Bi2SiO5 thin films were obtained when the Bi–Si–O thin films deposited on MgO-buffered Si(1 0 0) were annealed at 800 °C in nitrogen. The full-width half-maximum values for 200 peak were also studied. An excess of bismuth was found to improve the crystallization of Bi–Ti–O thin films and the best crystallinity was observed with Ti/Bi atomic ratio of 0.28 for films annealed at nitrogen at 1000 °C. Roughness of the thin films as well as the concentration depth distribution were also examined. 相似文献
8.
《Journal of Non》2006,352(23-25):2367-2370
Epitaxial layers of up to 50% Yb-doped monoclinic KLu(WO4)2 could be successfully grown on passive KLu(WO4)2 substrates. These composite samples were characterized and continuous-wave and mode-locked laser operation was achieved with Ti:sapphire and diode-laser pumping. A 10% Yb-doped epitaxy provided an output power exceeding 500 mW at 1030 nm and a maximum slope efficiency of 66% with Ti:sapphire laser pumping. A 50% Yb-doped epitaxy exhibited serious thermal problems without special cooling and rather limited cw performance. Quasi-cw operation provided in this case an average output power of 43 mW at 1032 nm for a 10% duty cycle. More than 100 mW cw could be generated at 1030 nm also with diode-pumping of the 10% Yb-doped KLu(WO4)2 epitaxy. Pulses as short as 114 fs were generated at 1030 nm with this same sample under Ti:sapphire laser pumping in a laser mode-locked by a saturable absorber mirror. 相似文献
9.
《Journal of Crystal Growth》2003,247(3-4):393-400
Using a highly conductive ZnO(ZnAl2O4) ceramic target, c-axis-oriented transparent conductive ZnO:Al2O3 (ZAO) thin films were prepared on glass sheet substrates by direct current planar magnetron sputtering. The structural, electrical and optical properties of the films (deposited at different temperatures and annealed at 400°C in vacuum) were characterized with several techniques. The experimental results show that the electrical resistivity of films deposited at 320°C is 2.67×10−4 Ω cm and can be further reduced to as low as 1.5×10−4 Ω cm by annealing at 400°C for 2 h in a vacuum pressure of 10−5 Torr. ZAO thin films deposited at room temperature have flaky crystallites with an average grain size of ∼100 nm; however those deposited at 320°C have tetrahedron grains with an average grain size of ∼150 nm. By increasing the deposition temperature or the post-deposition vacuum annealing, the carrier concentration of ZAO thin films increases, and the absorption edge in the transmission spectra shifts toward the shorter wavelength side (blue shift). 相似文献
10.
S.K. Sharma Krishnankutty-Nair P. Kumar K.J. Kang R.M. Mehra 《Journal of Non》2009,355(31-33):1638-1643
Hydrogenated amorphous silicon thin films doped with chalcogens (Se or S) were prepared by the decomposition of silane (SiH4) and H2Se/H2S gas mixtures in an RF plasma glow discharge on 7059 corning glass at a substrate temperature 230 °C. The illumination measurements were performed on these samples as a function of doping concentration, temperature and optical density. The activation energy varied with doping concentration and is higher in Se-doped than S-doped a-Si:H thin films due to a low defect density. From intensity versus photoconductivity data, it is observed that the addition of Se and S changes the recombination mechanism from monomolecular at low doping concentration films to bimolecular at higher doping levels. The photosensitivity (σph/σd) of a-Si, Se:H thin films decreases as the gas ratio H2Se/SiH4 increased from 10?4 to 10?1, while the photosensitivity of a-Si, S:H thin films increases as the gas ratio H2S/SiH4 increased from 6.8 × 10?7 to 1.0×10?4. 相似文献
11.
《Journal of Crystal Growth》2006,286(2):371-375
It is well known that there is an upper limit (<0.25 μm) for the thickness of hydrothermal thin films grown on Ti substrate in the 100–200 °C temperature range, even the reaction time is extended to several weeks. In this paper, BaTiO3 thin films have been firstly hydrothermally synthesized on titanium substrates covered with a nanoporous TiO2 layer. By using TiO2 covered substrates, the thickness of BaTiO3 films can easily reach ∼1.0 μm at 110 °C after only 2 h hydrothermal treatment. It is found that the large quantity of pores with size at the tens of nanometer range in the oxide layer served as easy paths for the diffusion of Ba2+ and OH− and enabled the film grow thicker. SEM and XRD results show that the films are crack-free and in polycrystalline phase. 相似文献
12.
X.T. Li B. Wang W.J. Weng G.R. Han C.L. Song N. Ma P.Y. Du 《Journal of Crystal Growth》2011,314(1):104-107
Highly (1 0 0)-oriented Pb0.4Sr0.6TiO3 (PST40) thin films have been prepared on the Tb doped PbTiO3 (PTT) thin film coated ITO/glass substrate by sol–gel technique. The PTT inducing layers are (1 0 0)-oriented and can help to control the orientation of PST40 thin films. Crystallization of the PST40 thin film with the PTT inducing layer is more perfect than that without PTT layer due to less distortion in the thin film. The dielectric tunability of the PST40 thin film with PTT layer therefore reaches 65%, which is 85% higher than that without PTT layer. The dielectric loss of the PST thin film is only 0.05. These results indicate that (1 0 0)-oriented Tb doped PbTiO3 can be used as an inducing layer for highly (1 0 0)-oriented tunable materials on ITO/glass substrate. 相似文献
13.
Tokiyoshi Matsuda Mamoru Furuta Takahiro Hiramatsu Chaoyang Li Hiroshi Furuta Hitoshi Hokari Takashi Hirao 《Journal of Crystal Growth》2008,310(1):31-35
Undoped ZnO films were deposited by radio frequency (RF) magnetron sputtering on amorphous buffer layers such as SiOx, SiOxNy, and SiNx prepared by plasma enhanced chemical vapor deposition (PECVD) for dielectric layer in thin film transistor (TFT) application. ZnO was also deposited directly on glass and quartz substrate for comparison. It was found that continuous films were formed in the thickness up to 10 nm on all buffer layers. The crystallinity of ZnO films was improved in the order on quartz>SiOx >SiOxNy>glass>SiNx according to the investigated intensities of (0 0 2) XRD peaks. The crystallite sizes of ZnO were in the order of SiOx~glass >SiNx. Stable XRD parameters of ZnO thin films were obtained to the thickness from 40 to 100 nm grown on SiOx insulator for TFT application. Investigation of the ZnO thin films by atomic force microscope (AFM) revealed that grain size and roughness obtained on SiNx were larger than those on SiOx and glass. Hence, both nucleation and crystallinity of sputtered ZnO thin films remarkably depended on amorphous buffer layers. 相似文献
14.
《Journal of Crystal Growth》2006,286(2):407-412
The copper nitride thin films were prepared on glass substrate by RF magnetron sputtering method. At pure nitrogen atmosphere, the nitrogen flow rate affects the copper nitride thin films’ structures. Only a little part of nitrogen atoms insert into the body center of Cu3N structure and parts of nitrogen atoms insert into Cu3N crystallites boundary at higher nitrogen flow rate. But the indirect optical energy gap, Eopg, decreases with increasing nitrogen flow rate. The typical value of Eopg is 1.57 eV. In a nitrogen and argon mixture atmosphere, when the nitrogen partial was less than 0.2 Pa at 50 sccm total flow rate, the (1 1 1) peak of copper nitride appears. Thermal decomposition temperature of Cu3N thin films deposited in pure nitrogen and 30 sccm flow rate was less than 300 °C. The surface morphology was smooth. 相似文献
15.
The growth and characterization of zirconium oxide (ZrO2) thin films prepared by thermal oxidation of a deposited Zr metal layer on SiO2/Si were investigated. Uniform ZrO2 thin film with smooth surface morphology was obtained. The thermal ZrO2 films showed a polycrystalline structure. The dielectric constant of the ZrO2 film has been shown to be 23, and the equivalent oxide thickness (EOT) of the ZrO2 stacked oxide is in the range of 3.38–5.43 nm. MOS capacitors with ZrO2 dielectric stack show extremely low leakage current density, less than 10?6 A/cm2 at ?4 V. Consequently, using this method, high-quality ZrO2 films could be fabricated at oxidation temperature as low as 600 °C. 相似文献
16.
Cu(In,Ga)Se2 polycrystalline thin films were deposited adopting the potentiostatic electrochemical method on Mo/soda lime glass substrate. All the as-deposited Cu(In,Ga)Se2 thin films were annealed in a selenium atmosphere at 550 °C for 1 h to improve the film crystalline properties. The selenized CIGS thin films were characterized by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and scanning electron microscopy (SEM).The results indicate Cu(In,Ga)Se2 thin films have single chalcopyrite structure and the grain size varies from 0.8 to 2.5 μm. 相似文献
17.
Li+ ion conducting Li–Al–Ti–P–O thin films were fabricated on ITO-glass substrates at various temperatures from 25 to 400 °C by RF magnetron sputtering method. When the substrate temperature is higher than 300 °C, severe destruction of ITO films were confirmed by XRD (X-ray diffraction) and the abrupt transformation of one semi-circle into two semi-circles on the impedance spectra. These as-deposited Li–Al–Ti–P–O solid state electrolyte thin films have an amorphous structure confirmed by XRD and a single semicircle on the impedance spectra. Good transmission higher than 80% in the visible light range of these electrolyte thin films can fulfill the demand of electro-chromic devices. Field emission scanning electron microscopy and atomic force microscopy showed the denser, smoother and more uniform film structure with the enhanced substrate temperature. Measurements of impedance spectra indicate that the gradual increased conductivity of these Li–Al–Ti–P–O thin films with the elevation of substrate temperature from room temperature to 300 °C is originated from the increase of the pre-exponential factor (σ0). The largest Li-ion conductivity can come to 2.46 × 10? 5 S cm? 1. This inorganic solid lithium ion conductor film will have a potential application as an electrolyte layer in the field such as lithium batteries or all-solid-state EC devices. 相似文献
18.
The glasses representing (Bi2O3)x(WO3)y(TeO2)100?x?y and (PbO)x(WO3)y(TeO2)100?x?y systems were prepared. The dilatometric glass-transition temperatures of examined glass samples were found in the region 383–434 °C, the coefficient of thermal expansion varied from 12 to 16 ppm/°C and the density ranged from 6.302 to 6.808 g/cm3. From the optical transmission measurements of thin glassy bulk samples prepared by a glass blowing, the optical gap values were found in the narrow region 3.21–3.36 eV. For the temperature interval 300–480 K, the values of the temperature coefficient of the optical band gap varied from 3.7 × 10?4 to 5.24 × 10?4 eV/K. It is suggested that Raman feature observed at around 350 cm?1 can be assigned to an overlap of Raman bands attributed to WO6 corner shared octahedra and to the following three atomic linkages: Bi–O–Te, Pb–O–Te and W–O–Te. 相似文献
19.
《Journal of Crystal Growth》2003,247(3-4):497-504
Structural, morphological, optical and electrical properties of ZnO thin films prepared by chemical spray pyrolysis from zinc acetate (Zn(CH3COO)2 2H2O) aqueous solutions, on polished Si(1 0 0), and fused silica substrates for optical characterization, have been studied in terms of deposition time and substrate temperature. The growth of the films present three regimes depending on the substrate temperature, with increasing, constant and decreasing growth rates at lower, middle, and higher-temperature ranges, respectively. Growth rate higher than 15 nm min−1 can be achieved at Ts=543 K. ZnO film morphological and electrical properties have been related to these growth regimes. The films have been characterized by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. 相似文献
20.
Y. Lin A.G. Norman W.E. McMahon H.R. Moutinho C.-S. Jiang A.J. Ptak 《Journal of Crystal Growth》2011,314(1):298-301
Al thin films have been grown on single-crystal MgAl2O4 spinel substrates using solid source molecular beam epitaxy. The structural properties of Al layers were systematically investigated as a function of substrate orientation. X-ray diffraction reveals that Al layers are coherently grown on both (0 0 1)- and (1 1 1)-oriented spinel substrates. However, scanning electron microscopy and atomic force microscopy show that Al layers on (0 0 1) spinel substrates display smoother surface morphology than those grown on (1 1 1) spinel substrates. Additionally, electron backscatter diffraction and transmission electron microscopy demonstrate the presence of a high density of twin domain structures in Al thin films grown on (1 1 1) spinel substrates. 相似文献