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1.
K. Venkata Subba Reddy A. Sivasankar Reddy P. Sreedhara Reddy S. Uthanna 《Journal of Materials Science: Materials in Electronics》2007,18(10):1003-1008
Copper nitride (Cu3N) films were deposited on glass substrates by sputtering of copper target under various substrate temperatures in the range
303–523 K using dc reactive magnetron sputtering. The substrate temperature highly influenced the structural, mechanical,
electrical and optical properties of the deposited films. The X-ray diffraction measurements showed that the films were of
polycrystalline nature and exhibit preferred orientation of (111) phase of Cu3N. The microhardness of the films increased from 2.7 to 4.4 GPa with the increase of substrate temperature from 303 to 473 K
thereafter decreased to 4.1 GPa at higher temperature of 523 K. The electrical resistivity of the films decreased from 8.7 × 10−1 to 1.1 × 10−3 Ωcm and the optical band gap decreased from 1.89 to 1.54 eV with the increase of substrate temperature from 303 to 523 K
respectively. 相似文献
2.
M. Öztaş M. Bedir R. Kayalı F. Aksoy 《Journal of Materials Science: Materials in Electronics》2006,17(10):841-845
InP thin films were prepared by spray pyrolysis technique using aqueous solutions of InCl3 and Na2HPO4, which were atomized with compressed air as carrier gas. The InP thin films were obtained on glass substrates. Thin layers
of InP have been grown at various substrate temperatures in the range of 450–525°C. The structural properties have been determined
by using X-ray diffraction (XRD). The changes observed in the structural phases during the film formation in dependence of
growth temperatures are reported and discussed. Optical properties, such as transmission and the band gap have been analyzed.
An analysis of the deduced spectral absorption of the deposited films revealed an optical direct band gap energy of 1.34–1.52 eV
for InP thin films. The InP films produced at a substrate temperature 500°C showed a low electrical resistivity of 8.12 × 103 Ω cm, a carrier concentration of 11.2 × 1021 cm−3, and a carrier mobility of 51.55 cm2/Vs at room temperature. 相似文献
3.
Transparent conducting tin oxide thin films have been prepared by electron beam evaporation and spray pyrolysis methods. Structural,
optical and electrical properties were studied under different preparation conditions like substrate temperature, solution
flow rate and rate of deposition. Resistivity of undoped evaporated films varied from 2.65 × 10−2 ω-cm to 3.57 × 10−3 ω-cm in the temperature range 150–200°C. For undoped spray pyrolyzed films, the resistivity was observed to be in the range
1.2 × 10−1 to 1.69 × 10−2 ω-cm in the temperature range 250–370° C. Hall effect measurements indicated that the mobility as well as carrier concentration
of evaporated films were greater than that of spray deposited films. The lowest resistivity for antimony doped tin oxide film
was found to be 7.74 × 10−4 ω-cm, which was deposited at 350°C with 0.26 g of SbCl3 and 4 g of SnCl4 (SbCl3/SnCl4 = 0.065).
Evaporated films were found to be amorphous in the temperature range up to 200°C, whereas spray pyrolyzed films prepared at
substrate temperature of 300– 370°C were poly crystalline. The morphology of tin oxide films was studied using SEM. 相似文献
4.
Jinhua Huang Ruiqin Tan Yulong Zhang Jia Li Ye Yang Xianpeng Zhang Weijie Song 《Journal of Materials Science: Materials in Electronics》2012,23(2):356-360
In this work, Al-doped (4 at%) ZnO(AZO) thin films were prepared by DC magnetron sputtering using a home-made ceramic target
at different substrate temperatures. The microstructure, optical, electrical and thermal stability properties of these thin
films were characterized systematically using scanning electron microscopy, UV–Vis-NIR spectrometry, X-ray diffraction, and
Hall measurements. It was observed that the AZO thin films deposited at 350 °C exhibited the lowest resistivity of 5.76 × 10−4 Ω cm, high average visible transmittance (400–800 nm) of 92%, and the best thermal stability. Comparing with the AZO thin
films deposited at low substrate temperatures, the AZO thin films deposited at 350 °C had the highest compact surface morphology
which could hinder the chemisorbed and diffused oxygen. This was considered to be the main mechanism which was responsible
for the thermal degradation of AZO thin films. 相似文献
5.
D. K. Dwivedi Vipin Kumar M. Dubey H. P. Pathak 《Journal of Materials Science: Materials in Electronics》2012,23(3):675-680
Cd1−xZnxTe (where x = 0.02, 0.04, 0.06, 0.08) thin film have been deposited on glass substrate at room temperature by thermal evaporation
technique in a vacuum at 2 × 10−5 torr. The structural analysis of the films has been investigated using X-ray diffraction technique. The scanning electron
microscopy has been employed to know the morphology behaviour of the thin films. The temperature dependence of DC electrical
conductivity has been studied. In low temperature range the thermal activation energy corresponding to the grain boundary—limited
conduction are found to be in the range of 38–48 μeV, but in the high temperature range the activation energy varies between
86 and 1.01 meV. The built in voltage, the width of the depletion region and the operating conduction mechanism have been
determined from dark current voltage (I–V) and capacitor-voltage (C–V) characteristics of Cd1−xZnxTe thin films. 相似文献
6.
In this study, polycrystalline AgGaS2 thin films were deposited by the sequential evaporation of AgGaS2 and Ag sources with thermal evaporation technique. Thermal treatment in nitrogen atmosphere for 5 min up to 700 °C was applied
to the deposited thin films and that resulted in the mono phase AgGaS2 thin films without the participation of any other minor phase. Structural and compositional analyses showed the structure
of the films completely changes with annealing process. The measurements of transmittance and reflectance allowed us to calculate
the band gap of films lying in 2.65 and 2.79 eV depending on annealing temperature. The changes in the structure with annealing
process also modify the electrical properties of the films. The resistivity of the samples varied in between 2 × 103 and 9 × 106 (Ω-cm). The room temperature mobility depending on the increasing annealing temperature was in the range of 6.7–37 (cm2 V−1 s−1) with the changes in carrier concentrations lying in 5.7 × 1013–2.5 × 1010 cm−3. Mobility-temperature dependence was also analyzed to determine the scattering mechanisms in the studied temperature range
with annealing. The variations in the electrical parameters of the films were discussed in terms of their structural changes. 相似文献
7.
Daniel S. Likius Hiroki Nagai Sohei Aoyama Chihiro Mochizuki Hiroki Hara Norio Baba Mitsunobu Sato 《Journal of Materials Science》2012,47(8):3890-3899
To find the percolation threshold for the electrical resistivity of metallic Ag-nanoparticle/titania composite thin films,
Ag-NP/titania composite thin films, with different volumetric fractions of silver (0.26 ≤ φAg ≤ 0.68) to titania, were fabricated on a quartz glass substrate at 600 °C using the molecular precursor method. Respective
precursor solutions for Ag-nanoparticles and titania were prepared from Ag salt and a titanium complex. The resistivity of
the films was of the order of 10−2 to 10−5 Ω cm with film thicknesses in the range 100–260 nm. The percolation threshold was identified at a φAg value of 0.30. The lowest electrical resistivity of 10−5 Ω cm at 25 °C was recorded for the composite with the Ag fraction, φAg, of 0.55. X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), and transmission electron microscopic
(TEM) evaluation of the effect of the morphology and the nanostructures of the Ag nanoparticles in the composite thin films
on the electrical resistivity of the film revealed that the films consist of rutile, anatase, and metallic Ag nanoparticles
homogeneously distributed in the titania matrix. It could be deduced that the electrical resistivity of the thin films formed
at 600 °C was unaffected by the anatase/rutile content within the thin film, whereas the shape, size, and separation distance
of the Ag nanoparticles strongly influenced the electrical resistivity of the Ag-nanoparticle/titania composite thin films. 相似文献
8.
B. T. Raut P. R. Godse S. G. Pawar M. A. Chougule V. B. Patil 《Journal of Materials Science: Materials in Electronics》2012,23(4):956-963
In the present work, we report on the performance of a nanostructured CdS gas sensor. The sensor was fabricated using spin
coating technique on glass substrate. The CdS sensor was characterized for their, structural microstructural as well as optoelectronic
and H2S response was studied. The XRD analysis showed formation of nanocrystalline CdS. Morphological analysis using SEM revealed
nanostructured morphology with average grain size in the range of 40–50nm. Optical investigations showed a high absorption
coefficient (104 cm−1) with a direct band gap of 2.54 eV. Electrical transport studies revealed films shows n-type conduction mechanism with room
temperature dc electrical conductivity 10−6 (Ω cm)−1. The CdS sensors showed the maximum response of 13.2% upon exposure to 100 ppm H2S at operating temperature 100 °C. 相似文献
9.
M. A. Chougule S. G. Pawar P. R. Godse R. D. Sakhare Shashwati Sen V. B. Patil 《Journal of Materials Science: Materials in Electronics》2012,23(3):772-778
Nanocrystalline Co3O4 thin films were prepared on glass substrates by using sol–gel spin coating technique. The effect of annealing temperature
(400–700 °C) on structural, morphological, electrical and optical properties of Co3O4 thin films were studied by X-ray diffraction (XRD), Scanning Electron Microscopy, Electrical conductivity and UV–visible
Spectroscopy. XRD measurements show that all the films are nanocrystallized in the cubic spinel structure and present a random
orientation. The crystallite size increases with increasing annealing temperature (53–69 nm). These modifications influence
the optical properties. The morphology of the sol–gel derived Co3O4 shows nanocrystalline grains with some overgrown clusters and it varies with annealing temperature. The optical band gap
has been determined from the absorption coefficient. We found that the optical band gap energy decreases from 2.58 to 2.07 eV
with increasing annealing temperature between 400 and 700 °C. These mean that the optical quality of Co3O4 films is improved by annealing. The dc electrical conductivity of Co3O4 thin films were increased from 10−4 to 10−2 (Ω cm)−1 with increase in annealing temperature. The electron carrier concentration (n) and mobility (μ) of Co3O4 films annealed at 400–700 °C were estimated to be of the order of 2.4–4.5 × 1019 cm−3 and 5.2–7.0 × 10−5 cm2 V−1 s−1 respectively. It is observed that Co3O4 thin film annealing at 700 °C after deposition provide a smooth and flat texture suited for optoelectronic applications. 相似文献
10.
Changgang Huang Meili Wang Zhonghua Deng Yongge Cao Quanlin Liu Zhi Huang Yuan Liu Wang Guo Qiufeng Huang 《Journal of Materials Science: Materials in Electronics》2010,21(11):1221-1227
Indium-doped zinc oxide (IZO) films were fabricated by radio-frequency magnetron sputtering. The effects of hydrogen annealing
on the structural, optical and electrical properties of the IZO films were investigated. The hydrogen annealing may deteriorate
the crystallinity of the films. The surfaces of the films would be damaged when the annealing temperature was higher than
350 °C. After the annealing, the surface roughness of the films would decrease, and high transparency of 80–90% in the visible
and near-infrared wavelength would be kept. Meanwhile, the resistivity decreased from 1.25 × 10−3 Ωcm of the deposited films to 6.70 × 10−4 Ωcm of the annealed films. The work function of the IZO films may be modulated between 4.6 and 4.98 eV by varying the hydrogen
annealing temperature and duration. 相似文献
11.
High quality heteroepitaxial thin films of ZnO:N were grown by pulsed laser deposition using a two-step growth method and
annealed in situ at different temperatures and ambient conditions. Films were analyzed by X-ray diffraction (XRD), electrical
measurements, and photoluminescence experiments at low temperatures to investigate the effect of nitrogen doping. The XRD
results demonstrate epitaxial growth on the c-sapphire substrates, with average grain size of 57 nm. Photoluminescence spectra
reveals a peak at 3.061 eV (405.1 nm) which is part of the longitudinal-optical-phonon replicas of excitons bound to neutral
acceptors
\textA10 \textX\textA {\text{A}}_{1}^{0} \,{\text{X}}_{\text{A}} at 3.348 eV (370.4 nm), attributed in recent investigations to a newly reported donor–acceptor pair. Electrical resistivity
and Hall effect measurements were performed using standard four point van der Pauw geometry at room temperature. Fresh films
exhibited a resistivity of 3.1 × 10−3 Ω cm, a carrier density of 1.3 × 1019 cm−3, and a mobility of 53 cm2/V s. During approximately 2 weeks the as-deposited films presented a p-type behavior, as shown by the positive sign of the
Hall constant measured. Thereafter, films reverted to n-type. From electrical measurements and photoluminescence spectra,
the acceptor energy was determined to be 150 meV, in close agreement with reported values. These results are consistent with
those presented in the literature for high purity crystals or homoepitaxial thin films, even though samples for the present
study were processed at lower annealing temperature. 相似文献
12.
Y. Kumashiro K. Nakamura T. Enomoto M. Tanaka 《Journal of Materials Science: Materials in Electronics》2011,22(8):966-973
The chemical vapor deposited (CVD) BP films on Si(100) (190 nm)/SiO
x
(370 nm)/Si(100) (625 μm) (SOI) and sapphire (R-plane) (600 μm) substrates were prepared by the thermal decomposition of
the B2H6–PH3–H2 system in the temperature range of 800–1050 °C for the deposition time of 1.5 h. The BP films were epitaxially grown on the
SOI substrate, but a two-step growth method, i.e., a buffer layer at lower temperature and sequent CVD process at 1000 °C
for 1.5 h was effective for obtaining a smooth film on the sapphire substrate. The electrical conduction types and electrical
properties of these films depended on the growth temperature, gases flow rates and substrates. The thermal conductivity of
the film could be replaced by the substrate, so that the calculated thermoelectric figure-of-merit (Z) for the BP films on the SOI substrate was 10−4–10−3/K at 700–1000 K. Those on the sapphire substrate were 10−6–10−5/K for the direct growth and 10−5–10−4/K for the two-step growth at 700–900 K, indicating that the film on a sapphire by two-step growth would reduce the defect
concentrations and promote the electrical conductivity. 相似文献
13.
When titanium/silicon-dioxide (Ti/SiO2) structures prepared by depositing titanium (Ti) on thermally oxidized silicon in vacuum were heated to temperatures of 800–1000°C
in flowing oxygen gas, silicon surfaces were covered with a mixture films containing preferentially (110)-oriented Ti02 instead of the SiO2 films. The thickness of the mixture films could be determined by that of the deposited Ti films. Titanium silicide grew only
in the region near between the grown mixture film and the silicon substrate. The dielectric constants of the grown mixture
films increased exponentially with increasing oxidation temperature and increased slowly with increasing the Ti film thickness,
while the breakdown field strength increased slowly with increasing oxidation temperature and increased exponentially with
increasing the Ti film thickness. The oxide films prepared at 1000°C had dielectric constants of (15–25)ɛo resistivities of 1010–1011 Ω cm, and breakdown field strengths of about 106 V/cm.
Received: 10 February 1998 / Accepted: 10 March 1998 相似文献
14.
V. Gokulakrishnan S. Parthiban K. Jeganathan K. Ramamurthi 《Journal of Materials Science》2011,46(16):5553-5558
Niobium-doped tin oxide thin films were deposited on glass substrates by the chemical spray pyrolysis method at a substrate
temperature of 400 °C. Effects of Nb doping on the structural, electrical and optical properties have been investigated as
a function of niobium concentration (0–2 at.%) in the spray solution. X-ray diffraction patterns showed that the films are
polycrystalline in nature and the preferred growth direction of the undoped film shifts to (200) for Nb-doped films. Atomic
force microscopy study shows that the surface morphology of these films vary when doping concentration varies. The negative
sign of Hall coefficient confirmed the n-type conductivity. Resistivity of ~4.3 × 10−3 Ω cm, carrier concentration of ~5 × 1019 cm−3, mobility of ~25 cm2 V−1 s−1 and an average optical transmittance of ~70% in the visible region (500–800 nm) were obtained for the film doped with 0.5 at.%
niobium. 相似文献
15.
Structural, optical, and electric properties of BNT–BT0.08 thin films processed by sol–gel technique
Marin Cernea Lucian Trupina Cristina Dragoi Aurelian-Catalin Galca Liliana Trinca 《Journal of Materials Science》2012,47(19):6966-6971
Thin films with the composition [(Bi0.5Na0.5)TiO3]0.92–[BaTiO3]0.08 (hereafter BNT–BT0.08) were deposited on Pt–Si by spin-coating from a stable sol precursor. The BNT–BT0.08 film, crystallized on the Bi0.5Na0.5TiO3 rhombohedral lattice, was obtained after annealing the film-gel at 700 °C. The films have a smooth surface (Rms = 2.76 nm) and grains with ferroelectric domains. The film showed a bandgap of 3.25 eV and a refractive index of 2.20 at a wavelength of 630 nm. The dielectric characteristics of BNT–BT0.08 thin films were measured at room temperature and 10 kHz the dielectric constant (ε r) was 243 and the loss tangent (tanδ) was 0.38. The remnant polarization (P r) was 0.87 μC/cm2 and the coercive field (E c) was 220 kV/cm at 10 kHz and room temperature. The current density was approximately 2.7 × 10−5 A/cm2 at low electric fields (100 kV/cm). BNT–BT0.08 thin films shown piezoelectric properties (d 33eff = 100 pm/V) comparable to those of PZT thin films. 相似文献
16.
N. M. Shah J. R. Ray V. A. Kheraj M. S. Desai C. J. Panchal Bharti Rehani 《Journal of Materials Science》2009,44(1):316-322
Copper indium diselenide (CuInSe2) compound was synthesized by reacting its elemental components, i.e., copper, indium, and selenium, in stoichiometric proportions
(i.e., 1:1:2 with 5% excess selenium) in an evacuated quartz ampoule. Structural and compositional characterization of synthesized
pulverized material confirms the polycrystalline nature of tetragonal phase and stoichiometry. CuInSe2 thin films were deposited on soda lime glass substrates kept at different temperatures (300–573 K) using flash evaporation
technique. The effect of substrate temperature on structural, morphological, optical, and electrical properties of CuInSe2 thin films were investigated using X-ray diffraction analysis (XRD), atomic force microscopy (AFM), optical measurements
(transmission and reflection), and Hall effect characterization techniques. XRD analysis revealed that CuInSe2 thin films deposited above 473 K exhibit (112) preferred orientation of grains. Transmission and reflectance measurements
analysis suggests that CuInSe2 thin films deposited at different substrate temperatures have high absorption coefficient (~104 cm−1) and optical energy band gap in the range 0.93–1.02 eV. Results of electrical characterization showed that CuInSe2 thin films deposited at different substrate temperatures have p-type conductivity and hole mobility value in the range 19–136 cm2/Vs. Variation of energy band gap and resistivity of CuInSe2 thin films deposited at 523 K with thickness was also studied. The temperature dependence of electrical conductivity measurements
showed that CuInSe2 film deposited at 523 K has an activation energy of ~30 meV. 相似文献
17.
The present work deals with the mixing of iron and silicon by swift heavy ions in high-energy range. The thin film was deposited
on a n-Si (111) substrate at 10−6 torr and at room temperature. Irradiations were undertaken at room temperature using 120 MeV Au+9 ions at the Fe/Si interface to investigate ion beam mixing at various doses: 5 × 1012 and 5 × 1013 ions/cm2. Formation of different phases of iron silicide has been investigated by X-ray diffraction (XRD) technique, which shows enhancement
of intermixing and silicide formation as a result of irradiation. I-V measurements for both pristine and irradiated samples have been carried out at room temperature, series resistance and barrier
heights for both as deposited and irradiated samples were extracted. The barrier height was found to vary from 0·73–0·54 eV.
The series resistance varied from 102·04–38·61 kΩ. 相似文献
18.
C. Aguzzoli C. A. Figueroa G. V. Soares I. J. R. Baumvol 《Journal of Materials Science》2010,45(18):4994-5001
Vanadium carbide and titanium carbide films were deposited on Si substrates by direct current reactive magnetron sputtering,
varying the substrate temperature during deposition and the reactive gas (CH4) pressure. The physicochemical and structural properties of the films were characterized for stoichiometric films (V/C = 1
and Ti/C = 1), which display good performance concerning wear, friction, and corrosion. The techniques used to characterize
the films were Rutherford backscattering spectrometry in channeling geometry, 12C(α,α)12C nuclear resonant scattering, glancing angle X-ray diffraction, X-ray reflectometry, and X-ray photoelectron spectroscopy.
The results revealed that the ideal conditions for deposition of these films are a CH4 partial pressure of 0.5 × 10−3 mbar and a substrate temperature of 400 °C. In such conditions, the deposition rates are 7 nm s−1 for TiC and 8.5 nm s−1 for VC at a target power density of 5.5 W cm−2. The density of the films, as determined here by X-ray reflectometry, are slightly higher than those for the bulk materials. 相似文献
19.
Thin films of molybdenum oxide were formed on glass and silicon substrates by sputtering of molybdenum target under various
sputtering powers in the range 2.3–6.8 W/cm2, at a constant oxygen partial pressure of 2 × 10−4 mbar and substrate temperature 523 K employing DC magnetron sputtering technique. The effect of sputtering power on the core
level binding energies, chemical binding configurations, crystallographic structure, surface morphology and electrical and
optical properties was systematically studied. X-ray photoelectron spectroscopic studies revealed that the films formed at
sputtering powers less than 5.7 W/cm2 were mixed oxidation states of Mo5+ and Mo6+. The films formed at 5.7 W/cm2 contained the oxidation state Mo6+ of MoO3. Fourier transform infrared spectra contained the characteristic optical vibrations. The presence of a sharp absorption band
at 1,000 cm−1 in the case of the films formed at 5.7 W/cm2 was also conformed the existence of α-phase MoO3. X-ray diffraction studies also confirmed that the films formed at sputtering powers less than 5.7 W/cm2 showed the mixed phase of α-and β-phase of MoO3 where as at sputtering power of 5.7 W/cm2 showed single phase α-MoO3. The electrical conductivity of the films increased from 8 × 10−6 to 1.2 × 10−4 Ω−1 cm−1, the optical band gap decreased from 3.28 to 3.12 eV and the refractive index decreased from 2.12 to 1.94 with the increase
of sputtering power from 2.3 to 6.8 W/cm2, respectively. 相似文献
20.
C. C. Yu M. C. Kao H. Z. Chen S. L. Young C. H. Lin 《Journal of Superconductivity and Novel Magnetism》2010,23(6):929-932
Bi3.2Gd0.8Ti3O12 (BGTO) thin films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates using the sol-gel method and rapid thermal annealing in an oxygen atmosphere. The effects of annealing
temperature (500–800°C) on microstructure and electrical properties of thin films were investigated. X-ray diffraction analysis
shows that the BGT thin films have a bismuth-layered perovskite structure with preferred (117) orientation. The intensities
of (117) peaks increases with increasing annealing temperature. The leakage current density (J) was 3.69×10−8 A/cm2 at 200 kV/cm. It was found that the leakage current was affected not only by the microstructure but also by the interface
between the Pt electrode and BGTO thin films. In the low electric field region, the leakage current was controlled by Poole–Frenkel
emission. In addition, the mechanism can be explained by Schottky emission from the Pt electrode in the high electric field
region. 相似文献