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1.
Wen-Ching Shih Ming-Han Chiang 《Journal of Materials Science: Materials in Electronics》2010,21(8):844-848
In this paper, BaTiO3 thin films were prepared by RF magnetron sputtering on MgO substrates and their properties such as the crystal structure
and optical waveguide properties were investigated. The optimum deposition parameters, such as substrate temperature, deposition
pressure, gas flow ratio, the RF power and the after annealing temperature, were obtained in order to get the best BaTiO3 film quality. The XRD results show that highly c-axis textured BaTiO3 thin films were successfully grown on MgO substrate. Films obtained under the optimum deposition parameters, substrate temperature
of 650°C, RF power of 50 W, deposition pressure 18 mTorr and gas flow ratio O2/(Ar+ O2) of 15% namely, reaches a full width at half maximum intensity (FWHM) of BaTiO3 (002) XRD peak of 0.25°. The FWHM of BaTiO3 (002) XRD peak was further reduced to 0.24° via post-treatment with furnace annealing (at 800°C for 2 h) which indicates
the film crystal quality is further improved. The bright and sharp TE modes measured by m-line spectroscopy of the BaTiO3 film were observed indicating its possible application in optical waveguide. 相似文献
2.
Min-Chun Pan Tzon-Han Wu Tuan-Anh Bui Wen-Ching Shih 《Journal of Materials Science: Materials in Electronics》2012,23(2):418-424
The influence of fabrication parameters on ZnO film properties has been analyzed through conducting several experiment processes
to develop an appropriate deposition condition for obtaining highly c-axis textured films. A transducer with the structure of Al/ZnO/Al/Si was fabricated at low deposition rate and under a temperature
of 380 °C in a mixture of gases Ar:O2 = 1:3, and RF power of 178 W. Pt/Ti was employed as the bottom electrode of the transducer fabricated in a suitable substrate
temperature, which starts increasing at 380 °C with an increment of 20 °C for each 2 h stage of the deposition. Highly c-axis textured ZnO films have been successfully deposited on Pt/Ti/SiO2/Si substrate under feasible conditions, including RF power of 178 W, substrate temperature of 380 °C, deposition pressure
of 1.3 Pa and Ar:O2 gas flow ratio of 50%. These conditions have been proposed and confirmed through investigating the influences of the sputtering
parameters, such as substrate temperature, RF power and Ar:O2 gas flow ratio, on the properties of ZnO films. 相似文献
3.
Barium titanate (BaTiO3) thin films prepared on magnesia, silicon and strontium titanate substrates by r.f. sputtering has been investigated. As a function of substrate and annealing temperatures, the crystal structure and shape were examined by X-ray diffraction and scanning electron microscopy. Thin films were grown on both MgO and silicon substrates; they were amorphous when deposited on MgO if the substrate temperature was less than 450 °C, while for those grown on silicon the temperature had to be less than 500 °C. Above these elevated temperatures, the films were crystalline, with cubic symmetry. After annealing the thin films on magnesia, the crystal structure changed from cubic to tetragonal phase above 1100 °C; thebe c-axis or annealing thus caused the grain growth of the BaTiO3. The thin films on SrTiO3 were found toc-axis oriented tetragonal films for a substrate temperature above 500 °C. 相似文献
4.
Qiang Luo Linfei Liu Guina Xiao Yijie Li 《Journal of Superconductivity and Novel Magnetism》2014,27(6):1419-1424
We deposited epi-MgO films on the textured ion beam assisted deposition (IBAD)-MgO substrates by RF magnetic sputtering at different substrate temperatures (600–850 °C), RF powers (110–224 W) and oxygen partial pressures (19.5–58.6 mTorr). The microstructure and surface morphology of epi-MgO films were characterized by X-ray diffraction (XRD) and atom force microscope (AFM). It was found that epi-MgO films with c-axis orientation could be easily fabricated for broad parameter ranges. But the in-plane full width half maximum (FWHM) of the epi-MgO film was dependent on the parameters, and the epi-MgO film with the smallest FWHM value of 5.22° was obtained at the optimum parameters. What’s more, the GdBa2Cu3O7 films deposited on the epi-MgO/IBAD-MgO substrate by RF magnetic sputtering showed c-axis orientation. 相似文献
5.
High epitaxial quality BaTiO3 films were deposited on the MgO (001) substrate using RF magnetron sputtering at 800 °C by manipulating processing parameters. The BaTiO3 films have a ~200 nm thickness with a very low surface roughness but a rough interface structure with respect to the substrate. The epitaxial BaTiO3 films have a tetragonal crystal structure (a = 4.02 Å and c = 4.11 Å) with a tetragonality (c/a) of 1.02. The c-axis of the film is parallel to the growth direction as characterized by X-ray diffraction, electron diffraction, and high-resolution transmission electron microscopy. The orientation relationship between the film and the MgO is (001)BTO//(001)MgO and 〈100〉BTO//〈100〉MgO. Epitaxial nanodomains were formed in the film with a size ranging from 3 to 20 nm. The formation of the nanodomains is associated with the rough film/substrate interface due to the modification of the substrate surface characteristics (steps, terraces, and kinks) during the process. The two-dimensional interface structure between the film and the substrate was studied and its influence on the film microstructure is discussed. 相似文献
6.
《Materials Letters》2007,61(4-5):1052-1055
High-quality single-phase, c-axis textured LiTaO3 thin films have been deposited on Si(100) substrate with amorphous SiO2 buffer layer for optic waveguide application by pulsed laser deposition under optimized conditions of 30 Pa oxygen pressure and 650 °C. The amorphous SiO2 buffer layer with a thickness of 100 nm was coated on the Si(100) by thermal oxidation at 1000 °C. Li-enriched LiTaO3 ceramic target was used during the deposition. In order to study the influence of oxygen pressure on the orientation, crystallinity and morphology, different oxygen pressures (10 Pa, 20 Pa, 30 Pa and 40 Pa) were used. X-ray diffraction (XRD) results showed that LiTaO3 thin films exhibited highly c-axis orientation under 30 Pa. It was observed by scanning electron microscopy (SEM) that the as-grown film in the optimal conditions was characterized by a dense and homogeneous surface without cracks, and the average grain size was in the order of 25 nm. 相似文献
7.
Yu-Hsiang Hsu John Lin William C. Tang 《Journal of Materials Science: Materials in Electronics》2008,19(7):653-661
This paper demonstrates the substrate dependency of the c-axis zinc oxide growth in radio-frequency sputtering system. Different deposition conditions were designed to study the influences
of Si, SiO2/Si, Au/Ti/Si, and Au/Ti/SiO2/Si substrates on the piezoelectric and crystalline qualities of the ZnO thin films. Experimental results showed that the
multilayer of Au/Ti/SiO2/Si-coated silicon substrate provided a surface that facilitated the growth of ZnO thin film with the most preferred crystalline
orientation. The 1.5 μm-thick thermally grown amorphous silicon dioxide layer effectively masked the crystalline surface of
the silicon substrate, thus allowing the depositions of high-quality 20 nm-thick titanium adhesion layer followed by 150 nm-thick
of gold thin film. The gold-coated surface allowed deposition of highly columnar ZnO polycrystalline structures. It was also
demonstrated that by lowering the deposition rate at the start of sputtering by lowering RF power to less than one-third of
the targeted RF power, a fine ZnO seed layer could be created for subsequent higher-rate deposition. This two-step deposition
method resulted in substantially enhanced ZnO film quality compared to single-step approach. The influence of stress relaxation
by annealing was also investigated and was found to be effective in releasing most of the residual stress in this layered
structure. 相似文献
8.
We report the growth of highly C-axis orientation of Sr
x
Ba1−x
Nb2O6 (SBN) thin films on p-type (100) Si substrates by using a potassium-substituted SBN template layer with the sol–gel method. The crystallization of SBN thin films was found closely related to the potassium ion doping concentration and the postannealing temperature of the K-SBN template layer. Secondary ion mass spectrometry analysis showed that potassium elements were accumulated at the interface of the template layer and silicon substrate. SBN films postannealed at 750 °C with K-SBN template layer has a smaller full width at half maximum of X-ray rocking curve of 2.45° than that of 5.40° for the pure SBN films. By introducing a template layer, the surface morphologies of SBN films fabricated on silicon substrate were greatly improved. 相似文献
9.
Solid phase technology of growing of epitaxial and textured Mg2Si films on Si(111) is developed. It includes fabrication of template layer, deposition of multiplayer sandwich structure Mg/Si/ and final annealing. Research results are presented on morphology, structure and optical properties of thin Mg2Si films grown on Si(111) by the method of solid-phase annealing on a template layer. 相似文献
10.
H. Z. Chen M. C. Kao S. L. Young C. C. Yu C. H. Lin C. R. Ou C. M. Lee 《Journal of Superconductivity and Novel Magnetism》2010,23(6):933-935
Bi4Ti3.96Nb0.04O12 thin films were successfully deposited on Pt(111)/Ti/SiO2/Si(100) substrates by a sol–gel method and rapid thermal annealing. The effects of Nb-substitution and annealing temperature
(500–800°C) on the microstructure and ferroelectric properties of bismuth titanate thin films were investigated. X-ray diffraction
analysis reveals that the intensities of (117) peaks are relatively broad and weak at annealing temperatures smaller than
700°C. With the increase of annealing temperature from 500°C to 800°C, the grain size of Bi4Ti3.96Nb0.04O12 thin films increases. The Bi4Ti3.96Nb0.04O12 thin films annealed at 700°C exhibit the highest remanent polarization (2P
r), 36 μC/cm2 and lowest coercive field (2E
c), 110 kV/cm. The improved ferroelectric properties can be attributed to the substitution of Nb5+ to Ti4+ in Bi4Ti3O12 assisting the elimination of defects such as oxygen vacancy and vacancy complexes. 相似文献
11.
《Materials Science and Engineering: B》2001,79(1):86-89
Relationship between the crystallographic orientation and the electrical properties of the Pb(Zr,Ti)O3, (PZT) thin films prepared by rf magnetron sputtering was investigated. The PZT films were deposited at 150, 250 or 340°C and, followed by rapid thermal annealing (RTA). It was found that the crystallographic orientation of the PZT films could be controlled only by the deposition temperature and the ferroelectric properties were dependent upon the orientation of the films. It was suggested that the difference in the atomic mobility at the substrate surface during deposition was closely related to the film orientation. The films with (111) orientation showed relatively high capacitance and the remanant polarization values. 相似文献
12.
Shadi Al-Khateeb D. Pavlopoulos T. W. Button J. S. Abell 《Journal of Superconductivity and Novel Magnetism》2013,26(2):273-280
Spray pyrolysis was used to deposit MgO films on polycrystalline 321-austentic stainless steel substrates using magnesium nitrates and magnesium acetates as precursors. The MgO films deposited from the nitrate precursors were amorphous; however, MgO (200) oriented films were obtained when the acetates precursors were used. The texture of the films was improved with increasing the concentration and the deposition temperature. To evaluate the performance of the MgO buffers, PLD was used to deposit YBCO on MgO-buffered 321 substrates. Only the smoothest MgO films were found as good buffers for the deposition of c-axis oriented YBCO films. The superconducting transition temperature was broad and the T C onset was 83.6 K. Austenitic 321 steel is an alternative for C276 as a substrate for thin film deposition. 相似文献
13.
《Materials Letters》2005,59(24-25):2994-2997
Highly c-axis oriented LiNbO3 thin films have been deposited on Si (111) substrates by pulsed laser deposition. A stoichiometric sintered LiNbO3 is used as the target. The c-axis orientation and stoichiometry of LiNbO3 films are strongly influenced by substrate temperature and oxygen pressure. The substrate temperature 600 °C and oxygen pressure 20–30 Pa are found to be optimized parameters for the growth of textured film. The results showed that the size and the density of droplets decreased with increasing substrate temperature, and droplets would disappear when substrate temperature is increased above 600 °C. The surface microstructures of LiNbO3 films under optimized conditions are fine, uniform and dense. The AFM images ensured that the as-grown films are good enough to be integrated with the semiconductor devices. 相似文献
14.
Various crystallization parameters were studied during the fabrication of Bi3.15Nd0.85Ti3O12 (BNdT) thin films on Pt/Ti/SiO2/Si (100) by metal organic solution decomposition method. The effect of crystallization processes, crystallization ambients on the properties of BNdT thin films such as orientation, ferroelectric properties were examined. By adopting different fabrication processes, it is possible to get both highly c-axis oriented as well as randomly oriented thin films. Highly c-axis oriented BNdT thin film showed a large remnant polarization (2Pr) of 70 μC/cm2 at an applied voltage of 10 V and exhibited a fatigue free behavior unto 2 × 109 switching cycles. The improved ferroelectric properties of BNdT thin films suggest their suitability for high density ferroelectric random access memory applications. 相似文献
15.
This work analyzes the effect of post-deposition rapid thermal annealing (RTA) on the crystal quality and the piezoelectric response of sputtered polycrystalline aluminium nitride (AlN) thin films. AlN films with mixed crystal texture were not significantly affected by RTA processing. However, in films exhibiting clear c-axis preferred orientation, the annealing produced a crystallization process, characterized by an increase in the grain size of the original crystallites, the growth of new small grains, and the reduction of defects. The improvement in the crystal quality was more evident in highly textured c-axis oriented films. However, the enhanced crystal quality of the films due to RTA was not accompanied by a significant improvement in the piezoelectric response. This is attributed to the presence of grains with opposite polarities that could not be rearranged through the RTA treatment. 相似文献
16.
《Thin solid films》2006,494(1-2):240-243
We have investigated the influence of N2 addition to the Ar sputtering gas on the crystal orientation of sputtered Ru films. An rf magnetron sputtering apparatus with a Ru target (99.9%) and a glass substrate heated to 100 °C or 300 °C was used for the deposition. The crystal structure, chemical composition and electrical properties of the resultant films were investigated. X-ray diffraction (XRD) revealed the dominant orientation at 0% N2 to be the c-axis. With increasing proportion of N2 in the sputtering gas at a substrate temperature of 100 °C, the intensity of the (002) peak decreased, finally disappearing at 50% N2. This c-axis-suppressed Ru film sputtered at 50% N2 was found to contain nitrogen by Auger electron spectroscopy (AES), but by annealing the film in vacuum at 400 °C, the nitrogen in the film was completely removed. The film orientation remained the same as before annealing. Thus, we have demonstrated a new method for depositing Ru films with a controlled preferential orientation of either c-axis oriented or c-axis suppressed. 相似文献
17.
Zhitao Zhou Fengjiao Shang Guangcai Pan Feng Wang Changlong Liu Wanbing Gong Zhenfa Zi Yiyong Wei Jianguo Lv Xiaoshuang Chen Gang He Miao Zhang Xueping Song Zhaoqi Sun 《Journal of Materials Science: Materials in Electronics》2014,25(5):2053-2059
Mg0.05Zn0.95O thin films were prepared on silicon substrates by a sol–gel dip-coating technique. Microstructure, surface topography and optical properties of the thin films were characterized by X-ray diffraction, atom force microscopy, Fourier transform infrared spectrophotometer and fluorescence spectrometer. The results show that the thin film annealed at 700 °C has the largest average grain size and exhibits the best c-axis preferred orientation. As annealing temperature increases to 800 °C, the grain along c-axis has been suppressed. Roughness factor and average particle size increase with the increase of annealing temperature. The IR absorption peak appearing at about 416 cm?1 is assigned to hexagonal wurtzite ZnO. The thin film annealed at 700 °C has the maximum oxygen vacancy, which can be inferred from the green emission intensity. Photocatalytic results show that the thin film annealed at 700 °C exhibits remarkable photocatalytic activity, which may be attributed to the larger grain size, roughness factor and concentration of oxygen vacancy. Enhanced photocatalytic activity of Mg0.05Zn0.95O thin films after a cycle may be attributed to the increase of surface oxygen vacancy and photocorrosion of amorphous MgO on the surface of thin film under UV irradiation. 相似文献
18.
《Materials Letters》2004,58(12-13):1885-1888
Barium metaplumbate (BaPbO3, BPO) thin films were prepared on Pt/Ti/SiO2/Si substrates by a sol–gel method and a rapid thermal annealing (RTA) process. X-ray diffraction (XRD) was used to characterize the crystalline structure of the resultant films. It was shown that the formation of perovskite BPO greatly depends on the lead concentration and the final annealing temperature. In terms of the semi-quantitative energy dispersion spectrum (EDS) analysis, the ratio of Pb/Ba in the BPO ceramic films increases as the final heating temperature increases. Using BPO as buffer layers, PZT thin films with a pure perovskite structure were grown at a very low temperature of 500 °C by the sol–gel technique and the RTA process. The remanent polarization of Pt/PZT/BPO/Pt ferroelectric capacitors is about 17 μC/cm2 at an applied voltage of 3 V. 相似文献
19.
In order to get good quality reproducible films of Tl : HTSC system, we have studied the different annealing conditions to
finally achieve the optimized annealing condition. In the present investigation, Tl-Ca-Ba-Cu-O superconducting films have
been prepared on YSZ (100) and MgO (100) single crystal substrates via precursor route followed by thallination. The post
deposition heat treatments of the precursor films were carried out for various annealing temperatures (870°C, 890°C) and durations
(1 and 2 min). The optimized thallination procedure occurred at 870°C for 2 min into good quality films withT
c (R = 0) ∼ 103 K for YSZ andT
c (R = 0) ∼ 98 K for MgO substrates, respectively. Further we have correlated the structural/microstructural characteristics of
the films. 相似文献
20.
Pb(Zr0.53Ti0.47)O3 (PZT) thin films were prepared on Pt/Ti/SiO2/Si substrate by sol–gel method. The effect of annealing temperature on microstructure, ferroelectric and dielectric properties
of PZT films was investigated. When the films were annealed at 550–850 °C, the single-phase PZT films were obtained. PZT films
annealed at 650–750 °C had better dielectric and ferroelectric properties. The sandwich composites with epoxy resin/PZT film
with substrate/epoxy resin were prepared. The annealing temperature of PZT films influenced their damping properties, and
the epoxy-based composites embedded with PZT film annealed at 700 °C had the largest damping loss factor of 0.923. 相似文献