Sol-Gel derived Bi4-xNdxTi3O12 Thin Films and Their Characterization

2002 ◽  
Vol 737 ◽  
Author(s):  
R.E. Melgarejo ◽  
M.S. Tomar ◽  
A. Hidalgo ◽  
R.S. Katiyar

ABSTRACTNd substituted bismuth titanate Bi4-xNdxTi3O12 were synthesized by sol-gel process and thin films were deposited on Pt substrate (Pt/TiO2/SiO2/Si) by spin coating. Thin films, characterized by X-ray diffraction and Raman spectroscopy, shows complete solid solution up to the composition x < 1. Initial results indicate that the ferroelectric polarization increases with increasing Nd content in the film with 2Pr = 50μC/cm2 for x = 0.46, which may have application in non-volatile ferroelectric memory devices.

2010 ◽  
Vol 93-94 ◽  
pp. 231-234
Author(s):  
B. Hongthong ◽  
Satreerat K. Hodak ◽  
Sukkaneste Tungasmita

Strontium substituted hydroxyapatite(SrHAp) were fabricated both in the form of powder as reference and thin film by using inorganic precursor reaction. The sol-gel process has been used for the deposition of SrHAp layer on stainless steal 316L substrate by spin coating technique, after that the films were annealed in air at various temperatures. The chemical composition of SrHAp is represented (SrxCa1-x)5(PO4)3OH, where x is equal to 0, 0.5 and 1.0. Investigations of the phase structure of SrHAp were carried out by using X-ray diffraction technique (XRD). The results showed that strontium is incorporated into hydroxyapatite where its substitution for calcium increases in the lattice parameters, and Sr3(PO4)2 can be detected at 900°C. The SEM micrographs showed that SrHAp films exhibited porous structure before develop to a cross-linking structure.


2013 ◽  
Vol 734-737 ◽  
pp. 2328-2331
Author(s):  
Yu Fei You ◽  
C.H. Xu ◽  
Jing Zhe Wang ◽  
Jun Peng Wang

Sol-gel method is used for the formation of Pb0.499Sr0.499TiO3 (PST)thin films. The initial films were prepared with spin coating sol solution on silicon wafer and drying at room temperature and then heating coated dry sol film at 400°C for 10min. This process was repeated for 1-4 times to obtain 4 initial films with different thicknesses. The 4 initial films were annealed at 700°C for 2h to obtain PST ceramics films. The morphologies of the surface and cross-section of PST films were observed with a scanning electronic microscope (SEM). The phase structures of PST films were analyzed using X-ray diffraction meter (XRD). Experimental results show that PST film prepared by coating sol on silicon with different thicknesses can be high smooth,uniform and compact film.


2005 ◽  
Vol 900 ◽  
Author(s):  
A. Deptuła ◽  
Kenneth C Goretta ◽  
Tadeusz Olczak ◽  
Wieslawa Lada ◽  
Andrzej G. Chmielewski ◽  
...  

ABSTRACTTitanium oxide and titanates based on Ba, Sr and Ca were prepared from commercial solutions of TiCl4 and HNO3. The main preparation steps for the sols consisted of elimination of chloride anions by distillation with nitric acid and addition of metal hydroxides for the titanates. Resulting sols were gelled and used to (1) prepare irregularly shaped powders by evaporation; (2) produce by a dipping technique thin films on glass, Ag, or Ti substrates; and (3) produce spherical powders (diameters <100 μm) by solvent extraction. Results of thermal and X-ray-diffraction analyses indicated that the temperatures required to form the various compounds were lower than those necessary to form the compounds by conventional solid-state reactions and comparable to those required with use of organometallic based sol-gel methods. Temperatures of formation could be further reduced by addition of ascorbic acid to the sols.


2012 ◽  
Vol 204-208 ◽  
pp. 4207-4210 ◽  
Author(s):  
Yu Fei You ◽  
C. H. Xu ◽  
Jun Peng Wang ◽  
Yu Liang Liu ◽  
Jin Feng Xiao ◽  
...  

Sol-gel method is used for the formation of Pb(Zr0.63Ti0.37)O3(PZT) thin films. The initial films were formed with spin coating sol solution on silicon wafer and drying coated wet sol film at 300°C for 5min. This process was repeated for 1-4 times to obtain 4 initial films with different thicknesses. 4 initial films were annealed at 500°C for 2h to obtain PZT ceramics films. The morphologies of the surface and cross-section of PZT films were observed with a scanning electronic microscope (SEM). The phase structures of PZT films were analyzed using an X-ray diffraction meter (XRD). Experimental results show that PZT film prepared by coating wet sol on silicon once can be high smooth and compact film.


1997 ◽  
Vol 12 (3) ◽  
pp. 596-599 ◽  
Author(s):  
Ji Zhou ◽  
Qing-Xin Su ◽  
K. M. Moulding ◽  
D. J. Barber

Ba(Mg1/3Ta2/3)O3 thin films were prepared by a sol-gel process involving the reaction of barium isopropoxide, tantalum ethoxide, and magnesium acetate in 2-methoxyethanol and subsequently hydrolysis, spin-coating, and heat treatment. Transmission electron microscopy, x-ray diffraction, and Raman spectroscopy were used for the characterization of the thin films. It was shown that the thin films tend to crystallize with small grains sized below 100 nm. Crystalline phase with cubic (disordered) perovskite structure was formed in the samples annealed at a very low temperature (below 500 °C), and well-crystallized thin films were obtained at 700 °C. Although disordered perovskite is dominant in the thin films annealed below 1000 °C, a low volume fraction of 1 : 2 ordering domains was found in the samples and grows with an increase of annealing temperature.


2009 ◽  
Vol 1199 ◽  
Author(s):  
Danilo G Barrionuevo ◽  
Surinder P Singh ◽  
Maharaj S. Tomar

AbstractWe synthesized BiFe1-xMnxO3 (BFMO) for various compositions by sol gel process and thin films were deposited by spin coating on platinum Pt/Ti/SiO2/Si substrates. X-ray diffraction shows all the diffraction planes corresponding to rhombohedrally distorted perovskite BiFeO3 structure. The absence of any impurity phase in the films suggests the incorporation Mn ion preferentially to Fe site in the structure for low concentration. Magnetic measurements reveal the formation of ferromagnetic phase at room temperature with increased Mn substitution. On the other hand, ferroelectric polarization decreases with increasing Mn ion concentration. Raman studies suggest the dopant induced structural distortion.


2021 ◽  
Vol 2070 (1) ◽  
pp. 012098
Author(s):  
P K Ojha ◽  
S K Mishra

Abstract Vanadium dioxides are strongly correlated systems which undergo an insulator-metal transition (IMT) from a low-temperature semiconducting phase to a high-temperature metallic phase. Among them, Vanadium dioxide (VO2) undergoes IMT close to room temperature, accompanied by a structural transition resulting change of several orders of magnitude in the electrical and optical properties. Here, we present the synthesis of VO2 by sol-gel process which employs cost-effective precursors to synthesize pure phase of VO2 thin films. The synthesized thin films were characterized using an X-ray diffraction (XRD) to confirm phase purity and high resolution scanning electron microscope (HR-SEM) to study the crystallite and particle size for the synthesized films. The film’s surface was analyzed by X-ray photoelectron spectroscopy (XPS) to determine the valence state and chemical composition of vanadium dioxide.


2003 ◽  
Vol 785 ◽  
Author(s):  
R. Guzman ◽  
M.S. Tomar ◽  
R.E. Melgarejo

ABSTRACTThere is a great deal of interest in CaCu3Ti4O12 system for dielectric applications. We have studied Ca1-xSrxCu3Ti4O12 system for different compositions. The material is synthesized by sol-gel chemical solution route and thin films were deposited by spin coating. Thin films were investigated by x-ray diffraction and Raman spectroscopy for structural properties. These results indicate a solid solution for the compositions x = 0.00 to 0.80. The SEM micrographs shows the uniform films at 800° C, but the dielectric response of Ca1-xSrxCu3Ti4O12 (x = 0.00) shows the dielectric constant value below 200.


2000 ◽  
Vol 15 (12) ◽  
pp. 2653-2657 ◽  
Author(s):  
Maosong Tong ◽  
Guorui Dai ◽  
Yuanda Wu ◽  
Xiuli He ◽  
Wei Yan ◽  
...  

Thermogravimetric analysis, x-ray photoelectron spectroscopy, and x-ray diffraction results and the humidity sensing properties of poly(vanadium–molybdenum acid) H2V9.5Mo2.5O32.0 · 8.8H2O xerogel thin films, which were fabricated by the sol-gel process, are described in this paper. The conductance and the capacitance of the thin films strongly depend on the relative humidity. Different electrodes have different influences on the humidity-sensing properties of the thin films.


2006 ◽  
Vol 514-516 ◽  
pp. 128-132 ◽  
Author(s):  
Agata Lisińska-Czekaj ◽  
M. Czaja ◽  
Lucjan Kozielski ◽  
Dionizy Czekaj ◽  
M. Piechowiak ◽  
...  

The present study is devoted to synthesis and investigation of photoluminescence in the nanosized Bi4Ti3O12 (BTO) thin films. The randomly oriented BTO thin films have been obtained by a modified hybrid sol-gel process. Bismuth nitrate and titanium (IV) butoxide were used as the starting materials. The thin films were deposited on silicon, glass and stainless steel by spin coating and crystallized by the conventional thermal annealing at temperature T=650°C. Formation of the layer perovskite-type structure of the orthorhombic symmetry was confirmed by X-ray diffraction method. Conservation of the chemical composition was investigated by energy dispersive spectroscopy. The UV luminescence has been observed in BTO thin films at room temperature. Results on luminescence excitation and emission in bismuth titanate thin films are given in the present paper.


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