STRUCTURAL AND ELECTRICAL PROPERTIES OF Nb5+ SUBSTITUTED PZT CERAMICS

2005 ◽  
Vol 19 (30) ◽  
pp. 1783-1791 ◽  
Author(s):  
O. P. THAKUR ◽  
CHANDRA PRAKASH
Keyword(s):  
Grain Size ◽  
Transition Temperature ◽  
Electrical Properties ◽  
Raw Materials ◽  
Pzt Ceramics ◽  
X Ray ◽  
Niobium Doping ◽  
Average Grain Size ◽  
Structural And Electrical Properties ◽  
Sample Structure

The effect of niobium doping on the structure and electrical properties with the following compositions Pb ( Zr 0.52 Ti 0.48)1-5X/4 Nb X O 3 with 0<x<0.025 was investigated. The materials were prepared by the usual ceramic technique using high purity raw materials. Disc-shaped samples of each compositions were sintered at 1250°C for 3 hours. The sample structure was determined by X-ray diffractometry. The average grain size, the maximum dielectric permittivity and the remnant polarization first increases up to x = 0.005 concentration of Nb 5+ and then decreases with higher concentration of niobium, while the coercive field does not show any variation. The transition temperature decreases with the increase in niobium concentration.

Fabrication and study the effect of the laser on the properties of the compound Tl2-xHgxBa2-ySryCa2Cu3O10+δ superconductor

2018 ◽  
pp. 168
Author(s):  
A. Kareem Dahash Ali ◽  
Nihad Ali Shafeek
Keyword(s):  
Transition Temperature ◽  
Solid State ◽  
Hydrostatic Pressure ◽  
Electrical Properties ◽  
Co2 Laser ◽  
Temperature Shift ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural And Electrical Properties

This study included the fabrication of    compound (Tl2-xHgxBa2-ySryCa2Cu3O10+δ) in a manner solid state and under hydrostatic pressure ( 8 ton/cm2) and temperature annealing(850°C), and determine the effect of the laser on the structural and electrical properties elements in the compound, and various concentrations of x where (x= 0.1,0.2,0.3 ). Observed by testing the XRD The best ratio of compensation for x is 0.2 as the value of a = b = 5.3899 (A °), c = 36.21 (A °) show that the installation of four-wheel-based type and that the best temperature shift is TC= 142 K  .When you shine a CO2 laser on the models in order to recognize the effect of the laser on these models showed the study of X-ray diffraction of these samples when preparing models with different concentrations of the values ​​of x, the best ratio of compensation is 0.2 which showed an increase in the values ​​of the dimensions of the unit cell a=b = 5.3929 (A °), c = 36.238 (A°). And the best transition temperature after shedding laser is TC=144 K. 

Structural and Ferroelectric Properties of SrBi2Ta2O9 Thin Films

1994 ◽  
Vol 361 ◽  
Author(s):  
Kazushi Amanuma ◽  
Takashi Hase ◽  
Yoicht Mtyasaka
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Structural Change ◽  
Electrical Properties ◽  
Ferroelectric Properties ◽  
Si Substrates ◽  
Average Grain Size ◽  
Structural And Electrical Properties ◽  
Sims Analysis ◽  
Film Preparation

ABSTRACTStructural and electrical properties were investigated for chemically prepared SrBi2Ta2O9(SBT) thin films on Pt/Ti/SiO2/Si substrates. Good ferroelectric properties were obtained with a Pt top electrode: Pr=10.0μC/cm2 and Ec-34kV/cm. Au top electrodes resulted in smaller Pr. However, no fatigue was observed up to 109 switching cycles regardless of the top electrode material. Grains were spherical, not columnar, and the average grain size was 200nm. A marked structural change took place in the bottom Pt/Ti electrode during film preparation. The SIMS analysis indicates the reaction between Bi and Pt

Investigation on the Correlation between Structural and Electrical Properties of Lanthanum Doped Barium Titanate Ceramics

2016 ◽  
Vol 860 ◽  
pp. 99-104
Author(s):  
Masum Billah ◽  
Md Miftaur Rahman
Keyword(s):  
Grain Size ◽  
Electrical Properties ◽  
Barium Titanate ◽  
Curie Temperature ◽  
Raw Materials ◽  
Structure Property ◽  
Structural And Electrical Properties ◽  
Doped Barium Titanate ◽  
Titanate Ceramics ◽  
Relationship Of

The structure-property relationship of 0.3, 0.5 and 0.7mole% lanthanum (La2O3) doped Barium titanate (BaTiO3) ceramics prepared by solid state sintering under different sintering conditions were investigated in this research. The raw materials were La2O3 (grain size=~80nm) and BaTiO3 (grain size=100nm) powders. Field Emission Scanning Electron Microscope (FE-SEM) was used to examine grain size and surface morphology of sintered pellets & X-Ray Diffraction analysis was conducted to identify crystal structure. The results showed significantly improved grain size and electrical properties of BaTiO3 for 0.5 mole% La2O3 with desired grain size (0.8-1.3μm), high densification (>90% theoretical density) and stable dielectric constant (12700) at room temperature (f=100Hz) by lowering curie temperature around 30oC by sintering at 1300oC for 8 hrs. A gradual deterioration follows with increased doping concentration. So the research revealed that proper La3+ concentration can inhibit grain size and lower Curie temperature hence significantly improving the electrical properties of BaTiO3 ceramics.

scholarly journals Structural And Electrical Properties Of The Selected Rare-Earth Oxychlorides

2015 ◽  
Vol 60 (3) ◽  
pp. 1595-1602 ◽  
Author(s):  
M. Dziubaniuk ◽  
J. Wyrwa ◽  
M. Bućko ◽  
M. Rękas
Keyword(s):  
Rare Earth ◽  
Electrical Properties ◽  
Single Phase ◽  
Electrochemical Impedance ◽  
Diffraction Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Average Grain Size ◽  
Structural And Electrical Properties ◽  
Sintering Conditions

Abstract The preparation and sintering conditions of the selected rare-earth oxychlorides REOCl (Re=La, Nd, Sm, Gd) were determined. The purity of materials phase compositions was confirmed by X-ray diffraction method. Further analysis of the data enabled lattice parameters and average grain size determination. The electrical properties of the single phase REOCl materials were investigated by Electrochemical Impedance Spectroscopy in wide temperature range in atmospheric air. The spectra were analyzed by the equivalent circuit fitting. Basing on the values of equivalent circuits parameters the specific conductivities were calculated and presented in the Arrhenius coordinates. Energies of activation were calculated. The determined structural and electrical properties of four different rare-earth oxychlorides were directly compared.

ELECTRICAL PROPERTIES OF Nb-DOPED Pb(Zr0.52Ti0.48)O3 CERAMICS

2009 ◽  
Vol 23 (01) ◽  
pp. 105-111 ◽  
Author(s):  
PIYACHON KETSUWAN ◽  
YONGYUT LAOSIRITAWORN ◽  
SUPON ANANTA ◽  
RATTIKORN YIMNIRUN
Keyword(s):  
Dielectric Constant ◽  
Grain Size ◽  
Electrical Properties ◽  
Mixed Oxide ◽  
Room Temperature ◽  
Doping Concentration ◽  
Pzt Ceramics ◽  
Average Grain Size ◽  
Nb Doping ◽  
Room Temperature Dielectric Constant

The Pb ( Zr 0.52 Ti 0.48) O 3 ceramics with 0.75, 1.0, 1.25 and 1.50%wt of Nb 2 O 5 addition were prepared by a conventional mixed oxide technique. It was found that the average grain size of the ceramics decreased from 6 to 1 μm with increasing doping concentration to 1.5%wt. The room temperature dielectric constant and d33 reached maximum values of 1050 and 285 pC/N, respectively, at 1%wt Nb -doping. The electrical coercivity (Ec) of Nb -doped PZT decreased, while the polarization values increased, with increasing doping concentration. Most importantly, this study shows that Nb 2 O 5-doped PZT ceramics exhibits soft piezoelectric and enhanced ferroelectric behaviors, and the optimum properties can be obtained using suitable doping concentration.

scholarly journals Structural and Electrical Studies on ZnO-Based Thin Films by Laser Irradiation

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Shanyue Zhao ◽  
Yinqun Hua ◽  
Ruifang Chen ◽  
Jian Zhang ◽  
Ping Ji
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Electrical Properties ◽  
Grain Boundaries ◽  
Laser Irradiation ◽  
Nonlinear Coefficient ◽  
Acceptor State ◽  
Xrd Pattern ◽  
Electrical Studies ◽  
Structural And Electrical Properties

The effects of laser irradiation on the structural and electrical properties of ZnO-based thin films were investigated. The XRD pattern shows that the thin films were highly textured along thec-axis and perpendicular to the surface of the substrate. Raman spectra reveal that Bi2O3segregates mainly at ZnO-ZnO grain boundaries. After laser irradiation processing, the grain size of the film was reduced significantly, and the intrinsic atomic defects of grain boundaries and Bi element segregated at the grain boundary were interacted frequently and formed the composite defects of acceptor state. The nonlinear coefficient increased to 24.31 and the breakdown voltage reduced to 5.34 V.

INVESTIGATIONS ON Sm- AND Nb-SUBSTITUTED PZT CERAMICS

2006 ◽  
Vol 20 (29) ◽  
pp. 1879-1882 ◽  
Author(s):  
CHANDRA PRAKASH ◽  
J. K. JUNEJA
Keyword(s):  
Dielectric Constant ◽  
Single Phase ◽  
Xrd Analysis ◽  
Chemical Formula ◽  
X Ray Diffraction ◽  
Pzt Ceramics ◽  
Ceramic Method ◽  
X Ray ◽  
Niobium Doping ◽  
Constant Versus

In the present paper, we report the effect of Samarium substitution and Niobium doping on the properties of a PZT(52:48). The properties studied are: structural, dielectric and ferroelectric. The samples with chemical formula Pb 0.99 Sm 0.01 Zr 0.52 Ti 0.48 O 3 were prepared by solid-state dry ceramic method. Small amount (0.5 wt%) of Nb 2 O 5 was also added. X-ray diffraction (XRD) analysis showed formation of a single phase with tetragonal structure. Dielectric properties were studied as a function of temperature and frequency. Transition temperature, Tc, was determined from dielectric constant versus temperature plot. The material shows well-defined ferroelectric (PE) hysteresis loop.

Effect of Composition on the Morphology and Hardness of Nanostructured Cu Based Composite and Alloy Powders/Granules Produced by High Energy Mechanical Milling

2007 ◽  
Vol 29-30 ◽  
pp. 143-146 ◽  
Author(s):  
Aamir Mukhtar ◽  
De Liang Zhang ◽  
C. Kong ◽  
P. R. Munroe
Keyword(s):  
Grain Size ◽  
Mechanical Milling ◽  
Alloy Powder ◽  
High Energy ◽  
Al2o3 Nanoparticles ◽  
X Ray ◽  
Fine Powders ◽  
Average Grain Size ◽  
Powder Particles

Cu-(2.5 or 5.0vol.%)Al2O3 nanocomposite balls and granules and Cu-(2.5vol.% or 5.0vol.%)Pb alloy powder were prepared by high energy mechanical milling (HEMM) of mixtures of Cu and either Al2O3 or Pb powders. It was observed that with the increase of the content of Al2O3 nanoparticles from 2.5vol.% to 5vol.% in the powder mixture, the product of HEMM changed from hollow balls into granules and the average grain size and microhardness changed from approximately 130nm and 185HV to 100nm and 224HV, respectively. On the other hand, HEMM of Cu–(2.5 or 5.0vol.%) Pb powder mixtures under the same milling conditions failed to consolidate the powder in-situ. Instead, it led to formation of nanostructured fine powders with an average grain size of less than 50nm. Energy dispersive X-ray mapping showed homogenous distribution of Pb in the powder particles in Cu–5vol.%Pb alloy powder produced after 12 hours of milling. With the increase of the Pb content from 2.5 to 5.0 vol.%, the average microhardness of the Cu-Pb alloy powder particles increases from 270 to 285 HV. The mechanisms of the effects are briefly discussed.

Thermal Diffusivity and Conductivity of La0.7Ca0.3-xSrxMnO3 (x=0 to 0.10)

2012 ◽  
Vol 501 ◽  
pp. 319-323
Author(s):  
Hasan A. Alwi ◽  
Lay S. Ewe ◽  
Zahari Ibrahim ◽  
Noor B. Ibrahim ◽  
Roslan Abd-Shukor
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Grain Size ◽  
Transition Temperature ◽  
Thermal Diffusivity ◽  
Electrical Properties ◽  
Room Temperature ◽  
Electronic Contribution ◽  
Insulator Metal Transition ◽  
Thermal And Electrical Properties

We report the room temperature thermal conductivity κ and thermal diffusivity α of polycrystalline La0.7Ca0.3-xSrxMnO3 for x = 0 to 0.1. The samples were prepared by heating at 1220 and 1320oC. The insulator-metal transition temperature, TIM and thermal diffusivity increased with Sr content. Phonon was the dominant contributor to thermal conductivity and the electronic contribution was less than 1%. Enhancement of electrical conductivity σ and thermal diffusivity for x ≥ 0.08 was observed in both series of samples. The grain size of the samples (28 to 46 µm) does not show any affect on the thermal and electrical properties.

Properties and Application of Undoped Hydrogenated Microcrystalline Silicon Thin Films

1989 ◽  
Vol 149 ◽  
Author(s):  
J. Kanicki ◽  
E. Hasan ◽  
D. F. Kotecki ◽  
T. Takamori ◽  
J. H. Griffith
Keyword(s):  
Grain Size ◽  
Deposition Temperature ◽  
Etch Rate ◽  
Chemical Vapor ◽  
Microcrystalline Silicon ◽  
Silicon Thin Films ◽  
Hydrogen Dilution ◽  
Average Grain Size ◽  
Structural And Electrical Properties ◽  
Deposition Conditions

ABSTRACTDevice quality undoped hydrogenated microcrystalline silicon has been prepared by plasma enhanced chemical vapor deposition under different conditions. The dependence of physical, chemical, structural, and electrical properties on the deposition conditions has been investigated. Conductive (conductivity above 10−3Ω−1 cm−1) and resistive (conductivity around 10−9Ω−1cm−1) layers having approximately the same grain size, at a given substrate temperature, have been deposited between 200 and 500°C at two different hydrogen dilutions. Independently of the hydrogen dilution, the average grain sized is dependent on the deposition temperature and the film thickness; and a maximum average grain size of about 40 nm has been achieved for a thick film deposited at 500°C. The density of paramagnetic defects also increases with increasing deposition temperature, which indicates that more dangling bond defects are introduced as the total area of the grain boundaries increases. The etch rate decreases with increasing deposition temperature, and for the films deposited at 250 and 500°C the etch rate has been measured to be 6.6 and 2.7 nm/min, respectively. Thin film transistors incorporating a microcrystalline channel have been fabricated and evaluated. The best device had the following properties: field effect mobility, threshold voltage, and on/off current ratio of about 0.8 cm2/V sec, below 5 V, and around 106, respectively.

Sign in / Sign up

Export Citation Format

Share Document