Optical and Electrical Properties of Sol-Gel Processed Gd Doped Ferroelectric PLZT Thin Films

2002 ◽  
Vol 718 ◽  
Author(s):  
Reji Thomas ◽  
Shoich Mochizuki ◽  
Toshiyuki Mihara ◽  
Tadashi Ishida
Keyword(s):  
Thin Films ◽  
Perovskite Phase ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Visible Region ◽  
Fused Silica ◽  
Electrical Measurements ◽  
Seeding Layer ◽  
Crystalline Films ◽  
Plzt Thin Films

AbstractGadolinium(Gd) doped ferroelectric lead lanthanum zirconate titanate (PLGZT 6/2/65/35) thin films were prepared by sol-gel spin coating technique. Fused silica and platinized silicon were used as substrates. Two-step pre-annealing heat treatment was employed to prepare crack free films. Annealing temperature was optimized though the x-ray diffraction studies to prepare films in single perovskite phase. Effects of Pb concentration and the seeding layer on the crystallization were studied. Optical transmission spectra were recorded and from this, refractive index, extinction coefficient and thickness were calculated for amorphous films on fused silica annealed at 400°C. In addition, the resultant films showed more than 60% transmission in the visible region. The electrical measurements were conducted on metal-ferroelectric-metal (MFM) capacitors. Ferroelectric properties of crystalline films were studied by plotting the P-E hysteresis loop.

Structural, Dielectric and Pyroelectric properties of Lanthanum modified Lead Titanate Thin Films

2004 ◽  
Vol 811 ◽  
Author(s):  
Sonalee Chopra ◽  
Seema Sharma ◽  
T.C. Goel ◽  
R.G. Mendiratta
Keyword(s):  
Thin Films ◽  
Lead Titanate ◽  
Mechanical Stability ◽  
Perovskite Phase ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Microstructural Analysis ◽  
Pyroelectric Coefficient ◽  
Structural Investigations ◽  
Glass Substrates

ABSTRACTFerroelectric lead lanthanum titanate (Pb1−xLaxTi1−x/4O3) (PLTx) thin films (x=0.04,0.08 and 0.12) have been prepared by sol-gel spin coating process on ITO coated 7059 Corning glass substrates. Investigations have been made on the crystal structure, surface morphology, dielectric and ferroelectric properties of the thin films. For a better understanding of the crystallization mechanism, the structural investigations were carried out at various annealing temperatures (350°C, 450°C, 550°C and 650°C). Characterization of these films by X-ray diffraction shows that the films annealed at 650°C exhibit tetragonal structure with perovskite phase. Replacement of lanthanum in lead titanate results in reduction of tetragonal ratio (c/a), resulting in better mechanical stability. Microstructural analysis of the films are carried out by taking the Atomic Force Microscope (AFM) pictures. AFM images are characterized by slight surface roughness with a uniform crack free, densely packed structure. Dielectric, pyroelectric and ferroelectric studies carried out on these films have been reported. Dielectric constant and pyroelectric coefficient increase while Curie temperature decreases with increase in La content. The pyroelectric figures of merit of the films have also been calculated which suggest that 8% lanthanum is best suited material for pyroelectric detectors owing to its high pyroelectric coefficient (∼ 29nC/cm2 K), high voltage responsivity (∼420Vcm2/J), high detectivity (∼1.04×10−5Pa−1/2) and low variation of pyrocoefficient with temperature.

Preparation and Electrical Properties of Bi0.9Nd0.1Fe0.925Mn0.075O3 Thin Films

2012 ◽  
Vol 557-559 ◽  
pp. 1933-1936
Author(s):  
Ning Yan ◽  
Sheng Hong Yang ◽  
Yue Li Zhang
Keyword(s):  
Thin Films ◽  
Remanent Polarization ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Electrical Measurements ◽  
X Ray ◽  
Low Leakage ◽  
Bifeo3 Thin Films ◽  
Low Leakage Current

Pure BiFeO3(BFO) and Bi0.9Nd0.1Fe0.925Mn0.075O3(BNFM) thin films were deposited on Pt(111)/Ti/SiO2/Si substrate by sol-gel method. X-ray diffraction analysis showed that all the films were single perovskite structure and a phase transition appeared in Nd–Mn codoped BiFeO3 thin films. Electrical measurements indicated that the ferroelectric properties of BFO thin films were significantly improved by Nd and Mn codoping. BNFM films exhibit a low leakage current and a good P-E hysteresis loop. The remanent polarization (Pr) value of 74μC/cm2has been obtained in BNFM films, while the coercive field (Ec) is 184kV/cm.

The role of excess Pb and PbO overpressure on the microstructural development in polycrystalline PZT thin films

1994 ◽  
Vol 52 ◽  
pp. 582-583
Author(s):  
M. J. Lefevre ◽  
D. B. Dimos ◽  
J. S. Speck
Keyword(s):  
Thin Films ◽  
Data Storage ◽  
Perovskite Phase ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Pyrochlore Phase ◽  
Optical Data Storage ◽  
Optical Data ◽  
Microstructural Development

Ferroelectric thin films have recently received considerable attention because of their potential in a range of device applications including both volatile and non-volatile memories, optical data storage, and other electrooptic applications (e.g. waveguides, switches, and modulators). The Pb-based perovskites, such as Pb(Zr,Ti)O3, have many properties that make them attractive for such applications because of their high switchable remanant polarization. In addition, many applications require integration of the ferroelectric with semiconductors. In our work we are studying the crystallization sequence of PZT 40/60 (PbZr0.40Ti0.60O3) grown on platinized silicon substrates, with an overall structure given as PZT/Pt/Ti/SiO2Si. The Ti and Pt are sequentially evaporated onto the oxidized Si substrate. Alkoxide-derived films are spun onto these substrates to form a dry amorphous gel2. The crystallization of the sol-gel film proceeds upon heating to temperatures in the range of 400-700°C. Lead volatility is one of the critical issues in the crystallization of Pb-based perovskite thin films. We have carried out a systematic study on the role of a lead atmosphere in crystallization for PZT (40/60). When heat treated the film forms a transitory pyrochlore phase at intermediate temperatures before transforming to the perovskite phase. This non-ferroelectric pyrochlore phase may stabilize if lead stoichiometry is not maintained, leading to poor optical and ferroelectric properties in the thin films.

Novel thin films of titanium dioxide particles synthesized by a sol-gel process

1995 ◽  
Vol 10 (12) ◽  
pp. 3068-3078 ◽  
Author(s):  
V.J. Nagpal ◽  
R.M. Davis ◽  
S.B. Desu
Keyword(s):  
Thin Films ◽  
Titanium Dioxide ◽  
Sol Gel ◽  
Particle Surface ◽  
Composite Films ◽  
Visible Region ◽  
Silicon Substrates ◽  
Transparent Films ◽  
Sol Gel Process ◽  
Crystalline Films

Novel thin films of ultrafine titanium dioxide particles dispersed in a matrix of hydroxypropylcellulose (HPC) polymer have been made on quartz and silicon substrates. The titanium dioxide particles were made by the hydrolysis and condensation of titanium tetraethoxide (TEOT) in solutions of HPC in a mixture of ethanol and water. HPC controlled the particle size by adsorbing at the particle surface during the growth process and generating repulsive steric forces. The TiO2/HPC composite films were transparent in the visible region and completely blocked ultraviolet radiation at 300 nm. These films were crack-free and uniform in composition and thickness. Transparent films of amorphous TiO2 were made by burning out the HPC at 500 °C. These films were highly uniform and had no macroscopic cracks. X-ray diffraction revealed a transition to the anatase form upon sintering at 600 °C. A film sintered at 700 °C had a porosity of 38%. The crystalline films remained transparent until they densified at 800 °C.

Structure and Dielectric Properties of Mn, Co, and Ni-Doped LaSrFeO3 Films

2013 ◽  
Vol 575-576 ◽  
pp. 499-503
Author(s):  
Bin Fu ◽  
Yang Lu Hou ◽  
Wei Bing Wu ◽  
Xing Hua Fu
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Dielectric Properties ◽  
Smooth Surface ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Electrical Measurements ◽  
Doping Amount ◽  
Pure Perovskite Phase ◽  
Gel Technique

Mn, Co, and Ni-doped La0.5Sr0.5FeO3thin films were prepared by the sol-gel technique. The structure and dielectric properties of the films were studied by XRD, SEM, and electrical measurements. The morphology observation demonstrated these films had uniform grain size and smooth surface. The dielectric properties of La0.5Sr0.5FeO3films were improved by the replacement of Fe with Mn, Co, and Ni. The doping amount of Mn, Co, and Ni for the optimal dielectric properties of La0.5Sr0.5FeO3films is 5%, 2%, and 3%, respectively. The observed pure perovskite phase of the doped films suggested the dissolution of Mn, Co, and Ni in La0.5Sr0.5FeO3crystal lattice.

Effect of measurement temperature on the dielectric and ferroelectric properties of various sol-gel derived PLZT thin films

1997 ◽  
Vol 17 (1-4) ◽  
pp. 213-220
Author(s):  
Finnbarr McCarthy ◽  
Kevin McCarthy ◽  
Gimtong Teowee ◽  
Tracie Bukowski ◽  
Tom Alexander ◽  
...  
Keyword(s):  
Thin Films ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Measurement Temperature ◽  
Plzt Thin Films

scholarly journals Robust ferroelectricity enhancement of PZT thin films by a homogeneous seed layer

2021 ◽  
Author(s):  
jie jiang ◽  
Lei Liu ◽  
Kuo Ouyang ◽  
Zhouyu Chen ◽  
Shengtao Mo ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Remanent Polarization ◽  
Perovskite Phase ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Pzt Thin Films ◽  
Large Dielectric Constant ◽  
Sol Gel Process ◽  
A New Technique

Abstract With its excellent ferroelectric properties such as large dielectric constant and large remanent polarization, PZT thin films are extensively used in micro-sensors and other devices. In this study, the sol-gel process was used to fabricate Pb(Zr0.52Ti0.48)O3 thin films with Pb(ZrxTi1−x)O3 seed islands. The experimental consequences demonstrate that all the Pb(Zr0.52Ti0.48)O3 thin films with Pb(ZrxTi1−x)O3 seeds show pure perovskite phase with no other impurity phases, and the electrical properties of Pb(Zr0.52Ti0.48)O3 thin films modified by Pb(ZrxTi1−x)O3 seed islands with different Zr/Ti ratios are improved, such as remanent polarization increased, dielectric properties increased, coercive electric field decreased, leakage current density decreased, etc. In particular, the electrical properties of the Pb(Zr0.52Ti0.48)O3 thin films with Pb(ZrxTi1−x)O3 seed islands are the most optimal when the x is 0.52. This paper provides a new technique for optimizing the electrical properties of PZT thin films, which is of great significance for breaking through the bottleneck of the development of ferroelectric memory.

Ferroelectric Thin Films Via Sol-Gel Processing of Singlesource Precursors

1993 ◽  
Vol 310 ◽  
Author(s):  
C.D. Chandler ◽  
M.J. Hampden-Smith ◽  
R.W. Schwartz
Keyword(s):  
Thin Films ◽  
Perovskite Phase ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Dip Coating ◽  
Mixed Metal Oxide ◽  
Mixed Metal ◽  
Oxide Powders ◽  
Metal Organic ◽  
Gel Processing

AbstractThe use of single-source mixed metal-organic precursors specifically designed for the formation of crystalline perovskite phase mixed metal oxide powders has been investigated. Pyridine solutions of divalent metal α-hydroxycarboxylates of general empirical formula A(O2CCMe2OH)2 where A = Pb, Ca, Sr, Ba; Me = methyl, were designed to react with metal alkoxides, for example, Ti(O-i-Pr)4, with the elimination of two equivalents of alcohol to form species with fixed A:B stoichiometry of 1:1 according to the equation: A(O2CCMe2OH)2 + B(OR)4 → A(O2CCMe2O)2B(OR)2 + 2HOR. Hydrolysis of these compounds in pyridine produces clear solutions which on removal of the solvent in vacuo, yield yellow powders. These powders readily dissolve in ethanol to give solutions from which thin films can be formed either by dip-coating or spin coating. The crystallization behavior, composition and ferroelectric properties of these films is discussed. The crystallization of the films generally required substantially higher temperatures compared to powders obtained from the same precursor solutions.

Preparation of Perovskite Conductive LaNiO3 Films by Sol-Gel Techniques

2006 ◽  
Vol 933 ◽  
Author(s):  
Pei-Ying Lai ◽  
Jen-Sue Chen
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Raw Materials ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Metallic Thin Films ◽  
X Ray Diffraction ◽  
Electrical Measurements ◽  
Metallic Oxide ◽  
X Ray

ABSTRACTMetallic thin films of LaNiO3 (LNO) have been prepared by the sol-gel method using lanthanum nitrate [La(NO3)3·6H2O] and nickel acetate [Ni(CH3COO)2·4H2O] as raw materials. X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and electrical measurements were used to characterize the multilayer LNO thin films. The perovskite phase appears after annealing at temperatures above 600 °C. LNO thin films are n-type metallic oxide. The lowest resistivity is 621 °Ω-cm after annealing at 600 °C, and the carrier concentration is 6.09×1022/cm3.

Studies on the Preparation and Characterization of Ferroelectric PLZT Film Capacitors

2011 ◽  
Vol 110-116 ◽  
pp. 5483-5486
Author(s):  
Li Liu ◽  
Hua Wang ◽  
Ji Wen Xu ◽  
Ming Fang Ren ◽  
Ling Yang
Keyword(s):  
Thin Films ◽  
Remanent Polarization ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Pyrochlore Phase ◽  
X Ray Diffraction ◽  
Glass Substrates ◽  
Plzt Thin Films ◽  
Coercive Electric Field

(Pb0.92La0.08)(Zr0.65Ti0.35) O3(PLZT) thin films were fabricated on indium-doped tin oxide (ITO)-coated glass substrates to create transparent capacitor by the sol-gel method following annealing process. X-ray diffraction analysis shows that the PLZT thin films are polycrystalline with a single perovskite phase at 650°C. The ferroelectric, electrical and optical properties of these films were investigated in detail as a function of annealing temperature. Measurements with the PLZT films annealed at 650°C yielded the following: relative permittivity≈775 and dielectric loss (tanδ) ≈0.054, leakage current of 7.1× 10-9A, and remanent polarization of 38 μC/cm2 and the coercive electric field of 55 kV/cm and transparency of 88%. The pure perovskite films exhibit better properties than those films which have some fraction of pyrochlore phase.

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