Micro-Raman Study of Pb(Zr,Ti)O3 Thin Films in Feram

1998 ◽  
Vol 541 ◽  
Author(s):  
Takahiro Kimura ◽  
Yoshimasa Horii ◽  
Tomoji Nakamura ◽  
Koichiro Honda
Keyword(s):  
Thin Films ◽  
Raman Spectra ◽  
Spontaneous Polarization ◽  
Volume Fraction ◽  
Exciting Light ◽  
Pzt Films ◽  
Grain Orientations ◽  
Raman Study ◽  
The Difference

AbstractWe examined the Raman spectra of the tetragonal Pb(Zr, Ti)O3 (PZT) films between FeRAM cells with a micro-Raman apparatus. We found that a Raman light peaked at 600cm−1 polarized linearly perpendicular to the polarization of the exciting light had a different intensity for each of the film.We showed that the difference in the intensities can be explained by the differing distributions of grain orientations in the films. Based on this knowledge, we estimated the volume fraction of 90° domains as well as the average spontaneous polarization of the grains.

Influence of Platinum Bottom Electrodes on the Piezoelectric Performance of PZT Thin Films Hot Sputtered in a High Volume Production Tool

2012 ◽  
Vol 1397 ◽  
Author(s):  
Dirk Kaden ◽  
Hans-Joachim Quenzer ◽  
Martin Kratzer ◽  
Lorenzo Castaldi ◽  
Bernhard Wagner ◽  
...  
Keyword(s):  
Thin Films ◽  
Volume Fraction ◽  
Perovskite Phase ◽  
Annealing Treatment ◽  
High Volume ◽  
Deposition Process ◽  
Pzt Thin Films ◽  
Pzt Films ◽  
High Volume Production ◽  
Volume Production

ABSTRACTIn this work high quality ferroelectric PZT films have been prepared in-situ by hot RF magnetron sputtering. 200 mm wafer were coated with PZT films of 1 μm and 2 μm thickness at sputter rates of 45 nm/min in a high volume production sputtering tool. The films were grown on oxidized Si substrates prepared either with sputtered Ti/TiO2/Pt, sputtered Ti/TiO2/Pt/TiO2 or evaporated Ti/Pt bottom electrodes at substrate holder temperatures in the range from 550 °C to 700 °C. At these temperatures, the material nucleates in the requisite piezoelectric perovskite phase without need of an additional post annealing treatment.The films were investigated with respect to their chemical composition and their crystallographic, piezoelectric and dielectric properties. At an intermediate chuck temperature of 600 °C the PZT thin films were characterized by a minimum volume fraction of secondary nonpiezoelectric phases. A Zr/(Zr+Ti) ratio of 0.53 has been achieved matching the morphotropic phase boundary. By improving the deposition process and poling procedure, a notable high e31,f coefficient of -17.3 C/m2 has been obtained. The corresponding longitudinal piezoelectric constant was determined to have an effective longitudinal piezoelectric coefficient d33,f of 160 pm/V.

Micro-Raman Study of Sol-Gel Grown Pmn-PT Thin Films

1995 ◽  
Vol 392 ◽  
Author(s):  
E. Ching-Prado ◽  
R. W. Tao ◽  
A. R. Guo ◽  
R. S. Katiyar ◽  
A. S. Bhalla
Keyword(s):  
Thin Films ◽  
Raman Spectra ◽  
Sol Gel ◽  
Relaxation Times ◽  
Weighted Average ◽  
Momentum Conservation ◽  
Temperature Dependent ◽  
Raman Study ◽  
Xrd Techniques ◽  
Pt Films

AbstractThin films of 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-PT) were prepared by sol-gel technique and deposited on platinum coated-silicon wafer. The thicknesses of the two films were ∼400 nm and ∼550 nm, respectively. Micro-Raman spectra of the PMN-PT films show strong broad bands centered at 50, 136, 276, 450, 510, 556, and 790 cm−1, which are characteristic of PMN formation. Temperature dependent Raman scattering from 290K to 70K did not show any significant change in the bandwidth of the peaks, meaning thereby that the relaxation times of these phonons are practically temperature independent. The bands are interpreted as due to a break down in the phonon momentum conservation within the Brillouin zone, which is associated with some degree of disorder in the material. As a result, the Raman spectrum is a weighted average of the density of phonon states. Micro-Raman measurements in many different places on the films clearly indicate that they are homogeneous. In addition, the differences found in the Raman spectra of the films, particularly the band at 790 cm−1 is discussed. FT-1R measurements of the PMN-PT films present two broad bands around 260 and 550 cm−1, which are characteristic of perovskite structure and are primarily due to motions of oxygen ions. Also, these bands are compared with those found in PMN single crystal, and with those found in other similar systems, such as PLZT and PSN. SEM and XRD techniques have been used for the structural characterization.

A Thickness Dependent Study of SrBi2Nb2O9 Thin Films

1997 ◽  
Vol 493 ◽  
Author(s):  
W. Pérez ◽  
E. Ching-Prado ◽  
A. Reynés-Figueroa ◽  
R. S. Katiyar ◽  
D. Ravichandran ◽  
...  
Keyword(s):  
Thin Films ◽  
Raman Spectra ◽  
Raman Band ◽  
Sol Gel ◽  
Orthorhombic Symmetry ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
Coexistence Of Phases ◽  
Raman Study ◽  
Si Films

ABSTRACTThin films of SrBi2Nb2O9 (SBN) with thickness of 0.1, 0.2, 0.3 and 0.4 μm were grown by sol-gel technique on platinum/silicon substrates, and annealed at 800°C. Raman spectra of the samples present bands around 170,210, 272, 300,430, 580, 717, and 839 cm−1 which correspond to the SBN formation. The prominent Raman band around 839 cm−1, which is the Alg mode of the orthorhombic symmetry, is assigned to the symmetric stretching of the NbO6 octahedrals. The frequency of this band is found to shift at different places in the same sample, as well as from sample to sample. The frequency and width variations of the Raman bands are discussed in term of ions in non-equilibrium positions, which seem to be related with the crystallization degree in the SBN samples. Also, the Raman study indicates the presence of foreign sharp peaks, which are associated with the coexistence of phases other than SBN. The thickness dependence of the Raman spectra and the X-ray diffraction are also discussed. Finally, the experimental results of the SBN/Pt/Si films grown at 800°C are compared with those obtained at 650°C.

Raman Study of SrBi2Ta2O9 Bi3TiNbO9 Thin Films

1998 ◽  
Vol 541 ◽  
Author(s):  
W. Pérez ◽  
E Ching-Prado ◽  
P.S. Dobal ◽  
A. Reynés-Figueroa ◽  
R.S. Katiyar ◽  
...  
Keyword(s):  
Thin Films ◽  
Raman Spectra ◽  
Layered Structure ◽  
Deposition Method ◽  
Organic Solution ◽  
Solution Deposition ◽  
Si Substrates ◽  
Metal Organic ◽  
Raman Study

AbstractThin films of ferroelectric (SrBi2Ta2O9)x(Bi3TiNbO9)1−x layered structure were prepared for x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0, by metal organic solution deposition method on Pt/TiO2/SiO2/Si substrates. The micro-Raman studies reveal that the samples are mostly homogeneous. The Raman sprectrum for the film with x = 0 shows bands around 60, 170, 232, 256, 337, 569, and 839 cm−1, which indicate Bi3TiNbO9 (BTN) formation. The prominent band around 839 cm−1, which is an A1g mode of the orthorombic symmetry, corresponds to symmetric stretching of the BO6 octahedra. The frequency of this band is found to shift significantly as SrBi2Ta2O9(SBT) material is added to the BTN compound. In this paper, the evolution of the Raman bands with the inclusion of SBT material are presented and discussed. Finally, The Raman spectra of SBT- BTN films are compared with those obtained in SBT-BTN bulk ceramics.

Piezoelectric effect in epitaxial PbZr1−xTixO3 thin films near morphotropic phase boundary region

2005 ◽  
Vol 20 (4) ◽  
pp. 787-790 ◽  
Author(s):  
Yong Kwan Kim ◽  
Sang Sub Kim ◽  
Bongki Lee ◽  
Hyunjung Shin ◽  
Sunggi Baik
Keyword(s):  
Thin Films ◽  
Phase Boundary ◽  
Morphotropic Phase Boundary ◽  
Volume Fraction ◽  
Scanning Force Microscopy ◽  
Boundary Region ◽  
Structural Instability ◽  
Piezoelectric Response ◽  
Storage Devices ◽  
Pzt Films

The relationship between crystal structure and piezo-response was investigated in epitaxially grown PbZr1−xTixO3 (PZT) thin films on Pt(001)/MgO(001) with a thin PbTiO3 interlayer. Insertion of the interlayer resulted in significant relaxation ofthe strain that could be developed in the course of deposition of the PZT films, consequently leading us to single out only the effect of composition. Composition of the morphotropic phase boundary (MPB), at which tetragonal and rhombohedral phases are mixed with the same volume fraction, was found to be ∼0.55 in Ti/(Zr + Ti) ratio in our films, which is close to the value for bulk polycrystalline PZT (∼0.50). The piezoelectric response peaks were two times higher in the MPB regime than in the single phase regime due to structural instability caused by the coexistence of two phases. The results indicate that epitaxial PZT films having the MPB composition are advantageous over those of other compositions for nano-storage devices based on scanning force microscopy.

Effects of the Purity of Metalorganic Sources on the Electrical Properties of Pb(ZrTi)O3 Thin Films by MOCVD

1998 ◽  
Vol 541 ◽  
Author(s):  
M. Shimizu ◽  
M. Yoshida ◽  
H. Fujisawa ◽  
H. Niu
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Electric Fields ◽  
Impurity Effects ◽  
Pzt Thin Films ◽  
Pzt Films ◽  
Current Densities ◽  
Fatigue Characteristics ◽  
The Difference ◽  
Ionic Movement

AbstractEffects of the purity of metalorganic Pb,Zr and Ti precursors (Pb(C2H5)4, Zr(O-tC4H9)4 and Ti(O-iC3 H 7)4) on the electrical properties of Pb(ZrTi)O3 (PZT) thin films prepared by MOCVD were investigated. Generally, PZT thin films prepared using the high purity Pb source precursor had a tendency to show better current densities, breakdown electric fields and switching fatigue characteristics than those of PZT films prepared using the low purity precursor. On the other hand, distinct purity effects of Zr and Ti source precursors were not observed. These experimental results suggest that some types of impurities play important roles as donors and acceptors and influence ionic movement and space charge. At this stage, it is not well understood which impurities contained in precursors play important roles and what is the difference in the impurity effects between Pb, and Zr and Ti precursors.

Effects of dopant concentration on the microstructure of tin- doped indium oxide thin films

1990 ◽  
Vol 48 (4) ◽  
pp. 716-717
Author(s):  
I. A. Rauf
Keyword(s):  
Thin Films ◽  
Indium Oxide ◽  
Ionic Radius ◽  
Free Carrier ◽  
Electron Gun ◽  
Periodic Lattice ◽  
Oxide Thin Films ◽  
Transmission Electron ◽  
The Difference ◽  
Dopant Atoms

To understand the electronic conduction mechanism in Sn-doped indium oxide thin films, it is important to study the effect of dopant atoms on the neighbouring indium oxide lattice. Ideally Sn is a substitutional dopant at random indium sites. The difference in valence (Sn4+ replaces In3+) requires that an extra electron is donated to the lattice and thus contributes to the free carrier density. But since Sn is an adjacent member of the same row in the periodic table, the difference in the ionic radius (In3+: 0.218 nm; Sn4+: 0.205 nm) will introduce a strain in the indium oxide lattice. Free carrier electron waves will no longer see a perfect periodic lattice and will be scattered, resulting in the reduction of free carrier mobility, which will lower the electrical conductivity (an undesirable effect in most applications).One of the main objectives of the present investigation is to understand the effects of the strain (produced by difference in the ionic radius) on the microstructure of the indium oxide lattice when the doping level is increased to give high carrier densities. Sn-doped indium oxide thin films were prepared with four different concentrations: 9, 10, 11 and 12 mol. % of SnO2 in the starting material. All the samples were prepared at an oxygen partial pressure of 0.067 Pa and a substrate temperature of 250°C using an Edwards 306 coating unit with an electron gun attachment for heating the crucible. These deposition conditions have been found to give optimum electrical properties in Sn-doped indium oxide films. A JEOL 2000EX transmission electron microscope was used to investigate the specimen microstructure.

Ion Beam Sputter Deposition Of Ferroelectric Oxide Thin Films

1991 ◽  
Vol 223 ◽  
Author(s):  
Thomas M. Graettinger ◽  
O. Auciello ◽  
M. S. Ameen ◽  
H. N. Al-Shareef ◽  
K. Gifford ◽  
...  
Keyword(s):  
Thin Films ◽  
Lead Zirconate Titanate ◽  
Growth Parameters ◽  
Ion Beam ◽  
Lead Zirconate ◽  
Electro Optic ◽  
Integrated Optical ◽  
Pzt Films ◽  
Ion Beam Sputter Deposition ◽  
Ferroelectric Oxide

ABSTRACTFerroelectric oxide films have been studied for their potential application as integrated optical materials and nonvolatile memories. Electro-optic properties of potassium niobate (KNbO3) thin films have been measured and the results correlated to the microstructures observed. The growth parameters necessary to obtain single phase perovskite lead zirconate titanate (PZT) thin films are discussed. Hysteresis and fatigue measurements of the PZT films were performed to determine their characteristics for potential memory devices.

Study of pumping effect in flow-through electrolysers

1983 ◽  
Vol 48 (8) ◽  
pp. 2232-2248 ◽  
Author(s):  
Ivo Roušar ◽  
Michal Provazník ◽  
Pavel Stuhl
Keyword(s):  
Natural Convection ◽  
Balance Equation ◽  
Volume Fraction ◽  
Industrial Applications ◽  
Pumping Effect ◽  
Flow Through ◽  
The Mean ◽  
The Difference

In electrolysers with recirculation, where a gas is evolved, the pumping of electrolyte from a lower to a higher level can be effected by natural convection due to the difference between the densities of the inlet electrolyte and the gaseous emulsion at the outlet. An accurate balance equation for calculation of the rate of flow of the pumped liquid is derived. An equation for the calculation of the mean volume fraction of bubbles in the space between the electrodes is proposed and verified experimentally on a pilot electrolyser. Two examples of industrial applications are presented.

scholarly journals Possibility of Human Gender Recognition Using Raman Spectra of Teeth

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3983
Author(s):  
Ozren Gamulin ◽  
Marko Škrabić ◽  
Kristina Serec ◽  
Matej Par ◽  
Marija Baković ◽  
...  
Keyword(s):  
Raman Spectra ◽  
Principal Component ◽  
Support Vector ◽  
Gender Recognition ◽  
Proof Of Concept ◽  
Male And Female ◽  
Tooth Type ◽  
Tooth Apex ◽  
The Difference

Gender determination of the human remains can be very challenging, especially in the case of incomplete ones. Herein, we report a proof-of-concept experiment where the possibility of gender recognition using Raman spectroscopy of teeth is investigated. Raman spectra were recorded from male and female molars and premolars on two distinct sites, tooth apex and anatomical neck. Recorded spectra were sorted into suitable datasets and initially analyzed with principal component analysis, which showed a distinction between spectra of male and female teeth. Then, reduced datasets with scores of the first 20 principal components were formed and two classification algorithms, support vector machine and artificial neural networks, were applied to form classification models for gender recognition. The obtained results showed that gender recognition with Raman spectra of teeth is possible but strongly depends both on the tooth type and spectrum recording site. The difference in classification accuracy between different tooth types and recording sites are discussed in terms of the molecular structure difference caused by the influence of masticatory loading or gender-dependent life events.

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