Preferred Orientations for Sol-Gel Derived Plzt Thin Layers

1993 ◽  
Vol 310 ◽  
Author(s):  
Toshihiko Tani ◽  
Zhengkui Xu ◽  
David A. Payne
Keyword(s):  
Heat Treatment ◽  
Surface Energy ◽  
Sol Gel ◽  
Nucleation And Growth ◽  
Thin Layers ◽  
Energy Conditions ◽  
Chemical Characteristics ◽  
Interfacial Chemistry ◽  
Si Substrates

AbstractPLZT thin layers were deposited onto various substrates by sol-gel methods, and crystallized under different conditions and substrate treatments. Relationships are given for the chemical characteristics of the substrate's surface and the preferred orientations which develop on heat treatment. A preferred (111) orientation always developed for perovskite crystallized on Pt layers which contained Ti on the surface. This was attributed to the formation of Pt3Ti and the role of heteroepitaxial nucleation and growth sites. In addition, a preferred (100) orientation was also obtained on unannealed Pt/Ti/SiO2/Si substrates which were free of Ti on the surface. This was attributed to self-textured growth with flat faces striving for minimum surface energy conditions. The results are discussed in terms of the importance of interfacial chemistry on the control of texture for crystallization of PLZT thin layers on coated substrates.

Sol-Gel Processing of Lithium Niobate Thin-Layers on Silicon

1988 ◽  
Vol 121 ◽  
Author(s):  
Dennis J. Eichorst ◽  
D. A. Payne
Keyword(s):  
Sol Gel ◽  
Solution Chemistry ◽  
Thin Layers ◽  
Processing Route ◽  
High Quality ◽  
Spin Casting ◽  
Evolution Of Structure ◽  
Stable Solutions ◽  
Gel Processing

ABSTRACTSol-gel processing was used for the fabrication of LiNbO3 thin-layers on semiconductors. Two different alkoxide systems were investigated (i.e., ethoxide vs. methoxyethoxide) to determine the role of solution chemistry on the evolution of structure in LiNbO3 layers. An alcohol exchange reaction, which produced lithium niobium methoxyethoxide, proved advantageous with respect to the amount of hydrolysis water content which could be added to give stable solutions. Spin-casting was used for the deposition of thin-layers which crystallized at 500 C on Si. The refractive index of sol-gel derived LiNbO3 was determined to be similar to sputtered or epitaxially grown films. Data are reported for the processing route and the material characteristics. Methoxyethanol based systems appeared to be more forgiving than ethanol based solutions for the fabrication of high-quality thin-layer devices.

Raman and Impedance Spectroscopy of Blend Polycarbonate and Zinc Oxide Layers Grown by Sol-Gel Method

2013 ◽  
Vol 200 ◽  
pp. 22-26 ◽  
Author(s):  
Pawel Popielarski ◽  
Kazimierz Paprocki ◽  
Waclaw Bala ◽  
Agnieszka Banaszak-Piechowska ◽  
Karolina Walczyk ◽  
...  
Keyword(s):  
Sol Gel ◽  
Thin Layers ◽  
X Ray Diffraction ◽  
Confocal Raman Spectroscopy ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Si Substrates ◽  
Surface Spectroscopy ◽  
Different Content

Confocal Raman spectroscopy has been applied to investigate blend polycarbonate and ZnO thin layers with different thicknesses and different content of ZnO. The admittance spectroscopy have been applied to correlation of optical and electrical properties of these layers used in electroluminescence diodes and photovoltaic cells. The I-V (DC and AC) characteristics and thermally stimulated current (TSC) have been applied to the study of the deep levels in ZnO thin films grown by sol-gel method onto Si substrates. The surface spectroscopy morphology of the samples were investigated by scanning microscopy and X ray diffraction.

Heat treatment of spun-on acid-catalyzed sol-gel silica films

1994 ◽  
Vol 9 (3) ◽  
pp. 723-730 ◽  
Author(s):  
T.M. Parrill
Keyword(s):  
Heat Treatment ◽  
Refractive Index ◽  
Spin Coating ◽  
Compressive Strain ◽  
Sol Gel ◽  
Silica Films ◽  
Si Substrates ◽  
Acid Catalyzed ◽  
Film Porosity

SiO2 films, formed by spin coating acid-catalyzed TEOS-based sol-gel on Si substrates, were annealed at 300–1000 °C and analyzed using ellipsometry, FTIR, and in situ stress measurements. Film porosity ranged from an average of 28% before annealing to 7% after annealing 3 h at 1000 °C. Below ≍800 °C, water and silanol removal caused a decrease in refractive index and increase in the in-plane tensile stress. Infrared spectra indicated compressive strain normal to the plane, however. Above ≍800 °C, further densification and structural relaxation occurred. Exposure to H2O also caused relaxation after annealing, as the most compressed Si–O–Si units reacted preferentially with moisture.

On the interfacial chemistry of aryl diazonium compounds in polymer science

2012 ◽  
Vol 66 (5) ◽  
Author(s):  
Zakaria Salmi ◽  
Sarra Gam-Derouich ◽  
Samia Mahouche-Chergui ◽  
Mireille Turmine ◽  
Mohamed Chehimi
Keyword(s):  
Thin Layers ◽  
Polymer Science ◽  
Thin Polymer Films ◽  
Interfacial Chemistry ◽  
New Class ◽  
Thin Polymer ◽  
Grafting From ◽  
Physical And Chemical ◽  
Near Future

AbstractThis review emphasises the role of aryl diazonium compounds as a new class of coupling agents for grafting polymer thin layers onto carbon, diamond, metals, metal oxides, alloys, semi-conductors, ceramics, and polymers. Physical and chemical methods are first reported for anchoring aryl layers to the surfaces, then the review concentrates on the modification of the above substrates by thin polymer films via a range of the “grafting from” and “grafting onto” strategies. Some applications are described which highlight the important role that diazonium salts will continue to play in the near future in the polymer and surface sciences.

Crystallization and Electrical Properties of Bi4TiO12 Films Derived from Bismuth Acetate and Bismuth Nitrate Precursor Solutions

1997 ◽  
Vol 493 ◽  
Author(s):  
Chang Jung Kim ◽  
C. W. Chung ◽  
Kyu Sang Lee
Keyword(s):  
Heat Treatment ◽  
Spin Coating ◽  
Glacial Acetic Acid ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Bismuth Nitrate ◽  
Si Substrates ◽  
Nitrate Precursor ◽  
Coating Method ◽  
Double Heat Treatment

ABSTRACTFerroelectric Bi4Ti3O12 thin films were prepared by the sol-gel method to examine the effect of precursors on the variation of ferroelectric properties. Two kinds of Bi4Ti3O12 sol-gel precursor solutions were synthesized by dissolving bismuth acetate and bismuth nitrate in glacial acetic acid and then adding titanium acetate. The films were deposited on Pt coated Si substrates by the spin-coating method and crystallized by double heat-treatment. The Ps, the Pr, and the Ec values of the film derived from the Bi-acetate were 34.8 μC/cm2, 16.2 μC/cm2, and 128 kV/cm, respectively. The Ps, the Pr, and the Ec of the films from the Bi-nitrate were 14.2 μC/cm2, 5.7 μC/cm2, and 105 kV/cm, respectively. The Bi4T3O12 films prepared from the Bi-acetate revealed better ferroelectricity and resistivity compared to those obtained from the Bi-nitrate.

Residual Stress Effects in Ferroelectric Thin Films

2003 ◽  
Vol 784 ◽  
Author(s):  
T. A. Berfield ◽  
N. R. Sottos ◽  
R. J. Ong ◽  
D. A. Payne
Keyword(s):  
Thin Films ◽  
Residual Stress ◽  
Residual Stresses ◽  
Sol Gel ◽  
Ferroelectric Thin Film ◽  
Thin Layers ◽  
Residual Tensile Stress ◽  
Film Performance ◽  
Si Substrates ◽  
Interface Effects

ABSTRACTRecent developments in soft lithographic patterning enable the integration of functional ceramic thin films on a chip, rather than by adding discrete components to the system. As integrated device applications push the characteristic length scale of materials smaller and smaller, surface and interface effects play an important role, producing significant scientific challenges to the characterization of mechanical properties, performance and reliability. In this paper, we investigate the complex roles of microstructure, interface effects and residual stresses on ferroelectric thin film performance. Pb(Zr0.53Ti0.47)O3 films ranging in thickness from 190 nm to 500 nm were deposited by a sequential build up of sol-gel derived thin layers onto platinized Si substrates. Residual stresses in the films after thermal processing were observed and calculated from laser reflectance measurements of wafer curvature. Field-induced displacements were then measured by interferometric methods for films with well-characterized residual stress states. Results indicate significant increases in film performance with a decrease in measured residual tensile stress.

Microstructural development in sol-gel derived lead zirconate titanate thin films: The role of precursor stoichiometry and processing environment

1996 ◽  
Vol 11 (8) ◽  
pp. 2076-2084 ◽  
Author(s):  
M. J. Lefevre ◽  
J. S. Speck ◽  
R. W. Schwartz ◽  
D. Dimos ◽  
S. J. Lockwood
Keyword(s):  
Thin Films ◽  
Heat Treatment ◽  
Lead Zirconate Titanate ◽  
Single Phase ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Lead Zirconate ◽  
Microstructural Development ◽  
Zirconate Titanate

The role of precursor stoichiometry and local firing environment on the microstructural development of sol-gel derived lead zirconate titanate (PZT) thin films was investigated. Typically, excess Pb is added to films to compensate for PbO volatilization during heat treatment. Here, it is shown that the use of stoichiometric precursors with either a PbO atmosphere powder or a PbO overcoat during the crystallization heat treatment is an attractive and viable alternative method for control of film stoichiometry. Using these approaches, we have fabricated single phase perovskite thin films with microstructures and electrical properties (Pr ∼ 36 μC/cm2 and Ec ∼ 45 kV /cm) comparable to those of films using optimized solution chemistries and excess Pb additions. The potential advantage of increasing PbO partial pressure, or activity, during firing versus excess Pb additions is discussed from the standpoint of a proposed crystallization scenario based on the kinetic competition between Pb loss and the nucleation and growth rates of the perovskite phase.

Strain-induced martensite effects on transgranular carbide precipitation in type 304 stainless steels

1991 ◽  
Vol 49 ◽  
pp. 604-605
Author(s):  
A.H. Advani ◽  
L.E. Murr ◽  
D. Matlock
Keyword(s):  
Heat Treatment ◽  
Grain Boundary ◽  
Stress Corrosion Cracking ◽  
Stainless Steels ◽  
Deformation Twin ◽  
Austenitic Stainless Steels ◽  
Carbide Precipitation ◽  
Strain Induced Martensite ◽  
Type 304

Thermomechanically induced strain is a key variable producing accelerated carbide precipitation, sensitization and stress corrosion cracking in austenitic stainless steels (SS). Recent work has indicated that higher levels of strain (above 20%) also produce transgranular (TG) carbide precipitation and corrosion simultaneous with the grain boundary phenomenon in 316 SS. Transgranular precipitates were noted to form primarily on deformation twin-fault planes and their intersections in 316 SS.Briant has indicated that TG precipitation in 316 SS is significantly different from 304 SS due to the formation of strain-induced martensite on 304 SS, though an understanding of the role of martensite on the process has not been developed. This study is concerned with evaluating the effects of strain and strain-induced martensite on TG carbide precipitation in 304 SS. The study was performed on samples of a 0.051%C-304 SS deformed to 33% followed by heat treatment at 670°C for 1 h.

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