scholarly journals Morphological and Structural Evolution of Chemically Deposited Epitaxially LaNiO3 Thin Films

Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1376
Author(s):  
Mircea Nasui ◽  
Ramona Bianca Sonher ◽  
Ecaterina Ware ◽  
Andrada Daniel ◽  
Traian Petrisor ◽  
...  

We report the preparation and characterization of epitaxial LaNiO3 (LNO) thin films by chemical solution deposition method using lanthanum and nickel acetylacetonates as starting reagents dissolved in propionic acid. In order to obtain further information regarding the decomposition behavior of the film, the precursor solution was dried to obtain the precursor powder, which was investigated by thermal analyses and X-ray diffraction measurements (XRD). The LNO perovskite thin films were deposited by spin coating on SrTiO3(100) single crystal substrates. A detailed study with different crystallization temperatures (600–900 °C) at two different heating ramps (5 and 10 °C/min) was performed. Oriented LaNiO3 thin films with good out-of-plane textures were obtained with optimal surface morphologies.

1999 ◽  
Vol 14 (4) ◽  
pp. 1495-1502 ◽  
Author(s):  
Wataru Sakamoto ◽  
Toshinobu Yogo ◽  
Takae Kuroyanagi ◽  
Shin-ichi Hirano

Crack-free and transparent Sr2KNb5O15 (SKN) thin films have been synthesized by the chemical solution deposition method. A homogeneous and stable precursor solution was prepared via controlling the reaction of metal alkoxides. SKN precursor was found to be the complex alkoxide between Sr[Nb(OEt)6]2 and KNb(OEt)6 with high structural symmetry. SKN powders and thin films on fused silica substrates directly crystallized to the polycrystalline tetragonal tungsten bronze phase at 600 °C. Highly oriented SKN thin films with the tetragonal tungsten bronze phase were fabricated on MgO(100) and Pt(100)/MgO(100) substrates. Two crystal lattice planes of SKN were intergrown at an orientation of 18.5° on MgO(100). The dielectric constant of SKN thin films on Pt(100)/MgO(100) was about 590 at 20 °C at 1 kHz.


1999 ◽  
Vol 14 (11) ◽  
pp. 4395-4401 ◽  
Author(s):  
Seung-Hyun Kim ◽  
D. J. Kim ◽  
K. M. Lee ◽  
M. Park ◽  
A. I. Kingon ◽  
...  

Ferroelectric SrBi2Ta2O9 (SBT) thin films on Pt/ZrO2/SiO2/Si were successfully prepared by using an alkanolamine-modified chemical solution deposition method. It was observed that alkanolamine provided stability to the SBT solution by retarding the hydrolysis and condensation rates. The crystallinity and the microstructure of the SBT thin films improved with increasing annealing temperature and were strongly correlated with the ferroelectric properties of the SBT thin films. The films annealed at 800 °C exhibited low leakage current density, low voltage saturation, high remanent polarization, and good fatigue characteristics at least up to 1010 switching cycles, indicating favorable behavior for memory applications.


2001 ◽  
Vol 688 ◽  
Author(s):  
H. Uchida ◽  
H. Yoshikawa ◽  
I. Okada ◽  
H. Matsuda ◽  
T. Iijima ◽  
...  

AbstractBismuth titanate (Bi4Ti3O12; BIT) -based ferroelectric materials are proposed from the view of the “Site-engineering”, where the Bi-site ions are substituted by lanthanoid ions (La3+ and Nd3+) and Ti-site ions by other ions with higher charge valence (V5+). In the present study, influences of vanadium (V) - substitution for (Bi,M)4Ti3O12 thin films [M = lanthanoid] on the ferroelectric properties are evaluated. V-substituted (Bi,M)4Ti3O12 films have been fabricated using a chemical solution deposition (CSD) technique on the (111)Pt/Ti/SiO2/(100)Si substrate. Remnant polarization of (Bi,La)4Ti3O12 and (Bi,Nd)4Ti3O12 films has been improved by the V-substitution independent of the coercive field. The processing temperature of BLT and BNT films could also be lowered by the V-substitution.


1997 ◽  
Vol 493 ◽  
Author(s):  
Seung-Hyun Kim ◽  
J. G. Hong ◽  
J. C. Gunter ◽  
H. Y. Lee ◽  
S. K. Streiffer ◽  
...  

ABSTRACTFerroelectric PZT thin films on thin RuO2 (10, 30, 50nm)/Pt hybrid bottom electrodes were successfully prepared by using a modified chemical solution deposition method. It was observed that the use of a lOnm RuO2Pt bottom electrode reduced leakage current, and gave more reliable capacitors with good microstructure compare to the use of thicker RuO2/Pt bottom electrodes. Typical P-E hysteresis behavior was observed even at an applied voltage of 3V, demonstrating greatly improved remanence and coercivity. Fatigue and breakdown characteristics, measured at 5V, showed stable behavior, and only below 13-15% degradation was observed up to 1010 cycles. Thicker RuO2 layers resulted in high leakage current density due to conducting lead ruthenate or PZT pyrochlore-ruthenate and a rosette-type microstructure.


1999 ◽  
Vol 606 ◽  
Author(s):  
S. Bhaskar ◽  
S. B. Majumder ◽  
P. S. Dobal ◽  
R. S. Katiyar ◽  
A. L. M. Cruz ◽  
...  

AbstractIn the present work we have optimized the process parameters to yield homogeneous, smooth ruthenium oxide (RuO2) thin films on silicon substrates by a solution deposition technique using RuCl3.×.H2O as the precursor material. Films were annealed in a temperature range of 300°C to 700°C, and it was found that RuO2 crystallizes at a temperature as low as 400°C. The crystallinity of the films improves with increased annealing temperature and the resistivity decreases from 4.86µΩ-m (films annealed at 400°C) to 2.94pµΩ (films annealed at 700°C). Ageing of the precursor solution has a pronounced effect on the measured resistivities of RuO2 thin films. It was found that the measured room temperature resistivities increases from 2.94µΩ-m to 45.7µΩ-m when the precursor sol is aged for aged 60 days. AFM analysis on the aged films shows that the grain size and the surface roughness of the annealed films increase with the ageing of the precursor solution. From XPS analysis we have detected the presence of non-transformed RuCl3 in case of films prepared from aged solution. We propose, that solution ageing inhibits the transformation of RuCl3 to RuO2 during the annealing of the films. The deterioration of the conductivity with solution ageing is thought to be related with the chloride contamination in the annealed films.


1999 ◽  
Vol 14 (10) ◽  
pp. 4004-4010 ◽  
Author(s):  
J. H. Kim ◽  
F. F. Lange

Epitaxial PbZr0.5Ti0.5O3 (PZT) thin films were grown on (001) LaAlO3 substrates (∼6.1% lattice mismatch) by the chemical solution deposition method. The sequence of epitaxy during heating between 375 and 700 °C/1h was characterized by x-ray diffraction and transmission electron microscopy. At approximately 375 °C/1h, a nanocrystalline metastable fluorite phase of PZT was formed from the pyrolyzed amorphous precursor. At higher temperatures (400–425 °C/1h), thermodynamically stable PZT crystallites were first observed at the interface; with increasing higher temperatures, these nuclei grew across the interface and through the film toward the surface by consuming the metastable nanocrystalline fluorite grains. PZT thin films annealed above ∼500 °C/1h were observed to be dense with an epitaxial orientation relationship of [100](001)PZT‖[100](001)LAO. The metastable nanocrystalline fluorite to the stable single-crystal perovskite transformation gives an extra driving force by providing an additional decrease in free energy in addition to a driving force from the elimination of grain boundary area for epitaxy.


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