Composite BST/MgO thin films for microwave tunable devices

2000 ◽  
Vol 656 ◽  
Author(s):  
T. V. Rivkin ◽  
J. D. Perkins ◽  
P. A. Parilla ◽  
D. S. Ginley ◽  
C. M. Carlson ◽  
...  
Keyword(s):  
Thin Films ◽  
Substrate Surface ◽  
Lattice Parameter ◽  
Out Of Plane ◽  
Spatial Redistribution ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Mgo Substrate ◽  
Deposited Films ◽  
Post Deposition

ABSTRACTComposite thin films of 60 wt% Ba0.6Sr0.4TiO3 and 40 wt% MgO were produced by Pulsed Laser Deposition. The biaxial texture of the BST component on the MgO substrate has been established with XRD. All as-deposited films had an enlarged BST out-of-plane lattice parameter. A more relaxed lattice constant as well as higher degree of texture has been obtained in the films deposited at higher temperature and lower deposition rate. Post-deposition annealing in flowing oxygen results in a further relaxation and alignment of the BST lattice. The as-deposited films were not tunable at room temperature. The greatest dielectric tuning was achieved in films annealed at 1200 °C. The observed difference in tunability for the films annealed at different temperatures may result from a spatial redistribution of BST material on the substrate surface during annealing.

The Structure and Electric Field Dependent Dielectric Properties of Annealed Sr1−xBaxTio3 Ferroelectric Thin Films

1995 ◽  
Vol 401 ◽  
Author(s):  
L.A. Knauss ◽  
J.M. Pond ◽  
J.S. Horwitz ◽  
C.H. Mueller ◽  
R.E. Treece ◽  
...  
Keyword(s):  
Thin Films ◽  
Dielectric Properties ◽  
Single Phase ◽  
Pulsed Laser ◽  
Lattice Parameter ◽  
Laser Deposition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Deposited Films ◽  
Post Deposition

AbstractThe effect of a post deposition anneal on the structure and dielectric properties of epitaxial Sr1−x, BaxTiO3 (SBT) thin films with x = 0.35, 0.50 and 0.60 has been measured. The films were grown by pulsed laser deposition on LaAlO3(001) substrates at 750°C in 350 mTorr of oxygen. The asdeposited films were single phase, (001) oriented with 0)-scan widths for the (002) reflection between 0.160 and 0.50'. The dielectric properties of the as-deposited films exhibit a broad temperature dependence and a peak which is as much as 50 K below the peak in bulk SBT. Also, the lattice parameter, as measured by x-ray diffraction, of the as-deposited films was larger than the bulk indicating strain in the films. The as-deposited films were annealed for 8 hours at 900°C in oxygen. The dielectric properties of the annealed films were closer to that of bulk SBT and the lattice parameter was closer to the bulk lattice parameter indicating a reduction of strain. Annealing of as-deposited films also resulted in an increased dielectric tuning without increased dielectric loss.

Structural characterization of laser ablated epitaxial (Ba0.5Sr0.5)TiO3 thin films on MgO(001) by synchrotron x-ray scattering

1999 ◽  
Vol 14 (7) ◽  
pp. 2905-2911 ◽  
Author(s):  
Sangsub Kim ◽  
Tae Soo Kang ◽  
Jung Ho Je
Keyword(s):  
Thin Films ◽  
Early Stage ◽  
Lattice Parameter ◽  
Normal Direction ◽  
X Ray ◽  
X Ray Scattering ◽  
Surface Normal ◽  
Out Of Plane ◽  
Axis Parallel ◽  
Ray Scattering

Epitaxial (Ba0.5Sr0.5) TiO3 thin films of two different thickness (∼25 and ∼134 nm) on MgO(001) prepared by a pulsed laser deposition method were studied by synchrotron x-ray scattering measurements. The film grew initially with a cube-on-cube relationship, maintaining it during further growth. As the film grew, the surface of the film became significantly rougher, but the interface between the film and the substrate did not. In the early stage of growth, the film was highly strained in a tetragonal structure (c/a = 1.04) with the longer axis parallel to the surface normal direction. As the growth proceeded further, it relaxed to a cubic structure with the lattice parameter near the bulk value, and the mosaic distribution improved significantly in both in- and out-of-plane directions. The thinner film (∼25 nm) showed only one domain limited mainly by the film thickness, but the thicker film (∼134 nm) exhibited three domains along the surface normal direction.

scholarly journals Elaboration of nitride thin films by reactive sputtering

2006 ◽  
Vol 59 (2) ◽  
pp. 225-232 ◽  
Author(s):  
Pierre Yves Jouan ◽  
Arnaud Tricoteaux ◽  
Nicolas Horny
Keyword(s):  
Thin Films ◽  
Compressive Stress ◽  
Bias Voltage ◽  
Substrate Surface ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
A Value ◽  
Dc Reactive Magnetron Sputtering ◽  
Nitrogen Contents

The aim of this paper is first a better understanding of DC reactive magnetron sputtering and its implications, such as the hysteresis effect and the process instability. In a second part, this article is devoted to an example of specific application: Aluminium Nitride. AlN thin films have been deposited by reactive triode sputtering. We have studied the effect of the nitrogen contents in the discharge and the RF bias voltage on the growth of AlN films on Si(100) deposited by triode sputtering. Stoichiometry and crystal orientation of AlN films have been characterized by means of Fourier-transform infrared spectroscopy, X-ray diffraction and secondary electron microscopy. Dense and transparent AlN layers were obtained at high deposition rates. These films have a (002) orientation whatever the nitrogen content in the discharge, but the best crystallised ones are obtained at low value (10%). A linear relationship was observed between the AlN lattice parameter "c" (perpendicular to the substrate surface) and the in-plane compressive stress. Applying an RF bias to the substrate leads to a (100) texture, and films become amorphous. Moreover, the film's compressive stress increases up to a value of 8GPa before decreasing slowly as the bias voltage increases.

Effect of Annealing on Microstructure of Hydroxyapatite Coatings and their Behaviours in Simulated Body Fluid

2014 ◽  
Vol 922 ◽  
pp. 657-662 ◽  
Author(s):  
Sharidah Azuar Abdul Azis ◽  
John Kennedy ◽  
Peng Cao
Keyword(s):  
Heat Treatment ◽  
Simulated Body Fluid ◽  
Body Fluid ◽  
Ion Beam ◽  
Apatite Formation ◽  
Ion Beam Sputtering ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Xrd Patterns ◽  
Post Deposition

In this study, hydroxyapatite (HA) coatings on Ti6Al4V substrate were deposited using an ion beam sputtering technique. Owing to its medical applications, the crystalline phases present in the HA must be controlled. This study investigated the effect of post-deposition heat treatment at different temperatures and evaluated the microstructure of the HA coatings and their behaviours in simulated body fluid (SBF). The post-deposition treatment of the as-deposited samples was carried out in an air-circulated furnace at a temperature between 3000C and 6000C. The XRD patterns reveal that the minimum temperature to transform the HA coating from amorphous to crystalline phase is 4000C. A higher temperature at 6000C leads to a growth of the crystalline HA phases. Fourier transform infrared spectroscopy (FTIR) measurements show the existence of hydroxyl and PO-bonds in all coatings and the amounts varied with temperature. Atomic Force Microscopy (AFM) study suggests that the nanostructured crystalline HA starts to grow at 4000C and becomes more obvious at a higher temperature of 6000C. The simulated body fluid (SBF) test reveals that better apatite formation with post deposition heat treatment at 6000C would potentially enhance the formation of new bone (osseointegration).

Influence of RTA Treatment on the Properties of ZnO-CeO2 Dielectric Films

2014 ◽  
Vol 787 ◽  
pp. 232-235 ◽  
Author(s):  
Ching Fang Tseng ◽  
Ren Ya Yang ◽  
Chien Hua Chen
Keyword(s):  
Annealing Temperature ◽  
Substrate Surface ◽  
Sol Gel ◽  
Dielectric Films ◽  
Electrical Characteristics ◽  
Rapid Thermal Annealing Process ◽  
Heat Treated ◽  
Different Temperatures ◽  
Thermal Annealing Process ◽  
Deposited Films

The electrical and physical properties of ZnO-CeO2 thin films on n-type Si (100) substrates have been examined by sol-gel method. In addition, the structures were heat treated at different temperatures from 600 to 700oC using the RTA (Rapid Thermal Annealing) process and investigated the influence of RTA effect on their properties. The diffraction pattern showed that the deposited films exhibited a polycrystalline microstructure. All films exhibited ZnO-CeO2 peaks orientation perpendicular to the substrate surface and the grain size with the dependent on annealing temperature. The dependence of the physical and electrical characteristics on various annealing temperatures was investigated.

Effect of Deposition Time on Structure of TiAlN Thin Films Deposited by Reactive DC Magnetron Co-Sputtering

2017 ◽  
Vol 866 ◽  
pp. 318-321 ◽  
Author(s):  
Nirun Witit-Anun ◽  
Adisorn Buranawong
Keyword(s):  
Thin Films ◽  
Elemental Composition ◽  
Deposition Time ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Titanium Aluminum ◽  
Titanium Aluminum Nitride ◽  
Deposited Films ◽  
Section Analysis

Titanium aluminum nitride (TiAlN) thin films were deposited by reactive DC magnetron co-sputtering technique on Si substrate. The effect of deposition time on the structure of the TiAlN films was investigated. The crystal structure, surface morphology, thickness and elemental composition were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) technique, respectively. The results showed that, all the as-deposited films were formed as a (Ti,Al)N solid solution. The as-deposited thin films exhibited a nanostructure with a crystallite size of less than 30 nm. The film thickness increase from 115 nm to 329 nm, while the lattice parameter decrease from 4.206 Å to 4.196 Å, with increasing of the deposition time. Cross section analysis by FE-SEM showed compact columnar and dense morphology as a result of increasing the deposition time. The elemental composition of the as-deposited films varied with the deposition time.

scholarly journals EFFECT OF MOLARCONCENTRATION OF PRECURSORSON THE STRUCTURAL, OPTICALAND ELECTRICAL PROPERTIES OF CUALS2 THIN FILMS PREPARED BY CHEMICAL BATH DEPOSITION TECHNIQUE

2021 ◽  
Vol 03 (03) ◽  
pp. 92-102
Author(s):  
Bilal Y. TAHER ◽  
Ahmad S. AHMAD
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Chemical Bath Deposition ◽  
Ph Value ◽  
Substrate Surface ◽  
Concentration Field ◽  
Molar Concentration ◽  
Ultraviolet Region ◽  
Average Grain Size ◽  
Deposited Films

CuAlS2 thin films have been prepared on glass substrates by Chemical bath deposition (CBD) technique at a substrate temperature (Ts) 75C, pH value 10.5.The Effect of three different molar concentration (0.05, 0.025, 0.1), (0.075, 0.0375, 0.15), and (0.1, 0.05, 0.2) M of precursors of (CuSO4.5H2O, Al2(SO4)3.16H2O, and (NH2)2CS), respectively on the structural, optical and electrical properties of deposit thin films was studied. The X-ray diffraction (XRD) patterns showed that the films have an amorphous structure with simple enhancement in the structure of the films with the higher molar concentration. Field emission scanning electron microscopy (FESEM) analysis of thin films showed that the deposited films were a good surface morphology, homogenous and uniform spherical nanoparticles over the substrate surface with very little agglomerated particles with average grain size in the range (45 to 72 nm) increase with increasing molar concentration of precursors. Atomic force microscopy (AFM) showed the topography of deposited films has nanoparticles with structures like conical and lobes shape, with the average grain sizes, root mean square (rms) roughness, and surface roughness increase with increasing molar concentration of precursors. The optical analysis by UV-Vis Spectrophotometer showed high absorption in the ultraviolet region, with absorption edge and direct energy gaps (3.5 to 4eV) variedat different molar concentrations of precursors. The electrical results from Hall effect measurements showed that the values of resistivity, conductivity, mobility, and carrier concentration were varied in range (0.046 to 0.594ohm.cm), (1.86 to 21.7(ohm.cm)-1), (301to 1510 cm2/V.S), and (3.29×1016 to 1.46×1017 cm-3), respectively .Also,n-type conductivity was investigated for all prepared film sat different molar concentration of precursors. The obtained results of the prepared CuAlS2 thin films can be suitable in many optoelectronics applications.

Effect of Annealing Treatments on Mg(Zr0.05Ti0.95)O3 Thin Films by Sol-Gel Method

2011 ◽  
Vol 216 ◽  
pp. 518-522
Author(s):  
Ching Fang Tseng ◽  
Chun Hung Lai ◽  
Chih Wen Lee
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Annealing Temperature ◽  
Substrate Surface ◽  
Sol Gel ◽  
Gel Method ◽  
Sol Gel Method ◽  
Annealing Temperatures ◽  
Polycrystalline Microstructure ◽  
Deposited Films

Dielectric, Optical properties and microstructures of Mg(Zr0.05Ti0.95)O3 thin films prepared by sol-gel method on n-type Si(100) substrates at different annealing temperatures have been investigated. The selected-area diffraction pattern showed that the deposited films exhibited a polycrystalline microstructure. All films exhibited Mg(Zr0.05Ti0.95)O3 peaks orientation perpendicular to the substrate surface and the grain size with the increase in the annealing temperature. A dielectric constant of 7.4 and an optical bandgap of 3.7 were obtained for the prepared films.

Crystallization of yttrium-iron garnet (YIG) in thin films: Nucleation and growth aspects

2007 ◽  
Vol 1036 ◽  
Author(s):  
Michael V. Zaezjev ◽  
Manda Chandra Sekhar ◽  
Marcello Ferrera ◽  
Luca Razzari ◽  
Barry M Holmes ◽  
...  
Keyword(s):  
Thin Films ◽  
Yttrium Iron Garnet ◽  
Single Phase ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Yttrium Iron ◽  
Iron Garnet ◽  
Parasitic Phase ◽  
Deposited Films ◽  
Post Deposition

AbstractWe have studied the crystallization of the yttrium - iron garnet (Y3Fe5O12, YIG) polycrystalline phase in thin films fabricated by means of pulsed laser deposition . Films were deposited on MgO substrates in vacuum, in argon, and in oxygen. A subsequent post-deposition heat treatment (annealing) was done at 800°C in air. We have shown that the crystallization of YIG was precluded by co-existent parasitic phases present in the as-deposited films. Specifically, the growth of the parasitic phase needs to be suppressed in order to get a single-phase polycrystalline YIG. Lowering the substrate temperature has been shown to be a simple and efficient way to suppress the growth of parasitic phase and to obtain good quality YIG films after thermal treatment. This procedure has been demonstrated to be successful even when the YIG films were grown in vacuum and their composition was significantly out of stoichiometry.

Epitaxy, microstructure, and processing-structure relationships of TiO2 thin films grown on sapphire (0001) by MOCVD

1993 ◽  
Vol 8 (10) ◽  
pp. 2634-2643 ◽  
Author(s):  
H.L.M. Chang ◽  
T.J. Zhang ◽  
H. Zhang ◽  
J. Guo ◽  
H.K. Kim ◽  
...  
Keyword(s):  
Thin Films ◽  
Single Crystal ◽  
Film Growth ◽  
Growth Parameters ◽  
Substrate Surface ◽  
Growth Conditions ◽  
Organic Chemical ◽  
Tio2 Thin Films ◽  
Growth Plane ◽  
Deposited Films

TiO2 thin films have been deposited on sapphire (0001) substrates under various conditions by metal-organic chemical vapor deposition. The structural properties of the deposited films were characterized by x-ray diffraction and transmission electron microscopy. The important growth parameters were found to be the deposition temperature and the deposition rate. The ranges studied for the two parameters were 400 to 850 °C and 10 to 120 Å/min, respectively. Depending on the growth conditions, most of the deposited films were either single-phase anatase or rutile, or a mixture of the two. These films were all epitaxial, but none of them were single-crystal films. Three distinct epitaxial relationships were observed between the films and the substrates, and, depending on the growth conditions, a deposited film can contain one, two, or all three of them. The fact that the films we obtained, although epitaxial, were never single crystal is explained based on the consideration of the difference in the rotational symmetries of the substrate surface and the film growth plane. We believe that it should be generally true that, in heteroepitaxial growth, a true single-crystal film can never be obtained as long as the point symmetry group of the substrate surface is not a subgroup of that of the film growth plane.

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