Ferroelectric Bi4Ti3O12–SrBi4Ti4O15 Intergrowth Thin Films Prepared by Pulsed Laser Deposition

2002 ◽  
Vol 748 ◽  
Author(s):  
Akira Shibuya ◽  
Minoru Noda ◽  
Masanori Okuyama

ABSTRACTC axis-oriented Bi4Ti3O12–SrBi4Ti4O15 (B IT-SB Ti) intergrowth epitaxial ferroelectric thin films have been grown by pulsed laser deposition (PLD) method on MgO (001) and SrTiO3 (001) substrates. The epitaxial growth of BIT-SBTi intergrowth thin films were confirmed by X-ray diffraction (XRD) θ-2θ scan, pole figure plots and reciprocal space mappings. The c axis lattice constant of the BIT-SBTi intergrowth thin film is very close to that of made up of regular stacking of one-halves of the unit cells of Bi4Ti3O12 (3.296 nm) and SrBi4Ti4O15 (4.189 nm). The annealed BIT-SBTi thin film on Pt/Ti/SiO2/Si substrate shows intergrowth structure, too, and exhibits superior ferroelectricity that the values of 2Pr and 2Ec are 32.0 μC/cm2 and 190 kV/cm, respectively. The annealed BIT-SBTi film shows that the degradation of switching charge after 1×1010 switching cycles was 16.5%. This ferroelectric enhancement is attributed to strain of pseudo-perovskite layers interacting through Bi2O2 layer. The dielectric constant and dielectric loss of the annealed BIT-SBTi film were 433 and 0.037, respectively.

2015 ◽  
Vol 231 ◽  
pp. 19-24 ◽  
Author(s):  
Agnieszka Kopia ◽  
Łukasz Cieniek ◽  
Kazimierz Kowalski ◽  
Jan Kusiński

The aim of the research was to investigate the influence of strontium on the structure thin films La1-x SrxCoO3 (x=0; 0.1, 0.2). The LaCoO3 and LaCoO3 doped by Sr films were grown by pulsed laser deposition (PLD) on Si [100] substrate using an Excimer KrF (= 248 nm). To characterize the structure and morphology of the thin films were used the SEM, AFM and XRD methods. X-Ray Diffraction analysis showed only LaCoO3 phase in the thin film not doped andLa0.1Sr0.9CoO3 and La0.2Sr0.8CoO3 phases in thin films doped by Sr. The crystallites size, calculated by Williamson-Hall plots, was smaller for films doped by Sr. The surface of the thin films was free from the drops. SEM analysis showed change of the shape of thin films as a result of doping by Sr. Highly developed layer surface was observed using the AFM microscope for thin films doped by Sr.


2010 ◽  
Vol 123-125 ◽  
pp. 375-378 ◽  
Author(s):  
Ram Prakash ◽  
Shalendra Kumar ◽  
Chan Gyu Lee ◽  
S.K. Sharma ◽  
Marcelo Knobel ◽  
...  

Ce1-xFexO2 (x=0, 0.01, 0.03 and 0.0 5) thin films were grown by pulsed laser deposition technique on Si and LaAlO3 (LAO) substrates. These films were deposited in vacuum and 200 mTorr oxygen partial pressure for both the substrates. These films were characterized by x-ray diffraction XRD and Raman spectroscopy measurements. XRD results reveal that these films are single phase. Raman results show F2g mode at ~466 cm-1 and defect peak at 489 cm-1 for film that deposited on LAO substrates, full width at half maximum (FWHM) is increasing with Fe doping for films deposited on both the substrates.


2000 ◽  
Vol 655 ◽  
Author(s):  
Masanori Okuyama ◽  
Toshiyuki Nakaiso ◽  
Minoru Noda

AbstractSr2(Ta1划x, Nbx)2O7(STN) ferroelectric thin films have been prepared on SiO2/Si(100) substrates by the pulsed laser deposition (PLD) method. Preferential (110) and (151)-oriented STN thin films are deposited at a low temperature of 600°C in N2O ambient gas at 0.08 Torr. A counterclockwise C-V hysteresis was observed in the metal-ferroelectric-insulator-semiconductor (MFIS) structure using Sr2(Ta0.7, Nb0.3)2O7 on SiO2/Si deposited at 600°C. Memory window in the C-V curve spreads symmetrically towards both positive and negative directions when applied voltage increases and the window does not change in sweep rates ranging from 0.1 to 4.0×103 V/s. The C-V curve of the MFIS structure does not degrade after 1010 cycles of polarization reversal. The gate retention time is about 3.0×103 sec when the voltages and time of write pulse are ±15V and 1.0 sec, respectively, and hold bias was -0.5 V.


Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 954
Author(s):  
Anna Cyza ◽  
Łukasz Cieniek ◽  
Tomasz Moskalewicz ◽  
Wojciech Maziarz ◽  
Jan Kusiński ◽  
...  

The aim of the presented investigations was to deposit the thin films La1−xSrxFeO3 (x = 0, 0.1, 0.2) on (100) Si substrate by using the Pulsed Laser Deposition (PLD) method. Structure was exanimated by using XRD, SEM, AFM, TEM and XPS methods. The catalytic properties were analyzed in 4 ppm acetone atmosphere. The doping of Sr thin films La1−xSrxFeO3 (x = 0, 0.1, 0.2) resulted in a decrease in the size of the crystallites, the volume of the elemental cell and change in the grain morphology. In the LaFeO3 and La0.9Sr0.1FeO3, clusters around which small grains grow are visible in the structure, while in the layer La0.8Sr0.2FeO3, the visible grains are elongated. The TEM analysis has shown that the obtained thin films had a thickness in the range 150–170 nm with triangular or flat column ends. The experiment performed in the presence of gases allowed us to conclude that the surfaces (101/020) in the triangle-shaped columns and the plane (121/200) faces in flat columns were exposed to gases. The best properties in the presence of CH3COCH3 gas were noted for LaFeO3 thin film with triangle columns ending with orientation (101/020).


2005 ◽  
Vol 19 (01n03) ◽  
pp. 533-535
Author(s):  
J. H. HAO ◽  
J. GAO

We have developed a process to grow SrTiO 3 ( STO ) thin films showing single (110) orientation directly on Si by means of pulsed laser deposition technique. The growth of STO films directly on Si has been described. The crystallinity of the grown STO films was characterized by X-ray diffraction analysis of θ-2θ scan and rocking curve. Our results may be of interest for better understanding of the growth based on the perovskite oxide thin films on silicon materials.


2011 ◽  
Vol 1292 ◽  
Author(s):  
Nobuyuki Iwata ◽  
Mark Huijben ◽  
Guus Rijnders ◽  
Hiroshi Yamamoto ◽  
Dave H. A. Blank

ABSTRACTThe CaFeOX(CFO) and LaFeO3(LFO) thin films as well as superlattices were fabricated on SrTiO3(100) substrates by pulsed laser deposition (PLD) method. The tetragonal LFO film grew with layer-by-layer growth mode until approximately 40 layers. In the case of CFO, initial three layers showed layer-by-layer growth, and afterward the growth mode was transferred to two layers-by-two layers (TLTL) growth mode. The RHEED oscillation was observed until the end of the growth, approximately 50nm. Orthorhombic twin CaFeO2.5 (CFO2.5) structure was obtained. However, it is expected that the initial three CFO layers are CaFeO3 (CFO3) with the valence of Fe4+. The CFO and LFO superlattice showed a step-terraces surface, and the superlattice satellite peaks in a 2θ-θ and reciprocal space mapping (RSM) x-ray diffraction (XRD) measurements, indicating that the clear interfaces were fabricated.


2011 ◽  
Vol 47 (4) ◽  
pp. 415-422 ◽  
Author(s):  
G. Balakrishnan ◽  
P. Kuppusami ◽  
S. Murugesan ◽  
E. Mohandas ◽  
D. Sastikumar

2016 ◽  
Vol vol1 (1) ◽  
Author(s):  
Billal Allouche ◽  
Yaovi Gagou ◽  
M. El Marssi

By pulsed laser deposition, lead potassium niobate Pb2KNb5O15 was grown on (001) oriented Gd3Ga5O12 substrate using a platinum buffer layer. The PKN thin films were characterized by X-Ray diffraction and Scanning Electron Microscopy (SEM). The dependence of their structural properties as a function of the deposition parameters was studied. It has been found that the out of plane orientation of PKN film depends on the oxygen pressure used during the growth. Indeed, PKN thin film is oriented [001] for low pressure and is oriented [530] for high pressure. For these two orientations, the crystalline quality of PKN film was determined using omega scans.


2003 ◽  
Vol 780 ◽  
Author(s):  
V. Craciun ◽  
D. Craciun ◽  
J. M. Howard ◽  
R. K. Singh

AbstractZrC thin films were grown on Si substrates by the pulsed laser deposition (PLD) technique. X- ray photoelectron spectroscopy, x-ray diffraction and reflectivity, variable angle spectroscopic ellipsometry, and four point probe measurements were used to investigate the composition, density, thickness, surface morphology, optical and electrical properties of the grown structures. It has been found that crystalline films could be grown only by using fluences above 6 J/cm2 and substrate temperatures in excess of 500 °C. For a fluence of 10 J/cm2 and a substrate temperature of 700 °C, highly (100)-textured ZrC films exhibiting a cubic structure (a=0.469 nm) and a density of 6.7 g/cm3 were deposited. The use of a low-pressure atmosphere of C2H2 had a beneficial effect on crystallinity and stoichiometry of the films. All films contained high levels of oxygen contamination, especially in the surface region, because of the rather reactive nature of Zr atoms.


2006 ◽  
Vol 11-12 ◽  
pp. 311-314 ◽  
Author(s):  
Hiroki Asami ◽  
Jun Inoue ◽  
M. Hirai ◽  
Tsuneo Suzuki ◽  
Tadachika Nakayama ◽  
...  

Chromium magnesium oxynitride ((Cr,Mg)(N,O)) thin films have been prepared by pulsed laser deposition (PLD) method with changing the surface area ratio of Mg target (SR) from 0 to 100 %. As a result of the analysis by energy dispersive X-ray spectroscopy (EDX), it was found that magnesium content in the total metallic elements (Cr1-x, Mgx) are controlled by changing SR from 0 to 100 % to be the x ranging from 0 to 1.0. Since the crystal structure of main phase in all thin films was found to be NaCl type, the XRD results showed that the thin films were mainly consisted of (Cr,Mg)(N,O). The hardness of (Cr,Mg)(N,O) thin films were increased almost linearly up to SR = 50 %, above which it decreases rapidly. The maximum Vickers hardness (HV) of 3600 was obtained for the thin film which was prepared by SR = 50 %, and the minimum HV of 1650 was obtained for the thin film which was prepared by SR = 100 %.


Sign in / Sign up

Export Citation Format

Share Document