scholarly journals Effect of thermal treatment on structure and leakage current of Na0.5Bi0.5TiO3 thin films

2018 ◽  
Vol 26 (1) ◽  
pp. 53-56
Author(s):  
T. V. Kruzina ◽  
S. A. Popov ◽  
Yu. N. Potapovich ◽  
A. S. Rutskyi

Na0.5Bi0.5TiO thin films were grown on heated to 200°С Pt/TiO2/SiO2/Si substrates by ex-situ method with high-frequency (13.56 MHz) magnetron deposition. Thermal treatment of the films was carried out at 650°С, 700°С and 800°С. X-ray diffraction investigations showed the films were poly-crystalline and contained additional phase. In the films annealed at 700°C two dominating conduction mechanisms were observed: ohmic at the fields Е < 8 kV/cm and Schottky emission in the field range of 30 – 70 kV/cm. It is also observed that the increase of the film annealing temperature to 800°С leads to the increase of leakage currents. It is assumed that high values of the leakage currents were attributed to the presence of both structure defects and additional unknown phase.

2020 ◽  
Vol 28 (1) ◽  
pp. 33-38
Author(s):  
T. V. Kruzina ◽  
S. A. Popov ◽  
Yu. N. Potapovich ◽  
S. I. Ryabtsev ◽  
A. S. Rutskiy

Some special features of Na0.5Bi0.5TiO3 (NBT) thin films preparation process and electrical properties of the films are presented. The NBT films were grown on both Pt/sitall and Pt/TiO2/SiO2/Si substrates by ex-situ method with high-frequency (13.56 MHz) magnetron deposition. Thermal treatment of the films was carried out in the temperature range 550°С – 700°С in air. Obtained X-ray diffraction data show that annealing at 700°C promotes crystallization of NBT films in ferroelectric perovskite phase with minor inclusions of pyrochlore phase. Dielectric hysteresis (P-E) loops in electric field of 90 kV/cm (50 Hz) and the current density-electric field (J-E) characteristics of the films are investigated. It is found that densities of leakage currents in weak fields depend on the film substrate and are significantly lower for the films deposited on the Pt/sitall structure (~6.9 10-10 A/cm2) in comparison with the films deposited on the Pt/TiO2/SiO2/Si structure (~10-6 A/cm2). The main mechanisms of leakage currents in thin NBT ferroelectric films and the role of structural defects in charge transfer process are discussed.


2010 ◽  
Vol 434-435 ◽  
pp. 263-266
Author(s):  
Chien Chen Diao ◽  
Chia Ching Wu ◽  
Cheng Fu Yang ◽  
Chao Chin Chan

In this study, 0.95 (Na0.5Bi0.5)TiO3-0.05 BaTiO3 + 1 wt% Bi2O3 (NBT-BT3) composition sintered at 1200oC for 2h is used as target to deposit the NBT-BT3 thin films. The excess 1wt% Bi2O3 is used to compensate the vaporization of Bi2O3 during the deposition process. Ferroelectric NBT-BT3 thin films are deposited on SiO2/Si and Pt/Ti/SiO2/Si substrates using RF magnetron sputter method using the ceramic target fabricated by ourselves. After depositing under the optimal parameters, the thin films are then heated by a conventional thermal annealing (CFA) process conducted in air at temperatures ranging from 600- 800oC for 60min. The morphologies of NBT- BT3 thin films are observed using SEM the crystalline structures of NBT-BT3 thin films are investigated using XRD patterns. The large memory window and stable leakage current density examination reveals that NBT-BT3 thin films annealed on 600oC are better than other thin films under different CTA temperatures. Finally, the top view and cross-sectional images of SEM, memory windows, leakage currents and polarization characteristics of NBT-BT3 thin films are also well developed.


2018 ◽  
Vol 6 (24) ◽  
pp. 11496-11506 ◽  
Author(s):  
Paul Pistor ◽  
Thomas Burwig ◽  
Carlo Brzuska ◽  
Björn Weber ◽  
Wolfgang Fränzel

We present the identification of crystalline phases by in situ X-ray diffraction during growth and monitor the phase evolution during subsequent thermal treatment of CH3NH3PbX3 (X = I, Br, Cl) perovskite thin films.


2013 ◽  
Vol 669 ◽  
pp. 181-184
Author(s):  
Nan Ding ◽  
Li Ming Xu ◽  
Bao Jia Wu ◽  
Guang Rui Gu

Zinc oxide (ZnO) films were prepared on Si substrates and then aluminum nitride (AlN) films were deposited on ZnO films by radio frequency (RF) magnetron sputtering. The crystal orientation, crystallite structure and surface morphology of AlN/ZnO films were characterized by X-ray diffraction (XRD), Raman spectrum and scanning electron microscopy (SEM). It was indicated that the AlN films were closely deposited on the ZnO film and had good crystallinity. Moreover, about 1μm-sized crystal particles with high c-axial orientation distributed uniformly on the AlN/ZnO film surface. It was indicated that ZnO could be a promising candidate as buffer layer for preparation of AlN thin films.


2001 ◽  
Vol 15 (17n19) ◽  
pp. 769-773 ◽  
Author(s):  
M. GARCIA-ROCHA ◽  
A. CONDE-GALLARDO ◽  
I. HERNANDEZ-CALDERON ◽  
R. PALOMINO-MERINO

In this work we show the results on tile growth and optical characterization of TiO 2 thin films doped with Eu atoms. Eu:TiO2 films were grown at room temperature with different Eu concentrations by sol-gel on Si Corning glass substrates. A different crystalline structure is developed for the films deposited on Corning glass than those deposited on Si as observed from x-ray diffraction experiments. Room and low temperature photoluminescence (PL) was measured by using two different lines (325 and 442 nm) of a HeCd laser. A strong PL signal associated to the 5 D 0→7 F 2 transition from Eu +3 was observed. A better emission was obtained from those films deposited on Si substrates, Finally, the evolution of the PL signal is studied when the samples are annealed at different temperatures in O 2 atmosphere.


1991 ◽  
Vol 05 (18) ◽  
pp. 1203-1211 ◽  
Author(s):  
C. ATTANASIO ◽  
L. MARITATO ◽  
A. NIGRO ◽  
S. PRISHEPA ◽  
R. SCAFURO

BSCCO thin films with T c (R = 0) higher than 80 K have been routinely prepared using a simple and reliable technique in which we completely electron beam evaporated weighted amounts of bulk pellets. The films were grown on MgO single crystal (100) substrates and showed, after an ex-situ annealing at high temperatures (840–880° C) for several hours, a strong preferential orientation with the c-axis perpendicular to the plane of the substrate. The films were characterized by Θ − 2Θ X-ray diffraction and EDS analysis and by paraconductivity and critical current measurements.


2012 ◽  
Vol 545 ◽  
pp. 290-293
Author(s):  
Maryam Amirhoseiny ◽  
Hassan Zainuriah ◽  
Ng Shashiong ◽  
Mohd Anas Ahmad

We have studied the effects of deposition conditions on the crystal structure of InN films deposited on Si substrate. InN thin films have been deposited on Si(100) substrates by reactive radio frequency (RF) magnetron sputtering method with pure In target at room temperature. The nitrogen gas pressure, applied RF power and the distance between target and substrate were 2×10-2 Torr, 60 W and 8 cm, respectively. The effects of the Ar–N2 sputtering gas mixture on the structural properties of the films were investigated by using scanning electron microscope, energy-dispersive X-ray spectroscopy, atomic force microscopy and X-ray diffraction techniques.


1998 ◽  
Vol 541 ◽  
Author(s):  
Nan Chen ◽  
G. R. Bai ◽  
O. Auciello ◽  
R. E. Koritala ◽  
M. T. Lanagan

AbstractSingle-phase polycrystalline PbZrO3 (PZ) thin films, 3000-6000 A thick, have been grown by metal-organic chemical vapor deposition (MOCVD) on (111)Pt/Ti/SiO2/Si substrates at ≍525°C. X-ray diffraction analysis indicated that the PZ films grown on (111)Pt/Ti/SiO2/Si (Pt/Tgi/Si) showed preferred pseudocubic (110) orientation. In contrast, PZ films grown on 150 A thick PbTiO3 (PT) template layers exhibited a pseudocubic (100) preferred orientation, and PZ films deposited on TiO2 template layers consisted of randomly oriented grains. The PZ films grown on Pt/Ti/Si with or without templates exhibited dielectric constants of 120-200 and loss tangents of 0.01-0.0. The PZ films with (110) orientation exhibited an electric-field-inducedtransformation from the antiferroelectric phase to the ferroelectric phase with a polarization of ≍34 µC/cm2, and the energy that was stored during switching was 7.1 J/cm3. The field needed to excite the ferroelectric state and that needed to revert to the antiferroelectric state were 50 and 250 kV/cm, respectively. Relationships between the MOCVD processing and the film microstructure and properties are discussed.


2013 ◽  
Vol 446-447 ◽  
pp. 306-311 ◽  
Author(s):  
Sudhanshu Dwivedi ◽  
Somnath Biswas

Mixed phase TiO2 thin films of rutile and anatase type crystal orientations were deposited on Si substrates by pulsed laser deposition (PLD) technique. When annealed at 800°C at 1 mbar oxygen pressure for 3 h, the deposited films transform into a single phase of rutile type. Structural and morphological studies of the as-deposited and annealed films were performed with X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), Raman spectroscopy, and atomic force microscopy (AFM). Photoluminescence (PL) spectroscopy was used for optical characterization of the annealed thin films.


2009 ◽  
Vol 1199 ◽  
Author(s):  
Danilo G Barrionuevo ◽  
Surinder P Singh ◽  
Maharaj S. Tomar

AbstractWe synthesized BiFe1-xMnxO3 (BFMO) for various compositions by sol gel process and thin films were deposited by spin coating on platinum Pt/Ti/SiO2/Si substrates. X-ray diffraction shows all the diffraction planes corresponding to rhombohedrally distorted perovskite BiFeO3 structure. The absence of any impurity phase in the films suggests the incorporation Mn ion preferentially to Fe site in the structure for low concentration. Magnetic measurements reveal the formation of ferromagnetic phase at room temperature with increased Mn substitution. On the other hand, ferroelectric polarization decreases with increasing Mn ion concentration. Raman studies suggest the dopant induced structural distortion.


Sign in / Sign up

Export Citation Format

Share Document