EFFECT OF Ce-DOPING ON STRUCTURAL AND ELECTRICAL PROPERTIES OF DIELECTRIC Bi2Ti2O7 THIN FILMS

2008 ◽  
Vol 15 (06) ◽  
pp. 799-803 ◽  
Author(s):  
XIANGYANG JING ◽  
BAIBIAO HUANG ◽  
SHUSHAN YAO ◽  
QI ZHANG ◽  
ZEYAN WANG ◽  
...  

Ce -doped Bi 2 Ti 2 O 7 thin films have been successfully prepared on P-type Si substrates by a chemical solution deposition method. The structural properties of the films were studied by X-ray diffraction. The phase of Ce -doped Bi 2 Ti 2 O 7 was more stable than that of Bi 2 Ti 2 O 7 without Ce substitution. The films exhibited good insulating properties at room temperature. The dielectric constant of the films annealed at 700°C at 100 kHz was 168 and the dissipation factor was 0.038. All these results showed that Ce -doped Bi 2 Ti 2 O 7 thin films could be used as storage capacitors in DRAM and MOS.

2006 ◽  
Vol 320 ◽  
pp. 49-52
Author(s):  
Hiroshi Uchida ◽  
Hiroshi Nakaki ◽  
Hiroshi Funakubo ◽  
Seiichiro Koda

The electrical properties of perovskite-based ferroelectric films were improved by ion modification using rare-earth cations. Thin films of rare-earth-modified lead zirconate titanate [Pb(Zr,Ti)O3] were fabricated on (111)Pt/Ti/SiO2/(100)Si substrates by a chemical solution deposition technique. The substitution of volatile cations in the simple-perovskite oxides, such as Pb2+ in Pb(Zr,Ti)O3 films, enhanced the insulating properties of the film. The crystal anisotropy of the Pb(Zr,Ti)O3 film could be controlled by varying the species and the amount of replacing cations to enhance the spontaneous polarization. Thus, ion modification using Dy3+ cation could enhance the remanent polarization of Pb(Zr,Ti)O3 film consequently.


2002 ◽  
Vol 748 ◽  
Author(s):  
Dinghua Bao ◽  
Naoki Wakiya ◽  
Kazuo Shinozaki ◽  
Nobuyasu Mizutani

ABSTRACT(Bi,La)4Ti3O12 (BLT) thin films with various Bi2O3 template layers were prepared on Pt/Ti/SiO2/Si substrates by a chemical solution deposition method. Both of the BLT films with a thin Bi2O3 template layer and those without a Bi2O3 layer had a highly c-axis oriented growth, while both of the BLT films with a thin Bi2O3 bottom layer and those with a Bi2O3 intermediate layer were highly c-axis oriented. It was found that the use of Bi2O3 template layers improved significantly the ferroelectric properties of BLT thin films. In addition, the thin films with a thin Bi2O3 template layer showed good dielectric properties. All the capacitors with Bi2O3 template layers showed high polarization fatigue resistance and good retention properties.


2011 ◽  
Vol 8 (1) ◽  
pp. 134-140
Author(s):  
Baghdad Science Journal

The paper reports the influence of annealing temperature under vacuum for one hour on the some structural and electrical properties of p-type CdTe thin films were grown at room temperature under high vacuum by using thermal evaporation technique with a mean thickness about 600nm. X-ray diffraction analysis confirms the formation of CdTe cubic phase at all annealing temperature. From investigated the electrical properties of CdTe thin films, the electrical conductivity, the majority carrier concentration, and the Hall mobility were found increase with increasing annealing temperatures.


1999 ◽  
Vol 596 ◽  
Author(s):  
E. Ching-Prado ◽  
W. Pérez ◽  
P. S. Dobalt ◽  
R. S. Katiyart ◽  
S. Tirumala ◽  
...  

AbstractThin films of ferroelectric (SrBi2Ta2O9)x(Bi3TiNbO9)1-x layered structure (for x = 0.0, 0.2, … 1.0) were prepared by a metal organic solution deposition method on Pt/TiO2/SiO2/Si substrates. Raman spectroscopy, X-ray diffraction, atomic force microscopy (AFM), and electrical characterization techniques were utilized to study the inclusion of SrBi2Ta2O9 (SBT) in the Bi3TiNbO9 (BTN) system. The Raman spectra show frequency shifts and broadening of modes as x increases from 0.0 to 0.4, which are related to the nature of Sr and Bi in the A-sites, and Ta, Ti, and Nb in the B-sites. Smooth surfaces without any cracks or defects were evidenced in each of these films by AFM. These images also indicate that the grain size in the films increases with increasing SBT content in the BTN compound. Electrical measurements show that the remanent polarization (Pr) and the coercive field (Ec) values in the x=0.0 film (2 μC/cm2 and 30 kV/cm, respectively) increase to 12.5 μC/cm2 and 125 kV/cm for x=0.6. A decrease in these parameters was found for higher compositions.


2015 ◽  
Vol 1731 ◽  
Author(s):  
Luis A. González ◽  
Sara E. Ramírez ◽  
Martín I. Pech-Canul

ABSTRACTHere, we show results on the deposition of ZnO:Al thin films by the successive ionic layer adsorption and reaction method. The growing of the films was performed by sequentially immersing glass and SiO2/Si substrates in water at temperatures close to the boiling point, a precursor reaction solution, water at room temperature and ultrasonic water bath. The resulting ZnO:Al films were transparent and well adhered to the substrates. From X-ray diffraction analysis was determined that the ZnO:Al films had hexagonal wurtzite structure with preferential orientation along the c-axis. Changes in the morphology of the films were obtained from ellipsoidal-shaped aggregates for the undoped ZnO films to spherical-shaped aggregates for the ZnO:Al films. The optical transparency and bandgap of the ZnO:Al films was about 85% and 3.28 eV, respectively. Thin film transistors were fabricated with ZnO:Al films as active layers. The characterized device had a saturation mobility of 0.048 cm2/V-s, threshold voltage of approximately 16.1 V and a drain current on-to-off ratio (Ion/Ioff) in the order of 103.


2011 ◽  
Vol 18 (03n04) ◽  
pp. 121-125 ◽  
Author(s):  
Y. L. DING ◽  
X. H. ZHANG ◽  
C. H. YANG ◽  
X. Y. ZHANG ◽  
H. L. YANG

Both ferroelectric Na0.5Bi0.5TiO3 (NBT) and K0.5Bi0.5TiO3 (KBT) are considered as the best known lead-free materials. In this experiment, we prepared NBT and KBT thin films on Pt/TiO2/SiO2/Si substrates by metalorganic solution deposition. The structural properties and surface morphologies were measured using X-ray diffraction and atomic force microscopy. The NBT and KBT films show higher leakage currents due to the oxygen vacancies in the films. The remanent polarization and coercive field of NBT (KBT) thin film are 9 (5.2) μC/cm2 and 50 (25) kV/cm at an applied electric field of 150 kV/cm. The relative dielectric constants of NBT and KBT are 340 and 316 at 1 MHz, respectively.


2014 ◽  
Vol 1633 ◽  
pp. 25-33 ◽  
Author(s):  
D. S. L. Pontes ◽  
F. M Pontes ◽  
Marcelo A. Pereira-da-Silva ◽  
O. M. Berengue ◽  
A. J. Chiquito ◽  
...  

ABSTRACTLaNiO3 thin films were deposited on SrLaAlO4 (100) and SrLaAlO4 (001) single crystal substrates by a chemical solution deposition method and heat-treated in oxygen atmosphere at 700°C in tube oven. Structural, morphological, and electrical properties of the LaNiO3 thin films were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), field emission scanning electron microscopy (FE-SEM), and electrical resistivity as temperature function (Hall measurements). The X-ray diffraction data indicated good crystallinity and a structural preferential orientation. The LaNiO3 thin films have a very flat surface and no droplet was found on their surfaces. Samples of LaNiO3 grown onto (100) and (001) oriented SrLaAlO4 single crystal substrates reveled average grain size by AFM approximately 15-30 and 20-35 nm, respectively. Transport characteristics observed were clearly dependent upon the substrate orientation which exhibited a metal-to-insulator transition. The underlying mechanism is a result of competition between the mobility edge and the Fermi energy through the occupation of electron states which in turn is controlled by the disorder level induced by different growth surfaces.


2002 ◽  
Vol 17 (2) ◽  
pp. 358-366 ◽  
Author(s):  
Yumi H. Ikuhara ◽  
Xiuliang Ma ◽  
Yuji Iwamoto ◽  
Yuichi Ikuhara ◽  
Koichi Kikuta ◽  
...  

Spinel LiMn2O4 thin films have been prepared on MgO(110) and Au/MgO(110) substrates by a chemical solution deposition method. The interfaces between film and substrate were characterized by means of high-resolution transmission electron microscopy (HREM) as well as x-ray diffraction. Cross-sectional HREM observation revealed that LiMn2O4 films grew epitaxially on the MgO(110) and Au/MgO(110) substrates. In the LiMn2O4/MgO system, misfit dislocations formed to accommodate the lattice strain at the LiMn2O4/MgO interface. In the LiMn2O4/Au/MgO system, Au grew epitaxially on the MgO substrate with its surface facetted along {111} planes, probably because the surface energy of this plane is relatively low. The formation of these facets is considered to have a favorable effect on the growth of {111} planes of LiMn2O4 when deposited on the Au film.


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