scholarly journals Ferroelectric Instability and Dimensionality in Bi-Layered Perovskites and Thin Films

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Akira Onodera ◽  
Masanori Fukunaga ◽  
Masaki Takesada
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Properties ◽  
Lattice Strain ◽  
Ferroelectric Phase ◽  
Ferroelectric Film ◽  
Dimensional Structure ◽  
Layered Perovskite ◽  
Thin Ferroelectric Film ◽  
Layered Perovskites

The dielectric and thermal properties of Bi (bismuth)-layered perovskite SrBi2Ta2O9(SBT) are discussed in comparison with ferroelectric thin BaTiO3films. Although these two perovskites exhibit quite a different nature, the dielectric properties of BaTiO3thin film are similar to those in bulk SBT. The dielectric properties and pseudo-two-dimensional structure between SBT and thin film suggest that the bulk layered ferroelectric SBT is a good model of ultra-thin ferroelectric film with two perovskite layers, free from any misfit lattice strain with substrate and surface charge at the interface with electrodes. Based on the mechanism of ferroelectric phase transition of SBT, it seems plausible that the ferroelectric interaction is still prominent but shows a crossover from ferroelectric to antiferroelectric interaction in perovskite ultra-thin films along the tetragonal axis.

The Dielectric Properties of Pb0.65Ba0.35ZrO3 Thin Films

2006 ◽  
Vol 306-308 ◽  
pp. 1313-1318
Author(s):  
J.S. Kim ◽  
B.H. Park ◽  
T.J. Choi ◽  
Se Hyun Shin ◽  
Jae Chul Lee ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Deposition Temperature ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Axis Orientation ◽  
Capacitance Voltage ◽  
Bst Thin Film

Pb0.65Ba0.35ZrO3 (PBZ) thin films have been grown on MgO (001) substrates by pulsed-laser deposition (PLD). We have compared the structural and dielectric properties of PBZ films grown at various temperatures. A highly c-axis orientation has appeared at PBZ film grown at the deposition temperature of 550oC. The c-axis oriented PBZ film has also shown the largest tunability among all the PBZ films in capacitance-voltage measurements. The tunability and dielectric loss of the PBZ film was 20% and 0.00959, respectively. In addition, we have compared the temperature coefficient of capacitance (TCC) of a PBZ film with that of a Ba0.5Sr0.5TiO3 (BST) film which is a well-known material applicable to tunable microwave devices. We have confirmed that TCC value of a PBZ thin film was three-times smaller than that of a BST thin film.

Structure and Dielectric Properties of Mg, Cr-Doped LaSrFeO3 Films

2014 ◽  
Vol 538 ◽  
pp. 11-14
Author(s):  
Yang Lu Hou ◽  
Xing Hua Fu ◽  
Wen Hong Tao ◽  
Xin Jin
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Grain Size ◽  
Dielectric Properties ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Doping Amount ◽  
Single Perovskite Phase ◽  
Pure Perovskite Phase ◽  
Mg Doped

Mg-doped LaFeO3 thin film and Mg, Cr-doped La0.5Sr0.5FeO3 thin films were prepared by the sol-gel method. The change rules of structure and dielectric properties of the films were studied by XRD, SEM, and Agilent. The dielectric properties of La0.5Sr0.5FeO3 and LaFeO3 films were improved by the substitute with Mg and Cr. The doping amount of Mg and Cr for the optimal dielectric properties of La0.5Sr0.5FeO3 films is 45mol%, 25mol%, respectively, and for LaFeO3, the doping amount of Mg is 8mol%. The observed pure perovskite phase of the doped films suggested the dissolution of Mn, Co, and Ni in La0.5Sr0.5FeO3 crystal lattice. Mg and Cr were integrate in the lattice of LaFeO3 and La0.5Sr0.5FeO3, and mineral is single perovskite phase. The surface of the film is smooth, without cracks, surface grain size distribution and had uniform grain size.

Effect of Annealing Temperature on The Refrective Index and Dielectric Properties of TiO2/MnO2 CORE/SHELL Thin Films

2014 ◽  
Vol 6 (3) ◽  
pp. 1227-1232
Author(s):  
Peter Ekuma Agbo
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Refractive Index ◽  
Dielectric Properties ◽  
Dielectric Property ◽  
Annealing Temperature ◽  
Xrd Analysis ◽  
Core Shell ◽  
Structural Nature ◽  
Deposited Film

Thin film of the form TiO2/MnO2 was deposited using the chemical bath method. The deposited thin films were annealed at temperatures of in order to investigate the effect of annealing temperature on the refractive index and dielectric property. To do this the films were characterized using UV-Spectrophotometer and XRD analysis was also carriedout to study the structural nature of the deposited film. Our results reaveled that annealing has profound effect on theindex of refraction and the dielectric properties.  

A High Throughput Search of Dielectric Thin Films for Tunable Devices

2006 ◽  
Vol 45 ◽  
pp. 2351-2354
Author(s):  
Ji Won Choi ◽  
Chong Yun Kang ◽  
Jin Sang Kim ◽  
Seok Jin Yoon ◽  
Hyun Jai Kim ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Rf Magnetron Sputtering ◽  
Dielectric Materials ◽  
Si Substrate ◽  
Dielectric Thin Films ◽  
Low Dielectric ◽  
Film Dielectric

The dielectric properties of (Ba,Sr)TiO3 (BSTO) and Zr doped BSTO thin films have been investigated to identify candidate thin film dielectric materials having low dielectric loss without degradation of the tunability by continuous composition spread (CCS) technique using off-axis rf magnetron sputtering. The optimized properties of BSTO thin films deposited on Pt/SiO2/Si substrate by CCS were dielectric loss 0.031, tunability 31.5, respectively. The optimized properties of Zr doped BSTO thin films deposited on Pt/SiO2/Si substrate by CCS were improved by dielectric loss 42%, FOM 68% at the same BSTO composition, respectively. To confirm the dielectric properties and compositions by CCS technique, Zr doped BSTO bulk ceramics were evaluated.

SrTiO3 and (Ba,Sr)TiO3 Thin Films Preparation by Ion Beam Sputtering and Their Dielectric Properties

1991 ◽  
Vol 243 ◽  
Author(s):  
Shintaro Yamamichi ◽  
Toshiyuki Sakuma ◽  
Takashi Hase ◽  
Yoichi Miyasaka
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Current Density ◽  
Ion Beam ◽  
Ion Beam Sputtering ◽  
Sapphire Substrates ◽  
Capacitance Voltage ◽  
Beam Sputtering

AbstractSrTiO3 and (Ba,Sr)TiO3 thin films have been prepared by ion beam sputtering on Pd coated sapphire substrates. Film compositions were almost the same as target compositions when powder targets were used. Capacitance-voltage characteristics depended on Sr/Ti ratio of the SrTiO3 films. Only small changes of capacitance value were observed in the range from -3V to 3V when the Sr/Ti ratio was 1.0. Compared with rf-magnetron sputtered film, ion beam sputtered SrTiO3 film indicated lower leakage current density in 50nm thickness. In (Bax,Sr1-x)TiO3 thin films, dielectric constant changed with Ba content (x) and showed a maximum at x=0.5. It also changed with the firing temperature of target powder. The highest value was obtained by using the target powder fired at 900°C. A 100nm thick (Ba0.5,Sr0.5)TiO3 thin film indicated a dielectric constant value of 320.

Radio Frequency (RF) Magnetron Sputtered Barium Strontium Titanate (BST) Thin Film

2017 ◽  
Vol 727 ◽  
pp. 942-946 ◽  
Author(s):  
Juan Li ◽  
Cong Chun Zhang ◽  
Yan Lei Wang ◽  
Yang Gao ◽  
Xiao Lin Zhao
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Properties ◽  
Strontium Titanate ◽  
Barium Strontium Titanate ◽  
Perovskite Phase ◽  
Rf Magnetron Sputtering ◽  
Barium Strontium ◽  
Metal Insulator Metal ◽  
Bst Thin Film

Barium strontium titanate (BST) thin films with excellent dielectric properties are deposited by on-axis RF magnetron sputtering system. The effects of composition of the target and oxygen partial pressure on the microstructure of BST thin film have been investigated. The dielectric properties of the thin films are investigated. The results show that composition of BST thin film deposited with pure argon ambient by the target with 30atm% excess of Ba and Sr is stoichiometric. Perovskite phase can be observed in the thin film annealed in oxygen at 750 °C for 30 min. A metal-insulator-metal (MIM) capacitor is fabricated by microfabrication technique. The capacitance value at 2 GHz is 0.417 pF and 1.42 pF for 50 nm and 90 nm BST thin film respectively, and the leakage current density is 6×10-6 A/cm2 and 5.35×10-8 A/cm2 respectively.

Surface Morphologies of PVDF-TrFE/MgO Nanocomposite Thin Films and its Effect on the Ferroelectric Properties

2015 ◽  
Vol 1134 ◽  
pp. 6-11 ◽  
Author(s):  
Mohamad Hafiz Mohd Wahid ◽  
Rozana Mohd Dahan ◽  
Siti Zaleha Sa'ad ◽  
Adillah Nurashikin Arshad ◽  
Muhamad Naiman Sarip ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Magnesium Oxide ◽  
Ferroelectric Properties ◽  
Filler Loading ◽  
Nanocomposite Thin Film ◽  
Nanocomposite Thin Films ◽  
Surface Morphologies

The enhancement of ferroelectric and dielectric properties of PVDF-TrFE by incorporating various percentages of Magnesium Oxide (1 – 7%) for spin coated nanocomposite thin film was demonstrated. Observations showed uniform distribution and low agglomeration of MgO in the PVDF-TrFE nanocomposite thin film, especially for 3% MgO. Additionally, the 3% MgO incorporated into PVDF-TrFE had generated the highest Pr (88 mC/m2) and dielectric constant (13.6) in comparison other percentage compositions. However, the addition of more than 3% MgO filler loading caused a reduction in the ferroelectric and dielectric properties of the nanocomposite thin films.

scholarly journals Effect of Annealing Process on the Dielectric and Tunable Properties of (Bi1.5Zn0.5)(Nb0.5Ti1.5)O7(BZNT) Thin Film

2021 ◽  
Vol 2133 (1) ◽  
pp. 012009
Author(s):  
Yijian Ma ◽  
Shuang Hou ◽  
Linfeng Lv ◽  
Jiatian Zhang
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Initial Temperature ◽  
Film Formation ◽  
Rf Magnetron Sputtering ◽  
Annealing Process ◽  
Si Substrates ◽  
Structure Surface

Abstract Bi1.5Zn0.5Nb0.5Ti1.5O7 (BZNT) thin films were deposited on Pt/Ti/SiO2/Si substrates by radio frequency (rf) magnetron sputtering. In this paper, by studying the phase structure, surface morphology, and dielectric properties of BZNT films, it is found that by increasing the initial temperature in the annealing process, the film formation quality, internal stress and dielectric properties of the film can be improved. and the best performance of the BZNT film is obtained under the annealing process at the initial temperature of 500°C. The tuning amount (Tu), Dielectric loss (Loss) and quality factor (FOM) are: 13.55 percent, 0.00298 and 45.46, respectively.

Effect of a Boron Additive on the Microstructure and Dielectric Properties of BaTiO3 Thin Films Formed by Nanocrystal Deposition

2013 ◽  
Vol 566 ◽  
pp. 277-280
Author(s):  
Yoko Takezawa ◽  
Minoru Ryu ◽  
Yoshiki Iwazaki ◽  
Toshimasa Suzuki ◽  
Youichi Mizuno ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Low Temperature ◽  
Grain Growth ◽  
Particle Sizes ◽  
Sintering Process ◽  
Mn Doped

Highly crystallized BaTiO3 thin films were fabricated by a nanocrystal sintering process. Boron alkoxide was introduced into a slurry of Mn-doped BaTiO3 nanocrystals with particle sizes of 5-7 nm. The deposited nanocrystal film on a (111)-oriented Pt/TiO2/Al2O3 substrate was sintered at a low temperature of 800 °C and the obtained film had highly densified and oriented microstructures. We found that the boron additive enhanced the grain growth of nanoparticles and as a result the dielectric constant of the thin film increased to 1100 at 10 kHz, which is much higher than that of undoped BaTiO3 thin films.

Sign in / Sign up

Export Citation Format

Share Document