Dielectric Properties of BST/(Y2O3)x(ZrO2)1-x/BST Trilayer Films

ABSTRACTThin films of Ba1-xSrxTiO3 (BST) are being actively investigated for applications in dynamic random access memories (DRAM) because of their properties such as high dielectric constant, low leakage current, and high dielectric breakdown strength. Various approaches have been used to improve the dielectric properties of BST thin films such as doping, graded compositions, and multilayer structures. We have found that inserting a ZrO2 layer in between two BST layers results in a significant reduction in dielectric constant as well as dielectric loss. In this work the effect of Y2O3 doped ZrO2 on the dielectric properties of BST/ZrO2/BST trilayer structure is studied. The structure Ba0.8Sr0.2TiO3/(Y2O3)x(ZrO2)1-x/Ba0.8Sr0.2TiO3 is deposited by a sol-gel process on platinized Si substrate. The composition (x) of the middle layer is varied while keeping the total thickness of the trilayer film constant. The dielectric constant of the multilayer film decreases with the increase of Y2O3 amount in the film whereas there is a slight variation in dielectric loss. In Y2O3 doped multilayer thin films, the dielectric loss is lower in comparison to other films and also there is good frequency stability in the loss in the measured frequency range and hence very suitable for microwave device applications.

Effect of the Difference in Dielectric Constant of the Phases on Dielectric Property of the Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.814.137 ◽

2015 ◽

Vol 814 ◽

pp. 137-143

Author(s):

Hao Zhou ◽

Qing Meng Zhang ◽

Qun Tang ◽

Hang Cui ◽

Yao Hua Xu ◽

...

Keyword(s):

Dielectric Constant ◽

Dielectric Properties ◽

Dielectric Breakdown ◽

Breakdown Strength ◽

Ferroelectric Properties ◽

Relative Dielectric Constant ◽

Practical Application ◽

The Difference ◽

The composites have a great use in practical application. In common, the phases in composite have different relative dielectric constant and in order to reveal how the phases with different permittivity affect the composite’s dielectric properties, the experiments were carried out using inorganic and organic composite with different dielectric constant phases to make that clear. The barium niobate-based SiO2system glass–ceramic and fillers-epoxy resin composites were chosen, and the dielectric properties were tested to compare the difference of those composites. The results show that the existence of high dielectric constant phases in composites can improve the permittivity of composites and make the composites present ferroelectric properties, while the dielectric loss can also increased, and the difference in dielectric constant of the phases can decrease the dielectric breakdown strength.

Microstructure and Microwave Dielectric Properties of BaTi4O9 Ceramics Derived from a Sol-Gel Precursor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.326.127 ◽

2011 ◽

Vol 326 ◽

pp. 127-130

Author(s):

Xian Li Huang ◽

Fu Ping Wang ◽

Ying Song

Keyword(s):

Dielectric Constant ◽

Dielectric Properties ◽

Dielectric Loss ◽

Sol Gel ◽

Microwave Dielectric Properties ◽

Sintering Process ◽

Temperature Coefficients ◽

Microwave Dielectric ◽

Ceramic Samples ◽

Quality Factor Q

In the present work, the microstructure and microwave dielectric properties of BaTi4O9 ceramics derived from a sol-gel precursor were presented. Density measuring results demonstrated that the largest densities of ceramic sample about 96.7% could be reached by virtue of a cool iso-static press and a sintering process at at 1300 °C for 6 hours. The dielectric constant (εr), quality factor (Q×f) and the temperature coefficients (τf) of the BaTi4O9 ceramic samples were 36.65, 28000 GHz, +20.2 ppm/°C, respectively. XRD, SEM and XPS were used to characterize the microstructure of the ceramics samples. Substantial Ti3+ was proposed to be the cause of dielectric loss.

Microstructure and Dielectric Properties of LixTixNi1-2xO Thin Films

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1817 ◽

2008 ◽

Vol 368-372 ◽

pp. 1817-1819

Author(s):

Cui Hua Zhao ◽

Bo Ping Zhang ◽

Yong Liu ◽

Song Jie Li

Keyword(s):

Thin Films ◽

Dielectric Properties ◽

Spin Coating ◽

Sol Gel ◽

Dielectric Constants ◽

Co Doping ◽

Grain Sizes ◽

Uniform Microstructure ◽

Coating Method ◽

LixTixNi1-2xO (x =0, 10 and 20 at. %) thin films with 200 nm in thickness were deposited on Pt/Ti/SiO2/Si (100) by a sol-gel spin-coating method. All samples have a uniform microstructure. The grain sizes grew from 100 nm to 300 nm by co-doping Li and Ti. The LiTiNiO thin films consist of NiO, NiTiO3 and Li2NiO2, while the Li-free thin films consist of NiO, NiTiO3 and NiTi0.99O3. The dielectric properties of the LiTiNiO thin films improved obviously by co-doping Li and Ti, but excess Li increases the amount of Li2NiO2 phase and decreases the dielectric properties. The dielectric constants at 100 Hz for the Li0.1Ti0.1Ni0.8O and Li0.2Ti0.2Ni0.6O thin films are 506 and 388 respectively. Appropriate co-doping contents of Li and Ti are important to obtain a high dielectric property.

Crystallization and Dielectric Properties of MWCNT /Poly(1-Butene) Composite Films by a Solution Casting Method

Materials ◽

10.3390/ma13030755 ◽

2020 ◽

Vol 13 (3) ◽

pp. 755

Author(s):

Lingfei Li ◽

Qiu Sun ◽

Xiangqun Chen ◽

Yongjun Xu ◽

Zhaohua Jiang

Keyword(s):

Dielectric Constant ◽

Dielectric Properties ◽

Dielectric Loss ◽

Breakdown Strength ◽

Composite Films ◽

Conductive Filler ◽

Interfacial Polarization ◽

Solution Casting ◽

Casting Method ◽

Solution Casting Method

In this work, poly(1-butene) (PB-1) composite films with multi-walled carbon nanotubes (MWCNT) were prepared by a solution casting method. The relationship between the dielectric properties and the crystal transformation process of the films was investigated. It was indicated that there were two crystal forms of I and II of PB-1 during the solution crystallization process. With the prolongation of the phase transition time, form II was converted into form I. The addition of the conductive filler (MWCNT) accelerated the rate of phase transformation and changed the nucleation mode of PB-1. The presence of crystal form I in the system increased the breakdown strength and the dielectric constant of the films and reduced the dielectric loss, with better stability. In addition, the dielectric constant and the dielectric loss of the MWCNT/PB-1 composite films increased with the addition of MWCNT, due to the interfacial polarization between MWCNT and PB-1 matrix. When the mass fraction of the MWCNT was 1.0%, the composite film had a dielectric constant of 43.9 at 25 °C and 103 Hz, which was 20 times that of the original film.

Effect of Thermal Stress on the Microwave Dielectric Properties of (300-X) nm MgTiO3 /(X) nm CaTiO3 Thin Films

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.2332 ◽

2006 ◽

Vol 45 ◽

pp. 2332-2336

Author(s):

Ki Hyun Yoon ◽

Ji Won Choi

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Thermal Expansion ◽

Thermal Stress ◽

Dielectric Properties ◽

Dielectric Loss ◽

Microwave Dielectric Properties ◽

Mixing Rule ◽

Microwave Dielectric ◽

Dielectric Layers

The microwave dielectric properties of (300-X) nm MgTiO3/(X) nm CaTiO3 thin films have been investigated with correlation between the interface and stress induced by dielectric layers with heattreatment. As the thickness (X) of CaTiO3 film increased, the dielectric constant increased and the temperature coefficient of the dielectric constant changed from the positive to the negative values by the dielectric mixing rule. The dielectric loss of (300-X) nm MgTiO3/(X) nm CaTiO3 thin films increased with an increase of the thickness (X) of CaTiO3 film because of higher thermal stress induced by the higher thermal expansion coefficient of CaTiO3 than that of MgTiO3.

Fabrication of barium titanate thin films with a high dielectric constant by a sol–gel technique

Thin Solid Films ◽

10.1016/s0040-6090(99)00427-7 ◽

1999 ◽

Vol 353 (1-2) ◽

pp. 144-148 ◽

Cited By ~ 44

Author(s):

Hidehiro Kumazawa ◽

Kazuaki Masuda

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Barium Titanate ◽

Sol Gel ◽

Gel Technique ◽

Dielectric Properties of Li-Doped CaCu3Ti4O12 Ceramics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.687.251 ◽

2011 ◽

Vol 687 ◽

pp. 251-256 ◽

Cited By ~ 1

Author(s):

Ying He ◽

Huai Wu Zhang ◽

Yuan Xun Li ◽

Wei Wei Ling ◽

Yun Yan Wang ◽

...

Keyword(s):

Dielectric Constant ◽

Dielectric Properties ◽

Dielectric Loss ◽

Secondary Phase ◽

Doping Amount ◽

Spectroscopy Analysis ◽

Low Dielectric ◽

Tan Δ ◽

High Dielectric ◽

Impedance Spectroscopy Analysis

CaCu3Ti4O12 ceramics doped with 0-2.0 wt% Li2CO3 were prepared by the solid-state reaction, and their electric and dielectric properties were investigated. It is found that these ceramics had the properties of high dielectric constant and comparatively low dielectric loss. At the doping amount of 0.5 wt%, the dielectric constant is kept to be 105 with weak frequency dependence below 105 Hz, and its loss tangent (tan δ) is suppressed below 0.1 between 300 Hz-5 kHz (with the minimum value of 0.06 at 1 kHz from 218 K to 338 K). The impedance spectroscopy analysis confirms that the decrease of dielectric loss is mainly due to the increase of resistance in the grain boundary, which may be related to the influence of Ti4O7 secondary phase. Our result indicates that doping Li2CO3 is an efficient method to optimize the dielectric properties of CaCu3Ti4O12.

Characterization of Sol-Gel-Derived and Crystallized HfO2, ZrO2, ZrO2-Y2O3 Thin Films on Si(001) Wafers with High Dielectric Constant

Advances in Crystallization Processes ◽

10.5772/35727 ◽

2012 ◽

Cited By ~ 1

Author(s):

Hirofumi Shimizu ◽

Toshikazu Nishide

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Sol Gel ◽

High-Dielectric-Constant PLZT Films on Metal Foils for Embedded Passives

International Symposium on Microelectronics ◽

10.4071/isom-2010-wa5-paper4 ◽

2010 ◽

Vol 2010 (1) ◽

pp. 000521-000527

Author(s):

Beihai Ma ◽

Manoj Narayanan ◽

U. (Balu) Balachandran

Keyword(s):

Dielectric Constant ◽

Dielectric Loss ◽

Electric Fields ◽

Breakdown Strength ◽

Time To Failure ◽

Lead Lanthanum Zirconate Titanate ◽

Metal Foils ◽

Accelerated Lifetime ◽

Ceramic film capacitors with high dielectric constant and high breakdown strength would result in advanced power electronic devices with higher performance, improved reliability, and enhanced volumetric and gravimetric efficiencies. We have grown ferroelectric films of lead lanthanum zirconate titanate (PLZT) on base metal foils by chemical solution deposition. Their dielectric properties were characterized over the temperature range between −50 and 150°C. We measured a dielectric constant of ≈700 and dielectric loss of ≈0.07 at −50°C and a dielectric constant of ≈2200 and dielectric loss of ≈0.06 at 150°C. At room temperature, we measured a leakage current density of ≈6.6 × 10−9 A/cm2, mean breakdown strength of 2.6 MV/cm, and energy density >85 J/cm3. A series of highly accelerated lifetime tests (HALT) was performed to determine the reliability of these PLZT film-on-foil capacitors under high temperature and high field stress conditions. Samples were exposed to temperatures ranging from 100 to 150°C and electric fields ranging from 8.7 × 105 V/cm to 1.3 × 106 V/cm during the HALT testing. Breakdown behavior of the samples was evaluated by Weibull analysis. The mean time to failure was projected to be >3000 h at 100°C with a dc electric field of ≈2.6 × 105 V/cm.