Microstructural and Dielectric Properties of Conventional and Microwave Sintered CaCu3Ti4O12 Ceramics

2012 ◽  
Vol 727-728 ◽  
pp. 1063-1068 ◽  
Author(s):  
Daniel Thomazini ◽  
Maria Virginia Gelfuso ◽  
Gabriel Moreira Lima ◽  
José Antônio Eiras
Keyword(s):  
Dielectric Properties ◽  
Sintering Temperature ◽  
Hold Time ◽  
Microwave Oven ◽  
Dielectric Constants ◽  
Chemical Route ◽  
Microelectronic Devices ◽  
Sintering Conditions ◽  
Strong Candidate ◽  
High Dielectric

ts well known that CaCu3Ti4O12(CCTO) ceramic presents high dielectric constants, which makes it a strong candidate to be used in microelectronic devices. Several routes were proposed to obtain CCTO crystalline phase, influencing in microstructure and sintering conditions of the ceramics. In this study CCTO powders were produced by a new chemical route, providing reduction on hold time and sintering temperature. Furthermore, the sintering was performed in conventional and microwave oven that produced different microstructures. In this way, the microstructure and dielectric properties of these ceramics were evaluated and compared, showing the higher values of dielectric constant due to lower grain size and reduced copper-rich phase on grain boundary presented by microwave sintered ceramics.

HIGH DIELECTRIC PROPERTIES OF LOW-TEMPERATURE SINTERED (Ca0.5Cu0.5)TiO3 CERAMICS

2011 ◽  
Vol 01 (02) ◽  
pp. 203-207 ◽  
Author(s):  
JIAN-CONG YUAN ◽  
YUAN-HUA LIN ◽  
BO CHENG ◽  
CE-WEN NAN
Keyword(s):  
Dielectric Properties ◽  
Sintering Temperature ◽  
Sol Gel ◽  
Impedance Spectrum ◽  
Dielectric Constants ◽  
Sintering Process ◽  
Remarkable Effect ◽  
High Dielectric Permittivity ◽  
Wide Range ◽  
High Dielectric

High dielectric-permittivity ( Ca0.5Cu0.5)TiO3 -based ceramics have been prepared by a sol-gel method combined with a solid state sintering process. The results indicate that the additives of H3BO3 have a remarkable effect on the sintering temperature, microstructure and dielectric properties. High density ( Ca0.5Cu0.5)TiO3 bulk ceramics can be obtained after sintering at 900°C. The as-sintered ceramics show high dielectric constants (~1000), and low losses (~0.05). The dielectric properties are nearly independent of frequency and temperature in a wide range. The activation energy is calculated as about 0.50 eV by impedance spectrum method.

The Effects of Sintering Temperature on the Dielectric Properties of Sr(FeNb)0.5O3 Doped with Ba(Zr0.25Ti0.75)O3

2016 ◽  
Vol 675-676 ◽  
pp. 651-654
Author(s):  
Lalita Tawee ◽  
Kachaporn Sanjoom ◽  
Thanatep Phatungthane ◽  
Tawee Tunkasiri ◽  
Gobwute Rujijanagul ◽  
...  
Keyword(s):  
Grain Size ◽  
Dielectric Properties ◽  
Solid State ◽  
Wide Temperature Range ◽  
Solid State Reaction ◽  
Sintering Temperature ◽  
Dielectric Constants ◽  
Solid State Reaction Technique ◽  
Cubic Symmetry ◽  
High Dielectric

In this work, ceramics of Sr(Fe0.5Nb0.5O3) doped with Ba(Zr0.25Ti0.75)O3 (10 mol%), were synthesized by a solid-state reaction technique. The powders were calcined at 1300 °C for 12 hr and then sintered at 1400-1500 °C for 4 hr. Effects of sintering temperature on the properties of the ceramic were studied. Phase formation, microstructure, and dielectric properties were investigated. The ceramics exhibited a perovskite structure with cubic symmetry. Grain size of the ceramics increased with increasing the sintering temperature. The ceramics exhibited a dielectric relaxation like behavior with high dielectric constants over a wide temperature range

Dielectric Properties of Y2NiMnO6 Ceramics at Various Sintering Times and Temperatures

2015 ◽  
Vol 804 ◽  
pp. 16-20 ◽  
Author(s):  
Panakamon Deeyai ◽  
Thanapong Sareein ◽  
Bundit Putasaeng ◽  
Naphat Chathirat
Keyword(s):  
Dielectric Properties ◽  
Dielectric Loss ◽  
Dielectric Permittivity ◽  
Room Temperature ◽  
Sintering Temperature ◽  
Dielectric Constants ◽  
The Other ◽  
Other Hand ◽  
Low Sintering Temperature ◽  
Sintering Conditions

Dielectric properties of hydrothermally decomposed Y2NiMnO6 ceramics prepared under several sintering conditions were investigated at room temperature. As the results, dielectric constants at 200 Hz were found about 928 and 23x103 for samples sintered at 1000 and 1400 oC, respectively. The dielectric permittivity for samples sintered at 1400 oC for different sintering times from 6 to 24 hours have yielded the best dielectric permittivity value of 104. On the other hand, low sintering temperature had resulted in smaller dielectric loss in comparison to larger dielectric loss generally found in the ceramics with high sintering temperature.

New Perovskite Nanomaterials and Their Integrations into High-k Dielectrics

2011 ◽  
Vol 2011 (CICMT) ◽  
pp. 000072-000077
Author(s):  
Minoru Osada ◽  
Takayoshi Sasaki
Keyword(s):  
Dielectric Properties ◽  
Room Temperature ◽  
Bottom Electrode ◽  
Dielectric Constants ◽  
Dielectric Films ◽  
Layered Perovskite ◽  
Layer By Layer ◽  
High K ◽  
High K Dielectric ◽  
High Dielectric

We report on a bottom-up manufacturing for high-k dielectric films using a novel nanomaterial, namely, a perovskite nanosheet (LaNb2O7) derived from a layered perovskite by exfoliation. Solution-based layer-by-layer assembly of perovskite nanosheets is effective for room-temperature fabrication of high-k nanocapacitors, which are directly assembled on a SrRuO3 bottom electrode with an atomically sharp interface. These nanocapacitors exhibit high dielectric constants (k > 50) for thickness down to 5 nm while eliminating problems resulting from the size effect. We also investigate dielectric properties of perovskite nanosheets with different compositions (LaNb2O7, La0.95Eu0.05Nb2O7, and Eu0.56Ta2O7) in order to study the influence of A- and B-site modifications on dielectric properties.

Microstructure and Dielectric Properties of LixTixNi1-2xO Thin Films

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 ◽  
High Dielectric

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.

EFFECTS OF V2O5 ADDITION ON MICROWAVE DIELECTRIC PROPERTIES OF 16CaO-9Li2O-12Sm2O3-63TiO2 CERAMICS

2009 ◽  
Vol 23 (06n07) ◽  
pp. 1021-1027
Author(s):  
YONGJUN GU ◽  
JINLIANG HUANG ◽  
DAOMING SUN ◽  
QIAN LI ◽  
XIAO WANG ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Mixed Oxides ◽  
Sintering Temperature ◽  
Microwave Dielectric Properties ◽  
Dielectric Constants ◽  
Sintering Aid ◽  
Microwave Dielectric

Effects of V 2 O 5 addition on the microwave dielectric properties of 16 CaO -9 Li 2 O -12 Sm 2 O 3-63 TiO 2 (abbreviated CLST) ceramics prepared by conventional mixed oxides method were investigated as a function of V 2 O 5 content and sintering temperature. All the specimens were sintered between 1100°C and 1250°C. The sintering temperature of the CLST ceramics was lowered by 100°C with V 2 O 5 addition. With the changing content of V 2 O 5, the dielectric constants lie between 88.6 and 108.2, while the Q × f values are between 3275 and 6573 GHz. Especially, the specimens doped by 0.75 wt% V 2 O 5 sintered at 1200°C and 1250°C for 3 h show good microwave dielectric properties with Kr =100.4-108.2, Q × f >4500 GHz , and TCF=7-8 ppm/°C. Obviously, V 2 O 5 could be used as a suitable sintering aid that could improve densification and microwave dielectric properties of the CLST ceramics.

Preparation, Morphology and Dielectric Properties of Polyamide-6/Poly(Vinylidene Fluoride) Blends

2012 ◽  
Vol 496 ◽  
pp. 263-267
Author(s):  
Rui Li ◽  
Jian Zhong Pei ◽  
Yan Wei Li ◽  
Xin Shi ◽  
Qun Le Du
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Flexible Electronics ◽  
High Dielectric Constant ◽  
Vinylidene Fluoride ◽  
Volume Fraction ◽  
Polyamide 6 ◽  
Dielectric Constants ◽  
Poly Vinylidene Fluoride ◽  
High Dielectric

A novel all-polymeric material with high dielectric constant (k) has been developed by blending poly (vinylidene fluoride) (PVDF) with polyamide-6 (PA6). The dependence of the dielectric properties on frequency and polymer volume fraction was investigated. When the volume fraction of PA6 is 20%, the dielectric property is better than others. The SEM investigations suggest that the enhanced dielectric behavior originates from significant interfacial interactions of polymer-polymer. The XRD demonstrate that the PA6 and PVDF affect the crystalline behavior of each component. Furthermore, the stable dielectric constants of the blends could be tuned by adjusting the content of the polymers. The created high-k all-polymeric blends represent a novel type of material that are simple technology and easy to process, and is of relatively high dielectric constant, applications as flexible electronics.

Sintering characteristics and microwave dielectric properties of 0.5(Ca0.7Nd0.2)TiO3–0.5(Li0.5Nd0.5)TiO3 ceramics with La2O3–B2O3–CaO–P2O5 additive

2021 ◽  
Author(s):  
Jiawen Shi ◽  
Xingyu Chen ◽  
Weijun Zhang ◽  
Haijun Mao ◽  
Fenglin Wang ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
High Dielectric Constant ◽  
Sintering Temperature ◽  
Glass Ceramics ◽  
Microwave Dielectric Properties ◽  
Low Loss ◽  
Sintering Aid ◽  
Microwave Dielectric ◽  
Sintering Characteristics ◽  
High Dielectric

In this paper, the effects of glass-ceramics sintering aid, La2O3–B2O3–CaO–P2O5 (LBCP), on the sinterability, microstructure, and microwave dielectric properties of 0.5(Ca[Formula: see text]Nd[Formula: see text]TiO3–0.5(Li[Formula: see text]Nd[Formula: see text]TiO3 (CNT–LNT) ceramic have been investigated. The results indicated that LBCP glass-ceramics has good wettability to CNT–LNT (contact angle at 980[Formula: see text]C is 31.9[Formula: see text]), and it can be used as an effective sintering aid to reduce the sintering temperature of CNT–LNT ceramic from 1300[Formula: see text]C to 980[Formula: see text]C. LBCP glass-ceramics did not change the main crystal phase (perovskite structure) of the sample, but a small amount of LaBO3 and LaPO4 phases was precipitated. Since the LaBO3 and LaPO4 phases are low-loss phases, it is believed that the crystal phases can improve the dielectric properties of the sample, especially the dielectric loss. The samples with 10 wt.% of glass additive sintered for 4 h at 980[Formula: see text]C exhibit the optimized properties: a high dielectric constant of 80.8 and a [Formula: see text] value of 2031 GHz. The high [Formula: see text] and [Formula: see text] value, coupled with a relatively low sintering temperature, suggest that the optimized compositions have the potential to be used in microwave low-temperature co-fired ceramics applications.

Effects of CuO-V2O5-Bi2O3 Additions on the Microstructure and Microwave Dielectric Properties of 0.42ZnNb2O6-0.58TiO2 Ceramics

2007 ◽  
Vol 280-283 ◽  
pp. 27-30
Author(s):  
Jin Wang ◽  
Zhen Xing Yue ◽  
Ying Chun Zhang ◽  
Zhi Lun Gui ◽  
Long Tu Li
Keyword(s):  
Dielectric Properties ◽  
Sintering Temperature ◽  
Microwave Dielectric Properties ◽  
Dielectric Constants ◽  
Microwave Dielectric

The effects of additions on the microstructure and microwave dielectric properties of 0.42ZnNb2O6-0.58TiO2 (ZNT) ceramics were investigated systematically. The sintering temperature of ZNT ceramics doped with different amounts of CuO, Bi2O3 and V2O5 can be effectively reduced. The phase of doped samples was studied compared to the undoped ZNT ceramics. For densified ZNT ceramics with the increasing amount of dopant CuO-Bi2O3-V2O5, the dielectric constants (εr) of densified samples ranges from 38 to 42, the Q×f values decrease evidently and ranges from 13300 GHz to 5000 GHz and the τf values are shifted toward negative.

Sintering Temperature Influence on Microwave Dielectric Properties of TiO2-ZrO2 Ceramics

2010 ◽  
Vol 660-661 ◽  
pp. 646-651
Author(s):  
José Vitor C. Souza ◽  
Pedro José Castro ◽  
Maria do Carmo de Andrade Nono ◽  
Sergio Luiz Mineiro
Keyword(s):  
Dielectric Properties ◽  
Sintering Temperature ◽  
Microwave Dielectric Properties ◽  
Dielectric Constants ◽  
Dielectric Resonators ◽  
Temperature Influence ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Dielectric ◽  
Dielectric Ceramics

Dielectric ceramics have been widely investigated and used for microwave applications such as resonators and filters. The present study deals with the influence of sintering temperature on microwave dielectric properties of TiO2 ceramics with 10, 20, and 30 wt% ZrO2. Three compositions have been developed through mixing procedures and then tested for each sintering temperature: 1500 and 1400 °C. X-ray diffraction and scanning electron microscopy are carried out aiming to explain the ceramic behavior of each sample. The dielectric constants of different ceramics for both temperatures varied from 85.4 to 62.6, while their quality factor due to dielectric losses varied from 3110 to 1630. The Q decrease is attributed to the non uniform grain growth and to the obtained crystalline phases. The best microwave parameters were obtained for the ceramics sintered at 1400 °C, which can be applied in microwave circuits as dielectric resonators.

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