Processing-Dependent Dielectric and Ferroelectric Properties of BST Ceramics
Нема приказа
Аутори
Ćirković, JovanaVojisavljević, Katarina
Nikolic, Nenad
Tasić, Nikola
Branković, Zorica
Sreckovic, Tatjana
Branković, Goran
Конференцијски прилог (Објављена верзија)
Метаподаци
Приказ свих података о документуАпстракт
Barium strontium titanate, BaxSr1-xTiO3 (BST) ceramics have been extensively used as in a microelectronics due
to its excellent ferroelectric, dielectric, piezoelectric, and pyroelectric properties [1–3]. At room temperature
BST is ferroelectric when x is in the range of 0.7–1, and has a maximum dielectric constant around x = 0.8 [4].
Characteristics of BST powders strongly depend on their synthesis. To achieve the desired properties and
practical application, BST powder needs to be free of intermediate phases, with a defined stoichiometry and
homogenous microstructure.
The commonly used techniques to produce BST powders are conventional solid state processing, complex
polymerization method, and hydrothermal method. The solid state reaction is most common technique for
preparation of BST powders, but it is faced with several disadvantages such as large particle size distribution,
non-homogeneity and presence of impurities, which can negatively affect the properties of BST cera...mics.
Hydrothermal technique is able to produce uniform, nanosized, low agglomerated BST particles at low
temperature, but it is hard to control the stoichiometry of the final products. In this study, BST powder
Ba0.8Sr0.2TiO3 was obtained by hydrothermal treatment of precursor solution containing titanium citrate, barium
and strontium acetates, previously prepared by complex polymerization method. By combining the advantages
of both methods a fine, nanosized BST powder was synthesized with homogeneous particle size distribution [5].
The calcined BST powders were pressed into pellets and sintered at 1280°C with different dwelling times, from
1 to 32 h. The phase compositions of the sintered samples were determined by X-ray diffraction (XRD) and
EDS analysis. Microstructural properties were investigated by scanning electron microscopy. The phase
transitions and dielectric properties were investigated by measuring dielectric permittivity (ε) and dielectric
losses (tanδ) as a function of temperature. Ferroelectric properties such as remanent polarization (Pr) and
coercitive field (Ec) were determinated by polarization-electric field (P-E) measurements.
The main objective of this work was to investigate the changes in the phase composition, structural parameters
and microstructure of BST ceramics and their influence on dielectric and ferroelectric properties. XRD analysis
of BST ceramics showed that crystallite size and phase composition varied with different sintering times. It was
found that the sintering process leads to a formation of secondary phases; Ba6Ti17O40, BaTi2O5 and SrTi21O38 on
Ti-rich side, and Ba2TiO4 on Ba-rich side. The sintered samples underwent an abnormal grain growth, whereby
some grains grew faster than others due to the presence of multi-phase structure. It was found that dielectric and
ferroelectric properties of BST ceramics strongly depended on grain size, density, phase compositions and
defects.
Кључне речи:
barium strontium titanate / nanpowder / dielectric properties / microstructureИзвор:
ECAPD Conference on Application of Polar Dielectrics 2014, Vilnius, Lithuania, 2014, 90-Издавач:
- Vilnius University, Vilnius, Lithuania
Финансирање / пројекти:
- 0-3D наноструктуре за примену у електроници и обновљивим изворима енергије: синтеза, карактеризација и процесирање (RS-MESTD-Integrated and Interdisciplinary Research (IIR or III)-45007)
Институција/група
Institut za multidisciplinarna istraživanjaTY - CONF AU - Ćirković, Jovana AU - Vojisavljević, Katarina AU - Nikolic, Nenad AU - Tasić, Nikola AU - Branković, Zorica AU - Sreckovic, Tatjana AU - Branković, Goran PY - 2014 UR - http://rimsi.imsi.bg.ac.rs/handle/123456789/2925 AB - Barium strontium titanate, BaxSr1-xTiO3 (BST) ceramics have been extensively used as in a microelectronics due to its excellent ferroelectric, dielectric, piezoelectric, and pyroelectric properties [1–3]. At room temperature BST is ferroelectric when x is in the range of 0.7–1, and has a maximum dielectric constant around x = 0.8 [4]. Characteristics of BST powders strongly depend on their synthesis. To achieve the desired properties and practical application, BST powder needs to be free of intermediate phases, with a defined stoichiometry and homogenous microstructure. The commonly used techniques to produce BST powders are conventional solid state processing, complex polymerization method, and hydrothermal method. The solid state reaction is most common technique for preparation of BST powders, but it is faced with several disadvantages such as large particle size distribution, non-homogeneity and presence of impurities, which can negatively affect the properties of BST ceramics. Hydrothermal technique is able to produce uniform, nanosized, low agglomerated BST particles at low temperature, but it is hard to control the stoichiometry of the final products. In this study, BST powder Ba0.8Sr0.2TiO3 was obtained by hydrothermal treatment of precursor solution containing titanium citrate, barium and strontium acetates, previously prepared by complex polymerization method. By combining the advantages of both methods a fine, nanosized BST powder was synthesized with homogeneous particle size distribution [5]. The calcined BST powders were pressed into pellets and sintered at 1280°C with different dwelling times, from 1 to 32 h. The phase compositions of the sintered samples were determined by X-ray diffraction (XRD) and EDS analysis. Microstructural properties were investigated by scanning electron microscopy. The phase transitions and dielectric properties were investigated by measuring dielectric permittivity (ε) and dielectric losses (tanδ) as a function of temperature. Ferroelectric properties such as remanent polarization (Pr) and coercitive field (Ec) were determinated by polarization-electric field (P-E) measurements. The main objective of this work was to investigate the changes in the phase composition, structural parameters and microstructure of BST ceramics and their influence on dielectric and ferroelectric properties. XRD analysis of BST ceramics showed that crystallite size and phase composition varied with different sintering times. It was found that the sintering process leads to a formation of secondary phases; Ba6Ti17O40, BaTi2O5 and SrTi21O38 on Ti-rich side, and Ba2TiO4 on Ba-rich side. The sintered samples underwent an abnormal grain growth, whereby some grains grew faster than others due to the presence of multi-phase structure. It was found that dielectric and ferroelectric properties of BST ceramics strongly depended on grain size, density, phase compositions and defects. PB - Vilnius University, Vilnius, Lithuania C3 - ECAPD Conference on Application of Polar Dielectrics 2014, Vilnius, Lithuania T1 - Processing-Dependent Dielectric and Ferroelectric Properties of BST Ceramics SP - 90 UR - https://hdl.handle.net/21.15107/rcub_rimsi_2925 ER -
@conference{ author = "Ćirković, Jovana and Vojisavljević, Katarina and Nikolic, Nenad and Tasić, Nikola and Branković, Zorica and Sreckovic, Tatjana and Branković, Goran", year = "2014", abstract = "Barium strontium titanate, BaxSr1-xTiO3 (BST) ceramics have been extensively used as in a microelectronics due to its excellent ferroelectric, dielectric, piezoelectric, and pyroelectric properties [1–3]. At room temperature BST is ferroelectric when x is in the range of 0.7–1, and has a maximum dielectric constant around x = 0.8 [4]. Characteristics of BST powders strongly depend on their synthesis. To achieve the desired properties and practical application, BST powder needs to be free of intermediate phases, with a defined stoichiometry and homogenous microstructure. The commonly used techniques to produce BST powders are conventional solid state processing, complex polymerization method, and hydrothermal method. The solid state reaction is most common technique for preparation of BST powders, but it is faced with several disadvantages such as large particle size distribution, non-homogeneity and presence of impurities, which can negatively affect the properties of BST ceramics. Hydrothermal technique is able to produce uniform, nanosized, low agglomerated BST particles at low temperature, but it is hard to control the stoichiometry of the final products. In this study, BST powder Ba0.8Sr0.2TiO3 was obtained by hydrothermal treatment of precursor solution containing titanium citrate, barium and strontium acetates, previously prepared by complex polymerization method. By combining the advantages of both methods a fine, nanosized BST powder was synthesized with homogeneous particle size distribution [5]. The calcined BST powders were pressed into pellets and sintered at 1280°C with different dwelling times, from 1 to 32 h. The phase compositions of the sintered samples were determined by X-ray diffraction (XRD) and EDS analysis. Microstructural properties were investigated by scanning electron microscopy. The phase transitions and dielectric properties were investigated by measuring dielectric permittivity (ε) and dielectric losses (tanδ) as a function of temperature. Ferroelectric properties such as remanent polarization (Pr) and coercitive field (Ec) were determinated by polarization-electric field (P-E) measurements. The main objective of this work was to investigate the changes in the phase composition, structural parameters and microstructure of BST ceramics and their influence on dielectric and ferroelectric properties. XRD analysis of BST ceramics showed that crystallite size and phase composition varied with different sintering times. It was found that the sintering process leads to a formation of secondary phases; Ba6Ti17O40, BaTi2O5 and SrTi21O38 on Ti-rich side, and Ba2TiO4 on Ba-rich side. The sintered samples underwent an abnormal grain growth, whereby some grains grew faster than others due to the presence of multi-phase structure. It was found that dielectric and ferroelectric properties of BST ceramics strongly depended on grain size, density, phase compositions and defects.", publisher = "Vilnius University, Vilnius, Lithuania", journal = "ECAPD Conference on Application of Polar Dielectrics 2014, Vilnius, Lithuania", title = "Processing-Dependent Dielectric and Ferroelectric Properties of BST Ceramics", pages = "90", url = "https://hdl.handle.net/21.15107/rcub_rimsi_2925" }
Ćirković, J., Vojisavljević, K., Nikolic, N., Tasić, N., Branković, Z., Sreckovic, T.,& Branković, G.. (2014). Processing-Dependent Dielectric and Ferroelectric Properties of BST Ceramics. in ECAPD Conference on Application of Polar Dielectrics 2014, Vilnius, Lithuania Vilnius University, Vilnius, Lithuania., 90. https://hdl.handle.net/21.15107/rcub_rimsi_2925
Ćirković J, Vojisavljević K, Nikolic N, Tasić N, Branković Z, Sreckovic T, Branković G. Processing-Dependent Dielectric and Ferroelectric Properties of BST Ceramics. in ECAPD Conference on Application of Polar Dielectrics 2014, Vilnius, Lithuania. 2014;:90. https://hdl.handle.net/21.15107/rcub_rimsi_2925 .
Ćirković, Jovana, Vojisavljević, Katarina, Nikolic, Nenad, Tasić, Nikola, Branković, Zorica, Sreckovic, Tatjana, Branković, Goran, "Processing-Dependent Dielectric and Ferroelectric Properties of BST Ceramics" in ECAPD Conference on Application of Polar Dielectrics 2014, Vilnius, Lithuania (2014):90, https://hdl.handle.net/21.15107/rcub_rimsi_2925 .