CERAMICS INTERNATIONAL
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2022
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IF 5.532
Zhiqiang Li,Shiguang Yan,Jiake Xia,Fei Cao,Xuefeng Chen,YunXiong Song,Yonghong Chen,Zhi-Sheng Lin,Genshui Wang
With the increasing demand for the miniaturization, high capacitance and high reliability of the Multilayer Ceramic Capacitor (MLCC), the thickness of single dielectric layer is less than 1 μm and the original partical size of the powder has reached the scale less than 300 nm. In this paper, BaTiO 3 powder of various partical sizes (150–500 nm) was modified with Dy and Ho through a chemical coating method. The dense and uniform ceramics in accordance with EIA X7R-type temperature stability were sintered under low oxygen partial pressure and good dielectric properties of dielectric constant >2000 and dielectric loss <1% were obtained. The grain size effect on the dielectric properties under various dc-bias field were systematically investigated. It is found that the fine-grain ceramic exhibits a lower absolute change of the dielectric constant and a higher dc-bias stability. Furthermore, the modified 150 nm BaTiO 3 powders was made into 1210-type MLCCs, and the dielectric behavior of the MLCCs with different dc-fields and ac-fields were study over −55 °C–125 °C. It is found that the ac electric field had a greater influence on the dielectric properties at room temperature and below, and the dielectric constant variation under a dc-bias field was also greatly advanced for the modified fine-grain MLCCs. The results provide a reference for the design of the next generation of BME-MLCCs.
研究领域:
材料科学
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电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2024
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IF 3.5
Pengfei Wang,Xiong Huang,Jianwei Zhao,Saiwei Luan,Xinyu Fu,Bo Li,Jun Yang,Zhenxiao Fu,Xiuhua Cao,Lei Zhang,Shuhui Yu,Rong Sun
It has generally been believed that the performance of ultra-thin multilayer ceramic capacitors (MLCCs) are mainly controlled by doping elements and the contribution of synthesis approaches of BaTiO 3 (BT) powders can be neglected. However, in this study, we demonstrate that the solid-state powders exhibit a heterogeneous distribution of residual BaCO 3 (BC), TiO 2 , or Ti-rich phases, whereas hydrothermal powders are characterized by a BC surface layer, which can be characterized by nanoinfrared (AFM-IR), and the divergent approaches play an important role in the “core–shell” structure. The BC layer in hydrothermal BT contributes to Ti vacancies during sintering, increasing the “core–shell” ratio in MLCCs. This results in augmented capacitance but reduced performance at elevated temperatures. Conversely, the presence of a Ti-rich phase in solid-state powders induces Ba vacancies, leading to decreased “core–shell” ratios and dielectric constants.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Advanced Dielectrics
·
2023
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IF 3.1
Yan Gu,Faqiang Zhang,Wanghua Wu,Zhifu Liu
Most widely used dielectrics for MLCC are based on BaTiO 3 composition which inevitably shows performance degradation during the application due to the migration of oxygen vacancies ( V o ⋅ ⋅ ). Here, the BaTiO 3 , ( Ba 0 . 9 7 Ca 0 . 0 3 )TiO 3 , Ba( Ti 0 . 9 8 Mg 0 . 0 2 )O 3 , ( Ba 0 . 9 7 Ca 0 . 0 3 )( Ti 0 . 9 8 Mg 0 . 0 2 )O 3 , ( Ba 0 . 9 6 Ca 0 . 0 3 Dy 0 . 0 1 )( Ti 0 . 9 8 Mg 0 . 0 2 )O 3 ceramics (denoted as BT, BCT, BTM, BCTM and BCDTM, respectively) were prepared by a solid-state reaction method. The core-shell structured grains ( ∼ 200 nm) featured with 10-20 nm wide shell were observed and contributed to the relatively flat dielectric constant-temperature spectra of BTM, BCTM and BCDTM ceramics. The TSDC study found that the single/ mix doping of Ca 2 + , especially the Mg 2 + , Mg 2 + /Ca 2 + and Mg 2 + /Ca 2 + /Dy 3 + could limit the emergence of V o ⋅ ⋅ during the sintering and suppress its long-range migration under the electric-field. Because of this, the highly accelerated lifetimes of the ceramics were increased and the value of BCDTM is 377 times higher than that of BT ceramics. The p − n junction model was built to explain the correlation mechanism between the long-range migration of V o ⋅ ⋅ and the significantly increased leakage current of BT-based dielectrics in the late stage of HALT.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Saiwei Luan,Huizhan He,Lei Zhang,Jie Yu,Xiuhua Cao,Jingxi Wang,Zhenxiao Fu,Rong Sun
The use of environmentally friendly aqueous tape casting has emerged as a promising route for fabricating high-quality BaTiO 3 -based films, particularly for ultra-thin multilayer ceramic capacitors (MLCCs). In this study, a high-solids-content BaTiO 3 slurry was formulated using APC (a polycarboxylate ammonium salt) as the dispersant, WB4101 as the acrylic binder, and PL002 as the plasticizer. The resulting 9.50 μm green tape exhibited a high density (3.65 g/cm 3 ), tensile strength (7.65 MPa), and fracture strain (11%), indicating good mechanical integrity. BaTiO 3 -based MLCC chips prepared from this tape showed a room-temperature capacitance of ∼28.0 nF and a dielectric loss of 0.02. Comprehensive evaluations of temperature coefficient of capacitance (TCC), ferroelectric hysteresis, DC-bias-dependent dielectric behavior, and resistivity degradation under accelerated DC stress were conducted. Notably, the TCC satisfied the X7R specification (−55 °C to 125 °C, ΔC/C 25 °C ≤ ±15%), confirming excellent dielectric temperature stability. Ferroelectric hysteresis characteristics, DC-bias-dependent dielectric stability, and resistance to degradation collectively demonstrate the excellent electrical reliability of the material. These results demonstrate that the proposed aqueous tape casting system is effective for producing reliable, high-performance BaTiO 3 -based MLCCs and provides a practical pathway for future development of lead-free, eco-friendly capacitor technologies.
研究领域:
材料科学
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电气工程
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陶瓷材料
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环保技术
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
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2025
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IF 5.6
Han Lin,Liying Qian,Junrong Li,Yu Song
Organic vehicle carbon residue after sintering of copper-terminated electronic pastes for multilayer ceramic capacitors (MLCC) under nitrogen atmosphere has been a challenge. In this work, thermal degradation of ethyl cellulose with different molecular weights was investigated using TG-FTIR, and it is found that the volatilization rate of CH 4 and CO 2 of ethyl cellulose rose with the increase of molecular weight, and the residual rate of ethyl cellulose with 5.0 × 10 4 was only 1.29 % at 800 °C. The molecular weight of ethyl cellulose also shows a great influence on the rheological properties of copper terminal paste, the phase angle of copper pastes gradually decreases with the increasing molecular weight of ethyl cellulose, from viscous liquid to elastic solid. For the copper terminal paste, which is prepared by ethyl cellulose with molecular weight between 4.6 × 10 4 and 5.0 × 10 4 , the end termination morphology is good and the densification of the sintered copper paste is more than 99.5 %, which has satisfactory rheological and sintering properties. This work clarifies the effect of thickener on electronic paste and provide guidance for the design of organic vehicle and electronic paste.
研究领域:
材料科学
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化学工程
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电子工程
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yetong Lv,Pengfei Wang,Yexia Qin,Jianwei Zhao,Jun Yang,Zhenxiao Fu,Xiuhua Cao,Lei Zhang,Shuhui Yu,Rong Sun
BaTiO 3 -based ceramic is considered to be a fascinating dielectric material with high reliability for ultra-thin multilayer ceramic capacitors (MLCC). Here, we fabricated a series of acceptor-doped BaTiO 3 (Mg: 0.2, 0.5, 1.0, 1.5, 2.0, and 5.0 mol%) ceramics with Al 2 O 3 and SiO 2 as sintering additives. With an increase in Mg concentration, the insulation resistance of the BaTi 1- x Mg x O 3 ceramics initially increases and then decreases, in which the 0.5 mol% Mg-doped ceramic achieves superior degradation behavior. The reason is that with the incorporation of the acceptor ion Mg 2+ , the charge compensation mechanism in the system changes. Initially, barium vacancy is generated, which is gradually dominated by oxygen vacancy . Analysis indicates that the segregation of the acceptor state barium vacancy to the grain boundary increases the schottky barrier of the grain boundary, while the gradual increase of the donor state oxygen vacancy reduces the reliability of the ceramic. This study provides a comprehensive overview illustrating the significant role of point defects in the potential barrier of the grain boundary in acceptor-doped BaTiO 3 ceramics. It identifies a pathway to achieve high reliability in BaTiO 3 -based MLCC.
研究领域:
材料科学
·
陶瓷
·
电气工程
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电介质
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）