Preparation of Nano BaTiO₃-Based Dielectric Ceramics by Different Sintering Methods

Abstract:

Microstructure control in thin-layer multilayer ceramic capacitors (MLCCs) is one of the nowaday challenges for increasing capacitive volumetric efficiency and high voltage dielectric properties. In this paper, the ultrafine-grained BaTiO3 dielectric ceramics with uniform grain size distribution were prepared by chemical coating approach. The doping effects of rare-earth element (Ho) on the microstructures and dielectric properties of the ceramics were investigated. The addition of Ho in nano BaTiO3-based ceramics was found to improve the temperature coefficient of capacitance (TCC) performance, which could be attributed to a significant reduction in the grain size. Moreover, the effects of two-step sintering (TSS) method on the microstructures and dielectric properties, compared with conventional sintering (CS) method, were also discussed. The dielectric constant of ceramics sintered by the TSS method was higher than that of ceramics prepared by CS method. The results reveal that the adoption of TSS method could control the grain size and suppress the abnormal grain growth more effectively, which improves the TCC characteristics.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 1136-1141
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.1136
• Online since: June 2012
• Authors: Hui Ling Gong, Xiao Hui Wang, Jin Yong Kim, Zhi Bin Tian, Guo Feng Yao, Long Tu Li
• Keywords: BaTiO₃, Dielectric Property, Microstructure, MLCCs

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