Role of yttrium and magnesium in the formation of core-shell structure of BaTiO3 grains in MLCC

• Published in: Journal of the European Ceramic Society Vol. 28; no. 6; pp. 1213 - 1219
• Main Authors: KIM, Chang-Hoon, PARK, Kum-Jin, YOON, Yeo-Joo, HONG, Min-Hee, HONG, Jeong-Oh, HUR, Kang-Heon
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier 2008
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Capacitors; Ceramic industries; Chemical industry and chemicals; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Electrotechnical and electronic ceramics; Exact sciences and technology; Technical ceramics; Scanning electron microscopy; Core shell structure; Capacitors; BaTiO3; Yttrium addition; Titanates; Ceramic capacitor; Experimental study; Electron microscopy; X ray diffraction; Oxide ceramics; Magnesium addition; Additive; Transmission electron microscopy; Sintering; Barium Titanates; Fabrication structure relation; Manufacturing; Microstructure; Electroceramics
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2007.09.042

To understand the contribution of additive elements in the formation of the core-shell structure in BaTiO3 (BT) grains in multilayer ceramic capacitors, specimens were prepared with BT powders mixed with Y and Mg, and their microstructures were investigated by SEM, XRD and TEM. The additives inhibited growth of the BT grains, leading to a much reduced sinterability for Y addition. Microstructural investigation showed that Y dissolved easily in the BT lattice to a certain depth inside the grain, whereas Mg tended to stay at grain boundaries rather than to be incorporated into BT. It was considered that, added in a proper ratio, Y could play a dominant role in the formation of shells, leading to a slight dissolution of Mg in the shell. 16 refs.