The role of Cuo-Mo_x in low-fire high dielectric ceramics for multilayer capacitors

Abstract

CuO-based oxide mixtures were selected as sintering aid for (Ba,Ca)(Ti,Zr)O₃ ceramics. Both microstructure and dielectric properties of were remarkably influenced by BaCO₃-CuO flux type. With 1 wt % additive of BaCuO₂-2.5CuO eutectic phase, (Ba,Ca)(Ti,Zr)O₃ ceramics give high dielectric constant of 11000 and uniform grain size of 4–10 üm when sintered at 1130°C for 1 h. Different kinds of CuO-MO_x mixtures were also used to investigate the role of MO_X metal oxide in the grain growth and densification of CuO-added (Ba,Ca)(Ti,Zr)O₃ ceramics. The eutectic temperature between CuO and MO_X plays an important key in microstructure evolution. Both dielectric properties and microstructure can be further modified with doping secondary oxides.

Keywords:

• barium titanate
• liquid phase sintering
• barium copper oxide
• dielectric constant