Effect of CuO doping on properties of Ba_0.6Sr_0.4TiO₃ ceramics

According to the tolerance factor, CuO doped Ba_0.6Sr_0.4TiO₃ (BSTO) based ceramics were prepared by the traditional ceramic processing. The results show that BSTO based ceramics with 0.5%~4.0% of CuO doping could be sintered at 1200°C, and no other phase was introduced. The dielectric properites menasurements indicated that the dielectric constant of BSTO ceramic increased and the dielectric loss decreased with the increasing of CuO content at room temperature and at low frequency;but at microwave frequencies, the dielectric constant and the dielectric loss both increased with the content of CuO. The tunabilities of all the CuO doped BSTO samples are more than 10% (at 1 kV/mm), especially, the tunability of 1% CuO doped BSTO sample has been up to 13.2% (at 1 kV/ mm).