Ba_5(Nb_(1-x)Sb_x)_4O_(15)微波介电陶瓷的低温烧结

添加质量分数为1%的H3BO3为助烧剂。研究了Ba5(Nb1–xSbx)4O15(0≤x≤0.2)陶瓷的烧结特性、显微结构和微波介电性能。结果表明:当x≤0.15时,该类陶瓷可在900℃附近烧结,并伴有少量BaSb2O6和BaB2O4相;随着x从0增加到0.2,εr和τf均有较大幅度下降;Q.f先升后降。在900℃烧成温度下,x为0.15的陶瓷获得较好的微波介电性能:εr为29.21,Q.f为13 266 GHz,τf为11×10–6℃–1,并能与Ag电极很好相容,基本满足LTCC工艺的要求。

Low temperature sintering of Ba5(Nb1-xSbx)4O15 microwave dielectric ceramics

The sinterability,microstructure and microwave dielectric properties of Ba5(Nb1–xSbx)4O15(0≤x≤0.2) ceramics doped with H3BO3 were investigated.It is found that all of the Ba5(Nb1–xSbx)4O15(x≤0.15) ceramics with the addition of 1 % H3BO3 could be sintered at about 900 ℃.The interactions between Ba5(Nb1–xSbx)4O15 and H3BO3 lead to the formation of BaSb2O6 and BaB2O4 phases.With x increasing from 0 to 0.2,εr and τf decrease greatly.Quality factor increase and then decrease.At a sintering temperature of 900 ℃,the ceramic of Ba5(Nb0.85Sb0.15)4O15 with addition of 1 % H3BO3 exhibite the optimal microwave dielectric properties of εr =29.21,Q.f =13 266 GHz,τf =11×10–6 ℃–1 and good compatibility with silver electrodes,which is a suitable low-temperature cofired ceramic(LTCC).