出版社：Electronics and Telecommunications Research Institute
摘要：The effects of and addition on the microstructures and microwave dielectic properties of system were investigated. or phases were observed for compositions based on BaO/ = 1 ratio. The compositions deviated from ratio were composed of major phases of or , and the compound of and or that of BaO and . The microstructure of ceramic with composition varied from spherical grains to needlelike grains with increasing sintering temperature. With increasing , the optimum sintering temperature with maximum density increased, and the dielectric constant( ) and quality factor(Q) decreased due to the formation of secondary phases. With increasing , the optimum sintering temperature and the dielectric constant decreased with increased Q value. And the temperature coefficient of resonant frequency, shifted toward positive direction. The dielectric ceramics with showed Q values of above 2000 and dielectric constants of above 80 at 3GHz.
