Low-temperature co-firing behavior of novel LiBa3Nb3Ti5O21 ceramics

LiBa₃Nb₃Ti₅O₂₁ ceramics were sintered at 1075&deg;C, and the XRD pattern showed that the LiBa₃Nb₃Ti₅O₂₁ ceramics had a single-phase structure, in addition, no other phases were generated. Excellent microwave dielectric properties were obtained: <i>&epsilon;</i><i>_r</i>=70.8, <i>Q</i>×&#402;=12281GHz, &tau;_&#402;=88ppm/&deg;C. LBBS glass is used as a sintering aid to reduce the sintering temperature of LiBa₃Nb₃Ti₅O₂₁ ceramics. The LiBa₃Nb₃Ti₅O₂₁ ceramics doped with 4wt.% LBBS glass were successfully sintered at 925&deg;C and obtained good microwave dielectric properties: <i>&epsilon;_r</i>=53.4, <i>Q</i>&times;&#402;=8281GHz, &tau;_&#402;=92ppm/&deg;C. In order to further confirm that the ceramics meet the LTCC technical requirements, SEM tests were performed on the samples. Backscattered electron images as well as EDS map scans show that LiBa₃Nb₃Ti₅O₂₁ ceramics doped with 4wt.% LBBS glass do not react with Ag and Ag does not diffuse in the ceramic matrix. Therefore, LiBa₃Nb₃Ti₅O₂₁ ceramics doped with 4wt.% LBBS glass meets the LTCC technical requirements and is a competitive candidate for high dielectric constant LTCC.