Abstract: A new citrate gel-processing route to synthesize pure BMT powder at low-temperature (600℃) was proposed and investigated by XRD, DTA and
SEM methods, in which self-prepared Ta-citrate was adopted as the starting precursor. The conventional approach from high purity Ta₂O₅ powder
was also as starting material to prepare BMT powder for comparison. It was discovered that a pure BMT phase with pseudocubic perovskite strcuture was
formed at much lower temperature (600℃) and nano-particle size powder (100～200nm) was obtained by the citrate gel-process. Whereas, the synthesizing
temperature of conventional one was more than 1250℃.

Key words: BMT microwave dielectrics, citrate-gel process, low-temperature synthesis