Microwave dielectric properties of Ba2Ti9O20 materials prepared by reaction sintering process

Barium nanotitanate microwave ceramics obtained by a chemical method

“…To be an efficient material as dielectric resonator (RD), this element should have a high enough electric permittivity to allow miniaturization of components, low dielectric loss and high frequency stability. Among the compounds in the BaO-Ti02 system, barium nanotitanate -Ba2 Ti9020 (BTO) meets these requirements and has received great attention [1][2][3]. Nonetheless, hollandite-like structure Ba2 Ti9020 materials are difficult to obtain due to the preferential formation of secondary phases, such as BaTi409 and BaTisO I ), during the calcinations of BaO-Ti02 mixture.…”

“…Generally, B203 is added to previously crystallized BTO powders. However, during the sintering treatment, reactions between the glass and ceramics may induce compositional changes and/or development of second phases due to local heterogeneities, 978-1-4799-1397-8/13/$31.00 ©2013 IEEE which may deteriorate the microwave dielectric properties [1][2][3][4]. To minimize these drawbacks several preparation methods have been used [4][5][6][7][8][9][10].…”

Low‐Temperature Synthesis and Growth of Bulk Ba2Ti9O20Ceramics on Conducting Substrates for Applications in Integrated Dielectric Resonator Devices

“…However, in the preparation of Ba 2 Ti 9 O 20 , the stoichiometry of the reactants and synthesizing conditions must be precisely controlled, because there are various thermodynamically stable compounds such as Ba 6 Ti 17 O 40 , BaTi 3 O 7 , BaTi 4 O 9 , BaTi 5 O 11 , and Ba 4 Ti 13 O 30 in the vicinity of the desired composition. Reports exist regarding various synthesizing methods, 11–18 the effect of doping 19,20 and glass addition 21–23 on the process temperature, phase formation, and microwave dielectric properties. However, the lowest possible process temperature attained is about 900°C for Ba 2 Ti 9 O 20 –glass composites, which is much higher than what ICs can withstand.…”

“…Ba 2 Ti 9 O 20 is a widely studied DR material [8][9][10] and has received considerable attention for its reasonably good microwave dielectric properties. However, in the preparation of Ba 2 Ti 9 O 20 , the stoichiometry of the reactants and synthesizing conditions must be precisely controlled, because there are various thermodynamically stable compounds such as Ba 6 [11][12][13][14][15][16][17][18] the effect of doping 19,20 and glass addition 21-23 on the process temperature, phase formation, and microwave dielectric properties. However, the lowest possible process temperature attained is about 9001C for Ba 2 Ti 9 O 20 -glass composites, which is much higher than what ICs can withstand.…”