Solid‐state synthesis of compositions from the Bi2O3–TeO2 system show that, under an oxygen atmosphere, Te4+ oxidizes to Te6+ and yields four room‐temperature stable compounds: Bi2Te2O8, Bi2TeO6, ...Bi6Te2O15, and new a compound with the nominal composition 7Bi2O3·2TeO2. Dense ceramics can be prepared from all these compounds by sintering between 650° and 800°C under an oxygen atmosphere. The permittivity of these compounds varies from ∼30 to ∼54, the Q×f value from 1.100 to 41.000 GHz (∼5 GHz), and the temperature coefficient of resonant frequency from −43 to −144 ppm/K. Bi6Te2O15 and 7Bi2O3·2TeO2 do not react with silver, and, therefore, they have the potential to be used for applications in low‐temperature cofired ceramic (LTCC) technology.
Using X-ray diffraction analysis, scanning electron microscopy, thermogravimetry, and measurements of the dielectric properties up to the MW frequency range, the characterization of Bi sub(2)Ti ...sub(3)TeO sub(12), Bi sub(2)TiTeO sub(8), and Bi sub(6)Ti sub(5)TeO sub(22) compounds, which all include Te super(6+), was performed. As the processes of Te super(6+) reduction and the evaporation of TeO sub(2)-containing species contribute to the presence of secondary phases, the preparation of single-phase ceramics is rather difficult. To minimize the amount of secondary phases during the firing process, the pellets were muffled in a corresponding compound and then fired in an autoclave furnace under 10 bars of oxygen pressure. By sintering the Bi sub(2)Ti sub(3)TeO sub(12), Bi sub(2)TiTeO sub(8), and Bi sub(6)Ti sub(5)TeO sub(22) between 840 and 1010C, ceramics with e sub(r) ranging from 36 to 350, Q x f values from 220 to 12 500 GHz, and t sub(f) from +41 to +2600 ppmK were obtained.
Using X-ray diffraction analysis, scanning electron microscopy, thermogravimetry, and measurements of the dielectric properties up to the MW frequency range, the characterization of ..., ..., and ... ...compounds, which all include ..., was performed. As the processes of ... reduction and the evaporation of ...-containing species contribute to the presence of secondary phases, the preparation of single-phase ceramics is rather difficult. To minimize the amount of secondary phases during the firing process, the pellets were muffled in a corresponding compound and then fired in an autoclave furnace under 10 bars of oxygen pressure. By sintering the ..., ..., and ... between 840... and 1010...C, ceramics with ... ranging from 36 to 350, Q x f values from 220 to 12 500 GHz, and ... from +41 to +2600 ppm/K were obtained. (ProQuest: ... denotes formulae/symbols omitted.)
Using X‐ray diffraction analysis, scanning electron microscopy, thermogravimetry, and measurements of the dielectric properties up to the MW frequency range, the characterization of Bi 2 Ti 3 TeO 12 ..., Bi 2 TiTeO 8 , and Bi 6 Ti 5 TeO 22 compounds, which all include Te 6+ , was performed. As the processes of Te 6+ reduction and the evaporation of TeO 2 ‐containing species contribute to the presence of secondary phases, the preparation of single‐phase ceramics is rather difficult. To minimize the amount of secondary phases during the firing process, the pellets were muffled in a corresponding compound and then fired in an autoclave furnace under 10 bars of oxygen pressure. By sintering the Bi 2 Ti 3 TeO 12 , Bi 2 TiTeO 8 , and Bi 6 Ti 5 TeO 22 between 840° and 1010°C, ceramics with ɛ r ranging from 36 to 350, Q × f values from 220 to 12 500 GHz, and τ f from +41 to +2600 ppm/K were obtained.
Using X‐ray diffraction analysis, scanning electron microscopy, thermogravimetry, and measurements of the dielectric properties up to the MW frequency range, the characterization of Bi2Ti3TeO12, ...Bi2TiTeO8, and Bi6Ti5TeO22 compounds, which all include Te6+, was performed. As the processes of Te6+ reduction and the evaporation of TeO2‐containing species contribute to the presence of secondary phases, the preparation of single‐phase ceramics is rather difficult. To minimize the amount of secondary phases during the firing process, the pellets were muffled in a corresponding compound and then fired in an autoclave furnace under 10 bars of oxygen pressure. By sintering the Bi2Ti3TeO12, Bi2TiTeO8, and Bi6Ti5TeO22 between 840° and 1010°C, ceramics with ɛr ranging from 36 to 350, Q×f values from 220 to 12 500 GHz, and τf from +41 to +2600 ppm/K were obtained.
Using X‐ray diffraction analysis and scanning electron microscopy it was revealed that in an atmosphere of flowing oxygen in the temperature range 700°–800°C, three new compounds are formed in the ...Bi2O3–TiO2–TeO2 pseudoternary system. These compounds are Bi2Ti3TeO12, Bi2TiTeO8, and Bi6Ti5TeO22, and all the compounds include Te6+. All three crystal structures were solved and refined using X‐ray powder diffraction data. Based on the results of the phase formation, a solid‐state compatibility diagram is proposed.
Solid-state synthesis of compositions from the Bi2O3-TeO2 system show that, under an oxygen atmosphere, Te4+ oxidizes to Te6+ and yields four room-temperature stable compounds: Bi2Te2O8, Bi2TeO6, ...Bi6Te2O15, and new a compound with the nominal composition 7Bi2O3.2TeO2. Dense ceramics can be prepared from all these compounds by sintering between 650 degrees and 800 degrees C under an oxygen atmosphere. The permittivity of these compounds varies from 30 to 54, the Q x f value from 1.100 to 41.000 GHz (5 GHz), and the temperature coefficient of resonant frequency from -43 to -144 ppm/K. Bi6Te2O15 and 7Bi2O3.2TeO2 do not react with silver, and, therefore, they have the potential to be used for applications in low-temperature cofired ceramic (LTCC) technology. PUBLICATION ABSTRACT
Solid‐state synthesis of compositions from the Bi 2 O 3 –TeO 2 system show that, under an oxygen atmosphere, Te 4+ oxidizes to Te 6+ and yields four room‐temperature stable compounds: Bi 2 Te 2 O 8 , ...Bi 2 TeO 6 , Bi 6 Te 2 O 15 , and new a compound with the nominal composition 7Bi 2 O 3 ·2TeO 2 . Dense ceramics can be prepared from all these compounds by sintering between 650° and 800°C under an oxygen atmosphere. The permittivity of these compounds varies from ∼30 to ∼54, the Q × f value from 1.100 to 41.000 GHz (∼5 GHz), and the temperature coefficient of resonant frequency from −43 to −144 ppm/K. Bi 6 Te 2 O 15 and 7Bi 2 O 3 ·2TeO 2 do not react with silver, and, therefore, they have the potential to be used for applications in low‐temperature cofired ceramic (LTCC) technology.
Using X‐ray diffraction analysis and scanning electron microscopy it was revealed that in an atmosphere of flowing oxygen in the temperature range 700°–800°C, three new compounds are formed in the Bi ...2 O 3 –TiO 2 –TeO 2 pseudoternary system. These compounds are Bi 2 Ti 3 TeO 12 , Bi 2 TiTeO 8 , and Bi 6 Ti 5 TeO 22 , and all the compounds include Te 6+ . All three crystal structures were solved and refined using X‐ray powder diffraction data. Based on the results of the phase formation, a solid‐state compatibility diagram is proposed.
Using X-ray diffraction analysis and scanning electron microscopy it was revealed that in an atmosphere of flowing oxygen in the temperature range 700-800C, three new compounds are formed in the Bi ...sub(2)O sub(3)-TiO sub(2)-TeO sub(2) pseudoternary system. These compounds are Bi sub(2)Ti sub(3)TeO sub(12), Bi sub(2)TiTeO sub(8), and Bi sub(6)Ti sub(5)TeO sub(22), and all the compounds include Te super(6+). All three crystal structures were solved and refined using X-ray powder diffraction data. Based on the results of the phase formation, a solid-state compatibility diagram is proposed.
