caa a22 4500 445828390 CHVBK 20180317145306.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s10854-010-0247-z doi (NATIONALLICENCE)springer-10.1007/s10854-010-0247-z Study of the structural and dielectric properties of Bi2O3 and PbO addition on BiNbO4 ceramic matrix for RF applications [Elektronische Daten] [J. Almeida, T. Fernandes, A. Sales, M. Silva, G. Júnior, H. Rodrigues, A. Sombra] In this paper, the structural and dielectric properties of BNO (BiNbO4) was investigated as a function of the external RF frequency and temperature. The BNO Ceramics, prepared by the conventional mixed oxide method and doped with 3, 5 and 10 wt. % Bi2O3-PbO were sintered at 1,025°C for 3h. The X-ray diffraction patterns of the samples sintered, shown the presence of the triclinic phase (β-BNO). In the measurements obtained at room temperature (25°C) was observed that the largest values of dielectric permittivity (ε′ r ) at frequency 100kHz, were for the samples: BNO5Bi (5 wt. % Bi2O3) and BNO5Pb (5 wt. % PbO) with values ε′ r ~ 59.54 and ε′ r ~ 78.44, respectively. The smaller values of loss tangent (tan δ) were for the samples: BNO5Bi and BNO3Pb (3 wt. % PbO) with values tan δ ~ 5.71×10−4 and tan δ ~ 2.19×10−4, respectively at frequency 33.69MHz. The analysis as a function of temperature of the dielectric properties of the samples, obtained at frequency 100kHz, showed that the larger value of the relative dielectric permittivity was about ε′ r ~ 76.4 at temperature 200°C for BNO5Pb sample, and the value smaller observed of dielectric loss was for BNO3Bi sample at temperature 80°C, with about tan δ ~ 5.4×10−3. The Temperature Coefficient of Capacitance (TCC) values at 1MHz frequency, present a change of the signal from BNO (−55.06ppm/°C) to the sample doped of Bi: BNO3Bi (+86.74ppm/°C) and to the sample doped of Pb: BNO3Pb (+208.87ppm/°C). One can conclude that starting from the BNO one can increase the doping level of Bi or Pb and find a concentration where one have TCC=0ppm/°C, which is important for temperature stable materials applications like high frequency capacitors. The activation energy (H) obtained in the process is approximately 0.55eV for BNO sample and increase with the doping level. These samples will be studied seeking the development ceramic capacitors for applications in radio frequency devices. Springer Science+Business Media, LLC, 2010 Almeida J. Physics Department, Federal University of Ceará, UFC, 60455-760, Fortaleza, CE, Brazil aut Fernandes T. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut Sales A. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut Silva M. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut Júnior G. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut Rodrigues H. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut Sombra A. Physics Department, Federal University of Ceará, UFC, 60455-760, Fortaleza, CE, Brazil aut Journal of Materials Science: Materials in Electronics Springer US; http://www.springer-ny.com 22/8(2011-08-01), 978-987 0957-4522 22:8<978 2011 22 10854 https://doi.org/10.1007/s10854-010-0247-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10854-010-0247-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Almeida J. Physics Department, Federal University of Ceará, UFC, 60455-760, Fortaleza, CE, Brazil aut NATIONALLICENCE 700 1- Fernandes T. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut NATIONALLICENCE 700 1- Sales A. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut NATIONALLICENCE 700 1- Silva M. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut NATIONALLICENCE 700 1- Júnior G. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut NATIONALLICENCE 700 1- Rodrigues H. Telecommunications and Materials Science and Engineering Laboratory (LOCEM), Fortaleza, Brazil aut NATIONALLICENCE 700 1- Sombra A. Physics Department, Federal University of Ceará, UFC, 60455-760, Fortaleza, CE, Brazil aut NATIONALLICENCE 773 0- Journal of Materials Science: Materials in Electronics Springer US; http://www.springer-ny.com 22/8(2011-08-01), 978-987 0957-4522 22:8<978 2011 22 10854 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer