ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
A middle permittivity dielectrics with the tunable temperature coefficient of dielectric constant(τε) in the BaO-TiO2-Nb2O5 system, Ba3Ti5Nb6O28, has been synthesized and characterized. Thedielectric properties of Ba3Ti5Nb6O28 measured at 1MHz are as follows: dielectric constant (εr) ~38,dielectric loss (tanδ)〈0.0002, temperature coefficient of dielectric constant (τε)~-22ppm/°C. TheBa3Ti5Nb6O28 phase satisfies the requirements of NP0 (MLCC) dielectrics, but the sintering temperatureof the Ba3Ti5Nb6O28 phase (1250~1300°C) is too high to be co-fired with Ag or Cu electrodes. To lowerthe sintering temperature, an appropriate amount of ZnO-B2O3 frit (5~7wt.%) was added to theBa3Ti5Nb6O28 phase and dense ceramics were obtained at the sintering temperature lower than 1000°C.Furthermore, the CaNb2O6 phase with the positive τε of 65ppm/°C was incorporated into theBa3Ti5Nb6O28 phase to adjust the temperature coefficient of dielectric constant from negative topositive(-22~30ppm/°C). Near zero τε ceramics with high εr (38) and low tanδ (0.0002) were obtained atthe composition of Ba3Ti5Nb6O28/ CaNb2O6/ ZB frit=76:17:7 wt.%
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/56/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.368-372.170.pdf
Permalink