| Title |
Structural and Microwave Dielectric Properties of the Mg_5B_4O_{15} (B=Ta, Nb) Ceramics with Sintering Temperature |
| Authors |
이승준(Lee, Sung-Jun) ; 김재식(Kim, Jae-Sik) ; 이성갑(Lee, Sung-Gap) ; 이영희(Lee, Young-Hie) |
| Keywords |
cation-deficient perovskite ; Mg_5Ta_4O_{15} ; Mg_5Nb_4O_{15} ; quality factor |
| Abstract |
In this study, both structural and microwave dielectric properties of the Mg_5B_4O_{15} (B=Ta, Nb) cation-deficient perovskite ceramics with sintering temperature were investigated. All sample of the Mg_5B_4O_{15} (B=Ta, Nb) ceramics were prepared by the conventional mixed oxide method and sintered at 1400°C~1500°C. The bulk density and quality factor of the Mg_5B_4O_{15} (B=Ta, Nb) ceramics were increased with increasing sinterning temperature in the range of 1400°C~1450°C, but these were decreased the sintering temperature of above 1450°C. The dielectric constant of the Mg_5Ta_4O_{15} ceramics was increased continuously with increasing sintering temperature. And the dielectric constant of the Mg_5Nb_4O_{15} ceramics was increased in as the sintering temperature increasesfrom 1400°C~1450°C but was decreased at the temperatures above 1475°C. In the case of the Mg_5Ta_4O_{15} and Mg_5Nb_4O_{15} ceramics sintered at 1450°C for 5h, the dielectric constant, quality factor, and temperature coefficient of the resonant frequency (TCRF) were 8.2, 259,473 GHz, -10.91ppm/°C and 14, 37,350 GHz, -52.3ppm/°C, respectively. |