The microwave dielectric properties of $Bi_{0.97}Tm_{0.03}NbO_{4}$ doped with $V_{2}O_{5}$

마이크로파 유전체 $Bi_{0.97}Tm_{0.03}NbO_{4}$$V_{2}O_{5}$ 첨가에 따른 유전특성

  • Hwang, Chang-Gyu (Department of Materials Engineering, Chungbuk National University) ;
  • Jang, Gun-Eik (Department of Materials Engineering, Chungbuk National University)
  • Published : 2002.11.07

Abstract

The microwave dielectric properties and the microstructures on $Bi_{0.97}Nb_{0.03}O_{4}$doped with $V_{2}O_{5}$ were systematically investigated. $Bi_{0.97}Tm_{0.03}Nb_{0.03}O_{4}$ ceramics sintered at $920-960^{\circ}C$were mainly consisted of orthorhombic and triclinic phases after addition of $V_{2}O_{5}$. The apparent density increased slightly with increasing the $V_{2}O_{5}$ addition. The dielectric $constants(\varepsilon_r)$ also increased with $V_{2}O_{5}$ addition(30-45). The $Q{\times}f_0$ values measured on $Bi_{0.97}Tm_{0.03}NbO_4$ ceramics doped with $V_{2}O_{5}$ were between 2,000 and 12,000[GHz] when the sintering temperatures are in the range of $920-960[^{\circ}C]$. It was confirmed the temperature coefficient of the resonant $frequency(\tau_f)$ can be adjusted from a positive value of $+10[ppm/^{\circ}C]$ to a negative value of $-15ppm/^{\circ}C$ by increasing the amount of $V_{2}O_{5}$. Based on our experimental results, the Bi0.97Tm0.03NbO4(added V2O5) ceramics can be applied to multilayer microwave devices at low sintering temperatures.

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