Dielectric properties of MgB2O6 (B5+=Nb, Ta, Sb) at microwave frequencies

Microwave dielectric properties of MgB2O6 (B5+ = Nb, Ta, Sb) and their solid solutions have been investigated to control the temperature coefficient of resonant frequency (TCF) of MgTa2O6 ceramics. At the composition range of single phase, TCF of the sintered specimens was depended on the distortion of oxygen octahedra by the substitution of Nb and/or Sb for Ta of MgTa2O6. For the Mg(Ta1-xNbx)2O6 (0.2 ≤ x ≤ 0.8) and Mg(Ta1-xSbx)2O6 (0.1 ≤ x ≤ 0.4) sintered specimens, the quality factor (Qf) was decreased with x content. The dielectric constant (K) of the sintered specimens was dependent on the dielectric polarizabilities.