Crystal structure and microwave dielectric properties of new alkaline earth vanadate A(4)V(2)O(9) (A = Ba, Sr, Ca, Mg and Zn) ceramics for LTCC applications

摘要

A(4)V(2)O(9) (A = Ba, Sr, Ca, Mg and Zn) ceramics have been prepared by conventional solid state ceramic route. The phase purity of the samples was confirmed by powder X-ray diffraction technique. Raman spectroscopic studies confirm the existence of (VO4)(3-) vibrational groups in A(4)V(2)O(9) ceramics. The possibility of existence of A(4)V(2)O(9) compositions in the AO-V2O5 binary system was also ascertained. The dielectric constant and quality factor of the ceramics under study were carried out by Hakki and Coleman post resonator and cavity perturbation techniques respectively using a vector network analyzer. Among the A(4)V(2)O(9) compositions, Mg4V2O5 ceramic exhibits good microwave dielectric properties such as low dielectric constant of 6.3, Qxf of 37,263 GHz and negative tau(f) of -43.5 ppm/degrees C at an optimum sintering temperature of 940 degrees C. Powder X-ray diffraction and EDS analyses of the co-fired Mg4V2O5 ceramic sample show excellent chemical compatibility with Ag electrode and hence can be used as a candidate material for LTCC applications. (C) 2016 Elsevier Ltd. All rights reserved.