Structural, optical band gap, microwave dielectric properties and dielectric resonant antenna studies of Ba_(1-x)La_(2x/3)ZrO_3 (0 ≤x ≤ 0.1) ceramics

摘要

The structural properties of the Ba_(1-x)La_(2x/3)ZrO_3 system were investigated by means of XRD, FT-Ranun and FTIR. The XRD analysis demonstrated that lattice parameter gradually decreased with increase of La content. Raman analysis intended the formation of higher degree of symmetry to increase of La~(3+) conteiu. It was also confirmed from FTIR analysis. The optical band gap was found to be decreased from 3.55 eV to 3.01 eV with increase of La~(3+) content. The surface morphology was studied by the SEM. The microwave dielectric constant and quality factor were investigated by the method as proposed by Hakki-Coleman. The microwave dielectric constant decreased from 38.40 to 30.47 and the value of τ_f changed from 384.71 ppm/℃ to 165.41 ppm/℃ The Q×f values increased from 5731 to 9031 with increase of La~(3+) content. The dielectric resonator antenna (DRA) was investigated experimentally and numerically using a monopole antenna through an infinite ground plane and Ansoft's high frequency structure simulator software, respectively. The required resonance frequency and bandwidth of DRA were investigated in the composition between 0 ≤x ≤0.1.