A series of polycrystalline Ga-doped Barium titanate (BaTi1-xGaxO3) were synthesized for the studies on the dopant-concentration dependence of Raman spectra and dielectric properties. The Qxf value of Ga-doping samples increases up to about 20% of Ga concentration, but the dielectric constant (K-value) decreases while the A(1g) phonon mode (636 cm(-1)) experiences an increasing red-shift. The phonon mode becomes soft with Ga-ion increasing, and the FWHM of Raman peak increases with Ga-ion increasing until tetragonal structure appeared. The effective ionic weight, ionic radii and Coulomb interaction are important influences, which induce the chemical pressure and reduce the excess charge in Ti-site in the Ga-doping h-BaTiO3 system. The relation between Raman mode shifter and K-value, and the correlation of the Qxf value and the FWHM of related phonon vibrations have been reported and examined.
