In this thesis, we synthesize the BaTi1-xCoxO3 sample (x=0.05, 0.10, 0.15, 0.2 and 0.25) with the solid state method and all samples are sintering in air. The structures of Co-doping samples are formed hexagonal structure with x<0.25 when the sintering temperature is increasing.
All sample are analyzed by powder X-ray diffraction and the “Rietveld profile-fitting method”, the all Co-dpoing compounds are the same symmetric space group (P63/mmc). During the substituting processing, the volume of unit cell of BaTi1-xCoxO3 samples are decreasing with the Co-ions increasing because the ion-radius of Co3+ is smaller the Ti4+. But the a-axis length is a bit contraction; the c-axis length is slightly extension.
The room temperature Raman spectrum measurements are also showed that the tetragonal modes of BaTi1-xCoxO3 will go away and the intensity of hexagonal modes of BaTi1-xCoxO3 systems are increasing with sintering temperature increasing. The atomic weight of Co is lighter than Ti, so the hexagonal vibration modes of Co-doping samples are toward higher wave-number with Co -concentration increasing.
The RF impedance analyzer and microwave property measurement are reported that the Co-ion is smaller than the Ti-ion which can increase the internal tension of the unit cell, so it generates that the Qxf value are hugely decreasing with Co-doping level increasing. But the K value is just a little to decreasing.
