在本研究中，我們使用固態法成功合成Ba1-xSrxTi0.9Ga0.1O3樣品，其中x=1%～7%。我們對A-site Ba(上標 2+)進行Sr(上標 2+)取代後，樣品的結構由六方相→混合相→四方相，這結果是與熱力學報導相符合。其中Sr(上標 2+)大於2%後無六方相純相，在Sr(上標 2+)較高摻雜時，則只有四方相存在，此結果也與室溫拉曼結果吻合。在微波特性分析上，隨著摻雜量的增加，Qxf 值與K值都有大幅下降，明顯因為晶相轉變（六方→四方），表示只要有四方晶產生，則Qxf值與K值就會有很大的下降值產生，這也說明了六方相鈦酸鋇（h-BTO）具有良好的微波特性，有極高的應用價值。
The Ba1-xSrxTi0.9Ga0.1O3 samples are synthesized by the solid state method in air with x=1%~7% in this work. The structure of samples are changed from hexagonal to mixed phases then tetragonal through the A-site substituting process, which is consistent with the thermodynamic prediction on literature. The samples can form the pure hexagonal structure when the Sr-concentration is lower than 2%, but the structures of samples are only tetragonal in the higher Sr-doping region, which is consistent with the room temperature Raman spectrum measurements. The microwave property measurement are showed that because the main phase of samples will change from hexagonal to tetragonal with the Sr-doping level increasing, which is due to the Qxf value and K value of samples are dramatic dropping with Sr-concentration increasing. It means that if the samples are included the tetragonal structure, whose Qxf value and K value are hugely decreasing, so it also proofs that the hexagonal BaTiO3 material has very good microwave property and a large potential for application.
