Pb_xSr_(1-x)TiO_3陶瓷及薄膜的制备和性能研究

Preparation and Properties of Pb_xSr_(1-x)TiO_3 Ceramics and Thin Films

研究了Pb的摩尔分数对PbxSr1-xTiO3（x=0．2～0．8）陶瓷微结构和介电性能的影响，当x〈0．45时晶体为立方相，x≥0．45时为四方相；随着Pb的摩尔分数增大，陶瓷气孔率下降，致密度增加，晶粒尺寸逐渐增大，居里峰近似线性地向高温方向移动，并具有一致的居里外斯常数。采用射频磁控溅射法在Pt／Ti／SiO2／Si（100）上制备了Pb0.3Sr0．7TiO3（PST30）薄膜，经550℃退火后为（111）择优取向的多晶薄膜，1kHz下的可调率为21．8％。

PbxSr1-xTiO3（x=0.2-0.8） ceramics are prepared, and the effect of the Pb content on the microstructure and dielectric properties are studied. X-ray diffraction studies show that the lattice structure changes from cubic to tetragonal phase at 45 % Pb content. Scanning Electron Microcopy studies indicate that the higher Pb content is, the greater grain size and the higher density is. εr-T curve exhibits that Curie-Temperature linearly increases with the increase of Pb content and the compositions （x = 0.20- 0.55 ） show the similar Curie-Wiess constant. Pb0.3Sr0.7TiO3 thin film are prepared by RF magnetron sputtering on Pt/Ti/SiO2/Si（100） substrate and annealed at 550 ℃. Meanwhile, the films exhibit （111） orientation and the tunability is measured to be 21.8% at 1 kHz.