Zn掺杂制备介电可调PST薄膜

Preparation of Dielectric Tunable Zn-Doped PST Thin Films

采用溶胶凝胶工艺,在ITO透明导电玻璃基板上成功地制备了Zn掺杂的Pb_(0.4)Sr_(0.6)TiO_3(PST)铁电薄膜。XRD结果表明:550℃和600℃不同热处理条件下烧结的薄膜均呈单一的钙钛矿相结构。在不同外加直流电场下测试Zn掺杂PST薄膜的介电性能,研究薄膜的介电可调性与热处理温度及过程的关系。发现550℃条件下制备得到的Zn掺杂PST薄膜几乎没有介电可调性,而在600℃条件下制备的Zn掺杂PST薄膜具有明显的介电可调性。另外,600℃条件下制备的Zn掺杂PST薄膜,其可调性随着保温时间和冷却时间的延长有所增加,介电损耗随保温时间和冷却时间的增大而减小。

Zn-doped PST thin films （Pb0.4Sr0.6）ZnxTi1-xO3-x （x=0-0.12） were fabricated by the alkoxide-based sol-gel process using dip-coating method on ITO/glass substrate. All the thin films formed at the different heat treatment temperatures （550 ℃ or 600 ℃） and with the use of rapid heating and cooling yielded the same single phase of perovskite. DC bias was applied for the Zn-doped PST thin films to investigate the relation between the applied DC bias and dielectric constant. It was showed that tunability and dielectric loss rested with the heat treatment condition. 600 ℃ was the lowest heat treatment temperature at which the PST thin films kept the dielectric tunability. Furthermore, the dielectric tunability of the thin film was controlled by the heat treatment progress： the longer the heat treatment progress time, the lager the tunability. In addition, dielectric loss closely linked to the cooling speed： the faster the thin film cooled, the lager the dielectric loss.