采用化学溶液分解法分别制备了锆钛酸铅镧(PLZT)(x/65/35,Pb1-xLax(Zr0.65Ti0.35)O3)单组分薄膜和PLZT梯度薄膜,研究了镧掺杂对PLZT组分薄膜铁电性能的影响。结果表明:PLZT单组分和梯度薄膜具有良好的钙钛矿结构,PLZT-123梯度薄膜比PLZT(2/65/35)单组分薄膜在(111)面具有更好的结晶性能。薄膜结构致密无裂缝,与基片表面紧密结合,界面清晰,且表面平整,薄膜厚度均匀,约为400nm。薄膜的最佳掺镧浓度为2%,PLZT(2/65/35)和PLZT-123薄膜表现出了良好的铁电性能,它们的剩余极化强度为36.65μC/cm2和40.47μC/cm2。实验表明掺镧浓度对薄膜性能有着重要的影响,当掺镧浓度较低时,PLZT单组分和梯度薄膜具有良好的铁电性能,而且平均掺镧浓度相同的梯度薄膜比单组分薄膜具有更加优异的铁电性能。
A series of PLZT(x/65/35) uniform composition thin films and PLZT compositional gradient thin films were obtained by chemical solution decomposition (CSD) method.The influences of La doping on the ferroelectric property of PLZT compositional thin films were investigated.The PLZT uniform composition thin films and gradient thin films displayed the pure perovskite phase,the PLZT-123 gradient thin films displayed better crystallization properties in (111) orientation than the PLZT (2/65/35) uniform composition thin films.The film had densely uniform grains,and its structure was crack-free and compact.The interface was very sharp,and the films had a uniform thickness of 400nm approximately.When the La content was 2%,the PLZT (2/65/35) and PLZT-123 will have the excellent ferroelectric property,the Pr values of two kinds of thin films were 36.65 and 40.47μC/cm2.It was clear that the La content played an important role for the ferroelectric property of PLZT thin films.When the La content was low,the PLZT thin films will have the excellent ferroelectric property,and the gradient thin films had the better ferroelectric property than uniform composition thin films.
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