本論文主要研究具自發極化場的鐵電薄膜對接面能帶產生之影響。透過即時量測隨時變光電子能譜，探測 PZT/LSMO(PbZr0.2Ti0.8O3/La0.7Sr0.3MnO3)異質接面結構。我們證明了界面電荷將導致LSMO界面能帶的彎曲，並可藉由PZT自發極化場方向來調控LSMO界面能帶的彎曲方向。高亮度的同步輻射光可在PZT薄膜中產生的大量光致載子，此光致載子會屏蔽PZT的自發極化場，並調變界面能帶結構。此可藉由觀察來自下層LSMO光電子束縛能隨時間偏移之動態行為。此外，透過 LSMO光電子束縛能隨時間偏移之動態行為，可以得知超薄PZT薄膜的電導率與自發極化場的值。

The electrostatic driven interface band structure between a top ferroelectric-patterned Pb(Zr0.2Ti0.8)O3 (PZT) ultrathin film and a bottom La0.7Sr0.3MnO3 (LSMO) electrode was in situ investigated using a continuous synchrotron radiation photoelectron spectroscopy (SR-PES) measurement. We demonstrate the interface electrostatics affected band bending structure on the LSMO side is reversible by switching the polarization of the PZT side, and can be modulated by SR induced photoelectric effect. Time-dependent polarization screening induced by the photogenerated carriers in top PZT layer was investigated by monitoring the core-level shifting of buried LSMO layer under continuous synchrotron radiation illumination. The dynamic characterization of the buried layer core-level shifting could be a novel method to probe the electric conduction and ferroelectric polarization in ultra-thin PZT film.

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