複雜性氧化物具有十分豐富的物理性質，其中包含了高溫超導、巨磁阻、焦電、壓電、介電、半導、導電、磁性與光性等優異功能特性。在應用層面，這些新穎的功能性往往還能藉由外加的電場、磁場與應力等刺激來進一步調控其外在功能表現，這也提供了未來新興電子元件的開發一個很好的機會。在此之中最具代表性的材料為鋯鈦酸鉛(Pb(Zr1-xTix)O3，PZT)，其具有優異的壓電特性而成為目前工業最常見的電能-力學能轉換元件，目前也有豐富的學術研究試圖進一步提升其可用性。鋯鈦酸鉛除了壓電特性以外在室溫下還具有鐵電特性，根據成長在不同取向的基板會有不同的鐵電電域結構，然而大多數的研究都集中於成長於(100)取向基板之鋯鈦酸鉛薄膜，對於成長於其他取向基板的研究很稀少。在本研究中，我們以成長於(110)取向基板之鋯鈦酸鉛薄膜作為研究材料，我們使用壓電力顯微鏡( Piezoresponse force microscopy, PFM)研究此材料的電域結構並發現此材料具有兩種共存的相，這是在先前的研究沒有被報導過的。此外，我們發現此兩相共存系統還能藉由外加電場的調控達到這兩種相之間的相轉換，顯示此材料有潛力能設計成多功能相轉變記憶體。我們也透過實驗證實兩相的分布與空間電荷有密切的關係，藉由探針注入的電荷使得有效空間電荷的增減是造成兩相轉換的主要物理機制。

Complex oxides provide a variety of intriguing functionalities, including high temperature superconductivity, multiferroics high-dielectricity, colossal magnetoresistance, and so on. Abundant researches related to the modulation of these intriguing phenomena via external stimuli have been accomplished, which provide great insight into the development of next-generation electronic devices. Among these functional materials, Lead zirconate titanate (Pb(ZrxTi1-x)O3, PZT) is the most commonly studied materials in both industry and academic community due to its remarkable piezoelectricity and corresponding adjustability under controllable fabrication conditions. Ferroelectric PZT thin films exhibit very different ferroelectric domain structure dependent on the orientation of epitaxial substrate. However, most of previous researches focus on (100)-oriented PZT system while the researches for others epitaxial orientation remains scarce. In this study, we investigate the ferroelectric domain structure and dynamic switching behavior of (110)-oriented Pb(Zr0.2Ti0.8)O3 thin films by employing piezoresponse force microscopy (PFM). We observe the (110)-oriented PZT behaves an unreported mixed-phase system which is composed of two degenerate phases, T- and M-phase. It is striking to note that a phase transition between T- and M-phase could be driven by the scanning of a biased AFM tip, which indicates the (110)-oriented PZT has potential for the development of novel phase transition memory. Our results also reveals that the mechanism of phase transition and the final configuration of T- and M-phase is dominant by the evolution of the space charge distribution driven by electric field.

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