在鐵電材料中，鐵酸鉍(BiFeO3，BFO)是同時在室溫下具有鐵電性和反鐵磁性的材料，具有做成元件的潛力。但BFO仍有漏電流問題需克服，故本研究目的是想找導電的氧化物材料來當底電極層，期望克服此問題，並討論兩種材料製作過程所遇到的問題及薄膜特性。
本研究企圖在SrTiO3 (STO)基板上成長Nd1.85Ce0.15CuO4+y (NCCO)氧化物磊晶薄膜，當作底電極，在其上成長多鐵性BiFeO3 (BFO)薄膜。NCCO單層膜以及BFO/NCCO/STO多層結構，均以射頻磁控濺鍍製備，所用之NCCO和BFO靶材則籍由固態反應燒結而成。為達到磊晶成長之目的，我們嘗試了多種濺鍍參數，并進行後續退火處理。成長於(001)STO基板上之NCCO單層膜雖有明顯的(001)擇優取向，但其中仍有少許的(110)取向，而NCCO的(110)晶粒由於晶格匹配的關係，在隨後的BFO成長中會誘導二次相Bi24Fe2O39的生成，導致BFO薄膜成長失去控制，無法形成磊晶。在電性方面，霍爾量測證實所成長之NCCO薄膜有很高的導電率，足以作爲電極。

In this work, Nd1.85Ce0.15CuO4+y (NCCO) was studied as the bottom electrode for the epitaxial growth of multiferroic BiFeO3 (BFO) films on the SrTiO3 (STO) substrates. The growth of the single NCCO layer on (001) STO substrate, as well as the BFO/NCCO/STO multilayers, was attempted by the RF magnetron sputtering. The NCCO and BFO targets used in the sputtering deposition were homemade via the solid-state reaction method. Various growth parameters were studied in order to obtain epitaxial films. The phase purity, texture, surface morphology and electrical conductivity of the sputtered NCCO films were examined by X-ray diffraction, scanning electron microscopy and Hall-effect. The effects of the NCCO film property on the subsequent BFO film growth and its ferroelectric property were also studied.

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