隨著3C產業的發展,可攜式電子產品在日常生活中開始扮演重要的角色,並接著帶動了記憶體的演進。鐵電記憶體是相當被看好的一種非揮發性記憶體,以MFIS場效電晶體作為主要結構的鐵電記憶體除了具有非揮發性,還具有高耐久度、低能耗、以及操作快速的特性,因而獲得高度的重視。目前為止己經有許多不同的研究團隊分別使用了不同的鐵電材料及絕緣材料來建構MFIS結構,並針對其特性做研究及分析。包括PZT、SBT、BLT、YMO…等不同的鐵電材料以及HfO2、Y2O3…等不同的絕緣材料己被大量研究。在本實驗中,我們使用了化學液相沉積法(chemical solution deposition),在p-type的矽基板上鍍製了單相的氧化鋯(ZrO2)及鐵酸鉍(BiFeO3)薄膜。在我們的實驗中,使用了不同的熱處理條件,以及不同的摻雜原子來改變MFIS結構的特性,並藉此得到一個最佳的處理條件。在我們的實驗中,我們發現在As-Deposited的氧化鋯上鍍製鐵酸鉍,並且以氧氣氛在攝氏五百度之下進行熱處理,所完成的MFIS結構可在±6V的電壓下獲得約0.78V的記憶窗口,雖然還不算太大,但以鐵酸鉍的高極性及高矯頑場,相信這個材料仍有相當大的發展空間。
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