本實驗研究以溶液合成方法製備氧化鎂薄膜應用於非揮發性電阻式記憶體之研究。
將硝酸鎂六水與乙醇合成之溶液旋轉塗佈在銦錫氧化物(ITO)基板接著爐管退火和沉積白金薄膜，白金與ITO薄膜被用作上、下電極，透過X光繞射光譜儀(XRD) 、原子力顯微鏡(AFM)和場發射掃描式電子顯微鏡(SEM)分析氧化鎂薄膜的晶體結構、表面形貌和粗糙度等等，元件的轉換特性藉由半導體元件參數分析儀分析。
分析結果顯示Pt/MgO/ITO電阻式記憶體是具有Forming-free特性的元件，此記憶體具有良好的高低阻值比(104)和低寫入與抹除電壓(-0.5 V、0.5 V)，在室溫下經過104次切換和5000 秒的資料持久度量測沒有明顯的退化，我們也發現使用單掃方式進行量測，元件的操作電壓(set/reset)分佈(或電壓變化量)和高低阻態的電阻變化量要比雙掃方式小很多。在分析元件的電流傳導機制，低阻態的的漏電流符合歐姆傳導機制，高阻態在小偏壓時是歐姆傳導，而隨著偏壓增大傳導機制轉為空間電荷限制電流主導。
總而言之，本研究之氧化鎂薄膜具有製造簡單、低成本和穩定優越的元件切換特性，在電阻式記憶體應用上具有巨大的潛力

This thesis studied a magnesium oxide(MgO)film prepared by solution-based synthesis method for non-volatile resistive-switching random access memory(RRAM)application.
A Magnesium nitrate hexahydrate and ethanol synthesized solution was spin-coated on a Indium-Tin oxide(ITO)coated glass substrate followed by furnace annealing and Platinum(Pt) film deposition. The Pt and ITO films were used as upper and lower electrodes. X-ray diffraction spectrometer(XRD), atomic force microscope(AFM), and field emission scanning electron microscope(SEM)were used to analyze the MgO film’s crystal structure, surface roughness and morphology etc. The device’s switching characteristics was analyzed by a semiconductor element parameter analyzer.
The test results show that this Pt/MgO/ITO RRAM is a forming-free device. It has a great high to low resistance ratio of more than 104, low writing and erasing voltages (-0.5 V, 0.5 V). No degradation was noticed after performing 104 room temperature switching and 5000 s data retention tests. We also found out that using single sweep method to perform testing, the device’s operating voltage (set/reset) distribution (or voltage variation) and its high/low state resistance variations are much smaller than that using double sweep method. When analyze the device’s current conduction mechanism, the leakage currents of its low resistance state obeys ohmic conduction, and its high resistance state at small bias is also ohmic conducting mode, as the bias increases, its mechanism changes to space charge limited current dominate.
In short, the studied MgO film has a great potential for RRAM application for the advantages of its simple and low cost manufacturing, stable and superior switching performance.

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