本研究利用射頻磁控濺鍍法(RF sputtering)在ITO玻璃基板上製作LaGdO3薄膜，並利用電子束蒸鍍法製作Al金屬作為上電極，使元件結構成為MIM(Metal - Insulator - Metal)電容。整個實驗分為兩主軸方向，分別是介電材料之應用以及電阻式記憶體之研究。在介電薄膜之研究方面分為三大部分，第一個部分為探討LaGdO3介電薄膜在不同基板溫度下製作之物性與電性分析。根據實驗結果發現，LaGdO3薄膜在基板溫度400℃時有最佳的膜厚均勻性，以及較佳的介電特性，接著我們比較電極退火與否對於電特性之影響，由TEM微結構分析中發現，在電極退火200℃時，在電極與介電薄膜間出現明顯的氧化鋁層，而此氧化鋁層的出現會使得元件整體電容值下降，因此，我們選擇了電極未退火處理來做為後續研究之參數。
在第二部分的實驗中，我們探討了不同退火溫度對於LaGdO3薄膜之物性及電性影響。根據實驗結果，在不同的退火溫度下，LaGdO3薄膜皆呈現結晶態，而在退火500℃時得到較平滑之表面(Rrms：3.87nm)、在可見光波段之光學穿透率約為80%、在頻率1 MHz時的電容密度約為0.42 μF/cm2 (k~23.9)、介電損耗則是0.85、漏電流密度約在10-8 A/cm2(外加偏壓15 V時)。在漏電流機制分析中發現，在中段電場時符合普爾-法蘭克發射機制，較高電場時則符合蕭特基發射機制，不同退火溫度的光學能隙皆約為5.85 eV。此外，我們亦建立了等效電路模型來描述我們所製作的MIM電容器。
在第三個部份的實驗中，我們探討了不同退火氣氛對於LaGdO3薄膜之物性及電特性影響。於實驗結果中發現，在氮氫氣氛下(95% N2+5% H2)退火，有較為平滑表面(Rrms：3.83)，在可見光波段穿透率約為80%，除此之外，擁有較佳的介電特性，在頻率1 MHz下，電容密度為0.51 μF/cm2、介電損耗值為0.24，亦可以利用Goswami-Goswami等效電路模型來描述。在漏電流分析的部分，因為較多氧空缺之影響，於外加偏壓10 V時約為10-4 A/cm2。
在另一個主軸，電阻式記憶體的研究部分，我們以Al/LaGdO3/ITO/glass此結構，製作電阻式記憶體，發現在限制電流0.01 A時，具有單極性之電阻轉換特性，有四個數量級以上的開關比(on/off ratio)，在漏電流機制分析方面，此單極性轉換之電阻式記憶體在低阻態時是歐姆傳導機制、高阻態則是空間電荷傳導機制。

In this research we choose the rare earth ternary oxide as the gate dielectric material for the transparent microelectronic application. We deposit the LaGdO3 thin film on the ITO/glass substrate by RF sputtering and select the Al metal as the top electrode. The first part of this research is the dielectric properties about Al/LGO/ITO/glass structure, and the second part is the resistive switching property. According to physical and electrical analysis, the thin film with substrate temperature 400℃ and electrode unanneled exists the better electrical characteristics and uniform morphology. In the effect of annealing temperature analysis, we found that 500℃ is the better annealing temperature with smooth morphology、higher permittivity (K~23.9@1MHz)、less dissipation factor (0.85@1MHz)、lower leakage current density(10-8 A/cm2 @15 V)and 80% transmittance in the visible spectral region. There are some trade-off problems in the different annealing atmosphere. For instance, the sample annealed in N2-H2 atmosphere shows the higher dielectric properties than samples annealed in air or pure oxygen but existing worst leakage current density which is attributed to more oxygen vacancy in the film. On the other hand, the on/off ratio of unipolar RRAM can reach above 4 orders that’s enough for memory application. In the end, we consider that LaGdO3 thin film applies on ITO/glass transparent substrate will be the potential material for the transparent electronic circuit.

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