本論文研究目的為優化背散射繞射電子(EBSD)實驗於低加速電壓下之空間解析度，當使用低加速電壓電子束時，背散射繞射電子的數量與強度皆會下降，並伴隨著訊噪比(Signal-noise-ratio)下降、菊池圖譜(Kikuchi pattern)影像品質變差，進而導致獲得之菊池圖譜無法精確計算其空間解析度。因此本論文希望藉由影像處理，來優化低加速電壓下的菊池圖譜品質，使EBSD實驗能於低電壓模式下進行，並且能成功計算空間解析度。
本論文使用Wave-base背景扣除法對原始菊池圖進行背景雜訊扣除，接著選取分析區域(ROI)提取菊池線特徵，以三種影像評估值為扣除背景之菊池圖進行影像品質評分，使用DIC技術分析菊池圖相似度，計算相似度之中位數與偏差值，量化菊池圖品質對相似度分析的影響。同時發現表面積碳的影響，藉由縮短曝光時間減緩表面積碳，提高菊池圖品質，最後利用高斯公式擬合相似度曲線計算EBSD空間解析度。
實驗結果顯示，使用SEM在加速電壓10kV與5kV時，X軸解析度分別為570.3±41.2 nm與229.5±15.1nm，在加速電壓10kV時，Y軸解析度為1406.2±65.6nm；使用FESEM在加速電壓10kV與5kV時，X軸解析度分別為57±6.4 nm與37.4±3 nm，Y軸解析度分別為101.5±7.8 nm與97.6±3.5 nm。

The spatial resolution of EBSD can be improved by the decreasing accelerating voltage. However, this is accompanied by the disadvantages of surface contamination and low S/N ratio of Kikuchi pattern, which lead to difficulties in determination of the spatial resolution.

In this study, we adjusted the exposure time and employed the wave-base background correction to improve the quality of Kikuchi pattern in order to calculate the spatial resolution at low accelerating voltage.

The experimental results show that the X-axis resolution is 570.3±41.2 nm and 229.5±15.1 nm at 10 kV and 5 kV, respectively, and the Y-axis resolution 1406.2±65.6 nm at 10 kV and 5 kV, respectively, using SEM. The X-axis resolution is 57±6.4 nm and 37.4±3 nm at 10 kV and 5 kV, and the Y-axis resolution 101.5±7.8 nm and 97.6±3.5 nm, respectively.

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