本論文中，我們以AES (Auger electrum spectrum) 作為主要分析儀器來探討該儀器在表面材料中的應用，實驗內容分為兩個部分。
第一部分，我蒸鍍鍺烯薄膜到銀樣品上，並用AES來分析樣品上的薄膜厚鍍，發現在鍺烯作為主要被觀測材料時會因為鍺的歐傑電子產生率不高導致誤判，因此在觀測低厚鍍薄膜時必須要使用不同的方法來檢測薄膜的厚度。本論文使用的方法為觀測基材的峰值訊號變化來估計薄膜的厚度，我利用銀的訊號作為主要的測量對象，並用Python 來fitting 原始AES能譜上的銀峰值變化。然而分析後發現，似乎無法單純以銀的峰值做為參考來推估薄膜厚度，因為AES的複雜性導致量測上會被多種因素影響，其中包括表面的狀態、覆蓋層的相變等原因，仍需要大量實驗來證明其他效應影響程度。
第二部分，我們用AES來掃描整個樣品來確定薄膜或是原子在整個樣品上面的分布情況，在這個部分，我將矽鍍在銀樣品上，然後觀測整個樣品上的矽原子分布。實驗二中，我們的分析方法是比較簡單的訊號百分比，即用矽與銀的峰值變化來換算樣品上兩種材料的百分比。結果發現矽原子在樣品上時，我們加熱樣品不只會使矽原子在表面移動，還會使矽原子往更深層移動並卡在銀單晶的內部。對比光電子能譜後，也確定樣品裡有矽原子存在，說明此一用法是可以應用在薄膜材料中。

In my Master-program research, I use Auger electron spectroscopy (AES) as the main technique to study its application to 2D layers grown on substrates. The experimental subject is divided into two parts. In the first part, we deposited Ge to grow germanene on Ag(111), and analyze the coverage dependence of the Auger peak intensity for Ge. However, I found that Auger peak intensity for Ge was too low to distinguish from the background signal so instead, I investigated the coverage dependence of Auger peak intensity for Ag to estimate the coverage of germanene. I used Python program to fit the Ag peak line shape in the original AES spectrum. Shirley background was applied in the fitting. The resulting relation between Ag peak intensity versus Ge deposition time shows that the Ag peak intensity decays smoothly but when the coverage increases to about 1 ML, the Ag peak intensity undergoes abrupt decrease. In comparison with the corresponding coverage dependence of low energy electron diffraction (LEED) patterns, I discovered that this abrupt drop in Ag peak intensity indicates the phase transition from striped-phase (SP) germanene to quasi-freestanding phase (QP) germanene. In the second part, we used AES to scan the entire sample area to determine the distribution of Si atoms on Ag(111). In light of relative signal percentage, which uses the peak intensity ratio between Si and Ag to represent the distributing percentage of the Si atom on Ag(111). The results indicate that upon heating, Si atoms don’t just expand their distributing area on the Ag(111) surface, but also imbed them into deep Ag layers. The emission-angle dependence of Si oxide core- level peak measured my photoemission spectroscopy indicates the consistent behavior.

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