半導體材料中的空位缺陷會降低半導體元件的性能，然而經常使用的表徵工具很難去定量測量出它們的密度，常見的定量方法有阿基米德法(Archimedes method)、熱膨脹差 分 法 (Differential thermal expansion method) 以 及 正 電 子 湮 滅 譜 (Positron annihilation spectroscopy)，但它們都難以達到奈米尺度。
之前我們已經成功地證明掃描式電子顯微鏡(Scanning Electron Microscope, SEM)中的直接熱吸收測量可用於奈米級的原子序分析，在此篇論文中，我進一步的探討此方法是否具有定量空位缺陷濃度的能力。我首先利用 CASINO Monte Carlo program 模擬缺陷變化與熱吸收的關係，並藉由 Si3N4 奈米線堆疊出來的凹凸處與陽極氧化鋁(Anodic Aluminum Oxide, AAO)樣品的表面缺陷進行驗證，接著比較直接熱吸收平台中的低應力(Low-stress)、多矽(Si-rich)的氮化矽(SiNx , 0 < x <1.33)與一般氮化矽(Si3N4)奈米線發現因矽含量的多寡造成兩種同樣的化合物其熱吸收有所差異。我利用 Si3N4奈米線求得 SiNx 中的 x，並且檢測 SiC 奈米粒子與奈米線中的缺陷，其空位缺陷是使用螢光(Photoluminescence, PL)光譜來識別的。我最後量化了 SnS 樣品的空位缺陷並配合阿基米德法進行驗證。根據以上結果我成功的證明掃描式熱吸收電子顯微術是具有在奈米尺度定量空位缺陷濃度的能力。

In semiconductor materials, vacancy defects can reduce the performance of semiconductor devices. However, it is difficult to quantitatively measure their density using commonly used characterization techniques. Common quantitative methods include the Archimedes method, differential thermal expansion method, and positron annihilation spectroscopy. However, they are difficult to achieve at the nanoscale.
In our previous work, we successfully demonstrated that direct thermal absorption measurement in scanning electron microscopy (SEM) is suitable for nanoscale atomic composition analysis. In this study, I further investigated whether this method has the capability to quantitatively analyze vacancy defects. I first simulated the relationship between defect variations and thermal absorption using the CASINO Monte Carlo program. I validated my findings by examining the surface defects of Si3N4 nanowires fabricated with an uneven surface and anodic aluminum oxide (AAO) samples. I then compared the thermal absorption of low stress, Si-rich SiNx (0 < x < 1.33) nanowires with conventional Si3N4 nanowires. I found that the silicon content in the two compounds led to differences in thermal absorption. By determining the value of x using Si3N4 nanowires, I detected defects in SiC nanoparticles and nanowires, whose vacancy defects are identified using photoluminescence (PL). Finally, I quantified the vacancy defects in SnS samples and validated them using the Archimedes method. Based on these results, I successfully demonstrated that scanning thermal absorption electron microscopy has the capability for quantitative vacancy defect analysis at the nanoscale.

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