奈米金屬點有很高的表體比例，很適合來觀察與氣體反應的現象。由於實驗過程皆在具有氣體的環境下進行，因此無法利用電子束當作偵測方式。而螢光光譜或是拉曼光譜則是因為單層或是物理吸附等條件無法提供對應的訊號。而利用反射式二次諧波來分析奈米金屬點與氣體反應時電偶極矩的改變，我們可以解析出細微的動態變化以及觀察金屬點的完整氧化過程。在此研究中，我們會呈現兩種奈米鋅顆粒的氧化過程，其中腔體內氧化會確保在真空下進行，且會經歷化學吸附並詮釋氧化層建立前的過程。而退火通氧氧化因鋅顆粒有接觸大氣，必須考慮環境濕度（水氣）對其的影響，最後觀察完整氧化的行為。這一個工作是建立在本實驗室具有特色的受局限奈米鋅顆粒在 Si(111) 上的樣本製作與量測方式，同時透過反射式二次諧波及光學量測工具分析，在不同的溫度改變下，其氧氣含量改變有助於化學吸附量的改變並影響完整之氧化程度。這一個工作呈現了在不同溫度與氧氣含量下，化學吸附延伸到氧化層建立，最後鋅顆粒完整氧化的變遷過程。

In this work, we first prepare the collective Zn dots which were deposited on Si(111) substrates by magnetron RF sputtering. The fabrication of set up condition was combined with RF power of 100-120W and negative substrate bias of −500 V, and kept the ratio of hydrogen to argon at approximately 18% in the working chamber with the pressure of 1×10−2 torr. H2 reduces ZnO and removes SiO2 in the strategic RF sputtering, which caused enhancement on the diffusion of Zn adatoms. The size distribution of the dots is strongly dependent on the growth conditions and growth time. Furthermore, we present 2 types of oxidation processes on Zn dots, in-situ oxide observation and take out to annealing in oxygen. In-situ find out the immediately dipole change with oxygen fill in the chamber. Afterwards, when talking about the growth Zn dots is taken out from the chamber, we consider how the outward environment humidity will impact on Zn dots. We using second harmonic generation (SHG) to explain the dipole contribution from the Zn dots, additionally, then X-ray Diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) to see the structure evolution and oxide formation. The rest of the setup and operation method of these experiments are described in. Synchrotron XRD and XPS was performed at the 17B1 and 24A1 stations of the National Synchrotron Radiation Research Center in Taiwan.

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