奈米維度金屬氧化過程及機制是個重要的研究課題，如果金屬氧化將會損害其本身的功能和壽命，尤其當奈米金屬材料成長在半導體上作為導電等運用 (contacts and interconnects)，氧化將會造成接觸面之鬆弛或缺陷，進而產生電力耗損，所以了解奈米金屬成長在基板氧化後的結構及其介面之變化是迫切需要的事情。我們利用特殊的射頻磁控濺鍍製程使鋅量子點同調成長在矽(111)基板上及即時反射式二次諧波來觀察鋅量子點的氧化過程，結構完全被矽(111)表面侷限的鋅量子點和氧化後所形成的氧化鋅球殼將會貢獻3m對稱點群的極化在反射式二次諧波的結果，雷射光班面積下量子點多於1010顆，由整體的淨極化強度之改變來評估不同尺寸所造成結果變化。氧化將會導致鋅量子點尺寸減少及鋅和矽(111)介面發生應力鬆弛的現象，使二次諧波訊號改變。藉由同步輻射XRD分析可以得知量子點氧化後之晶體取向，FE-SEM觀察其表面形貌，XPS縱深分析其鋅和氧的成分比例。因此，我們將進一步解決奈米維度金屬量子點成長在半導體上的氧化問題，可以作為未來奈米元件製程上的參考。

It is a significant issue to research the oxidation process and mechanisms of metallic nanoparticles. When the nanoscale metallic components are oxidized, it will damage their functions and life time. Particularly, metallic nanoparticles are grown on the semiconductor components as contacts or interconnects. The oxidation may result in the relaxation or void defects of metal nanocontacts, and then reduce the conductivity. It is important to study structural changes of metallic nanoparticles grown on the substrate and their interface after oxidation. We used strategic RF magnetron sputtering to fabricate Zinc quantum dots coherently grown on the Si (111) substrate and in-situ analyzed the oxidation process of Zn quantum dots by reflective second harmonic generation (RSHG). Fully constrained Zn dots and sequent oxidized ZnO shell contributed 3m symmetrical dipole to RSHG pattern. The spot area of pump laser would cover more than 109 dots and exhibited net symmetrical dipole contribution to RSHG pattern which depended on the constrain degree of Zn quantum dots constrained Si (111). The oxidation phenomena would lead to the reduction of Zn core and relax the stress between Zn dots and Si (111), which caused the change in RSHG pattern. Synchrotron X-ray diffraction (XRD) patterns could confirm RSHG result and give the evolution of all possible crystal orientations in the oxidization. Besides, we utilized the field emission - scanning electron microscope (FE-SEM) to observe the micrographs and the depth scan of X-ray photoelectron spectroscopy (XPS) spectra to realize the microstructure of Zn/ZnO core-shell quantum dots via oxidation, respectively. As a result, we further solve the key problem of the oxidation of metallic dots grown on semiconductor as the reference of nano device in the future.

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