本文利用有限元素理論，分析埋入式圓頂型Ge/Si0.69Ge0.3C0.01/Si量子點異質結構之應變分佈行為。首先測試相異形狀與表面量子點的情況，以評估建立模型的實用性。若探討不同截面比值的量子點分析模型，則可發現液靜壓應變（hydrostatic strain）於不同截面幾何之量子點內部保持定值，而雙軸性應變（biaxial strain）則與量子點的截面比具有高度相關性。

覆蓋層的厚度以及量子點的截面幾何對垂直關聯現象扮演重要的因素。量子點垂直關聯性的程度會隨著間隔層厚度的增加而減弱，且關聯位置將隨截面比值增大而逐漸偏離量子點中心。除此之外，若考慮雙量子點系統，則次層量子點原子亦有擴散至兩量子點中央間隔區域的傾向。針對相關參數對應變分佈的影響，可藉本文的分析結論，解釋量子點異質結構的物理特性。

We calculated the strain distributions in capped domed Ge/Si0.69Ge0.3C0.01/Si quantum dots heterosystem using finite-element method. For practicability we examined the cases of different island shape, with and without covered models. After that we compared with the models having variant truncation factors. Results show that the hydrostatic component of the strain is almost remains unchanged within the dots, while the biaxial strain is very sensitive to the truncation factor. One can therefore use strain to tailor the band structure according to the needs for a particular application.

Factors such as the thickness of the spacer layer and the truncation factor of the island are found to play an important role in the vertical self-organized growth. The vertical correlation decreases with the increase in cap layer thickness, and deviates from the center of cap layer surface with the island having larger truncation factor. Besides, the effects of two dots are also discussed. All results within the study could provide useful suggestions.

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