本研究主要探討矽鍺奈米線和鎳進行固態反應，藉由臨場觀察的方式探討反應發生的機制。
首先針對矽鍺奈米線進行性質的分析，使用顯微拉曼光譜鑑定其內部鍵結，藉由光譜上約400 cm-1處的峰值判定矽鍺合金鍵結，並使用TEM分析與EDS量測判定矽鍺奈米線中的矽鍺含量比值，本實驗所使用的矽鍺奈米線之鍺含量約為10%。
之後利用臨場加熱之穿透式電子顯微鏡可以成功使矽鍺奈米線和鎳金屬在450 ℃下發生反應，並記錄下反應過程，計算成長速率為0.46 nm/s及反應活化能為0.708 eV / atom，使用球面像差修正掃描穿透式電子顯微鏡分析反應物的成分與結構，觀察到正交晶系的Ni2Si生成。在加入氧化鋁阻礙層後，成長速率減緩，鎳的擴散變得緩慢使得反應機制受到影響並產生NiSi與Ni2Si兩種生成物。此外，於加熱後發現，矽鍺奈米線與鎳反應後會有斷裂的情形產生，根據EDS分析了解其斷裂受到鍺元素成份的影響。

In CMOS technology, the metal silicides/germanides have prominent advantages such as low resistivity, high thermal stability, and chemical stability. Here, we conducted the study to probe the phase transformations and the diffusion behavior of Ni in Si1-xGex nanowire (NW) by in-situ transmission electron microscope (TEM).
First, the structural analysis of the Si1-xGex NW was carried out by Raman spectrum and TEM. From Raman results, the vibration mode at ~400 cm-1 is confirmed to be the Si-Ge bonding. Additionally, we affirmed the Ge content of 10% in the Si1-xGex NW by TEM and energy-dispersive X-ray spectroscopy (EDS).
Afterwards, the Si1-xGex NWs was dispersed on TEM Si3N4 membrane and contacted with Ni by E-beam lithography process for in-situ study. The sample was then heated to the 450 ℃, Ni diffused into Si1-xGex NW and formed Ni2Si, the diffusion mechanism is confirmed to be reaction-controlled. The growth rate of Ni2Si formation is 0.46 nm/s and the activation energy is 0.708 eV / atom. On the other hand, we conducted the in-situ study using Al2O3 layer-coated Si1-xGex NW, the Al2O3 layer serves as the diffusion barrier. Importantly, we found that the diffusion mechanism was changed. Furthermore, the Si1-xGex NW would be broken after heating process, which might be due to the segregation of Ge. The results have potentials to provide the insights for device fabrication in semiconducting manufacturing.

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