利用快速熱熔磊晶法(RMG)於矽基板上製備鍺錫合金結構，探討其材料特性。我們以RMG法製備出直條狀結構，因為錫的熔點較低，所以在磊晶過程中會被推至尾端最後固化析出，因此直條狀結構尾端會有明顯的鍺錫分界面，以致於高濃度鍺錫合金分布集中在邊界處，且遠離純錫界面合金濃度會急劇下降。我們將針對直條狀結構距成核窗不同位置下微光致發光(Micro-PL)的光譜量測，探討其濃度變化，並以微拉曼(Micro-Raman)量測結果互相比對。
因為鍺錫合金只分布在直條狀結構尾端幾個微米的範圍，而為了能有大面積、高濃度的鍺錫合金，我們試著在鍍膜時增加錫的濃度，利用RMG法製備大面積排列的柱狀結構，並以SEM以及TEM分析其磊晶情形與鍺錫合金的濃度分布狀況，另外加入非晶矽層來測試改善鍺錫合金的濃度分布情況。

The material properties of GeSn structures fabricated on Silicon substrate by Rapid-Melt-Growth (RMG) method was investigated. We fabricated several GeSn strips, and because of the lower melting point of Sn, it would be pushed to the end of the strip and then solidified during the liquid phase epitaxial process. Therefore, there would be a varying concentration of Sn distributed inside the GeSn strip. We measured the Micro-Photoluminescence (Micro-PL) spectra at different locations from seed window of the strip and analyzed the concentration of Sn. In addition, the above results were compared with the results obtained from Micro-Raman spectroscopy.
In order to have large-area, high-concentration of GeSn alloy on Si substrate by RMG method, we fabricated a large-area GeSn rod array and analyzed the crystal quality and element concentration in each rod by SEM and TEM. Besides, we studied the RMG process on the GeSn alloy with an amorphous silicon (a-Si) layer cap and evaluated the influence on the Sn distribution.

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