近年來，隨著半導體產業的發展，半導體元件與矽晶圓整合愈來愈受到重視，光連結系統是相當有潛力的一個方向。鍺錫合金的特點為隨著錫濃度的改變，可以使鍺錫合金變成直接能隙材料，同時鍺錫合金可與矽晶圓有良好整合。由於鍺錫與矽之間的晶格常數差異，使得鍺錫合金與矽晶圓的異質整合得仰賴於磊晶技術的改進，但製程中所累積的熱積存無法避免地會使鍺錫元件與積體電路之間的整合變得更加困難。
　　快速熱熔磊晶法是一種應用於異質整合的方法，透過快速熱熔磊晶法，可以製作出矽鍺錫異質整合元件，藉由矽波導的光學耦合，我們成功製作出高耦合效率之鍺錫波導光偵測器，同時維持鍺錫合金的結晶品質，並拓展傳統鍺光偵測器光響應的波長範圍，透過金屬-半導體-金屬光偵測器的結構，使元件具備高速運作的可能。利用快速熱熔磊晶法製作鍺錫金屬-半導體-金屬光偵測器，特點在於製程簡易花費低、高結晶品質、低熱積存、高相容性以及高頻寬。

　　As development of semiconductor industry, monolithic integration of silicon and other semiconductor devices is attracting significant interest. For optical interconnects to silicon chips, germanium-tin (GeSn) alloy is one of the most promising solutions due to its beneficial properties, such as the potential to become direct bandgap and compatibility with CMOS technology. Conventionally, GeSn alloy is grown by molecular beam epitaxy (MBE). However, thermal budget problem in epitaxy diminishes the compatibility with integrated circuits (ICs).
　　Rapid melt growth (RMG) is a good processing method to realize hetero-integration with small thermal budget. By using RMG method, we successfully fabricate single-crystalline GeSn waveguide photodetectors on a SOI wafer with high-efficiency optical coupling. Due to tin-alloying, the detection wavelength of GeSn photodetectors is extended to 2000nm. Metal-semiconductor-metal (MSM) devices have the advantages of simple process and high-speed response. GeSn MSM photodetector fabricated by RMG is featured with simple process, low cost, high crystallinity, small thermal budget, good compatibility and high bandwidth.

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