近年來鍺對於應用在電子元件以及光電元件上的趨勢越來越明顯，利用鍺與矽相對小的晶格差異、較易於整合在傳統矽製程上的特點、電子電洞遷移率是矽的2倍，以及較一般材料能帶較窄、並且藉由拉伸應力可使從間接能隙轉成直接能隙的特點，做出具有高光響應度、高頻率的電子元件。但是矽鍺元件雖然較其它三五族元件有較小的晶格差異，但還是有4.2%以上的晶格不匹配，讓鍺整合在矽製程上有一定的困難度，一般的方法會使用直接磊晶MBE……等製程方法，但是成長時間相對較慢，要付出較長的時間以及昂貴的高真空機台使得在整合上需要付出較大的製程成本。 在本論文中使用的是快速熱熔法來成長，較一般的磊晶有更快速的成長時間且可以整合在前段製程，在SOI基板中向下蝕刻出10X5 µm¬2的區域增加沉積非晶鍺厚度並沉積非晶絕緣層覆蓋非晶鍺區域，將試片利用快速熱熔異質磊晶成長重新排列鍺成為多晶結構，並且降低長晶成本和降低矽/鍺異質接面整合難度，最後整合製作出側向式光感測器，量測其光響應度的特性，且利用TEM及拉曼光譜觀測鍺區重新排列的品質。 ;High-speed communication devices have been developed for many years for the synergy of photonic and electronic signal transmission. Because of the narrow bandgap for infrared light absorption of germanium and its strain-engineered band gap modulation, the incorporation of germanium into silicon-based optoelectronics has attracted more attention. However, germanium has lattice mismatch of 4.2% with silicon. Generally, germanium epitaxy technique is high-cost by MBE and will compound the difficulty of silicon/germanium integration. In this thesis, we use rapid-melting-growth to grow germanium thin film on Si, and then we can obtain high-quality germanium mesa. The film was investigated by TEM and SEM microscopy and Raman spectrum. Moreover, the high-quality silicon/germanium/silicon PIN-photodetector was fabricated and measured to study its I-V characteristics and study the photocurrent and responsivity at near-infrared frequency.
