High-performance GeSn-on-SOI photodetector grown by selective epitaxy for C+L application

In this work, we demonstrate a high-performance GeSn photodetector fabricated on a silicon-on-insulator substrate using selective epitaxial growth. This method effectively confines the growth of the GeSn material to predefined regions, which enhances material quality and facilitates large-scale integration. The fabricated photodetector exhibits a high responsivity of 0.53 A/W and 0.23 A/W at 1550 nm and 1630 nm, respectively. Furthermore, the device demonstrates a low dark current density of 0.35 A/cm² and a bandwidth of 16 GHz. These results indicate that GeSn grown by selective epitaxy is capable of fabricating high-performance devices.