Silicon-based emitters and detectors have long been desired owing to the possibility of monolithic integration of photonics with high-speed Si electronics and the aspiration of broadening the reach of Si technology by expanding its functionalities well beyond electronics. To overcome the intrinsic problem of bandgap indirectness in the group-IV semiconductors of Si, Ge, and SiGe alloys, a new group-IV material platform Silicon-Germanium-tin alloy (SiGeSn) has been investigated, which features: 1) the industry scalable growth; 2) compatible with current Si complementary metal-oxide semiconductor (CMOS) process; 3) capability of monolithic integration on Si; 4) the identified group-IV based direct bandgap materials; and 5) the tunable bandgap allowing the optoelectronic devices operation covers broad wavelength in near- and mid-infrared ranges. For the past decade, plenty of promising results have been reported, such as GeSn lasers based on direct bandgap GeSn alloys, GeSn light emitting diodes (LEDs) and detectors operating in 2~3 µm. With tremendous novel electrical, optical, and mechanical properties, the newly developed GeSn devices could dramatically change the landscape of future microelectronics and photonics.

In this work, the following aspects have been reported: 1) The material growth of SiGeSn by commercially available reduced pressure chemical vapor deposition (CVD) system. The maximum Sn composition of 22% was achieved; 2) The demonstration of GeSn optically pumped laser. The lasing coverage from 2 to 3 μm was achieved at Sn composition ranging from 8.0 to 22%; 3) The investigation of GeSn-based PIN photodiodes, based on which the light emitting diodes (LEDs) and photodetectors were characterized. The specific detectivity (D*) of GeSn detector is only one order of magnitude lower than current market dominating detectors that are made from III-V materials.