Electrically Injected GeSn Laser with Dual-layer SiN Stressor

The realization of monolithically integrated silicon-based light sources has long been constrained by technological bottlenecks. Owing to its intrinsic compatibility with CMOS processes, germanium (Ge) has emerged as a promising material for silicon-based emitters. By introducing tensile strain and tin (Sn) doping, Ge can be transformed from an indirect-bandgap semiconductor into a direct-bandgap material, thus enabling monolithic laser integration on a CMOS-compatible platform. Here, we propose an electrically injected GeSn laser structure incorporating a dual-layer SiN stressor. We achieve efficient lasing by employing a dual-layer SiN stressor combined with a low Sn content. Simulation results indicate that, at room temperature, the proposed laser exhibits a threshold current density of 104 kA/cm2, an electro-optical conversion efficiency of 6%, and an emission wavelength centered at 2252 nm. This study presents a viable strategy for developing Group-IV silicon-based light-sources.