Thin Amorphous $\hbox {Si/Si}_{3}\hbox {N}_{4}$ -Based Light-Emitting Device Prepared With Low Thermal Budget

This letter reports for the first time on an electrically pumped silicon light-emitting device with a thin multilayer stacked amorphous silicon (alpha-Si, in thickness of 3-7 nm)/silicon nitride (~10 nm) structure. The observed photoluminescence (PL) is tunable from ~700 to ~670 nm, and intensity increases by decreasing the alpha-Si thickness. The PL intensity can be enhanced through postdeposition annealing at relatively low temperatures and a short annealing time (e.g., as optimized at 700degC/10min). Electroluminescence from devices that are built upon the proposed structure originates from electron-hole pair recombination, and the carrier injection mechanism is through Frenkel-Poole tunneling. Our proposed structure, being highly complimentary metal-oxide-semiconductor compatible, benefits from a low thermal budget process coupled with an accurate layer thickness control.