Highly efficient electroluminescence from Si quantum dot/SiO₂ multilayer light-emitting devices via phosphorus/boron co-doping and surface nano-structuring

Enhancing emission efficiency presents a challenge for Si-based light emission devices in all-silicon monolithic optoelectronic integration. This study introduces phosphorus (P)/boron (B) co-doping to significantly increase the electroluminescence intensity of Si quantum dots (QDs)-nearly tenfold compared to undoped devices. The turn-on voltage drops from 15 V for undoped to 6 V for co-doped devices and further reduces to 3 V with a nanostructured Si substrate to improve light extraction efficiency. The redshift of electroluminescence peak after co-doping is also observed, and the possible mechanism is briefly discussed. Stability tests show power efficiency up to 1.02% and maximum external quantum efficiency of 4.9%. These findings demonstrate the superior optoelectronic quality and stability of silicon nanomaterial-based devices, highlighting their potential in integrated silicon photonics.