Highly efficient electroluminescence from Si quantum dot/SiO₂ multilayer light-emitting devices via phosphorus/boron...

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Silicon-based light emission devices face challenges in achieving high efficiency for monolithic optoelectronic integration.
• Improving electroluminescence intensity is crucial for advancing silicon photonics.

Purpose of the Study:

• To enhance the electroluminescence intensity and efficiency of silicon quantum dots (QDs).
• To reduce the turn-on voltage and improve light extraction efficiency in silicon light-emitting devices.
• To investigate the impact of phosphorus (P)/boron (B) co-doping on silicon QD optoelectronic properties.

Main Methods:

• Co-doping of silicon quantum dots with phosphorus (P) and boron (B).
• Fabrication of silicon light-emitting devices with and without co-doping.
• Utilizing a nanostructured silicon substrate to improve light extraction.
• Electroluminescence measurements and stability testing.

Main Results:

• Co-doping increased electroluminescence intensity nearly tenfold compared to undoped devices.
• Turn-on voltage decreased from 15V (undoped) to 6V (co-doped) and 3V (nanostructured substrate).
• Observed a redshift in electroluminescence peak post co-doping; achieved 1.02% power efficiency and 4.9% external quantum efficiency.

Conclusions:

• Phosphorus/Boron co-doping significantly enhances the optoelectronic quality of silicon QDs.
• Co-doped silicon nanomaterials demonstrate high stability and potential for integrated silicon photonics.
• Reduced turn-on voltage and improved efficiency pave the way for practical silicon-based light emitters.