GaAs/AlGaAs core multishell nanowire-based light-emitting diodes on Si

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Integrating III-V semiconductors with silicon is crucial for advanced electronic and photonic devices.
• Gallium arsenide (GaAs) nanowires offer unique properties for optoelectronic applications.
• Current methods for integrating nanowires on silicon face challenges in scalability and performance.

Purpose of the Study:

• To develop a method for direct fabrication of GaAs nanowire-based light-emitting diodes (NW-LEDs) on silicon substrates.
• To investigate the electroluminescence (EL) properties of these integrated NW-LEDs.
• To explore the potential for monolithic integration of III-V nanowires on silicon.

Main Methods:

• Selective-area metalorganic vapor phase epitaxy (SA-MOVPE) was employed for direct fabrication.
• Vertically aligned GaAs/AlGaAs core-multishell nanowires with radial p-n junctions were grown.
• An NW-LED array was fabricated directly on the Si substrate.

Main Results:

• Successfully integrated vertically aligned GaAs/AlGaAs core-multishell NW-LED arrays on Si.
• Achieved a low threshold current for electroluminescence (EL) of 0.5 mA (approx. 0.4 A/cm²).
• Observed superlinear increase in EL intensity with current, indicating superluminescence.

Conclusions:

• The developed SA-MOVPE technique enables direct fabrication of NW-LEDs on Si.
• The observed superluminescence demonstrates the potential of these devices for efficient light emission.
• This technology opens possibilities for monolithic and on-chip integration of III-V nanowires on silicon.