High-speed III-V nanowire photodetector monolithically integrated on Si

Area of Science:

• Optoelectronics
• Materials Science
• Nanotechnology

Background:

• Direct epitaxial growth of III-V materials on silicon for optical devices remains challenging.
• Nanowires offer III-V material integration but their vertical geometry limits advanced device designs.

Purpose of the Study:

• To demonstrate the in-plane monolithic integration of InGaAs nanostructure p-i-n photodetectors on silicon.
• To achieve high-speed optical data reception and light emission using these integrated devices.

Main Methods:

• Fabrication of 60 nm thin InGaAs nanostructure p-i-n photodetectors on a silicon substrate.
• Characterization of spectral response using free space coupling.
• Testing high-speed data reception and light emission capabilities.

Main Results:

• Photodetectors exhibit spectral response from 1200-1700 nm.
• Devices achieve ultra-low capacitance with footprints as small as ~0.06 μm².
• Demonstrated high-speed optical data reception at 32 Gb/s with a 3 dB bandwidth exceeding 25 GHz.
• p-i-n devices function as light-emitting diodes emitting around 1600 nm.

Conclusions:

• Successful in-plane monolithic integration of InGaAs nanostructure photodetectors on silicon.
• Demonstrated potential for high-speed, compact optical devices for integrated optical links.
• Paved the way for future silicon photonic integrated circuits with advanced optoelectronic functionalities.