InGaAs membrane plasmonic photodetector with Ni-InGaAs alloy integrated on Si waveguide.

Area of Science:

• Photonics and optoelectronics
• Materials science
• Semiconductor device physics

Background:

• Silicon photonics offers high integration potential but lacks efficient on-chip photodetectors.
• III-V/Si hybrid integration is a promising approach to overcome silicon's limitations.

Purpose of the Study:

• To develop a high-speed, integrated photodetector for silicon photonics.
• To demonstrate the effectiveness of Ni-InGaAs alloy as an electrode for plasmonic waveguides.
• To simplify the fabrication process for hybrid plasmonic waveguide photodetectors.

Main Methods:

• Fabrication of a III-V/Si hybrid plasmonic waveguide photodetector incorporating an Indium Gallium Arsenide (InGaAs) membrane.
• Utilizing a Nickel-Indium Gallium Arsenide (Ni-InGaAs) alloy as an electrode.
• Characterization of device performance, including responsivity, dark current, and high-speed operation.

Main Results:

• The Ni-InGaAs alloy was confirmed to function effectively as an electrode for plasmonic waveguides.
• A simplified fabrication process enabled the integration of plasmonic waveguide photodetectors onto the Si photonics platform.
• Achieved a responsivity of 0.13 A/W at 1 V with a dark current of 400 nA.
• Demonstrated a 32.1 Gbit/s clear eye diagram, indicating high-speed capability.

Conclusions:

• The proposed III-V/Si hybrid plasmonic waveguide photodetector shows significant potential for high-speed applications in silicon photonics.
• The Ni-InGaAs alloy facilitates simplified integration and effective electrode function.
• This work paves the way for advanced optoelectronic integrated circuits on silicon platforms.