Si⁺-implanted Si-wire waveguide photodetectors for the mid-infrared

Area of Science:

• Photonics
• Optoelectronics
• Semiconductor Devices

Background:

• Silicon photonics is a key technology for integrated circuits.
• Mid-infrared (mid-IR) wavelengths offer unique advantages for sensing and communication.
• Developing efficient and CMOS-compatible photodetectors for the mid-IR is crucial.

Purpose of the Study:

• To demonstrate CMOS-compatible silicon waveguide p-i-n photodetectors.
• To operate these photodetectors at room temperature and mid-IR wavelengths (2.2–2.3 µm).
• To characterize their responsivity, dark current, and frequency response.

Main Methods:

• Fabrication of Si⁺-implanted Si-waveguide p-i-n photodetectors.
• Room temperature characterization of device performance.
• Measurement of responsivity, dark current, photocurrent linearity, and frequency response.

Main Results:

• Demonstrated CMOS-compatible photodetectors operating at 2.2–2.3 µm.
• Achieved responsivity of 9.9 ± 2.0 mA/W at 5 V reverse bias.
• Reduced dark current to < 1 nA after annealing.
• Measured a frequency response of ~1.7 GHz.

Conclusions:

• Si⁺-implanted Si-waveguide p-i-n photodetectors are viable for mid-IR applications.
• The demonstrated devices offer potential for new communication bands in photonic integrated circuits.
• Room temperature operation and CMOS compatibility enhance their practical applicability.