Dual-frequency CMOS terahertz detector with silicon-based plasmonic antenna

Area of Science:

• Terahertz (THz) technology
• Semiconductor device fabrication
• Plasmonics

Background:

• Multi-frequency Terahertz (THz) detectors are crucial for advanced imaging and sensing.
• Existing THz detectors face limitations in sensitivity and integration.

Purpose of the Study:

• To propose and fabricate a novel dual-frequency THz detector.
• To enhance THz wave absorption and detector responsivity.
• To enable compact, high-density array integration for THz systems.

Main Methods:

• Fabrication of a stacked dual-frequency THz detector using standard CMOS technology.
• Integration of a silicon-based plasmonic antenna and a metal-based antenna.
• Excitation of localized surface plasmon resonance using heavy-doped polysilicon.

Main Results:

• Achieved maximum voltage responsivity of ~2000 V/W (silicon antenna) and ~450 V/W (metal antenna) at 220 GHz and 650 GHz.
• Demonstrated low noise equivalence power of 23 pW/Hz^0.5 and 110 pW/Hz^0.5.
• Confirmed the detector's compact size suitable for high-density array integration.

Conclusions:

• The novel dual-frequency THz detector offers significantly enhanced performance.
• The silicon-based plasmonic antenna design improves THz wave absorption and responsivity.
• This compact detector is well-suited for scalable THz imaging and sensing systems.