Modified Uni-Traveling-Carrier Photodetector with Its Optimized Cliff Layer

Area of Science:

• Optoelectronics
• Materials Science
• Electrical Engineering

Background:

• High-speed and high-power photodetection is critical for modern communication and sensing systems.
• Existing photodetector designs often face trade-offs between speed and power handling capabilities.
• Electric field management within photodetectors significantly impacts their performance characteristics.

Purpose of the Study:

• To design and simulate a novel photodetector, the MUTC-PD (Monolithic Ultrafast Traveling-Carrier Photodetector), with optimized performance.
• To investigate the effect of cliff layer thickness on the electric field distribution and photocarrier dynamics.
• To achieve simultaneous high-speed and high-power response in a single photodetector device.

Main Methods:

• Device design and simulation of the MUTC-PD with varying cliff layer thicknesses.
• Analysis of electric field pre-distortion and electron velocity saturation under increasing light power.
• Characterization of differential capacitance and its relation to device bandwidth.
• Simulation of 3 dB bandwidth and saturation RF output power at different configurations.

Main Results:

• An optimized 70 nm cliff layer in a 16μm MUTC-PD significantly suppressed electric field collapse.
• Simulations demonstrated a maximum 3 dB bandwidth of 137 GHz at -5 V, a substantial improvement over a 64 GHz device with a 30 nm cliff layer.
• The device achieved a saturation RF output power of 27.4 dBm at 60 GHz, indicating excellent high-power handling.

Conclusions:

• The optimized MUTC-PD design effectively enhances electron velocity and device bandwidth by managing electric field dynamics.
• The MUTC-PD demonstrates a promising pathway for achieving simultaneous high-speed and high-power photodetection.
• This design offers significant advancements for applications requiring superior optoelectronic performance.