An Ultrafast Active Quenching Active Reset Circuit with 50% SPAD Afterpulsing Reduction in a 28 nm FD-SOI CMOS...

Area of Science:

• Photon detection
• Semiconductor device physics
• Integrated circuit design

Background:

• Single Photon Avalanche Diodes (SPADs) are crucial for low-light detection but suffer from afterpulsing.
• Afterpulsing, caused by residual carriers, limits SPAD performance in high-count-rate applications.
• Existing quenching circuits often face trade-offs between speed and effectiveness.

Purpose of the Study:

• To present an ultrafast Active Quenching-Active Reset (AQAR) circuit for effective afterpulsing reduction in SPADs.
• To demonstrate the circuit's design and performance in a 28 nm FD-SOI CMOS technology.
• To validate the circuit's efficiency through post-layout simulations and experimental results.

Main Methods:

• Designed an Active Quenching-Active Reset (AQAR) circuit utilizing body biasing.
• Implemented the circuit in a 28 nm Fully Depleted Silicon On Insulator (FD-SOI) CMOS process.
• Performed post-layout simulations and experimental measurements to verify performance.

Main Results:

• The AQAR circuit achieves avalanche detection in under 40 picoseconds.
• Demonstrated a reduction in avalanche charge by up to 50%.
• Achieved a reduction in afterpulsing by up to 50% compared to conventional methods.

Conclusions:

• The ultrafast AQAR circuit effectively mitigates afterpulsing in SPADs.
• Body biasing is a key technique for rapid avalanche detection and quenching.
• The proposed circuit offers significant performance improvements for SPAD applications.