High Performance Predictable Quantum Efficient Detector Based on Induced-Junction Photodiodes Passivated with...

Area of Science:

• Materials Science and Engineering
• Semiconductor Device Physics
• Optoelectronics

Background:

• Silicon photodetectors are crucial for various optical sensing applications.
• Achieving high quantum efficiency requires minimizing surface recombination and optical losses.
• Dielectric passivation layers like SiO2 and SiNx are essential for silicon device performance.

Purpose of the Study:

• To develop induced-junction silicon photodetectors with record high quantum efficiency.
• To optimize plasma-enhanced chemical vapor deposited (PECVD) SiNx passivation for silicon-dielectric interfaces.
• To minimize recombination and optical losses in silicon photodetectors.

Main Methods:

• Systematic study combining simulation and experimental techniques.
• Optimization of PECVD SiNx deposition parameters.
• Measurements of minority carrier lifetime, fixed charge density, and optical properties.
• 2D and 3D simulations to determine surface recombination velocity and quantum deficiency.
• Fabrication and testing of induced-junction photodiodes using SiO2 and SiNx passivation.

Main Results:

• Optimized PECVD SiNx passivation significantly reduced recombination losses.
• Fabricated photodiodes with SiO2/SiNx stack passivation achieved record high quantum efficiency.
• Predictable Quantum Efficient Detectors (PQEDs) based on these photodiodes showed negligible quantum deficiencies (down to 1 ppm).

Conclusions:

• The developed SiO2/SiNx passivation strategy is highly effective for high-performance silicon photodetectors.
• The optimized photodetectors demonstrate potential for ultra-precise optical measurements.
• This work advances the state-of-the-art in silicon photodetector technology.