16-band single-photon imaging sensor based on Fabry-Perot resonance

Area of Science:

• Optoelectronics
• Nanotechnology
• Spectroscopy

Background:

• Fabry-Perot (FP) etalons are crucial for spectral filtering.
• Near-infrared (NIR) imaging requires high-resolution spectral selectivity.
• Integrating filters with single-photon detectors presents unique challenges.

Purpose of the Study:

• To design and fabricate a 16-wavelength selective spectral bands imaging sensor.
• To achieve wavelength selectivity and tunability in the NIR band (715 nm-915 nm).
• To combine an ultra-narrow band FP filter with a single photon avalanche diode (SPAD) for the first time.

Main Methods:

• Fabrication of a Fabry-Perot structure using SiC/SiO2 distributed Bragg reflector (DBR) multilayers.
• Tuning the SiO2 interval layer thickness for wavelength selectivity.
• Integration of the FP filter with a SPAD and development of a reconstruction algorithm.

Main Results:

• Demonstration of a 16 wavelength selective spectral bands imaging sensor.
• High resolution and good uniformity achieved in fabricated FP structures.
• Successful combination of FP filter with SPAD, with an algorithm to mitigate cross-talk.

Conclusions:

• The developed FP spectral imaging sensor offers high performance in the NIR band.
• The integration of FP filters with SPADs is a novel advancement.
• This technology enables new applications in hyper-spectral imaging.