PhD Thesis Defense: Nicholas Shade

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Meeting ID: 955 6812 9569
Passcode: 592325

"Advancement and characterization of next generation solid-state photon-counting image sensors"

Abstract

Astronomers' pursuit of imaging light from increasingly faint and distant objects in the expanse of space necessitates continuous improvement in signal-to-noise ratio of camera technology. Recent advancements in solid-state detector technologies have enabled the determination of photon-number, including single photon events, enabling observations at the fundamental limits of physics.

This paper presents an evaluation of three next-generation silicon-based detectors capable of photon-counting with deep-sub-electron input-referred read noise: the electron-multiplying charge-coupled device (EMCCD), the single-photon avalanche diode (SPAD), and the CMOS quanta image sensor (QIS). The EMCCD is built using a CCD sensor design that additionally employs repeated impact ionization to amplify the signal during readout, thereby reducing input-referred readout noise to deep-sub-electron levels and facilitating single-photon counting. SPAD devices utilize fast in-pixel signal amplification via impact ionization and positive feedback to achieve negligible effective read noise and precise time-of-arrival measurements of photons, enabling high-precision distance measurement and photon-counting. QIS devices take a distinct approach by utilizing a novel CMOS pixel topology that increases conversion gain without the need for impact ionization, thereby reducing readout noise to deep-sub-electron levels and enabling photon-number resolution, high dynamic range, and high spatial resolution. Characteristics of a representative device from each technology are evaluated with an emphasis on suitability for space flight missions. Furthermore, summary analysis into emerging CCD and CMOS image sensors with “Skipper” readout for photon-number-resolving applications is also discussed in this report.

Thesis Committee

• Eric Fossum (chair)
• Jifeng Liu
• Will Scheideler
• Shouleh Nikzad (NASA-JPL)

Contact

For more information, contact Thayer Registrar at thayer.registrar@dartmouth.edu.