PhD Thesis Proposal: Nicholas Shade

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Meeting ID: 98787362268
Passcode: 679518

"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 technology have the potential to enable the determination of photon-number, including single photon events, enabling observations at the fundamental limits of physics.

This thesis explores current state-of-the-art detectors and experimentally evaluates three types of next-generation silicon-based detectors that can capture images with high sensitivity and low input-referred read noise, enabling photon counting: 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 photon-number resolution. 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 applicability for space flight missions.

Thesis Committee

• Eric Fossum (Chair)
• Jifeng Liu
• Will Scheideler
• Dr. Shouleh Nikzad (NASA - JPL)

Contact

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