| As solid-state image sensors become ubiquitous in sensing, control and photography products, their long-term reliability becomes paramount. This thesis experimentally examines the nature of in-field faults and demonstrates two combined hardware-software approaches for detecting and mitigating them. Characterization experiments found that most tested commercial cameras developed hot pixels that create image bright spots and degrade dynamic range. Faults appear spatially point-like and uniformly distributed, and they develop continually over time. Silicon displacement damage, induced by terrestrial cosmic rays, is the likely cause.;A fault tolerant active pixel sensor is developed to isolate hot defects to a portion of the pixel, enabling software algorithms to correct the faults without sacrificing dynamic range. Experimentally-emulated hot pixels can be corrected within +5% error.;A new statistical software approach is developed to identify and calibrate stuck and abnormal-sensitivity faults from only regular photographs. Monte Carlo simulations verify the detection accuracy in complex environments.;Keywords: image sensor; fault tolerance; hot pixel; active pixel sensor; reliability;Subject Terms: Digital cameras; Imaging systems; Semiconductors--Failures; Semiconductors--Reliability; Integrated circuits--Fault tolerance... |
