Enhanced Digital Imager Defect Analysis with Smaller Pixel Sizes

Digital imager pixels are shrinking resulting in an increased rate of pixel defects. These defects are known as “Hot Pixels” that are permanent in nature and develop in-field. The number of hot pixels in a given digital imager increases over time. This research experimentally measures defect rates for pixels from 7 μm to those in the cellphone camera range, as low as 1μm. New software algorithms and techniques have been developed to compensate for increasing noise levels in the 2 to 1 μm range. This has allowed the creation of an empirical model that provides accurate projections of defect rates as pixel size decreases and sensitivity increases. Results show that the hot pixel rate increases by 8.9 times as pixels shrink by a factor of 2. Additionally, digital imagers allow us to explore soft errors (known as single event upsets) in a way that can’t be done in traditional ICs.