High speed and high photosensitivity wide dynamic range photodetectors for CCD image sensor arrays

Linear CCD image sensors that achieve high speed and high photosensitivity over a wide dynamic range of light intensities are useful in applications such as laser beam profiling, acousto-optic signal processing and welding. Although present day detector technology is capable of achieving high speed and photosensitivity, few technologies have the added capability of wide dynamic range (WDR). This thesis is about the development of detectors capable of achieving these three critical specifications simultaneously.; Wide dynamic range can be achieved using two different techniques: exploitation of subthreshold current flow over a barrier and signal charge partitioning based on collection well areas. New detectors, conceived and developed by the author, that use a hybrid of these techniques including a floating gate implementation are presented. In addition, a new third technique called 'switched CCD electrode compression' is introduced. The development of these photodetectors including evaluation of fabricated devices is presented where dynamic ranges in excess of 5 orders are achieved. The barrier type photodetectors including a floating gate device, are analyzed using a non-conventional approach of examining non-ideality factors.; As background, the thesis discusses present state of the art photodetectors including the Chamberlain source-gate connected wide dynamic range photodetector. Three different types of CCD image sensor architectures that can be used with the new detectors are reviewed.