Patent attributes
The presented readout structure provides charge transport based readout of a photosensitive device with a minimum number of transport gates. The structure uses the given charge storage buckets of the photosensitive device, separated by a minimum sized barrier-gate, to transport the charge out of the pixel field. This new readout schema allows for a fast readout speed based on a 2 phase transport chain and increases the pixel's optical fill factor by significantly reducing the transport gate size compared to state-of-the-art pixels using a 3 or 4 phase CCD readout chain. This readout structure can be exploited for standard photo-detecting elements such as e.g. pinned photo-diodes or any enhanced pixel structure that has additional intelligence incorporated as well. Typical applications are 2D- or 3D-imaging. The process used for manufacturing a sensor with such a readout scheme requires preferably charge transport mechanisms like charge-coupled gate devices as well as the possibility of integrating circuitries of high density. The exploitation of such a combination of process-related features results in a new sensor readout technique that allows for optimizing the pixel's dynamic range and optical fill factor.
