Charge injection device camera system for radiation-hardened applications

Abstract

An imaging system for deployment within a high-radiation environment. The imaging system has an imaging array of photosensitive pixels, each of which contains a sense gate for integrating photogenerated charge during the course of a frame and an amplifier transistor for sampling voltage on the sense gate. Each pixel also contains an inject gate and select and reset FETs, for operation as a charge injection device (CID). Moreover, a circuit including a monitor transistor on each polysilicon layer of the imaging array provides a threshold voltage monitor signal used to compensate a drive signal applied to the array on the basis of threshold voltage shifts induced by exposure to radiation. The array is contained within a remote head that may be evacuated and temperature-controlled and that may contain radiation-hardened drive electronics for generating drive signals upon receipt of a start pulse received from a camera control unit located at a significant distance from the remote head.