Gated Diode Design to Mitigate Radiation Damage in X-Ray Imagers

Radiation damage of amorphous silicon X-ray imagers leads to degradation of the detector´s performance due to increased diode perimeter leakage. To reduce the effect of this damage, a novel pixel device based on a gated diode was fabricated. The additional gate metalization placed on the perimeter of the diode modulates the surface side-wall leakage and has been tested up to a 64 kGy absorbed dose in the diode. This new pixel design significantly reduces the increase in diode leakage and noise due to radiation damage, providing a more uniform performance and extending the lifetime of the imager.