Radiation-Defect Mitigation Process Restores IR Detector Photoresponse

  • In-situ method quickly restores damaged InAs/GaSb strained-layer-superlattice (SLS) IR detectors
  • Restores detectors to pre-irradiation levels
  • Requires only the voltages and currents of commercial off-the-shelf read-out-integrated-circuits (ROICs)

Abstract
The University of Central Florida invention is a method that cost-effectively restores infrared (IR) image sensors damaged by radiation. The new radiation-defect mitigation technology quickly repairs and prolongs the life of IR sensors, such as long-wavelength IR detectors deployed in near-Earth orbits. Companies can implement the method via software, without affecting the weight or volume of a detector’s electronics. Additionally, the restoration process requires only the voltages and currents of commercial off-the-shelf read-out-integrated-circuits (ROICs) used by the sensor.

Whether exposed to a single burst of radiation (such as gamma rays) or to several smaller doses, an IR detector can suffer damage that significantly degrades its photoresponse capability and performance. With the UCF invention, a detector’s photoresponse can be restored to pre-irradiation levels in seconds and stably maintain it without undue inoperative periods.

Technical Details

The invention encompasses a defect-mitigation strategy for restoring and maintaining the photoresponse of radiation-damaged IR detectors. Essentially, the strategy uses a purely electrical, in-situ radiation-hardening treatment that does not require changes to hardware or any increase in a sensor’s size or weight. The treatment only minimally affects power requirements, as well. Companies can use the strategy on a wide range of detector designs, such as InAs/GaSb Type-II SLS detectors. In one example application of the invention, a GaSb/InAs Type-II SLS sensing circuit receives treatment via software remotely and automatically during the usual dead time between image frames. The process uses only voltages and currents available from standard ROICs for the sensor.

Contact Information

Name: Raju Nagaiah

Email: raju@ucf.edu

Phone: 407.882.0593