Translator Disclaimer
17 September 2007 Radiation effects in two InGaAs focal plane arrays
Author Affiliations +
As part of the early development for NASA's Mars Laser Communication Demonstration (now canceled), we exposed two InGaAs focal plane arrays (FPAs) to 22 krad(Si) dose at a rate of 4.6 rad(Si)/s using a 60Co gamma-ray source. Both the SU320MS from Sensors Unlimited and the ISC9809 from FLIR Systems, Inc. operated throughout the test. The FPA electronics were shielded from radiation; only the photosensitive InGaAs and its readout integrated circuit (ROIC) were exposed. Background levels on both FPAs increased during the test. The SU320MS saturated and failed to respond to infrared light after the test. The ISC9809's background increased but did not saturate. Phenomena exhibited during the test included both isolated single-pixel hits and increased mean over the full FPA. Tests of the ISC9809 after irradiation indicate no change in gain but an increase in mean dark current. In addition, 91% of the ISC9809 pixels also had increased temporal noise. As a result of these tests, the ISC9809 was chosen for flight, but shielding was added to reduce the level seen by the FPA to an estimated 6 krad(Si) for a 10-year lifetime in Mars orbit.
© (2007) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Frederick Knight, Matthew Waldon, Brian Greensmith, Michael Mattei, Lado Tonia, and Nicholas Gould "Radiation effects in two InGaAs focal plane arrays", Proc. SPIE 6690, Focal Plane Arrays for Space Telescopes III, 66900E (17 September 2007);

Back to Top