Total Ionizing Dose (TID) Effects
Electronic devices suffer long-term radiation effects, mostly due to
electrons and protons. The main sources of these particles are Solar
Energetic Particle Events - which usually occur in association with solar
flares - and the South Atlantic Anomaly (SAA) - where the Earth's
magnetosphere dips closest to the earth, causing more trapped radiation.
Cumulative long term ionizing damage due to protons and electrons can cause
devices can suffer threshold shifts, increased device leakage
(& power consumption), timing changes, decreased functionality, etc.
Device shielding can help, but several factors must be considered. Shield
geometry & analysis technique, shield material composition, and device
composition are all relevant in predicting shield effectiveness. Electrons
can be effectively attenuated by aluminum shielding even at high energies.
However, while aluminum shielding is effective for low-energy protons, it
is ineffective for the high-energy protons (>30 MeV).
A list of
parts that have been tested for TID since 1991 is available.
Reports are now available on line.
Total Dose Testing is performed at the Goddard Space Flight Center Radiation Effects Facility (GSFC REF).
Dose testing at NASA/GSFC is handled by
Dr. Robert Reed. Please
contact him for further TID information, or contact
Ken Label if you have
a candidate new technology device.
A few useful links:
NASA/GSFC TID Parts
NASA/GSFC Parts Database
Information on electrical, electronic, and electromechanical (EEE) parts for the support of all NASA missions
is available from NASA/GSFC's
EEE Parts Information Management System
EEE Links - a
NASA/GSFC publication concerning parts, packaging, and processes
NASA/JPL RADATA parts data base
REDEX parts data base, compiled by
Naval Research Lab (NRL)
- If you
know of any other relevant links or documents, please let me know!
Return to Radiation Effects & Analysis Home Page
Curator: Martha O'Bryan
Last Revised January 7, 2004
A service of the Radiation Effects and Analysis Group,
Kenneth A. LaBel, Group Leader