Long-Term Radiation Transients in GaAs FETs

Abstract

A long-term transient response mechanism has been discovered in certain GaAs FETs and FET logic circuits exposed to low level (~ 100 rad) ionizing radiation pulses. Recovery times ranging from 1 to 70 seconds have been measured following room temperature exposures. Charge trapping within the semiinsulating GaAs substrate appears to be a mechanism responsible for the observed behavior. Experiments conducted between 0° and 200°C have identified an acceptor level characterized by an activation energy in the 0.7 to 0.8 eV range.