Transient Radiation Response Mechanisms in Microelectronics

Previous radiation-effect studies on monolithic microcircuits using p-n junction isolation from the substrate showed that failure under pulsed ionizing irradiation occurred because of radiation-induced currents through the substrate junction.1 It was expected, therefore, that removal of the substrate junction would eliminate this failure mode and lead to a less vulnerable circuit. Since additional construction techniques have become available, a study program was initiated to evaluate the relative radiation resistance of each technique. The goal of this program was to develop an understanding of the radiation response of circuits constructed by means of these various techniques. The following material summarizes the important results of this work, the details of which are reported elsewhere.2 The work Is treated in three subjects: 1. Ionizing Radiation Effects 2. Neutron Radiation Effects 3. Latchup