Radiation Failure Modes in CMOS Integrated Circuits

The radiation sensitivity of commercial and laboratory CMOS processes has been investigated. Failure levels for CMOS circuits have been related to transistor threshold voltage shifts and typical inverter failure modes. CMOS inverter characteristics have been measured as a function of the ionizing radiation exposure for devices fabricated by 10 different manufacturers and representing a total of 15 different processes. By selecting certain processes, CMOS circuits can be obtained which will operate after exposure to an ionizing radiation dose greater than 106 rads (Si).