Inactivity Windows in Irradiated CMOS Analog Switches

Radiation tests have shown the existence of inactivity windows in analog switches. It means that the devices lose their ability to switch between ON and OFF states if the total radiation dose is placed between two characteristic values. Once the total radiation dose goes beyond the top value of the window, the switching ability reappears. A physical mechanism based on the evolution of the threshold voltage of irradiated NMOS transistors is proposed in this paper. Finally, consequences of inactivity windows in the conception of radiation tests are discussed