Total Ionizing Dose Impact on 22-nm FD-SOI Ring Oscillator Current and Frequency

Total ionizing dose (TID) has a significant effect on silicon-on-insulator (SOI) circuits, manifesting primarily as a front-gate threshold voltage (Vt ) shift. This article presents data on ring oscillator (RO) responses of 22-nm fully depleted (FD-SOI) thin oxide (core logic) devices to gamma-ray doses above 1 Mrad(Si). We show large current and frequency TID response differences between ROs comprised of different logic gates. Moreover, the extensive experimental results presented here show that these responses vary significantly with Vt and well type. The measurements show that depending on the expected dose and transistor Vt used, TID-induced standby current (ISB) increases may have a substantial impact on overall power in spaceborne integrated circuits (ICs) using this fabrication process. The TID impact on digital circuit timing margins is also discussed.