Comparison of Total Ionizing Dose Effects in 16-nm Core and I/O n-FinFETs

Total ionizing dose (TID) response of 16-nm core and input-output (I/O) n-type fin field-effect transistors (n-FinFETs) with various gate lengths and fin numbers are investigated in this study. The TID sensitivity of I/O n-FinFETs is much higher than that of core devices. The reverse breakdown voltage measurement of drain-bulk junction indicates that I/O n-FinFETs have a lower doping concentration in the channel stop region compared with core devices. The low doping concentration is considered as the root cause of the high TID sensitivity of I/O n-FinFETs. Technology computer-aided design (TCAD) simulation is used to analyze the influence of ion implantation process on doping distribution of the channel stop region, as well as the TID response under different ion implantation process conditions. Known from the simulation, when increasing the doping concentration in upper area of channel stop by adjusting the ion implantation parameters, the TID damage can be effectively suppressed.