Optimization of doping profile and isolation oxide thickness in bulk FinFETs using TCAD simulations

The effect of doping profile of channel stop implant underneath the fin for optimum thickness of isolation oxide corresponding to minimum IOFF, maximum ION and maximum ION/IOFF has been studied in 65nm Bulk FINFET by device simulations in TCAD. Studies are done by varying the peak position of doping concentration and position at which it equals substrate concentration with respect to substrate height for isolation oxide thickness varying from 10–100 nm. Performance metrics used are minimum IOFF, maximum ION and maximum ION/IOFF. The optimized isolation oxide thickness for minimum IOFF, is observed at 10 nm with position of peak doping concentration at minimum alpha and maximum sigma.