Implant Dose Sensitivity of 0.1µm CMOS Inverter Delay

The simulation experiment is performed to characterize the impact of process level fluctuations on the circuit performance variation for the 0.1µm CMOS technology. The 0.1µm NMOS and PMOS transistors are optimized using four different ion implantation steps namely super steep retrograde channel (SSRC) implant, deep s/d implant, shallow s/d extension implant and halo implant. We demonstrate that the fluctuations in the nominal values of these implant doses result in the significant variation in DC (Ioff, Ion, Vt) and AC (Cgg) parameters of the transistors. The DC and AC parameter variations of these devices in turn have their effect on the performance of the inverter circuit. In particular, the halo implant has the maximum impact resulting in ∆Ioff=122% (97.48%) and ∆Ion=4.82% (5.29%) for NMOS (PMOS) transistor. The worst case delay variation is more than ±10% for a ±10% random variation in the implant dose parameters.