Operating-Condition Optimization of MG-MOSFETs for Low-Voltage Application

Adaptive threshold-voltage controlling of thin-film multi-gate (MG) MOSFETs, using independent back-gate biasing, is applied for realizing latency and power optimization. The controlling-method validity for low-voltage operation is analyzed with the compact model HiSIM-MG, considering all internally induced charges and specific short-channel effects due to MG controlling. Current-drivability degradation due to back-gate charge and existence of an optimized operating condition are confirmed. Circuit-performance improvement of 27% by about 30% reduction of substrate thickness, while keeping switching-power loss small, is verified.