Investigation of fixed oxide charge and fin profile effects on bulk FinFET device characteristics

Abstract

The effect of positive fixed oxide charge (Q-{\!\!f}) on the electrical characteristics of bulk FinFET devices is investigated and newly addressed as a Fin scaling detractor. The aggressively scaled Fin width leads to abnormal subthreshold slope (SS) degradation in nMOS devices even with a long channel length, while pMOS is free of such degradation. This observation is reproduced and analyzed by a well-calibrated TCAD simulation deck with Q\!\!f introduced. A new Fin profile suppressing the Q\!\!f effect is proposed, and the benefits of the new profile are predicted in terms of variability reduction and mobility improvement, as well as Q\!\!f immunity. © 2013 IEEE.