Interface Trap Density Estimation in FinFETs Using the $ g_{\mathrm{ m}}/ I_{\mathrm{ D}}$ Method in the Subthreshold Regime

In this paper, we show that the subthreshold current-voltage characteristic can be used for estimating the interface trap density as a function of the energy in fully depleted symmetric metal-oxide-semiconductor devices with a minimum amount of modeling. The method is analyzed using TCAD simulations, and illustrated with the measurements on n-type silicon-on-insulator FinFETs. The results indicate that the trap density can be extracted between ~0.65 and 0.90 eV. This range is limited by resolution issues at the lowest current levels, and by the transition from subthreshold to saturation behavior at the high current levels.