Physically Based Analytical Modeling of 2D Electrostatic Potential for Symmetric and Asymmetric Double Gate Junctionless Field Effect Transistors in Subthreshold Region

Abstract

In this paper, we propose an analytical 2D model to calculate the potential in the channel for all types of double gate junctionless field effect transistors (DG JLFETs), which is valid in the subthreshold regime. Model is derived by solving 2D Poisson’s equation along the channel while assuming a cubic potential distribution across the silicon thickness. Threshold voltages of different structures are obtained from the proposed potential model. A comparison of subthreshold behavior i.e. threshold voltage roll-off (TVRO) and drain-induced barrier lowering (DIBL) has been made between symmetric and asymmetric DG JLFETs. The effect of bottom gate flat band voltage of asymmetric structures and bottom gate voltage of dissimilar gate biased structures on the threshold voltage are also investigated.