A New Analytical Subthreshold Potential/Current Model for Quadruple-Gate Junctionless MOSFETs

In this paper, we built potential and current models for quadruple-gate junctionless filed-effect transistor (QGJLFET) in subthreshold regime. A new potential distribution function is provided for the cross section of QGJLFETs, based on which we derived a more accurate expression of natural length for QGJLFETs. The result shows that a quadruple-gate FET is far more than a simple composition of two double-gate FETs, but with some coupling components. To avoid complex computation of potential near the corner, we come up with a new concept of equivalent insulator thickness, transforming the influence of corner into the change of insulator thickness. With these renewed parameters and scaling equation, the potential distribution in channel is finally obtained. Based on this potential model, subthreshold current is derived using drift-diffusion approach and Pao-Sah integral.