An Efficient Quantum-Based Model for the Threshold Voltage of Thin Film Double Gate/Silicon on Insulator Silicon Metal Oxide Semiconductor Field Effect Transistors

In this paper, an efficient non-iterative approach for calculating the threshold voltage of nanoscale double gate n-channel metal oxide semiconductor field effect transistor (nMOSFET) is presented. First, it is shown that the parabolic potential is a reasonable approximation for the body potential along the coordinate normal to the interfaces at the threshold of conduction. Then, the eigen functions and eigen values of confined carriers are determined by solving the Schrödinger’s equation using the Wentzel–Kramers–Brillouin (WKB) approximation. All the coefficients of the potential polynomial are obtained analytically at the threshold condition. To assess the accuracy of the proposed model, its predictions have been compared to the results of a numerical simulator and a previously published model. It is observed that the approach can accurately yet efficiently predict the threshold voltage for both symmetric and asymmetric double gate structures as well as fully depleted silicon on insulator (SOI) structures with intrinsic or doped body.