Variable Body Effect Factor Fully Depleted Silicon-On-Insulator Metal Oxide Semiconductor Field Effect Transistor for Ultra Low-Power Variable-Threshold-Voltage Complementary Metal Oxide Semiconductor Applications

Abstract

We propose the concept of a variable body effect factor Fully Depleted Silicon-On-Insulator Metal Oxide Semiconductor Field Effect Transistor (FD SOI MOSFET) in which the body effect factor is varied by the substrate depletion capacitance. In this device, both higher drive current in the active mode and low leakage current in the standby mode can be obtained in the variable threshold voltage scheme. In the active mode, the body effect factor is reduced by the substrate depletion capacitance and the drive current increases. In the standby mode, the substrate is inverted or accumulated, and the depletion layer capacitance is neglected, resulting in a larger body effect factor that suppresses the standby subthreshold current. We demonstrate the validity of the proposed scheme with two-dimensional simulations and experiments.