Effects of Quantum Confinement on Charge-Based Threshold Voltage Definition

A threshold voltage definition for MOS diodes that uses $2\psi_{B}$ surface-to-substrate band bending as the threshold criterion is widely accepted in spite of some inherent weaknesses. Recently, a new MOS diode threshold voltage definition was proposed based on a standardized log-linear charge vs. voltage relationship to overcome shortcomings of the $2\psi_{B}$ definition. In this presentation, effects of quantum confinement on the new definition are analyzed in detail. It is shown that a constant quantum correction on gate oxide thickness will suffice for the new definition to work properly.