Modeling of Tunnelling Currents in Hf-Based Gate Stacks as a Function of Temperature and Extraction of Material Parameters

In this paper, we show that through electrical characterization and detailed quantum simulations of the capacitance-voltage and current-voltage (I-V) characteristics, it is possible to extract a series of material parameters of alternative gate dielectrics. We have focused on HfO2and HfSiXOYNZgate stacks and have extracted information on the nature of localized states in the dielectric responsible for a trap-assisted tunneling (TAT) current component and for the temperature behavior of the I-V characteristics. Simulations are based on a one-dimensional Poisson-Schroumldinger solver capable to provide the pure tunneling current and TAT component. Energy and capture cross section of traps responsible for TAT current have been extracted