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We assess the impact of structural relaxation of defects upon charging on trap-assisted tunneling in high-κ dielectric materials. Zr02/Al203/Zr02 thin films are taken as an exemplary system. In our completely different approach, a first-principles defect model is derived from Hedins GW approximation calculations, which is then coupled to kinetic Monte Carlo charge transport simulations. Comparison between simulation and experiment demonstrates that it is often imperative to take structural relaxation processes into account when modeling nanoscale transport across defect states. [ABSTRACT FROM AUTHOR]

Leakage currents in \TiN/\high-\kappa\-ZrO2/ \TiN capacitors were simulated by using a novel kinetic Monte Carlo algorithm specially designed to describe tunneling transport of charge carriers in high-\kappa dielectrics, including defect-assisted transport mechanisms. Comparing simulation results with experimental data, a model for electronic transport was established and validated. Transport was found to be dominated by Poole–Frenkel emission from positively charged bulk trap states at medium voltages and trap-assisted tunneling at high voltages. Information on the conduction band offset at the \TiN/ZrO2 interface as well as on the trap depth was extracted. The model accurately describes the scaling of the leakage current with temperature and with thickness of the dielectric film, and it provides insight into the mutual interdependence of the competing transport mechanisms. [ABSTRACT FROM AUTHOR]

We report on a simulation algorithm, based on kinetic Monte Carlo techniques, that allows us to investigate transport through high-permittivity dielectrics. In the example of TiN/ZrO2/TiN capacitor structures, using best-estimate physical parameters, we have identified the dominant transport mechanisms. Comparison with experimental data reveals the transport to be dominated by Poole–Frenkel emission from donorlike trap states at low fields and trap-assisted tunneling at high fields. [ABSTRACT FROM AUTHOR]