Local properties at interfaces in nanodielectrics: An ab initio computational study

First-principles computational methodologies are presented to study the impact of surfaces and interfaces on the dielectric and electronic properties of emerging technologically important systems over length scales of the order of inter-atomic distances. The variation of dielectric constant across Si-SiO₂, Si-HfO₂ and SiO₂-polymer interfaces has been correlated to interfacial chemical bonding environments, using the theory of the local dielectric permittivity. The local electronic structure variation across Si-HfO₂ and SiO₂-polymer interfaces, including band bending, band offsets and the creation of interfacial trap states have been investigated using a layer-decomposed density of states analysis. These computational methods form the groundwork for a more thorough analysis of the impact of surfaces, interfaces, and atomic level defects on dielectric and electronic properties of a wide variety of nano-structured systems.