Atomistic modeling of semiconductor interfaces

A strong contributing factor to the success of silicon has been a parallel development of accurate modeling tools. For the efficient introduction of new device architectures at the nanoscale, it is necessary to develop similar tools that can handle all the relevant aspects of the new physical properties that will be utilized. This is a very challenging task, as we are dealing not only with many new materials and even more combinations of elements materials, but also effects due the small device sizes and even reduced dimensionality in the form of confinement. In this article we turn our attention to the topic of simulating interfaces from first principles, on the atomic scale. As device dimensions shrink, interfaces start to play a dominating role, and need to be treated as an active part of the device, and not just as an invisible boundary between different materials. We will review the theoretical framework for computing properties of single interfaces, and provide several examples of the types of simulations that can be performed. A concluding separate section is dedicated to computing band offsets.