Coupling atomistic and continuous models for electronic device simulation
Matthias AUF DER MAUR
(Università degli Studi di Roma "Tor Vergata")
Multiscale simulation approaches combining atomistic and continuous media models for the simulation of electronic devices are gaining increasing importance. We present approaches for such coupled simulations which are suitable for electronic transport and optical properties in semiconductor devices. The necessity for multiscale simulations will be discussed, and different coupling schemes introduced. We illustrate how the relevant models describing mechanical strain (linear elasticity, valence force fields), electronic states (k-dot-p, tight-binding) and electronic transport (drift-diffusion, non-equilibrium Green's functions) can be integrated in a multiscale/multiphysics simulation environment. In particular, the interaction between atomistic and continuous media models is described, focusing on a top-down approach where the definition of the atomic structure is based on the macroscopic device description, including the association between atomic structure and finite element mesh and interpolation of physcial quantities. Examples of coupled simulations of III-nitride based quantum well and quantum dot structures, nanocolumns and transistors will demonstrate the main features and critical points of multiscale device simulations.
