Atomistic simulation of nanowire transistors

作者：Luisier Mathieu; Schenk Andreas^*

来源：Journal of Computational and Theoretical Nanoscience, 2008, 5(6): 1031-1045.

• quantum transport
• tight-binding
• non-equilibrium Green's function
• numerical simulation

At the nanometer scale, the computer simulation of electronic transport cannot be conceived without including quantum-mechanical effects as well as the atomic granularity of the simulation domain. In this review we present a three-dimensional quantum transport simulator based on the Sp(3)d(5)S* semi-empirical tight-binding (TB) method that fulfills these two requirements. The integration of the multi-band TB model into a transport code is only possible, if open boundary conditions (OBCs) are introduced. The available procedures to calculate OBCs in three-dimensional structures are computationally too intensive, since they take the form of a generalized eigenvalue problem or require iterative solvers. Therefore, an improved method based on the scattering-boundary approach is reviewed in this work. It significantly reduces the computational burden associated with the OBCs calculation. Furthermore, it can be formulated either in the Non-Equilibrium Green's Function or in the Wave Function formalism, it works for any channel orientation, material composition, or cross section shape, and it is self-consistently coupled to the three-dimensional computation of the electrostatic potential in the device. These features allow the analysis and the comparison of nanowire field-effect transistors (FETs) with transport along the [100], [110], [111], and [112] crystal axis. Hence, their ON-current, subthreshold swing, and interface roughness sensitivity are investigated.

• 出版日期2008-6