Surface-state engineering for interconnects on H-passivated Si(100).

Abstract

Surface-state engineering strategies for atomic-size interconnects on H-passivated Si(100) surfaces are explored. The well-known simple interconnect formed by removing H-atoms from one of the Si atoms per dimer of a dimer row along the Si(100) surface is poorly conducting. This is because one-dimensional-like instabilities open electronic gaps. Here, we explore two strategies to reduce the instabilities: spacing the dangling bonds with H atoms and changing the geometry by increasing the lateral size of the wires. The resulting wires are evaluated using density functional theory. Surprisingly, zigzag dangling-bond wires attain atomically confined conduction properties comparable with the conduction of free-standing metallic monatomic wires. These results hint at band-engineering strategies for the development of electronically driven nanocircuits.