Strain Effects on Electronic Bandstructures in Nanoscaled Silicon: From Bulk to Nanowire

In this paper, we present a comparative computational study on strain effects in Si nanostructures including bulk, thin film, and nanowire configurations. We employed a first principles calculation to identify the bandstructure parameters such as band splitting energy and transport effective mass. As a result, we found that bulk Si and Si thin film have similar strain effects on the bandstructure parameters under uniaxial < 110 > strain. Particularly, the effective mass reduction of electrons due to uniaxial < 110 > strain is expected even in Si thin film. On the other hand, Si nanowire structure with nanoscale cross section has lighter transport effective mass than the other structures, regardless of the amount of uniaxial strain.