Large scale computer simulations of strain distribution and electron effective masses in silicon 〈100〉 nanowires

摘要

A multiscale method is proposed to analyze the internal redistribution of tensile strain applied tonsilicon u0003100u0004 nanowires and its effect on electron effective masses mu0001. Nonperiodic, realistic modelsnof unprecedented size containing up to 2.2u0001107 atoms u0001652u000126u000126 nm3u0002 allow the identificationnof nonuniform redistribution patterns specific to the constraints applied to impose external strain.nDepending on how the external strain is imposed, silicon nanowires can show mu0001 behavior similarnto strained bulk silicon, or, as a function of nanowire size, can display intrinsic strain large enoughnthat external strain hardly reduces mu0001 further. For nanowire cross section sizes smaller thann8u00018 nm2 quantum confinement leads to an increase in mu0001 which cannot be compensated for byntensile strain.