Evaluation of piezoresistace coefficients of silico first-priciples band structures

We have simulated piezoresistance coefficients in single-crystal hydrogen-terminated silicon nanosheets with (001) surface orientation on the basis of first-principles calculations of model structures. The [110] uniaxial tensile stress causes band deformation, and a drastic change of conductivity can be observed for nanosheet models. We have obtained high piezoresistance coefficients for p-type nanosheet of about 1 nm thickness, ¿
_l[110]
= 174 × 10
^-11
Pa
^-1
, and ¿
_t[110]
= -139 × 10
^-11
Pa
^-1
. It is expected that p-type ultra-thin Si(001) nanosheet will be a suitable candidates for nanoscale piezoresistors due to its giant piezoresistivity.