Determination of uniaxial stress of embedded Si1−yCy source/drain nMOSFETs using numerical simulation techniques

Uniaxial stress induced by recessed or embedded Si
_1-y
C
_y
source/ drain in nanoscale nMOSFETs is computed using finite element method adopted in numerical process simulator. The lateral, vertical and perpendicular stress components S
_xx
, S
_yy
and S
_zz
, respectively, are determined as a function of mole fraction y in the range 0.5 - 2.5 % and channel length L between 22-130 nm. Simulation results show that S
_xx
in the middle of the channel at a distance 0.35 nm below the oxide semiconductor interface decreases linearly with L, while the other components exhibit a stronger nonlinear dependence on length. The implications for further device and process modeling will be addressed in a nutshell.