Determination of uniaxial stress of embedded Si_(1-y)C_y source/drain nMOSFETs using numerical simulation techniques

摘要

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.