Investigating the relationship between electron mobility and velocity in deeply scaled NMOS via mechanical stress

The importance of low-field mobility to the performance of deep-sub-100-nm bulk MOSFETs is not well understood. In this work, we investigate experimentally how effective electron mobility at low lateral electric fields relates to velocity in the MOSFET saturation regime, where lateral fields in the channel are high. For short (L-eff approximate to 45 nm) NMOS devices, mobility is modified by externally applying uniaxial stress and the corresponding shifts in electron velocity are found to be significant.