Enhanced hot-electron performance of strained Si NMOS over unstrained Si

As the challenges to conventional scaling become more difficult, strained Si/relaxed Si_1-xGe_x structures provide a viable means of improving CMOS performance. For NMOSFETs, the tensile strain in pseudomorphic Si on relaxed Si_1-xGe_x splits the six-fold degeneracy of the conduction band minimum, rendering increased electron mobility due to a lower in-plane effective mass and reduced inter-valley scattering. In this paper, in addition to confirming enhanced performance for strained Si NMOSFETs, we present hot-electron degradation characteristics for the first time, showing improvement over unstrained Si.