Long-range coulomb interactions in small silicon devices: Transconductance and mobility degradation

In small silicon devices, conduction electrons in the channel are subject to long-range Coulomb interactions with electrons in the heavily-doped drain, source, and gate regions. We show that for devices with channel lengths shorter than about 40 nm and oxides thinner than 2.5 nm these interactions cause a reduction of the electron velocity. We present results, obtained using both semiclassical two-dimensional self-consistent Monte Carlo-Poisson simulations and a quantum-mechanical model based on electron scattering from gate-oxide interface plasmons.