Velocity and mobility investigation in 1-nm-EOT HfSiON on Si (110) and (100)-does the dielectric quality matter?

One of the fundamental questions for gate-stack scaling is whether the low-field mobility measured in long-channel devices is a good proxy for short-channel performance at high field. In this paper, we thoroughly investigate low- and high-field transports (velocity and mobility) in 1-nm-EOT high-κ materials on Si (100) and (110) down to cryogenic temperature. It is shown that scattering in Si substrate dominates the transport at high field, thus enabling relaxation of the low-field-mobility requirement for future scaling below 1-nm EOT.