Experimental Investigation of Surface-Roughness-Limited Mobility in Uniaxial Strained pMOSFETs

Abstract

This letter provides an experimental assessment of surface-roughness-scattering-limited mobility (mu(SR)) under process-induced uniaxial strain and compares the strain sensitivity between mu(SR) and phonon-scattering-limited mobility (mu(PH)). By an accurate split C-V mobility extraction method, the mu(SR) of short-channel pMOSFETs was extracted at an ultralow temperature to suppress the phonon scattering mechanism. Our result indicates that mu(SR) has stronger stress sensitivity than mu(PH). Furthermore, the surface roughness mobility enhancement tends to increase as the vertical electric field increases. Our experimental findings confirm the previously reported results based on simulations.