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

This letter provides an experimental assessment of surface-roughness-scattering-limited mobility (μ_SR) under process-induced uniaxial strain and compares the strain sensitivity between μ_SR and phonon-scattering-limited mobility (μ_PH). By an accurate split C-V mobility extraction method, the μ_SR of short-channel pMOSFETs was extracted at an ultralow temperature to suppress the phonon scattering mechanism. Our result indicates that μ_SR has stronger stress sensitivity than μ_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.