Investigation of electron and hole mobilities in MOSFETs with TiN/HfO/sub 2//SiO/sub 2/ gate stack

Abstract

In this work, the effective mobility of HfO/sub 2/ nMOSFETs and pMOSFETs has been investigated using low temperature measurements and constant voltage stress. It was found that the Coulomb scattering mechanism has significant influence on mobility degradation. A correlation between trapped charge and mobility degradation has been made, that could explain the difference observed in nMOS and pMOS mobility behavior compared to SiO/sub 2/.