Investigation of electron and hole mobilities in MOSFETs with TiN/HfO2/SiO2 gate stack

摘要

In this work, the effective mobility of HfO_2 n and pMOSFETs has been investigated using low temperature measurements and constant voltage stress. It was found that 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_2.