Understanding of mobility degradation induced by gate charges of Ge pMOSFET

Hole mobility degradation due to the Coulomb scattering from the Geox/Al2O3 gate stack of Ge pMOSFET is investigated. There are fixed charges at the Ge/GeOxand Geox/Al2O3 interfaces and dipole at the Geox/Al2O3 interface. These charges can be changed by N2 and O2 PDA. The hole mobility is mainly affected by the Ge/GeOx interface charges and Geox/Al2O3 interface dipole.