Publication Type
Journal
Journal Name
Journal of Applied Physics
Publication Date
Page Number
094108
Volume
100
Issue
9
Abstract
The influence of Hf-based dielectrics on the underlying SiO2 interfacial layer IL in high-k gate
stacks is investigated. An increase in the IL dielectric constant, which correlates to an increase of the
positive fixed charge density in the IL, is found to depend on the starting, pre-high-k deposition
thickness of the IL. Electron energy-loss spectroscopy and electron spin resonance spectra exhibit
signatures of the high-k-induced oxygen deficiency in the IL consistent with the electrical data. It is
concluded that high temperature processing generates oxygen vacancies in the IL responsible for the
observed trend in transistor performance.