Valence-band offset in ultra-thin HfO<inf>2</inf> film on GaAs

Abstract

This paper presents the first-principles study of an ultra-thin (monoclinic-) cubic-HfO 2 layer on GaAs substrate. The heavy stress in hafnia layer significantly causes the structure deformation and results in a charge transfer and superstoichiometric HfO y . The valence-band offset of the structure c-HfO 2 /GaAs is increased, while that of m-HfO 2 /GaAs is decreased after structure relaxation. These characteristics should significantly affect the properties of CMOS devices made from an ultra-thin HfO 2 dielectric film stacked on GaAs channel.