Valence-band offset in ultra-thin HfO<inf>2</inf> film on Si<inf>1&#x2212;x</inf>Ge<inf>x</inf>/Si substrate

Abstract

This paper presents the first-principles study of an ultra-thin HfO 2 on SiGe/Si substrate. The strong stress in hafnia layer caused by lattice mismatch significantly deforms the structure in this layer, and alters the valence-band offset between HfO 2 and SiGe. These phenomena should significantly affect the properties of CMOS devices associated with an ultra-thin HfO 2 dielectric film.