(Invited) High-Resolution Photoemission Study of High-k Dielectric Bilayer Stack on Ge(100)

Abstract

Precise determination of energy band alignment of high-k dielectric bilayer stack on Ge(100) has been demonstrated based on the analysis of the photoemission spectra. In the analysis of energy loss signals of O 1s photoelectrons, both elimination of overlapped signals such as Hf 4s and Ge-LMM Auger lines and discrimination of signals from each layer based on photoelectron take-off angle dependence are crucial for accurate determination of energy band gaps. The combination of the analyses of valence band spectra and of energy loss signals of primary core-line(s) taken at different photoelectron take-off angles enables us to determine the energy band offsets and band line-ups of multiple heterojunctions in a non-distractive way.