Direct Observation of Site-specific Valence Electronic Structure at Interface: SiO2/Si Interface

TL;DR

This study uses soft x-ray spectroscopy to directly observe atom-specific valence electronic structures at the SiO2/Si interface, revealing local electronic variations dependent on chemical states and validated by first-principle calculations.

Contribution

It demonstrates a versatile method for atom-specific electronic structure analysis at interfaces, combining experimental spectroscopy with theoretical calculations.

Findings

Atom-specific valence electronic states were directly observed.

Local electronic structures vary with chemical states.

Experimental results agree quantitatively with first-principle calculations.

Abstract

Atom specific valence electronic structures at interface are elucidated successfully using soft x-ray absorption and emission spectroscopy. In order to demonstrate the versatility of this method, we investigated SiO2/Si interface as a prototype and directly observed valence electronic states projected at the particular atoms of the SiO2/Si interface; local electronic structure strongly depends on the chemical states of each atom. In addition we compared the experimental results with first-principle calculations, which quantitatively revealed the interfacial properties in atomic-scale.