Polarization dependent interface properties of ferroelectric Schottky barriers studied by soft X-ray absorption spectroscopy

TL;DR

This study uses soft X-ray absorption spectroscopy to explore how ferroelectric polarization affects the electronic properties of Schottky barriers at metal-insulator interfaces, revealing polarization-dependent interface behaviors.

Contribution

It introduces a novel application of soft X-ray absorption spectroscopy to analyze polarization-dependent interface properties in ferroelectric Schottky barriers.

Findings

X-ray absorption spectra depend on polarization state.

Photoelectric effects influence the spectra.

Method enables investigation of buried interfaces.

Abstract

We applied soft X-ray absorption spectroscopy to study the Ti L-edge in ferroelectric capacitors using a modified total electron yield method. The inner photo currents and the X-ray absorption spectra were polarization state dependent. The results are explained on the basis of photo electric effects and the inner potential in the ferroelectric capacitors as a result of back-to-back Schottky barriers superimposed by the potential due to the depolarization field. In general, the presented method offers the opportunity to investigate the electronic structure of buried metal-insulator and metal-semiconductor interfaces in thin film devices. Corresponding author: h.h.kohlstedt@fz-juelich.de