# Auger Electron Spectroscopy for Chemical Analysis of Passivated (Al,Ga)N-Based Systems

## TL;DR

This paper reviews how Auger Electron Spectroscopy is used to analyze chemical properties of passivated (Al,Ga)N-based systems in electronic devices and sensors.

## Contribution

The paper introduces a detailed AES depth profiling approach to distinguish interfacial from bulk properties in multilayer semiconductor systems.

## Key findings

- AES provides micro- to nanometer-scale chemical information at dielectric/semiconductor interfaces.
- AES identifies chemical states and oxidation transformations in (Al,Ga)N-based systems.
- Optimized experimental conditions reduce sputter-induced artifacts in AES analysis.

## Abstract

This review summarizes the use of Auger Electron Spectroscopy (AES) for microchemical analysis of two different types of dielectric/(Al,Ga)N-based systems: (i) extrinsic dielectric PECVD SiO2, ALD Al2O3, and ECR-CVD SiNx films on AlxGa1−xN/GaN structures in the context of their application in microelectronic power devices and (ii) intrinsic Al2O3 films on AlN epitaxial layers grown by high-temperature oxidation for nanostructured technology of various gas/ion sensors. Particular attention is given to AES depth profiling across complete multilayer cross-sections, combining qualitative analysis of spectral line shape and intensity evolution as well as kinetic energy shifts with quantitative elemental depth distributions. This approach enables identification of chemical states and oxidation-related transformations at dielectric/semiconductor interfaces. Reported results demonstrate that AES provides micro- to nanometer-scale chemical information essential for distinguishing interfacial from the bulk properties. The capabilities and inherent limitations of AES depth profiling, including sputter-induced artifacts are also addressed, highlighting the role of optimized experimental conditions in reliable interface analysis.