# Microanalysis of β-(AlxGa1−x)2O3 Films Grown by MOCVD

## TL;DR

This study examines the properties of β-(AlxGa1−x)2O3 films grown using MOCVD, showing how Al content affects optical and structural characteristics.

## Contribution

The study provides new insights into the relationship between Al composition and material properties in β-(AlxGa1−x)2O3 films.

## Key findings

- Al incorporation in the films correlates linearly with the nominal Al composition.
- Optical bandgap increases from 4.96 eV to 5.44 eV with a bowing parameter of 1.7 ± 0.5 eV.
- Higher Al fractions reduce crystallinity and cathodoluminescence intensity while increasing surface roughness.

## Abstract

A combined microanalysis and optical study of β-(AlxGa1−x)2O3 films grown on sapphire via metalorganic chemical vapour deposition, with thickness 350–1000 nm and Al fraction (x) from 0% to 45%, is presented. Al incorporation in the films showed a linear relation with nominal Al composition calculated from precursor flow rate, and the optical bandgap increased from 4.96 eV to 5.44 eV with a bowing parameter of 1.7 ± 0.5 eV. A high Al fraction led to reduced crystallinity, increased surface roughness, and diminished cathodoluminescence intensity. The topography revealed elongated surface features that evolved with Al content, and luminescence spectra exhibited a blueshift in peak emission attributed to the widening of the bandgap. These findings highlight the trade-off between bandgap tuning and material quality, informing future growth strategies for future electronic and optical devices.