Optical activity and phase transformations in γ/β Ga2O3 bilayers under annealing

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Azarov, Alexander, Galeckas, Augustinas, Cora, Ildikó, Fogarassy, Zsolt, Venkatachalapathy, Vishnukanthan, Monakhov, Eduard, Kuznetsov, Andrej
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913615002468352
author Azarov, Alexander
Galeckas, Augustinas
Cora, Ildikó
Fogarassy, Zsolt
Venkatachalapathy, Vishnukanthan
Monakhov, Eduard
Kuznetsov, Andrej
author_facet Azarov, Alexander
Galeckas, Augustinas
Cora, Ildikó
Fogarassy, Zsolt
Venkatachalapathy, Vishnukanthan
Monakhov, Eduard
Kuznetsov, Andrej
contents Gallium oxide (Ga2O3) can be crystallized in several polymorphs exhibiting different physical properties. In this work, polymorphic structures consisting of the cubic defective spinel (gamma) film on the top of the monoclinic (beta) substrate were fabricated by disorder-induced ordering, known to be a practical way to stack these polymorphs together. Such bilayer structures were annealed to investigate the optical properties and phase transformations. Specifically, photoluminescence and diffuse reflectance spectroscopies were combined with transmission electron microscopy, Rutherford backscattering/channeling spectrometry and x-ray diffraction to monitor the evolutions. As a result we observe a two-stage annealing kinetics in gamma/beta Ga2O3 bilayers associated with the epitaxial gamma-to-beta regrowth at the interface at temperatures below 700 °C and a non-planar gamma-to-beta phase transformation starting at higher temperatures. Thus, the present data enhance understanding of the polymorphism in Ga2O3, interconnecting the phase transformation kinetics with the evolution of the optical properties.
format Preprint
id arxiv_https___arxiv_org_abs_2405_20011
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Optical activity and phase transformations in γ/β Ga2O3 bilayers under annealing
Azarov, Alexander
Galeckas, Augustinas
Cora, Ildikó
Fogarassy, Zsolt
Venkatachalapathy, Vishnukanthan
Monakhov, Eduard
Kuznetsov, Andrej
Materials Science
Gallium oxide (Ga2O3) can be crystallized in several polymorphs exhibiting different physical properties. In this work, polymorphic structures consisting of the cubic defective spinel (gamma) film on the top of the monoclinic (beta) substrate were fabricated by disorder-induced ordering, known to be a practical way to stack these polymorphs together. Such bilayer structures were annealed to investigate the optical properties and phase transformations. Specifically, photoluminescence and diffuse reflectance spectroscopies were combined with transmission electron microscopy, Rutherford backscattering/channeling spectrometry and x-ray diffraction to monitor the evolutions. As a result we observe a two-stage annealing kinetics in gamma/beta Ga2O3 bilayers associated with the epitaxial gamma-to-beta regrowth at the interface at temperatures below 700 °C and a non-planar gamma-to-beta phase transformation starting at higher temperatures. Thus, the present data enhance understanding of the polymorphism in Ga2O3, interconnecting the phase transformation kinetics with the evolution of the optical properties.
title Optical activity and phase transformations in γ/β Ga2O3 bilayers under annealing
topic Materials Science
url https://arxiv.org/abs/2405.20011