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Title: Atomic scale mechanism of β to γ phase transformation in gallium oxide
We report the detailed mechanism behind the β to γ phase transformation in Sn-doped and Si-implanted Ga2O3 that we determined based on the direct observation of the atomic scale structure using scanning transmission electron microscopy (STEM). Quantitative analysis of the STEM images revealed that the high concentration of impurity atoms favored the formation of interstitial–divacancy complexes, which then leads to the secondary relaxation that creates additional interstitial atoms and cation vacancies, resulting in a local structure that closely resembles γ-Ga2O3. We explain the mechanism of how the impurity atoms facilitate the transformation, as well as the detailed sequence of the local γ phase transformation. The findings here offer an insight on how the lattice respond to the external stimuli, such as doping and strain, and transform into different structures, which is important for advancing Ga2O3 but also a variety of low symmetry crystals and oxides with multiple polymorphs.  more » « less
Award ID(s):
2039380
PAR ID:
10488977
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
Applied Physics Letters
Volume:
122
Issue:
25
ISSN:
0003-6951
Page Range / eLocation ID:
251602
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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