Analyses on atomic arrangement in dielectric ϵ-Ga2O3 epitaxial thin films

Daichi Oka, Subaru Yusa, Koji Kimura, Artoni Kevin R. Ang, Naohisa Happo, Kouichi Hayashi, Tomoteru Fukumura

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)


Local atomic arrangements of dielectric ϵ-Ga2O3 epitaxial thin films grown on indium doped tin oxide (ITO) and α-Al2O3 substrates were investigated by combining transmission electron microscopy (TEM) and X-ray fluorescence holography (XFH). TEM showed the orthorhombic lattice structure for the ϵ-Ga2O3 thin film on both the substrates and a significant in-plane Ga ion displacement on α-Al2O3. However, XFH revealed a partial disorder of Ga vacancies and a large displacement along the a-axis on ITO. On the other hand, highly ordered Ga vacancies and a displacement of Ga ions toward the Ga vacancy sites were observed for the film on α-Al2O3 by XFH. Such a high degree of freedom in atomic sites and displacements is believed to contribute to a high dielectric constant of ϵ-Ga2O3.

Original languageEnglish
Article number010601
JournalJapanese Journal of Applied Physics
Issue number1
Publication statusPublished - 2020 Jan 1


Dive into the research topics of 'Analyses on atomic arrangement in dielectric ϵ-Ga2O3 epitaxial thin films'. Together they form a unique fingerprint.

Cite this