Dear Colleagues,

Beta gallium oxide (β-Ga₂O₃) is an exciting wide-bandgap semiconductor with tremendous potential across various technological applications. Its unique properties make it highly suitable for power electronics, solar-blind UV detectors, sensor applications (such as explosives detection), and even as substrates for laser diodes. This Special Issue focuses on the growth aspects of β-Ga₂O₃, including bulk crystals, thin films as well as epitaxial layers with suitable processes. Melt growth techniques Czochralski, Bridgman, floating zone, edge-defined film-fed growth, and Veneuil can be used for bulk crystal growth. Many thin film preparation methods like pulsed laser deposition, spin coating, sputtering, e-beam evaporation, and sol–gel synthesis have been successfully reported. Epitaxial processes, including MOVPE, MBE, and Mist-CVD, have also shown promising results in the literature. The growth of beta gallium oxide (bulk, thin films, epitaxy) encounters many technological challenges and needs significant attention to be addressed for scientific or technical investigations in detail.

Moreover, the Special Issue aims to delve into optimizing the physical properties of β-Ga2O3 for diverse applications. This encompasses comprehensive investigations into the structural, optical, electrical, and spectroscopic properties of both pure and doped β-Ga₂O₃ materials. Understanding these properties is crucial for tailoring β-Ga₂O₃ to specific device structures and maximizing performance.

The scope of this Special Issue extends beyond conventional research boundaries, offering a platform to explore emerging trends in the growth of β-Ga₂O₃ and its physical properties. It encourages the submission of experimental studies, theoretical investigations, and innovative approaches that shed light on the fundamental principles underlying the growth processes and highlight the unique characteristics of β-Ga₂O₃. By bringing together cutting-edge research, this Special Issue aims to propel the field forward and inspire further advancements in the realm of β-Ga₂O₃-based technologies. The potential topics of interest include but are not limited to:

• Experimental aspects of β-Ga₂O₃ Bulk crystal growth;
• β-Ga₂O₃ thin film growth;
• Epitaxial growth of β-Ga₂O₃;
• Material and physical properties of β-Ga₂O₃ (bulk, thin film, epitaxy);
• Structural, optical, electrical, and spectroscopic properties of pure and doped β-Ga₂O₃;
• Device structures and role of physical properties of β-Ga₂O₃ (bulk, thin films, epitaxy).

Dr. Sridharan Moorthy Babu
Prof. Dr. Fan Ren
Guest Editors

Manuscript Submission Information

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• β-Ga₂O₃
• bulk crystal growth
• thin film growth
• epitaxy growth
• physical, structural, optical, electrical, spectroscopic properties
• wide-bandgap semiconductor
• power electronics
• solar-blind UV detectors
• sensor applications
• melt growth techniques
• Czochralski method
• Bridgman method
• floating zone method
• edge-defined film-fed growth method
• Veneuil method

Title: Hydrogen Plasma Influence on Electrical Properties and Deep Traps Spectra of Various Polymorphs of Ga2O3
Authors: A.Y. Polyakov 1; E.B. Yakimov 1,2; V.I. Nikolaev 1,3,4; A.I. Pechnikov 1,3,4; A.V. Miakonkikh 5; A.Kuznetsov 6; A.Azarov 6; In-Hwan Lee 7; A.A.Vasilev 1; A.I. Kochkova 1; I.V. Shchemerov 1; S.J. Pearton 8
Affiliation: 1 National University of Science and Technology MISiS, Moscow, Leninsky pr. 4, Moscow 119049, Russia, Email: aypolyakov@gmail.com 2 Institute of Microelectronics Technology and High Purity Materials, Russian Academy of Sciences, 6 Academician Ossipyan str., Chernogolovka, Moscow Region 142432, Russia 3 Perfect Crystals LLC, 38k1 Toreza Avenue, off.213, Saint Petersburg, 194223, Russia 4 Ioffe Institute, 26 Politekhnicheskaya, Saint Petersburg, 194021, Russia 5 Valiev Institute of Physics and Technology, Russian Academy of Sciences (Valiev IPT RAS), Moscow, 117218, Nahimovsky Ave, 36(1), Russia 6Department of Physics/ Centre for Materials Science and Nanotechnology, University of Oslo, Problemveien 7, 0315 Oslo, Norway 7 Department of Materials Science and Engineering, Korea University, Anamro 145, Seoul 02841, Republic of Korea 8 Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, USA

Title: Orientation Dependence of thermal properties of bulk Ga2O3
Authors: Stephen J. Pearton
Affiliation: Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32606 USA