IWGO 2024 Workshop: Recap

From 26th to 31st May, the International Workshop on Gallium Oxide and Related Materials (IWGO 2024) took place at the spectacular Palais am Kulturbrauerei in Berlin. The fifth chapter of the premier international forum was organized by GraFOx — the Berlin-based research network managed by PDI and the Leibniz-Institut für Kristallzüchtung (IKZ) — which focuses on the creation and exploration of oxide systems for new generations of electronic devices.

The co-chairs of the conference were PDI's Oliver Bierwagen and Martin Albrecht from IKZ.

The Program

Over the course of 6 days, 219 participants from 24 countries attended IWGO 2024, including 147 general participants and 72 students, alongside 9 exhibitors and 8 sponsors from Japan, Germany, China, Korea, the United States, and Finland. The packed program ranged in topic from processing to theory/modelling, including characterization, polymorphism, bulk growth, and devices, and featured three keynote lectures, 19 invited talks, 65 contributed talks, a rump session, and more than 150 posters in three poster sessions. This 5th chapter of the IWGO workshop saw a significant increase in submissions compared to previous years, with a total of 241 submitted abstracts. 

Keynote lectures were delivered by Andreas Popp from the Institute for Crystal Growth (IKZ), Germany; Masataka Higashiwaki from the Osaka Metropolitan University and National Institute of Information and Communications Tech, Japan; and Chris G. Van de Walle from the University of California, USA.

Invited talks included:

• Elaheh Ahmadi, University of California, USA: “Hybrid MBE for epitaxial growth of Si-doped ((Al)Ga)₂O₃ films”
• Wenshan Chen, Paul Drude-Institut für Festkörperelektronik (PDI), Germany: “Cation incorporation and reaction kinetics for the MBE growth and Ge-based etching of (SnxGe1-x)O2 for 0 ≤ x ≤ 1”
• Esmat Farzana, Iowa State University, USA: “Vertical β-Ga₂O₃ Diodes for High-voltage and Extreme Radiation Application”
• Roberto Fornari, University of Parma, Italy: “Polymorphism in MOVPE-grown Ga₂O₃: analysis of nucleation and stable growth parameters for the κ phase”
• Zbigniew Galazka, Institute for Crystal Growth (IKZ), Germany: “Bulk rutile-GeO₂ single crystals and wafers with extraordinary physical properties”
• Katie Gann, Cornell University, USA: “Understanding Deactivation of Si Dopants in Implanted β-Ga₂O₃”
• Riena Jinno, University of Tokyo, Japan: “Selective Area Growth of α-Ga₂O₃ on Sapphire Substrates by Mist-CVD and its Thermal Stability”
• Emmanouil Kioupakis, University of Michigan, USA: “Rutile GeO₂ and GeSnO₂ Alloys: A New Family of Ultra-Wide-Band Semiconductors”
• Akito Kuramata, Novel Crystal Technology Inc., Japan: “Recent Status of Ga₂O₃ Crystal Growth Development”
• Yoshinao Kumagai, Tokyo University of Agriculture and Technology, Japan: “Vapor-phase epitaxial growth of gallium oxide using Ga halides as source gases”
• Andrej Kuznetsov, University of Oslo, Norway: “Disorder-induced ordering in gallium oxide polymorphs”
• Matthew D. McCluskey, Washington State University, USA: “Photoluminescence and Raman Mapping of Defects in β-Ga₂O₃”
• Laura Ratcliff, University of Bristol, UK: “Tackling Disorder in γ-Ga₂O₃”
• Darrell Schlom, Cornell University, USA: “Growth of β-Ga₂O₃ and α-(AlxGa1-x)₂O₃ by Suboxide MBE at 1 µm/hr”
• Uttam Singisetti, University of Buffalo, USA: “Electron transport studies in gallium oxide and aluminum-gallium-oxide alloys”
• Kornelius Tetzner, Ferdinand Braun Institute, Germany: “Recent advances in the process development of Gallium Oxide power transistors for high-voltage applications”
• Amanda Wang, University of Michigan, USA: “Mobility in SnO2 and GeO2 from first principles”
• Jiandong Ye, Nanjing University, China: “Enhanced Avalanche in NiO/Ga₂O₃ Herojunction by Edge Termination Optimization”
• Iuliia Zhelezova, University of Helsinki, Finland: “Vacancy defects in Si doped β-(Al,Ga)2O3”

Young Researcher Awards

During the closing remarks, young researchers were recognized for their contribution to the conference. PDI's Wenshan Chen received one of two Wiley Young Researcher Poster Awards for her paper "In-situ etching of Ga, Ge, and In layers in oxide MBE by O₂-induced formation and evaporation of their volatile suboxide". Aditya K Bhat (University of Bristol, UK) received the second award for his paper "Demonstration of a p-Diamond/Ga₂O₃ Heterojunction PN Diode".

Young Researcher Oral Awards were presented to Benjamin M. Janzen (Technische Universität Berlin) for “Comparative Study of Temperature-Dependent Bandgap Transitions in Ga₂O₃ Polymorphs”; Kazuki Koreishi (Tokyo Institute of Technology, Japan) for Characterization of (100) β-(Sc_xGa₁-_x )₂O₃ /β-Ga₂O₃ heterostructures grown by PLD; and Amanda X. Wang (University of Michigan, USA) for “Mobility in SnO₂, GeO₂, and Ge_xSn_1-xO₂ from first principles”.

Beyond the conference

Midway through the conference, delegates enjoyed excursions to the Humboldt Forum and toured through Berlin's underground with Berliner Unterwelten. The conference banquet was held later that evening on the rooftop of Kulturbrauerei with live jazz provided by Sophie Milz Trio.

Acknowledgements

PDI would like to thank all of the organizers of the event, including Roman Engel-Herbert (PDI), Oliver Bierwagen (PDI), Martin Albrecht (IKZ), Henning Riechert (PDI), Markus Wagner (PDI), Kerstin Arnhold (PDI), Eimear Bruen (PDI), Ekaterina Suchilina (PDI), Andreas Wirt-Brunnckow (PDI), and Glen Worthmann (PDI). Special thanks goes to Erika Szegedy (PDI), who, as the Administrative Coordinator of GraFOX, was instrumental in bringing all the moving parts together to make the event a success. 

We also extend our sincere thanks and appreciation to the Technical Program Committee and the International Advisory Committee. The full list of committee members can be found here.

Thanks also go to our sponsors and exhibitors, including platinum sponsors Deutsche Forschungsgemeinschaft (DFG), Novel Crystal Technology Inc., Siltronic, and Taiyo Nippon Sanso. The full list of sponsors and exhibitors can be found here.

Finally, thank you to everyone who supported the event, either by presenting, attending, or volunteering to ensure everything ran smoothly. Your support is much appreciated.

IWGO 2026

As we reflect on the success of IWGO 2024, we are already looking forward to the next chapter in the series, which will be held in 2026. The continued growth and enthusiasm around Ga₂O₃ and related materials underscore the importance of such gatherings, and we are delighted that we could make this contribution to the community in 2024.