β-Ga₂O₃ in Power Electronics Converters: Opportunities & Challenges

In this work, the possibility of using different generations of <tex-math notation="LaTeX">β</tex-math> -Ga 2 O 3 as an ultra-wide-bandgap power semiconductor device for high power converter applications is explored. The competitiveness of <tex-math notation="LaTeX">β</tex-math> -Ga 2 O 3 for power converters in still not well quantified, for which the major determining factors are the on-state resistance, <tex-math notation="LaTeX">R_ ON</tex-math> , reverse blocking voltage, <tex-math notation="LaTeX">V_ BR</tex-math> , and the thermal resistance, <tex-math notation="LaTeX">R_ th</tex-math> . We have used the best reported device specifications from literature, both in terms of reports of experimental measurements and potential demonstrated by computer-aided designs, to study power converter performance for different device generations. Modular multilevel converter-based voltage source converters are identified as a topology with significant potential to exploit these device characteristics. The performance of MVDC & HVDC converters based on this topology have been analysed, focusing on system level power losses and case temperature rise at the device level. Comparisons of these <tex-math notation="LaTeX">β</tex-math> -Ga 2 O 3 devices are made against contemporary SiC-FET and Si-IGBTs. The results have indicated that although the early <tex-math notation="LaTeX">β</tex-math> -Ga 2 O 3 devices are not competitive to incumbent Si-IGBT and SiC-FET modules, the latest experimental measurements on NiO X / <tex-math notation="LaTeX">β</tex-math> -Ga 2 O 3 and <tex-math notation="LaTeX">β</tex-math> -Ga 2 O 3 /diamond significantly surpass the performance of incumbent modules. Furthermore, parameters derived from semiconductor-level simulations indicate that the <tex-math notation="LaTeX">β</tex-math> -Ga 2 O 3 /diamond in superjunction structures delivers even superior performance in these power converters.