A Review of Vertical Ga2O3 Diodes: From Fabrication to Performance Optimization and Future Outlooks

The demand for compact, high-power electronic devices, such as power trains, and smartphone chargers, continues to grow, driving advancements in power electronics. Traditional silicon-based semiconductors are increasingly unable to meet the performance requirements of these applications due to their physical limitations. As a result, wide bandgap (WBG) materials like silicon carbide and gallium nitride are now widely used for their superior capabilities, although their fabrication remains costly and complex. Recently, gallium oxide (Ga2O3) has emerged as a promising alternative, offering an ultra WBG of 4.8 eV and a breakdown electric field of 8 MV cm(-1) while benefiting from relatively simple and cost-effective growth methods. Despite these advantages, Ga2O3 has limitations, including low electron mobility and poor thermal management, which restrict its use primarily to high-voltage, low-frequency applications such as diodes. This article analyzes recent developments in Ga2O3 diodes, providing an overview of their properties, fabrication techniques, and application-specific performance. The challenges Ga2O3 diodes currently face are examined, particularly in thermal management and electron mobility, and ongoing research efforts aimed at overcoming these issues to enable broader use of Ga2O3 diodes in power electronics are discussed.