Performance Enhancement of ZnGa₂O₄ Metal Oxide-Semiconductor Field-Effect Transistors Grown via Metal Organic Chemical Vapor Deposition on Sapphire Substrates

Wide-bandgap semiconductors have become a central focus in the development of high-performance and energy-efficient electronic devices, particularly metal oxide-semiconductor field-effect transistors (MOSFETs). Therefore, this study specifically delves into the impact of different triethylgallium (TEGa) flow rates during the growth, characterization, and performance evaluation of metal organic chemical vapor deposition-grown wide-bandgap ZnGa2O4 film-based MOSFETs on sapphire substrates. We have observed that the crystallinity of ZnGa2O4 films reached optimal levels at the 30 sccm TEGa flow rate, emphasizing the importance of TEGa flow rates in tailoring the characteristics of films. Based upon the optimized film characteristics, MOSFET devices were fabricated through a conventional photolithography process, incorporating the insights gained from different TEGa flow rates. The electrical performance of these ZnGa2O4 depletion-mode MOSFETs was systematically investigated. The MOSFETs demonstrated a VTH of −12 V, a peak IDS of 210 mA/mm, an impressive IDS on/off ratio of 108, and a sturdy breakdown voltage of 621 V. These remarkable characteristics underscore the nuanced influence of TEGa flow rates on ZnGa2O4 MOSFET performance, particularly in achieving optimal device behavior.