Statistical Study of Large-Area Schottky Barrier Diodes Fabricated on 2-in β-Ga2O3 Wafer Using Au-Free Processes

This study reports a statistical study and the fabrication of large-area (3 x 3 mm(2)) Schottky barrier diodes (SBDs) on 2-in beta-Ga2O3 epitaxial wafer, utilizing an industry-compatible and cost-effective gold-free processes. The proposed diode structure integrates implanted edge termination (ET) and low-doped rings (LDRs), which can effectively manage the electric field distribution. The SBDs simultaneously achieved a best-performance breakdown voltage (BV) of exceeding 1300 V and a forward current (I-F) of over 10 A at 2 V, representing a well performance among all reported large-area SBDs with I-F $\ge $ 5 A. Furthermore, the devices exhibited a maximum repetitive BV of over 700 V at I-R = 100 mu A. Additionally, we conducted a statistical performance analysis of the 3 x 3 mm(2) SBDs across the entire wafer. The SBDs have an average repetitive BV of 347 V; 12.5% of the SBDs have a repetitive BV exceeding 650 V, 43.1% fall within the range of 350-650 V, and 44.4% have a repetitive BV below 350 V. Also, we have investigated the causes of variations in the forward and reverse characteristics of devices with the same structure, as well as the relationships between fluctuations in certain physical parameters. This analysis provides valuable insights for future wafer-level processing in industrial applications. This work demonstrates the significant potential of these SBDs for next-generation industrial-grade and low-cost high-power devices.