Direct Probing of Trap Dynamics in β-Ga₂O₃ Schottky Barrier Diodes Using Single-Voltage-Pulse Characterization

Gallium oxide (β-Ga₂O₃) is a promising ultrawide-bandgap semiconductor for next-generation power electronics, but its performance is strongly limited by trap states that capture carriers. In this study, a single-pulse characterization method is presented to directly probe trap dynamics in β-Ga₂O₃ Schottky barrier diodes (SBDs). Transient current responses are systematically investigated under varying pulse widths, rise and fall times, amplitudes, and temperatures. The results reveal that traps in the neutral region progressively participate in electron capture, resulting in current decay during the constant-voltage phase. Additionally, a delayed trap response produces asymmetry between the ramp-up and ramp-down transients. Analysis of the current decay yielded a trap density of ≈5×10¹⁴ cm^-2, representing the total trap density near the Schottky junction. Exponential fitting provides a carrier capture time constant of ≈ 30 µs at a forward bias of 2 V, consistent with the onset of trap-induced current degradation. Temperature-dependent measurements indicate that carrier capture is suppressed at elevated temperatures, resulting in a trap activation energy of ≈0.16 eV. These findings demonstrate that the single-pulse method offers a straightforward and effective approach for evaluating trap states under practical operating conditions in β-Ga₂O₃ devices.