Switching performance of quasi-vertical GaN-based p-i-n diodes on Si

The switching performance of GaN-based p-i-n diodes on Si was investigated for the first time. A double-pulse test circuit using an inductive load was utilized to evaluate the diode's switching characteristics. When the GaN diode was switched from an on-state with I_F = 450 mA to an off-state with V_R = −200 V (dI_F/dt = 16 A/μs), the peak reverse recovery current (I_rr) and time (t_rr) was measured to be 19.4 mA and 7.1 ns, respectively. The amount of charges stored in the drift region and the turn-off energy was extracted to be 0.14 nC and 0.054 μJ, respectively. The carrier lifetime under high-level injection conditions in GaN was estimated to be 0.6 ns. The reverse recovery characteristics of the GaN diodes showed little sensitivity to elevated temperatures up to 150 °C. During the forward recovery (from off-state with V_R = −190 V to on-state with I_F = 450 mA), the GaN diode exhibited a negligible voltage overshoot. In comparison to a commercial fast recovery-Si diode, the superior reverse and forward recovery performance of GaN-based p-i-n diodes indicates their practicality in fast switching applications and reliability at high temperatures.