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=450mA to an off-state with V-R=-200V (dI(F)/dt=16A/s), the peak reverse recovery current (I-rr) and time (t(rr)) was measured to be 19.4mA and 7.1ns, respectively. The amount of charges stored in the drift region and the turn-off energy was extracted to be 0.14nC and 0.054J, respectively. The carrier lifetime under high-level injection conditions in GaN was estimated to be 0.6ns. The reverse recovery characteristics of the GaN diodes showed little sensitivity to elevated temperatures up to 150 degrees C. During the forward recovery (from off-state with V-R=-190V to on-state with I-F=450mA), 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.