Double-Layered-NiO/ β -Ga 2 O 3 Heterojunction Diode With 2870-V/20-A and 12.80-ns Reverse Recovery Time

This work demonstrates a significant advancement in high-power p-NiO/$\beta $-Ga2O3heterojunction diode (HJD) technology. A large-area ($2\times 2$mm${}^{{2}}\text {)}$HJD is fabricated, achieving a remarkable combination of a 2870-V breakdown voltage (BV) and a 20-A forward current. This performance is enabled by a novel terminal structure incorporating a double-layered p-NiO film. The device exhibits a low specificon-resistance (${R}_{\text {on},\text {sp}}\text {)}$of 14.4 m$\Omega \cdot $cm2, yielding a high Baliga’s power figure of merit (P-FOM) of 572 MW/cm2(calculated as P-FOM = BV2/${R}_{\text {on},\text {sp}}\text {)}$. Furthermore, it displays excellent fast-switching characteristics, with an ultrashort reverse recovery time of 12.80 ns and a low reverse recovery charge of 19.70 nC. The surge current capability is confirmed to be 16 A at a voltage of 11.1 V. Temperature-dependent electrical characterization from 298 to 448 K reveals key insights. The forward current and turn-on voltage decrease linearly with increasing temperature, with a zero-temperature coefficient (ZTC) bias point observed at approximately 2.3 V. The reverse leakage current follows a thermally activated mechanism, as evidenced by a linear relationship between its natural logarithm and the reciprocal of absolute temperature behavior characteristic of a conventional p–n junction. These results underscore the broad prospects of Ga2O3HJDs for next-generation high-voltage and high-power electronic applications.