Transport mechanism investigation of β-Ga₂O₃ based fin-shape heterojunction PN diodes

Abstract This paper proposes a new type of Fin-shape Ga 2 O 3 heterojunction PN diode (Fin-PND), it not only maintains a high breakdown voltage, but also increases the current density, thereby reducing the on-resistance. The conventional Schottky barrier diode (SBD) and PN diode (PND) are also prepared for comparison. The I-V characteristics, breakdown characteristics, and temperature stability of these three devices have been studied. It has been found that the Fin-PND has a lower turn-on voltage of 2.05 V due to the lower N D caused by Cl-based etching. Furthermore, the Fin-PND has a higher current density of 692.1 A cm −2 and specific on-resistance (R on,sp ) of 7.31 mΩ·cm 2 compared to the conventional PND. In addition, the breakdown voltage of the Fin-PND is similar to that of the PND and higher than that of the SBD, reaching a value of 2380 V. The Fin-PND overcomes the contradiction of the current density rising at the expense of the breakdown voltage. Moreover, under the same variable temperature test conditions, the Fin-PND shows more favorable temperature stability.