Temperature Sensitivity of Vertical Ga₂O₃ Junction Barrier Schottky Diode Using the p-NiO/n-Ga₂O₃ Heterojunction

A vertical Ga2O3 junction-barrier Schottky (JBS) diode is fabricated using selective p-NiO/n-Ga2O3 heterojunction and applied in temperature sensing. Compared with the Schottky barrier diode (SBD), the JBS device has a higher turn-on voltage and a lower current density. The room-temperature Schottky barrier height and ideality factor are 1.2 eV and 1.2 for the SBD device, whereas they are 1.2 eV and 1.5 for the JBS device, respectively. Therefore, the heterojunction parts of the JBS device contribute to the relatively lower current density. The sensitivities of diodes are obtained from the subthreshold regions of temperature-dependent current-voltage (I–V) curves, which increase with decreased current for both kinds of diodes. However, the sensitivity of JBS under a specific current level is relatively higher than that of SBD even when considering the conduction area. This higher sensitivity is ascribed to the relatively larger ideality factor.