Impact of High-Temperature Forward Bias Stress on the Electrical Performance Degradation of β-Ga₂O₃ Schottky Barrier Diodes

This work focuses on the degradation mechanism of vertical Pt/Au beta-gallium oxide (
$\beta $
-Ga2O3) Schottky barrier diodes (SBDs) under high-temperature forward bias (HTFBs) stress. After being exposed to HTFB stress (13 V at 200 ° C) for 10 ks, a remarkable decrease of 60% in on-state current density (
${J}_{\text {on}}\text {)}$
, and a substantial increase of four orders of magnitude in the reverse current density (
${J}_{\text {r}}\text {)}$
are observed through current-voltage (I–
${V}\text {)}$
measurements. Utilizing the capacitance-voltage (C–V) measurements, it is noted that the carrier concentration within the Ga2O3 drift layer is slightly reduced from
$1.9\times 10^{{16}}$
to
$1.6\times 10^{{16}}$
cm−3 after stress. Moreover, based on the results of frequency-dependent conductance technique, the density of Pt/Ga2O3 interface state is found to significantly increase from
$1.51\times 10^{{12}}$
–
$3.42\times 10^{{12}}$
cm
$^{-{2}}\cdot \,$
eV−1 to
$2.65\times 10^{{13}}$
–
$5.96\times 10^{{13}}$
cm
$^{-{2}}\cdot $
eV−1 while the trap activation energy clearly rises from 0.088–0.096 eV to 0.116–0.132 eV following the 10 ks HTFB stress. Comparing the changes in interface states and bulk traps of the device, it is clear that the interface states in Pt/Ga2O3 dominate the deterioration of the
$\beta $
-Ga2O3 SBD under HTFB stress.