High Threshold Voltage Enhancement-Mode Regrown p-GaN Gate HEMTs With a Robust Forward Time-Dependent Gate Breakdown Stability

In this work, we demonstrate enhancement-mode regrown p-GaN gate devices with high threshold voltage as well as a robust forward time-dependent gate breakdown (TDGB) stability. The regrown p-GaN gate HEMTs are fabricated with two different AlGaN barriers. Devices with 16nm Al0.235 Ga0.765 N yield a
$\text{V}_{\text {TH}}$
of 1.5V and a high threshold voltage (
$\text{V}_{\text {TH}}$
) of 2.7V is observed for 7nm AlGaN along with a gate breakdown voltage of more than 10V. Lastly, the regrown p-GaN gate HEMTs with 7nm AlGaN barrier demonstrate an operating
$\text{V}_{\text {G}}$
of 7.46V and 7V for 1% failure rate of 10-year lifetime at 150°C and 25°C, which is amongst the highest values compared to the reported literature for regrown p-GaN gate HEMTs.