High Threshold Voltage Enhancement-Mode Regrown p-GaN Gate HEMTs With a Robust Forward Time-Dependent Gate Breakdown Stability
Shun‐Wei Tang, Zhen-Hong Huang, Szu-Chia Chen, Wei-Syuan Lin, Brice De Jaeger, D. Wellekens, Matteo Borga, Benoit Bakeroot, Stefaan Decoutere, Tian‐Li Wu
Abstract
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 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{V}_{\text {TH}}$ </tex-math></inline-formula> of 1.5V and a high threshold voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{V}_{\text {TH}}$ </tex-math></inline-formula> ) 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 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{V}_{\text {G}}$ </tex-math></inline-formula> 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.