Enhancement-mode AlGaN/GaN HEMTs with a semi-wraparound metal-insulator-semiconductor gate

In this work, p-GaN gate HEMTs with a semi-wraparound metal-insulator-semiconductor (MIS) gate are investigated. By using SiN and gate metal to surround the p-GaN layer, the output current of the p-GaN gate HEMTs has been increased from 11.4 mA/mm to 15.2 mA/mm, with a high threshold voltage of 8.1 V. The on-state resistance has been reduced from $166.7 m\Omega \cdot mm$ to $97.0 m\Omega \cdot mm$. The peak transconductance error bars show an increase in the average transconductance of the samples from 4.4 mS to 5.5 mS. The breakdown characteristic shows an increase in breakdown voltage from 174 V to 207 V, demonstrating the effectiveness of this method in improving the DC characteristics of p-GaN gate HEMTs.