Development of high-power normally-off p-GaN gate AlGaN/GaN high-electron mobility transistors

Normally-off AlGaN/GaN HEMTs with p-GaN-gate, which offer high drain current and low on-state resistance at high threshold voltage and breakdown voltage values above 600V, are particularly attractive for high-power electronics applications. In this work we present the results of development of high power normally-off p-GaN gate AlGaN/GaN high electron mobility transistors carried out at Łukasiewicz Research Network-Institute of Microelectronics and Photonics. We have developed key technological steps i.e. selective etching of p-GaN layers over AlGaN, deposition of proper passivation layer as well as thermally stable isolation of adjacent devices using selective Fe+ ion implantation, which were integrated in the process flow of manufacturing of high power transistors. Finally we have shown measurements of developed normally-off p-GaN gate AlGaN/GaN HEMT power transistors assembled using in-house developed process in TO-220 package.