With the development of high-voltage switches and high-speed RF circuits, the enhancement mode(E-mode) AlGaN/GaN HEMTs have become a hot topic in those fields. The E-mode GaN-based HEMTs have channel current at the positive gate voltage, greatly expanding the device in low power digital circuit applications. The main methods to realize E-mode AlGaN/GaN HEMT power devices are p-GaN gate technology, recessed gate structure, fluoride ion implantation technology and Cascode structure (Cascode). In this paper, the advantage and main realizable methods of E-mode AlGaN/GaN HEMT are briefly described. The research status and problems of E-mode AlGaN/GaN HEMT devices fabricated by p-GaN gate technology are summarized. The advances of p-GaN gate technology, and focuses on how these research results can improve the power characteristics and reliability of E-mode AlGaN/GaN HEMT by optimizing device structure and improving process technology, are discussed.
Simulation and experimental investigation of recessed-gate AlGaN/GaN HEMT