摘要
Direct oxidation of composite Al/Ti metal films as gate insulators for AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistors(MOSHEMTs/HEMTs)is successfully realized.The devices fabricated with this novel process exhibit four orders of magnitude reduction in gate leakage current and remarkable breakdown voltage(V br=490 V vs 88 V for normal HEMT)improvement,compared with conventional Schottky-gate HEMTs.Furthermore,the transconductance of the MOSHEMT is only slightly lower(2.6%)than that of Schottky-gate HEMTs and have a wider full width of half maximum.The notable enhancement in device performance renders this new process highly promising for GaN-based microwave power amplifier applications in communication and radar systems.
基金
Supported by the National Natural Science Foundation of China under Grant Nos.60406004 and 60736033
Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices of the Ministry of Education,Microelectronics Institute,Xidian University.
