[TuB4] High-Speed III-V Transistors

6:15 PM - 6:30 PM JST(9:15 AM - 9:30 AM UTC)

[TuB4-06] AlN-buffer based AlGaN/GaN HEMTs on free-standing AlN and SiC Substrates for RF Applications

〇Philipp Gribisch¹, Mihaela Wolf¹, Frank Brunner¹, Natalia Kemf¹, Roland Weingärtner², Sven Besendörfer², Oliver Hilt¹ (1. Ferdinand-Braun Institut (FBH) Berlin (Germany), 2. Fraunhofer Institute for Integrated Systems and Device Technology (IISB) Erlangen (Germany))

We present on the fabrication and characterization of AlN-buffer AlGaN/GaN HEMTs on free-standing AlN and SiC substrates for RF applications. The DC and RF performance was evaluated and compared for similar epitaxial layer stacks grown on both substrates. Superior AlN buffer quality was shown for the epitaxy on AlN. The RF output power at 20 GHz of around 3 W/mm is similar for both types of devices. The DC performance and frequency capability lacks behind for the devices on the AlN substrate, which can be related to the difference in gate length and sheet resistance. AlN substrate-based AlN-buffer HEMTs are expected to compete with AlN-on-SiC and compensational doped GaN buffer-based devices for K-band application and beyond when device processing parameters are optimized.