Rf high-electron-mobility transistors including group iii-n stress neutral barrier layers with high breakdown voltages

Abstract

A High Electron Mobility Transistor (HEMT) device can include an AlN buffer layer on a substrate and an epi-GaN channel layer on the AlN buffer layer. An AlN barrier layer can be on the Epi-GaN channel layer to provide a channel region in the epi-GaN channel layer. A GaN drain region can be recessed into the epi-GaN channel layer at a first end of the channel region and a GaN source region can be recessed into the epi-GaN channel layer at a second end of the channel region opposite the first end of the channel region. A gate electrode can include a neck portion with a first width that extends a first distance above the AlN barrier layer between the GaN drain region and the GaN source region to a head portion of the gate electrode having a second width that is greater than the first width.