Effects of a recessed camel-gate head structure on normally-off ALGaN/GaN HEMTs

In this research, a stand-alone camel-gate ({top right corner}) head structure has been studied to investigate the effects of the field plate (FP) in the source access region in AlGaN/GaN high-electron-mobility transistors (HEMTs). The camel gate serves as an FP toward the source side. Using this concept of the camel gate, the transconductance and other forward characteristics have been analyzed with regard to the T-gate. The recessed camel-gate FP scaling is confirmed to enhance the breakdown voltage, transconductance, and output current by reducing the electric field, leakage current, and dispersion in the source access region. Further, the optimized recessed camel-gate AlGaN/GaN HEMT is suitable for use in RF devices because it exhibits a frequency on the order of gigahertz.