High-Speed Graded-Channel GaN HEMTs with Linearity and Efficiency

We report high-speed graded-channel GaN HEMTs with 10 dB OIP3 improvement over current conventional AlGaN/GaN HEMTs at the same DC power. Thus, the graded-channel GaN HEMTs demonstrated a record OIP3/Pdc of 17–20 dB at 30 GHz. Also, these graded-channel GaN HEMTs demonstrated PAE of 75% at 1.2 W/mm output power density. The measured PAE and output power density show great improvement over reported PAE of other mm-wave T-gated AlGaN/GaN HEMT devices.