Evaluation of TiN/Cu Gate Metal Scheme for AlGaN/GaN High-Electron-Mobility Transistor Application

Abstract

The TiN/Cu metal scheme as gate metal for AlGaN/GaN high-electron-mobility transistors (HEMTs) is investigated. The copper-gated devices show comparable DC characteristics to the conventional Ni/Au-gated devices. No obvious of changes in I-DS and I-GS were observed for the device after being stressed at V-DS = 200 and V-GS = -5 V for 32 h. The thermal stability test indicates comparable Schottky barrier height for the TiN/Cu gate metal on GaN before and after 250 degrees C annealing for 1 h. Overall, the AlGaN/GaN HEMT with the TiN/Cu gate metal structure demonstrates excellent device DC characteristics, good thermal stability, and stable performance after a high-voltage stress test. (c) 2013 The Japan Society of Applied Physics