Inspection of Trapping and Detrapping Dynamics in Fe- and C-doped GaN-based RF HEMTs by Filling Pulse-Dependent DCT Spectroscopy

The variations in the emission time constant and drain current transient (DCT) amplitude of traps in Fe- and C-doped HEMTs are analyzed at different trap-filling biases and pulse widths. Accordingly, the electron capture and emission dynamics of trap at EC-0.57 eV in the Fe-doped InAlGaN/GaN HEMT are reported. Relatively longer emission time constants (> 100 s at 30 °C) are identified for the trap at EC-0.33 eV in the C-doped AlN/GaN HEMTs.