Trapping Investigation of the GaN HEMT Devices Using the Low Frequency Noise Characterization

Abstract

This paper, proposes the characterization of the signature of traps existing in the new AlGaN/GaN HEMT of 0.15 μm ultra-short gate length and 8x50 μm gate width through the output and the input Low Frequency (LF) noise measurement technique. These measurements were performed for varying chuck temperatures (Tchuck) ranging between 25 °C and 125 °C and for the same biasing condition by measuring the output or input noise spectral density. The output drain noise spectral density characteristics demonstrate the existence of an acceptor-like traps. The peak value of those traps shifts towards higher frequencies as the temperature increases. The activation energy Ea around 0.51 eV and the cross section σn around 5x10-15 cm2 were extracted using Arrhenius equation. Furthermore, the input gate noise spectral density characteristics demonstrate the presence of another type of traps. The peak of this traps does not show the frequency shift as the temperature increases. The leakage current measured before and after LF measurements for VGS = -6 V, -7 V and for VDS varying from 0 V to 10 V remains lower than 40 μA/mm.