Effect of Hot Electron Stress on AlGaN/GaN HEMTs of Hydrogen Poisoning

Abstract

We have investigated the effect of hot electron stress on the electrical properties of AlGaN/GaN high electron mobility transistors (HEMTs) of hydrogen poisoning. The AlGaN/GaN HEMTs were biased at the semi-on state, and they suffered from the hot electron stress. The devices of hydrogen poisoning were degraded, while there is almost no degradation for the fresh ones. The hot electron stress leads to the significantly positive shift of threshold voltage and the notable decrease of drain-to-source current for the AlGaN/GaN HEMTs of hydrogen poisoning. For the AlGaN/GaN HEMTs of hydrogen poisoning, the trap density increases by about one order of magnitude after the hot electron stress experiment. The physical mechanism can be attributed to electrically active traps due to the dehydrogenation of passivated point defects at AlGaN surface, AlGaN barrier layer, and heterostructure interface. The results of this paper may be useful in the design and application of AlGaN/GaN HEMTs. INDEX TERMS GaN HEMT, hydrogen poisoning, hot electron stress.

Analysis of Trap and Recovery Characteristics Based on Low-Frequency Noise for E-Mode GaN HEMTs Under Electrostatic Discharge Stress

“…LFN measurements were proven to be an efficient tool to characterize the defects and the density of interface states existing in microelectronic devices, are widely used for reliability assessment of technologies [23,24]. Signatures of the current or voltage spectral densities bring information about the crystal purity (1/f noise source) of the devices [25].…”

Analysis of trap and recovery characteristics based on low-frequency noise for E-mode GaN HEMTs with p-GaN gate under repetitive short-circuit stress

“…LFN measurements were proven to be an efficient tool to characterize the defects and the density of interface states existing in microelectronic devices [16,17]. To further analyze the effect of repetitive SC stress on the DUTs, the LFN spectrum is obtained under various V gs at V ds = 0.1 V, as graphed in figure 10.…”

Failure Physics and Reliability of GaN‐Based HEMTs for Microwave and Millimeter‐Wave Applications: A Review of Consolidated Data and Recent Results

“…When parasitic GaN buffer conductivity is not controlled due to incomplete compensation, drain-source current leakage is maintained beyond pinch-off, generating a high density of highly energetic carriers or hot electrons, which can induce defects in the AlGaN or GaN layers, through the direct damage of weak lattice bonds or the dehydrogenation of Ga vacancies or N antisites complexes. [51,52] The effect of deep levels can be evaluated by means of pulsed IV transconductance measurements, as shown in Figure 11 (top). A drop in dynamic g m at high V GS without threshold shift is observed in devices with undoped buffer (Figure 11 (top left)), suggesting generation of traps in the gatedrain region.…”