Anomaly and defects characterization by I-V and current deep level transient spectroscopy of Al0.25Ga0.75N/GaN/SiC high electron-mobility transistors

作者：Saadaoui Salah; Ben Salem Mohamed Mongi; Gassoumi Malek; Maaref Hassen; Gaquiere Christophe

来源：Journal of Applied Physics, 2012, 111(7): 073713.

DOI：10.1063/1.3702458

In this paper, we report static electric drain-source current-voltage measurements for different gate voltages and at different temperatures, performed on Al0.25Ga0.75N/GaN/SiC high electron-mobility transistors (HEMT). The results show the presence of kink and collapse effects. We have demonstrated that these effects are significant in the temperature range varying from 150 to 400 K with a maximum around 300 K. This parasitic effect was correlated with the presence of deep levels in our transistor. Indeed, we have noticed the presence of two electron traps named A(1) and A(2), and one hole trap named H-1; their respective activation energies, which are determined using current deep level transient spectroscopy (CDLTS), are, respectively, 0.56, 0.82, and 0.75 eV. Traps H-1 and A(1) are shown to be extended defects in the Al0.25Ga0.75N/GaN heterostructure; they are supposed to be the origin of the kink and collapse effects. However, the punctual defect A(2) seems to be located either in the free gate-drain surface, in the metal/AlGaN interface, or in the AlGaN/GaN interface.

• 出版日期2012-4-1