Analysis of traps effect on AlGaN/GaN HEMT by luminescence techniques

The study is carried out on AlGaN/GaN HEMTs presenting current collapse effect at Vds lower than 6 V. This effect is completely recovered by illuminating the component with light of 710 nm wavelength (1.75 eV). The spectral analysis of the light emission in the visible near infrared spectrum shows a bell-shape with superimposed distinct emission peaks. These features suggest that the electroluminescence (EL) signal is due to the direct intraband of electrons and inelastic intraband transition of electrons due to scattering by charged centres. Photoionisation experiments have been conducted to determine the light wavelengths/energies that separately change the drain current and the gate leakage current.