Relaxation of low-frequency noise in AlGaN/GaN HEMTs

In this contribution we report on low-frequency (LF) noise spectra of aluminium gallium nitride / gallium nitride (AlGaN/GaN) high electron mobility transistors (HEMTs) subjected to the illumination by photons of energy E_ph bellow the energy band gap E_g of GaN. Change of LF noise spectra of the drain voltage noise and the gate current noise during the illumination and its slow relaxation to initial value after the illumination termination during the first 10 minute interval have been observed. These changes were related to time dependent changes of operating parameters (V_DS, I_DS and I_GS) and discussed in terms of the traps located in AlGaN/GaN HEMT structure.