AlGaN/GaN HEMT reliability assessment by means of low frequency noise measurements

Although impressive results have been published for GaN-based transistors in a large frequency range reliability demonstration is becoming an important subject of concern. In this article the conditions of a long term DC life test is presented and a detailed description of pre- and post-test characterization by means of Low Frequency Noise measurements (LFN) is discussed. The transistor parameters (I-DSS, R-on, V-p) and the drain noise spectra presented an evolution strictly related to the biasing point during the stress. This demonstrates that LFN measurement is a useful tool to investigate degradation in GaN HEMTs.