Influence of the heterostructure design on noise figure of AlGaN/GaN HEMTs

In this work, we cover four topics. Three studies are presented on the effect of different epilayer structures on the noise figure of AlGaN/GaN HEMTs in the 4-12 GHz frequency range. The material studies include varying aluminum composition in the barrier, sapphire vs. SiC substrates, and, for the first time, the influence of a thin AlN layer on the noise parameters; all three against frequency and drain current. In addition is a comparison of two equivalent circuit models at 5 GHz.