Low frequency and linear high frequency noise performances of AlGaN/GaN grown on SiC substrate

Newly developed GaN technology offers great potential for military and space, as well as some high volume applications. The devices are grown on different substrates (sapphire, silicon and silicon carbide), involving differences on the performances, price, and technological complexity. The design of a fully integrated transceiver in such a technology necessitates great noise performances for the linear (low noise amplifiers, LNA) and non-linear (voltage controlled oscillator, VCO) applications. The low noise figure already published on this technology up to X-band, associated to the capability to handle high power levels avoid the integration of a limiter stage that deteriorates the overall noise figure in conventional architectures. The low frequency noise performances are useful both for the technology assessment (maturity's indicator) and for the non-linear circuit design (conversion to phase noise around the carrier). This paper presents the noise performances of AlGaN/GaN HEMT grown on SiC substrate. Low frequency noise contributors in the ohmic and saturated regime are discussed. Residual phase noise characterization at 10 GHz correlates the results about the noise sources involved, and linear high frequency noise figure measurements are also presented, targeting respectively VCO and LNA applications.