Simulation of high-frequency noise performance of GaN HEMT devices with different barrier layers/ dielectric layers

In this article, the high-frequency noise figure (NF) of the GaN HEMTs with different barrier layers and dielectric layers is simulated by silvaco TCAD. The NF of GaN HEMTs with $\mathrm{Al}_{0.3} \mathbf{G a N}$ and In0.17AlN barrier layer was simulated. The lower carrier effective mass and higher electron saturation velocity ($v_{\text {sat }}$) of the InAIN barrier result in a lower NF. The shot noise is a main component of high-frequency noise. The high gate leakage current of the GaN HEMTs result in the high shot noise. In order to reduce the gate leakage of the GaN HEMTs, the effect of different gate dielectric layers on the noise is also simulated. The simulated dielectric layers, including alumina Al2O3, hafnium oxide $\left(\mathrm{HfO}_{2}\right)$, and silicon oxide $\left(\mathrm{SiO}_{2}\right)$, are 5 nm. Due to the largest bandgap width, the NF of the GaN HEMTs with Al2O3 dielectric layers is lowest.