Characterization of Parasitic Resistances of AlN/GaN/AlGaN HEMTs Through TCAD-Based Device Simulations and On-Wafer Measurements

This paper shows a detailed characterization and estimation of the temperature-dependent on-resistance RON(T) of AlN/GaN/AlGaN high electron-mobility transistors (HEMTs) through dc and low-frequency (LF) S-parameter measurements. The measurements are carried out at different chuck temperatures (Tchuck) and the RON(T) is calculated for different values of gate-source bias (VGS) of HEMT grown on a silicon carbide (SiC) substrate. Furthermore, we also present the two-dimensional (2-D) physics-based numerical simulation results for the RON(T) extraction of this device. Knowing RON(T) values of the device for different source-drain lengths (LSD), we propose a simplified method to extract the temperature-dependent series contact resistance Rse(T) and channel sheet resistance Rsh(T) of the GaN HEMT technology.