Analysis of DC, Channel Temperature, and RF Performance of In Situ SiN/AlGaN-Sandwich-Barrier/GaN/Al₀.₀₅GaN HEMTs

In order to further improve the electrical characteristics of AlGaN-buffer devices, we propose a new in situ SiN/AlGaN-sandwich-barrier (SWB)/GaN/Al_0.05GaN high-electron mobility transistors (HEMTs). The dc, channel temperature, and RF temperature of the proposed AlGaN-buffer devices have been systematically studied and analyzed. The SWB structure can effectively reduce the peak value of the electric field, thus effectively reducing the self-heating effect and improving the breakdown characteristics. Through the channel temperature extraction method of pulsed IV and TCAD thermal simulation, the channel temperature of devices with different barrier structures is compared and analyzed, which proves that SWB structure can effectively reduce the channel temperature of devices. Due to the more obvious potential modulation effect between gate and drain, the f_max of device can improve more effectively with the increase of drain voltage. In addition, load-pull measurement at 10 GHz revealed that a saturated power density increased from 7.3 to 8.4 W/mm and an associated PAE increased from 24.9% to 29.4%.