Effect of Dielectric Thickness on Power Performance of AlGaN/GaN HEMTs

The effect of $\hbox{SiN}_{x}$ passivation thickness on the power performance of AlGaN/GaN high-electron-mobility transistors (HEMTs) has been studied. A model is proposed to explain the surface-state dispersion and passivation of AlGaN/GaN HEMTs. Based on this model, a multidielectic passivation method has been proposed and demonstrated to both provide lower dielectric capacitance and help remove dc–RF dispersion.