AlGaN/GaN HEMTs on Silicon Substrate With 206-GHz $F_{ rm MAX}$

摘要

This letter reports on AlGaN/GaN high-electron-mobility transistors (HEMTs) on high-resistive silicon substrate with a record maximum oscillation cutoff frequency $F_{rm MAX}$ . Double-T-shaped gates are associated with an optimized technology to enable high-efficiency 2-D electron gas control while mitigating the parasitic resistances. Good results of $F_{rm MAX} =break hbox{206} hbox{GHz}$ and $F_{T} = hbox{100} hbox{GHz}$ are obtained for a 90-nm gate-length HEMT with 0.25-$ muhbox{m}$ source-to-gate spacing. The associated peak extrinsic transconductance value is as high as 440 $hbox{mS}cdothbox{mm}^{-1}$. To the authors' knowledge, the obtained $F_{rm MAX}$ and $Gm_{rm ext}$ are the highest reported values for GaN HEMTs technology on silicon substrate. The accuracy of the cutoff frequency values is checked by small-signal modeling based on extracted S-parameters.