Improved linearity in AlGaN/GaN HEMTs for millimeter-wave applications by using dual-gate fabrication

An effective method of improving the linearity of AlGaN/GaN HEMTs by using dual-gate technology is demonstrated. In this letter, we compare the DC characteristics and device linearity of the dual-gate AlGaN/GaN HEMTs with conventional single-gate AlGaN/GaN HEMTs. The correlation between the extrinsic transconductance (G_m) with third-order intermodulation distortion (IM3) and third order intercept point (IP3) suggests that the broader G_m distribution as a function of gate-bias, causes a lower IM3 level and higher IP3 values for the device. The improved device linearity demonstrates that dual-gate AlGaN/GaN HEMT design is a good approach for high-linearity RF device applications.