AlGaN/GaN dual-gate high electron mobility transistors on SiC substrates for high-power mixers

We have demonstrated dual-gate AlGaN/GaN high-electron-mobility transistors on SiC substrates for high-power mixers and examined DC and up-conversion RF measurements with drain-source bias voltages (V_DS) to analyze the possible output level The 0.7×300 μm-gate device exhibited the maximum transconductance of 47 mS, maximum RF power of 19.6 dBm and up-conversion gain of 11 dB at 2 GHz when V_DS = 15 V. For V_DS of over 15 V, the devices occasionally broke down, because, although the device can handle more drain current, but the voltage swing reached the breakdown voltage of about 30 V. These results indicate that a Watt-class output mixer can be easily achieved with this simple dual-gate structure.