A Compact 30-W AlGaN/GaN HEMTs on Silicon Substrate With Output Power Density of 8.1 W/mm at 8 GHz

A 29.4-W X-band high-power amplifier has been substantialized using GaN on high-resistive silicon substrate. The developed GaN high electron mobility transistor (HEMT) with 3.6-mm gate periphery provides 29.4-W output power and 8-dB small signal gain at 8 GHz with power added efficiency of 39.4% under pulse condition at a duty of 10% with a pulsewidth 100 μs. Load-pull measurement at 8 GHz demonstrates an output power density of 8.1 W/mm. To the best of our knowledge, the presented amplifier exhibits the highest power density, delivering >10 W of output power in X-band for GaN HEMTs technology on silicon substrate.