Abstract: A Ka-band GaN amplifier MMIC has been designed in CPW technology, and fabricated with a domestic GaN epitaxial wafer and process. This is, to the best of our knowledge, the first demonstration of domestic Ka-band GaN amplifier MMICs. The single stage CPW MMIC utilizes an AlGaN/GaN HEMT with a gate-length of 0.25 μm and a gate-width of 2 × 75 μm. Under V_ds = 10 V, continuous-wave operating conditions, the amplifier has a 1.5 GHz operating bandwidth. It exhibits a linear gain of 6.3 dB, a maximum output power of 22 dBm and a peak PAE of 9.5% at 26.5 GHz. The output power density of the AlGaN/GaN HEMT in the MMIC reaches 1 W/mm at Ka-band under the condition of V_ds = 10 V.

Key words: GaN