Power performance and scalability of AlGaN/GaN power MODFETs

The scalability of power performance of AIGaN/GaN MODFETs with large gate p eriphery, as necessary for microwave power del;ices. is addressed in this p aper. High-frequency large-signal characteristics of AIGaN/GaN MODFETs meas ured at 8 GHz are reported for devices with gatewidths from 200 mu m to 1 m m, 1-dB gain compression occurred at input power levels varying from -1 to +10 dBm as the gatewidth increased, while gain remained almost constant at similar to 17 dB, Output power density was similar to 1 W/mm for all device s and maximum output power (29.9 dBm) occurred in devices with I-mm gates, while power-added efficiency remained almost constant at similar to 30%. Th e large-signal characteristics were compared with those obtained by de and small-signal S-parameters measurements, The results illustrate a notable sc alability of AICaN/GaN MODFET power characteristics and demonstrate their e xcellent potential for power applications.