Insertion loss and linearity of III-nitride microwave switches



We report the insertion loss and linearity characteristics of novel microwave switches based on III-Nitride heterostructure field-effect transistors (HFETs) and Metal-Oxide-Semiconductor HFETs (MOSHFETs). The high mobility and large sheet carrier density make nitride-based microwave switches ideal candidates for high power, low loss and high linearity microwave switching applications. The demonstrated SPDT switch achieved the third order intermodulation power of -68 dBm for 250 micron devices at 1 GHz and 10 dBM input power and the extrapolated IP3 of >80 dBm with <0.25 dB insertion loss and >35 dB isolation for 2GHz operation for 3mm devices. Further improvements of the insertion loss and linearity are expected from new material and contact development, which will achieve lower 2DEG sheet resistance and contact resistance. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)