Abstract
70-nm T-gate InP-based low noise In0.52Al0.48As/In0.65Ga0.35As pseudomorphic high electron mobility transistor (PHEMT) with well-balanced cutoff frequency ft and maximum oscillation frequency fmax were designed and fabricated. DC, RF, and noise characterizations are demonstrated. The maximum saturation current density Idss and maximum extrinsic transconductance gm,max are measured to be 894 mA/mm and 1640 mS/mm, respectively. And the extrapolated ft and fmax based on inflection point were 247 GHz and 392 GHz, respectively. Due to the disadvantages of traditionally used Y-factor method, the new cold-source method was adopted to measure the noise parameters. The minimum noise figure (NFmin) is 1 dB at 30 GHz associated with a gain of 15 dB at Vds of 0.8 V and Ids of 17 mA. These excellent results make this InP-based PHEMT one of the most suitable devices for millimeter wave low noise applications.
