The evolution of packages for monolithic microwave andmillimeter-wave circuits

The maturing of monolithic microwave integrated circuit (MMIC) technology has spawned a variety of new military and commercial applications. As-a result, there is an increased emphasis on the packaging of MMIC chips and MMIC-based components. Currently, the industry is applying a number of new assembly and packaging technologies to RF components and subsystems driven by the forces of performance, size and weight, and cost. This paper outlines the current evolution in microwave and millimeter-wave packaging using examples drawn from the area of active array antennas     

Off-state breakdown effects on gate leakage current in powerpseudomorphic AlGaAs/InGaAs HEMTs

The effects of off-state breakdown on characteristics of power AlGaAs/InGaAs pseudomorphic HEMTs (PHEMTs) are investigated in detail. While the gate leakage current is substantially decreased after breakdown stress, no obvious changes in drain-to-source current and transconductance are observed. Prior to breakdown stress, gate leakage current shows a nearly ideal 1/f noise characteristic with an Ig² dependence, suggesting a surface generation-recombination current from the interface of the passivation layer. After stress, the gate current noise can be drastically reduced. The results suggest an alternative for alleviating the gate leakage current in PHEMTs     

Single-diode 0.5kW TRAPATT oscillator

A lumped-element TRAPATT-diode oscillator capable of more than 0.5 kW output power from a single diode chip is described. Peak power of 575 W with 23% efficiency and a maximum efficiency of 28% at 0.5 kW output power have been consistently obtained at approximately 1 GHz.