K-band Si/SiGe HBT MMIC amplifiers using lumped passive components with a micromachined structure

Using Si/SiGe heterojunction bipolar transistors with a maximum oscillation frequency of 52 GHz and a novel structure for passive components, a two-stage K-band lumped-element amplifier has been designed and fabricated on high-resistivity Si substrates. The chip size including biasing and RF chokes is 0.92/spl times/0.67 mm/sup 2/.