1-W SiGe power HBTs for mobile communication

SiGe power heterojunction bipolar transistors (HBTs) with 10 and 60×2.25×15 μm
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emitter fingers, respectively, were fabricated in a completely passivated manner by a production-like process. Each emitter stripe of the big transistors includes a ballast resistance of 6 /spl Omega/. Class A load pull measurements at 1.9 GHz revealed a power-added efficiency (PAE) of 44% at 1-W RF output power for the 60-stripes transistor. In addition, a ten-finger driver HBT reached a PAE of 72% at 0.9 GHz for class A/B operation.