Advanced IC fabrication technology using reliable, small-size, andhigh-speed AlGaAs/GaAs HBTs

摘要

Reliable, small-size, and high-speed AlGaAs/GaAs HBTs(heterojunction bipolar transistors) have been developed using acarbon-doped thin base layer and O+-implant E/B(emitter/base) junction isolation. This isolation reduces therecombination current at the implanted edge, resulting in improvedcurrent gain. The use of carbon dopant for the base layer improvesdevice reliability. A thin (0.04 μm) base reduces base transit time,making it possible to achieve a high cutoff frequency of 103 GHz. Aone-by-eight static frequency divider and a one-by-four/one-by-fivetwo-modulus prescaler fabricated to investigate circuit performancesuccessfully operated over 10 GHz. The 1-μm×2.4-μm emittersused in the divider are the smallest HBT applied to ICs ever reported.This result indicates that the proposed technology is promising for thedevelopment of reliable and high-speed HBT ICs