1/f noise reduction in self-aligned AlGaAs/GaAs HBT with AlGaAs surface passivation layer

It is demonstrated that drastic improvement is achieved in base current noise for AlGaAs-passivated full self-aligned AlGaAs/GaAs HBTs, due to extrinsic base recombination current reduction. The base current 1/f noise was over 17 dB lower than that for an non-AlGaAs-passivated HBT, and comparable to that for an AlInAs/InGaAs HBT under a low collector density.<
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