Title

Bias, frequency, and area dependencies of high frequency noise in AlGaAs/GaAs HBT's

Abstract

-The noise figure of the heterojunction bipolar transistor (HBT) in the microwave frequency range is studied, and an improved physical noise model is developed. Unlike the conventional high frequency noise model, which considers only the bias current dependence, the present model includes both the effects of voltage and current on the noise behavior. In addition, the frequency- and area-dependent natures of the HBT noise at very high frequencies are incorporated in the model. It is found that the voltage dependence of the high frequency noise in the HBT results from the self-heating effect, which gives rise to a higher IIBT lattice temperature than the ambient temperature. Also, the free-carrier transport delay time must be considered to properly model the frequency dependence of noise since the inverse of this time is comparable with the frequency. Furthermore, the area dependence of noise is dominated by changes in the base resistance and emitter-base junction capacitance. Results for the minimum noise factor calculated from the model compare favorably with those obtained from measurements. © 1996 IEEE.

Publication Date

12-1-1996

Publication Title

IEEE Transactions on Electron Devices

Volume

43

Issue

1

Number of Pages

116-122

Document Type

Article

Personal Identifier

scopus

DOI Link

https://doi.org/10.1109/16.477601

Socpus ID

0029751449 (Scopus)

Source API URL

https://api.elsevier.com/content/abstract/scopus_id/0029751449

This document is currently not available here.

Share

COinS