JAPED HomeIssue Contents

An Analytical Approach for Extraction of Extrinsic HBT Parameter by Accurately Accounting the Distributed Nature of Base Resistance
Muhmmad Shah Alam and George Alastair Armstrong

An improved small-signal equivalent circuit model of a HBT including extrinsic resistance, inductance, capacitance and substrate parasitic is presented. The major issue discussed is the importance of paying detailed attention to accurate de-embedding of the many parasitic elements, in order to be able to accurately extract model parameters for the intrinsic transistor. When dealing with the intrinsic transistor a new method of separating base resistance into and extrinsic and intrinsic components is explained and appropriate analytical expressions are derived. The parameter extraction scheme is shown to be valid over a wide range of bias conditions and gives an excellent match to measured S-parameters from 0.25–26.5 GHz.

Keywords: GaAs HBT, Extrinsic parameter extraction, Analytical approach, Small signal modeling.

Full Text (IP)