Systematic non-linear model parameter extraction for microwave HBT devices

Abstract

A complete non-linear SPICE model for the heterojunction bipolar transistor (HBT) is presented. The DC and AC characteristics of the HBT are compared with the Gummel-Poon (GP) model used by conventional bipolar junction transistors (BJT) and implemented in simulation and modeling softwares. It is shown that even though the details of HBT operation can differ from those of a BJT, a model and a parameter extraction method can be developed which is compatible with the GP models used for BJT's. A new technique towards estimating starting values of DC and RF model parameters is presented. The small signal equivalent circuit model of an AlGaAs-GaAs heterojunction bipolar transistor (HBT) is also presented. The DC and small signal equivalent circuit parameters are used to build the non-linear SPICE model. >