Document Type


Date of Award


Degree Name

Master of Science in Electrical Engineering - (M.S.)


Electrical Engineering

First Advisor

Edip Niver

Second Advisor

Kuohsiung Li

Third Advisor

Gary Wu


The nonlinearity analysis for a 0.5µm gate length microwave GaAs metal-semiconductor field-effect transistor (MESFET) by HP85150B Microwave Design System was investigated. The analysis starts with the construction of a large-signal MESFET equivalent circuit model. This model consists of bias dependent elements that were extracted by the optimization of DC and small-signal S-parameter measurement data. The details on this construction procedure are included in this work. The MESFET third-order intermodulation distortion was then simulated by HP85150B Microwave Design System. Reasonable agreement was obtained between simulation and measurement results. Microwave GaAs MESFET nonlinearity principles and large-signal modeling technique review are also presented. Finally, the basis for a physics-based large-signal analytical model is outlined to the interests of a transistor or MMIC design engineer who is concerned in the microwave performance as function of device design parameters such as gate length and channel doping.