Research On Large Signal Model Of GaAs PHEMT Switch Device

Gallium arsenide(GaAs)are important wide-gap semiconductor compound widely used in modern wireless communication systems and optoelectronic systems.GaAs PHEMT switching devices have occupied an important position in microwave radio frequency switch and derivative market with low insertion loss,high stability,good linearity and low cost alongwith its development.Device model also plays a guiding and decisive role in the design of radio frequency switches and other circuits.High-precision device model is crucial not only in characterizing electrical characteristics of the device,but also indispensable in improving device performance,which shorten the designing and marketing period.This paper focuses on presenting a large-signal model of GaAs PHEMT switching devices.Its research work are as follows:1.GaAs PHEMT switching device large-signal model selection.Firstly,the topological structure,current and charge equations of the three popular empirical-based nonlinear models(Angelov,EEHEMT,Curtice3)are discussed.Then,combining the output,transfer and other characteristics of the simulation and measurement curves from three empirical models applied to the switching devices with the same conditions2.Establishment and verification of small signal model of GaAs PHEMT switching device.Combining the theoretical basis of related switching devices in Chapter 2 and the differences between single-gate and multi-gate switching devices,the construction of the small signal topology based on Angelov-based switching devices and the extraction of parameters are completed.The quantified channel resistance is the middle term,and the parasitic parameters are extracted quickly and accurately from the single-gate device model,and the intrinsic parameters are extracted from the multi-gate device model.In the frequency range from 0.1 GHz to 20.1 GHz,the relative error of S₁₁in the on-state of the multi-gate device remains below 15%,and the relative error in the off-state is no more than 2%;the relative error of the on-state S₁₂is only 1.89%,less than 2%,while in the off-state The relative error of S₁₂is less than 13%.3.Research and verification of large signal model of GaAs HEMT switching device.A Angelov model's parameter extraction process is proposed.Through the fitting results of measurement data and simulation data of devices with different gate types and different gate widths in the frequency band of 0.1-20 GHz,the verification of the characteristics of DC,AC,and power has been completed.Finally,the two most important performances of switching devices(isolation,Insertion loss)are summarized.