Research On The Physical Based Large Signal Model Of Microwave GaN HEMT Power Devices

In order to meet the increasing performance of communication system,it is necessary to develop more powerful microwave power devices.High electron mobility transistors(HEMTs)made of Gan materials are widely used in microwave circuits because of their high frequency,high power and high efficiency.The semiconductor device model can undertake the process production of the device downward,improve the process level,undertake the circuit design of the device upward,and shorten the design cycle.It is an indispensable key part of the whole semiconductor industry chain,so it is very meaningful to establish an accurate model for GaN HEMT devices.At present,there are many reports about the empirical basis model for GaN HEMT,but the empirical basis model contains a lot of empirical parameters and lacks physical significance,so it can not guide the device design.Therefore,it is necessary to establish a physical based large signal model and establish the direct relationship between microwave characteristics and physical parameters of the device.The research content of this paper includes:1.Starting from the small signal equivalent circuit modeling and based on the theory of region division and large signal model,a physical based large signal model is established for microwave GaN HEMT power devices with gate length of 0.25 ?m and gate width of 10?125 ?m,and a complete set of parameter extraction flow of microwave GaN HEMT physical based model is established.Compared with the simulation results and the actual measurement results,the error of the physical based large signal model is controlled within 15%,which proves that the physical based large signal model based on region division has high accuracy and good engineering application.2.Based on the region division model of small power single cell devices,based on the lumped parameter and the scaling modeling theory of multi cell parallel connection,the scaling model of GaN HEMT multi cell devices with gate length of 0.25 ?m is established,which further improves the engineering application of the region division physical base model.In order to further verify the accuracy of the model,this paper also applies the multicellular large signal model to an S-band power amplifier,and the circuit simulation results obtained by using the scaling model have 12% model error compared with the requirements of the actual device,which shows the GaN based on region division HEMT physical based large signal scaling model has high precision and can be used in circuit design and analysis.