|
In recent years, the solid-state semiconductor devices in the field of microwave power amplifier is gradually replaced the vacuum tube , which AlGaN / GaN HEMT with high transconductance , high saturation current , low noise , high breakdown voltage , high temperature and other characteristics , is to replace the vacuum tube The main candidates . From the device structure , polarization effects , DC devices , and high-frequency performance of AlGaN / GaN HEMT modeling , simulation and optimization . AlGaN / GaN HEMT modeling , the paper first application of the ISE-TCAD software AlGaN / GaN HEMT simulation model . In order to improve the simulation accuracy , select the material parameters of the more suitable for the simulation of GaN, AlN and AlGaN . Set on the basis of physical simulation equations and models , including the Poisson equation , continuity equation , a statistical model of the carrier ( Fermi - Dirac distribution ) , transport models ( hydrodynamic model ) and the composite model ( Schottky - Reed - Hall model ). The paper created by the AlGaN / GaN HEMT correction model integrated simulation derived from the aspects of the device structure , charge distribution , the current characteristic and the frequency characteristic of the energy band diagram , the density of the two - dimensional electron gas , the transfer characteristic curves and output characteristics . Paper the experimental value of the simulation results and related references contrast thesis results with the experimental value trends agreement , which initially verify the correctness of simulation results , the same time, the simulation results and experimental literature part of the cause of the deviation of the value of the preliminary analysis . Thesis established HEMT model the device polarization charge density AlGaN surface donor trap density , contact resistance , AlGaN layer thickness and gate-to-source distance optimization . Optimization is based on the scanning, the main parameters according to the variation of parameters and the device performance , is selected in the range of process allows optimization parameters, to improve the performance of the device from the threshold voltage, the drain saturation current and peak transconductance . Thesis work on AlGaN / GaN HEMT device modeling , simulation and optimization of a useful attempt , initially obtained the guiding principles and methods of optimization of the device , on the basis of the paper work , and follow-up to a more in-depth study from more accurate the polarization model hot electron effect devices fronts .
|