The Simulation And Reasearch Of AlGaN/GaN HEMT

This paper completed the DFM (Design-For-Manufacturability) of AlGaN/GaN HEMT (High Electron Mobility Transistor) with A1N add layer form structure level and physics properties level. This device has 5A A1N add layer,22.5nm AlGaN barrier layer and the gate length of the device is 60um. According to the structure size and experimental results, the author put forward this device's design scheme. This design got the dc characteristic and C-V characteristic curve, forecasted the high frequency characteristics, and analyzed the influence of the main parameters driven on the device characteristics deeply. Based on the simulation results, we modified the model parameters constructively, discussed how does several parameters impacts on the device's characteristics, thus got the optimum design schemes for DEM by optimization.This paper first generalized the research actuality of AlGaN/GaN HEMT inside and outside of the country, put forward the study significance and applied values; Secondly, this paper introduced the working principle of AlGaN/GaN HEMT simply, including the AlGaN/GaN material properties, heterojunction characteristics and the polarization effect. Then proposed a structure simulation program based on the device structure index, explored the rules of mesh design, and made the mesh sufficiently tight around 2DEG (Two Dimensional Electron Gas) regions and the hot electrons regions. This paper dwelt on the physical models which were chosen in this topic, and adjusted part parameters of these models, such as SRH (Shockley-Read-Hall) recombination model, hydrodynamic model, high-field mobility model, band gap model and so on. This subject discussed the establishment of polarization effect model importantly, and given the specific calculation formula. Finally, we put forward the physical characteristics simulation program based on all the models which was mentioned previous. Finally we got the high frequency characteristic, predicted the maximum transconductance, highest cut-off frequency and the maximum oscillation frequency, and further discussed the effect on the device characteristics, the parameters including Al components, A1N inserted layer thickness, AlGaN barrier layer thickness, strain relaxation degree, and the gate length.This subject got the simulation schemes by screening and fixing the simulation models to make the simulation results similar to the experiment data. This scheme used Sentaurus Structure Editor (SDE) completed the structure design, used Sentaurus Device realized the physical properties simulation and finished the optimization under the Sentaurus Work Bench (SWB) integration platform eventually.The core work of this job is established the polarization effect model of AlGaN/GaN HEMT with A1N intercalated layer. This paper simulate the impact of polarization effect by defining the polarizing charge separately, finally defined the interface charge of AlGaN/A1N and A1N/GaN interface and the surface charge of AlGaN surface.The main contribution of this subject is realized the DFM of A1GaN/GaN HEMT with A1N inserted layer form structure level and physics properties level, this work has not been reported inland. Established the polarization model, this paper described the impact of polarization effect from the aspects of polarizing charge.This paper's DFM design scheme and implementation of AlGaN/GaN HEMT solved many technology problems, such as the grid settings, the models optimizations, convergence problem, etc. All these research results in this paper provides strong reference for the further study of AlGaN/GaN HEMT, has certain practical values.