高线性度Al_xGa_(1-x)N/Al_yGa_(1-y)N/GaN高电子迁移率晶体管优化设计

对新型复合沟道AlxGa1-xN/AlyGa1-yN/GaN高电子迁移率晶体管(HEMT)进行了优化设计.从半导体能带理论与量子阱理论出发,自洽求解了器件层结构参数对器件导带能级以及二维电子气(2DEG)中载流子浓度和横向电场的影响.用TCAD软件仿真得到了器件的层结构参数对器件性能的影响.结合理论分析和仿真结果确定了器件的最佳外延层结构Al0.31Ga0.69N/Al0.04Ga0.96N/GaNHEMT.对栅长1μm,栅宽100μm的器件仿真表明,器件的最大跨导为300mS/mm,且在栅极电压-2—1V的宽范围内跨导变化很小,表明器件具有较好的线性度;器件的最大电流密度为1300mA/mm,特征频率为11.5GHz,最大振荡频率为32.5GHz.

Optimization design of high linearity Al_xGa_(1-x)N/Al_yGa_(1-y)N/GaN high electron mobility transistor

A novel composite-channelAl_xGa_(1-x)N/Al_yGa_(1-y)N/GaN high electron mobility transistor has designed and optimized.The influence of the two-dimensional electron gas and electric field on device structure parameter is obtained from the self-consistent solution based on the theory of semiconductor energy band and quantum well.The influence of the layer structure of the device on its performance is obtained from simulation using TCAD software.Combining the results of theoretical analysis and simulation, the optimized structure Al_(0.31)Ga_(0.69)N/Al_(0.04)Ga_(0.96)N/GaN HEMT is proposed.The simulation results show that the device with gate length of 1 μm and gate width of 100 μm has the maximum transcouductance of 300 mS/mm and small fluctuation in the gate voltage of from-2 V to 1 V, which shows the excellent linearity of the device.The maximum current density of 1300 mA/mm, the cut-off frequency of 11.5 GHz and a maximum oscillation frequency of 32.5 GHz are obtained.