场板结构对AlGaN/GaN HEMT温度场的影响

The Influence of Field Plate Structure on Temperature Field of AlGaN/GaN HEMT

用Silvaco的ATLAS软件仿真研究了场板结构对AlGaN/GaN高电子迁移率晶体管(HEMT)的温度场分布的影响,分析了场板结构影响器件温度场分布的可能因素。模拟结果表明,加入场板结构后,器件沟道二维电子气浓度减小,电场分布发生变化,器件栅极漏侧边缘处的沟道峰值温度降低。加入栅场板和源场板结构后,场板边缘处都有一个新的温度峰值出现,器件的沟道温度峰值在加入单层和双层栅场板及源场板后由511K分别下降到487、468和484K,这种降低作用会随着栅场板层数的增加而有所增强。仿真结果说明场板结构通过改变AlGaN/GaN HEMT器件沟道载流子浓度和电场分布,影响器件内部的温度场分布。优化器件的场板结构是提高AlGaN/GaN HEMT的可靠性有效途径之一。

The influence of field plate structure on the temperature field distribution of AlGaN/GaN high electron mobility transistors（HEMTs）was simulated by ATLAS of Silvaco software.The possible factors that affect the temperature distribution of the field plate were analyzed.Simulation results show that after introducing the field plate the two-dimensional electron gas concentration in the channel decreases,the electric field distribution changes,and thus the peak temperature at the gate edge of drain-side decreases.After adding gate and source field plate,new temperature peaks occur at the field plate edge.The temperature peak of the device decreases from 511 Kto 487 K,468 Kand 484 K when the single,double gate field plate and sourse field plate were added respectively.And the reduction of peak temperature will increase as the number of gate field plates increases.The simulation results show that the field plate structure influences the temperature distribution in the AlGaN/GaN HEMT by changing the channel carrier concentration and the electric field distribution.Optimizing the field plate structure is one of the effective approaches to improve the temperature reliability of AlGaN/GaN HEMTs.