一种降低GaN HEMT沟道温度的新结构  

A new structure for reducing the channel temperature of GaN HEMT

作　　者：李佳[1] 陈万军[1] 孙瑞泽[1] 信亚杰 LI Jia;CHEN Wan-jun;SUN Rui-ze;XIN Ya-jie(School of Electronic Science and Engineering,University of Electronic Science and Technology of China,Chengdu 610054,China)

机构地区：[1]电子科技大学电子科学与工程学院,四川成都610054

出　　处：《微电子学与计算机》2020年第8期27-31,36,共6页Microelectronics & Computer

基　　金：国家自然科学基金项目(60906037,61274090)。

摘　　要：针对氮化镓高电子迁移率晶体管(GaN HEMT)沟道温度过高导致器件性能下降的问题,提出一种降低GaN HEMT沟道温度的新结构,通过优化沟道电场来降低沟道温度.该结构采用混合势垒层设计,将栅极下方的势垒层分为两层,上层采用AlN,下层采用重掺杂的AlGaN;此外,该结构还使用场板;为了更好的散热,该结构采用热导率更高的AlN代替传统的Si3N4作为器件的钝化层.场板和混合势垒层有利于改善沟道电场,降低器件沟道温度.仿真结果表明,相比于传统结构,新结构的沟道温度分布更加均匀,温度峰值下降47 K.此外,新结构的击穿电压提高50%,输出特性也得到了改善.When the channel temperature of GaN high electron mobility transistor(GaN HEMT)is too high,the performance of the device is degraded.To solve this problem,a new structure is proposed,the channel temperature is reduced by optimizing the electric field.The barrier layer under the new structure gate is called the mixed barrier layer,which consists of two layers,the upper layer is AlN and the lower layer is heavily doped AlGaN.In addition,the field plate is also introduced to change the channel electric field.For better heat dissipation,the passivation layer material of the new structure is AlN instead of Si3N4,because it has a higher thermal conductivity.Compared with the traditional structure,the channel temperature distribution of the new structure is more uniform,and the channel temperature peak drops by 47 K.In addition,the breakdown voltage of the new structure is increased by 50%,and the output characteristics are also improved.

关 键 词：氮化镓(GaN) 高电子迁移率晶体管(HEMT) 沟道温度 混合势垒层 

分 类 号：TN386[电子电信—物理电子学]