AlGaN/GaN HFET电流崩塌效应研究  

Study on Current Collapse of AlGaN/GaN HFET

作　　者：张志国[1,2,3] 冯震[1,2] 杨克武[1,2] 蔡树军[1,2] 郝跃[3] 

机构地区：[1]中国电子科技集团公司第十三研究所,石家庄050051 [2]专用集成电路国家级重点实验室,石家庄050051 [3]西安电子科技大学微电子学院,西安710071

出　　处：《固体电子学研究与进展》2009年第1期27-30,共4页Research & Progress of SSE

摘　　要：电流崩塌效应是限制AlGaN/GaN HFET高输出功率特性的一个重要因素,文中从器件研制的角度研究了AlGaN/GaN HFET的电流崩塌效应。研究结果表明,采用传统的化合物半导体器件细栅工艺制作的器件,栅边缘易发生钻蚀效应,SiN层出现钻蚀区域,器件电流崩塌明显;采用ICP刻蚀SiN后,AlGaN表面产生损伤,电流崩塌效应进一步增强;采用电子束直写方式和SiN钝化,电子未对AlGaN层产生损伤,电流崩塌参量小于20%;采用场板结构,SiN层增加了表面态俘获电子的释放通道,电流崩塌效应得到进一步抑制,减小到小于10%。Current collapse effect is one of the key issues which degenerate the output power of AlGaN/GaN HFET. In this paper, we study this effect by focusing on manufacture process. Experiment results showed that undercutting etching of the SiN passivation layer at the edge of the gate in the conventional III-V process could aggravate the collapse effect. ICP etching process could further enhance the collapse effect due to the plasma damage to the surface. Using E-beam direct writing for device gate and SiN passivation, the degree of current collapse was alleviated to 20% while the number was further reduce to 10% by using field plate, which provided a pass to discharge the trapped charges.

关 键 词：氮化镓 场效应晶体管 电流崩塌效应 氮化硅钝化 刻蚀 场板 

分 类 号：TN305.3[电子电信—物理电子学]