基于凹槽结构抑制AlGaN/GaN高电子迁移率晶体管电流崩塌效应  

Current collapse suppression in AlGaN/GaN high electron mobility transistor with groove structure

作　　者：刘静[1] 王琳倩 黄忠孝 Liu Jing;Wang Lin-Qian;Huang Zhong-Xiao(Department of Electronic Engineering,Xi’an University of Technology,Xi’an 710048,China)

机构地区：[1]西安理工大学电子工程系

出　　处：《物理学报》2019年第24期347-353,共7页Acta Physica Sinica

基　　金：陕西省重点研发计划(批准号:2019GY-060)资助的课题~~

摘　　要：基于双脉冲技术,研究了GaN缓冲层陷阱对AlGaN/GaN高电子迁移率晶体管电流崩塌效应的影响.结果表明,栅边缘漏侧的电场峰值使得沟道电子跃迁至缓冲层,并被缓冲层中的陷阱俘获是造成电流崩塌的主要原因之一.提出了势垒层局部凹槽结构,降低了栅边缘漏侧的电场峰值,使电场分布更加均匀,改善了器件的电流崩塌效应.与传统AlGaN/GaN高电子迁移率晶体管结构相比,新器件结构对电流崩塌效应的抑制作用至少提升了22.30%.Due to the excellent properties of GaN,such as wide band gap,high electron mobility,high saturation speed,and high breakdown electric field,AlGaN/GaN high electron mobility transistor(HEMT)possesses highly promising applications in the fields of high power,radio frequency,and high temperature applications.However,they are still subjected to the influence of current collapse which strangles its development.Based on the double-pulse technique,the effect of GaN buffer layer trap on the current collapse of AlGaN/GaN HEMT is studied.The results show that the electric field peak at the gate edge is one of the main causes of current collapse.The channel electrons are trapped by the buffer trap under the peak electric field.Because the response speed of the trap in the buffer layer is slow,the channel can not be turned on immediately after the gate voltage has jumped to 0 V,which leads the current to collapse.In this paper,the new structure is proposed by introducing a groove structure in the barrier layer.The channel two-dimensional electron gas is modulated by the groove structure,which influences the channel electric field of AlGaN/GaN HEMT device,reduces the electric field peak at the gate edge,and improves the current collapse effect of the device.Comparing with the traditional AlGaN/GaN HEMT,the inhibition effect of the new device structure on current collapse is increased by 22.30%.The length and height of the groove structure are the critical parameters to affect the new HEMT performance.The optimal parameters of length and hight show that when the length of the groove is 1μm and the height is 0.01μm,the current collapse of HEMT and its performance are significantly improved.

关 键 词：ALGAN/GAN 高电子迁移率晶体管 电流崩塌效应 缓冲层陷阱 

分 类 号：TN3[电子电信—物理电子学]