高电流增益截止频率的AlGaN/GaN HEMT器件研制  

Research and Development of AlGaN/GaN HEMT Devices with High Current Gain Cut-off Frequency

作　　者：邹学锋[1] 吕元杰[2] 宋旭波[1] 郭红雨[1] 张志荣[1] Zou Xuefeng Lu Yuanjie Song XLibo Guo Hongyu Zhang Zhirong(The 13th Researeh Institute, CETC, Shijiazhuang 050051, China Science and Technology on ASIC Laboratory, Shijiazhuang 050051, China)

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]专用集成电路重点实验室,石家庄050051

出　　处：《半导体技术》2017年第2期103-107,114,共6页Semiconductor Technology

基　　金：国家自然科学基金资助项目(61306113)

摘　　要：基于金属有机化学气相沉积(MOCVD)再生长Si重掺杂的n+GaN工艺,在AlGaN/GaN高电子迁移率场效应晶体管(HEMT)中实现非合金的欧姆接触,该工艺将器件有效源漏间距缩小至1μm。结合60nm直栅工艺,制备了高电流增益截止频率(fT)的AlGaN/GaNHEMT器件。器件尺寸的缩小大幅提升了器件的直流和射频特性。漏偏压为5V下,器件的最大直流峰值跨导达到440mS/mm;栅偏压为1V时,最大漏源饱和电流密度达到1.68A/mm。根据射频小信号测试结果得到器件的fT达到175GHz,最大振荡频率(fmax)达到76GHz,研究了干法刻蚀对再生长n+GaN欧姆接触电阻的影响,同时对比分析了60nm直栅和T型栅对器件频率特性的影响。Nonalloyed ohmic contacts were realized in AlGaN/GaN high electron mobility transistors（HEMTs） with regrown heavily-Si-doped n＋-Ga N by metal organic chemical vapor deposition（MOCVD）. Using the regrown n＋-Ga N ohmic contacts,the virtual source-to-drain distance was reduced to 1 μm. AlGaN/GaN HEMTs with high current gain cut-off frequency（fT） were fabricated with the60 nm rectangular gate technology. The reduction in device size improves the DC and RF characteristics of the device greatly. The fabricated AlGaN/GaN HEMT device exhibits a maximum DC peak transconductance of 440 m S/mm at the drain bias of 5 V,and a maximum drain-source saturation current density of 1. 68 A/mm at the gate bias of 1 V. Moreover,based on the RF small signal test results,the fTof175 GHz and a maximum oscillation frequency（fmax） of 76 GHz are achieved. The effects of dry etching on the regrown n＋-Ga N ohmic contact resistance were investigated. Meanwhile, the influences of the60 nm rectangular and T-shaped gates on the frequency characteristics of AlGaN/GaN HEMTs were compared and analyzed.

关 键 词：ALGAN/GAN 再生长n+GaN 非合金欧姆接触 纳米栅 电流增益截止频率 

分 类 号：TN386[电子电信—物理电子学]