增强型AlGaN/GaN高电子迁移率晶体管高温退火研究  

High temperature annealing of enhancement-mode AlGaN/GaN high-electron-mobility transistors

作　　者：王冲[1] 全思[1] 马晓华[1] 郝跃[1] 张进城[1] 毛维[1] 

机构地区：[1]宽禁带半导体材料与器件重点实验室西安电子科技大学微电子学院,西安710071

出　　处：《物理学报》2010年第10期7333-7337,共5页Acta Physica Sinica

基　　金：国家科技重大专项(批准号:2008ZX01002-002);国家自然科学基金重大项目(批准号:60890191);国家自然科学基金重点项目(批准号:60736033);中国国防科技预研基金(批准号:51308030102);西安电子科技大学回国人员创新基金资助的课题~~

摘　　要：深入研究了两种增强型AlGaN/GaN高电子迁移率晶体管(HEMT)高温退火前后的直流特性变化.槽栅增强型AlGaN/GaN HEMT在500℃N2中退火5min后,阈值电压由0.12V正向移动到0.57V,器件Schottky反向栅漏电流减小一个数量级.F注入增强型AlGaN/GaN HEMT在400℃N2中退火2min后,器件阈值电压由0.23V负向移动到-0.69V,栅泄漏电流明显增大.槽栅增强型器件退火过程中Schottky有效势垒提高,增强了栅对沟道载流子的耗尽能力,使器件阈值电压正方向移动,同时降低了栅反向漏电流,而且使得栅能工作在更高能的正向栅压下.F注入增强型器件在退火后由于F离子对二维电子气的耗尽作用在退火后减弱,造成阈值电压负方向移动;F注入对势垒的提高作用在退火后有所减弱,引起了Schottky泄漏电流明显增大.退火后F注入增强型器件的沟道电子迁移率得到明显恢复。The high temperature annealing effect of DC characteristics of the different enhancement-mode AlGaN /GaN highelectron-mobility transistors（HEMTs） were investigated.The threshold voltage shifted from 0.12 V to 0.57 V and the gate leakage current was reduced one order after the recessed-gate enhancement-mode AlGaN /GaN HEMTs were annealed at 500 ℃ for 5 min in N2 atmosphere.The threshold voltage shifted from 0.23 V to-0.69 V and the gate leakage current increased after the F-implantation enhancement-mode AlGaN /GaN HEMTs were annealed at 400 ℃ for 2 min in N2 atmosphere.The height of Schottky barrier increased in annealing process that enhanced the depletion of gate to channel electrons,so that the threshold voltage shifted in the positive direction of x axis,the gate leakage current was reduced and the device can work at higher gate voltage.The depletion of F ions and the increased barrier height of F ions were weakened after annealing,so that the threshold voltage shifted in negative direction of x axis and the gate leakage current increased.The channel electron mobility of F-implantation enhancement-mode AlGaN /GaN HEMTs increased obviously after annealing process.

关 键 词：高电子迁移率晶体管 ALGAN/GAN 增强型器件 

分 类 号：TN386[电子电信—物理电子学]