Analysis of the ohmic contacts of Ti/Al/Ni/Au to AlGaN/GaN HEMTs by the multi-step annealing process  

作　　者：颜伟 张仁平 杜彦东 韩伟华 杨富华 

机构地区：[1]Engineering Research Center for Semiconductor Integrated Technology,Institute of Semiconductors,Chinese Academy of Sciences

出　　处：《Journal of Semiconductors》2012年第6期31-36,共6页半导体学报（英文版）

基　　金：supported by the National Basic Research Program of China(No.2010CB934104)

摘　　要：The multi-step rapid thermal annealing process of Ti/Al/Ni/Au can make good ohmic contacts with both low contact resistance and smooth surface morphology for AlGaN/GaN HEMTs.In this work,the mechanism of the multi-step annealing process is analyzed in detail by specific experimental methods.The experimental results show that annealing temperature and time are very important parameters when optimizing the Ti/Al layer for lower resistance and the Ni/Au layer for smooth surface morphology.It is very important for good ohmic contacts to balance the rate of various reactions by adjusting the annealing temperature and time.We obtained a minimum specific contact resistance of 3.22×10^（17）Ω·cm^2 on the un-doped AlGaN/GaN structure with an optimized multistep annealing process.The multi-step rapid thermal annealing process of Ti/Al/Ni/Au can make good ohmic contacts with both low contact resistance and smooth surface morphology for AlGaN/GaN HEMTs.In this work,the mechanism of the multi-step annealing process is analyzed in detail by specific experimental methods.The experimental results show that annealing temperature and time are very important parameters when optimizing the Ti/Al layer for lower resistance and the Ni/Au layer for smooth surface morphology.It is very important for good ohmic contacts to balance the rate of various reactions by adjusting the annealing temperature and time.We obtained a minimum specific contact resistance of 3.22×10^（17）Ω·cm^2 on the un-doped AlGaN/GaN structure with an optimized multistep annealing process.

关 键 词：AlGaN GaN high electron mobility transistor annealing ohmic contact 

分 类 号：TN303[电子电信—物理电子学]