Influence of ultra-thin TiN thickness(1.4 nm and 2.4 nm) on positive bias temperature instability(PBTI)of high-k/metal gate nMOSFETs with gate-last process  

作　　者：祁路伟 杨红 任尚清 徐烨峰 罗维春 徐昊 王艳蓉 唐波 王文武 闫江 朱慧珑 赵超 陈大鹏 叶甜春 

机构地区：[1]Key Laboratory of Microelectronics Devices and Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences

出　　处：《Chinese Physics B》2015年第12期499-502,共4页中国物理B（英文版）

基　　金：Project supported by the National High Technology Research and Development Program of China(Grant No.SS2015AA010601);the National Natural Science Foundation of China(Grant Nos.61176091 and 61306129)

摘　　要：The positive bias temperature instability（PBTI） degradations of high-k/metal gate（HK/MG） n MOSFETs with thin TiN capping layers（1.4 nm and 2.4 nm） are systemically investigated. In this paper, the trap energy distribution in gate stack during PBTI stress is extracted by using ramped recovery stress, and the temperature dependences of PBTI（90℃,125℃, 160℃） are studied and activation energy（Ea） values（0.13 eV and 0.15 eV） are extracted. Although the equivalent oxide thickness（EOT） values of two TiN thickness values are almost similar（0.85 nm and 0.87 nm）, the 2.4-nm TiN one（thicker Ti N capping layer） shows better PBTI reliability（13.41% at 0.9 V, 90℃, 1000 s）. This is due to the better interfacial layer/high-k（IL/HK） interface, and HK bulk states exhibited through extracting activation energy and trap energy distribution in the high-k layer.The positive bias temperature instability（PBTI） degradations of high-k/metal gate（HK/MG） n MOSFETs with thin TiN capping layers（1.4 nm and 2.4 nm） are systemically investigated. In this paper, the trap energy distribution in gate stack during PBTI stress is extracted by using ramped recovery stress, and the temperature dependences of PBTI（90℃,125℃, 160℃） are studied and activation energy（Ea） values（0.13 eV and 0.15 eV） are extracted. Although the equivalent oxide thickness（EOT） values of two TiN thickness values are almost similar（0.85 nm and 0.87 nm）, the 2.4-nm TiN one（thicker Ti N capping layer） shows better PBTI reliability（13.41% at 0.9 V, 90℃, 1000 s）. This is due to the better interfacial layer/high-k（IL/HK） interface, and HK bulk states exhibited through extracting activation energy and trap energy distribution in the high-k layer.

关 键 词：positive bias temperature instability（PBTI） HK/MG Ea trap energy distribution 

分 类 号：TN386[电子电信—物理电子学] TQ153.13[化学工程—电化学工业]