摘要
基于Synopsys SWB仿真平台,研究了高K介质金属栅器件中栅功函数变化在N/PMOSFET器件的影响;模拟和分析了金属栅功函数在L gate=32 nm N/PMOSFET器件工作特性提高中的最佳优化方向及其机理。研究结果表明,栅极功函数对N/PMOS器件工作电流I dsat的影响并非简单地单调变化,而是呈现类似钟型分布的特性;存在最佳工作点。同时金属功函数的优化对于器件短沟道效应SCE和关断漏电流的抑制有着显著地影响。此外通过模拟金属栅替代多晶硅栅的应力模拟表明,自去除多晶硅栅到在沉积金属栅的过程中,会对器件沟道区产生明显的应力作用,从而极大提高器件的工作电流特性。因而,采用优化的金属栅代替多晶硅栅结合High-k材料可以有力推动CMOS器件继续沿着摩尔定律向更小器件尺寸的发展。
The metal-gate work function impact on N/PMOSFET device performance is studied and analyzed its optimization using synopsys SWB two-dimensional simulation deck based on 32 nm gate-last HKMG process.Simulation showed that the relationship between gate work function and device drive current Idsat is not a simple monotonous trend but a bell-shape curve and there exists an optimized work function point; the optimized metal-gate work function also has significant help on suppressing the short channel effect （SCE） and device off-current.Secondly,mechanical stress change during gate replacement process was studied based on the gate-last process,where large increment of the compressive stress has been found during the replacement.The large compressive stress resulted in obvious performance improvement shown in the simulation.Optimized metal gate work function combined with gatelast process could have great help on CMOS device further scaling down to below 32 nm is proved.
出处
《科学技术与工程》
北大核心
2013年第30期8921-8927,共7页
Science Technology and Engineering
关键词
金属栅
功函数
短沟道效应
工作电流
后栅工艺
机械应力
metal gate
work function
short channel effect
drive current
gate-last process
mechanical stress
