叠层高k栅介质中远程界面粗糙散射的理论模型

A Theory Model on Remote-interface-roughness-scattering from High-k/Interlayer Dielectric Stacks

利用双子带近似,从理论上研究了远程界面粗糙散射对叠层高k栅介质MOSFET反型载流子迁移率的退化作用,模拟了叠层高k栅介质结构参数和材料参数对远程界面粗糙散射的影响。结果表明,对于精确的迁移率模型,远程界面粗糙散射必须加以考虑,另外,在设计叠层高k栅介质MOSFET时,在EOT得到满足的条件下,尽可能利用具有较高介电常数的界面层和具有较低介电常数的高k栅介质,可以减小迁移率退化。

The degradation of carrier mobility caused by remote-interface-roughness-scattering was simulated using two-subband model.The effects of permittivity and thicknesses of high-k and interlayer on RIRS-limited mobility were discussed.The simulated results show that an interlayer dielectric with higher permittivity and high-k dielectric with lower permittivity are preferred to keep high mobility and small EOT.