Effect of interface-roughness scattering on mobility degradation in SiGe p-MOSFETs with a high-k dielectric/SiO2 gate stack

• 来源期刊: 中国物理B（英文版）
• 关键词: MOSFET high-k dielectric SiGe interface roughness scattering Co.omb scattering
• 年，卷（期）: 2007,（12）
• 页码范围: 3820-3826
• 页数: 7页
• 语种: 英文

摘要

A physical model for mobility degradation by interface-roughness scattering and Coulomb scattering is proposed for SiGe p-MOSFET with a high-k dielectric/SiO2 gate stack. Impacts of the two kinds of scatterings on mobility degradation are investigated. Effects of interlayer (SiO2) thickness and permittivities of the high-k dielectric and interlayer on carrier mobility are also discussed. It is shown that a smooth interface between high-k dielectric and interlayer, as well as moderate permittivities of high-k dielectrics, is highly desired to improve carriers mobility while keeping a low equivalent oxide thickness. Simulated results agree reasoably with experimental data.