应变Si NMOS积累区电容特性研究

积累区MOS电容线性度高且不受频率限制, 具有反型区MOS电容不可比拟的优势. 本文在研究应变Si NMOS电容C-V特性中台阶效应形成机理的基础上, 通过求解电荷分布, 建立了应变Si/SiGe NMOS积累区电容模型, 并与实验结果进行了对比, 验证了模型的正确性. 最后, 基于该模型, 研究了锗组分、应变层厚度、掺杂浓度等参数对台阶效应的影响, 为应变Si器件的制造提供了重要的指导作用. 本模型已成功用于硅基应变器件模型参数提取软件中, 为器件仿真奠定了理论基础. 关键词： 应变Si NMOS 积累区电容 台阶效应 电荷分布

Research on the capacitance-voltage characteristic of strained-silicon NMOS accumulation capacitor

Accumulation MOS capacitor is more linear than inversion MOS capacitor and is almost independent of the operation frequency. In this paper, we present first the formation mechanism of the "plateau", observed in the C-V characteristic of the strained-Si NMOS capacitor, and then a physical model for strained-Si NMOS capacitor in accumulation region. The results from the model show to be in excellent agreement with the experimental data. The proposed model can provide valuable reference for the strained-Si device design, and is has been implemented in the software for extracting the parameter of strained-Si MOSFET.