Effect of Sample Thickness on SiO2/Si Interface Roughness Characterization through Transmission Electron Microscope Measurements in Strained-Si MOSFETs
Effect of Sample Thickness on SiO2/Si Interface Roughness Characterization through Transmission Electron Microscope Measurements in Strained-Si MOSFETs
复制标题
通过应变硅 MOSFET 中的透射电子显微镜测量样品厚度对 SiO2/Si 界面粗糙度表征的影响
DOI：
10.1149/2.055201jes
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发表时间：
2011
影响因子：
3.9
通讯作者：
S. Takagi
中科院分区：
文献类型：
--
作者：
Yi Zhao;H. Matsumoto;S. Koyama;M. Takenaka;S. Takagi
在这项研究中，我们实验提取的Si/SiO2界面粗糙度的双轴拉伸应变Si（s-Si）MOSFET通过高分辨率透射电子显微镜（TEM）测量与不同的TEM样品厚度。利用SiO2/Si界面粗糙度的数字化数据，应用自回归（AR）模型提取界面粗糙度的功率谱密度S（q），计算了电子和空穴的粗糙散射限制迁移率μ sr。结果表明，由于TEM成像中的投影效应，由界面数据直接确定的SiO2/Si界面粗糙度Δ随TEM样品厚度的增加而减小。结果表明，随着TEM样品厚度的增加，S（q）被低估，μ sr被高估。线性S（q）修正的有效性被证明是有效的，在表示μ sr值，这是通过模拟的投影效应上观察到的界面粗糙度在一个有限厚度的TEM样品验证。
In this study, we experimentally extract Si/SiO 2 interface roughness of biaxially-tensile strained Si (s-Si) MOSFETs through high-resolution transmission electron microscopy (TEM) measurements with the different TEM sample thicknesses. The roughness-scattering-limited mobilities (μ sr) of electrons and holes are calculated by using the digitalized SiO 2/Si interface roughness data and applying the autoregressive (AR) model to the extraction of the power spectral density, S (q), of the interface roughness from the digitalization data. It is found that the roughness height, Δ, of the SiO 2/Si interface, directly determined from the digitalized interface data, decreases with an increase in the TEM sample thickness due to the projection effect in the TEM image formation. As a result, the S (q) is underestimated and μ sr is overestimated with an increase in the TEM sample thickness. The effectiveness of the linear S (q) correction is shown to be effective in representing the μ sr values, which is verified by the simulation of the projection effect on the interface roughness observed in a TEM sample with an finite thickness.