Tan C B, Khoh A, Yeo S H
Nanyang Technological University, School of Mechanical and Aerospace Engineering, Singapore 639798.
Opt Express. 2008 Mar 17;16(6):3589-603. doi: 10.1364/oe.16.003589.
In this paper, a model for electromagnetic scattering of line structures is established based on high frequency approximation approach - ray tracing. This electromagnetic ray tracing (ERT) model gives the advantage of identifying each physical field that contributes to the total solution of the scattering phenomenon. Besides the geometrical optics field, different diffracted fields associated with the line structures are also discussed and formulated. A step by step addition of each electromagnetic field is given to elucidate the causes of a disturbance in the amplitude profile. The accuracy of the ERT model is also discussed by comparing with the reference finite difference time domain (FDTD) solution, which shows a promising result for a single polysilicon line structure with width of as narrow as 0.4 wavelength.
本文基于高频近似方法——射线追踪，建立了线结构电磁散射模型。这种电磁射线追踪（ERT）模型的优势在于能够识别对散射现象总解有贡献的每个物理场。除了几何光学场，还对线结构相关的不同衍射场进行了讨论和公式化。逐步叠加每个电磁场以阐明幅度分布中出现扰动的原因。通过与参考时域有限差分（FDTD）解进行比较，还讨论了ERT模型的精度，结果表明，对于宽度窄至0.4波长的单个多晶硅线结构，该模型给出了很有前景的结果。
