光刻仿真中二维掩模近场的扩展傅立叶分析和严格耦合波分析-物理学、无线电物理专业论文.docxVIP

光刻仿真中二维掩模近场的扩展傅立叶分析和严格耦合波分析论文摘要(中文) 光刻仿真中二维掩模近场的扩展傅立叶分析和严格耦合波分析 论文摘要(中文) 现代光刻中为了提高系统的分辨率，采用了各种分辨率增强技术：移相掩 模技术、离轴照明、光学临近效应校正等。这些技术必然带来数值孔径的提高、 光刻关键尺寸的减小、掩模厚度的增加等效果。此时，不能再用常规的标量衍 射理论分析掩模的近场，必须采用改进的标量衍射理论或者严格的电磁场方法 来分析入射光经过掩模后的近场。 本文采用扩展傅立叶衍射理论和严格耦合波理论两种方法来分析入射光 透过掩模后的近场分布和衍射效率。本文前面针对交替式相移掩模，提出了一 种考虑阴影效应的近似模型。该方法是傅里叶衍射理论的扩展，是一种依赖于 入射角的函数。并对提出的近似模型的衍射效率以及干涉场光强分布进行了仿 真。之后又应用严格耦合波理论来分析入射光经过掩模后的近场。严格耦合波 方法是通过求解Maxwell方程来求得近场的，推导过程没有用到任何近似，所 以是一种严格的方法。本文中考虑掩模在Y方向是无限大的，所以掩模的模型 是二维的，节省了计算时间。分别计算了TE偏振和TM偏振时二元掩模和衰 减式相移掩模的衍射效率随掩模周期和入射角的变化；偏振度随掩模周期的变 化。这些是标量衍射理论都不能得到的。并将得到的结果与扩展傅立叶衍射理 论进行比较，得到标量的衍射理论跟严格耦合波理论不一致，说明了标量理论 在掩模尺寸与波长相当时就不能用标量衍射理论来模拟入射光经过掩模后的 近场。 关键词：光刻；二元掩模；交替式相移掩模；扩展傅立叶衍射理论；严格耦合 波分析；衍射效率；近场分布 Analysis Analysis of Nearfield for Photomask Based on Extended Fourier Diffraction Theory and Rigorous Coupled—Wave Method 论文摘要(英文) Abstract In order to improve the resolution of photolithographic system，many resolution enhance technology were used which were phase-shifting mask,offaxis illumination，optical proximity correction，and SO on．So the hyper numerical aperture smal l current dimension and thick mask were needed．And then，normal scalar diffraction theory was not exact any more．Extended scalar diffraction theory and rigorous electromagnetic method were used to simulate the nearfields for different mask model．Two methods were used in this paper to get the diffraction efficiencies and the nearfields，one method was called extended fourier diffraction theory,another was called rigorous coupled-wave analysis． However，analysis oftransfer function with Fourier diffraction theory will be inadequate，and shadowing effects must be considered for oblique illumination．Therefore，a new approximation model for alternating phase shift mask considering shadowing effects was proposed in this paper，． Extended Fourier diffraction theory was used，and a relation of function depended on incident angle．Diffraction efficiencies and interference fields were simulated using approximation model． Rig