光刻照明系统中新型均匀性补偿器的设计

在超大规模集成电路中,为了满足波长193 nm数值孔径为1. 35的45 nm节点紫外光刻曝光光学系统对高分辨率的要求,设计了一种新型的均匀性补偿器件,用于提高照明系统的出射光均匀性从而实现光刻线条的高度均一性。该照明均匀性补偿器的主要功能是实现对照明视场的能量分布进行微调,从而减小系统的残余不均匀性,保证系统在掩膜面及硅片面上的能量分布均匀性达到更高指标的要求。此外,使用CODE V软件对该照明系统的均匀性进行仿真分析,研究发现采用新型均匀性补偿器可以在传统照明和离轴照明模式下同时的光刻照明系统对掩膜面的非均匀性均低于0. 5%。与传统匀光单元相比,该新型均匀性补偿器在不增加光刻照明系统机械设计和控制难度的基础上可明显提高光刻照明系统的均匀性,故该器件具有更好的应用价值和实用意义。

Design and analysis on a novel uniform compensator in lithography lighting system

In order to satisfy the high resolution requirement of lithography exposure optical system,which wavelength is 193 nm,numerical aperture NA is 1.35,as well as its node is 45 nm,a novel lighting system with high uniformity has been proposed.The compensator of lighting system can adjust the energy distribution of illumination field,deduce the residual in-homogeneity of system,and ensure that higher uniformity index on the surfaces of mask and silicon.Through CODE V software,the uniformity of the lighting system was simulated.It is demonstrated that,under the traditional and off ais illumination mode,this system make the uniform of mask lower than 0.5%.Compared with tra ditional uniform Hlumination unit,while the mechanical design and control difficulty of lithography illumination system weren,t increased,the new uniform compensator improved the uniformity of lithography illumination system.So the device has the better applied value and practical significance.