采用双扫描平台技术的ArF浸液式光刻

ArF Immersion Lithography Using TWINSCAN Technology

在193nm光刻中,已证明水是一种适于浸液式光刻的液体。浸液式光刻提出了一种可将传统的光学光刻拓展到45nm节点,甚至到32nm节点的潜能。另外,利用现有的透镜,浸液式光刻的选择提出了根据实际的数值孔径和特征图形可增大50%及更大的焦深范围。讨论了采用浸液式光刻获得的成像结果和套刻结果。采用一个0.75数值孔径的ArF透镜,我们用双扫描平台技术(TWINSCANTM)组装一台浸液式扫描光刻机的原理型样机。最初的浸液式曝光实验数据证明了焦深的增加较大,同时以高扫描速度保持了图像的对比度。在初期引入的生产型浸液式光刻中,将采用一个0.85数值孔径的ArF透镜。该系统的分辨率将以大于0.5μm的焦深有效地支持65nm节点半导体器件的加工。这种系统初始的成像技术数据证实有效的增大了其焦深范围。

For 193-nm lithography, water proves to be a suitable immersion fluid. ArF immersion offers the potential to extend conventional optical lithography to the 45-nm node and potentially to the 32-nm node. Additionally, with existing lenses, the immersion option offers the potential to increase the focus window with 50% and more, depending on actual NA and feature type. In this paper we discuss the results on imaging and overlay obtained with immersion. Using a 0.75 NA ArF projection lens, we have built a proto-type immersion scanner using TWINSCANTM technology. First experimental data on imaging demonstrated a large gain of depth of focus (DOF), while maintaining image contrast at high scan speed. For first pilot production with immersion, a 0.85 NA ArF lens will be used. The resolution capabilities of this system will support 65 nm node semiconductor devices with a DOF significantly larger than 0.5 μm. Early imaging data of such a system confirms a significant increase in focus window.