光刻机物镜底部污染对策研究

Study on Pollution Control at the Bottom of Lithographic Projection System

为满足光刻机物镜底部污染控制需求,在传统吹扫式气帘的基础上提出了填充式物镜气帘设计方案。该气帘利用正压的保护原理,将物镜底部与硅片面有机污染物进行隔离。借助计算流体力学软件提供的组分输运模型,对气帘进行了数值模拟。数值模拟结果表明,填充式物镜气帘的保护效果大幅提升,物镜底部污染物体积百分比降至0.2%以下。搭建了气帘污染实验平台,实验表明,填充式气帘可以有效保护物镜底部镜片不受有机污染物的污染。

In order to meet the needs of pollution control at the bottom of lithographic projection system.This paper presents a design of filled gas curtain based on the sweeping gas curtain.The gas curtain adopts the principle of positive pressure to segregate the organic pollutant at the bottom of objective lens.With the help of component transport model provided by computational fluid dynamics software,numerical simulation of gas curtain is able to be carried out.The result of the simulation indicates that the filled gas curtain is much better than the sweeping gas curtain.The volume fraction of the organic pollutant is smaller than 0.2%.Besides,a experimental platform is built to verify the effect of the filled gas curtain.