Research of the effects on collection efficiency of mirror thickness in EUV collector

This paper analyzes the mechanism of the mirror thickness's effects on the collection efficiency of the collector in EUV Lithography. A calculation method of collection efficiency is presented with the mirror thickness taken into account. Meanwhile, the curve of collection efficiency with the mirror thickness as the argument is calculated based on our previous designed collector. The collected range of each mirror is calculated under a series of mirror thicknesses. The reason why some inner mirrors lose collected function is also analyzed when the mirror is too thick. The research is meaningful to the design and processing of the collector.