CAJ | 학술논문

针对高精度数字光刻的缩微光学投影系统，提出并设计了一种适用于0.7XGA 型数字微反射镜(DMD)的6片式数字光刻缩微投影物镜。通过优化和拼接三片式物镜结构，得到数值孔径NA=0.1，放大倍率为-0.2558，分辨力达3.5μm，不受DMD栅格效应影响且达到衍射极限的缩微物镜。经过Zemax软件模拟得到其全视场光程差小于λ/5，145 cycles/mm处的调制传递函数(MTF)大于0.58，充分说明该缩微物镜已经达到光刻物镜设计要求。利用Monte Carlo分析方法，模拟加工装配了100组镜头，设定空间频率为145 cycles/mm时，90%的镜头FMTF>0.55，验证了加工装配实际可行。
침대고정도수자광각적축미광학투영계통，제출병설계료일충괄용우0.7XGA 형수자미반사경(DMD)적6편식수자광각축미투영물경。통과우화화병접삼편식물경결구，득도수치공경NA=0.1，방대배솔위-0.2558，분변력체3.5μm，불수DMD책격효응영향차체도연사겁한적축미물경。경과Zemax연건모의득도기전시장광정차소우λ/5，145 cycles/mm처적조제전체함수(MTF)대우0.58，충분설명해축미물경이경체도광각물경설계요구。이용Monte Carlo분석방법，모의가공장배료100조경두，설정공간빈솔위145 cycles/mm시，90%적경두FMTF>0.55，험증료가공장배실제가행。
For the reduced-magnification optical projection system in high precision digital lithography, a kind of digital lithography projection lens, composed of six lenses and suitable for 0.7XGA Digital Micro-mirror Device (DMD), is developed and designed. Through optimizing and splicing the three pieces of lens’ structure, the objective lens, of which numerical aperture NA=0.1, magnification -0.255 8 and resolution 3.5 μm, is obtained. The results of Zemax software show that it reaches the diffraction limit, which is not affected by DMD grid effect. The optical path difference is less thanλ/5 and MTF is more than 0.58 at 145 cycles/mm, which shows that it meets the requirement of the lithography lens’ design. Utilizing Monte Carlo method to analyze the tolerance, 100 groups of lenses’ assembling and fabricating are simulated. The result indicates 90%of the lenses’ FMTF>0.55 when setting the space frequency to 145 cycles/mm, which verifies the practicability of lenses’ assembling and fabricating.