论文部分内容阅读
报道了国内首块用于极紫外投影光刻系统的6inch(1inch=2.54cm)标准极紫外光刻掩模。论述了32nm节点6inch标准极紫外光刻掩模的设计方案,及掩模衬底、反射层、吸收层材料的工艺特性研究,对缺陷控制及提高掩模效率的方法进行了分析。运用时域有限差分法对掩模的光学特性进行了仿真,根据仿真结果确定合适的Cr吸收层厚度。运用电子束光刻技术进行了掩模的图形生成,针对其中的电子束光刻临近效应进行了蒙特卡罗理论分析,用高密度等离子体刻蚀进行了图形转移,所制造的掩模图形特征尺寸小于100nm,特征尺寸控制精度优于20nm,满足技术设计要求。
A 6inch (1inch = 2.54cm) standard EUV lithography mask was first reported for the EUV lithography system in China. The design scheme of 6inch standard EUV lithography mask at 32nm node, the process characteristics of mask substrate, reflective layer and absorber layer were discussed. The defect control and the method of improving mask efficiency were also analyzed. The optical properties of the mask were simulated by finite difference time domain method. The thickness of Cr absorber layer was determined according to the simulation results. The pattern generation of the mask was carried out by electron beam lithography. The Monte Carlo method was used to analyze the proximity effect of electron beam lithography. The pattern transfer was performed by high density plasma etching. The mask pattern features Size less than 100nm, feature size control accuracy better than 20nm, to meet the technical design requirements.