粗糙度对极紫外投影光刻掩模的影响  

Influence of roughness on extreme ultra-violet lithography mask

作　　者：杨雄[1] 金春水[1] 姚志华[1] 曹健林[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所

出　　处：《光电工程》2005年第10期80-83,共4页Opto-Electronic Engineering

基　　金：应用光学国家重点实验室基金

摘　　要：基于Nevot-Croce模型,计算了一系列具有粗糙界面的极紫外投影光刻掩模的反射光谱。通过拟合计算结果,得到了峰值反射率、带宽和中心波长与粗糙度的函数关系。根据光刻系统对照明均匀性的要求,讨论了在相同粗糙度变化范围内,分别由峰值反射率、带宽和中心波长引起的照明误差。结果表明,粗糙度对极紫外投影光刻掩模的峰值反射率影响最大。当掩模粗糙度为0.85±0.04nm时,峰值反射率将产生±0.9%的波动,并由此产生±1.5%的照明误差。为保证由峰值反射率导致的照明误差小于±1%,极紫外投影光刻掩模的粗糙度必须控制在±0.025nm以内。A series of reflective spectra of EUVL mask with roughness interface are calculated based on Nevot-Croce model. Three functions of peak reflectivity and bandwidth and centroid wavelength related to roughness are obtained by fitting above results. According to the requirements of a lithography exposure system on illumination uniformity, the illumination errors caused by peak reflectivity or bandwidth or centroid wavelength within same range of roughness are discussed. The calculation results show that the influence of roughness on EUVL mask peak reflectivity is the worst. Peak reflectivity with ±0.9% variation will be generated for roughness variation of ±0.04nm at 0.85nm, which will cause an illumination uniformity error of ±1.5%. The roughness of EUVL must be in the range of ±0.025nm so as to ensure the illumination uniformity error resulted from peak reflectivity less than ±1%.

关 键 词：极紫外投影光刻 掩模 粗糙度 反射光谱 多层膜 

分 类 号：TN305.7[电子电信—物理电子学]