用于极紫外实验的多层膜镀膜技术
EUV多层膜是为像高次谐波应用这样的实验设计和制作的。在本文中，我们将展示适用于8nm -50nm波段的 Ru/B4C 、 Mo/Si、 Zr/Al Si和 SiC/Mg 多层膜的最新成果。这些多层膜都容易根据实验的具体要求定制参数，包括入射角、峰值波长和带宽。
01
引言
02
8-12nm波段适用的多层膜
图1. Pd/B4C(蓝线)、Ru/B4C(红线)和Mo/B4C(绿线)多层膜的反射率；(a) 8 nm、(b) 10 nm和(c) 12 nm。
图2. 设计用于在入射角为45°，峰值波长为8.8 nm时的Ru/B4C多层膜(蓝点)的反射率谱图，红线为假设层间粗糙度为0.4 nm时的的模拟反射率。
03
波长13.5nm适用的多层膜
图3. Mo/Si多层膜反射率实测图
入射角为6°
入射角为45°
图4. MoSi2/Si窄带多层膜和Ru/Si宽带多层膜的反射率（假设层间粗糙度为0.7 nm）
04
17nm-25nm波段适用的多层膜
图5. Zr/Al-Si(蓝线)、C/Al-Si(红线)和Y/Al-Si(绿线)的模拟反射率
图6. (a) (d)高反射率、(b) (e)窄带反射率和(c) (f)宽带反射率Zr/Al-Si(蓝线)和Mo/Si(红虚线)多层膜的计算反射曲线。(a)、(b)和(c)AOI=0℃，(d)、(e)和(f)AOI=45℃。
注：图5和图6中的计算是假设在像表面无氧化、层间光滑等理想情况下的得到的。
窄带Zr/Al-Si多层膜在入射角为45度时的反射率测量结果如图7所示，峰值波长为(a) 18 nm和(b) 21 nm。表面氧化和层间粗糙度大约为4nm和0.5 nm。该窄带镜在18 nm处的反射率峰值为45%，带宽（半峰全宽FWHM）为0.7 nm，在21 nm处的反射率峰值为34%，带宽（半高全宽FWHM）为0.8 nm。
图7. Zr/Al-Si多层膜在入射角为45°时的反射率
18nm优化
21nm优化
05
25nm-50nm波段适用的多层膜
图8. SiC/Mg窄带多层膜反射率的实测结果；入射角为6度。
图9. Mo/Si宽带多层膜的反射率(蓝线)和反射相位(红虚线），6度入射
两块多层膜
指定覆盖层
06
结论
07
应用实例
NTT 定制 EUV/X-ray 光学元件：
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