不同本底真空制备的Yb/Al多层膜结构和反射率研究

Study on the Structure and Reflectivity of Yb/Al Multilayers Prepared by Different Base Pressure

为研究本底真空对Yb/Al多层膜微结构和光学性能的影响,使用直流磁控溅射设备,在本底真空度分别为4×10^(-5)Pa、8×10^(-5)Pa、1×10^(-4)Pa、2×10^(-4)Pa和4×10^(-4)Pa条件下,制备了一组结构相同的SiC/(Yb/Al)_(3)周期多层膜。使用X射线掠入射反射、原子力显微镜及大角X射线衍射等方法表征了样品表面和内部结构,结果表明:当本底真空度从4×10^(-4)Pa提高至4×10^(-5)Pa时,Yb/Al多层膜的平均界面宽度从2.15 nm减小到1.82 nm;表面粗糙度从1.87 nm减小到1.43 nm;膜层内有Yb、Yb2O3和Al结晶,结晶尺寸随真空度略有增加。SiC/(Yb/Al)_(3)周期多层膜为张应力,当本底真空度从4×10^(-4)Pa提升至4×10^(-5)Pa时,应力从85 MPa增大到142 MPa。测试了本底真空度为4×10^(-5)Pa时制备的多层膜样品的反射率,在波长为73.6 nm、入射角为5°时,反射率为31.3%。

In order to study the effect of base pressure on the microstructure and optical properties of Yb/Al multilayers,a series of SiC/(Yb/Al)_(3) period multilayers with the same structure were prepared by DC magnetron sputtering under base pressure conditions of 4×10^(-5)Pa,8×10^(-5)Pa,1×10^(-4)Pa,2×10^(-4)Pa and 4×10^(-4)Pa,respectively.The surface and internal structures of Yb/Al multilayers were characterized by X-ray grazing incident reflection,atomic force microscopy and wide-angle X-ray diffraction.The results show that the average interface width of Yb/Al multilayers decreases from 2.15 nm to 1.82 nm with the raise of base pressure from 4×10^(-4)Pa to 4×10^(-5)Pa;the surface roughness decreases from 1.87 nm to 1.43 nm.Yb,Yb_(2)O_(3) and Al polycrystalline grains are formed in the film,and the grain size increases slightly.The stress of SiC/(Yb/Al)3 period multilayer is tensile,and the stress increases from 85 MPa to 142 MPa with the base pressure raising from 4×10^(-4)Pa to 4×10^(-5)Pa.The reflectivity of the sample prepared under 4×10^(-5)Pa base pressure was measured.When the wavelength is 73.6 nm and the incident angle is 5°,the reflectivity of the sample is 31.3%.