HfO2的纯度对紫外多层膜反射率的影响

用辉光放电质谱法和二次离子质谱仪测定了两种HfO2材料及它们相应的单层膜中的杂质含量，结果发现，无论是在体材料中还是在用电子束蒸发技术沉积的材料单层薄膜中，ZrO2都是这两种HfO2材料中最主要的杂质。而且，这两种HfO2材料中Zr含量的差别远远大于Ti、Fe含量的差别，这说明Zr含量的差别正是引起两种HfO2膜层光学性能差别的原因。用这两种不同纯度的HfO2材料与同一纯度的SiO2材料组合，沉积形成266nm的紫外反射镜，实验结果表明这两种反射镜的反射率分别在99.85% 和 99.15%左右。这个结果与依据单层膜得出的光学常数所设计的结果符合的很好。

The impurities in two kinds of HfO2 materials and in their corresponding single layer thin films were determined through glow discharge mass spectrum technology and secondary ion mass spectrometry (SIMS) equipment respectively. It was found that ZrO2 was the main impurity in the two kinds of HfO2 either in the original HfO2 materials or in the electron beam deposited films. In addition, the difference of Zr content in the two kinds of HfO2 single layer films was much larger than that of the other impurities such as Ti and Fe, which showed that it was just ZrO2 that made the difference between the optical performance of the film products including the two kinds of HfO2. With these two kinds of HfO2 and the same kind of SiO2, we deposited HfO2/SiO2 multilayer reflective coatings at the wavelength of 266 nm. Experimental results showed that the reflectances of these two mirrors were about 99.85% and 99.15% respectively, which agreed well with the designed results what were based on the optical constants obtained from the corresponding single layer thin films.