Laterally graded periodic Mo/B4C multilayer for extreme ultraviolet wavelength of 6.8-11.0 nm
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摘要: 用直流磁控溅射法结合掩模板控制膜厚的方法在Si衬底上制备了工作于6.8~11.0 nm波段的[Mo/B4C]60横向梯度多层膜。利用X射线掠入射反射测试以及同步辐射反射率测试对梯度多层膜的结构及性能进行了测试。X射线掠入射反射测试结果表明,多层膜周期厚度沿着长轴方向从4.39 nm逐渐增加到7.82 nm,周期厚度平均梯度为0.054 nm/mm。对横向梯度多层膜沿长轴方向每隔5 mm进行了一次同步辐射反射率测试,结果显示,横向梯度多层膜在45°入射角下的反射率约为10%,反射峰的半高全宽介于0.13 nm到0.31 nm之间。Abstract: Laterally graded periodic [Mo/B4C]60 multilayer mirrors for an EUV interval of 6.8-11.0 nm were deposited by direct current magnetron sputtering on silicon substrate. The structure properties and performance of laterally graded [Mo/B4C]60 multilayers were investigated by grazing X-ray reflectivity measurements and synchrotron radiation reflectance measurements. The results show that the multilayer period thickness D-spacing varies linearly from 4.39 nm to 7.82 nm in the long direction of the sample, indicating the average D-spacing gradient of 0.054 nm/mm. Reflectance of all measured point on the mirror is about 10% at the incident angle of 45°. Spectral width (FWHM) of the reflectance peaks varies from 0.13 nm to 0.31 nm with the increase of multilayer period thickness.
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Key words:
- EUV /
- laterally graded periodic multilayer /
- Mo/B4C /
- magnetron sputtering /
- synchrotron radiation
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Table 1. Measured results of the GIXRR shown in Fig. 2 and the synchrotron radiation (SR) shown in Fig. 4
measured location x/mm SR reflective peak λ/nm FWHM, Δλ/nm fitted period thickness D by SR/nm calculated period thickness D by GIXRR/nm 5 10.60 0.31 7.98 7.82 10 10.12 0.29 7.57 7.44 15 9.67 0.27 7.19 7.03 20 9.25 0.27 6.83 6.74 25 8.80 0.26 6.47 6.47 30 8.41 0.23 6.10 6.16 35 8.05 0.20 5.86 5.83 40 7.69 0.19 5.59 5.56 45 7.39 0.18 5.34 5.33 50 7.09 0.17 5.11 5.10 55 6.79 0.16 4.88 4.88 -
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