کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5364759 | 1388320 | 2010 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Secondary electron yield measurements of carbon covered multilayer optics Secondary electron yield measurements of carbon covered multilayer optics](/preview/png/5364759.png)
Carbon contamination on extreme ultraviolet (EUV) optics has been observed in EUV lithography. In this paper, we performed in situ monitoring of the build-up and removal of carbon contamination on Mo/Si EUV multilayers by measuring the secondary electron yield as a function of primary electron energy. An electron beam with an energy of 2Â keV was used to simulate the EUV radiation induced carbon contamination. For a clean EUV multilayer, the maximum secondary electron yield is about 1.5 electrons per primary electron at a primary electron energy of 467Â eV. The maximum yield reduced to about 1.05 at a primary electron energy of 322Â eV when the surface was covered by a non-uniform carbon layer with a maximum thickness of 7.7Â nm. By analyzing the change in the maximum secondary electron yield with the final carbon layer thickness, the limit of detection was estimated to be less than 0.1Â nm.
Journal: Applied Surface Science - Volume 257, Issue 2, 1 November 2010, Pages 354-361