کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1787714 | 1023450 | 2011 | 4 صفحه PDF | دانلود رایگان |
The carbon contamination on extreme ultraviolet (EUV) masks is a critical issue causing throughput degradation and unexpected effects on imaging performance. In this work, a series of carbon contamination experiments were performed on a patterned EUV mask. The impact of carbon contamination on imaging performance was analyzed using actinic EUV coherent scattering microscopy (CSM) combined with an in-situ accelerated contamination system (ICS), which was installed on 11B EUVL beam-line at Pohang Light Source (PLS). In addition, the topography of the carbon contamination on the patterned mask was inspected with a scanning electron microscope (SEM). The mask critical dimension (CD) and reflectivity were compared before and after carbon contamination through accelerated exposure. The reflectivity degradation was measured as 5.5% after 3 h exposure which caused ∼20 nm carbon deposition. A mask CD change of 88 nm line and the space pattern showed a similar trend but different absolute values as measured by CSM and CD-SEM. This difference confirms the importance of actinic inspection technique which emulates the practical imaging condition (6° incident angle) as an EUV exposure tool.
Journal: Current Applied Physics - Volume 11, Issue 4, Supplement, July 2011, Pages S107–S110