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Improved Margin of Absorber Pattern Sidewall Angle Using Phase Shifting Extreme Ultraviolet Mask  

Jang, Yong Ju (Department of Nanoscale Semiconductor Engineering)
Kim, Jung Sik (Department of Nanoscale Semiconductor Engineering)
Hong, Seongchul (Department of Materials Science and Engineering, Hanyang University)
Ahn, Jinho (Department of Materials Science and Engineering, Hanyang University)
Publication Information
Journal of the Semiconductor & Display Technology / v.15, no.2, 2016 , pp. 32-37 More about this Journal
Abstract
Sidewall angle (SWA) of an absorber stack in extreme ultraviolet lithography mask is considered to be $90^{\circ}$ ideally, however, it is difficult to obtain $90^{\circ}$ SWA because absorber profile is changed by complicated etching process. As the imaging performance of the mask can be varied with this SWA of the absorber stack, more complicated optical proximity correction is required to compensate for the variation of imaging performance. In this study, phase shift mask (PSM) is suggested to reduce the variation of imaging performance due to SWA change by modifying mask material and structure. Variations of imaging performance and lithography process margin depending on SWA were evaluated through aerial image and developed resist simulations to confirm the advantages of PSM over the binary intensity mask (BIM). The results show that the variations of normalized image log slope and critical dimension bias depending on SWA are reduced with PSM compared to BIM. Process margin for exposure dose and focus was also improved with PSM.
Keywords
EUV lithography; phase shift mask; sidewall angle; aerial image; process window;
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Times Cited By KSCI : 1  (Citation Analysis)
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1 E. van Setten, C. W. Man, R. Murillo, S. Lok, K. van Ingen Schenau, K. Feenstra, C. Wagner, "Impact of mask absorber on EUV imaging performance", Proc. of SPIE, Vol. 7545, 754503 (2010)
2 M. Sugawara and I. Nishiyama, "Impact of slanted absorber side wall on printability in EUV lithography", Proc. of SPIE, Vol. 5992, 59923V (2005)
3 E. Gallagher, G. McIntyre, T. Wallow, S. Raghunathan, O. Wood, L. Kindt, J. Whang, M. Barrett, "EUV masks under exposure: practical considerations", Proc. of SPIE, Vol. 7969, 79690W (2011)
4 S. Lee, I. Lee, J. G. Doh, J. U. Lee, S. Hong, J. Ahn, "Improved imaging properties of thin attenuated phase shift masks for extreme ultraviolet lithography", J. Vac. Sci Technol. B Vol. 31, 021606, pp.1-5 (2013).   DOI
5 S. Hong, S. Jeong, J. U. Lee, S. M. Lee, and J. Ahn., "Stochastic Patterning Simulation Using Attenuated Phase-Shift Mask for Extreme Ultraviolet Lithography", Appl. Phys. Express Vol. 6, 096501, pp.1-4 (2013).   DOI
6 J. Y. Jang, J. S. Kim, S. Hong, H. Cho, and J. Ahn., "Evaluation of Imaging Performance of Phase Shift Mask Depending on Reflectivity with Sub-resolution Assist Feature in EUV Lithography", Journal of the Semiconductor & Display Technology, Vol. 14 (3), pp.1-5 (2015).
7 ITRS organization, "International technology roadmap for semiconductors 2013 edition : Lithography summary", March, 13, 2015 from http://www.itrs2.net, (2014).
8 E. Hoshino, T. Ogawa, N. Hirano, H. Hoko, M. Takahashi, H. Yamanashi, A. Chiba, M. Ito, S. Okazaki, "Dry Etching of Ta Absorber for EUVL Masks", Proc. of SPIE, Vol. 4186, pp. 749-755 (2001).
9 R. Wistrom, Y. Sakamoto, J. Panton, T. Faure, T. Isogawa, A. McGuire, "Controlling the sidewall angle of advanced attenuated phase-shift photomasks for 14nm and 10nm lithography", Proc. of SPIE, Vol. 8880, 88800W (2013).
10 J. Karttunen, J. Kiihamaki, S. Franssila, "Loading effects in deep silicon etching", Proc. of SPIE, Vol. 4174, pp. 90-97 (2000)
11 S. Jensen and O. Hansen, "Characterization of the Microloading Effect in Deep Reactive Ion Etching of Silicon", Proc. of SPIE, Vol.5342 (2004).
12 C. Hedlund, H.?O. Blom, and S. Berg, "Microloading effect in reactive ion etching", J. Vac. Sci. Technol A, 12 (4), pp. 1962-1965 (1994)   DOI
13 Y. Du, C. J. Choi, G. Zhang, S. Park, P. Yan, and K. Baik, "TaN-based EUV Mask Absorber Etch Study", Proc. of SPIE, Vol. 6283, 62833D (2006)
14 U. Dersch, A. Korn, C. Engelmann, C. Georg Frase, W. Hassler-Grohne, H. Bosse, F. Letzkus, J. Butschke, "Impact of EUV Mask Pattern Profile Shape on CD Measured by CD-SEM", Proc. of SPIE, Vol. 5752 (2005)
15 T. Abe, A. Fujii, S. Sasaki, H. Mohri, N. Hayashi, T. Shoki, T. Yamada, O. Nozawa, R. Ohkubo and M. Ushida, "Process development for EUV mask production", Proc. of SPIE, Vol. 6349, 63493G (2006)