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Resist Requirements and Limitations for Nanoscale Electron-Beam Patterning

Published online by Cambridge University Press:  11 February 2011

J. Alexander Liddle
Materials Sciences Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA
Gregg M. Gallatin
IBM T.J. Watson Research Center Yorktown Heights N.Y. 10598, USA
Leonidas E. Ocola
Advanced Photon Source, Argonne National Laboratory Argonne, IL 60439, USA
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Electron beam lithography still represents the most effective way to pattern materials at the nanoscale, especially in the case of structures, which are not indefinitely repeating a simple motif. The success of e-beam lithography depends on the availability of suitable resists. There is a substantial variety of resist materials, from PMMA to calixarenes, to choose from to achieve high resolution in electron-beam lithography. However, these materials suffer from the limitation of poor sensitivity and poor contrast.

In both direct-write and projection e-beam systems the maximum beam current for a given resolution is limited by space-charge effects. In order to make the most efficient use of the available current, the resist must be as sensitive as possible. This leads, naturally, to the use of chemically amplified (CA) systems. Unfortunately, in the quest for ever smaller feature sizes and higher throughputs, even chemically amplified materials are limited: ultimately, sensitivity and resolution are not independent. Current resists already operate in the regime of < 1 electron/nm2. In this situation detailed models are the only way to understand material performance and limits.

Resist requirements, including sensitivity, etch selectivity, environmental stability, outgassing, and line-edge roughness as they pertain to, high-voltage (100 kV) direct write and projection electron-beam exposure systems are described. Experimental results obtained on CA resists in the SCALPEL® exposure system are presented and the fundamental sensitivity limits of CA and conventional materials in terms of shot-noise and resolution limits in terms of electron-beam solid interactions are discussed.

Research Article
Copyright © Materials Research Society 2003

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1. Abboud, F., Baik, Ki-Ho, Chakarian, V., Cole, D., Daniel, J., Dean, R., Gesley, M., Lu, Maiying, Naber, R., Newman, T., Raymond, F., Trost, D., Wiltse, M., DeVore, W., Proc. SPIE 4562, 1 (2002).Google Scholar
2. Liddle, J.A., Harriott, L.R. and Waskiewicz, W.K., Microlithography World, 6, 15 (1997).Google Scholar
3. Golladay, S. D., Pfeiffer, H. C., Rockrohr, J. D., and Stickel, W., J. Vac. Sci. Technol., B18, 3072 (2000).Google Scholar
4. Brainard, R.L., Barclay, G.G., Anderson, E.H., Ocola, L.E., Microelectronic Engineering, 61–62, 707 (2002)Google Scholar
5. Ohnishi, Y., Mizuko, M., Gokan, H. and Fujiwara, S., J. Vac. Sci. Technol., 19, 1141 (1981).Google Scholar
6. Kunz, R. et al., Proc. SPIE 2724, 365 (1996).Google Scholar
7. Ocola, L.E., to appear in J. Vac. Sci. Technol., Proceedings of the 46th EIPBN meeting.Google Scholar
8. Bowden, M.J., Thompson, L.F. and Ballantyne, J.P., J. Vac. Sci. Technol., 12, 1294 (1975).Google Scholar
9. Thompson, L.F., Ballantyne, J.P. and Feit, E.D., Bowden, M.J., Thompson, L.F. and Ballantyne, J.P., J. Vac. Sci. Technol., 12, 1280 (1975).Google Scholar
10. Allen, R.D., Conley, W.E. and Kunz, R.R., in Microlithography, Micromachining and Microfabrication, edited by Rai-Choudhury, P. (SPIE Optical Engineering Press, Bellingahm, 1997), p. 321.Google Scholar
11. Mkrtchyan, M. M., Liddle, J. A., Berger, S. D., Harriott, L. R., Gibson, J. M. and Schwartz, A. M., J. of Appl. Phys., 78, 6888 (1995).Google Scholar
12. Mkrtchyan, M. M., Liddle, J. A., Stanton, S. T., Munro, E., Waskiewicz, W. K., Microelectronic Engineering, 53, 299 (2000).Google Scholar
13. Fares, N., Stanton, S., Liddle, J. and Gallatin, G., J. Vac. Sci. Technol., B18, 3115 (2000).Google Scholar
14. Stanton, S.T., Proc. SPIE, 4343, 138 (2001).Google Scholar
15. Okamato, K., Suzuki, K., Pfeiffer, H. and Sogard, M., Solid State Technol., May, 118 (2000)Google Scholar
16. Koek, B.H., Chisholm, T., van Run, A.J., Romijn, J., Davey, J.P., Microelectronic Engineering, 23, 81 (1994).Google Scholar
17. Mkrtchyan, M., Gallatin, G., Liddle, A., Zhu, X., Munro, E., Waskiewicz, W., Muller, D., Microelectronic Engineering, 57–58, 277 (2001).Google Scholar
18. Smith, H.I., J. Vac. Sci. Technol., B4, 148 (1986).Google Scholar
19. Gallatin, G.M. and Liddle, J.A., Microelecronic Engineering., 46 365 (1999)Google Scholar
20. Tagawa, S., Nagahara, S., Yamamoto, Y., Werst, D. and Trifunac, A.D., Proc. SPIE 3999, 204 (2000).Google Scholar
21. Saeki, A., Kozawa, T., Yoshida, Y. and Tagawa, S., Jpn. J. Appl. Phys. 41, 4213 (2002)Google Scholar
22. Gallatin, G.M., Proc. SPIE, 4404, 123 (2001).Google Scholar
23. Houle, F.A., Hinsberg, W.D., Sanchez, M.I. and Hoffnagle, J.A., J. Vac. Sci. Technol., B20, 924 (2002).Google Scholar
24. Hinsberg, W.D., Houle, F.A., Sanchez, M.I. and Wallraff, G.M., IBM J. Res. & Dev. 45, 667 (2001).Google Scholar
25. Ocola, L.E., Mat. Res. Soc. Symp. Proc., 705, Y.1.1.1 (2002)Google Scholar
26. Houle, F. A., Hinsberg, W. D., Morrison, M., Sanchez, M. I., Wallraff, G., Larson, C., and Hoffnagle, J., J. Vac. Sci. Technol., B18, 1874 (2000).Google Scholar
27. Anderson, E.H., Olynick, D.L., Chao, W., Harteneck, B. and Veklerov, E., J. Vac. Sci. Technol., B18, 2970 (2000).Google Scholar
28. Joy, D.C., Microelectronic Engineering, 1, 103 (1983).Google Scholar
29. Ocola, L.E., Microelectronic Engineering, 53, 433 (2000).Google Scholar
31. Allee, D.R., Umbach, C.P. and Broers, A.N., J. Vac. Sci. Technol., B9, 2838 (1991).Google Scholar
32. Macaulay, J.M. “The production of nanometre structures in inorganic materials by electron beams of high current density”, Ph.D. dissertation, University of Cambridge (1989).Google Scholar
33. Macaulay, J.M., Allen, R.M., Brown, L.M., Berger, S.D., Microelectronic Engineering, 9, 57 (1989)Google Scholar
34. Broers, A.N., Proc. R. Soc. Lond. A, 416, 1 (1988).Google Scholar
35. Broers, A.N., Phil. Trans. R. Soc. Lond. A, 353, 291 (1995).Google Scholar
36. Williamson, M., Neureuther, A., Proc. SPIE, 3999, 1189 (2000).Google Scholar
37. Sato, M., Ocola, L.E., Novembre, A.E., Ohmori, K., Ishikawa, K., Katsumata, K. and Nakayama, T., J. Vac. Sci. Technol., B17, 2873 (1999).Google Scholar
38. Gonsalves, K.E., Merhari, L., Wu, H., and Hu, Y., Advanced Materials, 13, 703 (2001).Google Scholar