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Fabrication of Micro-Relief Structures in Thick Resist for Anti-Counterfeiting Applications

Published online by Cambridge University Press:  11 February 2011

Patrick W. Leech
Affiliation:
CSIRO Manufacturing and Infrastructure Technology, Melbourne, AUSTRALIA.
Henning Zeidler
Affiliation:
Chemnitz Technical University, Chemnitz, GERMANY.
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Abstract

Micro-relief surfaces including grating structures, greytone/micrographic features and microramps have been fabricated with depth features of up to 30 μm. Grey scale lithography has been used to produce the microstructures by a single UV exposure into a layer of thick resist. Arrays of the pixelated microstructures have formed the security features on the surface of optically variable devices. Each of the microstructures was designed to provide an intended optical effect in features such as portraits, symbols and lettering which comprised a larger image (typically 2.5 × 3 cm). An essential part of the process has been the determination of the optimum conditions for coating of the thick resist (AZ P4620) as a function of spin speed and exposure.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

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References

REFERENCES

1. Reimer, K., Hoffman, U., Jurss, M., Pilz, W., Quenzer, H.J. and Wagner, B., Proc. SPIE 3226, Microelectronic Structures and MEMS for Optical Processing III, Austin, 6, (1997).Google Scholar
2. Gimkiewicz, C., Hagedorn, D., Jahns, J., Kley, E-B. and Thoma, F., Applied Optics 38(14), 2986 (1999).Google Scholar
3. Daschner, W., Long, P., Larsson, M. and Lee, S.H., J. Vac. Sci. Technol. B13(6), 2729 (1995).Google Scholar
4. Wu, H., Odom, T., Whitesides, G.M., Anal. Chem. 74, 3267 (2002).Google Scholar
5. Haslop, J.M., “The Evolving Threat”, 9th Interpol Conference on Currency Counterfeiting”, Helsinki, (June, 1997).Google Scholar
6. Leech, P.W., Sexton, B.A. and Marnock, R.J., Microelectronic Engineering 60, 339 (2002).Google Scholar
7. Lee, R.A., Microelectronic Engineering 53, 513 (2000).Google Scholar
8. Lee, R.A., Microelectronic Engineering 61–62, 105 (2002).Google Scholar
9. Gale, M., Physics World 24, (1989).Google Scholar
10. Henke, W., Hoppe, W., Quenzer, H.J., Staudt-Fischbach, P., Wagner, B., Proc. IEEE Micro Electro Mechanical Systems, 205, (1994).Google Scholar