# 레이저 직접묘화법을 이용한 미세패턴 전도성 향상에 관한 연구

• Lee, Bong-Gu (Division of Mechanical Engineering, Yeungnam University College)
• 이봉구 (영남이공대학교 기계계열)
• Accepted : 2017.05.12
• Published : 2017.05.31
• 35 4

#### Abstract

In this paper, the conductivity of the fine pattern is improved in the insulating substrate by laser-induced forward transfer (LIFT) process. The high laser beam energy generated in conventional laser induced deposition processes induces problems such as low deposition density and oxidation of micro-patterns. These problems were improved by using a polymer coating layer for improved deposition accuracy and conductivity. Chromium and copper were used to deposit micro-patterns on silicon wafers. A multi-pulse laser beam was irradiated on a metal thin film to form a seed layer on an insulating substrate(SiO2) and electroless plating was applied on the seed layer to form a micro-pattern and structure. Irradiating the laser beam with multiple scanning method revealed that the energy of the laser beam improved the deposition density and the surface quality of the deposition layer and that the electric conductivity can be used as the microelectrode pattern. Measuring the resistivity after depositing the microelectrode by using the laser direct drawing method and electroless plating indicated that the resistivity of the microelectrode pattern was $6.4{\Omega}$, the resistance after plating was $2.6{\Omega}$, and the surface texture of the microelectrode pattern was uniformly deposited. Because the surface texture was uniform and densely deposited, the electrical conductivity was improved about three fold.

#### Keywords

Additive process;electrical conductivity;Laser Induced Forward Transfer;Laser Direct Writing;Microdeposition;Micro-pattern

#### Acknowledgement

Supported by : 영남이공대학교

#### References

1. H. Hidai, H. Tokura, "Direct Laser Writing of Aluminum and Copper on Glass Surfaces from Metal Powder." Appl. Surf. Sci. Vol. 174, No. 2, pp. 118-124, 2001. DOI: https://doi.org/10.1016/S0169-4332(01)00065-4 https://doi.org/10.1016/S0169-4332(01)00065-4
2. D. J. Ehrlich, J. Y. Tsao, "Laser Microfabrication: Thin Film Process and Lithography" Academic press, Boston. Vol. 47, No. 2, pp. 207-208, 1989.
3. J. Bohandy, B. F. Kim, F. J. Adrian, "Metal Deposition from a Supported Metal Film using an Excimer Laser" J. Appl. Phys. Vol. 60, No. 4, pp. 1538-1539, 1986. DOI: https://doi.org/10.1063/1.337287 https://doi.org/10.1063/1.337287
4. H. Yamada, T. Sano, "Optimization of Laser induced Forward Transfer Process of Metal Thin Films". Appl. Surf. Sci. Vol. 198, pp. 411-415, 2002. DOI: https://doi.org/10.1016/S0169-4332(02)00351-3 https://doi.org/10.1016/S0169-4332(02)00351-3
5. E. Laffery, J. Macauley, D. J. Mongey, K. F., P. V. Kelly, G. M. Crean, "Photo Assisted Metallization: Line Resolution Studies", Surface and Coating Technology, Vol. 100-101, pp.80-84, 1998. DOI: https://doi.org/10.1016/S0257-8972(97)00592-6 https://doi.org/10.1016/S0257-8972(97)00592-6
6. B. G. Lee, "Deposition of micropattern using the Laser Direct Write Method with a polymer coating layer", Journal of the Korea Academia-Industrial Cooperation Society, Vol. 15, No. 12, pp. 6980-6985, 2014. DOI: https://doi.org/10.5762/KAIS.2014.15.12.6980 https://doi.org/10.5762/KAIS.2014.15.12.6980
7. B. G. Lee, J. H. Moon, "Microfabrication of Micro-Conductive patterns on Insulating Substrate by Electroless Nickel Plating", Kor. J. Met. Mater., Vol. 48, No. 1, pp. 90-100, 2010. DOI: https://doi.org/10.3365/KJMM.2010.48.01.090 https://doi.org/10.3365/KJMM.2010.48.01.090
8. G. A. Krulik, N. Mandich, "Substitution of Hazardous For Non-hazardous Process Chemicals in the Printed Circuit Industry", Metal Finishing, Vol. 90, No. 25, pp. 49-51, 1992.
9. D. P. Banks, C. Grivas, I. Zergioti, R. W. Eason, "Laser-Induced Forward Transfer-printing of focused ion beam pre-machined crystalline magneto-optic yttrium iron garnet micro-discs", Optics express, Vol. 20, No. 14, pp. 15171-15179, 2008.