Laser micromachining of permalloy for fine metal mask

  • Junyeon Heo
  • Hyungsuk Min
  • Myeongkyu LeeEmail author


We show that crack-free drilled structures with 25 μm hole size can be fabricated in the 12 μm-thick Permalloy foil by a nanosecond ultraviolet laser with low pulse energy and high repetition rate. The number of pulses required for drilling decreased with increasing pulse energy. The obtained hole exhibited a smaller size than the laser spot, implying that only the central part of a focused Gaussian beam contributed to the drilling. Debris and burr incurring as a result of the laser micromachining could be quickly removed by etching in an HCl/HNO3 solution. This made it possible to obtain a clear structure without any debris remaining on the foil. This laserdirect process may be effectively utilized for fabricating fine metal masks necessary for the production of organic light emitting diode displays and other electronic devices.


Laser micromachining Fine metal mask Permalloy Organic light emitting diode 



directional orientation of the system


strip thickness with strip thickness and strip thickness strip thickness


  1. 1.
    Lih, J. J., Chao, C. I., and Lee, C. C., “Novel Pixel Design for High-Resolution AMOLED Displays with a Shadow Mask,” Journal of the Society for Information Display, Vol. 15, No. 1, pp. 3–7, 2007.CrossRefGoogle Scholar
  2. 2.
    Kim, S., Lee, S., Kim, M., Song, J., Hwang, E., et al., “A 3.0-in. 308-ppi WVGA AMOLED with a Top-Emission White OLED and Color Filter,” Journal of the Society for Information Display, Vol. 17, No. 2, pp. 145–149, 2009.CrossRefGoogle Scholar
  3. 3.
    Vaart, N., Lifka, H., Budzelaar, F., Rubingh, J., Hoppenbrouwers, J., et al., “Towards Large-Area Full-Color Active-Matrix Printed Polymer OLED Television,” Journal of the Society for Information Display, Vol. 13, No. 1, pp. 9–16, 2005.CrossRefGoogle Scholar
  4. 4.
    Shin, H., Kim, H., Lee, H., Yoo, H., Kim, J., et al., “Photoresist-Free Lithographic Patterning of Solution-Processed Nanostructured Metal Thin Films,” Advanced Materials, Vol. 20, No. 18, pp. 3457–3461, 2008.CrossRefGoogle Scholar
  5. 5.
    Kim, J., Kim, J., and Lee, M., “Laser Welding of Nanoparticulate TiO2 and Transparent Conducting Oxide Electrodes for Highly Efficient Dye-Sensitized Solar Cell,” Nanotechnology, Vol. 21, No. 34, pp. 345203, 2010.CrossRefGoogle Scholar
  6. 6.
    Joo, M., Lee, B., Jeong, S., and Lee, M., “Laser Sintering of Cu Paste Film Printed on Polyimide Substrate,” Applied Surface Science, Vol. 258, No. 1, pp. 521–524, 2011.CrossRefGoogle Scholar
  7. 7.
    Joo, M., Lee, B., Jeong, S., and Lee, M., “Comparative Studies on Thermal and Laser Sintering for Highly Conductive Cu Films Printable on Plastic Substrate,” Thin Solid Films, Vol. 520, No. 7, pp. 2878–2883, 2012.CrossRefGoogle Scholar
  8. 8.
    Kim, H., Shin, H., Ha, J., Lee, M., and Lim, K.-S., “Optical Patterning of Silver Nanoparticle Langmuir-Blodgett Films,” Journal of Applied Physics, Vol. 102, No. 8, pp. 083505–083508, 2007.CrossRefGoogle Scholar
  9. 9.
    Shin, H., Lee, H., Sung, J., and Lee, M., “Parallel Laser Printing of Nanoparticulate Silver Thin Film Patterns for Electronics,” Applied Physics Letters, Vol. 92, No. 23, pp. 231107–231109, 2008.CrossRefGoogle Scholar
  10. 10.
    Kim, S., Lee, H., and Lee, M., “Multi-Layered Ag Film Pattern Printed by Spatially Modulated Pulsed Laser Beam,” Applied Surface Science, Vol. 257, No. 18, pp. 8013–8016, 2011.CrossRefGoogle Scholar
  11. 11.
    Ghosh, A. and Mallik, A., “Unconventional Machining Processes,” in: Manufacturing Science East-West Press, pp. 396–403, 2010.Google Scholar
  12. 12.
    Roos, S. O., “Laser Drilling with Different Pulse Shapes,” Journal of Applied Physics, Vol. 51, No. 9, pp. 5061–5063, 1980.CrossRefGoogle Scholar
  13. 13.
    Yang, B. and Lee, M., “Fabrication of Honeycomb Texture on Poly-Si by Laser Interference and Chemical Etching,” Applied Surface Science, Vol. 284, pp. 565–568, 2013.CrossRefGoogle Scholar
  14. 14.
    Yang, B. and Lee, M., “Mask-Free Fabrication of Inverted-Pyramid Texture on Single-Crystalline Si Wafer,” Optics & Laser Technology, Vol. 63, pp. 120–124, 2014.CrossRefGoogle Scholar
  15. 15.
    Morikawa, H., Niinobe, D., Nishimura, K., Matsuno, S., and Arimoto, S., “Processes for Over 18.5% High-Efficiency Multi-Crystalline Silicon Solar Cell,” Current Applied Physics, Vol. 10, No. 2, pp. 210–214, 2010.CrossRefGoogle Scholar
  16. 16.
    Niinobe, D., Morikawa, H., Hiza, S., Sato, T., Matsuno, S., et al., “Large-Size Multi-Crystalline Silicon Solar Cells with Honeycomb Textured Surface and Point-Contacted Rear toward Industrial Production,” Solar Energy Materials and Solar Cells, Vol. 95, No. 1, pp. 49–52, 2011.CrossRefGoogle Scholar
  17. 17.
    Rublack, T., Schade, M., Muchow, M., Leipner, H. S., and Seifert, G., “Proof of Damage-Free Selective Removal of Thin Dielectric Coatings on Silicon Wafers by Irradiation with Femtosecond Laser Pulses,” Journal of Applied Physics, Vol. 112, No. 2, pp. 023521, 2012.CrossRefGoogle Scholar
  18. 18.
    Döring, S., Ullsperger, T., Heisler, F., Richter, S., Tünnermann, A., et al., “Hole Formation Process in Ultrashort Pulse Laser Percussion Drilling,” Physics Procedia, Vol. 41, pp. 431–440, 2013.CrossRefGoogle Scholar
  19. 19.
    Liu, Y., Wang, C., Li, W., Zhang, L., Yang, X., et al., “Effect of Energy Density and Feeding Speed on Micro-Hole Drilling in C/SiC Composites by Picosecond Laser,” Journal of Materials Processing Technology, Vol. 214, No. 12, pp. 3131–3140, 2014.CrossRefGoogle Scholar
  20. 20.
    Romoli, L., Rashed, C., Lovicu, G., Dini, G., Tantussi, F., et al., “Ultrashort Pulsed Laser Drilling and Surface Structuring of Microholes in Stainless Steels,” CIRP Annals — Manufacturing Technology, Vol. 63, No. 1, pp. 229–232, 2014.CrossRefGoogle Scholar
  21. 21.
    Boudinar, N., Djekoun, A., Chebli, A., Otmani, A., Bouzabata, B., et al., “X-ray Diffraction and Mossbauer Spectrometry Investigations of Invar Nanoparticles Produced by Mechanical Alloying,” International Journal Nanoelectronics and Materials, Vol. 3, pp. 143–153, 2010.Google Scholar
  22. 22.
    Chan, C. and Mazumder, J., “One-Dimensional Steady State Model for Damage by Vaporization and Liquid Expulsion due to Laser- Material Interaction,” Journal of Applied Physics, Vol. 62, No. 11, pp. 4579–4586, 1987.CrossRefGoogle Scholar
  23. 23.
    Kar, A. and Mazumder, J., “Two-Dimensional Model for Material Damage due to Melting and Vaporization during Laser Irradiation,” Journal of Applied Physics, Vol. 68, No. 8, pp. 3884–3891, 1990.CrossRefzbMATHGoogle Scholar
  24. 24.
    Ganesh, R., Faghri, A., and Hahn, Y., “A Generalized Thermal Modeling for Laser Drilling Process- I. Mathematical Modeling and Numerical Methodology,” International Journal of Heat and Mass Transfer, Vol. 40, No. 14, pp. 3351–3360, 1997.CrossRefGoogle Scholar

Copyright information

© Korean Society for Precision Engineering 2015

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringYonsei UniversitySeoulSouth Korea

Personalised recommendations