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Ablation of Polymers with Pairs of Ultraviolet Laser Pulses with Controlled Temporal Separation

Published online by Cambridge University Press:  25 February 2011

Bodil Braren
Affiliation:
IBM, T. J. Watson Research Center, Yorktown Heights, NY 10598
R. Srinivasan
Affiliation:
IBM, T. J. Watson Research Center, Yorktown Heights, NY 10598
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Abstract

The dependance on the pulse width of the ultraviolet laser ablation and etching of poly(methyl methacrylate) was examined using 40-100 ns pulses. These pulses were created by stitching together two identical pulses, each of 40 ns half-width, which were separated by a set time interval from 0 to 380 ns. The etch depth/pulse is sensitive to the pulse width and, therefore, the power density in this polymer.

The response of PMMA to etching by pairs of pulses suggests that short-lived species which may be electronic states (e.g., triplets) and/or radicals play an important role in the ablation. The shape of the pulse was also found to influence the etch depth/pulse.

The etching of polyimide by these extended pulses shows trends that are opposite to those observed in poly(methyl methacrylate). In this instance the shielding of the latter portion of the incoming pulse by the products that are ablated by the front portion is probably a serious effect.

Type
Research Article
Copyright
Copyright © Materials Research Society 1989

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References

REFERENCES

1. Nikolaus, B., Conference on Lasers and Electro-Optics, San Francisco (1986).Google Scholar
2. Srinivasan, R., Sutcliffe, E. and Braren, B., Appl. Phys. Lett. 51, 1285 (1987).Google Scholar
3. Kuper, S. and Stuke, M., Appl. Phys. B, 44, 199 (1987).CrossRefGoogle Scholar
4. Taylor, R.S., Singleton, D. L. and Paraskevopoulos, G., Appl. Phys. Lett. 50, 1779 (1987).CrossRefGoogle Scholar
5. Klopotek, P., Burghardt, B. and MUckenheim, W., J. Phys. E: Sci. Instrum. 20, 1269 (1987).CrossRefGoogle Scholar
6. Srinivasan, R., Braren, B., Seeger, D. E., and Dreyfus, R. W., Macromolecules, 19, 916 (1986).Google Scholar
7. Sutcliffe, E. and Srinivasan, R., J. Appi. Phys., 60, 3315 (1986).CrossRefGoogle Scholar
8. Srinivasan, R., Sutcliffe, E. and Braren, Bodil, Laser Chem. 9, 147 (1988).CrossRefGoogle Scholar
9. Davis, G. M. and Gower, M. C.. J. Appl. Phys., 61, 2090 (1987).Google Scholar
10. Robin, M., Higher Excited States of Polyatomic Molecules Academic Press, New York, 22 (1974).Google Scholar
11. Srinivasan, R., Braren, B., and Dreyfus, R. W., J. Appl. Phys., 61, 372 (1987).CrossRefGoogle Scholar
12. Williams, M. W., and Arakawa, E. T., J. Appl. Phys., 43, 3460 (1972) and earlier references therein.Google Scholar