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Electrical analysis of femtosecond laser pulse absorption in silicon

Published online by Cambridge University Press:  24 June 2006

E. Coyne*
Affiliation:
Analog Devices, Raheen, Limerick, Ireland National Center for Laser Applications (NCLA), National University of Ireland-Galway, Galway, Ireland
G. M. O'Connor
Affiliation:
National Center for Laser Applications (NCLA), National University of Ireland-Galway, Galway, Ireland
T. J. Glynn
Affiliation:
National Center for Laser Applications (NCLA), National University of Ireland-Galway, Galway, Ireland
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Abstract

We report a study of femtosecond laser pulse absorption of wafer grade silicon with an average pulse duration of 150 fs, centred on a wavelength of 775 nm. The electrical response of the laser excited carriers, over a range of fluences up to the ablation threshold for silicon is analysed. The silicon used for the experiments is a uniformly doped P-type wafer with a concentration of 1 × 1012 cm−3 throughout its volume. The purpose of this work is to use the electrical properties of the excited carriers as a method for analysing the interaction between femtosecond pulses and the silicon lattice below the ablation threshold, and to determine the evolution of the excited carriers after the femtosecond pulse is absorbed in silicon. This paper uses simulation software to solve the ambipolar continuity equation for the evolution of the excited carrier group given the initial values and boundary conditions of the experimental system. The paper derives results for the total number of excited carriers created as a function of laser fluence, in addition to the bulk excited carrier dynamics and lifetime after femtosecond laser excitation. Based on the results for the total number of excited carriers as a function of the average laser fluence, a value of 0.09 J cm−2 is measured as the fluence where lattice defects started to reduce the effective quantity of carriers that could be detected and hence indicated incubation lattice damage.

Keywords

Type
Research Article
Copyright
© EDP Sciences, 2006

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References

Nolte, S., Momma, C., Jacobs, H., Tunnermann, A., Chichkov, B.N., Wellegehausen, B., Welling, H., J. Opt. Soc. Am. B 14, 2716 (1997) CrossRef
Bonse, J., Baudach, S., Kruger, J., Kautek, W., Proc. SPIE 4065, 161 (2000) CrossRef
Pronko, P.P., Dutta, S.K., Squier, J., Rudd, J.V., Du, D., Mourou, G., Opt. Commun. 114, 106 (1995) CrossRef
Gambirasio, A., Bernasconi, M., Colombo, L., Phys. Rev. B 61, 8233 (2000) CrossRef
Amit Pratap Singh, Avinashi Kapoor, K.N. Tripathi, G. Ravindra Kumar, Opt. Laser Technol. 34, 37 (2002) CrossRef
Bonse, J., Wrobel, J.M., Kruger, J., Kautek, W., Appl. Phys. A 72, 89 (2001) CrossRef
Guosheng Zhou, P.M. Fauchet, A.E. Siegman, Phys. Rev. B 10, 5366 (1982) CrossRef
Preston, J.S., Van Driel, H.M., Sipe, J.E., Phys. Rev. B 6, 3942 (1989) CrossRef
Van Driel, H.M., Sipe, J.E., Young, F.J., Phys. Rev. Lett. 26, 1955 (1982) CrossRef
Varel, H., Wahmer, M., Rosenfeld, A., Ashkenasi, D., Campbell, E.E.B., Appl. Surf. Sci. 127–129, 128 (1998) CrossRef
Shockley, W., Haynes, J., Phys. Rev. 81, 835 (1951)
S. Middlehoek, M.J. Geerts, IEEE T. Educ. E-21, 34 (1987)
Lawrence, R., Gibson, A.F., Proc. Phys. Soc. London 65, 994 (1952) CrossRef
Bank, R., Rose, D., Fichtner, W., IEEE T. Electron Dev. 30, 1031 (1983) CrossRef
Rosenfeld, M. Lorenz, R. Stoian, D. Ashkensai, Appl. Phys. A 69, S373 (1999) CrossRef