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Diffusion of Hydrogen Through Hermetic Carbon Films on Silica Fibers

Published online by Cambridge University Press:  21 February 2011

P. J. Lemaire ,
K. L. Walker ,
K. S. Kranz ,
R. G. Huff  and
F. V. DiMarcello
P. J. Lemaire
Affiliation:
AT&T Bell Laboratories, 600 Mountain Avenue, Murray Hill, NJ 07974
K. L. Walker
Affiliation:
AT&T Bell Laboratories, 600 Mountain Avenue, Murray Hill, NJ 07974
K. S. Kranz
Affiliation:
AT&T Bell Laboratories, 600 Mountain Avenue, Murray Hill, NJ 07974
R. G. Huff
Affiliation:
AT&T Bell Laboratories, 600 Mountain Avenue, Murray Hill, NJ 07974
F. V. DiMarcello
Affiliation:
AT&T Bell Laboratories, 600 Mountain Avenue, Murray Hill, NJ 07974
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Abstract

Recent work has made it possible to deposit hermetic carbon coatings on optical fibers during the drawing process. These coatings are used to protect the silica portion of the fiber from undesirable loss increases and strength reductions caused by H2 and H2O, respectively. The hermetic properties of the carbon films have been evaluated using accelerated test conditions where the coated fibers are exposed to H2 at elevated temperatures and hydrogen pressures. In-situ spectral loss monitoring has made it possible to measure changes in the characteristic optical loss features associated with either molecular H2or with species such as OH which form when hydrogen reacts with defects in the silica. By using long lengths of fiber it is thus possible to optically measure the extremely small amounts of hydrogen that penetrate the carbon films during accelerated tests. At temperatures in the range of 100 to 145°C the diffusion of H2 is readily modeled using classical diffusion theories for a composite cylinder, allowing calculation of the diffusion coefficient and the solubility for H2 in the carbon. At higher temperatures the diffusing H2 is partially depleted by reaction with defects in the glass. For these conditions the inward diffusion of the H2 and its reaction at defect sites tend to balance each other, giving rise to a constant, but extremely low, concentration of H2 in the fiber.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 172: Symposium P – Optical Fiber Materials and Processing , 1989 , 85
Copyright
Copyright © Materials Research Society 1990

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References

1. Stone, J., Chraplyvy, A.R., and Burrus, C.A., Opt. Lett. 7, 297 (1982).Google Scholar
2. Noguchi, K., Murakami, Y., and Ishihara, K., Electr. Lett. 19, 1045 (1983).Google Scholar
3. Tomita, A. and Lemaire, P.J., Electr. Lett. 21, 71 (1985).CrossRefGoogle Scholar
4. Huff, R.G., DiMarcello, F.V., and Hart, A.C. Jr., Optical Fiber Communications Conference: Technical Digest, (OFC 88 Conf. Proc., New Orleans, LA 1988) Paper TUG2.Google Scholar
5. Lu, K.E., Lee, M.T., Powers, D.R., and Glaesemann, G.S., Optical Fiber Communications Conference: Postdeadline Papers, (OFC 88 Conf. Proc., New Orleans, LA 1988) Paper PD1-1.Google Scholar
6. Lemaire, P.J., Kranz, K.S., Walker, K.L., Huff, R.G., and DiMarcello, F.V., Electr. Lett. 24, 1323 (1988).Google Scholar
7. Crank, J., The Mathematics of Diffusion, (Oxford University Press, London, 1975), pp.49–53.Google Scholar
8. Shackelford, J.F., Studt, P.L., and Fulrath, R.M., J. Appl. Phys. 43, 1619 (1972).Google Scholar
9. Shelby, J.E., J. Appl. Phys. 48, 3387 (1977).CrossRefGoogle Scholar