Abstract
Porosity depth profiles with exponential or sinusoidal shape were fabricated electrochemically in crystalline silicon using time-variable current densities and studied employing variable angle spectroscopic ellipsometry. Since volume porosity in porous silicon depends on the current density, it was possible to electrochemically tailor porosity depth profiles, which in a first approximation resembled the time modulation of the applied current. Optical characterization of the samples were realized using multilayer optical models and the Bruggeman effective medium approximation allowing variations of the index of refraction according to the applied current density profiles. The analysis also revealed deviations from desired profiles in terms of in-depth inhomogeneities.
Similar content being viewed by others
References
L.T. Canham, Appl. Phys. Lett. 57, 1406 (1990).
A. Halimaoui, C. Oules, G. Bomchil, A. Bsiesy, F. Gaspard, R. Herino, M. Ligeon and F. Muller, Appl. Phys. Lett. 59, 304 (1991).
S. Zangooie, R. Jansson and H. Arwin, J. Vac. Sci. Technol. A 16, 2901 (1998).
S. Zangooie, R. Jansson and H. Arwin, J. Appl. Phys., In press.
U. Grtining and V. Lehmann, Photonic Band Gap Materials, Kluwer Academic Publishers, Netherlands, 1996, p. 453.
S. Zangooie, R. Bjorklund and H. Arwin, Sens. Actuators B 43, 168 (1997).
T. Laurell, J. Drott, L. Rosengren and K. Lindstrdm, Sens. Actuators B 31, 161 (1996).
A. Janshoff, K.S. Dancil, C. Steinem, D.P. Greiner, V.S.-Y. Lin, C. Gurtner, K. Motesharei, M.J. Sailor and M.R. Ghadiri, J. Am. Chem. Soc. 120, 12108 (1998).
R.L. Smith and S.D. Collins, J. Appl. Phys. 71, R1 (1992).
S. Zangooie, R. Jansson and H. Arwin, Appl. Surf. Sci. 136, 123 (1998).
A. Loni, L.T. Canham, M.G. Berger, R. Arens-Fischer, H. Miiunder, H. Ltith, H.F. Arrand and T.M. Benson, Thin Solid Films 276, 143 (1996).
S. Zangooie, R. Bjorklund and H. Arwin, J. Electrochem. Soc. 144, 4027 (1997).
S. Zangooie, R. Bjorklund and H. Arwin, Thin Solid Films 313–314, 827 (1998).
R.M.A. Azzam and N.M. Bashara, Ellipsometry and Polarized Light, North-Holland, New York, 1997.
S. Billat, M. Thönissen, R. Arens-Fischer, M.G. Berger, M. Krüger, and H. Lüth, Thin Solid Films 297, 22 (1997).
M. Thönissen, M.G. Berger, S. Billat, R. Arens-Fischer, M. Krüger, H. Lüth, W. Theiß, S. Hillbrich, P. Grosse, G. Lorendel and U. Frotscher, Thin Solid Films 297, 92 (1997).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Zangooie, S., Jansson, R. & Arwin, H. Electrochemical Tailoring and Optical Investigation of Advanced Refractive Index Profiles in Porous Silicon Layers. MRS Online Proceedings Library 557, 195–200 (1999). https://doi.org/10.1557/PROC-557-195
Published:
Issue Date:
DOI: https://doi.org/10.1557/PROC-557-195