Ellipsometric studies of porous silicon

The principal angle and ellipticity of the light beam reflected from the su rface of porous silicon (PS) and the dependence on the angle-of-incidence o f the reflected light intensity were measured for three wavelengths of the visible spectral region. The data obtained indicate the presence of a pract ically transparent layer on the PS surface. The layer refraction index and thickness as well as the optical constants of the PS substrate were determi ned. The regions with thicker layers are established as showing more intens e photoluminescence. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.