Fabry-Perot interferometer and optical waveguide based on porous silicon nanostructured thin films

In this study, the porous silicon thin films are prepared by electrochemical anodization of highly doped ptypesilicon wafer in ethanoic HF electrolyte. FESEM analyses revealed vertically aligned silicon nanopillarsperpendicular to the Si substrate surface in thin films. The reflection spectra of the samples with differentcircumstances were then studied. Fabry-Perot fringes in the visible-NIR reflection spectrum of appropriatelynanostructured porous silicon thin films were demonstrated. Optical parameters such as refractive indices wereextracted of the results by taking into consideration the relationship between the optical path in the plane-parallel filmand the position of extrema in the reflection spectra. We have also determined the porosities of the PSi layers usingBruggeman’s effective medium approximation from obtained refractive indices. Then we have fabricated two-layerstructures as planar optical waveguides with different refractive indices by controlling the fabrication parameters suchas current density, anodization time, and electrolyte composition, on the basis of the fabricated single-layers.

کلیدواژه ها:

porous silicon ، Fabry-Perot interferometer ، optical waveguide ، nanostructure ، refractive index