Photoluminescence anisotropy from laterally anodized porous silicon

We report on a technique to fabricate planar structures of porous silicon using standard photolithography and processing steps. Uniform stripes of porous silicon with smooth interfaces with the surrounding silicon have been observed. Using now the freedom to define the crystallographic direction of the anodization process we studied the correlation between the crystallographic orientation of the porous silicon medium and the polarization selection rules of the emitted light. Our main conclusion is that the polarization selection rules are independent of the crystallographic direction of the porous silicon medium and determined solely by the anodization direction.