SYNCHROTRON-RADIATION STUDY OF STRUCTURAL-PROPERTIES OF POROUS SILICON

The photoluminescene of porous silicon (PS) layers boron doped is enha nced by anodic oxidation, which gives rise to an electroluminescence p henomenon in the visible range. The anodic oxidation effects on the st ructural properties of PS are reported, studying the Bragg peaks and t he diffuse scattering by means of X-ray diffraction using synchrotron radiation. The decrease of coherent and diffuse scattering intensity c lose to the Bragg peaks for an oxidized sample is associated to an inc rease of the scattering intensity in the whole reciprocal space. At sm all angle values, an isotropic bump is observed which corresponds to t he presence of a thin SiO2 layer at the crystallites surface.