Abstract
Crystalline properties of Si films grown on porous Si layers were investigated. Based on the results obtained by Rutherford backscattering spectroscopy and cross-sectional transmission electron microscopy, a model of Si epitaxial growth on a porous Si layer is proposed. In our model dominant defects in the region near the epitaxial layer/porous Si interface and in the one near the surface in the epitaxial layer are dislocations and stacking faults, respectively. The oxidation rate of the porous Si layers is about 80–130× faster than that of the bulk Si, and the etching rate of the oxidized porous Si layers is almost equal to that of the bulk oxide. The effective dielectric constants of the oxidized porous Si layers have a close relation to the anodic current density, ranging from 3.8 to 4.0.