Vapor-phase growth and characterization of luminescent silicon layers

We discuss the vapor-phase technique for porous silicon formation and the structural, optical and electrical properties of the layers with emphasis on the statistical and fractal analysis of Atomic Force Microscopy (AFM) images. First-order and second order parameters of different AFM images of vapor-phase grown layers were calculated. We found a trend towards slightly lower roughness exponents for vapor-phase samples, possibly related with improved structural reproducibility. The current-voltage characteristics show an exponential dependence with voltage, followed by a power-law relationship, typical of space charge limited currents in high resistivity materials.