Oxidised porous silicon/disperse red 1 composite material : fabrication and micro-Raman spectrometry analysis

Single porous silicon layers (60%, 70% and 80% porosity) and double porous silicon layers with two different porosities (80%-73% and 73%-80%) were completely oxidised and then filled by Disperse Red One molecules (referred to as DR1). The formed composite materials were characterised by optical reflectivity measurements and micro-Raman spectrometry in order to probe the DR1 relative concentration profile along the porous layers. In the single layers, the Raman signals linearly increase with porosity starting from a critical value (estimated at 40% before oxidation). On the contrary, in the case of double layer systems, the DR1 filling was always higher in the low porosity layer.