Generation of a porous device layer on SOI substrates

This article deals with the application of metal assisted chemical etching on SOI substrates. Besides from demonstrating the generation of a porous device layer, the etch behavior after reaching the buried oxide presents new insights on the etch process itself. The catalyst particle position over time is derived from scanning electron micrographs. Also the etch rates for n and p-doped samples are compared and the impact of illumination on the porosification is determined. Finally, the etch behavior after the device layer is fully porosified is discussed, thus focusing on the catalyst movement during metal assisted chemical etching.