Simulated annealing of porous silicon

Porous silicon is a new material with a high potential for the fabrication of electronic devices and solar cells. Changes in the morphology during the rmal treatment are decisice for semiconductor processes such as epitaxy on porous silicon. We introduce a two-dimensional model to simulate the anneal ing behaviour of porous silicon. Our model is based on thermally activated jumps of surface atoms to neighbouring positions. The model qualitatively e xplains experimental findings like the closing of the surface and the fomat ion of a separation layer during annealing. Our simulations and measurement s reveal the formation of voids that are bounded by low-energy facets.