Extraordinary crystallization of amorphous Si/SiO2 superlattices

Abstract Ordered Si crystals with nanometer sizes are prepared in a Si/SiO 2 superlattice structure using rf sputtering and plasma oxidation. Decreasing the a-Si layer thickness to 1.9 nm increases the inhomogeneous strain by one order of magnitude. An exponential increase of the crystallization temperature with decreasing thickness is found. A new model using the melting temperature and the interior amorphous crystallization temperature is reported. The extension of the model to Ge/SiO 2 and Si/SiO x superlattices is demonstrated.