Isolated SiC nanocrystals in SiO2 -: art. no. 253109

A simple method, compatible with conventional silicon technology, is introduced to generate SiC nanocrystals, embedded in SiO2 on Si, and aligned parallel with the interface. The nanometer-sized SiC grains were grown into SiO2 close to the Si/SiO2 interface by a two-step annealing of oxide covered Si: first in a CO, then in a pure O-2 atmosphere. The first (carbonization) step creates epitaxial SiC crystallites grown into the Si surface, while the second (oxidation) step moves the interface beyond them. Conventional and high-resolution cross-sectional electron microscopy shows pyramidal Si protrusions at the Si/SiO2 interface under the grains. The size of the grains, as well as their distance from the Si/SiO2 interface (peak of pyramids) can be controlled by the annealing process parameters. (c) 2005 American Institute of Physics.