Silicon nanostructure, structural transition

This capability of self-assembly to make ordered arrays of nanostructures is, in essence, nothing new. Crystallization of molecular or atomic species (whether it is the phase transition of liquid water into solid ice, or of liquid silicon into semiconductor-grade silicon crystal) is an example of self-assembly, as are the formation of surfactants in soap bubbles126, the crystallization of viruses for x-ray structure determination127, and the ordering of liquid crystals in displays128. The novelty of self-assembly is in the focus on the formation of matter structured rationally at scales less than 100 nm, and the realization that the only practical method of achieving these structure is to have the components assemble themselves spontaneously. 

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