control of the self-assembly process. BCP SA usually occurs below a certain
concentration during evaporation of the solvent in BCP solutions. The concentration depends mostly on the solubility of the various blocks of the BCP in the solvent
as well as temperature. Despite the existence of a final equilibrium morphology in
the condensed state, the resulting structure often varies with experimental
parameters because metastable states are frequently observed as a result of the
Fig. 6 (a) Generation of single-crystal homoepitaxial Si (experiment 1) and heteroepitaxial NiSi
(experiment 2) nanostructures. The left bottom photograph shows Si wafer with bare crystalline Si
substrate (blue arrow), with a-Si deposited (red arrow) and spots after laser-induced crystallization
(green arrows). Boxes in (d) show regions with (top) and without (bottom) Ni signal in the TEM
thus demonstrating the boundaries of the interface. (b, c) TEM images of Si nanostructure crosssections. (d) Scanning TEM image of a NiSi pillar cross-section on Si (reprinted with permission
from [44]; Copyright 2010 AAAS)
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K. Hur and U. Wiesner