(Phys.org)—Scientists at the University of Texas at Austin and
Cornell University have fabricated the first ordered arrays of
silicon nanocrystals reported to date. Brian A. Korgel and
colleagues developed a new chemical method to generate tiny
silicon crystals—or quantum dots—with precisely controlled size
and then relied on nature to organize them into regular
structures. The new self-assembled arrays, presented in the
journal ChemPhysChem, could help researchers exploit the
promising light-emitting properties of one of the most
commercially important semiconductors. Bulk silicon is used in a
wide range of applications, mainly in the electronics industry,
but it is a weak light absorber and an extremely poor light
emitter, so it is not suitable for uses that require light
emission. These properties change when the crystal shrinks to
the nanoscale. Si quantum dots can exhibit very bright visible
luminescence with size-tunable color, which makes them
interesting for the fabrication of light-emitting diodes (L