  Single-crystal nanoparticles of silicon, several tens of nm in diameter, may
be suitable as building blocks for single-nanoparticle electronic devices.
Previous studies of nanoparticles produced in low-pressure plasmas have
demonstrated the synthesis nanocrystals of 2-10 nm diameter but larger
particles were amorphous or polycrystalline. This work reports the use of a
constricted, filamentary capacitively coupled low-pressure plasma to produce
single-crystal silicon nanoparticles with diameters between 20-80 nm. Particles
are highly oriented with predominant cubic shape. The particle size
distribution is rather monodisperse. Electron microscopy studies confirm that
the nanoparticles are highly oriented diamond-cubic silicon.
