Control of nucleation to realize high density Si nanoparticles on SiO_2 thin films

摘要

A non-thermal method to facilitate nucleation for subsequent thermal chemical vapor deposition of Si nanoparticles on SiO_2/Si(001) with high density and uniform size is demonstrated.Submonolayers of Si adatoms are predeposited on SiO_2/Si(001) substrates by hot-wire chemical vapor deposition with disilane in an UHV chamber.The nanoparticles are grown with a disilane pressure of 1X10~(-4) Torr at 550degC.The Si nanoparticles density is increased and size distribution is narrowed by predeposition of Si adatoms when compared to thermal growth on bare SiO_2/Si(001).The nanoparticles density can be controlled by the amount of Si adatom predeposition.1.2X10~(12) cm~(-2) density and 5.5nm size are demonstrated on SiO_2/Si(001) under UHV-CVD conditions.