We present observations of optical second-harmonic generation (SHG) from si
licon nanocrystals embedded in SiO2. SHG sensitivity to Si/SiO2 interface s
tates, charge on the nanocrystals, and particle density gradients is demons
trated. SHG is proven to be a powerful noncontact nondestructive diagnosis
tool for characterization of Si-nanocrystal-based devices and materials. (C
) 2001 American Institute of Physics.