US Patent 7621997 - Multishell nanocrystal fabrication

http://www.freepatentsonline.com/7621997.html

This patent from Samsung teaches the manufacture of heterostructure nanocrystals capable of higher wavelength luminescence at enhanced efficiency. Claim 1 reads:

1. A method for forming a multi-shell nanocrystal structure, comprising:

(a) forming a core nanocrystal; and

(b) simultaneously reacting at least two precursors having different reaction rates to sequentially form at least two shell layers of nanocrystals having different compositions on a surface of the core nanocrystal.