Thursday, August 26, 2010

US Patent 7781778 - LED employing nanowires and phosphor film

This patent from Samsung teaches forming transparent conductive oxide nanowires in a light path of a semiconductor LED to improve light extraction efficiency. Claim 1 reads:

1. A semiconductor light emitting device comprising:

a substrate;

a light emitting structure comprising a first conductivity type semiconductor layer, an active layer and a second conductivity type semiconductor layer sequentially formed on the substrate;

a plurality of nanowire structures formed on the light emitting structure and formed of a transparent material; and

a phosphor film formed on at least an upper surface and a side surface of each of the plurality of nanowire structures, wherein the phosphor film is additionally formed on the entire area of upper surfaces of the light emitting structure exposed between the plurality of nanowire structures.